U.S. patent application number 13/913326 was filed with the patent office on 2013-12-26 for starter system for an engine.
The applicant listed for this patent is Briggs & Stratton Corporation. Invention is credited to Jason D. Elvers, Scott A. Funke, Jason A. Hansen, Robert Koenen, Stephen J. Lavender, Ramidu Mirissage, James Nommensen, David W. Procknow.
Application Number | 20130343906 13/913326 |
Document ID | / |
Family ID | 48222757 |
Filed Date | 2013-12-26 |
United States Patent
Application |
20130343906 |
Kind Code |
A1 |
Funke; Scott A. ; et
al. |
December 26, 2013 |
STARTER SYSTEM FOR AN ENGINE
Abstract
A pressure washer includes an engine, a water pump driven by the
engine, a starter motor coupled to the engine to start the engine,
an energy storage device electrically coupled to the starter motor,
a spray device including an activation device for starting and
stopping a flow of water from the spray device, a pressure sensor,
and a flow sensor. The water pump has a low pressure side and a
high pressure side. The high pressure side provides pressurized
water. The pressure sensor is located at the low pressure side and
is configured to indicate a water pressure relative to a threshold
pressure. The flow sensor is located at the low pressure side and
is configured to indicate a water flow relative to a threshold
flow. With the engine off, the starter motor starts the engine when
the pressure sensor indicates the water pressure is above the
threshold pressure and the flow sensor indicates the water flow is
above the threshold flow.
Inventors: |
Funke; Scott A.; (New
Berlin, WI) ; Koenen; Robert; (Pewaukee, WI) ;
Procknow; David W.; (Elm Grove, WI) ; Hansen; Jason
A.; (Elkhorn, WI) ; Lavender; Stephen J.;
(Caledonia, WI) ; Elvers; Jason D.; (Horicon,
WI) ; Mirissage; Ramidu; (Brookfield, WI) ;
Nommensen; James; (Oak Creek, WI) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Briggs & Stratton Corporation |
Wauwatosa |
WI |
US |
|
|
Family ID: |
48222757 |
Appl. No.: |
13/913326 |
Filed: |
June 7, 2013 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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PCT/US2013/035623 |
Apr 8, 2013 |
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13913326 |
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13692739 |
Dec 3, 2012 |
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PCT/US2013/035623 |
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13289613 |
Nov 4, 2011 |
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13692739 |
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61657607 |
Jun 8, 2012 |
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61625437 |
Apr 17, 2012 |
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Current U.S.
Class: |
417/10 |
Current CPC
Class: |
A01D 34/006 20130101;
F04B 49/02 20130101; A01D 34/828 20130101; A01D 34/824 20130101;
F02N 11/101 20130101; F02N 11/0862 20130101; A01D 34/76 20130101;
F02N 11/00 20130101; F04B 17/06 20130101; A01D 34/78 20130101; F02N
11/0803 20130101; A01D 34/6818 20130101; F02N 11/0848 20130101;
F04B 17/05 20130101; F02N 11/0822 20130101; F02N 11/087
20130101 |
Class at
Publication: |
417/10 |
International
Class: |
F02N 11/00 20060101
F02N011/00 |
Claims
1. A pressure washer comprising: an engine; a water pump driven by
the engine, the water pump having a low pressure side and a high
pressure side, the high pressure side providing pressurized water;
a starter motor coupled to the engine to start the engine; an
energy storage device electrically coupled to the starter motor; a
spray device including an activation device for starting and
stopping a flow of water from the spray device; a pressure sensor
located at the low pressure side, the pressure sensor configured to
indicate a water pressure relative to a threshold pressure; a flow
sensor located at the low pressure side, the flow sensor configured
to indicate a water flow relative to a threshold flow; and wherein,
with the engine off, the starter motor starts the engine when the
pressure sensor indicates the water pressure is above the threshold
pressure and the flow sensor indicates the water flow is above the
threshold flow.
2. The pressure washer of claim 1, wherein, with the engine on, the
engine is stopped when the flow sensor indicates the water flow is
below the threshold flow.
3. The pressure washer of claim 1, wherein, with the engine on,
when the flow sensor indicates the water flow is below the
threshold flow for a predetermined amount of time, the engine is
stopped when the predetermined amount of time is met.
4. The pressure washer of claim 3, wherein the engine speed is
reduced during the predetermined amount of time.
5. A pressure washer comprising: an engine; a water pump driven by
the engine, the water pump providing pressurized water; a starter
motor coupled to the engine to start the engine; an energy storage
device electrically coupled to the starter motor; a spray device
including an activation device for starting and stopping a flow of
water from the spray device; a pressure sensor configured to
indicate a water pressure relative to a threshold pressure; a flow
sensor configured to indicate a water flow relative to a threshold
flow; and a controller configured to control the operation of the
engine, wherein, with the engine off, the controller activates the
starter motor to start the engine when the pressure sensor
indicates the water pressure is above the threshold pressure and
the flow sensor indicates the water flow is above the threshold
flow.
6. The pressure washer of claim 5, wherein with the engine on, the
controller is configured to stop the engine when a stopped flow
condition is detected.
7. The pressure washer of claim 5, wherein the controller is
configured to implement an off delay timer set for a predetermined
amount of time, the off delay timer runs when the flow sensor
indicates the water flow is below the threshold flow; and wherein
the controller is configured to stop the engine when the
predetermined amount of time is met.
8. The pressure washer of claim 7, wherein the off delay timer is
reset when the flow sensor indicates the water flow is above the
threshold flow before the predetermined amount of time is met.
9. The pressure washer of claim 5, wherein the controller is
incorporated into the engine.
10. The pressure washer of claim 5, wherein the controller is
incorporated into the energy storage device.
11. The pressure washer of claim 5, wherein the energy storage
device is removably coupled to a receiving port and the controller
is incorporated into a housing of the receiving port.
12. The pressure washer of claim 11, wherein the energy storage
device is rechargeable.
13. The pressure washer of claim 5, wherein the controller is
incorporated into an electric start control module separate from
the engine and the energy storage device.
14. The pressure washer of claim 5, wherein the controller
comprises non-programmable circuitry having discrete
components.
15. The pressure washer of claim 14, wherein the discrete
components include: a starter motor activation circuit configured
to activate the starter motor to start the engine when the pressure
sensor indicates the water pressure is above the threshold pressure
and the flow sensor indicates the water flow is above the threshold
flow; and an off time delay circuit configured to implement a timer
that runs when the flow sensor indicates the water flow is below
the threshold flow and to stop the engine when the timer
expires.
16. The pressure washer of claim 5, wherein the controller does not
include a microcontroller.
17. The pressure washer of claim 5, wherein the controller is
configured to implement an off delay timer set for a predetermined
amount of time; wherein the off delay timer is started in response
to a change in pressure indicated by the pressure sensor; and
wherein the controller is configured to stop the engine when the
predetermined amount of time is met.
18. A pressure washer comprising: an engine; a water pump driven by
the engine, the water pump providing pressurized water; a starter
motor coupled to the engine to start the engine; an energy storage
device electrically coupled to the starter motor; a spray device
including an activation device for starting and stopping a flow of
water from the spray device; a sensor configured to indicate a
water flow or a water pressure relative to a threshold; and
non-programmable circuitry configured to control the operation of
the engine, the non-programmable circuitry including a starter
motor activation circuit configured to activate the starter motor
to start the engine when the sensor indicates the water flow above
the threshold or the water pressure above the threshold.
19. The pressure washer of claim 18, wherein the sensor comprises a
flow sensor configured to indicate the water flow relative to the
threshold; and wherein the non-programmable circuitry further
includes an off time delay circuit configured to implement a timer
that runs when the flow sensor indicates the water flow is below
the threshold flow and to stop the engine when the timer
expires.
20. The pressure washer of claim 19, wherein the non-programmable
circuitry further includes an on delay timer circuit configured to
implement a timer that delays activation of the starter motor until
the flow sensor indicates the water flow is above the threshold
flow for a predetermined amount of time.
21. The pressure washer of claim 18, wherein the non-programmable
circuitry further includes a crank limiting timer circuit
configured to implement a timer that runs while the starter motor
is activated and to stop the starter motor when the timer expires.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application claims the benefit of U.S. Provisional
Application No. 61/657,607, filed Jun. 8, 2012, which is
incorporated herein by reference in its entirety. This application
is a continuation-in-part of International Application No.
PCT/US2013/035623, filed Apr. 8, 2013, which claims the benefit of
U.S. Provisional Application No. 61/625,437, filed Apr. 17, 2012,
and the benefit of U.S. application Ser. No. 13/692,739, filed Dec.
3, 2012, which is a continuation-in-part of U.S. application Ser.
No. 13/289,613, filed Nov. 4, 2011, all of which are incorporated
herein by reference in their entireties.
BACKGROUND
[0002] The present invention generally relates to internal
combustion engines and outdoor power equipment powered by such
engines, such as lawn mowers, snow throwers, portable generators,
etc. More specifically, the present invention relates to a starter
system and energy storage system for an engine.
[0003] Outdoor power equipment may use an internal combustion
engine to drive a tool of the equipment, such as a rotary blade of
a lawn mower or an axial cam pump of a pressure washer. Typically
the outdoor power equipment includes a brake mechanism that
selectively prevents or stops rotation of the tool. The brake may
stop a flywheel of the engine, correspondingly stopping the
crankshaft and rotating tool coupled to the power takeoff of the
crankshaft.
[0004] Starting the braked outdoor power equipment may be
cumbersome, requiring release of the brake followed by activation
of the engine. For lawn mowers and other types of outdoor power
equipment, release of the brake may include rotating a bail to draw
an inner-wire of a Bowden cable that lifts the brake mechanism.
Then, activation of the engine typically further includes manually
pulling a recoil starter rope or activating an electric starter for
the engine. A need exists for a less-cumbersome and faster process
to start the outdoor power equipment.
[0005] Furthermore, the outdoor power equipment may include the
engine mounted to a frame or a base plate. If an electric starter
is included, the starter motor is typically connected to an
interface on the handle of the outdoor power equipment so that the
operator may activate the starter motor while standing in an
operational position, such as behind the handle. During assembly of
the outdoor power, a power source, control circuitry, and wiring
associated with the starter motor are coupled to the handle, the
frame, and the engine, the attachment of which may be a
time-consuming and labor-intensive process. A need exists for an
engine having a starter motor that facilitates efficient assembly
of the outdoor power equipment.
SUMMARY
[0006] One embodiment of the invention relates to a pressure washer
including an engine, a water pump driven by the engine, a starter
motor coupled to the engine to start the engine, an energy storage
device electrically coupled to the starter motor, a spray device
including an activation device for starting and stopping a flow of
water from the spray device, a pressure sensor, and a flow sensor.
The water pump has a low pressure side and a high pressure side.
