Electronic control device for transmission mechanism

Claim 2

Electronic device for controlling an automotive vehicle having an accelerator pedal, an engine throttle valve, at least one clutch, and a transmission mechanism having a plurality of stepped gear-ratios adapted for selection in operational sequence to effect a gear change in accordance with information about the speed of the vehicle and the load of the engine of said vehicle, said device comprising servocontrol members for said transmission mechanism, electric relAy means for actuating said servocontrol members, a generator of a general control voltage depending upon the speed and the position of the accelerator pedal of the vehicle, an apparatus for the automatic transmission of information signals, receiving at its input said general control voltage, and comprising a first group of (n-1) circuits in parallel for changing up to a higher gear ratio and a second group of (n-1) circuits in parallel for changing down to a lower gear ratio, n designating the number of forward speed gear ratios of the transmission mechanisms, these various gear change-up and change-down circuits comprising respective level detector stages adapted to trigger from a first state to a second state, and to thereby produce automatic control pulses when the control voltage exceeds selected thresholds whereat the respective gear changes are to take place, and which are arranged in stepped relation to one another according to the various gear ratios, first and second output stages having respective inputs connected to the various level detector stages comprised in said gear change-up circuits and in the said gear change-down circuits, and outputs connected to the electric relay means of the said servocontrol members, for converting the automatic control pulses emitted by the level detector stages, during their changes of state, into signal of calibrated duration, and for applying said signals to said electric relay means, and a manual control pulse selector, adapted to be hand operated by the driver for transmitting manual control pulses to the respective inputs of said first and second output stages in parallel with the automatic control pulses delivered by the various gear change-up and change-down circuits.

Claim 3

Control device according to claim 1 which comprises servocontrol members for operating said clutch, an output stage for the gear change-up pulses, a gear change-up control relay connected to said output stage and adapted to actuate a contact, and means controlling said clutch operating servocontrol members for differentiating the timing of the clutch reengagement when changing up to a higher gear from the timing provided when changing down to a lower gear, said means being connected to said contact.

Claim 4

Control device according to claim 1, in which said general control voltage generator comprises a tachometric generator delivering a voltage proportional to the vehicle speed, and in which a circuit connected in parallel to the terminals of said generator comprises an insulation diode in series with a resistor and a capacitor connected in parallel, a transistor, a second resistor connecting one terminal of said generator to the base of said last-named transistor and a potentiometer connected in the emitter-collector circuit of said transistor, the slide of said potentiometer being brought to the general control voltage and responsive to the accelerator pedal of the vehicle for causing said voltage to vary as a function of the engine torque.

Claim 5

Control device according to claim 1, wherein the said manual control pulse selector comprises a hand lever adapted to be set in two different positions corresponding to the one to automatic driving conditions and the other the manual driving conditions, and second and third contacts actuated by said hand lever for transmitting in each one of the positions of said hand lever, manual control pulses respectively to said first and second output stages.

Claim 6

Control device according to claim 4, which comprises a first AND gate, of which a first input is connected to the outputs of the said gear change-up circuits, a first OR circuit having a first input connected to the output of said first AND gate, a second input connected to the said second contact of the manual control pulse selector, and one output connected to the input of the said first output stage, a second AND gate, of which a first input is connected to the outputs of the said gear change-down circuits, a second OR circuit having one input connected to the output of said second AND gate, a second input connected to the said third contact of the manual control pulse selector, and an output connected to the input of said second output stage, the said manual control pulse selector comprising a fourth contact, connected in common to second inputs, respectively, of said first and second AND gates, said fourth contact transmitting a potential adapted to block said first and second AND gates when the nand lever of said manual control pulse selector is in the manual driving position.

Claim 7

Control device according to claim 5, in which said first and second AND gates comprise each a third input connected to the output of the general control voltage generator in order to block said first and second AND gates when said general control voltage is not present.

Claim 8

Control device according to claim 5, comprising means for signalling the engaged gear ratio of the transmission mechanism, said means comprising essentially a signalling line for each forward speed provided by said transmission mechanism, and an auxiliary or neutral line, for signalling the disengaged or neutral position of the transmission mechanism, only one of said signalling lines being brought to a predetermined voltage when the corresponding gear ratio is actually engaged, a rotary switch comprising contact studs to which are connected the said neutral line and the lines associated with the various gear ratios, respectively, a first movable contact arm adapted to engage each contact stud separately, a device for storing the predetermined voltage applied to said first movable contact arm of said rotary switch, and wherein each one of said gear change-up circuits comprises an input AND gate having a first input connected to the output of said general control voltage generator, a level detector stage, having means to adjust its trigger threshold and one input connected to the output of the input AND gate, a two-input output AND gate having its first input connected to the output of said level detector stage and the other input connected to the signalling line associated with the higher gear ratio of the two gear ratios between which the gear change-up circuit concerned is adapted to produce a gear change, a first capacitor connected to the output of each one of said output AND gates, and a third OR circuit having its inputs connected to the first capacitors of the various gear change-up circuits respectively and its output connected to the first input of the first AND gate.

