U.S. patent application number 13/804898 was filed with the patent office on 2013-08-08 for cordless mower including cooling air flow arrangement.
This patent application is currently assigned to BLACK & DECKER INC.. The applicant listed for this patent is Black & Decker Inc.. Invention is credited to Joshua D. Eaton, Patrick Marcil, James D. Marshall, Michael A. Milligan, Patrick W. Mooney, Richard P. Rosa, David M. Shaver, Mark Slobodian.
Application Number | 20130199146 13/804898 |
Document ID | / |
Family ID | 45349068 |
Filed Date | 2013-08-08 |
United States Patent
Application |
20130199146 |
Kind Code |
A1 |
Rosa; Richard P. ; et
al. |
August 8, 2013 |
CORDLESS MOWER INCLUDING COOLING AIR FLOW ARRANGEMENT
Abstract
A cordless mower includes a deck, a rechargeable battery, a
blade for cutting grass, a blade motor and a drive motor. The deck
is supported by front and rear wheels and has a top side, a bottom
side, a front end and a rear end. The rechargeable battery is
supported on the deck. The blade is on the bottom side of the deck
and is coupled with a blade motor. The drive motor is connected to
the rear wheels for driving said rear wheels to move the mower. The
drive motor is located in a chamber at the rear of the mower
adjacent the rear wheels. The chamber has an opening therein to
allow air to flow through.
Inventors: |
Rosa; Richard P.; (Kingston,
CA) ; Shaver; David M.; (Brockville, CA) ;
Marcil; Patrick; (Ottawa, CA) ; Eaton; Joshua D.;
(Athens, CA) ; Slobodian; Mark; (Ottawa, CA)
; Marshall; James D.; (Gananoque, CA) ; Milligan;
Michael A.; (Gananoque, CA) ; Mooney; Patrick W.;
(Brockville, CA) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Black & Decker Inc.; |
Newark |
DE |
US |
|
|
Assignee: |
BLACK & DECKER INC.
Newark
DE
|
Family ID: |
45349068 |
Appl. No.: |
13/804898 |
Filed: |
March 14, 2013 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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12975499 |
Dec 22, 2010 |
8429885 |
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13804898 |
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12838898 |
Jul 19, 2010 |
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12975499 |
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29361418 |
May 11, 2010 |
D642119 |
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12838898 |
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12426499 |
Apr 20, 2009 |
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29361418 |
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61048002 |
Apr 25, 2008 |
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Current U.S.
Class: |
56/10.2R ;
56/10.5; 56/10.7; 56/16.7 |
Current CPC
Class: |
B60L 3/0023 20130101;
Y02E 60/10 20130101; B60L 2240/12 20130101; B60L 2240/36 20130101;
B60L 50/52 20190201; A01D 69/02 20130101; Y02T 10/7072 20130101;
B60L 3/0061 20130101; B60L 53/80 20190201; A01D 34/81 20130101;
Y02T 90/14 20130101; B60L 1/003 20130101; Y02T 90/12 20130101; Y02T
10/70 20130101; A01D 34/006 20130101; B60L 50/66 20190201; A01D
34/78 20130101; B60L 58/21 20190201; A01D 42/005 20130101; B60L
2250/24 20130101; H01M 2/1072 20130101; A01D 34/69 20130101; B60L
2200/40 20130101; A01D 34/824 20130101 |
Class at
Publication: |
56/10.2R ;
56/10.7; 56/10.5; 56/16.7 |
International
Class: |
A01D 34/69 20060101
A01D034/69; A01D 34/78 20060101 A01D034/78; A01D 34/00 20060101
A01D034/00 |
Claims
1.-5. (canceled)
6. A cordless mower comprising: a deck supported by front and rear
wheels, the deck having a top side, a bottom side, a front end and
a rear end; a rechargeable battery supported on said deck; a drive
motor connected to the rear wheels for driving said rear wheels to
move the mower; a speed lever controlled by a user to set the speed
of the mower; and a control circuit connected to the speed lever
that controls the amount of current delivered from the battery to
the drive motor, the control circuit monitoring the drive motor and
shutting off the drive motor when the current being delivered
exceeds a first predetermined current for a first predetermined
period of time.
7. The cordless mower of claim 6, wherein the control circuit shuts
off the drive motor when the current being delivered exceeds a
second predetermined current for a second predetermined time
period, wherein the second predetermined current is higher than the
first predetermined current, and the second predetermined time
period is shorter than the first predetermined time period.
8. The cordless mower of claim 6 wherein the drive motor is
connected to the rear wheels through at least one gear mechanism,
the drive motor having an rpm of 6,000 to 17,000 rpm and the gear
mechanism having a gear reduction between 90:1 and 130:1.
9. The cordless mower of claim 8, wherein the gear mechanism has
three separate gear reductions, and at least one is a planetary
gear reduction and another a worm gear reduction.
10. The cordless mower of claim 6, further including a blade motor
mounted generally centrally on the deck, the blade motor and drive
motor being powered by the rechargeable battery, the blade motor
having independent controls from the drive motor.
11. A cordless mower comprising: a deck supported by front and rear
wheels, the deck having a top side, a bottom side, a front end and
a rear end; a rechargeable battery supported on said deck; a drive
motor connected to the rear wheels for driving said rear wheels to
move the mower; a blade motor coupled to a blade; a handle secured
to said the rear end of said deck, and said handle having a blade
bail for controlling power to the blade motor and a drive bail for
controlling power to said drive motor so that power to the blade
motor and the drive motor are independently controlled.