The high pressure side provides pressurized water. The pressure
sensor is located at the low pressure side and is configured to
indicate a water pressure relative to a threshold pressure. The
flow sensor is located at the low pressure side and is configured
to indicate a water flow relative to a threshold flow. With the
engine off, the starter motor starts the engine when the pressure
sensor indicates the water pressure is above the threshold pressure
and the flow sensor indicates the water flow is above the threshold
flow.
[0007] Another embodiment of the invention relates to a pressure
washer including an engine, a water pump driven by the engine and
providing pressurized water, a starter motor coupled to the engine
to start the engine, an energy storage device electrically coupled
to the starter motor, a spray device including an activation device
for starting and stopping a flow of water from the spray device, a
pressure sensor configured to indicate a water pressure relative to
a threshold pressure, a flow sensor configured to indicate a water
flow relative to a threshold flow, and a controller configured to
control the operation of the engine. With the engine off, the
controller activates the starter motor to start the engine when the
pressure sensor indicates the water pressure is above the threshold
pressure and the flow sensor indicates the water flow is above the
threshold flow.
[0008] Another embodiment of the invention relates to a pressure
washer including an engine, a water pump driven by the engine, the
water pump providing pressurized water, a starter motor coupled to
the engine to start the engine, an energy storage device
electrically coupled to the starter motor, a spray device including
an activation device for starting and stopping a flow of water from
the spray device, a sensor configured to indicate a water flow or a
water pressure relative to a threshold, and non-programmable
circuitry configured to control the operation of the engine. The
non-programmable circuitry includes a starter motor activation
circuit configured to activate the starter motor to start the
engine when the sensor indicates the water flow above the threshold
or the water pressure above the threshold.
[0009] Another embodiment of the invention relates to method of
controlling an engine of a pressure washer, where, with the engine
off, a starter motor is turned on to start the engine in response
to a detected water pressure above a threshold pressure and a
detected water flow above a threshold flow. In a further
embodiment, the method also includes, with the engine on,
implementing an off delay timer for tracking, up to a predetermined
amount of time, a time for which the detected water flow is below
the threshold flow, and turning the engine off when the
predetermined amount of time is met. In a further embodiment, the
method also includes reducing an engine speed while the off delay
timer is tracking the time. In a further embodiment, the method
also includes determining if the starter motor has successfully
started the engine, and if the engine is successfully started,
turning off the starter motor, and if the engine is not
successfully started, implementing a starter motor cranking timer,
for tracking, up to a predetermined amount of time, a time for
which the engine is not successfully started and turning off the
starter motor when the predetermined amount of time is met.
[0010] Alternative exemplary embodiments relate to other features
and combinations of features as may be generally recited in the
claims.
BRIEF DESCRIPTION OF THE FIGURES
[0011] The disclosure will become more fully understood from the
following detailed description, taken in conjunction with the
accompanying figures, in which:
[0012] FIG. 1 is a perspective view of a lawn mower according to an
exemplary embodiment of the invention.
[0013] FIG. 2 is a perspective view of a handle for outdoor power
equipment according to an exemplary embodiment of the
invention.
[0014] FIG. 3 is a perspective view of a handle for outdoor power
equipment according to another exemplary embodiment of the
invention.
[0015] FIG. 4 is a schematic diagram of a starter system for an
engine according to an exemplary embodiment of the invention.
[0016] FIG. 5 is a perspective view of components of a starter
system for outdoor power equipment according to an exemplary
embodiment of the invention.
[0017] FIG. 6 is a perspective view of an engine assembly according
to an exemplary embodiment of the invention.
[0018] FIG. 7 is a perspective view of a battery charging station
according to an exemplary embodiment of the invention
[0019] FIG. 8 is a perspective view of a battery being coupled to
an engine according to an exemplary embodiment of the
invention.
[0020] FIG. 9 is a perspective view of a starter for the engine
assembly of FIG. 6 according to an exemplary embodiment of the
invention.
[0021] FIG. 10 is a circuit diagram of a controller for a starter
of an engine according to an exemplary embodiment of the
invention.
[0022] FIG. 11 is a circuit diagram of a controller for a starter
of an engine according to another exemplary embodiment of the
invention.
[0023] FIG. 12 is a perspective view of a pressure washer according
to an exemplary embodiment of the invention.
[0024] FIG. 13 is a circuit diagram for a starter system of an
engine according to another exemplary embodiment of the
invention.
[0025] FIG. 13A is a circuit diagram for a starter system of an
engine according to another exemplary embodiment of the
invention.
[0026] FIG. 14 a schematic diagram of the pressure washer of FIG.
12.
[0027] FIG. 15 is a flowchart of a method for controlling the
engine of the pressure washer of FIG. 12.
[0028] FIG. 16 is a schematic diagram of outdoor power equipment
according to an exemplary embodiment of the invention.
[0029] FIG. 17 is a front view of a control module of the outdoor
power equipment of FIG. 16.
DETAILED DESCRIPTION
[0030] Before turning to the figures, which illustrate the
exemplary embodiments in detail, it should be understood that the
present application is not limited to the details or methodology
set forth in the description or illustrated in the figures. It
should also be understood that the terminology is for the purpose
of description only and should not be regarded as limiting.
[0031] Referring to FIG. 1, outdoor power equipment, in the form of
a lawn mower 110, includes an internal combustion engine 112
coupled to a rotary tool, such as the blade in a deck 114 of the
lawn mower 110, an auger, a saw, tines, a drill, a pump, or other
rotary tools. In some embodiments, the lawn mower 110 further
includes wheels 116 and a rearward extending handle 118 designed to
be pushed by an operator walking behind the lawn mower 110. In
other contemplated embodiments, the outdoor power equipment may be
in the form of a rotary tiller, a pressure washer, a snow thrower,
a lawn tractor or riding mower, an edger, a portable generator, or
other equipment, with a corresponding powered tool, such as tines,
a pump, an auger and impeller, an alternator, a drive train, or
other tools.
[0032] Still referring to FIG. 1, the lawn mower 110 includes a
starter system. According to an exemplary embodiment, the starter
system includes an electric motor 120 that is selectively coupled
to the engine 112 such that the electric motor 120 is configured to
rotate the crankshaft of the engine 112 to start the engine 112,
and is then configured to disengage once the engine 112 is running.
In some embodiments, the motor 120 is fastened to the engine 112,
such as being mounted on top of or to a side of the engine 112.
Gearing (e.g., gear reduction, transmission) may extend between the
motor 120 and the crankshaft of the engine 112, or the motor 120
may be connected directly to the crankshaft of the engine 112.
[0033] According to an exemplary embodiment, an operator may engage
the starter system via the handle 118 of the lawn mower 110. In
some embodiments, the handle 118 includes a lever 122, button,
toggle, or other interface that the operator may use to command the
starter system to start the engine 112. In some embodiments, the
command is relayed from the handle 118 via a linkage 124, such as
an electric wire transmitting an electrical signal, a Bowden cable
communicating a mechanical signal, or another type of linkage. In
contemplated embodiments, a transmitter and start button are
coupled to the handle (e.g., clipped on, integrally mounted with),
and the starter system includes an integrated receiver configured
to receive commands wirelessly provided by the transmitter to start
the engine. According to an exemplary embodiment, the command from
the operator is received directly or indirectly by the motor 120,
and the motor 120 rotates the crankshaft to start the engine
112.
[0034] In some embodiments, the starter system is integrated with a
bail 126 of the lawn mower 110. A brake mechanism (e.g., friction
brake, ignition interrupt switch or circuit, etc.) may be holding
the blade or other tool, locking the crankshaft of the engine 112,
or otherwise preventing operation of the power equipment. When the
operator actuates the bail 126 to release the brake mechanism from
rotating members (e.g., blade, crankshaft, power takeoff, flywheel)
of the lawn mower 110, the action simultaneously actuates the motor
120 to start the engine 112. As such, releasing of the brake
mechanism synergistically also starts the engine 112, easing
operation of the lawn mower 110 or other outdoor power equipment by
reducing the steps necessary for activation.
[0035] In some embodiments, the lawn mower 110 includes an
interlock 128 (e.g., lock-out device, signal interrupt) to prevent
release of the brake and engagement of the motor 120. According to
an exemplary embodiment, the operator must release the interlock
128 before the bail 126 can be operated to engage the motor 120 to
start the engine 112. Different types of mechanical and electrical
interlocks may be used in varying contemplated embodiments to
prevent inadvertent release of the brake and starting of the
engine, such as when a user moves the power equipment into or out
of a garage or storage shed by grabbing the handle, or if the bail
is unintentionally bumped. Furthermore, engagement of the interlock
128, in some embodiments, is also configured to prevent inadvertent
release of the brake when the handle 118 is being folded over the
deck 114 to put the lawn mower 110 in a storage configuration.
[0036] In some embodiments, the interlock 128 may prevent a signal
from being sent via the linkage 124 to engage the motor 120 and
release the brake. The interlock 128 may physically disconnect the
linkage 124 from the bail 126, such as by removing a linking pin
that joins the bail 126 to the linkage 124, removing a clamp that
holds the linkage 124 to the bail 126, or otherwise physically
separating the bail 126 and linkage 124. Release of the interlock
128 then physically or electrically connects the bail 126 (or other
brake release) to the controller 132 (e.g., control system, control
circuit, computerized controller) such that operation of the bail
126 is communicated to the controller 132 to simultaneously start
the engine 112.
[0037] In other embodiments, the interlock 128 physically prevents
(e.g., blocks, holds, jams) rotation of the bail 126 when the
interlock 128 is engaged. In some such embodiments, a cam may be
rotated into or out of the path of the bail 126, optionally
preventing rotation of the bail 126. In other such embodiments, a
clamp of the interlock 128 may bind the bail 126 to the handle 118,
preventing rotation of the bail 126 until released. In still other
such embodiments, a sleeve or latch may slide over the bail 126,
holding the bail at a fixed angle until released. The mechanical
interlock described in this paragraph may be used in an embodiment
where no electrical wiring harness on the handle 118 is required to
support the starting of the electric motor 120 and engine 112.
[0038] In contemplated embodiments, an electrical signal may
indicate to the controller 132 that the interlock 128 has been
released, such as a signal communicated via the linkage 124, via
radio frequency communication, hardwired, or otherwise. The signal
is provided in addition to a separate signal associated with
movement of the bail 126. Without the signal indicating release of
the interlock, the signal associated with movement of the bail will
not be sufficient to instruct the controller to start the engine.
The electrical signal may be associated with a pass code, a key, a
scanned finger print, or other access-limiting device.
[0039] According to an exemplary embodiment, the lever 122 (e.g.,
interface, release mechanism, trigger) may serve to release the
interlock 128, allowing operation of the bail 126 to release the
brake and to start the motor 120. In some embodiments, pulling of
the lever 122 may move a physical obstacle out of the rotational
path of the bail 126. In other embodiments, pulling of the lever
122 may mechanically or electrically connect the bail 126 and the
linkage 124. Other mechanisms, such as buttons, switches, toggles,
dials, etc., may serve as release mechanisms to release the
interlock 128. In some embodiments, conventional mechanical
rotational interlocks or electrical switches (e.g., signal
disconnects) are used as the interlock.
