U.S. patent number RE30,686 [Application Number 05/967,719] was granted by the patent office on 1981-07-21 for remote starting system for a combustion engine.
Invention is credited to Jeffry C. Bucher.
United States Patent |
RE30,686 |
Bucher |
July 21, 1981 |
Remote starting system for a combustion engine
Abstract
A system is disclosed for enabling a user to start an engine
from a remote location, utilizing a receiver for receiving a
command signal from a remote transmitter operated by the user, the
receiver generating signals to control operation of the starting
system. The system enables the user, from the remote location, to
effect selective momentary pumping of fuel into the engine prior to
activation of the starting operation, and then to start the engine.
The system may include apparatus for maintaining the throttle of
the engine substantially open until the engine is started and then
closing the throttle to an idling position, with automatic
momentary pumping of additional fuel into the engine at
predetermined intervals during the running of the engine in
accordance with the starting operation. Protective apparatus may be
included with the system to prevent activation of the starting
operation at any time a manually controlled starting switch has
been activated prior to activation of the starting system.
Additional protective devices may be included to prevent improper
activation of the momentary fuel feed apparatus by the user after
the engine has been started, and to stop the engine upon the
occurrence of any of several predetermined events, including
excessively prolonged activation of the starter motor without
starting of the engine, opening the door or applying the brake of
the vehicle in which the system and engine may be installed, or the
idling of the engine for a predetermined period of time under
control of a starting system.
Inventors: |
Bucher; Jeffry C. (Aspers,
PA) |
Family
ID: |
27094319 |
Appl.
No.: |
05/967,719 |
Filed: |
December 8, 1978 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
Issue Date |
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Reissue of: |
643664 |
Dec 23, 1975 |
04080537 |
Mar 21, 1978 |
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Current U.S.
Class: |
290/38R;
123/179.2; 290/37A; 290/37R; 290/38C |
Current CPC
Class: |
F02N
11/0807 (20130101); F02D 28/00 (20130101) |
Current International
Class: |
F02D
28/00 (20060101); F02N 11/08 (20060101); H02P
009/04 () |
Field of
Search: |
;290/37R,37A,38R,38A,38B,38C,38D,38E,DIG.1,DIG.3 ;123/179B |
References Cited
[Referenced By]
U.S. Patent Documents
Primary Examiner: Dobeck; B.
Attorney, Agent or Firm: Birch; H. J.
Claims
I claim:
1. A system to enable a user to start, from a remote location, a
combustion engine having an electric starter motor and a source of
electrical potential associated therewith, said system
comprising:
a receiver for receiving a control signal selectively generated by
said user;
means coupled to said receiver and responsive to selective,
repetitive receptions of said control signal for selective,
repetitive, user-controlled pumping of fuel into said engine prior
to activation of a starting operation; .[.and.].
means also coupled to said receiver and responsive to the last of
said receptions of said control signal for activating said starting
operation and connecting said potential source to said starter
motor.Iadd.; and
means for preventing any said selective pumping by said user after
said starting operation has been activated until said starting
operation has been terminated.Iaddend..
2. A system according to claim 1 further comprising means for
activating desired auto accessories concurrently with said pumping.
.[.3. A system according to claim 1 further comprising means for
preventing any said selective pumping by said user after said
starting operation has been
activated until said starting operation has been terminated..]. 4.
A system according to claim 1 further comprising means for
maintaining the throttle of said engine substantially open during
said starting operation until said engine has been started and then
closing said throttle to an idling position, whereby additional
fuel may be provided to said engine during the initial portion of
the starting operation which avoiding
overspeeding the engine once started. 5. A system according to
claim 1 further comprising means for automatically effecting
momentary pumping of fuel into said engine at a plurality of
predetermined intervals during said starting operation. .[.6. A
system according to claim 1 further comprising means for preventing
any said pumping of fuel into said engine,
by user operation of said system, while said engine is running..].
7. A system according to claim 1 wherein a manually operated switch
is interposed between said source of electrical potential and said
starter motor, and further comprising means for disabling said
starting operation
activating means when said manually operated switch is activated.
8. A system according to claim 7 further comprising protective
means for preventing activation, by any signal within said system,
of any momentary
fuel pumping means while said disabling means is activated. 9. A
system according to claim 1 further comprising protective means for
preventing activation of said starting operation by externally
generated electrical transients and noise, said protective means
comprising a capacitor connected, with its polarity reversed,
between the emitter and base of a transistor in said starting
operation activating means with a resistor
connected across said capacitor. 10. A system according to claim 1
further comprising means to stop said engine upon receipt of said
control signal
from said user at said remote location. 11. A system according to
claim 1 further comprising means for de-energizing said starting
operation activating means and disconnecting said potential source
from said starter motor if the engine does not start within a
predetermined time after said potential source is connected to said
starter motor by said starting
operation activating means. 12. A system according to claim 1
further comprising means for de-energizing said starting operation
activating means and stopping the engine after the engine has been
started and has run in accordance with said starting operation for
a predetermined period
of time. 13. A system according to claim 1 further comprising means
to detect starting of said engine and to disconnect said potential
source from said starter motor upon said starting, and to detect
subsequent stalling of said engine during said starting operation
and to reconnect said potential source to said starter motor
subsequent to said stalling.