Claim 9

Control device according to claim 7, which comprises a shaping and timing stage inserted in each signalling line and having its output connected to the second input of the output AND gate of the associated gear change-up circuit.

Claim 10

Control device according to claim 7 in which the input AND gate of each gear change-up circuit comprises a second input connected to the gear change-down circuit corresponding to the same pair of gear ratios of the transmission mechanism, and a second capacitor connected between said second input of said input AND gate and ground.

Claim 11

Control device according to claim 7, which comprises, between the output of the level detector stage of a gear change-up circuit associated with a given pair of gear ratios of the transmission mechanism, on the one hand, and the input of the gear change-down circuit associated with the same pair of gear ratios on the other hand, a third capacitor and a first resistor in parallel, and a diode connected in series therewith with a polarity in opposition to that of the general control voltage.

Claim 12

Control device according to claim 7, wherein each gear change-down circuit comprises a level detector stage having means to adjust its trigger threshold, means for attenuating the general control voltage and applying said attenuated voltage to the input of the said level detector stage, a first NOT gate having its input connected to the output of said level detector staGe, a checking AND gate having a first input connected to the output of said NOT gate and a second input connected to the output of the level detector stage of the gear change-up circuit corresponding to the same pair of gear ratios of the transmission mechanism, an output AND gate having a first input connected to the output of said checking AND gate, a second NOT gate having its input connected to the output of said checking AND gate and its output connected to the second input of said input AND gate of the gear change-up circuit associated with the same pair of gear ratios, and a fourth OR circuit having its inputs connected to the outputs of the output AND gates of the various gear change-down circuits, the output of said fourth OR circuit being connected to the first input of said second AND gate.

Claim 13

Control device according to claim 11, wherein each one of said gear change-up circuits comprises a level detector stage having a normal output and another complementary or reverse output, a timing monostable multivibrator having a predetermined trigger time and its input connected to the normal output of said level detector stage of said gear change-up circuit and the output connected to a third input of said output AND gate of said gear change-up circuit, a reversing transistor having its base connected to said complementary output of said level detector stage and the output electrode connected to the second input of said checking AND gate of said gear change-down circuit associated with the same pair of gear ratios of the transmission mechanism, said device further comprising a contact connected to a source of blocking potential and responsive to the accelerator pedal so as to be closed only in the fully released and raised position of said pedal, said contact being connected on the one hand to the bases of the reversing transistors of the various gear change-up circuits and on the other hand to the third inputs of said input AND gates of said last-named circuits.

Claim 14

Control device according to claim 11, wherein the output AND gate of said first gear change-down circuit associated with the gear change from second to first gear has two inputs connected the one to the output of the checking AND gate of said first change-down circuit, and the other to the said first signalling line for signalling the first gear position, the output AND gate of the second gear change-down circuit, associated with the change from third to second gear, having three inputs, of which the first one is connected to the output of said checking AND gate of said second gear change-down circuit and the second and third inputs are connected respectively, to said first and second signalling lines for signalling the first gear and second gear positions respectively, and the output AND gate of said third gear change-down circuit, associated with the change from fourth to third gear, has three inputs of which the first one is connected to the output of said checking AND gate of said third gear change-down circuit and the second and third inputs connected respectively to said second and third signalling lines for signalling the second and third gear positions respectively.

Claim 15

Control device according to claim 7, wherein the level detector stages of the various gear change-up and change-down circuits consist of Schmitt triggers, of which the voltage thresholds determining the triggering thereof in the change-up direction differ from the voltage thresholds for the change-down direction as a consequence of the hysterics effect inherent to said Schmitt triggers, said thresholds being so determined that the trigger voltage of a level detector stage of a gear change-down circuit associated with a given pair of gear ratios of the transmission mechanism, when said general control voltage decreases, is higher than the trigger voltage of a level detector stage of a gear change-up circuit associated with the same pair of gear ratios, when said general control voltAge decreases, and that the trigger voltage of a level detector stage of a gear change-down circuit associated with a given gear ratios of said transmission mechanism, when said general control voltage increases, is lower than the trigger voltage of the level detector stage of a gear change-up circuit associated with the same pair of gear ratios, when said general control voltage increases.