12. The cordless mower of claim 11, further comprising a control
circuit monitoring the drive motor and shutting off the drive motor
when the current being delivered exceeds a first predetermined
current for a first predetermined period of time.
13. The cordless mower of claim 12, wherein the control circuit
shuts off the drive motor when the current being delivered exceeds
a second predetermined current for a second predetermined time
period, wherein the second predetermined current is higher than the
first predetermined current, and the second predetermined time
period is shorter than the first predetermined time period.
14. The cordless mower of claim 11, further comprising a safety key
that is electrically coupled to both the blade motor and drive
motor, so that when present, electrical power may be delivered from
the battery to both the blade motor and drive motor, and when
absent, no power can be delivered to the blade motor and drive
motor.
15. The cordless mower of claim 11 wherein the drive motor is
connected to the rear wheels through at least one gear mechanism,
the drive motor having an rpm of 6,000 to 17,000 rpm and the gear
mechanism having a gear reduction between 90:1 and 130:1.
16. A cordless mower comprising: a deck supported by front and rear
wheels, the deck having a top side, a bottom side, a front end and
a rear end, the bottom side defining a cutting chamber and a
discharge passage extending rearwardly from the cutting chamber to
the rear of said mower; a rechargeable battery supported on said
deck; a blade for cutting grass arranged within the cutting
chamber; and a mulch door positioned in said discharge passage and
movable between an open and closed position, the mulch door
rotating about a vertical shaft that is connected to a user
controlled knob located at a top side of the deck.
17. The cordless mower of claim 16 wherein the discharge passage
defines a grass outlet aperture at the rear end of the deck and the
mulch door is positioned inwardly of the grass outlet aperture and
wherein the mulch door swings outwardly when moving from the closed
to open position so that any debris in the discharge passage behind
the mulch door is swept into the grass outlet aperture and removed
from the discharge passage.
18. The cordless mower of claim 16 further including a rear
discharge door spaced from the rear end of the deck to create a
discharge cavity to direct debris downward.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application is a division of U.S. Ser. No. 12/975,499
filed Dec. 22, 2010, which is a continuation-in-part of U.S. Ser.
No. 12/838,898 filed Jul. 19, 2010, which is a continuation-in-part
of U.S. Design Application No. 29/361,418 filed on May 11, 2010,
(now U.S. Pat. No. D642,119 issued on Jul. 26, 2011) and a
continuation-in-part of U.S. application Ser. No. 12/426,499 filed
Apr. 20, 2009, which claims the benefit and priority of U.S.
Provisional Application No. 61/048,002 filed Apr. 25, 2008. The
entire disclosure of each of the above applications is incorporated
herein by reference.
FIELD
[0002] The present disclosure relates to lawn mowers and more
specifically to a cordless electric lawn mower.
BACKGROUND
[0003] Due to concerns regarding urban air pollution, the problems
and maintenance needs of gas engines, as well as other factors,
electric lawn mowers are gaining in popularity. Moreover, due to
the inconveniences and operating limitations of corded electric
mowers, battery operated cordless electric mowers may be preferred.
As described herein however, such battery operated mowers can have
drawbacks.
[0004] Some of these drawbacks can be associated with the
functionality of the battery, including battery life and the
storage and transfer of the battery, including insertion and
removal of the battery from the mower.
[0005] Other drawbacks are associated with self-drive transmissions
that use a belt-tensioning drive system, whereby the tension on a
set of variable stepped sheaves can be configured to control the
speed of a drive axle from a continuous speed motor. Such a system
however is inefficient because the self-drive motor must run
constantly at high speed, thereby constantly drawing maximum power.
Furthermore, as is known in the art, efficiency losses are observed
in such a slipping belt system.
[0006] According to other drawbacks associated with battery
operated mowers, in some instances during high-load grass cutting
(i.e., wet, and/or thick grass), the operating speed of the blade
motor(s) is reduced while the speed of a self-drive motor is
unchanged. In this way, cutting performance is degraded because the
speed of the self-drive motor is not adjusted to compensate for the
reduced operating speed of the blade motor.
[0007] Other drawbacks associated with battery operated mowers
involve a cumbersome mulching mode switching process and inadequate
driver feedback information. For example, it may be desirable for
an operator to easily obtain information relating to battery-power,
mower blade operation, self-drive motor operation and/or other
information, such as operational faults associated with the
mower.
SUMMARY
[0008] A cordless mower includes a deck, a rechargeable battery, a
blade for cutting grass, a blade motor and a drive motor. The deck
is supported by front and rear wheels and has a top side, a bottom
side, a front end and a rear end. The rechargeable battery is
supported on the deck. The blade is on the bottom side of the deck
and is coupled with a blade motor. The drive motor is connected to
the rear wheels for driving said rear wheels to move the mower and
is located in a chamber at the rear of the mower adjacent the rear
wheels. The chamber has an opening therein to allow air to flow
through.
[0009] A cordless mower includes a deck, a rechargeable battery, a
drive motor, a speed lever and a control circuit. The deck is
supported by front and rear wheels and has a top side, a bottom
side, a front end and a rear end. The rechargeable battery is
supported on said deck. The drive motor is connected to the rear
wheels for driving said rear wheels to move the mower. The speed
lever is controlled by a user to set the speed of the mower. The
control circuit is connected to the speed lever and controls the
amount of current delivered from the battery to the drive motor.
The control circuit monitors the drive motor and shuts off the
drive motor when the current being delivered exceeds a
predetermined current for a predetermined period of time.