[0040] In general, integration of the starter system with a handle
of outdoor power equipment allows the operator to start the engine
from the rear of the outdoor power equipment, such as several feet
from the powered tool of the outdoor power equipment (e.g., snow
thrower auger, lawn mower blades). Further, the integration
supports an electric starting system for a walk behind mower that
can be engaged by a user without actuation of a key or push-button.
In other embodiments, the starter system may include a start button
or other interface to engage the starter system that is located on
the engine or elsewhere. For example, in contemplated embodiments,
such an interface may include a smart phone application or remote
control that wirelessly provides a start command or authorization
code to a receiver coupled to the outdoor power equipment.
[0041] According to an exemplary embodiment, the starter system
further includes an energy storage device 130 (e.g., electrical
storage device) and a controller 132. The energy storage device 130
may include one or more batteries, capacitors, or other devices.
When the operator engages the starter system, the linkage 124
communicates the command to start the engine directly or indirectly
to the controller 132, which electrically connects the energy
storage device 130 to power the motor 120. In some embodiments, the
controller 132 is coupled to a governor of the engine 112 (see,
e.g., speed sensor 420 as shown in FIG. 4), and disengages the
motor 120 (e.g., cuts power to the motor 120, high-side switching
of the battery power source, low-side switching of the ground side
of the circuit) when the engine 112 is running at a sufficient
speed.
[0042] In some embodiments, the motor 120, the energy storage
device 130, and the controller 132 are fastened directly to the
engine 112, which may be configured for efficient assembly of
outdoor power equipment using the engine 112. As such, the starter
system in some embodiments may come fully assembled with the engine
112 and ready for connection to a linkage configured to provide a
signal from the handle (e.g., linkage 124). In some embodiments, an
interface (e.g., start button, toggle, switch) for starting the
engine is positioned on the engine itself, and no additional
connections are necessary--the manufacturer need only attach the
engine to the deck or corresponding feature and attach the tool to
the power takeoff of the engine. In any such case, considerable
time and effort may be saved during the manufacturing process and a
potential source of manufacturing difficulty may be removed (i.e.,
that associated with the fastening and electrical connection of the
components of the starter system during assembly of the outdoor
power equipment). In still other embodiments, some or all of the
starter assembly may be fastened to the deck of a lawn mower or
corresponding feature of other power equipment.
[0043] Referring to FIGS. 2-3, handles 210, 310 for outdoor power
equipment, such as a lawn mower, rotary tiller, snow thrower, etc.,
each include a bail 212, 312 and an interlock 214, 314 with a
release button 216, 316. In contemplate embodiments, the release
button 216, 316 may release the bail 212, 312 from being
interlocked by allowing the bail 212, 312 to move, or by coupling
the bail 212, 312 and linkage 124. In FIG. 2, the release button
216 is to the side of the bail 212, while in FIG. 3, the release
button 316 for the interlock 314 is on top of the bail 312. The
release button 216 of FIG. 2 may disengage a member from blocking
movement of the bail, while the release button 316 may connect the
bail 312 and linkage 124. In other contemplated embodiments,
release buttons or other release mechanisms may be positioned
elsewhere on the handle, the engine, or on another component of the
outdoor power equipment.
[0044] Still referring to FIGS. 2-3, in other contemplated
embodiments, the buttons 216, 316 may be used to provide a signal
directly or indirectly to a motor to start an engine, without
regard to the bail 212, 312. However, integrating the buttons 216,
316 with the bail 212, 312 allows for a two-step process to start
the engine (i.e., release interlock and operate bail), while
synergistically using the operation of the bail 212, 312 to both
release the brake as well as to engage the starter. In still other
embodiments, other forms of interlocks and release mechanisms for
the interlocks may be used, such as a biased lever (see lever 122
of interlock 128 as shown in FIG. 1), latch, thumb-print reader,
etc.
[0045] In some embodiments, a three-step process is used to engage
the power equipment, such as first disabling or releasing an
interlock; second presenting a key, a code, or other device to
release an access-control mechanism (e.g., lock out, lock); and
third pulling the bail. In alternate embodiments, the key hole or
interface for the access-control mechanism may be positioned on the
handle or on the engine.
[0046] Referring to FIG. 4, outdoor power equipment 410 (shown
schematically) includes an engine 412 and a powered tool 414 (e.g.,
rotary blade) driven by the engine 412. In some embodiments, a
motor 416 is coupled to the engine 412, and the powered tool 414 is
coupled to a power takeoff 418 of the engine 412. A speed sensor
420 (e.g., governor) may be coupled to the engine 412 to regulate
the speed of the engine 412. Also, a brake 422 may be coupled to a
rotary member of the outdoor power equipment 410, such as the
flywheel of the engine, the power takeoff 418 of the engine, etc.,
to stop the engine as well as the associated powered tool.
[0047] In some embodiments, the outdoor power equipment 410
includes a handle 424 having a release mechanism 426, where the
release mechanism 426 is configured to allow a user to release the
brake 422 from the handle 424. The release mechanism 426 may allow
a user to release the brake 422 by engaging the bail (or other
element) with a linkage connected to the brake 422, or by
disengaging an element blocking movement of the bail. The handle
424 may be coupled to the engine 412 and tool 414 directly, or via
an intermediary member (e.g., deck 114 as shown in FIG. 1). The
engine 412 may further include a battery 428 for powering the motor
416 and a control system 430 for operating the motor 416.
[0048] According to an exemplary embodiment, the control system 430
is configured to receive inputs associated with the release
mechanism 426. In some embodiments, when the release mechanism 426
is actuated to release the brake 422, the release mechanism 426
triggers a switch 432, which provides to the control system 430 a
signal that is indicative of the release of the brake 422. The
signal may be provided via a mechanical linkage, wirelessly, a
hardwired electrical connection, or otherwise. In some embodiments,
the control system 430 then actuates the motor 416 to start the
engine 412 or uses the information in control logic configured to
start the engine as a function of the status of the brake and other
factors. As such, operation of the release mechanism 426 may
simultaneously provide a start signal to the control system 430 as
well as release the brake 422. No additional operations to start
the engine 412 may be required.
[0049] According to an exemplary embodiment, the control system 430
is configured to receive additional inputs from the speed sensor
420 or another component of the engine 412 (e.g., ignition
circuit). The speed sensor 420 or other component provides the
control system 430 with information associated with the speed of
the engine 412. When the engine 412 is running at a sufficient
speed, the control system 430 then disengages the motor 416 (e.g.,
turns off, disconnects, cuts power to, etc.).
[0050] In contemplated embodiments, the control system 430
associated with the start system may receive additional or
different inputs used to control starting of the engine, such input
from a sensor configured to indicate whether the outdoor power
equipment has moved recently. Movement of an axle or wheels of such
outdoor power equipment may trigger a sensor that provides a signal
to the control system. The signal, in combination with an electric
timer providing time-related context for the movement, may serve as
an additional indicator that the operator intends to activate the
engine. In contemplated embodiments, the control system 430
includes a timer and is configured to deactivate the motor if the
engine has not started within a predetermined amount of time. In
some contemplated embodiments, the control system 430 includes a
temperature sensor and is configured to prime the engine with an
automated primer pump or adjust the choke or throttle plate if
ambient temperature is above or below a predetermined temperature,
if a portion of the engine is above or below a predetermined
temperature, or if the difference between ambient and engine
temperature is above or below a predetermined amount. In
contemplated embodiments, the control system 430 may also provide a
signal output to the operator, such as a visible indicator on a
display coupled to the handle or engine, or an audible alert. In
some such embodiments, the signal output may include as an error
message, a low-fuel message, a replace-oil message, or another such
message.
[0051] Referring to FIG. 5, components of a system 510 include a
brake cable 512 (e.g., Bowden cable) and a brake pad 514 for an
associated engine of outdoor power equipment. According to an
exemplary embodiment, the brake cable 512 is configured to be
coupled to the bail of a handle of outdoor power equipment (see,
e.g., bails 126, 212, and 312 as shown in FIGS. 1-3). When an
operator activates the bail, the brake cable 512 moves a pivot 516
coupled to the brake pad 514. The brake pad 514 then releases,
allowing the engine associated with the system 510 to drive a
powered tool of the outdoor power equipment.
[0052] According to an exemplary embodiment, the engine associated
with the system 510 further includes a starter system including a
switch 518, an electronic control 520, a battery 522, and an
electric starter motor 524. When the operator activates the bail to
lift the brake pad 514, the pivot 516 simultaneously activates the
switch 518. The switch 518 then provides a signal to the electronic
control 520 that the brake pad 514 has been lifted and that the
electronic control 520 may start the engine associated with the
system 510 with the electric starter 524. The electronic control
520 then connects the electric starter 524 to the battery 522. The
switch 518 may be a switch already associated with the brake, but
used to provide signals to both an actuator of the brake and the
starter system (e.g., ignition ground), or the switch 518 may be an
additional switch solely used for the starter system.
[0053] Still referring to FIG. 5, the electronic control 520
includes hard-wired circuitry and is configured to receive
additional inputs from the engine associated with the system 510.
In some embodiments, the additional inputs include an indication of
the speed of the engine associated with the system 510 from a
governor or other component of the engine (e.g., electrical pulses
from the ignition system). The additional inputs may include a
current state of the engine associated with the system 510, such as
whether the engine associated with the system 510 is running, etc.
The starter system is also coupled to a ground 526.
[0054] Referring to FIGS. 6-9, an engine 610 includes an exhaust
612, a fuel tank 614, an engine cover 616, an air intake 618 for
combustion processes, an air intake 620 for cooling the engine, and
a starter system having an energy storage device, such as a battery
622 (e.g., lithium-ion, lead-acid, etc.), a capacitor, multiple
batteries or capacitors, or another energy storage device.
Applicants note that the engine 610 of FIGS. 6-9 mirrors the engine
112 of FIG. 1, and both are single-cylinder, four-stroke cycle,
vertically-shafted, small engines. Other engine types and designs
may be used, such as engines that are horizontally-shafted, two- or
more cylindered, diesel powered, cold-weather structured, etc.
[0055] Although shown as proximate to the fuel tank 614 and exhaust
612 in FIGS. 6 and 8-9, the energy storage device may be positioned
elsewhere on the exterior and/or in an internal port of the engine
610. In some embodiments, where the energy storage device is
sensitive to high temperature, it may be preferred to position the
energy storage device away from the exhaust 612, which may become
hot during operation of the engine 610.
[0056] According to an exemplary embodiment, the energy storage
device 622 is configured to power a starter motor (see, e.g., motor
120 as shown in FIG. 1) integrated with the engine 610. In some
embodiments, the energy storage device may be further configured to
power other systems of the engine 610, such as an engine control
unit (ECU) having control circuitry coupled to sensors or detectors
integrated with the engine (e.g., brake release, fuel-level
detector, ignition-fouling detector, governor, etc.).