Claim 16

Control device according to claim 7, which comprises a safety circuit for preventing changing down resulting in an excessive engaging speed, this safety circuit being inserted between the third contact of said manual control pulse selector and the second OR circuit, said safety circuit comprising means for detecting the level of a voltage proportional to the vehicle speed and a logic circuit consisting of AND gates having connected to their inputs on the one hand the output of said voltage level detector means and on the other hand the signalling lines corresponding to all nonengaged lower gear ratios, the third contact of said manual control pulse selector being further connected to one of the inputs of each one of said AND gates gates.

Claim 17

A control device according to claim 15, in which the general control voltage generator comprises a tachometric generator delivering a voltage proportional to the vehicle speed, and said safety circuit comprises first, second, third and fourth level detector stages associated with the changes: first to neutral and neutral to reverse, second to first, third to second and fourth to third, respectively, said level detectors having stepped trigger thresholds and their inputs connected in common to said tachometric generator, and five AND gates associated with the changes: fourth to third, third to second, second to first, first to neutral and neutral to reverse, respectively, all of said AND gates having an input connected in common to the third contact of said manual control pulse selector, the first to neutral AND gate and the neutral to reverse AND gate having each another input connected to the input of the first level detector stage, the first to neutral AND gate having three other inputs connected respectively to the signalling lines which correspond respectively to the second, third and fourth forward speeds provided by said transmission mechanism, the second to first AND gate having a second input connected to the output of the second level detector stage and two other inputs connected respectively to the neutral signalling line and to the signalling line which corresponds to the first forward speed, the third to second AND gate having an input connected to the output of the third level detector stage and three other inputs connected respectively to the neutral signalling line and to the signalling lines which correspond respectively to said first and second forward speeds, and the fourth to third AND gate having an input connected to the output of the fourth level detector stage and four other inputs connected respectively to the neutral signalling line and 40 the signalling lines which correspond respectively to said first, second and third forward speeds, a fifth OR circuit having its inputs connected to the outputs of the five AND gates and its output connected to one input of the second OR circuit.

Claim 18

Control device according to claim 7 which comprises a safety circuit for preventing changing down resulting in excessive engine speed, this safety circuit comprising means for detecting the rotation speed of the vehicle engine and a trigger device adapted, when said engine speed exceeds a predetermined threshold, to block the second AND gate to inhibit the passage of automatic control pulses.

Claim 19

Control device according to claim 5, comprising a safety circuit for preventing automatic gear changing when the general control voltage is zero, said safety circuit being connected between third inputs of said first and second AND gates on the one hand, and the output of said general control voltage generAtor on the other hand, and said safety circuit comprising an input transistor and an output transistor both mounted with a common emitter, and a timing capacitor connected between the collector of the output transistor and ground.

Claim 20

Electronic device for controlling an automotive vehicle having an accelerator pedal, an engine throttle valve, at least one clutch, and a transmission mechanism having plurality of stepped gear-ratios, adapted for selection in operational sequence to effect a gear change, in accordance with information about the speed of the vehicle and the load of the engine of said vehicle, said device comprising servocontrol members for said transmission mechanism, electric relay means for actuating said servocontrol members, a generator of a general control voltage depending upon the speed and the position of the accelerator pedal of the vehicle, an apparatus for the automatic treatment of information signals, receiving at its input said general control voltage, and comprising a first group of n-1 circuits in parallel for changing up to a higher gear ratio and a second group of n-1 circuits in parallel for changing down to a lower gear ratio, n designating the number of forward speed gear ratios of the transmission mechanism, these various gear change-up and change-down circuits comprising respective level detector stages adapted to trigger from a first state to a second state, and to thereby produce automatic control pulses when the control voltage exceeds selected thresholds whereat the respective gear changes are to take place, and which are arranged in stepped relation to one another according to the various gear ratios, means for generating, when one of the n gear ratios of the transmission mechanism is engaged, one of n separate gear ratio indicating signals, corresponding respectively to said n gear ratios, first and second output stages having respective inputs, and outputs connected to the electric relay means of the said servocontrol members, means for transmitting an automatic control pulse produced by the level detector stage of any one of said circuits for changing from a first to a second gear ratio, to the input of one of said first and second output stages, only when the gear ratio indicating signal corresponding to said second gear ratio is not generated, and a manual control pulse selector, adapted to be hand operated by the driver for transmitting manual control pulses to the respective inputs of said first and second output stages in parallel with the automatic control pulses delivered by the various gear change-up and change-down circuits.

