Skid control system for vehicles

Claim 2

A control device for regulating the braking effect of a brake system of a vehicle with wheels on the basis of the wheel velocity and a set deceleration comprising, regulator means for establishing an indication corresponding to the set deceleration, circuit means forming a control signal corresponding to the velocity of the wheel to be controlled, network means responsive to an indication corresponding to the set deceleration and coupled to said circuit means for inhibiting changes in the value of the control signal formed by said circuit means at a rate greater than the indication, and electrical means responsive to the control signal for producing a brake modulation output when the change in the value of the signal is inhibited, said regulator means including variation means for varying the set deceleration as a function of the time during which the signal is not inhibited and during which the wheel velocity is simultaneously increasing.

Claim 3

A control as in claim 1, wherein said electrical means includes comparator means for comparing the value of the control signal to a second signal corresponding to the velocity of the wheel of the vehicle for forming a modulation signal when the value of the control signal departs from the value of the second signal.

Claim 4

A control device as in claim 2, wherein a second signal is formed by second circuit means responsive to the velocity of the wheel.

Claim 5

A control device as in claim 3, wherein said first-mentioned circuit means, said second circuit means and said network means form three arms of a bridge, said bridge having a fourth Arm.

Claim 6

A control device as in claim 4, wherein said current flow control device includes a transistor having an emitter collector path connected across said capacitor.

Claim 7

A control device as in claim 3, wherein said regulator means includes second energy storage means for establishing the set deceleration, and energy changing means responsive to the signal being inhibited or not inhibited for changing the energy while the signal is inhibited and the wheel velocity is simultaneously increasing.

Claim 8

A control device as in claim 3, wherein the regulator means includes second energy storage means coupled to the energy flow control means for changing the energy flow, second and third energy flow control means coupled to said second storage means, said second flow control means changing the flow of energy in one direction when the signal is not inhibited and the wheel velocity increasing, said third flow control means changing the flow in the other direction when the signal is not inhibited and the wheel velocity is decreasing.

Claim 9

A control device as in claim 7, wherein said second energy storage means includes a capacitor and said energy flow control means each includes amplifier means connected across the capacitor and responsive to said circuit means.

Claim 10

A control device as in claim 2, wherein said network means includes energy storage means responsive to the control signal of said circuit means and energy flow control means coupled to said regulator means for regulating the rate of change of energy of said storage means.

Claim 11

A control device as in claim 2, wherein said network means includes a capacitor responsive to the control signal of said circuit means and a current-flow device responsive to the indication of said regulator means for controlling the rate of discharge of said device.

Claim 12

A control device for varying a pressure modulator to reduce the pressure of brake fluid in a skid control system when the wheel velocity drops below the speed established by a preset deceleration, comprising first and second transistors having respective bases each connected to a voltage corresponding to the wheel velocity to be regulated, a load circuit connected in series with the emitter collector circuit of the first transistor, a capacitor connected in series with the emitter base circuit of the second transistor, a discharging transistor connected in parallel with said capacitor, a base in said transistor for receiving a voltage conforming to the preset deceleration to be applied, electric means for producing a signal to the pressure modulator to reduce the pressure of braking fluid when the voltage across said capacitor exceeds the voltage across the load circuit, and regulator means responsive to a voltage corresponding to the wheel velocity and to the capacitor voltage for reducing the preset deceleration when the wheel velocity voltage exceeds the voltage across the capacitor and the wheel velocity is increasing and for increasing the deceleration when the wheel velocity voltage exceeds the voltage across the capacitor and the wheel velocity is decreasing.

Claim 13

A control device for varying a pressure modulator to reduce the pressure of brake fluid in a skid control system when the wheel velocity drops below the speed established by a preset deceleration, comprising first and second transistors having respective bases each connected to a voltage corresponding to the wheel velocity to be regulated, a load circuit connected in series with the emitter collector circuit of the first transistor, a capacitor connected in series with the emitter base circuit of the second transistor, a discharging transistor connected in parallel with said capacitor, a base in said transistor for receiving a voltage conforming to the preset deceleration to be applied, electric means for producing a signal to the pressure modulator to reduce the pressure of braking fluid when the voltage across said capacitor exceeds the voltage across the load circuit, and regulator means responsive to a voltage corresponding to the wheel velocity and to the capacitor voltage for reducing the preset deceleration when the wheel velocity voltage exceeds the voltage across the capacitor and the wheel velocity is increasing and for increasing the deceleration when the wheel velocity voltage exceeds the voltage across the capacitor and the wheel velocity is decreasing.

Claim 14

A control device as in claim 11, wherein said load circuit comprises a third transistor having a base connected to the base of said discharge transistor.