[0010] A cordless mower includes a deck, a rechargeable battery, a
drive motor, a blade motor and a handle. The deck is supported by
front and rear wheels and has a top side, a bottom side, a front
end and a rear end. The rechargeable battery is supported on said
deck. The drive motor is connected to the rear wheels for driving
said rear wheels to move the mower. The blade motor is coupled to a
blade. The handle is secured to the rear end of said deck. The
handle has a blade bail for controlling power to the blade motor
and a drive bail for controlling power to said drive motor so that
power to the blade motor and the drive motor are independently
controlled.
[0011] A cordless mower includes a deck, a rechargeable battery, a
blade for cutting grass and a mulch door. The deck is supported by
front and rear wheels and has a top side, a bottom side, a front
end and a rear end. The bottom side defines a cutting chamber and a
discharge passage extending rearwardly from the cutting chamber to
the rear of said mower. The rechargeable battery is supported on
said deck. The blade is arranged within the cutting chamber. The
mulch door is positioned in said discharge passage and is movable
between an open and closed position. The mulch door rotates about a
vertical shaft that is connected to a knob located at a top side of
the deck.
[0012] Further areas of applicability will become apparent from the
description provided herein. It should be understood that the
description and specific examples are intended for purposes of
illustration only and are not intended to limit the scope of the
present disclosure.
DRAWINGS
[0013] The drawings described herein are for illustration purposes
only and are not intended to limit the scope of the present
disclosure in any way.
[0014] FIG. 1 is a schematic block diagram of an exemplary
battery-powered mower constructed in accordance with the teachings
of the present disclosure;
[0015] FIG. 2 is a perspective view of an exemplary battery-powered
lawn mower constructed in accordance with the teachings of the
present disclosure;
[0016] FIG. 3 is a partial perspective view of the exemplary
battery-powered lawn mower shown in FIG. 2 in a first
configuration;
[0017] FIG. 4 is a partial perspective view of the exemplary
battery-powered lawn mower shown in FIG. 2;
[0018] FIG. 5 is a partial perspective view of the exemplary
battery-powered lawn mower shown in FIG. 2 in a second
configuration;
[0019] FIG. 6 is a perspective view of the exemplary
battery-powered lawn mower shown in FIG. 2 with the battery being
removed from the pocket;
[0020] FIG. 7 is a partial plan view of the exemplary
battery-powered lawn mower shown in FIG. 2 with the battery removed
to illustrate the pocket;
[0021] FIG. 8 is a perspective view of the battery of the exemplary
battery-powered lawn mower shown in FIG. 2;
[0022] FIG. 9 is another perspective view of the battery of the
exemplary battery-powered lawn mower shown in FIG. 2;
[0023] FIG. 10 is a bottom view of the battery of the exemplary
battery-powered lawn mower shown in FIG. 2;
[0024] FIG. 11 is a partial perspective view of the battery of the
exemplary battery-powered lawn mower shown in FIG. 2 with a portion
of the battery housing removed to illustrate a series of cells
housed therein;
[0025] FIG. 12 is a partial perspective view of a control of the
exemplary battery-powered lawn mower shown in FIG. 2;
[0026] FIG. 13 is a perspective view of a safety key corresponding
to the exemplary battery-powered lawn mower shown in FIG. 2;
[0027] FIG. 14 is a partial sectional view of the safety key of
FIG. 13;
[0028] FIG. 15 is a partial perspective view of the battery of the
exemplary battery-powered lawn mower shown in FIG. 2 with an
exemplary charger cable;
[0029] FIG. 16 is a partial perspective view of the exemplary
control assembly shown in FIG. 12 with an exemplary charger
cable;
[0030] FIG. 17 is another partial perspective view of a control
assembly of the exemplary battery-powered lawn mower shown in FIG.
2;
[0031] FIG. 18 is a partial plan view of the exemplary
battery-powered lawn mower shown in FIG. 2 in a mulch
configuration;
[0032] FIG. 19 is a partial plan views of the exemplary
battery-powered lawn mower shown in FIG. 2 in a discharge
configuration;
[0033] FIG. 20 is a partial perspective view of a drive mechanism
of the exemplary battery-powered lawn mower shown in FIG. 2;
[0034] FIG. 21 is a partial perspective rear view of the exemplary
battery-powered lawn mower shown in FIG. 2 showing a mulch
door;
[0035] FIG. 22 is another partial perspective rear view of the
exemplary battery-powered lawn mower shown in FIG. 2 showing a
mulch door;
[0036] FIG. 23 is another partial perspective view of the exemplary
battery-powered lawn mower shown in FIG. 2;
[0037] FIG. 24 is a partial perspective view of a mulch door
rotation mechanism of the exemplary battery-powered lawn mower
shown in FIG. 2;
[0038] FIG. 25 is a partial perspective view of a mulch door
rotation mechanism of the exemplary battery-powered lawn mower
shown in FIG. 2;
[0039] FIG. 26 is another partial perspective rear view of the
exemplary battery-powered lawn mower shown in FIG. 2;
[0040] FIG. 27 is another partial perspective rear view of the
exemplary battery-powered lawn mower shown in FIG. 2;
[0041] FIG. 28 is a partial perspective view of the exemplary
battery-powered lawn mower shown in FIG. 2 with a portion of the
deck removed;
[0042] FIG. 29 is a partial sectional view taken through the deck
of the exemplary battery-powered lawn mower shown in FIG. 2;
[0043] FIG. 30 is a partial perspective view of a knob assembly of
the exemplary battery-powered lawn mower shown in FIG. 2; and
[0044] FIG. 31 is a side view of the exemplary battery-powered lawn
mower shown in FIG. 2 in a storage configuration.