Description
BACKGROUND OF THE INVENTION
The present invention is an improvement of the remote starting
system disclosed in U.S. Pat. Nos. 3,478,730 and 3,793,529. The
systems disclosed in those previous patents were substantial
improvements over the known devices for starting an engine from a
remote location, and the system disclosed herein incorporates
certain desirable additional features and improvements. The
aforesaid patents set forth the background of the invention in
detail, including citations of prior art of interest. Subsequently
issued U.S. Pat. No. 3,685,606 also is of interest, but does not
disclose or suggest the novel features and attendant advantages of
the system disclosed herein.
SUMMARY OF THE INVENTION
The system of the invention enables a user to start, from a remote
location, an engine having an electric starter motor and a source
of electrical potential associated therewith, such as, an
automobile or truck engine. The starting system utilizes a receiver
for receiving a coded control signal from the user at a remote
location. The system further comprises an energizing circuit
coupled to the control signal receiver and including means for
activating a programmed starting operation in response to such a
control signal and connecting the potential source to a starter
motor. Apparatus is provided for selective, user-controlled
momentary pumping, from such remote location, of fuel into the
engine prior to activation of the starting operation.
The system may further include sequencing apparatus for activating
the starting operation after such user-controlled momentary pumping
of the fuel has stopped for a predetermined period of time, and
protective apparatus for preventing any undesired momentary pumping
of fuel by the system, and additional protective apparatus may be
incorporated to prevent activation of the starting operation by
spurious signals.
DESCRIPTION OF THE DRAWING
FIGS. 1 and 1A are schematic diagrams of a preferred embodiment of
the remote starting system of this invention.
DESCRIPTION OF A PREFERRED EMBODIMENT
The remote starting system of this invention, one embodiment of
which is illustrated in the schematic diagram of FIG. 1, includes a
plurality of interconnected timing and protective devices which
provide control signals for starting an engine in response to a
remotely transmitted control signal. The system provides for
selective user-controlled momentary pumping of fuel into the
engine, such as for priming, prior to starting and for automatic
momentary pumping of fuel at predetermined intervals during the
starting operation, with protective devices preventing unintended
momentary pumping of fuel. Other apparatus provides for stopping
the engine upon a subsequent command from the remote signal
transmitter or upon the occurrence of any one of a number of
malfunctions or other predetermined events. The system is described
with respect to a conventionally carbureted, spark ignition
internal combustion engine; however, it is equally applicable to
fuel injected engines, diesel engines and other types of combustion
engines.
In the preferred embodiment of this system a signal receiver is
mounted in a vehicle to receive a coded control signal from a
signal transmitter carried by a user. The receiver and transmitter
may desirably be radio units of the type disclosed in the
aforementioned U.S. Pat. No. 3,478,730, or may be of other types,
either radio-linked, wire-connected, or of any other suitable type.
The system control signal from the receiver initially effects the
momentary pumping of fuel into the engine and the connecting of a
source of electrical potential to the ignition system, and then,
after a predetermined delay, activates the actual starting
operation, connecting the electrical potential source to the
starter motor. The system includes novel protective means for
preventing improper activation by spurious signals and externally
generated electrical noise.
The main power supply line for the system, designated MAIN B+, is
connected at all relevant times after installation of the system,
for example, in an automobile, to a potential source such as a
conventional automobile battery. The diamond-shaped symbols on the
schematic represent plug connections. The numbers 1-8 immediately
adjacent broken line X--X on FIG. 1B represent continuations of the
connections denoted by numbers 1-8 immediately adjacent broken line
X--X on FIG. 1A. The signal receiver, referenced above, is not
shown in its entirety on the schematic since its only function is
to provide control signals to the system. This control function is
effected by utilizing the signal received by its receiver to close
a relay K2, illustrated in the schematic, at any time a control
signal is sent to the receiver, and to maintain that relay closed
for the duration of the signal. Such signals are sent by the user
activating a momentary command switch on the transmitter, the
duration of the signal corresponding to the duration of activation
of such switch by the user. K2 is a relay activated by the radio,
one side being connected to ground and the other connected to R9.
R9, in turn, is connected to the base of PNP transistor Q10 and to
MAIN B+ source through resistor R8. When relay K2 is closed, by a
control signal from the receiver, a ground path is established from
MAIN B+ to resistors R8 and R9, thus biasing and turning on
transistor Q10 and applying MAIN B+ current to the anodes of diodes
D6 and D1 for the duration of the control signal.
If desired, the cathode of diode D1 may be connected to apply
potential to a warning device such as the automobile horn, thus
providing for a brief blast to signal energization of the starting
system. The energization of diode D6 also provides biasing current
to the base of NPN transistor Q5, which is connected between the
cathode of diode D6 and ground. This application of bias current
turns on transistor Q5, thus establishing a ground path through its
emitter-collector circuit and through resistor R17 to the base of
PNP transistor Q11, which in turn is connected to the potential of
the MAIN B+ line. Thus, biasing potential is also applied to the
transistor Q11, turning it on and establishing an additional
biasing path between the MAIN B+ line and the base of transistor
Q5. This arrangement provides a latching circuit to keep
transistors Q11 and Q5 turned on until affirmatively switched off
by a subsequent predetermined event.