[0057] According to an exemplary embodiment, the energy storage
device is the battery 622, which is rechargeable. As shown in FIG.
7, the battery 622 may be charged at a charging station 624 or may
include a charging port integrated with the battery (e.g., battery
pack with charging port to receive a connection from a wire coupled
to an outlet or the charging station). The battery 622, in other
embodiments, may alternatively plug directly into a wall outlet, or
the charging station may be wall mounted or plug directly into a
wall outlet.
[0058] In some embodiments, the energy storage device is or
includes a bank of capacitors, where the capacitors are configured
to charge and release electrical energy in a relatively short
(e.g., less than 10 seconds), high-powered output. In some such
embodiments, some of the capacitors of the bank are coupled with
one another in groups (e.g., series or parallel), and the groups
are configured to output sequentially in time with respect to one
another. Accordingly, the capacitors are specifically configured to
be able to power the motor to start the engine 610 without much
additional energy storage capacity so as to be relatively compact
in size and inexpensive. Use of capacitors may also allow for
faster charging when compared to batteries, such as faster charging
on the charging station 624 (FIG. 7).
[0059] In contemplated embodiments, the starter motor is configured
to draw power from the engine 610, such as during periods of lesser
loads on the engine. The starter motor is then driven by the engine
610 to provide an electric output. The electric output may then be
routed by the ECU or otherwise to charge the energy storage device.
Such a system may be particularly useful for an engine driving an
alternator of a portable generator, where the alternator may
temporarily be powered by the energy storage device to start the
engine and then, once the engine has started, the alternator may be
used to recharge the energy storage device.
[0060] Referring to FIG. 8, the battery is configured to be
inserted (e.g., dropped, lowered, placed) into a receiving port 626
integrated with the engine. Integrating the receiving port with the
engine reduces the assembly burdens for manufacturing outdoor power
equipment, as disclosed above. However in contemplated embodiments,
the receiving port may not be integrated with the engine. For
example, FIG. 7 shows a charging station 624 or charging port,
which may be similar to such a port on a deck of the engine.
[0061] In some embodiments, the battery 622 has a cross section
forming an isosceles trapezoid, triangle, diamond, or other wedge
shape, or shape having a narrower lower portion 628 relative to an
upper portion 630 in contact with the receiving port 626. The
receiving port 626 is contoured (e.g., V-shaped, U-shaped, etc.) to
receive the battery 622, which may be guided into position by
interfacing with the contours of the receiving port 626 and
gravity.
[0062] In some embodiments, the battery 622 includes slots or grips
632 for lifting and holding the battery 622. A locking mechanism,
such as a hook or latch may snap into place when the battery 622 is
inserted into the receiving port 626 and hold the battery 622 in
the receiving port 626. Pinching the grips 632 together may release
the locking mechanism to allow removal of the battery 622 from the
receiving port 626.
[0063] According to an exemplary embodiment, the starter system
further includes a switch 636 (e.g., toggle, lever, key) that is
integrated with the battery 622, the receiving port 626, or
elsewhere on the engine 610. As shown in FIGS. 8-9, the switch 636
may rotate from an off position (FIG. 8), where the battery 622 is
not electrically connected to components of the engine 610 (e.g.,
starter motor, ECU), to an on position (FIG. 9), where the battery
622 is electrically connected to the components. In other
embodiments, rotation of the switch 636 also or alternatively
engages the locking mechanism to hold the battery 622 in the
receiving port 626. In various contemplated embodiments, the switch
636 may be configured to interrupt electrical connectivity of the
battery, the control circuit, or both.
[0064] According to an exemplary embodiment, the starter system
includes an interface, shown as a button 634 on the receiving port
626. In other exemplary embodiments, the starter system may include
another type of interface, such as a toggle switch, a rocker
switch, a capacitive switch, etc. The interface, such as the button
634, may be located on the engine 610 and face outward and is
accessible when the battery 622 is seated in the receiving port
626. In some embodiments, the interface allows the operator to
start the engine via the starter system. In other embodiments, the
interface may be used to initiate charging of the battery or
another function.
[0065] Referring now to FIGS. 12 and 14, a pressure washer 710
includes a frame 711 supporting an engine (e.g., the engine 610
shown in FIGS. 6-9), and a water pump 713 (e.g., positive
displacement pump, piston water pump, axial cam pump) configured to
be connected to a spray gun 714 (e.g., spray gun, spray wand,
brush, other spray device, etc.) with a delivery hose or conduit
715 (e.g., a high-pressure hose). In some embodiments, the engine
610 is fastened to the top of a base plate of the frame 711 and the
water pump 713 is mounted below the base plate and connected to the
engine 610 via a hole through the base plate. In other embodiments,
the water pump 713 is directly coupled to and supported by the
engine 610. The water pump 713 is coupled (e.g., directly coupled,
indirectly coupled by a transmission, belts, gears, or other drive
system) to the engine 610 to be driven by the engine 610. In some
embodiments, the pressure washer 710 is portable and includes
wheels 717 and a handle 718. In other embodiments, the pressure
washer 710 may be stationary. In other embodiments, the pressure
washer 710 is mounted to a trailer or other vehicle. The water pump
713 includes a pump inlet 719 and a pump outlet 721. The pump inlet
721 is configured to be coupled to a supply conduit or hose 723,
which is in turn connected to a fluid supply 725 (e.g., a spigot
connected to a municipal water supply or well). In some
embodiments, the pump inlet 719 includes a low-pressure,
garden-hose style fitting for coupling a garden hose to the pump
inlet 719. The pump outlet 721 includes a high-pressure fitting
(e.g., an M22 fitting) for coupling the pump outlet 721 to the
delivery hose 715 or other device including an appropriate high
pressure fitting. As shown in FIGS. 12 and 14, pressure washer 710
uses a vertical shaft engine. According to an alternative
embodiment, the engine may be a horizontal shaft engine.
[0066] In some embodiments, an operator may press the button 634 to
start the engine 610. In some embodiments, the motor 120 is a
motor/generator that may provide power to charge the battery 622 of
the starter system when operating in the generator mode. According
to an exemplary embodiment shown in FIG. 12, the battery 622 is
coupled to the engine 610. According to another exemplary
embodiment, the battery 622 is coupled to the frame 711 or other
location on the pressure washer 710 other than the engine 610.
[0067] As pressure washer 710 does not have a bail similar to bails
126, 212, 312 shown in FIGS. 1-3, the electrical switch associated
with the button 634 may be more complex than that used in lawnmower
applications utilizing a bail. That is, in some of the lawnmower
configurations described herein, a single-pole-single-throw switch
is used to send power (e.g., 12 volts) to power up and start the
engine when the user pulls the bail, and then removes the power
(e.g., 12 volts) and shorts the ignition to ground when the user
releases the bail, thus stopping the engine. However, on non-mower
applications that do not use a bail, either a
double-pole-double-throw switch or other solid state electronics
may be used to ground the ignition on one pole when in the OFF
position, and sends power (e.g., 12 volts) to the second pole when
in the ON position. In this way, one position removes the power
(e.g., 12 volts) and shorts the ignition (OFF), while the other
position un-shorts the ignition and applies the power (e.g., 12
volts) (ON).
[0068] As an alternative or in addition to the button 634 or other
interface of the starter systems described above, and in accordance
with another exemplary embodiment, engine 610 of pressure washer
710 may be started via actuation of a trigger 712 on the spray gun
714 shown in FIG. 12. Such trigger-start control systems and other
control systems described herein (e.g., the circuits shown in FIGS.
10-11, 13, and 13A and the method shown in FIG. 15) may be
implemented as "non-programmable circuitry" that consists of analog
or digital hard circuitry that does not utilize a microcontroller
or software. It is believed that embodiments in which the controls
are implemented as non-progammable circuitry including discrete
components may be less expensive than embodiments implemented with
microcontrollers or using software. Such non-programmable circuitry
embodiments do not include a microcontroller.
[0069] An example circuitry schematic in accordance with the
proposed embodiment is illustrated in FIG. 13. Block 734 shown in
FIG. 13 represents the same starter system circuitry as is
illustrated in FIG. 11. The present embodiment related to pressure
washer 710 requires additional circuitry to function effectively.
For instance, block 735 acts as a starter motor cranking limiter,
which limits the amount of time the starter motor 120 can crank
without the engine 610 starting. Block 736 represents a flow sensor
and/or a pressure sensor, which senses water flow or pressure,
respectively, through the system, as will be discussed further
herein. Block 737 represents an ON time delay circuit, which
detects the amount of time that a user has actuated trigger 712 and
prevents starting of the engine 610 if a predetermined time period
has not elapsed (e.g., during incidental user contact with trigger
712). Block 743, on the other hand, represents an OFF time delay
circuit, which allows the engine to continue running for a
predetermined period of time after the user has released trigger
712. Following the expiration of this timer, the engine 610 is
turned off. Block 743 may contain a connection to a device (e.g., a
potentiometer, dial, keypad, touchscreen, other user input device)
which allows for user customization of the OFF time delay. The
user-set OFF time delay may be infinitely variable across a range
of values or variable in preset units (e.g., 1 second, 5 seconds,
10 seconds, 15, seconds, 30 seconds, 1 minute). Block 739
represents a manual stop override input (e.g., via an enable key
insert, button, keyswitch, toggle switch, other user input device)
for the OFF time delay, which allows a user to deactivate the OFF
time delay and immediately disable the engine by grounding the
ignition. Finally, block 741 represents circuitry that detects when
the starter motor is turning, but there is no indication from the
engine (e.g., the flywheel or ignition) that the engine is turning.
This condition may indicate that the pinion gear has improperly
disengaged from the engine's flywheel gear (i.e., a pinion gear
"kickout") or that something is preventing the engine from turning.
After detecting this condition, the circuitry may be configured to
either automatically reinitialize the starting process or stop the
starting process until the user reinitializes the starting process.
The overall operation of the starter system represented by the
circuitry shown in FIG. 13 will be discussed below. Although FIG.
13 illustrates a circuit for use with a specific type of ignition
coil, the circuit may be modified to accept universal ignition
coils or any other appropriate type of ignition coil. Additionally,
the electric starter system shown in FIG. 13 or any of the other
electric starter systems described herein may include provisions
allowing for the use of a manual starter. The manual starter (e.g.,
a recoil starter, a rope-pull starter, etc.) allows the user to
manually start the engine in the event of insufficient battery
voltage to power the starter motor or if a removable battery cannot
be located for use with the outdoor power equipment.