DETAILED DESCRIPTION
[0045] With initial reference to FIG. 1, an exemplary
battery-powered lawn mower 10 (hereinafter, mower) is schematically
illustrated. The mower 10 includes a battery 12, a cutting
mechanism 14 for driving blade(s) 16, a drive mechanism 18 for
driving wheels 30, a control circuit 20 and a user interface 22.
The battery 12 supplies power to the cutting mechanism 14 and the
drive mechanism 18, which in the exemplary embodiment shown is a
blade motor 54 and a drive motor 56, respectively. The amount of
power delivered to the drive mechanism 18 by the battery 12 is
determined by the control circuit 20 which is managed by the user
interface 22.
[0046] With reference to FIGS. 2 and 28, the exemplary
battery-powered lawn mower 10 will be described. The mower 10
includes a deck 50 that provides a mounting structure for various
components of the mower 10, including the blade motor 54 and the
drive motor 56, and generally forms the housing for the blade(s) 16
coupled to the blade motor 54. A shroud 13 is placed over the deck
50 to protect the internal components of the mower 10.
[0047] With reference to FIGS. 6 and 7, the shroud 13 defines a
pocket 51 that receives the battery 12. The battery 12 has a shape
that corresponds to the shape of the pocket 51 such that the
battery 12 fits snugly within the pocket 51.
[0048] With additional reference to FIG. 7, the pocket 51 includes
a base portion 719 with a plurality of walls 715 arranged
substantially perpendicular to the base portion 719. The shape of
the battery 12 complements the shape of the pocket 51 such that the
battery 12 can be inserted within the pocket in a single
orientation. Pocket 51 can define one or more recesses 712A-D (FIG.
7) that correspond to one or more projections 752A-D (FIGS. 9-10)
on the battery 12 and one or more projections 714A-C that
correspond to one or more recesses 754A-C defined by the battery
12. In this manner, the battery 12 can be inserted within the
pocket 51 only when the projection(s) 752A-D, 714A-C and recess(es)
754A-C, 712A-D are properly aligned. Furthermore, the projection(s)
752A-D, 714A-C and recess(es) 754A-C, 712A-D can assist with
guiding the battery 12 to the proper positioning within the pocket
51. Additionally, the walls 715 of pocket 51 can be tapered to
assist in guiding the battery 12 to the proper positioning within
the pocket 51.
[0049] The location of the battery 12 is such that the mower 10 is
well-balanced and stable. The battery 12 (and pocket 51) is
positioned rearward of the longitudinal center 702 of the deck 50
such that a user may more easily maneuver the mower 10. This
position puts more weight towards the rear of the mower, which
provides increased traction to the rear drive wheel(s) 30 and also
aids in tilting or lifting the front wheels off the ground for
better maneuverability. In addition, the battery 12 and pocket 51
may be positioned in the approximate center of the width of the
deck 50 to increase stability and inhibit sideways tipping.
[0050] The blade motor 54 (and the axis of rotation of the blade
16) is arranged along the longitudinal center 702 of the deck 50
(FIGS. 18 and 19). The center 706 of the battery 12/pocket 51 can
be positioned rearward of the longitudinal center 702 by at least
fifty percent of the distance L1 between the longitudinal center
702 and the rear wheel axle axis 708. In other words, the distance
L1 between the longitudinal center 702 and the rear wheel axle axis
708 is at least twice the distance L2 between the center 706 of the
battery 12/pocket 51. For example only, the distance L1 can be 380
millimeters and the distance L2 can be 160 millimeters such that
the distance L1 is 2.375 times the distance L2.
[0051] In order to further increase stability and inhibit tipping
of the mower 10, the depth of the pocket 51 can be increased.
Increasing the depth of the pocket 51 reduces the overall height of
the mower 10 with the battery 12 installed. Further, the battery 12
can comprise a large portion of the overall weight of the mower 10.
Thus, increasing the depth of the pocket 51 also lowers the center
of gravity of the mower 10.
[0052] With reference to FIGS. 3-6, a latch assembly 720 is coupled
to the shroud 13. While latch assembly 720 is an over-center type
latch, other latching configurations are may be substituted
therefore, such as sliding latches or rotating latches. The latch
assembly 720 includes a latch 722 and lever 724. The latch 722
engages a latch catch 755 formed on the battery 12 to secure the
battery 12 within the pocket 51 in a first configuration, as shown
in FIG. 3. The lever 724 is rotated, as shown in FIG. 4, to
disengage the latch 724 from the latch catch 755. In a second
configuration shown in FIG. 5, the latch 722 is fully opened and
completely disengaged from the battery 12 such that the battery 12
can be freely removed from the pocket 51. As more fully described
below, the battery 12 can be removed from the pocket 51 by moving
the battery 12 in the direction of the arrow shown in FIG. 6.
[0053] The latching assembly 720 may further include a biasing
member, e.g., a spring that biases the latching assembly 720 to be
in the second configuration. Upon releasing the latch 722 from
engagement with the latch catch 755, the biasing member may
automatically move the latch 722 to the fully opened position shown
in FIG. 5. In this manner, the latching assembly 720 may be easily
moved from the first configuration (FIG. 3) to the second
configuration (FIG. 5) by a user utilizing one hand. In order to
secure the battery 12 within the pocket 51, a user manually engages
the latch 722 with the latch catch 755 while rotating the lever
724. Then, the lever 724 is moved to the lock position while the
latch 722 is engaged with the latch catch 755 (FIG. 3).