To prevent inadvertent activation of this starting operation by
externally generated electrical transients and spikes, capacitor
C10 is installed between MAIN B+ and the base of transistor Q11.
The noise suppression effect of this capacitor has been found most
effective when the capacitor is installed with its polarity
reversed, that is, with its normally negative contact connected to
the positive MAIN B+ line and its normally positive contact
connected to the base of transistor Q11. Surprisingly, and for
reasons not fully understood, this reversed-polarity installation
of capacitor C10, with suppression resistor R16 connected across
the capacitor, has been found to be highly effective in preventing
activation of the system by spurious signals and externally
generated noise present in the potential used with this system.
Installation of capacitor C10 with a conventional polarity
configuration has been found to be substantially less
satisfactory.
The value of capacitor C10 is selected so that under normal
operating conditions, the voltage across the capacitor never
exceeds its breakdown potential. In a system for a typical
automobile engine, employing a 12 volt battery potential source,
the voltage across capacitor C10 normally is 0.4 volt and does not
exceed 0.7 volt, unless other components of the system fail first.
For such a system, capacitor C10 is selected to have a breakdown
potential of at least 2 volts.
Upon the application of the MAIN B+ potential to diode D6, and the
latching, within a few nanoseconds, of transistors Q5 and Q11, the
B+ potential is applied to diode D8, thus providing MAIN B+
potential at the cathode of diode D12 and preventing a grounding
path from diode D12 through resistor R30, for a purpose that will
become more apparent subsequently.
Connected between ground and the cathode of diode D6 and collector
of transistor Q11 is the base NPN transistor Q4. Thus, application
of MAIN B+ potential to diode D6, or through the emitter-collector
circuit of transistor Q11, provides a biasing potential to the base
of transistor Q4, thus turning on transistor Q4 and establishing a
grounding path through its emitter-collector circuit for the low
side of the coil of relay K1. The energization of the coil of relay
K1 then pulls in the relay, closing its contacts within a few
milliseconds of the energization of transistor Q4. The dual sources
of MAIN B+ potential available to transistor Q4, either from the
cathode of diode D6 or from the collector of transistor Q11,
maintain the bias, and thus activation, of transistor Q4 and keep
closed the contacts of relay K1 as long as either or both of
transistors Q10 and Q11 are activated. The closing of the contacts
of relay K1 then applies electrical potential, suitably +12 volts
from the automobile battery, both to the STARTING B+ line and to
the ignition system (IGNITION) and to any desired accessories (ACC)
associated with the engine, for example, the headlights or heater
of an automobile. These accessories will thus remain activated as
long as the system maintains the contacts of relay K1 closed.
At this point, the system is fully energized, with both MAIN B+ and
STARTING B+ potential applied. However, the initiation of the
actual starting operation of the engine is delayed for a brief
period after the initial energization, in a manner and for reasons
to be described below. For purposes of this invention, the term
"starting operation" includes both the actual cranking and starting
of the engine and the running of the engine for a predetermined
period of time under the control of the starting system.
The activation of the latching circuit containing transistors Q11
and Q5 also provides potential to diode D11, connected between the
collector of transistor Q11 and a voltage dividing network
comprising voltage stabilizing capacitor C8 and resistors R22, R23,
R24, R25, R26, R27, R28 and R29. This now-energized voltage
dividing network provides reference voltages to the gates G of
unijunction transistor timing devices U1, U2, U3 and U4.
Programmable unijunction transistor timing device U1 provides for
the desired brief delay between the initial energization of the
starting system and the initiation of the actual starting
operation. Since the anode A of unijunction U1 is connected at all
times to MAIN B+ through an R-C delay circuit comprising resistors
R31, R32, R33 and capacitor C1, the charging of capacitor C1 and
its associated timing is initiated at the instant the reference
voltage is applied to the gate G of the unijunction from voltage
dividing network R22-R23. The values of resistors R31, R32 and R33
and capacitor C1 are selected to provide the desired delay,
suitably five seconds. It may be noted, however, that the anode of
unijunction U1 is also connected, through diode D3 to the high side
of receiver relay K2. Thus, whenever the contacts of relay K2 are
closed, providing a path to ground in response to a receiver
control signal, the anode A of delay timer U1 is grounded, thus
preventing the initiation of the five second timing delay on U1 and
preventing U1 from completing its timing out and activating, if it
has begun. Accordingly, repeated keying of the transmitter by the
user at intervals of less than five seconds will prevent the
initiation of the starting operation, even after the circuit has
been energized.
By the provision of this repeatably resettable five second delay by
U1, the system facilitates repeated momentary pumping of fuel into
the engine, such as for pre-start priming, by the user from the
remote location in the following manner. As previously described,
upon keying the transmitter and sending a control signal to the
receiver and thus closing the contacts of relay K2, transistor Q10
is turned on, thus providing MAIN B+ potential at its collector.