[0070] FIG. 13A illustrates an alternative version of
non-programmable circuitry for implementing a trigger-start
operation of a pressure washer. The non-programmable circuitry
include multiple discrete components that implement the various
operations described in more detail below and elsewhere in the
application. A starter motor activation circuit (block 900) allows
for trigger starting a pressure washer based on inputs from a flow
sensor and a pressure sensor (block 905). Alternatively, a flow
sensor is used alone or a pressure sensor is used alone as
explained elsewhere. The flow sensor and the pressure sensor
provide signals that indicate when the detected flow and pressure,
respectively, are above a threshold. The flow sensor and the
pressure sensor may be arranged in series or in parallel. An on
delay timer circuit (block 910) requires that the flow sensor
detects flow above the threshold and the pressure sensor detects
pressure above the threshold for a predetermined amount of time
before the starter motor activation circuit provides a signal to
crank (e.g., start, turn on, etc.) the starter motor. Crank
limiting timer circuit (block 915) allows the starter to crank for
a predetermined amount of time (e.g., 10 seconds). When the timer
expires, cranking is stopped (e.g., the starter motor is stopped,
turned off, etc.). Crank limiting timer reset circuit (block 920)
resets the timer of the off time delay circuit (block 925) when the
user stops the cranking operation (e.g., by releasing the trigger
on the spray gun) while the timer of crank limiting reset circuit
(block 920) is running. This helps to ensure that the timer of the
crank limiting timer circuit (block 920) is able to run for the
full amount of time each time the user initiates the process to
crank the starter motor.
[0071] An off time delay circuit (block 925) stops the engine
following the expiration of a predetermined amount of time. The
timer begins to run when the detected flow drops below the
threshold, stops when the detected flow rises above the threshold,
and restarts when the detected flows drops below the threshold
before the predetermined amount of time is met. In some
embodiments, pressure sensing is used in addition to or in place of
flow sensing, with the timer started, stopped, and reset in
response to changes in detected pressure and/or detected pressure
relative to one or more threshold pressures. Engine stop circuit
(block 930) stops the engine by shorting the ignition. Engine stop
circuit (block 930) may receive inputs to stop the engine from the
off time delay circuit (block 925), a user interface (e.g., button,
switch, etc., like the rocker switch associated with off timer
bypass circuit 940), or from the starter motor lockout circuit
(block 960). Off time reset circuit (block 935) resets the timer of
the off time delay circuit (block 925) when the user releases the
trigger while the starter motor is cranking, but the engine is not
yet running. An off timer bypass circuit (block 940) allows the
user to manually stop the engine without waiting for the timer of
the off time delay circuit (block 925) to expire. The off timer
bypass circuit (block 940) also resets the timer of the off time
delay circuit (block 925) to allow the user to initialize a restart
without having to wait for this timer to expire. In some
embodiments, a rocker switch having three positions (i.e., trigger
start, manual start, off) provides the input to the off timer
bypass circuit 940.
[0072] Ignition speed sensing circuit (block 945) converts an
output from any appropriate type of ignition coil to a signal
usable as engine speed indication. The ignition speed sensing
circuit (block 945) allows multiple types of ignition coils to be
used with pressure washers or engines equipped with the circuitry
of FIG. 13A without having to modify the circuitry to accommodate
each type of ignition coil. Cranking may be stopped (i.e., the
starter motor is turned off) when the engine reaches a threshold
speed.
[0073] Power for the starting system is supplied by a rechargeable
battery. In some embodiments, the battery is removable from the
pressure washer or engine. The rechargeable battery can be
recharged by a charging unit (block 950) or by trickle charging
with excess or waste energy from the ignition coil (block 955).
Starter motor lockout circuit (block 960) prevents the starter
motor from cranking under three conditions. First, it prevents the
starter motor from restarting until the engine has come to a stop
(e.g., the flywheel has stopped spinning). Second, it prevents the
starter motor from cranking when the charging unit is charging the
battery (e.g., plugged in). Third, it shuts off the running engine
when the charging unit is plugged in to charge the battery. This
helps to prevent damage to the charging unit. An LED, light, or
other indicator (block 965) is activated when the engine is
running.
[0074] Referring to FIG. 14, which shows pressure washer 710
schematically, spray gun 714 is connected to the outlet 721 of the
water pump 713 via hose 715 (i.e., fluidly coupled), wherein the
inlet 719 of the water pump 713 is connected to a fluid supply 725
via another hose 723 (i.e., fluidly coupled). The spray gun 714
includes a trigger 712 that actuates a valve in the spray gun 714
to control the flow of fluid through the spray gun 714. Although
illustrated as a lever, the trigger 712 encompasses all types of
appropriate activation devices, including buttons, switches, knobs,
dials, touch pads, touch screens, touch sensors, etc. In a first
position of the trigger 712, the valve is open, and in a second
position, the valve is closed. With the fluid supply 725 connected
to the water pump 713, actuation of trigger 712 allows at least a
small amount of water to flow through the spray gun 714 and the
water pump 713, even when the engine 610 and the water pump 713 are
not operating. A flow sensor 727 (e.g., flow sensor, flow switch,
flow transducer, etc.) and a pressure sensor 729 (e.g., pressure
sensor, pressure switch, pressure transducer, etc.) are used to
sense the flow and pressure, respectively, within the fluid system.
A manual starter 730 (e.g., a recoil starter, a pull-rope starter,
etc.) allows the user to manually start the engine 610 if desired.
In some embodiments, the manual starter 730 is omitted.
[0075] In some embodiments, the flow or pressure sensor comprises a
sensor or transducer that generates a variable signal (e.g.,
resistance, current, voltage, etc.) in proportion to the sensed
value of flow or pressure (e.g., an analog sensor). Such an analog
sensor may be used to compare the detected flow or pressure to a
threshold flow or pressure. In some embodiments, the flow or
pressure sensor comprises a binary switch that turns on and off in
response to a comparison of the detected flow or pressure to a
predetermined threshold. When the trigger 712 is actuated, the flow
sensor 727 detects a flow of fluid through the fluid system
relative to a threshold flow (e.g., above a threshold flow, below a
threshold flow, etc.) at the flow sensor location and the pressure
sensor 729 detects a pressure of the fluid relative to a threshold
pressure (e.g., above a threshold pressure, below a threshold
pressure, etc) at the pressure sensor location. The flow sensor 727
and the pressure sensor 729 communicate with the starter system
(e.g., control circuitry and starter motor) to start the engine 610
when the threshold flow and pressure are detected. Alternatively,
rather than both flow and pressure being used as inputs to the
starter system, flow alone (e.g., via one or more flow sensors) or
pressure alone (e.g., via one or more pressure sensors) may be used
as inputs to the starter system for initializing the starting
process and/or the stopping process.
[0076] The fluid system includes the supply hose 723, the pump
inlet 719, the water pump 713, the pump outlet 721, the delivery
hose 715, and the spray gun 714. The flow sensor 727 and the
pressure sensor 729 may be positioned at any appropriate location
within the fluid system. In some embodiments, the flow sensor 727
(e.g., either self-contained or integrated within the water pump
713) may be placed between the fluid supply 725 and the pumping
mechanism (i.e., the low pressure side) or between the pumping
mechanism and the spray gun 714 (i.e., the high pressure side). In
other embodiments, one or both of the flow sensor 727 and the
pressure sensor is included in the spray gun 714. As illustrated in
FIG. 14, the flow sensor 727 and the pressure sensor 729 are
located on the low pressure side of the fluid system (e.g., at or
near the pump inlet 719). In some embodiments, the flow sensor 727
and the pressure sensor 729 are located on the high pressure side
of the fluid system. In other embodiments, one of the flow sensor
727 and the pressure sensor 729 is located on the low pressure side
and the other is located on the high pressure side.
[0077] In some embodiments, once the pressure sensor 729 detects
the threshold pressure and the flow sensor 727 detects the
threshold flow, the engine 610 can be started using the same logic
as the push-button starter system described in previous
embodiments. For example, the starter system may be arranged so
that the pressure sensor 729 checks for a pressure above a
threshold pressure (e.g., 20 psi, 25 psi, 30 psi, 35 psi, 40 psi,
or other expected pressure from the fluid supply) indicative of
sufficient fluid being available to run the water pump 713 and
then, after checking for the threshold pressure, starts the engine
610 in response to the flow sensor 727 detecting a fluid flow above
the threshold flow (e.g., 0.1 gpm, 0.2 gpm, 0.3 gpm, 0.4 gpm, 0.5
gpm, or other expected flows from the fluid supply when the fluid
is allowed to flow through the spray gun 714) indicative of fluid
flow through the spray gun 714.
[0078] In some embodiments, the pressure sensor 729 is omitted and
only flow sensing is used. In some of these embodiments, one or
more flow sensors 727 detect fluid flow relative to a threshold
flow at the flow sensor location. Alternatively, one or more analog
flow sensors are used that provide a signal indicative of an actual
flow value (e.g., in gpm), rather than detecting flow using a
binary on/off-style flow switch. For example, in some embodiments,
a single flow sensor 727 on the low pressure side of the fluid
system is used to detect flow relative to a threshold flow so that
the engine 610 is started when the detected flow is above the
threshold and the engine 610 is stopped when the detected flow is
below the threshold and/or at zero flow. In some embodiments, a
start delay timer is included that requires the detected flow to be
above the threshold for a predetermined amount of time (0.5
seconds, 1 second, 1.5 seconds, 2 seconds, etc.) before starting
the engine 610. Alternatively, a single flow sensor 727 on the high
pressure side could be used, but a flow sensor suitable for use at
higher pressures would typically need to be more robust, and
therefore more complex and/or expensive, than a flow sensor
suitable for use at lower pressures. In some embodiments, the flow
sensor 727 is omitted and only pressure sensing is used. If
pressure sensing is used, two pressure sensors 729 may be used, one
located at the pump inlet 719 and the other at the pump outlet 721.
In some of these embodiments, one or more pressure sensors 729
detect fluid pressure relative to a threshold pressure. For
example, in some embodiments, pressure sensor 729 is used to detect
fluid pressure so that engine 610 is started when the detected
pressure is below a first threshold pressure (i.e., in response to
the drop in pressure caused when the valve in the spray gun 714 is
opened) and stopped when the pressure sensor 729 detects a pressure
above a second threshold pressure (i.e., in response to a pressure
spike indicative of the valve in the spray gun 714 being closed).
Such pressure sensing could occur on either the low pressure side
or the high pressure side. Depending on the location of the
pressure sensor 729, the pressure drop or spike to be sensed, may
be relatively large, small, or tiny. For example, implementing this
sensing on the low pressure side typically would require a
sophisticated pressure sensor capable of detecting relatively small
changes in pressure. Alternatively, a pressure differential sensor
may be used to measure the pressure difference across the water
pump 713 (e.g., between the pump inlet 719 and the pump outlet 721)
and to provide inputs to the starter system to start and stop the
engine 610 in response to the detected pressure differential.
[0079] Alternatively, a switch could be directly engaged by
actuation of the trigger 712 to start the engine 610, wherein an
electrical connection (e.g., wires) runs between the switch and the
starter system (e.g., control circuitry and starter motor) for the
engine 610 along or through the delivery hose 715. Alternatively, a
switch could be directly engaged by actuation of the trigger 712 to
start the engine 610, wherein wireless communication (e.g., radio
frequency (RF), Infrared (IR), Bluetooth, or other form of wireless
communication) is used between the switch and the starter system
(e.g., control circuitry and starter motor) of the engine 610.