[0054] With reference to FIGS. 2, 7 and 10, in order to
electrically couple the battery 12 with the other components of the
mower 10, a mower connector 716 is provided within the pocket 51.
The mower connector 716 can include one or more projections 717
extending from the pocket 51. The one or more projections 717 are
configured to mate with corresponding recess(es) 757 of a first
battery connector 756 in a male-female connector configuration. The
projection(s) 717 and recess(es) 757 may act as guide features that
assist in positioning the battery 12 within the pocket 51. The
mower connector 716 and/or the first battery connector 756 can be
self-aligning to ensure a proper connection between the mower 10
and battery 12. In some embodiments, the latching assembly 720 is
used to fully secure and couple the mower connector 716 with the
first battery connector 756. The battery 12 may include a second
battery connector 758 (FIGS. 8 and 15), e.g., for connection with a
charger cable 780 (FIG. 15). The second battery connector 758 (FIG.
8) is located on a portion of the battery 12 that is inaccessible
to a user when the battery 12 is in the first configuration, i.e.,
secured within pocket 51, such that the battery 12 cannot be
charged through the second battery connector 758 when the mower 10
is operating. In this way, the first battery connector 756 is
utilized to provide power to the mower 10 and also to charge the
battery 12, while the second battery connector 758 is used only to
charge the battery 12 (via charger cable 780). With reference to
FIG. 15, the charger cable 780 can be constructed to engage with
the second battery connector 758 in a single orientation. Any or
all of the mower connector 716, first battery connector 756 and
second battery connector 758 can be one or more Anderson-type
electrical connectors to ensure proper electrical connections.
[0055] While the battery 12 is secured within pocket 51, the
charger cable 780 is connected to an electrical connector portion
732 associated with user interface 22, as is described more fully
below. User interface 22 is electrically coupled to the mower
connector 716 such that power may be provided to the battery 12
when coupled with mower connector 716.
[0056] A portion of an exemplary user interface 22 is shown in
FIGS. 12 and 16. User interface 22 includes an electrical connector
portion 732 that has three electrical connectors 734A-C. Electrical
connectors 734A-C can be any type of electrical connector, such as
Anderson-type electrical connectors. Electrical connectors 734A and
734B are utilized to connect with charger cable 780 to charge the
mower 10. Electrical connectors 734A and 734C are utilized to
connect with a safety key 740 (FIGS. 13-14), further described
below. In order to inhibit improper connections, the electrical
connectors 734A-C can be arranged such that the charger cable 780
can be engaged with electrical connector portion 732 in a single
orientation, i.e., connected with electrical connectors 734A and
734B.
[0057] In FIGS. 13 and 14, safety key 740 includes two electrical
connectors 742A and 742B. Electrical connectors 742A and 742B are
configured to mate with electrical connectors 734A and 734C of the
user interface 22. For example only, electrical connectors 742A and
742B may be coupled by a jumper 744 to electrically couple
electrical connectors 734A and 734C when the safety key 740 is
mated with electrical connector portion 732. Safety key 740
includes a keyed portion 746 that has a shape that corresponds and
complements the shaped of keyed portion 736 of user interface 22.
The keyed portions 736, 746 and electrical connectors 742A, 742B,
734A and 734C may be constructed and arranged symmetrically such
that the safety key 740 can properly mate with electrical connector
portion 734 in either of two orientations, i.e., 742A with 734A and
742B with 734C or 742A with 734C and 742B with 734A. The safety key
740 operates to connect the battery 12 with the blade and drive
motors 54, 56 when mated with the electrical connector portion 732.
When the safety key is removed from the electrical connector
portion 732, electrical connectors 734A and 734C are decoupled and
power from the battery 12 cannot be delivered to either the blade
and/or drive motors 54, 56.
[0058] An exemplary battery 12 will be described with particular
reference to FIGS. 8-11. Battery 12 includes three cells 770A-C,
which can be connected in series and arranged within a housing 760.
However, it should be understood that the battery may include any
number of cells and fall within the scope of the present
disclosure. The housing 760 includes a first portion 762 mated with
a second portion 764. The first battery connector 756 is arranged
on the second portion 764 and the second battery connector 758 is
arranged on the first portion 762.
[0059] The battery 12 further includes a first handle 766A and a
second handle 766B. The first and second handles 766A-B may be
utilized by a user to insert or remove the battery 12 from the
pocket 51. In a non-limiting example, the first and second handles
766A-B are monolithically formed with the first portion 762 of the
housing 760. The first handle 766A is arranged on a first side 767
of the housing 760 and the second handle 766B is arranged on a
second side 769 of the housing 760 that is opposite the first side
to encourage a user to use two hands when handling the battery
12.
[0060] With reference to FIGS. 7, 8 and 10, the battery 12 is
inserted within pocket 51 as follows. A user positions the battery
12 within pocket 51. For example only, the user may grasp first and
second handles 766A-B in order to lift and position the battery 12
within pocket 51. The battery 12 is properly positioned and fully
inserted within pocket 51 such that the first battery connector 756
engages and mates with mower connector 716. As described above,
various features of the battery 12 and/or pocket 51 assist in the
proper positioning and insertion of the battery 12 (projections
752A-D, 714A-C, 717, recess(es) 754A-C, 712A-D, 757, etc.).
[0061] Once the battery 12 is fully inserted within pocket 51 and
the first battery connector 756 is engaged and mated with mower
connector 716, the user engages the latch 722 with the battery 12,
for example, latch catch 755. The user then rotates the lever 724
to lock the latch 722 and fully secure the battery 12 within the
pocket 51.