Resistors R3 and R4 are connected in series to the collector of
transistor Q10 and to the base of NPN transistor Q7, thus providing
biasing potential and turning on transistor Q7. Resistor R5 (and
resistors R54 and R55) is provided for additional noise
suppression. The activation of transistor Q7 then establishes a
grounding path across its emitter-collector circuit to resistor R42
and thence to the base of transistor Q14. The connection of the
base of transistor Q14 to STARTING B+ through resistor R41 thus
provides biasing potential to turn on transistor Q14, thereby
establishing a path across its emitter-collector circuit from
STARTING B+ through diode D21 to GAS SOL. GAS SOL is a device such
as a solenoid connected to the throttle linkage of the engine. In a
conventionally carbureted engine this solenoid, GAS SOL, is
connected to the carburetor accelerator pump and to the carburetor
butterfly valve such that activation of GAS SOL provides for a
momentary pumping of fuel by the accelerator pump and also holds
the carburetor butterfly valve open for the duration of such
activation. Thus, upon the closing of the contacts of relay K2 by a
signal from the user, GAS SOL may be activated, effecting a
momentary pumping of fuel into the engine. As described above, if
this signal and its resulting activation of GAS SOL is repeated at
intervals of less than five seconds, this user-controlled momentary
pumping of fuel into the engine may be repeated as long as desired
prior to the initiation of the starting operation. Similarly,
termination of this activation of GAS SOL by the user for a period
of more than five seconds will permit unijunction U1 to time out
and begin the system starting operation.
When unijunction U1 has so timed out, the potential from MAIN B+
through the aforementioned R-C circuit will then be provided at the
cathode C of unijunction U1, to which the base of NPN transistor Q6
is connected. Thus, a biasing potential is provided to transistor
Q6, turning it on and providing a grounding path both for resistor
R36 connected to the base of PNP transistor Q12, and for diode D20
and resistor R42 connected to the base of PNP transistor Q14, all
of this occurring immediately after the five second delay effected
by unijunction timer U1. Since the base of transistor Q12 is
connected to STARTING B+ potential through resistor R35 and to
ground through resistor R36 and transistor Q6, Q12 thus will also
be turned on. The connection of the emitter of transistor Q12 to
STARTING B+ potential and the collector of Q12 to diode D17 and
resistor R37 and thence to the anode of unijunction U1 thereby
provides an additional source of potential into unijunction U1.
Thus, a latching circuit is effected which keeps transistors Q6 and
Q12 and unijunction U1 turned on until deactivated by a subsequent
predetermined event. Resistor R41 is connected between STARTING B+
potential and the base of PNP transistor Q14. Since the activation
of transistor Q6 provides a grounding path between the base of Q14
through resistor R42 and diode D20, the activation of transistor Q6
also turns on transistor Q14. As previously described with respect
to transistor Q7, the activation of transistor Q14 also activates
GAS SOL. As previously described, the activation of GAS SOL
provides a momentary pumping of fuel into the engine and also holds
the throttle or butterfly valve of the carburetor open as long as
transistor Q14 remains activated.
At the same time that the fuel feed device GAS SOL is being
activated by transistors Q6 and Q14, the activation of transistor
Q12 provides a positive potential from its collector through diode
D18 to the starter solenoid, denoted as START SOL, thereby applying
potential to the starter motor and beginning the cranking of the
engine. Diode D29, and corresponding diode D30, are suppression
diodes between START SOL and ground and between GAS SOL and ground,
respectively. Thus, by the arrangement of the START SOL and GAS SOL
circuitry, it can be seen that, five seconds after the starting
system (and ignition system) is energized, there will be momentary
pumping of gas into the engine with the throttle held substantially
open, and then electrical potential will be provided to the starter
motor for cranking the engine. Under normal circumstances this will
quickly result in the starting of the engine.
Once the engine has started it is desirable both to de-energize the
starter motor by de-energizing START SOL and also to close the
throttle back to an idle position, by de-energizing GAS SOL. This
function may suitably be performed by detecting the output of the
alternator (or generator) associated with the engine. Once the
engine has started and accelerated, the alternator will begin its
generation of current. As seen in the diagram, zener diode D1 and
diode D4 are connected in series between the alternator and the
bases of NPN transistors Q1 and Q2. Thus, when the engine has
accelerated to a speed at which the alternator has reached a
predetermined electrical output, conveniently about 7.2 volts,
zener Z1 will break down and conduct, thus turning on transistors
Q1 and Q2. The emitter of Q1 is connected to ground and the
collector thereof to the anode of programmable unijunction timer
U1. Accordingly, when transistor Q1 is turned on by the alternator,
the anode of timer U1 is grounded, thus causing U1 to drop out,
and, accordingly, turning off transistor Q6. The deactivation of
transistor Q6 then breaks the ground path from resistor R36 and
from diode D20 and resistor R42, thus removing the bias from and
turning off transistors Q12 and Q14. As a result, both START SOL
and GAS SOL are de-energized, thereby de-energizing the starter
motor and permitting the throttle to close back to an idling
position before the engine overspeeds and causes any damage to
itself or to the starter motor.
If the engine starts, but then stalls and dies, the output from the
alternator will terminate, thus removing the potential from the
cathode of diode D4. This condition then removes the biasing
potential from transistors Q1 and Q2, turning off those transistors
and interrupting their emitter-collector circuits to ground. Thus,
the anode of unijunction timer U1 is no longer grounded, and U1 is
permitted to begin its timing-out sequence once again, with the
system-controlled activation of START SOL and GAS SOL occurring
once again. If the engine then starts and then dies again, this
system will repeat this procedure and attempt another restart. Once
the engine has started properly and is running under system
control, the apparatus and its procedure described in the preceding
paragraph will once again ground the anode of U1 and deactivate
START SOL and GAS SOL, all as previously described.