Claim 21

Electronic device for controlling an automotive vehicle having an accelerator pedal, an engine throttle valve, at least one clutch, and a transmission mechanism having plurality of stepped gear-ratios, adapted for selection in operational sequence to effect a gear change, in accordance with information about the speed of the vehicle and the load of the engine of said vehicle, said device comprising servocontrol members for said transmission mechanism, electric relay means for actuating said servocontrol members, a generator of a general control voltage depending upon the speed and the position of the accelerator pedal of the vehicle, an apparatus for the automatic treatment of information signals, receiving at its input said general control voltage, and comprising a first group of n-1 circuits in parallel for changing up to a higher gear ratio and a second group of n-1 circuits in parallel for changing down to a lower gear ratio, n designating the number of forward speed gear ratios of the transmission mechanism, these various gear change-up and change-down circuits comprising respective level detector stages adapted to trigger from a first state to a second state, and to thereby produce automatic control pulses when the control voltage exceeds selected thresholds whereat the respective gear changes are to take place, and which are arranged in stepped relation to one another according to the various gear ratios, means for generating, when one of the n gear ratios of the transmission mechanism is engaged, one of n separate gear ratio indicating signals, corresponding respectively to said n gear ratios, first and second output stages having respective inputs, and outputs connected to the electric relay means of the said servocontrol members, means for transmitting an automatic control pulse produced by the level detector stage of any one of said circuits for changing from a first to a second gear ratio, to the input of one of said first and second output stages, only when the gear ratio indicating signal corresponding to said second gear ratio is not generated, and a manual control pulse selector, adapted to be hand operated by the driver for transmitting manual control pulses to the respective inputs of said first and second output stages in parallel with the automatic control pulses delivered by the various gear change-up and change-down circuits.

Claim 22

Electronic device for controlling, an automotive vehicle having an accelerator pedal, an engine throttle valve, at least one clutch, and a transmission mechanism having a plurality of stepped gear-ratios, adapted for selection in operational sequence to effect a gear change, in accordance with information about the speed of the vehicle and the load of the engine of said vehicle, said device comprising servocontrol members for said transmission mechanism, electric relay means for actuating said servocontrol members, a generator of a general control voltage depending upon the speed and the position of the accelerator pedal of the vehicle, an apparatus for the automatic treatment of information signals, receiving at its input said general control voltage, and comprising a first group of n-1 circuits in parallel for changing up to a higher gear ratio and a second group of n-1 circuits in parallel for changing down to a lower gear ratio, n designating the number of forward speed gear ratios of the transmission mechanism, these various gear change-up and change-down circuits comprising respective level detector stages adapted to trigger from a first stage to a second state, and to thereby produce automatic control pulses, when the control voltage exceeds selected thresholds whereat the respective gear changes are to take place, and which are arranged in stepped relation to one another according to the various gear ratios, first and second output stages having respective inputs connected to the various level detector stages comprised in the said gear change-up circuits and in the said gear change-down circuits, and outputs connected to the electric relay means of the said servocontrol members, for converting the automatic control pulses emitted by the level detector stages, during their changes of state, into signals of calibrated duration, and for applying said signals to said electric relay means, a manual control pulse selector, adapted to be hand operated by the driver for producing manual control pulses, means for sensing the rotation speed of the vehicle engine, means for generating an inhibit signal when the sensed rotation speed exceeds at least one predetermined threshold, and means for transmitting a manual control pulse produced by said selector to the input of one of said first and second output stages, only when said inhibit signal is not generated.

Claim 23

Electronic device for controlling, an automotive vehicle having an accelerator pedal, an engine throttle valve, at least one clutch, and a transmission mechanism having a plurality of stepped gear-ratios, adapted for selection in operational sequence to effect a gear change, in accordance with information about the speed of the vehicle and the load of the engine of said vehicle, said device comprising servocontrol members for said transmission mechanism, electric relay means for actuating said servocontrol members, a generator of a general control voltage depending upon the speed and the position of the accelerator pedal of the vehicle, an apparatus for the automatic treatment of information signals, receiving at its input said general control voltage, and comprising a first group of n-1 circuits in parallel for changing up to a higher gear ratio and a second group of n-1 circuits in parallel for changing down to a lower gear ratio, n designating the number of forward speed gear ratios of the transmission mechanism, these various gear change-up and change-down circuits comprising respective level detector stages adapted to trigger from a first stage to a second state, and to thereby produce automatic control pulses, when the control voltage exceeds selected thresholds whereat the respective gear changes are to take place, and which are arranged in stepped relation to one another according to the various gear ratios, first and second output stages having respective inputs connected to the various level detector stages comprised in the said gear change-up circuits and in the said gear change-down circuits, and outputs connected to the electric relay means of the said servocontrol members, for converting the automatic control pulses emitted by the level detector stages, during their changes of state, into signals of calibrated duration, and for applying said signals to said electric relay means, a manual control pulse selector, adapted to be hand operated by the driver for producing manual control pulses, means for sensing the rotation speed of the vehicle engine, means for generating an inhibit signal when the sensed rotation speed exceeds at least one predetermined threshold, and means for transmitting a manual control pulse produced by said selector to the input of one of said first and second output stages, only when said inhibit signal is not generated.