[0080] During connection of the fluid supply 725 to the water pump
713 and subsequent filling of the water pump 713, the flow sensor
727 and/or the pressure sensor 729 may sense a short-duration flow
of water or a pressure change before the trigger 712 is actuated.
Therefore, in some embodiments, the engine 610 does not start
immediately upon sensing flow or pressure change. Instead, a timed
delay start (e.g., 0.5-3 seconds) could be provided by the starter
system circuitry described above. For example, the timed delay
start could be established via a timer, resistor-capacitor circuit
(RC circuit), or equivalent. The timed delay start would eliminate
the possibility of unintentional engine starting. In some
embodiments, the duration of the timed delay start is adjustable by
the user (e.g., via a user input device).
[0081] Similarly, it may not be desirable for engine 610 to stop
(i.e., turn off) immediately upon user release of trigger 712.
Instead, a timed delay stop (e.g., 1-2 minutes) could be provided
by the starter system circuitry described above. For example, the
timed delay stop could be determined by a timer, counting engine
ignition pulses after release of trigger 712, or established via a
resistor-capacitor circuit (RC circuit) or equivalent. If an RC
circuit is used, a user-adjustable timed delay stop could be
provided if a variable resistor (i.e., rheostat) is used. In this
way, engine 610 is not unnecessarily shut down when the user only
briefly releases trigger 712, thereby avoiding overly-frequent
restarts of engine 610 during operation. Such a timed delay stop
could also be used in combination with an automatic throttle
control mechanism to lower engine speed and reduce noise and fuel
consumption during the timed delay. If the user wishes to shut down
engine 610 before the timed delay period expires, a manual stop
button 731 (e.g. push button, toggle switch, other user interface)
is provided. Similarly, a manual start switch (e.g., button 634)
could also be added to engine 610 to serve as an optional or
back-up start system to the trigger-actuated engine starting
system.
[0082] In some embodiments, the engine 610 is stopped in response
to a detected change in engine load and/or speed, rather than, or
in addition to, a detected change in flow and/or pressure. For
example, when the engine 610 is running and the trigger 712 is
pulled to allow flow through the spray gun 714, the engine load
increases and the engine speed decreases due to the increased load
(restriction) on the pump 713. The increased engine load results in
increasing the throttle (e.g., opening the throttle valve). When
the trigger 712 is subsequently released, the engine load decreases
and the engine speed increases due to decreased load (restriction)
on the pump 713. The decreased engine load results in decreasing
the throttle (e.g. closing the throttle valve). Because of the
changes in throttle position, engine load, and engine speed in
response to the trigger state (i.e., open or closed), the change in
engine load and/or engine speed can be used as an input for turning
off the engine 610. This can be accomplished by detecting movement
of the throttle valve or an associated throttle linkage and/or
detecting the change in engine speed with a speed sensor (e.g., via
ignition pulses, speed sensor 820 described below, or other
appropriate sensor for detecting engine speed). The detection can
be accomplished by various types of switches, including proximity
switches, limit switches, magnetic reed switches, snap action
switches, etc. Detecting the movement of the throttle from open to
closed with a switch or detecting the change in engine speed with a
speed sensor could either directly turn off the engine 610 or start
an off delay timer similar to those described elsewhere in the
application. A flow sensor 727 indicating that the detected flow is
below the threshold flow, a switch detecting the movement of the
throttle from open to closed, a speed sensor detecting the change
in engine speed, and/or a pressure sensor 729 detecting an
appropriate change in pressure (e.g., above or below a threshold)
are ways of detecting a stopped flow or zero flow condition. A
running engine 610 may be stopped in response to detecting a
stopped flow condition with any of these methods.
[0083] An additional advantage of the timed delay stop feature is
potential elimination of the need for a thermal bypass system in
the pump. In conventional pressure washer systems, when the trigger
is released while the engine is running, the water in the pump
recirculates under pressure. This condition causes the
recirculating water in the pump to become increasingly hot over
time. Excessively hot water may cause permanent damage to the pump
components. To resolve this problem, most conventional pressure
washers are equipped with a thermal bypass system. When the water
temperature reaches a critical temperature (typically 140.degree.
F.), the thermal bypass system bleeds the high temperature water
out of the pump and to the ground. After cool water enters the pump
and reduces the recirculating water temperature, the thermal bypass
system halts the hot water bleed-off. If the timed delay stop
described above is set shorter than the time required for the
recirculating water in the pump to reach critical bleed-off
temperature (typically 90 seconds), then a thermal bypass system
would not necessarily be required.
[0084] Another advantage of the trigger-actuated engine starting
system described above may be a decreased reliance on a
pressure-relieving unloader valve during engine start-up. In
conventional pressure washer systems, water is provided to the
water pump prior to engine start-up and before the spray gun's
trigger is actuated, creating a pressure within the water pump that
must be relieved by an unloader valve in order to ease engine
starting. However, with the trigger-actuated engine system
described above, this unloader valve could be eliminated, as the
trigger actuation itself relieves the water pressure built up
within the water pump (via initiating water flow) prior to the
engine being started.
[0085] Yet another advantage of the trigger-actuated engine
starting system described above may be decreased pump damage caused
by a user manually starting the pump without the water source
connected to the pump inlet. In conventional pressure washer
systems, the engine can be manually started regardless of whether
the operator has connected the water source to the pump inlet. If
the pump is run without a water supply, the pump may be permanently
damaged in a short period of time (e.g., 30 seconds) due to high
internal friction and temperatures. Using the trigger-actuated
starting system described above, the engine cannot be started
unless a water source is connected to the pump inlet, as water flow
(and/or pressure) must be sensed by a flow sensor (and/or pressure
sensor) to enable starting.
[0086] In accordance with the embodiments described above, a
trigger-actuated engine starting system may reduce fuel consumption
and eliminate noise generated by a gas pressure washer system when
not in use, as needless engine operation can be avoided when the
user is not directly activating the trigger to spray water.
[0087] Referring to FIG. 14, in some embodiments, the
trigger-actuated engine starting system may further include a
removable disable device 733. The removable disable device 733 is
configured to disable (e.g., stop, turn off, etc.) operation of the
engine 610 if the user is not in proximity to the pressure washer
710. For example, the removable disable device 733 may be provided
in the form of a card, medallion, fob, or other device held or
otherwise attached to the user (e.g., with a wrist band, clip,
etc.). The removable disable device 733 is coupled to a socket or
port 735. This coupling can be physical (e.g. by a tether, cable,
cord, chain, etc.) or electronic (e.g., by a wired conductor or
wirelessly). The port 735 may be located on the body of the
pressure washer 710 (e.g., on the frame 711 or the engine 610) or
on the spray gun 714. If the user moves far enough away from the
port 735 to decouple the removable disable device 733 from the port
735, an electric circuit is broken to turn off the engine 610 or a
signal is generated to turn off the engine 610.
[0088] Referring again to FIG. 13, block 744 allows for an outlet
capable of trickle charging battery 622 through the use of excess
ignition energy may be included. According to one exemplary
embodiment, the battery 622 may be charged through the use of
ignition primary pulses. The running state/engine speed/rpms of
engine 610 are conventionally monitored by reading ignition primary
pulses, wherein each ignition primary has a sequence of positive
and negative pulses. The excess ignition energy (e.g., positive
primary pulses) is not needed/used for production of a spark to
fire the engine, so the energy/current from the positive primary
pulses may be used for other uses (e.g., monitoring the rpms). In
this instance, there is enough energy from the positive primary
pulses to both monitor the engine's rpms and trickle charge battery
622. Thus, after the engine 610 has run for a certain period of
time (e.g., 12-15 minutes, more or less time as appropriate), the
positive primary pulses provide enough energy to replenish the
energy used during one starting/cranking cycle, thereby eliminating
the need for the user to recharge battery 622 via other means.
Alternatively, the battery 622 may be charged by the engine
alternator, the starter motor running in a generator mode, or
harvesting energy from engine vibration or thermal energy created
by operation of the engine and/or pressure washer.
[0089] FIG. 15 illustrates an exemplary method 740 for controlling
the engine of a pressure washer. With the engine (e.g., engine 610)
and the water pump (e.g. water pump 713) off (step 745) and the
pressure washer (e.g., pressure washer 710) not connected to a
fluid supply (e.g., fluid supply 725), there is no water flow
(e.g., substantially no flow) in the fluid system (e.g., supply
hose 723, water pump 713, delivery hose 715, and spray gun 714) and
the water pressure in the fluid system is zero (e.g., substantially
zero). After the pressure washer is connected to the fluid source,
and if necessary, the fluid source is turned on, the fluid source
fills the fluid system and water pressure in the system builds. A
pressure sensor (e.g., pressure sensor 729) detects the water
pressure (e.g., pressure differential, static pressure, dynamic
pressure, fluid pressure, etc.) and provides a signal that
indicates when threshold water pressure is reached (e.g., when the
water pressure is above a threshold pressure or when the pressure
differential meets a threshold differential) (step 750) in the
fluid system (e.g., at or near the line pressure provided by the
fluid supply 725). When a user actuates the trigger, water is
allowed to flow from the spray gun and through the other components
of the fluid system. A flow sensor (e.g., flow sensor 727) detects
the water flow (e.g., flow rate, flow volume) and provides a signal
that indicates threshold water flow is present in the system (e.g.,
when the water flow is above a threshold flow) (step 755). The
threshold flow may be set at a value where that water flow at the
threshold is sufficient to supply the water pump with sufficient
water to run. Steps 750 and 755 can be considered to be in series,
such that threshold pressure in the system must be achieved before
flow in the system is considered. Although illustrated and
described with the pressure sensor checked first and the flow
sensor checked second, the order may be reversed. Alternatively,
steps 750 and 755 can be performed in parallel to each other so
that only one needs to be satisfied to indicate the engine is ready
to start. In some embodiments, only one of the flow sensor and the
pressure sensor is used.
[0090] When the flow sensor indicates threshold flow and the
pressure sensor indicates threshold water pressure, the engine is
ready to be started. In some embodiments, an on delay timer is
provided to ensure that accidental or unintended actuation of the
trigger does not start the engine (step 760). The on delay timer
requires the flow sensor to indicate threshold water flow for a
predetermined amount of time (e.g., 0.5, seconds, 1 second, 1.5
seconds, 3 seconds, 5 seconds, other greater or lesser values)
before the starter motor (e.g., starter motor 120) is turned on to
start the engine. In some embodiments, the on delay timer requires
both the flow sensor to indicate threshold water flow and the
pressure sensor to indicate threshold water pressure for the
predetermined amount of time. Once the predetermined amount of time
is met, the starter motor is turned on (step 765). In other
embodiments, the on delay timer is omitted and the starter motor is
turned on (step 765) as soon as the flow sensor indicates threshold
flow and the pressure sensor indicates threshold pressure. In
embodiments in which pressure sensing is omitted and only flow
sensing is used, the use of the on delay timer helps to ensure that
inadvertent or unintentional actuation of the trigger does not
start the engine.