At this point, in normal operations, the engine will be running,
preferably at a fast idle to speed its warm-up. Accordingly, after
a period of time, it is desired to reduce the speed of idle, such
as is commonly done by a driver tapping the accelerator pedal of an
automobile. This function is achieved by periodic momentary
activation of GAS SOL at a plurality of predetermined intervals
during the starting operations. It has been found that activation
of GAS SOL at approximately four minute intervals over an
approximate twelve minute starting operation is desirable. Thus, an
R-C circuit comprising resistor R38 and capacitor C2 is connected
between the MAIN B+ line and the anode A of programmable momentary
unijunction timer U2, with parameters chosen to provide for
approximtely four minute, periodic, momentary activation of timer
U2. Capacitor C5 connected between the anode and gate of timer U2
represents a portion of the programming apparatus. Thus,
approximately four minutes after the starting system is energized
and an appropriate reference voltage is applied to the gate G of
unijunction U2, it times out and provides a potential at its
cathode C and thus to the base of NPN transistor Q7. The timing out
of unijunction U2 thus momentarily activates transistor Q7 at four
minutes intervals. Since resistor R42, connected to the base of
transistor Q14, is also connected to the collector of transistor
Q7, the activation of transistor Q7 provides a biasing path for
electrical potential to the base of Q14, independent of the
above-described activation and deactivation of transistor Q6. Thus,
when timer U2 is momentarily activated, GAS SOL is likewise
momentarily activated, providing a momentary pumping of fuel into
the engine in a manner similar to a driver tapping the accelerator
pedal of an automobile. Upon activation and deactivation of U2,
caused by the discharge of previously charged capacitor C2, it can
be seen that the four minute charging of capacitor C2 will begin
again, thus providing for another momentary activation of GAS SOL
approximately four minutes later. This operation will be repeated
at the predetermined intervals as long as the circuit is activated,
thus facilitating the transition of the engine from its initial
fast idle to its standard idling speed. It may be noted that the
values of resistor R38 and capacitor C2 are selected to provide for
the desired activation period of timer U2. The structure of timer
U2 provides for the desired length of activation of GAS SOL upon
each timing out of timer U2.
With the engine started and idling properly it is desirable that
the engine be allowed to run only for a predetermined time, such as
twelve minutes, to provide for thorough warm-up but avoiding
unnecessarily prolonged idling. Accordingly, a circuit is provided
to enable this starting operation to shut down the starting system
and turn off the engine after it has started and run in accordance
with the starting operation for such predetermined period. This
timing circuit is associated with programmable unijunction
transistor timer U3. In a manner similar to that described with
respect to timer U2, an R-C circuit comprising resistor R43 and
capacitor C3 is connected between the MAIN B+ line and the anode of
unijunction U3. The values of resistors R43 and C3 are selected to
provide the desired running period of the engine, such as twelve
minutes, before timing out and activating timer U3. Capacitor C6,
connected between the anode and the gate of unijunction U3,
represents an additional portion of the time delay programming of
the timing unijunction U3. When the predetermined period of time
has elapsed and capacitor C3 discharges, unijunction U3 times out,
providing a potential at the cathode of U3, which is connected
through R51 to the base of NPN transistor Q8, the base also being
connected to ground through resistor R53. This potential turns on
transistor Q8, establishing a circuit from the collector through
the emitter to ground. The collector of Q8 is connected to the
cathode of diode D10, which is connected into the previously
described Q11-Q5 latching circuit between resistors R18 and R19 and
ahead of the base of transistor Q5. Accordingly, when transistor Q8
is turned on, the cathode of diode D10 will be grounded, thus
shorting the potential away from the base of Q5, turning off
transistor Q5 and thus breaking the circuit to ground between the
cathode of transistor Q5, resistor R17 and the base of transistor
Q11. Accordingly, transistor Q11 is likewise turned off, breaking
its emitter-collector circuit between MAIN B+ line, through
resistor R6 to the base of transistor Q4. Consequently, transistor
Q4 is also turned off, de-energizing the coil and opening the
contacts of relay K1 and breaking the circuit between the battery
and the ignition system (IGNITION) of the engine as well as from
the STARTING B+ line. Accordingly, with the ignition circuit open,
the engine is shut down. If the apparatus were utilized in a diesel
engine, the IGNITION connection may suitably be replaced with a
connection controlling the operation or disabling of the fuel
injection, or other component, similarly providing for
shutdown.