[0062] The battery 12 is removed from being fully secured within
pocket 51 as follows. A user rotates lever 724 to unlock the latch
722 from engagement with the battery 12. In some embodiments, the
latch 722 automatically disengages from the battery 12 upon being
unlocked. Alternatively, the user manually disengages the latch 722
from battery 12. A user then grasps the battery (such as, first and
second handles 766A-B) in order to remove the battery 12 from
pocket 51. In various embodiments, the mower connector 716
automatically disengages from first battery connector 756 as the
battery 12 is removed from pocket 51.
[0063] Another view of the user interface 22 is shown in FIG. 17.
User interface 22 is secured to a handle assembly 100. The handle
assembly 100 can include handle frames 103 that generally extend at
an angle from the mower deck 50 to a handle grip 105. The handle
assembly 100 can include a first or blade bail 101 and a second or
drive bail 102. The blade bail 101 can cooperate with a control
cable 104A to selectively provide power from battery 12 to blade
motor 54 to drive blade 16. The drive bail 102 can cooperate with
control cable 104B to communicate with the drive motor 56. In one
example, the blade bail 101 can be rotated toward the handle grip
105 about an axis 101A. The drive bail 102 can be rotated toward
the handle grip 105 about an axis 102A.
[0064] Blade bail 101 is actuated to switch the mower 10 between a
cutting OFF mode and a cutting ON mode. In the cutting OFF mode,
the blade bail 101 electrically disconnects the battery 12 from the
blade motor 54 such that the blade 16 is not driven. In the cutting
ON mode, the blade bail 101 electrically connects the battery 12 to
the blade motor 54 such that the blade 16 may be driven. Similarly,
drive bail 102 is actuated to switch the mower 10 between a
self-drive OFF mode and a self-drive ON mode. In the self-drive OFF
mode, the drive bail 102 electrically disconnects the battery 12
from the drive motor 56 such that the mower 10 is not propelled. In
the self-drive ON mode, the drive bail 102 electrically connects
the battery 12 to the drive motor 56 such that the mower 10 is
propelled, e.g., by drive wheel(s) 30.
[0065] In order to inhibit unintended starting of the blade 16,
user interface 22 can further include a safety lock-out mechanism
107, which prevents coupling the battery 12 with the blade motor
54. Therefore, in order to actuate the blade motor 54, a user
depresses the lock-out mechanism 107 and pulls the blade bail 101
toward the handle grip 105 (that is, rotates the mower blade bail
handle 101 counterclockwise in FIG. 17) to start the blade motor
54. In this manner, a user must complete two independent steps to
actuate the blade bail 101 and start rotation of blade 16. An
example lock-out mechanism 107 is disclosed in U.S. Pat. No.
7,762,049, which is herein incorporated by reference in its
entirety.
[0066] To start the drive mechanism 18 a user urges the drive bail
102 toward the handle grip 105 (that is, rotates the drive bail 102
clockwise in FIG. 17). The drive speed of mower 10 can be adjusted
by moving a speed control lever 108 on the user interface 22. The
speed control lever 108 is coupled to the control circuit 20 which
controls the power delivery from the battery 12 to the drive motor
56. Adjustment of the speed control lever 108 varies the voltage
provided to drive motor 56 and thereby varies the speed of the
mower 10. Alternatively, the drive speed of the mower 10 could be
adjusted based on the position of the drive bail 102 such that, as
the drive bail 102 is rotated clockwise, it progressively makes the
drive mechanism 18 (and the lawn mower 10 as a whole) go faster.
The voltage may be varied, for example, by changing the duty cycle
of a pulse width modulated voltage signal or by adjusting the
magnitude of the voltage delivered to the drive mechanism 18.
[0067] With reference to FIGS. 18-25, the bottom of deck 50 defines
a cutting chamber 120 in which blade 16 is arranged. Cutting
chamber 120 can have a toroidal shape. The deck 50, in combination
with a discharge plate 121, defines discharge passage 122.
Discharge passage 122 extends from the cutting chamber 120 to a
discharge port 123. During operation of mower 10, the discharge
passage 122 provides an outlet for grass and/or other waste to exit
the cutting chamber 120, e.g., to be discharged or collected by a
collection bag 80. A mulch door 124 can be coupled to the deck 50
and be arranged between the cutting chamber 120 and discharge
passage 122. Mulch door 124 can be shaped to complement the
toroidal shape of the cutting chamber 120. The mulch door 124 is
movable between a discharge position (FIG. 19) and a mulch position
(FIG. 18). In the discharge position, the mulch door 124 unblocks
discharge passageway 122 to open the cutting chamber 120 to the
discharge port 123. For example, mulch door 124 can be arranged to
be tangent to the discharge passage 122 in the discharge
configuration (as shown in FIG. 19 in which discharge plate 121 is
not shown). In the mulch position, mulch door 124 blocks discharge
passageway 122.
[0068] The mulch door 124 can be rotated between the discharge and
mulch positions. Referring to FIGS. 23-25, a mulch door rotation
mechanism 130 can be coupled with the mulch door 124 to rotate the
mulch door 124 between the discharge and mulch positions. The mulch
door rotation mechanism 130 can include a knob 131 that is coupled
to the mulch door 124 such that the mulch door 124 rotates with the
knob 131. As shown in the example illustrated in FIGS. 24-25, the
knob 131 is coupled to the mulch door 124 by a vertical shaft 133
that extends through a spacer 134. The spacer 134 is coupled to the
deck 50 and is configured to support the knob 131 in the proper
position in relation to deck 50.