[0091] The starter motor rotates the crankshaft of the engine to
start the engine. Next, whether the engine is successfully started
is detected (step 770). This can be done in one or more appropriate
ways. For example, a speed sensor (e.g., a governor) can detect
when the engine speed meets a threshold speed indicative of the
engine being started. As another example, ignition pulses can be
used to determine if the engine speed meets the threshold speed.
When a successful engine start is detected, the starter motor is
turned off (step 780).
[0092] In some embodiments, a starter motor cranking timer is
provided to ensure that the starter motor is not running for more
than a predetermined time (e.g., 5 seconds, 10 seconds, other
greater or lesser values) in an unsuccessful attempt to start the
engine (step 775). If the predetermined time elapses before the
engine start is detected, the starter motor cranking timer turns
the starter motor off (step 781). After the starter motor is turned
off, the off delay timer is reset (step 782). Next, the flow sensor
is checked to compare the detected flow to the threshold hold flow
(step 783). Step 783 is dwelled on until the detected flow is below
the threshold flow, at which point the starting sequence can be
reinitialized from step 745. Steps 781-783 ensure that the user
fully releases the trigger, allowing the flow to drop below the
threshold flow, before being able to reinitialized the starting
process. In some embodiments, pressure sensing is used in place of
or in addition to flow sensing. In other embodiments, the starter
motor cranking timer is omitted and the starter motor will run
until the engine start is detected.
[0093] Once the engine is started, the engine will drive the water
pump to provide pressurized water to the spray gun. When the user
releases the trigger of the spray gun with the engine on, the flow
through the system will decrease and stop. When the flow sensor
detects flow below the threshold flow (e.g., a no flow condition)
(step 785), the engine is turned off. In some embodiments, pressure
sensing is used in addition to or in place of flow sensing. For
example, in some embodiments, the engine is turned off in response
to the pressure sensor detecting pressure below a threshold
pressure (e.g., if the pump inlet is disconnected from the fluid
supply). In some embodiments, as illustrated in FIG. 15, an off
delay timer is provided to allow the user to interrupt use of the
spray gun without turning off the engine (step 790). The off delay
timer requires the flow sensor to detect flow below the threshold
water flow (step 785) for a predetermined amount of time (e.g., 5
seconds, 10 seconds, 15 seconds, other greater or lesser values)
before turning off the engine. The predetermined amount of time for
the off delay timer may be set by the user. Once the predetermined
amount of time is met, the engine is turned off (step 745). In some
embodiments, the off delay timer is reset when the flow sensor
detects flow above the threshold water flow while the off delay
timer is running (step 787). In this way, the user can reset the
timer by re-actuating the trigger and restarting fluid flow and
continue to use the pressure washer without having to restart the
engine. In some embodiments, pressure sensing is used in addition
to or in place of flow sensing, with the timer started, stopped,
and reset in response to changes in detected pressure and/or
detected pressure relative to one or more threshold pressures. In
some embodiments, the engine speed is reduced (e.g., by an
automatic throttle system), while the off delay timer is running
(step 791). This reduces noise and fuel consumption while the off
delay timer is running.
[0094] A manual stop (e.g., manual stop button 731) is provided so
that the user may always manually stop the engine (step 795).
[0095] According to an exemplary embodiment, the electrical control
circuits shown in FIGS. 10-11, 13, and 13A and the method shown in
FIG. 15 are contained on or implemented by non-programmable
circuitry, circuit boards, or a processing circuit. The hard-wired
logic, circuitry, and processing circuit are collectively referred
to as a "controller" (e.g., controller 132 shown in FIG. 14). A
processing circuit can include a processor and memory device.
Processor can be implemented as a general purpose processor, an
application specific integrated circuit (ASIC), one or more field
programmable gate arrays (FPGAs), a group of processing components,
or other suitable electronic processing components. Memory device
(e.g., memory, memory unit, storage device, etc.) is one or more
devices (e.g., RAM, ROM, Flash memory, hard disk storage, etc.) for
storing data and/or computer code for completing or facilitating
the various processes, layers and modules described in the present
application. Memory device may be or include volatile memory or
non-volatile memory. Memory device may include database components,
object code components, script components, or any other type of
information structure for supporting the various activities and
information structures described in the present application.
According to an exemplary embodiment, memory device is communicably
connected to processor via processing circuit and includes computer
code for executing (e.g., by processing circuit and/or processor)
one or more processes described herein. In some embodiments, each
circuit or another such circuit is configured to detect when the
bail closes (or opens) a switch (see, e.g., switch 518 as shown in
FIG. 5). In other embodiments, a circuit is configured to sense
when the brake is pulled (see, e.g., brake pad 514 as shown in FIG.
5), and then to enable ignition of the engine. In other
contemplated embodiments, a circuit may be further configured to
sense vibration of the engine or Venturi vacuum strength in the
carburetor, and cut power to the motor when the associated
information indicates that the engine is running.
[0096] According to an exemplary embodiment, the circuits shown in
FIGS. 10-11, 13, and 13A and the method shown in FIG. 15 are
contained on or implemented by non-programmable circuitry, circuit
boards, or a processing circuit (e.g., controller 132) that are
integrated with a component of the engine, and may be fully powered
by the energy storage device 130 or 622 or other on-board source.
The various ways of implementing these controls (e.g., hard-wired
logic, non-programmable circuitry, and processing circuit) are
collectively referred to as a "controller." Accordingly, the
controller may require no electrical interface or connection to
components of the lawn mower or other outdoor power equipment aside
from those carried by or integrated with the engine. No additional
wiring or hook ups are required. Accordingly, the assembly process
for the associated outdoor power equipment may be improved, as
discussed above.
[0097] Alternatively, in accordance with another exemplary
embodiment, the circuits shown in FIGS. 10-11, 13, and 13A and the
method shown in FIG. 15 may be contained on or implemented by
non-programmable circuitry, circuit boards, or a processing circuit
within the housing of the energy storage device (see, e.g., energy
storage device 130 and removable energy storage device 622), and
may be fully powered by the energy storage device (e.g., battery or
other power source). The various ways of implementing these
controls (e.g., hard-wired logic, non-programmable circuitry, and
processing circuit) are collectively referred to as a "controller."
As is known, energy storage devices generally have integrated
circuitry contained therein that is configured to monitor operating
variables of the energy storage device (current, voltage, etc.)
related to its charge state. Thus, the addition of the circuits of
FIGS. 10-11, 13, and 13A or the method of FIG. 15 to the existing
circuit board(s) or on an additional circuit board within the
housing of the energy storage device is possible. The controller
also receives an existing engine speed sensor input. In this way,
the controller may require no electrical interface to components of
the lawn mower or other outdoor power equipment, and no additional
wiring or hook ups are necessary.
[0098] Alternatively, in accordance with another exemplary
embodiment, the circuits shown in FIGS. 10-11, 13, and 13A and the
method shown in FIG. 15 may be contained on or implemented by
non-programmable circuitry, circuit boards, or a processing circuit
within the housing of the receiving port 626 that receives the
removable energy storage device 622. The various ways of
implementing these controls (e.g., hard-wired logic,
non-programmable circuitry, and processing circuit) are
collectively referred to as a "controller." This eliminates the
need to include the circuitry or controller in each removable
energy storage device 622 that may be used with the outdoor power
equipment. Also, this provides original equipment manufacturers
("OEMs") with a modular electric start system where the receiving
port 626 can be incorporated into the final product at location of
the OEM's choosing and not be limited to a location on the engine
610.
[0099] Accordingly, the assembly process for the associated outdoor
power equipment may be simplified and improved. Furthermore, the
circuits of FIGS. 10-11, 13, and 13A and the method of FIG. 15 are
only exemplary, and the specifics of the non-programmable circuitry
may be altered to optimize the integration of their functionality
onto the existing circuit board(s) or additional circuit board(s)
within the energy storage device.
[0100] Referring now to FIG. 16, outdoor power equipment 810 is
illustrated schematically. Outdoor power equipment 810 is similar
to outdoor power equipment 410 described above.
[0101] Outdoor power equipment 810 includes an engine 812 and an
implement 814 (e.g., mower blade, pump, auger, tiller, alternator,
brush, log-splitter, etc.) driven by the engine 812. In some
embodiments, an electric motor 816 (e.g., a starter motor) is
coupled to the engine 812, and the implement 814 is coupled to a
power takeoff 818 of the engine 812. A speed sensor 820 may be
coupled to the engine 812 to detect the speed of the engine 812. A
run sensor 822 is configured to detect when the implement 814 is in
a ready-to-run condition. Depending on the type of outdoor power
equipment 810, the run sensor 822 can take different forms. For
example, the run sensor 822 may be a switch configured to detect
the state (e.g., engaged or disengaged) of a brake or clutch (e.g.,
for a lawn mower), a switch configured to detect operator presence
in the operating position (e.g., a seat switch on a tractor or a
hand-actuated switch or bail on a handle), an enable fob or key
configured to allow the engine 812 to start when actuated or
present and prevent the engine 812 from starting when not actuated
or present, a switch configured to sense water or another fluid
(e.g., a capacitive water detection sensor, a pressure sensor, a
flow sensor) to ensure that a pump has sufficient fluid to operate
safely (e.g., for a pressure washer or waste pump).
[0102] For example, in a lawn mower including a mower blade as the
implement 814, the run sensor 822 detects when a brake that
selectively prevents the blade from rotating is in a released
position so that the blade is allowed to rotate. The mower blade is
in the ready-to-run condition when the brake is released. In
another example, in a pressure washer including a fluid pump as the
implement 814, the run sensor 822 detects a threshold fluid flow
through the fluid pump to a spray gun. The fluid pump is in the
ready-to-run condition when the threshold fluid flow is detected
(e.g., by flow rate, by flow volume, by fluid pressure, etc.) that
is indicative of sufficient fluid supplied to the fluid pump to
allow for operation of the fluid pump. In another example of a
pressure washer including a fluid pump as the implement 814, the
fluid pump is in the ready-to-run condition when the run sensor 822
detects the presence or actuation of an enable key or fob. In some
embodiments, the outdoor power equipment 810 includes more than one
run sensor 822 and all the run sensors 822 must be satisfied before
the implement 814 is considered to be in the ready-to-run
condition.
[0103] A release mechanism 826 (e.g., a bail for a lawn mower, a
spray gun trigger for a pressure washer, a start button or switch,
etc.) is movable to an engaged position to put the implement 814 in
the ready-to-run condition. In a lawn mower example, the release
mechanism 826 can be a bail connected to a handle 824 and the bail
is configured to allow a user to release the brake by moving the
bail to the engaged position. The run sensor 822 detects that the
brake is released, thereby putting the mower blade into the
ready-to-run condition. If the bail is not moved to the engaged
position (e.g., when the bail is blocked by an interlock as
described above), the brake is not released and the mower blade
will not be put in the ready-to-run condition.
