Antiskid brake control system

Claim 2

An antiskid brake control system comprising: a brake circuit for given wheels of a motor vehicle, said brake circuit including therein a brake pressure control means; a deceleration sensing means coupled to at least one of said given wheels to generate a rotational deceleration signal; and an electronic circuit means coupled to said sensing means and said control means to provide a first signal combination to control said control means to decrease the brake pressure in said brake circuit, a second signal combination following said first signal combination to control said control means to maintain constant the decreased brake pressure in said brake circuit and a third signal combination following said second signal combination to control said control means to return said brake circuit to its normal operation; each of said first, second and third signal combinations including a plurality of signals, each signal of said plurality of signals having a different characteristic derived from said deceleration signal; said second signal combination including a first signal indicating when said deceleration signal equals zero, and a second signal equal to a positive differential coefficient of said deceleration signal.

Claim 3

A sysem according to claim 1, wherein said first signal combination includes a first signal indicating that said deceleration signal has achieved at least a given value, and a second signal indicating that a predetermined speed change has occurred after said deceleration signal has achieved said given value.

Claim 4

A system according to claim 1, wherein said first signal combination includes a first signal indicating that said deceleration signal has achieved at least a given value, and a second signal which is a predetermined integrated value of said deceleration signal after said deceleration signal has achieved said given value.

Claim 5

An antiskid brake control system comprising: a brake circuit for given wheels of a motor vehicle, said brake circuit including therein a brake pressure control means; a deceleration sensing means coupled to at least one of said given wheels to generate a rotational deceleration signal; and an electronic circuit means coupled to said sensing means and said control means to provide a first signal combination to control said control means to decrease the brake pressure in said brake circuit, a second signal combination following said first signal combination to control said control means to maintain constant the decreased brake pressure in said brake circuit and a third signal combination following said second signal combination to control said control means to return said brake circuit to its normal operation; each of said first, second and third signal combinations including a plurality of signals, each signal of said plurality of signals having a different characteristic derived from said deceleration signal; said third signal combination including a first signal indicating when said deceleration signal equals zero, and a second signal equal to a negative differential coefficient of said deceleration signal.

Claim 6

An antiskid brake control system comprising: a brake circuit for given wheels of a motor vehicle, said brake circuit including therein a brake pressure control means; a deceleration sensing means coupled to at least one of said given wheels to generate a rotational deceleration signal; and an electronic circuit means coupled to said sensing means and said control means to provide a first signal combination to control said control means to decrease the brake pressure in said brake circuit, a second signal combination following said first signal combination to control said control means to maintain constant the decreased brake pressure in said brake circuit and a third signal combination following said second signal combination to control said control means to return said brake circuit to its normal operation; each of said first, second and third signal combinations including a plurality of signals, each signal of said plurality of signals having a different characteristic derived from said deceleration signal; said third signal combination including a first signal indicating when said deceleration signal equals zero, and a second signal equal to a negative differential coefficient of said deceleration signal.

Claim 7

An antiskid brake control system comprising: a brake circuit for given wheels of a motor vehicle, said brake circuit including therein a brake pressure control means; a deceleration sensing means coupled to at least one of said given wheels to generate a rotational deceleration signal; and an electronic circuit means coupled to said sensing means and said control means to provide a first signal combination to control said control means to decrease the brake pressure in said brake circuit, a second signal combination following said first signal combination to control said control means to maintain constant the decreased brake pressure in said brake circuit and a third signal combination following said second signal combination to control said control means to return said brake circuit to its normal operation; each of said first, second and third signal combinations including a plurality of signals, each of said plurality of signals having a different characteristic derived from said deceleration signal; said first signal combination including a first signal indicating that said deceleration signal has achieved at least a given value, and a second signal indicating that a predetermined speed change has occured after said deceleration signal has achieved said given value; said second signal combination including a third signal indicating when said deceleration signal equals zero, and a fourth signal equal to a positive differential coefficient of said deceleration signal; and said third signal combination including said third signal, and a fifth signal equal to a negative differential coefficient of said deceleration signal.

Claim 8

An antiskid brake control system comprising: a brake circuit for given wheels of a motor vehicle, said brake circuit including therein a brake pressure control means; a deceleration sensing means coupled to at least one of said given wheels to generate a rotational deceleration signal; and an electronic circuit means coupled to said sensing means and said control means to provide a first signal combination to control said control means to decrease the brake pressure in said brake circuit, a second signal combination following said first signal combination to control said control means to maintain constant the decreased brake pressure in said brake circuit and a third signal combination following said second signal combination to control said control means to return said brake circuit to its normal operation; each of said first, second and third signal combinations including a plurality of signals, each of said plurality of signals having a different characteristic derived from said deceleration signal; said first signal combination including a first signal indicating that said deceleration signal has achieved at least a given value, and a second signal indicating that a predetermined speed change has occured after said deceleration signal has achieved said given value; said second signal combination including a third signal indicating when said deceleration signal equals zero, and a fourth signal equal to a positive differential coefficient of said deceleration signal; and said third signal combination including said third signal, and a fifth signal equal to a negative differential coefficient of said deceleration signal.

Claim 9

A system according to claim 5, wherein said brake circuit includes a first pressure medium line connected between the output of a master cylinder and a wheel brake cylinder associated with said one of said given wheels and, a second pressure medium line connected between said wheel brake cylinder and a pressure medium reservoir; and said control means includes a normally open input valve connected in said first line, and a normally closed output valve connected in said second line, said first signal combination actuating said input valve from its normally open condition to a closed condition and actuating said output valve from its normally closed condition to an open condition, said second signal combination actuating said output valve to return to its normally closed condition, and said third signal combination actuating said input valve to return to its normally open condition.