The starting system also provides for shutting down the engine in
response to a control signal sent by the user to the receiver. This
shutdown operation is performed in a manner analogous to that
previously described. With the engine running, the output of the
alternator maintains transistor Q2 in an activated condition, with
a circuit established from the collector through the emitter to
ground. The collector of Q2 is connected to the emitter of NPN
transistor Q3, with the collector of Q3 connected between resistors
R18 and R19. The base of transistor Q3 is connected to ground
through resistor R11 and to the cathode of diode D1 through
resistor R10. As described above, when a control signal is sent to
the receiver, the contacts of normally open relay K2 are closed and
held closed for the duration of the signal. The closing of the
contacts of relay K2 provides bias to the base of transistor Q10,
thus providing potential from MAIN B+ to the anodes of diodes D1
and D6. This potential is then applied through resistor R10 to the
base of transistor Q3, turning on transistor Q3 and thus grounding
resistor R18 through transistor Q2. As previously described with
respect to the activation of transistor Q8, the grounding of
resistor R18 turns off transistors Q5 and Q11, thus removing the
circuit through Q11 as a source of potential for activating
transistor Q4, which maintains the contacts of relay K1 closed.
However, it may be seen that as long as the contacts of relay K2
are held closed by the control signal from the receiver, thus
keeping transistor Q10 turned on, a secondary source of potential
exists from MAIN B+ through diode D6 to the base of transistor Q4.
Accordingly, as long as the user keys the transmitter, thus
activating the receiver and holding the contacts of relay K2
closed, the contacts of relay K1 will remain closed, maintaining
+12 volt power to IGNITION and allowing the engine to continue
running. However, upon release of the transmitter key, the control
signal holding the contacts of relay K2 closed will be removed,
breaking that circuit and turning off transistor Q10, thus removing
all sources of biasing potential from transistor Q4 and causing
relay K1 to open, thus de-energizing the ignition system and
stopping the engine. Accordingly, it can be seen that sending a
control signal to the starting system while the system is in
operation and the engine is running will provide for a
user-controlled shutdown of the engine and de-energization of the
starting system.
When the engine has shut down, it is desirable to bleed off all
reference voltages from the unijunction programmable timers in
order to reset all such timers prior to subsequent activation of
the system, so that a subsequent starting operation may proceed in
its desired order. As noted above, the network for providing the
reference voltages to the programmable unijunction timers includes
voltage dividers R22-R23, R24-R25, R26-R27 and R28-R29, with
capacitor C8 connected in parallel with each of those voltage
dividers. This capacitor C8, which is connected through diode D11
and transistor Q11 to the MAIN B+ potential, is included to
maintain a constant voltage across the voltage dividing network
despite transients in the system, such as caused by the activation
of the starter motor or other accessories. The capacitor C8
provides the reference voltage network wiitth a relatively constant
voltage for a period of several seconds despite the imposition of
such transients upon its source. However, upon shutdown it is
necessary to bleed off the voltage of C8 in order to reset the
programmable unijunction timers. This bleed-off is achieved by
activation of transistor Q8 in the following manner. As noted
above, when the user shuts down the engine by a signal instead of
allowing completion of the full twelve minute starting operation,
transistors Q11 and Q5 are turned off, thereby removing the
potential from diode D8 and thus from the cathode of diode D12, all
in a few nanoseconds from the timer relay K2 is closed by the
receiver signal. However, for at least a few additional
milliseconds, the contacts of relay K1 will remain closed,
providing power to the STARTING B+ line. Thus, potential is
available to the base of transistor Q15 through resistor R49. Since
there is no longer a positive potential applied at the cathode of
D12, a grounding path may be established from the base of PNP
transistor Q15 through resistor R50, zener Z2, diode D12 and
resistor R30. Accordingly, the potential applied through resistor
R50 quickly breaks down zener Z2, causing it to conduct and thus
establishing a ground path from the base of transistor Q15, turning
on that transistor. The activation of transistor Q15 then provides
a potential through its emitter-collector circuit to the base of
NPN transistor Q8, turning on that transistor and establishing a
grounding path through its emitter-collector circuit. A resistor
R21 is connected between the cathode of diode D11 and the collector
of transistor Q8, such that the aforementioned activation of
transistor Q8 grounds resistor R21, bleeding off any residual
potential in capacitor C8. The previously described deactivation of
transistor Q11 and Q5 and the discharge of capacitor C8 thus
removes all reference voltages from the programmable unijunction
timers, resetting them to the beginning of their respective timing
cycles.
As additional protective devices this remote starting system is
provided with apparatus to shut down the engine and disable the
system upon the occurrence of any one of a number of preselected
events. For example, if the starter motor cranks the engine for a
predetermined period of time without the engine starting, it is
desirable to have the starting system cease cranking in order to
avoid excessive discharge of the battery and possible damage to the
starter motor. Accordingly, apparatus is provided in this system to
deactivate the starting operation if cranking continues for more
than a predetermined period, for example, ten seconds. This
protective apparatus is associated with programmable unijunction
transistor timer U4 in the circuit. It may be seen that the anode
of unijunction U4 is connected, through resistor R45, to the
cathode of diode D22, thus providing potential from the STARTING B+
line to the anode of unijunction U4 at any time that START SOL is
energized. Capacitor C4 is connected between the anode of
unijunction U4 and ground, the charging thereof through resistor
R45 providing for the desired delay of, suitably, ten seconds from
the energization of START SOL until the activation of unijunction
U4. After that delay, unijunction U4 is activated, thereby
providing a potential across resistor R51 to the base of transistor
Q8, turning on transistor Q8 and shutting down the system in a
manner as described with respect to unijunction U3 above.