[0104] In a pressure washer example, the release mechanism can be
the trigger of a spray gun fluidly connected to a fluid pump. The
trigger is configured to allow fluid to flow through the spray gun
when the trigger is moved to the engaged or open position. The
trigger in the open position allows a threshold fluid flow through
the fluid pump that is indicative of the fluid pump in the
ready-to-run condition. The run sensor 822 detects the threshold
fluid flow. If the threshold fluid flow is not established, the
fluid pump is not in the ready-to-run condition and the
ready-to-run condition is not detected by the run sensor 822. For
example, this may happen if the pressure washer is not connected to
a fluid supply (e.g., a water faucet or outlet), or there is a leak
or loose connection between the pressure washer and a fluid supply.
Alternatively, in some embodiments, the release mechanism 826 can
be a start actuator (e.g., a start push-button or key-switch).
[0105] Outdoor power equipment 810 also includes a battery 828 for
powering the motor 816 and other components of the outdoor power
equipment 810 and an electric start control module 830 for
operating the motor 816. As illustrated in FIG. 16, the control
module 830 is spaced apart from (separate from, distinct from) the
engine 812. The control module 830 is configured to receive inputs
associated with the release mechanism 826 and the run sensor 822.
In some embodiments, when the release mechanism 826 is moved to the
engaged position, the release mechanism 826 actuates a switch 832,
which provides a signal to the control module 830. The signal may
be provided via a mechanical linkage, wirelessly, a hardwired
electrical connection, or otherwise. The control module 830 checks
the run sensor 822 to determine if the implement 814 is in the
ready-to-run condition. When both the switch 832 and the run sensor
822 provide signals or inputs indicating the implement 814 is in
the ready-to-run condition, the control module 830 then actuates
the motor 816 to start the engine 812. Additional information or
control logic may also be configured to start the engine in
combination with the status of the switch 832, the run sensor 822
and/or other factors. Movement of the release mechanism 826 to the
engaged position can simultaneously provide a start signal to the
control module 830 via the switch 832 as well as put the implement
814 in the ready-to-run condition as detected by the run sensor
822, such that no additional user operations are required to start
the engine 812.
[0106] According to an exemplary embodiment, the control module 830
is configured to receive additional inputs from the speed sensor
820. The speed sensor 820 provides the control module 830 with
information associated with the speed of the engine 812. In some
embodiments, the speed sensor 820 is configured to detect when the
engine 812 is running at a threshold speed. When the engine 812 is
running at the threshold speed, the control module 830 then turns
off the motor 816 (e.g., disengages, disconnects, cuts power to,
etc.). In some embodiments, the speed sensor 820 is a component of
or otherwise coupled to an ignition coil of the engine to detect
the engine speed. In other embodiments, the speed sensor 820 is a
component of or otherwise coupled to a governor to detect the
engine speed.
[0107] In contemplated embodiments, the control module 830
associated with the start system may receive additional or
different inputs used to control starting of the engine, such input
from a sensor configured to indicate whether the outdoor power
equipment has moved recently. Movement of an axle or wheels of such
outdoor power equipment may trigger a sensor that provides a signal
to the control module. The signal, in combination with an electric
timer providing time-related context for the movement, may serve as
an additional indicator that the operator intends to activate the
engine. In contemplated embodiments, the control module 830
includes a timer and is configured to deactivate the motor if the
engine has not started within a predetermined amount of time. In
some contemplated embodiments, the control module 830 includes a
temperature sensor and is configured to prime the engine with an
automated primer pump or adjust the choke or throttle plate if
ambient temperature is above or below a predetermined temperature,
if a portion of the engine is above or below a predetermined
temperature, or if the difference between ambient and engine
temperature is above or below a predetermined value. In
contemplated embodiments, the control module 830 may also provide a
signal output to the operator, such as a visible indicator on a
display coupled to the handle or engine, or an audible alert. In
some such embodiments, the signal output may include as an error
message, a low-fuel message, a replace-oil message, or another such
message.
[0108] Referring now to FIG. 17, the control module 830 is
illustrated according to an exemplary embodiment. The control
module 830 includes a housing 834, a controller 836 configured to
implement control logic for operation of the outdoor power
equipment 810, a connector 838 configured to be electrically
coupled to a release assembly wiring harness 840, and a connector
842 configured to be electrically coupled to the electric motor
816. The connectors 838 and 842 are located on opposite sides of
the housing 834 to accommodate connecting the control module 830
inline with one or more wiring harnesses. The controller 836 is
positioned within the housing 834. In some embodiments, the control
module 830 includes a connector 844 configured to be electrically
coupled to the speed sensor 820. The connector 844 is located on an
opposite side of the housing 834 from one of the connectors 838 and
842. In some embodiments, the switch 832 is a component of the
control module 830 and is positioned within the housing 834.
[0109] In some embodiments, the control module 830 also includes
one or more connectors 846 and 848 configured to be electrically
coupled to a run sensor 822 to provide inputs from the run sensor
822 to the controller 836. The run sensors 822 are considered to be
connected in parallel to the control module 830. Alternatively,
more than one run sensor 822 can be connected to a single connector
846 so that the controller 836 receives a single run sensor input,
but only when all of the run sensors 822 are satisfied that the
implement 814 is in the ready-to-run condition. In such an
embodiment, the run sensors 822 are considered to be connected in
series to the control module 830. In some embodiments, the input
from the run sensor is provided via a wiring harness (e.g., the
release assembly wiring harness 840), electrically coupled to
connectors 838 or 842, so no separate connector for a run sensor is
required to provide a run sensor input to the controller 836. Each
connector 846 and 848 is located on an opposite side of the housing
834 from one of the connectors 838 and 842.
[0110] The controller 836 may include components configured to
implement hard wired control logic or a processing circuit. The
processing circuit can include a processor and memory device. The
processor can be implemented as a general purpose processor, an
application specific integrated circuit (ASIC), one or more field
programmable gate arrays (FPGAs), a group of processing components,
or other suitable electronic processing components. The memory
device (e.g., memory, memory unit, storage device, etc.) is one or
more devices (e.g., RAM, ROM, Flash memory, hard disk storage,
etc.) for storing data and/or computer code for completing or
facilitating the various processes, layers and modules described in
the present application. The memory device may be or include
volatile memory or non-volatile memory. The memory device may
include database components, object code components, script
components, or any other type of information structure for
supporting the various activities and information structures
described in the present application. According to an exemplary
embodiment, the memory device is communicably connected to the
processor via the processing circuit and includes computer code for
executing (e.g., by processing circuit and/or processor) one or
more processes described herein.
[0111] The release assembly wiring harness 840 electrically couples
the electric motor 816, the run sensor 822, and the battery 828
together. For example, in the lawn mower example, the release
assembly wiring harness is the bail wiring harness electrically
connecting the release assembly including the release mechanism or
bail 826 to the electric motor 816 and the motor 816. By connecting
the connector 838 to the release assembly wiring harness 840 (e.g.,
the bail wiring harness of a lawn mower) and connecting the
connector 842 to the electric motor 816, the control module 830 is
electrically coupled to the release assembly wiring harness
840.
[0112] By connecting the control module 830 to existing wiring,
outdoor power equipment configured to be pull started (e.g., by a
recoil starter) is converted to electric start. The control module
830 is easily connected inline with existing wiring, thereby
eliminating the need for adding additional wiring or significantly
rerouting wiring for an electric start outdoor power equipment
model as compared to a pull start outdoor power equipment model.
The control module 830 is relatively small in size and light
weight. This allows the control module 830 to be connected to
existing wiring and not physically mounted to any other component
of the outdoor power equipment. That is, once connected to the
existing wiring, the control module 830 is free to remain otherwise
unsupported (e.g. dangle with the existing wiring harnesses) by a
mount, bracket, or other physical support structure on the outdoor
power equipment. The control module 830 allows a manufacturer to
provide an outdoor power equipment product available as either a
pull start model or an electric start model while simplifying the
manufacturing process. The manufacturing process is simplified
because the control module 830 that converts the outdoor power
equipment to electric start is connected to existing components
(i.e., the release assembly wiring harness 840 and the electric
motor 816) of the pull start outdoor power equipment and does not
require a separate physical mounting structure.
[0113] Alternatively, in accordance with another exemplary
embodiment, the circuits shown in FIGS. 10-11 and 13 and the method
shown in FIG. 15 may be contained on or implemented by an electric
start control module 830 as described above. The hard-wired logic,
circuitry, and processing circuit are collectively referred to as a
"controller."
[0114] The construction and arrangements of the starter system for
an engine, as shown in the various exemplary embodiments, are
illustrative only. Although only a few embodiments have been
described in detail in this disclosure, many modifications are
possible (e.g., variations in sizes, dimensions, structures, shapes
and proportions of the various elements, values of parameters,
mounting arrangements, use of materials, colors, orientations,
etc.) without materially departing from the novel teachings and
advantages of the subject matter described herein. Some elements
shown as integrally formed may be constructed of multiple parts or
elements, the position of elements may be reversed or otherwise
varied, and the nature or number of discrete elements or positions
may be altered or varied. The order or sequence of any process,
logical algorithm, or method steps may be varied or re-sequenced
according to alternative embodiments. Other substitutions,
modifications, changes and omissions may also be made in the
design, operating conditions and arrangement of the various
exemplary embodiments without departing from the scope of the
present invention.
[0115] The present disclosure contemplates methods, systems and
program products on any machine-readable media for accomplishing
various operations. The embodiments of the present disclosure may
be implemented using existing computer processors, or by a special
purpose computer processor for an appropriate system, incorporated
for this or another purpose, or by a hardwired system. Embodiments
within the scope of the present disclosure include program products
comprising machine-readable media for carrying or having
machine-executable instructions or data structures stored thereon.
Such machine-readable media can be any available media that can be
accessed by a general purpose or special purpose computer or other
machine with a processor. By way of example, such machine-readable
media can comprise RAM, ROM, EPROM, EEPROM, CD-ROM or other optical
disk storage, magnetic disk storage or other magnetic storage
devices, or any other medium which can be used to carry or store
desired program code in the form of machine-executable instructions
or data structures and which can be accessed by a general purpose
or special purpose computer or other machine with a processor. When
information is transferred or provided over a network or another
communications connection (either hardwired, wireless, or a
combination of hardwired or wireless) to a machine, the machine
properly views the connection as a machine-readable medium. Thus,
any such connection is properly termed a machine-readable medium.
Combinations of the above are also included within the scope of
machine-readable media. Machine-executable instructions include,
for example, instructions and data which cause a general purpose
computer, special purpose computer, or special purpose processing
machines to perform a certain function or group of functions.
[0116] Although the figures may show or the description may provide
a specific order of method steps, the order of the steps may differ
from what is depicted. Also two or more steps may be performed
concurrently or with partial concurrence. Such variation will
depend on various factors, including software and hardware systems
chosen and on designer choice. All such variations are within the
scope of the disclosure. Likewise, software implementations could
be accomplished with standard programming techniques with rule
based logic and other logic to accomplish the various connection
steps, processing steps, comparison steps and decision steps.
* * * * *