Automatic shift control system for automatic transmission

Claim 2

In an automatic transmission for an engine-driven vehicle having a torque converter coupled to a gear unit having gears and frictionally engaging means for accomplishing the selective meshing engagement of said gears in said gear unit, an automatic shift control system comprising: a hydraulic actuating circuit means including a manual fluid valve having a first position for establishing a relatively high forward driving ratio and a second position for establishing a relatively low forward driving ratio and shift valve means disposed in fluid communication passages between said manual valve and said frictionally engaging means for selectively actuating said frictionally engaging means; electrical signal generating means connected to said vehicle and including at least one signal generator for generating an electrical output signal representing at least one shift determining type of vehicle operating condition; electrical shift point computing means coupled between said generating means and shift valve means for automatically computing shift point signals representing an automatic shifting pattern for actuating said shift valve means as a function of the Output of said signal generating means; and control means for varying said automatic shifting pattern thereby varying the shift point even though said manual fluid valve is maintained in said first position whereby a suitable shift point may be manually selected as desired depending on the varying driving conditions of the vehicle.

Claim 3

In an automatic transmission for an engine-driven vehicle having an engine throttle, said transmission being of the kind having an output shaft and a torque converter coupled to a gear unit containing gears for driving said shaft and having frictionally engaging means for accomplishing the selective meshing engagement of the gears in said gear unit, an automatic shift control system comprising: a hydraulic actuating circuit including a manual shift region setting valve and a distributing valve for distributing fluid under pressure to said frictionally engaging means for controlling said frictionally engaging means, first means connected to said throttle for generating a first signal responsive to the engine throttle position, second means connected to said transmission output shaft for generating a second signal responsive to the r.p.m. of the output shaft of said transmission, a plurality of discriminating circuit means connected to said first and second means for generating an output signal when the relation between said first and second signals satisfies a predetermined condition, switch means connected with at least one of said discriminating circuits for permitting or interrupting the delivery of the output signal from said discriminating circuit, and OR circuit means coupled to said discriminating circuits for generating an electrical output signal for triggering actuation of said frictionally engaging means when at least one of the signals from said discriminating circuits is applied thereto directly or through said switch means.

Claim 4

In an automatic transmission for an engine-driven vehicle having an engine throttle, said transmission being of the kind having an output shaft and a torque converter coupled to a gear unit containing gears for driving said shaft and having frictionally engaging means for accomplishing the selective meshing engagement of the gears in said gear unit, an automatic shift control system comprising: a hydraulic actuating circuit including a manual shift region setting valve and a distributing valve for distributing fluid under pressure to said frictionally engaging means for controlling said frictionally engaging means, first means connected to said throttle for generating a first signal responsive to the engine throttle position, second means connected to said transmission output shaft for generating a second signal responsive to the r.p.m. of the output shaft of said transmission, a plurality of discriminating circuit means connected to said first and second means for generating an output signal when the relation between said first and second signals satisfies a predetermined condition, switch means connected with at least one of said discriminating circuits for permitting or interrupting the delivery of the output signal from said discriminating circuit, and OR circuit means coupled to said discriminating circuits for generating an electrical output signal for triggering actuation of said frictionally engaging means when at least one of the signals from said discriminating circuits is applied thereto directly or through said switch means.

Claim 5

In a shift control system for a vehicle transmission which includes a transmission gear assembly, engaging means coupled to said assembly for effecting gear shifting engagement of said transmission gear assembly, and shifting means coupled to said engaging means for operating said engaging means, the improvement comprising: electrical signal generator means connected to said vehicle for producing electrical output signals representative of shift determining operating conditions of the vehicle, computing circuit means connected to the output of said signal generator means for acting upon the output signals therefrom to establish a shift condition, means connected to the output of said computing circuit means for actuating said shifting means, a shift condition modification circuit connected between said computing circuit means and said actuating means for varying said shift condition when said modification circuit is energized and means coupled to said shift condition modification circuit for manually affecting energization thereof.

Claim 6

In a shift control system for a vehicle transmission which includes a transmission gear assembly, engaging means coupled to said assembly for effecting gear shifting engagement of said transmission gear assembly, and shifting means coupled to said engaging means for operating said engaging means, the improvement comprising: electrical signal generator means connected to said vehicle for producing electrical output signals representative of shift determining operating conditions of the vehicle, computing circuit means connected to the output of said signal generator means for acting upon the output signals therefrom to establish a shift condition, means connected to the output of said computing circuit means for actuating said shifting means, a shift condition modification circuit connected between said computing circuit means and said actuating means for varying said shift condition when said modification circuit is energized and means coupled to said shift condition modification circuit for manually affecting energization thereof.

Claim 7

The shift control system of claim 3 wherein said signal generating means comprises a toothed disc of magnetic material securely mounted coaxially on the output shaft of said vehicle transmission and a coil located adjacent to the outer periphery of said toothed disc the axis of said coil being located on a line radial to said disc whereby a voltage having a frequency proportional to the rotational speed of said output shaft is induced in said coil.

Claim 8

The shift control system of claim 4 further including a digital to analog converter electrically connected between said coil and said establishing circuit.

Claim 9

The shift control system of claim 3 wherein said signal generating means comprises a movable contact mechanically connected with the carburetor throttle of said vehicle, a plurality of fixed contacts arranged to engage with said movable contact, each of said fixed contacts being connected through a separate resistance to a source of electrical power, and a voltage tap line connected in common between said resistances and said power source wherein the movement of said carburetor throttle causes said movable contact to engage a varying number of fixed contacts and thus to vary the output voltage on said voltage tap line proportional to the setting of said carburetor throttle.