Accordingly, when START SOL has been activated, causing the starter
motor to crank for the preselected period of time, timer U4 shuts
off the entire system to prevent excessively prolonged cranking of
the engine. Resistor R44 is connected between resistor R45 and
ground to drain capacitor C4, and thus reset the timing of
unijunction U4 at any time that the potential to capacitor C4 is
cut off prior to the full timing out of unijunction U4.
In a manner exactly analogous to that described immediately above,
prolonged activation, for more than ten seconds continuous
duration, of GAS SOL also will effect a shutdown of the system.
This protective arrangement is provided to prevent prolonged racing
of the engine should transistor Q14 short out and provide long
duration activation to GAS SOL. As previously described, activation
of transistor Q14 applies potential through diode D21 to activate
GAS SOL. This potential is also applied through diode D23 to
resistor R45, capacitor C4 and unijunction U4, thus providing for
the same ten second timing out of U4 as caused by prolonged
activation of START SOL. Therefore, as with START SOL, continuous
activation of GAS SOL for a period in excess of ten seconds will
effect shutdown of the system through timer U4 and transistor
Q8.
Provision also is made for shutting down the system immediately
upon any tampering with the vehicle, such as by the depression of
the brake pedal or the opening of the door of the vehicle. The
connectors labelled BRAKE and POS DOOR may be connected to the
brake light switch and the interior dome light of the vehicle
respectively, thus providing sources of positive potential when
activated, as by applying the brake, or by opening the door of a
vehicle having a positive ground. This potential is then applied
through either diode D26 or diode D27 to resistor R46 and then to
capacitor C4 and unijunction U4, the value of resistor R46 being
chosen to effect activation of U4 immediately and without the delay
associated with resistor R45. Accordingly, in a manner analogous to
that described immediately above with respect to excessively long
cranking by the starter motor, the application of this potential by
either depression of the brake pedal or the opening of the door
immediately shuts down the engine and deactivates the starting
system. Diode D25 provides for draining, through resistor R44, of
any charge remaining in capacitor C4 after unijunction U4 has been
activated through resistor R46. It may also be desired to shut down
and deactivate the system in response to the opening of the door of
a vehicle having a negative ground, as is the case in most
vehicles. In this case, the connector to a normally open grounding
switch, such as is associated with the interior dome light, is
denoted on the diagram as NEG DOOR and is connected through diode
D9 to a connection between resistors R18 and R19. When this switch
is closed, as by opening a door on the vehicle, the grounding of
resistor R18 deactivates transistors Q5 and Q11 and completely
deactivates the system and shuts down the engine.
Since it is assumed that this remote starting system will
frequently be used in a vehicle such as an automobile having a
manually operated key switch for manually energizing the ignition
system and operating the starter motor, additional protective
apparatus is incorporated to disable the energizing circuitry of
the starting system at any time such manually operated switch is
activated prior to the activation of the remote starting system.
When the engine is to be started through the manually operated
switch K3, without prior activation of the remote starting system,
the battery B+ potential will be applied to the STARTING B+ line
through switch K3, without the closing of relay K1 or the prior
energizing of the latching circuit Q11-Q5. Since the base of PNP
transistor Q15 is connected through resistor R49 to the STARTING B+
line, this application of potential to STARTING B+ through manually
operated switch K3 applies a potential to the base of transistor
Q15. The base of transistor Q15 is also connected through resistor
R50, zener diode Z2, diode D12 and resistor R30 to ground. Since
transistors Q11 and Q5 have not been activated in this case, there
is no potential at the cathode of diode D8 to prevent the grounding
of resistor R50 through zener Z2, diode D12 and resistor R30,
unlike the previously described situation in which the remote
starting system is activated first. Accordingly, when switch K3 is
closed, zener Z2 breaks down, and an appropriate bias is applied to
the base of transistor Q15, turning on that transistor and
providing a biasing path through its emitter-collector circuit from
STARTING B+ to resistor R52 and thence to the base of NPN
transistor Q8, turning on transistor Q8. Since the activation of
transistor Q8 provides an alternative grounding path independent of
the presence or absence of any potential at the cathode of diode
D8, transistors Q15 and Q8 comprise an additional latching circuit,
maintaining one another in the activated condition until
affirmatively turned off. It may be noted that another transient
and noise suppressing capacitor C7 is installed, with polarity
reversed, across the emitter and base of transistor Q15, in a
manner and for reasons similar to those discussed above with
respect to transistor Q11. By virtue of the latching circuit,
transistors Q15 and Q8 remain activated as long as switch K3 is
closed. As described above, the energizing circuit remains disabled
at any time Q8 is activated. Accordingly, the remote starting
system remains disabled as long as manually operated switch K3 is
closed.