Claim 24

Electronic device for controlling an automotive vehicle having an accelerator pedal, and engine throttle valve, at least one clutch, and a transmission mechanism having a plurality of stepped gear-ratios adapted for selection in operational sequence to effect a gear change in accordance with information about the speed of the vehicle and the load of the engine of said vehicle, said device comprising servocontrol members for said transmission mechanism, electric relay means for actuating said servocontrol members, a generator of a general control voltage depending upon the speed and the position of the accelerator pedal of the vehicle, an apparatus for the automatic treatment of information signals, receiving at its input said general control voltage, and comprising a first group of n-1 circuits in parallel for changing up to a higher gear ratio and a second group of -1 circuits in parallel for changing down to a lower gear ratio, n designating the number of forward speed gear ratios of the transmission mechanism, these various gear change-up and change-down circuits comprising respective level detector stages adapted to trigger from a first state to a second state, and to thereby produce automatic control pulses when the control voltage exceeds selected thresholds whereat the respective gear changes are to take place, and which are arranged in stepped relation to one another according to the various gear ratios, means for generating, when one of the n gear ratios of the transmission mechanism is engaged, one of n separate gear ratio indicating signals, corresponding respectively to said n gear ratios, first and second output stages having respective inputs, and outputs connected to the electric relay means of the said servocontrol members, means for transmitting an automatic control pulse produced by the level detector stage of any one of said circuits for changing from a first to a second gear ratio to the input of one of said first and second output stages, only when the gear ratio indicating signal corresponding to said second gear ratio is not generated, a manual control pulse selector for producing manual control pulses, means for sensing the rotation speed of the vehicle engine, means for generating n separate inhibit signals when the sensed rotation speed respectively exceeds n predetermined thresholds, corresponding respectively to changing from one of the n forward speed gear ratios down to the next lower gear ratio and means for transmitting a manual control pulse produced by said selector to the input of one of said first and second output stages, only when a gear ratio indicating signal, corresponding to one of said n gear ratios is generated and the inhibit signal corresponding to changing from said one gear-ratio down to the next lower gear ratio is not generated.

Claim 25

Electronic device for controlling an automotive vehicle having an accelerator pedal, and engine throttle valve, at least one clutch, and a transmission mechanism having a plurality of stepped gear-ratios adapted for selection in operational sequence to effect a gear change in accordance with information about the speed of the vehicle and the load of the engine of said vehicle, said device comprising servocontrol members for said transmission mechanism, electric relay means for actuating said servocontrol members, a generator of a general control voltage depending upon the speed and the position of the accelerator pedal of the vehicle, an apparatus for the automatic treatment of information signals, receiving at its input said general control voltage, and comprising a first group of n-1 circuits in parallel for changing up to a higher gear ratio and a second group of -1 circuits in parallel for changing down to a lower gear ratio, n designating the number of forward speed gear ratios of the transmission mechanism, these various gear change-up and change-down circuits comprising respective level detector stages adapted to trigger from a first state to a second state, and to thereby produce automatic control pulses when the control voltage exceeds selected thresholds whereat the respective gear changes are to take place, and which are arranged in stepped relation to one another according to the various gear ratios, means for generating, when one of the n gear ratios of the transmission mechanism is engaged, one of n separate gear ratio indicating signals, corresponding respectively to said n gear ratios, first and second output stages having respective inputs, and outputs connected to the electric relay means of the said servocontrol members, means for transmitting an automatic control pulse produced by the level detector stage of any one of said circuits for changing from a first to a second gear ratio to the input of one of said first and second output stages, only when the gear ratio indicating signal corresponding to said second gear ratio is not generated, a manual control pulse selector for producing manual control pulses, means for sensing the rotation speed of the vehicle engine, means for generating n separate inhibit signals when the sensed rotation speed respectively exceeds n predetermined thresholds, corresponding respectively to changing from one of the n forward speed gear ratios down to the next lower gear ratio and means for transmitting a manual control pulse produced by said selector to the input of one of said first and second output stages, only when a gear ratio indicating signal, corresponding to one of said n gear ratios is generated and the inhibit signal corresponding to changing from said one gear-ratio down to the next lower gear ratio is not generated.