[0069] Discharge plate 121 and deck 50 cooperate to define a grass
outlet aperture 125 in discharge passage 122 (FIG. 22). The grass
outlet aperture 125 provides an outlet for grass clippings and
other waste to exit discharge passage 122. For example, during
rotation of mulch door 124 from the mulch position (FIG. 20) to the
discharge position (FIG. 19) the mulch door 124 will sweep any
grass clippings/waste from the discharge passage 122/discharge
plate 121 out of the grass outlet aperture 125.
[0070] The mulch door rotation mechanism 130 can further include a
locking mechanism 132 that secures the knob 131 and mulch door 124
in specific positions, such as the discharge configuration and the
mulch configuration. In the illustrated example, the locking
mechanism 132 includes a compression spring 135, a pin 136 and one
or more detents defined by the spacer 134, such as first and second
detents 137A, 137B. The pin 136 is fixedly coupled to and rotatable
with knob 131 and is arranged within an aperture 138 defined by
spacer 134. The pin 136 is movable within aperture 138 and
interacts with first and second detents 137A, 137B to provide
locking positions for the mulch door 124. Compression spring 135 is
arranged between spacer 134 and knob 131 and acts to bias the knob
131 to be in the positions defined by detents 137A, 137B. In order
to rotate the mulch door 124, a user pushes on knob 131 to compress
the compression spring 135 and release the pin 136 from one of the
detent positions. The knob 131 can then be freely rotated to
another position.
[0071] As described above, with the mulch door 124 in the discharge
position grass clippings and other waste will travel through the
discharge passage 122 and out of the discharge port 123 during
operation of mower 10. This waste can either be collected in
collection bag 80 or be discharged.
[0072] In order to permit rear discharge of grass clippings/waste
while preventing the clippings from striking a user of mower 10, a
discharge door 127 can be coupled to deck 50. FIG. 26 shows a
discharge door 127 attached to the rear of the mower 10 to deflect
grass clippings/waste from the discharge passage 122 downwardly.
Discharge door 127 can be U-shaped or otherwise constructed such
that discharge door 127 defines a discharge cavity 128 to provide
the space necessary for the passage of the clippings. The discharge
door 128 can include an angled portion 127A that directs the flow
of grass clippings/waste out of the bottom of the discharge cavity
128. In order to collect grass clippings/waste, collection bag 80
can be coupled to deck 50 as is known in the art, for example, by
lifting discharge door 127, as illustrated in FIGS. 21 and 23.
[0073] Mower 10 includes a blade motor 54 for driving blade 16 and
a drive motor 56 for imposing motion onto drive wheel(s) 30 in
order to propel the mower 10. The blade and drive motors 54, 56 can
be operated independently. That is, the blade 16 can be powered by
the blade motor 54 without the drive motor 56 propelling the mower
10 and the drive motor 56 can be powered to propel the mower 10
without the blade motor 54 driving the blade 16.
[0074] Drive motor 56 may be coupled to driving wheel(s) 30 through
at least one gear mechanism. However, the present exemplary gear
mechanism shown in FIG. 20 is a multi-stage gear reduction having a
planetary gear assembly 57, a self-drive transmission 58, a drive
axle gear 59A, and a wheel gear 31. The planetary gear assembly 57
and a self-drive transmission 58 translates a rotational output of
the drive motor 56 into a rotational output of a drive axle 59
coupled to drive wheel(s) 30. The self-drive transmission 58 is a
worm gear that engages the drive motor 56 (through planetary gear
assembly 57) to the drive wheel(s) 30 during self-drive operation,
while permitting free-wheeling operation when the drive motor 56 is
not powered. The drive axle 59 is coupled to the drive wheel(s) 30
through a drive axle gear 59A that interacts with a wheel gear
31.
[0075] The gear mechanism provides a gear reduction from the drive
motor 56 to the drive wheels 30 to translate the revolutions per
minute ("rpm") of the drive motor 56 to the drive speed of the
motor (the rpm of the drive wheels 30). The drive motor 56 can
operate between 6,000 and 17,000 revolutions per minute and the
gear mechanism can have a gear reduction between 90:1 and 130:1,
for example. The planetary gear assembly 57 provides a first gear
reduction (a planetary gear reduction) from drive motor 56, while
self-drive transmission 58 provides a second gear reduction (a worm
gear reduction). Additionally, the gear ratio of the drive axle
gear 59A and wheel gear 31 can provide a third reduction. For
example only, the first gear reduction can be 3.67:1, the second
gear reduction can be 9:1 and the third gear reduction can be
3.25:1 to provide a total gear reduction from drive motor 56 to
wheel(s) of 107.3:1. In this example, if the drive motor 56
operates at 10,000 revolutions per minute and the drive wheel(s) 30
diameter is 9 inches, the maximum drive speed of mower 10 will be
approximately 2.5 miles per hour.
[0076] During operation of mower 10, the blade and drive motors 54,
56 generate heat and may need to be cooled. For example, as shown
in FIGS. 28 and 29, blade motor 54 is coupled to deck 50 with a
first end 54A arranged within a chamber 90 defined by deck 50 and a
second end 54B coupled to the blade 16 in the cutting chamber 120.
Blade motor 54 is configured to be cooled by a flow of air entering
the first end 54A from the cooling chamber 90 and exiting from the
second end 54B into the cutting chamber 120. Air can enter chamber
90, e.g., through one or more windows 92 defined by deck 50 to
provide a vent to external air, as described more fully below. In
this manner, the blade motor 54 is configured to convey air from
the chamber 90 to the cutting chamber 120 in order to cool the
blade motor 54.