Claim 10

A system according to claim 6, wherein said electronic circuit means includes an integrator coupled to said sensing means having a threshold level equal to said given valve to produce said second signal, a first AND gate coupled to said sensing means and said integrator to produce said first signal combination, first and second bistable devices each of said bistable devices having two inputs, the output of one of said first and second bistable devices being coupled to said input valve for controlling the condition thereof and the output of the other of said first and second bistable devices being coupled to said output valve for controlling the condition thereof, one input of each of said first and second bistable devices being coupled to said first AND gate to set each of said first and second bistable devices to actuate said input valve to its closed condition and to actuate said output valve to its open condition, an inverter coupled to said sensing means to produce said third signal, a differentiator coupled to said sensing means, a positive polarity detector coupled to said differentiator to produce said fourth signal, a negative polarity detector coupled to said differentiator to produce said fifth signal, a second AND gate coupled to said inverter and said positive polarity detector to produce said second signal combination for coupling to the other input of said other of said bistable devices for reset thereof to actuate said output valve to its closed condition, and a third AND gate coupled to said inverter and said negative polarity detector to produce said third signal combination for coupling to the other input of said one of said bistable devices for reset thereof to actuate said input valve to its open condition.

Claim 11

An antiskid brake control system comprising: a brake circuit for given wheels of a motor vehicle, said brake circuit including therein a brake pressure control means; a deceleration sensing means coupled to at least one of said given wheels to generate a rotational deceleration signal; and an electronic circuit means coupled to said sensing means and said control means to provide a first signal combination to control said control means to decrease the brake pressure in said brake circuit, a second signal combination following said first signal combination to control said control means to maintain constant the decreased brake pressure in said brake circuit and a third signal combination following said second signal combination to control said control means to return said brake circuit to its normal operation; each of said first, second and third signal combinations including a plurality of Signals, each signal of said plurality of signals having a different characteristic derived from said deceleration signal; said first signal combination including a first signal indicating that said deceleration signal has achieved at least a given value, and a second signal which is a predetermined integrated value of said deceleration signal after said deceleration signal has achieved said given value; said second signal combination including a third signal indicating when said deceleration signal equals zero, and a fourth signal equal to a positive differential coefficient of said deceleration signal; and said third signal combination including said third signal, and a fifth signal equal to a negative differential coefficient of said deceleration signal.

Claim 12

An antiskid brake control system comprising: a brake circuit for given wheels of a motor vehicle, said brake circuit including therein a brake pressure control means; a deceleration sensing means coupled to at least one of said given wheels to generate a rotational deceleration signal; and an electronic circuit means coupled to said sensing means and said control means to provide a first signal combination to control said control means to decrease the brake pressure in said brake circuit, a second signal combination following said first signal combination to control said control means to maintain constant the decreased brake pressure in said brake circuit and a third signal combination following said second signal combination to control said control means to return said brake circuit to its normal operation; each of said first, second and third signal combinations including a plurality of Signals, each signal of said plurality of signals having a different characteristic derived from said deceleration signal; said first signal combination including a first signal indicating that said deceleration signal has achieved at least a given value, and a second signal which is a predetermined integrated value of said deceleration signal after said deceleration signal has achieved said given value; said second signal combination including a third signal indicating when said deceleration signal equals zero, and a fourth signal equal to a positive differential coefficient of said deceleration signal; and said third signal combination including said third signal, and a fifth signal equal to a negative differential coefficient of said deceleration signal.

Claim 13

A system according to claim 8, wherein said brake circuit includes a first pressure medium line connected between the output of a master cylinder and a wheel brake cylinder associated with said one of said given wheels, and a second pressure medium line connected between said wheel brake cylinder and a pressure medium reservoir; and said control means includes a normally open input valve connected in said first line, and a normally closed output valve connected in said second line, said first signal combination actuating said input valve from its normally open condition to a closed condition and actuating said output valve from its normally closed condition to an open condition, said second signal combination actuating said output valve to return to its normally closed condition, and said third signal combination actuating said input valve to return to its normally open condition.

Claim 14

A system according to claim 7, wherein said electronic circuit means includes an integrator coupled to said sensing means having a threshold level equal to said given value to produce said second signal, a first AND gate coupled to said sensing means and said integrator to produce said first signal combination, first and second bistable devices each of said bistable devices having two inputs, the output of one of said first and second bistable devices being coupled to said input valve for controlling the condition thereof and the output of the other of said first and second bistable devices being coupled to said output valve for controlling the condition thereof, one input of each of said first and second bistable devices being coupled to said first AND gate to set each of said first and second bistable devices to actuate said input valve to its closed condition and to actuate said output valve to its open condition, an inverter coupled to said sensing means to produce said third signal, a differentiator coupled to said sensing means, a positive polarity detector coupled to said differentiator to produce said fourth signal, a negative polarity detector coupled to said differentiator to produce said fifth signal, a second AND gate coupled to said inverter and said positive polarity detector to produce said second signal combination for coupling to the other input of said other of said bistable devices for reset thereof to actuate said output valve to its closed condition, and a third AND gate coupled to said inverter and said negative polarity detector to produce said third signal combination for coupling to the other input of said one of said bistable devices for reset thereof to actuate said input valve to its open condition.