Claim 10

The shift control system of claim 3 wherein said signal generating means comprises a toothed disc of magnetic material securely mounted coaxially on the output shaft of said vehicle transmission and a coil located adjacent to the outer periphery of said toothed disc the axis of said coil being located on a line radial to said disc whereby a voltage having a frequency proportional to the rotational speed of said output shaft is induced in said coil, and a movable contact mechanically connected with the carburetor throttle of said vehicle, a plurality of fixed contacts arranged to engage with said movable contact each of said fixed contacts connected through a separate resistance to a source of electrical power and a voltage tap line connected in common between said resistances and said power source wherein the movement of the carburetor throttle causes said movable contact to engage a varying number of said contacts and thus to vary the output voltage on said voltage tap line proportional to the carburetor throttle setting.

Claim 11

The shift control system of claim 3 wherein said shifting means comprises a source of pressurized liquid and a hydraulic system having at least one valve for controlling the flow of liquid within said hydraulic system and at least one hydraulic operator in liquid connection with said hydraulic system and in mechanical connection with said engaging means for operating said engaging means.

Claim 12

The shift control system of claim 8 wherein said engaging means comprises at least one clutch and said hydraulic operator comprises a servo chamber mechanically adapted to cause the engagement of said clutch.

Claim 13

The shift control system of claim 8 wherein said engaging means comprises at least one brake band and said hydraulic operator comprises a servo chamber mechanically adapted to cause the engagement of said brake band.

Claim 14

The shift control system of claim 3 wherein said signal generating means produces two signals and said establishing circuit comprises a comparator having first and second input leads and an output lead, one of said two signals being applied to said first input lead and the other of said two signals being applied to said first input lead, said comparator producing an output on said output lead only when said first signal exceeds said second signal.

Claim 15

The shift control system of claim 11 further including a feedback circuit connected between said output lead of said comparator and said first input lead thereof for adding a portion of the output signal produced by said comparator to the input signal at said first input lead whereby signals on said output lead are stabilized.

Claim 16

The shift control system of claim 12 wherein said shift modification circuit comprises a second comparator which is electrically identical to the first comparator and has electrically identical input and output leads but differs from said first comparator in that a reference signal is applied to the second input lead of said second comparator whereby said second comparator produces a different output from said first comparator and an electrical ''''or'''' gate to which the output leads of said first and second comparators are connected as inputs and from which an output lead extends which is connected to said actuating means and means causing said ''''or'''' gate to connect either said first or said second comparator to said actuating means.

Claim 17

The shift control system of claim 13 wherein the means for energizing said shift condition modification circuit comprises a switch connected between said second comparator and said ''''or'''' gate.

Claim 18

In an automatic transmission for an engine-driven vehicle having a torque converter coupled to a gear unit having geArs and frictionally engaging means for accomplishing the selective meshing engagement of gears in said gear unit to effect shifting between various gear ratios, an automatic shift control system comprising: hydraulic actuating means including a manually controlled fluid valve connected to said frictionally engaging means for selectively actuating said frictionally engaging means to effect said shifting in response to supplied electrical shift point signals, electrical signal generating means connected to said vehicle for being responsive to at least one gear shift determining type of vehicle operating conditions for supplying electrical output signals representative thereof, computing means connected between said signal generating means and said hydraulic actuating means for automatically computing and supplying as an output a first set of electrical shift point signals as a first function of said vehicle operating conditions corresponding to a first shift pattern suitable for a first driving environment, further means connected to said computing means for effecting a change in the output thereof to a second set of electrical shift point signals as a second function of said vehicle operating conditions corresponding to a second shift pattern suitable for a second driving environment, and manual switch means for manually activating said further means independently of said manually controlled fluid valve whereby a driver of said vehicle may manually change the system operation, from said first shift pattern to said second shift pattern upon detecting a change from said first to said second driving environment.

Claim 19

In an automatic transmission for an engine-driven vehicle having a torque converter coupled to a gear unit having geArs and frictionally engaging means for accomplishing the selective meshing engagement of gears in said gear unit to effect shifting between various gear ratios, an automatic shift control system comprising: hydraulic actuating means including a manually controlled fluid valve connected to said frictionally engaging means for selectively actuating said frictionally engaging means to effect said shifting in response to supplied electrical shift point signals, electrical signal generating means connected to said vehicle for being responsive to at least one gear shift determining type of vehicle operating conditions for supplying electrical output signals representative thereof, computing means connected between said signal generating means and said hydraulic actuating means for automatically computing and supplying as an output a first set of electrical shift point signals as a first function of said vehicle operating conditions corresponding to a first shift pattern suitable for a first driving environment, further means connected to said computing means for effecting a change in the output thereof to a second set of electrical shift point signals as a second function of said vehicle operating conditions corresponding to a second shift pattern suitable for a second driving environment, and manual switch means for manually activating said further means independently of said manually controlled fluid valve whereby a driver of said vehicle may manually change the system operation, from said first shift pattern to said second shift pattern upon detecting a change from said first to said second driving environment.

Claim 20

An automatic shift control system as in claim 15 wherein said hydraulic actuating means includes electrically operated solenoid valves which are spring biased to an up-shifted position so that no electrical operating power is required during high gear operation.

Claim 21

An automatic shift control system as in claim 16 wherein said manually controlled fluid valve effects completely manual control over said shifting between various gear ratios when said electrically operated solenoid valves are in their spring biased positions.

Claim 22

An automatic shift control system as in claim 15 wherein: said further means comprises a second computing means connected to said signal generating means for automatically supplying second output signals as a function of at least one of said shift determining vehicle operating conditions and an OR circuit connected to both of said computing means for effectively combining said first set of electrical shift point signals with said second output signals to produce said second set of electrical shift point signals, and said manual switch means is connected to the output of said second computing means for effectively disconnecting said second output signals from said OR circuit in response to manual actuation by a driver of the vehicle.