[0077] Drive motor 56 is arranged adjacent the rear wheels in a
second chamber 91 defined by the deck 50. Due to its location
behind the battery, the limited space of this second chamber 91
makes cooling the drive motor 56 difficult. Therefore, the second
chamber 91 includes one or more windows 92 that allow air in the
second chamber 91 to escape into an air passageway connected to the
first chamber 90. The air passageway is defined by the deck 50 and
shroud 13 (not shown in FIG. 28) and is located to the side of the
battery in FIG. 28.
[0078] Air in the first chamber 90 is then vented to the external
environment through blade motor 54. Additionally, operation of the
blade motor 54 will create negative pressure in the first chamber
90 relative to the second chamber 91 and generate an air flow from
the second chamber 91 to help cool the drive motor 56.
[0079] In some embodiments, control circuit 20 can be configured to
protect the mower 10 from an electrical overload condition, such as
a short circuit. Upon detection of an overload condition, the
control circuit 20 will electrically disconnect the battery 12 from
the drive motor 56. An overload condition can include the situation
in which current provided to the drive motor 56 exceeds a
threshold. Alternatively or in addition to current exceeding a
threshold, an overload condition can include current exceeding a
threshold for a predetermined period. In some embodiments, an
overload condition can include current exceeding a second threshold
for a second predetermined period, in which the second threshold is
greater than the first threshold and the second predetermined
period is shorter than the first predetermined period. For example
only, an overload condition can be defined as a condition in which
current delivered to the drive motor 56 is greater than 10 amperes
but less than 15 amperes for a period of 5 or more seconds, or
greater than 15 amperes for a period of 1 or more seconds. While
the above description is limited to describing an overload
condition for the drive motor 56, it will be appreciated that an
overload condition for blade motor 54 is also within the scope of
the present disclosure.
[0080] In addition to overload protection, control circuit 20 can
be configured to provide a soft-start to drive motor 56 in order to
reduce or eliminate abrupt movement (or "jump") of the mower 10 at
the beginning of self-drive operation. In some embodiments, upon
actuation of the drive bail 102 the control circuit 20 will
gradually increase the voltage provided to drive motor 56 until
reaching the desired operating voltage, e.g., the operating voltage
determined by the position of speed control lever 108. For example
only, control circuit 20 will increase the voltage provided to
drive motor 56 over a predetermined period, such as 1-3
seconds.
[0081] In some embodiments, the handle assembly 100 is capable of
being rotated in relation to the deck 50 in order to "fold" the
handle assembly 100 over the deck 50 to reduce the size of mower 10
for storage. For example and with reference to FIGS. 23, 30 and 31,
two handle plates 200 fixedly coupled to deck 50 can be utilized to
couple the handle assembly 100 with the deck 50. Handle frames 103
can be rotatably coupled to handle plates 200 by fasteners 201,
such as a nut and bolt. A knob assembly 210 that is offset from the
fasteners 201 can interact with one or more openings 202A-C defined
by handle plates 200 to inhibit rotation of the handle assembly
100. Openings 202A and 202B are utilized to lock the handle
assembly 100 in the proper position for operation of mower 10.
Openings 202A and 202B each correspond to a different position of
handle assembly 100, which can be selected based on user
preference. Opening 202C corresponds to a storage position in which
handle assembly 100 is folded over deck 50. The storage position
(FIG. 31) of handle assembly 100 permits mower 10 to be stored
vertically, e.g., with a contact portion 205 of handle plates 200
in resting on a storage surface.
[0082] With specific reference to FIG. 30, an exemplary knob
assembly 210 includes a graspable knob 212 that is coupled with an
extension peg 214 by a pin 216 inserted into an opening 218 defined
by graspable knob 212. Extension peg 214 can be biased to an
extended or locked position, e.g., by a spring, in which knob
contact surface 213 contacts handle frame 103 and extension peg 214
is extended, e.g., into openings 202A-C. In order to release
extension peg 214 from opening 202A, 202B or 202C, a user pulls on
graspable knob 212. Furthermore, rotation of graspable knob 212 can
move the knob assembly 210 to a released position in which
extension peg 214 is retracted such that extension peg 214 does not
interact with opening(s) 202A-C and the handle assembly can be
freely rotated. For example only, graspable knob 212 can define an
aperture 215 that interacts with a projection 106 formed on handle
frames 103. The shape of aperture 215 can complement the shape of
projection 106 to inhibit rotation of the graspable knob 212 in the
locked position and to secure the knob assembly in the released
position when the graspable knob 212 is rotated.
[0083] While the disclosure has been described in the specification
and illustrated in the drawings with reference to various
embodiments, it will be understood by those skilled in the art that
various changes may be made and equivalents may be substituted for
elements thereof without departing from the scope of the disclosure
as defined in the claims. Furthermore, the mixing and matching of
features, elements and/or functions between various embodiments is
expressly contemplated herein so that one of ordinary skill in the
art would appreciate from this disclosure that features, elements
and/or functions of one embodiment may be incorporated into another
embodiment as appropriate, unless described otherwise above.
Moreover, many modifications may be made to adapt a particular
situation or material to the teachings of the disclosure without
departing from the essential scope thereof. Therefore, it is
intended that the disclosure not be limited to the particular
embodiments illustrated by the drawings and described in the
specification as the best mode presently contemplated for carrying
out this disclosure, but that the disclosure will include any
embodiments falling within the foregoing description and the
appended claims.
* * * * *