When the starting system is activated first, it is prevented from
disabling itself in the above-described manner, upon the
energization of relay K1 by virtue of the brief delay between the
activation of the latching circuit Q11-Q5 and the closing of the
relay K1 contacts. Since solid state devices such as the
transistors Q11 and Q5 switch on with very little delay, on the
order of nanoseconds, and since a relay such as K1 closes much more
slowly, on the order of 15 milliseconds, activation of this
starting system by a control signal from the receiver energizes the
latching circuit Q11-Q5 and provides a positive potential at the
cathode of diode D8, which is connected to the cathode of
transistor Q11 and to diode D12, well before potential is applied
to the STARTING B+ line. Thus, the presence of B+ potential at the
cathode of diode D8 prevents the creation of a grounding path for
the base of transistor Q15 through resistor R50, zener Z2 and diode
D12. Accordingly, when the starting system is activated remotely,
without manual switch K3 being closed, transistor Q15 is not
activated and does not, itself, activated transistor Q8 to disable
the starting system.
To avoid overspeeding the engine once it has started, provision is
made in the system for disabling the user-controlled, selective
momentary fuel pumping apparatus after the engine has started. This
is achieved generally by grounding the collector of Q10 through R3
and transistor Q9. As previously described, once the engine is
started and running, the alternator output causes zener Z1 to break
down and to conduct the alternator output through diode D4. Since
resistor R1 is connected between the cathode of diode D4 and the
base of NPN transistor Q9, with resistor R2 connecting the base of
Q9 to ground, the alternator output also serves to turn on
transistor Q9. The emitter of Q9 is connected to ground, with the
collector connected to R3 and thence to the collector of transistor
Q10. Accordingly, activation of transistor Q9 effectively grounds
the collector of Q10 through resistor R3, the sole source of the
user-controlled fuel pumping signal, thus preventing activation of
Q7. As described above, activation of transistor Q7 is the means by
which the user commands selective momentary operation of GAS SOL.
Accordingly, the activation of transistor Q9 by the output of the
alternator prevents subsequent selective, user-controlled momentary
pumping of fuel into the engine by operation of the control signal
transmitter. As previously noted, stalling of the engine after
starting removes the alternator output, thus turning off transistor
Q9 and removing its grounding of the base of transistor Q7.
Accordingly, upon such stalling, the user may again remotely
command momentary pumping of fuel into the engine prior to its
restart.
An additional protective device is provided to prevent improper
activation of the momentary pumping apparatus by the starting
system when the engine is being operated under the control of the
manually operated switch K3. As previously described, starting of
the engine by means of switch K3 effects a latch between
transistors Q8 and Q15, locking out the starting operation of the
system. This latch establishes a grounding path from resistor R50
through diode D15 and transistor Q8. In addition to resistor R50,
resistor R48 is also connected to the anode of diode D15, with its
opposite contact connected to the base of transistor Q13. Resistor
R47 connects the base of Q13 to STARTING B+ line. Accordingly,
activation of transistor Q8, as by the latching of transistors Q15
and Q8, biases the base of transistor Q13, turning it on. Since the
emitter of transistor Q13 is connected to STARTING B+ line, and the
collector is connected to the base of transistor Q14, activation of
transistor Q13 provides the positive potential of STARTING B+ to
the base transistor Q14, thus reverse-biasing transistor Q14 and
preventing it from turning on regardless of any grounding path
established through resistor R42. Accordingly, at any time that
transistor Q15 has been activated, by the application of potential
to the STARTING B+ line prior to energization of the starting
system through transistors Q11 and Q5, GAS SOL is disabled, thereby
preventing improper system activation of the momentary fuel pumping
device.
The foregoing starting system has been described principally in
respect to its application to a spark ignition engine, such as may
be used in an automobile. However, the system is equally applicable
for use with numerous other types of combustion engines, including
diesel engines. If used in conjunction with a diesel engine having
a glow plug to assist in starting, it is desirable to preheat the
glow plug for a substantial period of time prior to the initiation
of the starting operation. A suitable modification to optimize this
system for application to a diesel engine might include the
connection of a relay controlling the glow plug to the IGNITION
plug connection associated with relay K1, so that the glow plug
will begin heating as soon as relay K1 is closed. Additionally, it
may be desirable to increase the delay associated with timer U1 to
provide for substantially longer preheating of the glow prior to
initiation of the starting operation. The starting system of this
invention provides for such adjustment of the timer U1 delay by a
simple modification of the previously described R-C circuit
comprising capacitor C1 and resistors R31, R32 and R33. The values
of these components are selected such that utilization of both R31
and R32 together provides a brief delay, such as five seconds,
while the elimination of the resistor R32 path from MAIN B+
provides a substantially longer delay, such as two minutes. Thus,
removal of the R32 path, such as by simply clipping the leads of
the resistor, provides for a longer delay to enable the flow plug
to preheat before activating the starting operation.
To adapt the starting system to certain engines in which the
alternator output is not suiable for signaling the starting of the
engine as described above, an alternative start sensing device may
be employed. Such a suitable alternative may be a pressure switch
connected to B+ and located in the intake manifold of the engine,
which switch closes in response to a predetermined level of
manifold pressure associated with the starting of the engine, thus
providing potential through the vacuum switch to diode D4. The
remaining portions of the starting system remain as described
above.
Numerous other additional features, such as disclosed in the
aforementioned U.S. Pat. Nos. 3,478,730, 3,685,606 and 3,793,529
may suitably be incorporated into this system to provide additional
functions and benefits. Accordingly, the scope of the invention is
not to be limited by the foregoing detailed description of a
preferred embodiment but is to be defined solely by the claims
appended hereto.
* * * * *