Claim 15

A skid control system for the braking arrangement of a vehicle having wheels comprising control means for modulating the braking effect of the braking arrangement, sensing means for sensing the velocity of a wheel of the vehicle, regulator means for establishing an indication corresponding to a given limit of deceleration, circuit means responsive to said sensing means for forming a control signal corresponding to the velocity sensed, network means responsive to said regulator means and coupled to said circuit means for inhibiting changes in the value of the signal formed by said circuit means at a rate greater than the indication, and electrical means responsive to the control signal and connected to said control means fOr effecting modulation when the change in the value of the signal is inhibited, said regulator means including variation means for varying the set deceleration as a function of the time during which the signal is not inhibited and during which the wheel velocity is simultaneously increasing.

Claim 16

A skid control system for the braking arrangement of a vehicle having wheels comprising control means for modulating the braking effect of the braking arrangement, sensing means for sensing the velocity of a wheel of the vehicle, regulator means for establishing an indication corresponding to a given limit of deceleration, circuit means responsive to said sensing means for forming a control signal corresponding to the velocity sensed, network means responsive to said regulator means and coupled to said circuit means for inhibiting changes in the value of the signal formed by said circuit means at a rate greater than the indication, and electrical means responsive to the control signal and connected to said control means fOr effecting modulation when the change in the value of the signal is inhibited, said regulator means including variation means for varying the set deceleration as a function of the time during which the signal is not inhibited and during which the wheel velocity is simultaneously increasing.

Claim 17

A skid control system as in claim 13, wherein said electrical means includes comparator means for comparing the value of the control signal to a second signal corresponding to the velocity of the wheel of the vehicle for forming a modulation signal when the value of the control signal departs from the value of the second signal.

Claim 18

A skid control system as in claim 13, wherein said network means including energy storage means responsive to the control signal of said circuit means, and energy flow control means coupled to said regulator means for regulating the rate of change of energy of said energy storage means.

Claim 19

A skid control system as in claim 14, wherein a second signal is formed by second circuit means responsive to said sensing means.

Claim 20

A skid control system as in claim 13, wherein said network means includes a capacitor responsive to the control signal of said circuit means, and a current flow control device responsive to the indication of said regulator means for controlling the rate of discharge of said device.

Claim 21

A skid control system as in claim 17, wherein said current flow control device includes a current amplifier.

Claim 22

A skid control system as in claim 17, wherein said amplifier includes a transistor having a main path of current flow connected across said capacitor.

Claim 23

A skid control system for the braking arrangement of a vehicle having wheels comprising control means for modulating the braking effect of the braking arrangement, sensing means for sensing the velocity of a wheel of the vehicle, regulator means for establishing an indication corresponding to a given limit of deceleration, circuit means responsive to said sensing means for forming a control signal corresponding to the velocity sensed, network means responsive to said regulator means and coupled to said circuit means for inhibiting changes in the value of the signal formed by said circuit means at a rate greater than the indication, and electrical means responsive to the control signal and connected to said control means for effecting modulation when the change in the value of the signal is inhibited said network means including energy storage means responsive to the control signal of said circuit means, and energy flow control means coupled to said regulator means for regulating the rate of change of energy of said energy storage means the second signal being formed by second circuit means responsive to the sensing means; said first-mentioned circuit means, said second circuit means and said network means forming three arms of a bridge, said bridge having a fourth arm.

Claim 24

A skid control system for the braking arrangement of a vehicle having wheels comprising control means for modulating the braking effect of the braking arrangement, sensing means for sensing the velocity of a wheel of the vehicle, regulator means for establishing an indication corresponding to a given limit of deceleration, circuit means responsive to said sensing means for forming a control signal corresponding to the velocity sensed, network means responsive to said regulator means and coupled to said circuit means for inhibiting changes in the value of the signal formed by said circuit means at a rate greater than the indication, and electrical means responsive to the control signal and connected to said control means for effecting modulation when the change in the value of the signal is inhibited said network means including energy storage means responsive to the control signal of said circuit means, and energy flow control means coupled to said regulator means for regulating the rate of change of energy of said energy storage means the second signal being formed by second circuit means responsive to the sensing means; said first-mentioned circuit means, said second circuit means and said network means forming three arms of a bridge, said bridge having a fourth arm.

Claim 25

A skid control system as in claim 20, wherein said comparator means includes a differential amplifier.

Claim 26

A skid control system for a vehicle having a wheel and a brake system for slowing the wheel, comprising wheel velocity detecting means coupled to the wheel, control means responsive to said detecting means for initiating a signal when the wheel velocity decreases faster than a given rate of decrease and for maintaining the signal while the velocity is less than a velocity corresponding to the given rate of decrease, brake modulating means coupled to said control means for decreasing the braking effectiveness of the system on the wheel in response to the signal and reversing the decrease in the absence of the signal, said control means having velocity-change responsive means coupled to said detecting means for producing a first indication in response to increases in the wheel velocity during absence of the signal and a second indication in response to decrease in the wheel velocity during the absence of the signal, and setting means responsive to said control means for reducing tHe given rate of decrease in response to the first indication and increasing the given rate of decrease in response to the second indication.

Claim 27

A skid control system for a vehicle having a wheel and a brake system for slowing the wheel, comprising wheel velocity detecting means coupled to the wheel, control means responsive to said detecting means for initiating a signal when the wheel velocity decreases faster than a given rate of decrease and for maintaining the signal while the velocity is less than a velocity corresponding to the given rate of decrease, brake modulating means coupled to said control means for decreasing the braking effectiveness of the system on the wheel in response to the signal and reversing the decrease in the absence of the signal, said control means having velocity-change responsive means coupled to said detecting means for producing a first indication in response to increases in the wheel velocity during absence of the signal and a second indication in response to decrease in the wheel velocity during the absence of the signal, and setting means responsive to said control means for reducing tHe given rate of decrease in response to the first indication and increasing the given rate of decrease in response to the second indication.

Claim 28

A system as in claim 22, wherein said setting means includes energy storage means, first changing means for changing the energy level in said energy storage means in one direction during the first indication and second changing means for changing the energy level in said energy storage means in the other direction during the second indication.

Claim 29

A system as in claim 23, wherein said energy storage means includes a capacitor.

Claim 30

A system as in claim 24, wherein said first changing means includes circuit means for charging the capacitor, and wherein said second changing means includes circuit means for discharging the capacitor.

Claim 31

A system as in claim 25, wherein said control means include second energy storage means, first energy flow means responsive to said detecting means for changing the level of energy in said second energy storage means in one direction during the absence of current and second energy flow means responsive to said detecting means for changing the level of energy in said energy storage means in the other direction during the presence of the signal.

Claim 32

A system as in claim 26, wherein said second energy storage means includes a capacitor and said first and second energy flow means include charging and discharging circuits.

Claim 33

A system as in claim 27, wherein said charging circuit applies a voltage across the capacitor in said second energy storage means corresponding to the wheel velocity and wherein said discharge circuit discharges said capacitor in said second energy storage means at a rate corresponding to the voltage of said first capacitor means.

Claim 34

A system as in claim 28, wherein said control means further comprise comparator means responsive to said detecting means for comparing the level of the wheel velocity as compared to the level of the charge on said capacitor in said second energy storage means.

Claim 35

A system as in claim 29, wherein said charging and discharging circuits in said capacitor and said first energy storage means form means for producing an output signal when the level of the wheel velocity drops at a greater rate than the discharging circuit is capable of discharging the capacitor in said second energy storage means.

Claim 36

A system as in claim 30, wherein said charging means in said first changing means reduces the given rate of decrease in response to said first indication.

Claim 37

A system as in claim 31, wherein said discharging means in said second changing means discharges said capacitor in said first energy storage means during the second indication.

Claim 38

A system as in claim 32, wherein said discharging means includes a transistor responsive to one of the indications.

Claim 39

A system as in claim 32, wherein said setting means includes connection means connecting the charging circuit for said capacitor in said second energy storage means to said brake modulating means for extending the signal during the first indication.

Claim 40

A system as in claim 32, wherein the discharge circuit for said capacitor in said first energy storage means includes a resistor connected across said capacitor.

Claim 41

A system as in claim 35, wherein said means for applying the additional indication includes a transistor responsive to the first indication.

Claim 42

A system as in claim 32, wherein said control means include means responsive to the first indication for applying an additional signal to said pressure modulator means during the first indication.

Claim 43

A system as in claim 37, wherein said means for applying the additional indication includes a transistor responsive to the first indication.

Claim 44

A system as in claim 38, wherein said brake modulating means includes a valve for decreasing the fluid pressure in response to the signal.

Claim 45

A device as in claim 38, wherein said brake modulating means includes a valve for reducing the pressure in response to the signal and a retaining valve responsive to the additional signal for reducing the pressure of the brake fluid.

Claim 46

A system as in claim 23, wherein said control means include second energy storage means, energy flow means responsive to said detecting means for changing the level of energy in said second energy storage means in one direction during the absence of the signal and second energy flow means responsive to said detecting means for changing the level of energy storage in said second energy storage means in the other direction during the presence of the signal.

Claim 47

A system as in claim 41, wherein said first energy storage means includes a capacitor.

Claim 48

A system as in claim 42, wherein said second energy storage means includes a capacitor.