Skid control system including cycling and checking circuit for plural modulating valve

Claim 2

A skid control system for a wheeled vehicle comprising: a plurality of fluid control valves controllably actuable in response to a skid control signal for controlling the pressure to the brakes of the wheels of the vehicle, actuating means automatically actuable by the vehicle operator in operating the vehicle, valve cycling means connected to the actuating means of the vehicle and being actuated in response to actuation of the actuating means for cycling the valves without the prior occurrence of the control signal whereby the valves will be cycled at determinable times in order to prevent deterioration of the valves from inaction, said valve cycling means including means responsive to the actuation of the brakes of said vehicle by the vehicle operator for preventing simultaneous actuation of all of said valves during actuation of the brakes of said vehicle by the vehicle operator.

Claim 3

A skid control system according to claim 1 having two fluid control valves independently controllably actuated in response to separate skid control signals.

Claim 4

A skid control system according to claim 1 having a first fluid control valve for controlling the pressure to the brakes of the front wheels of the vehicle in response to a front skid control signal and a second fluid control valve for controlling the pressure to the brakes of the rear wheels of the vehicle in response to a rear skid control signal.

Claim 5

A skid control system according to claim 1 wherein said actuating means is the ignition switch of the vehicle.

Claim 6

A skid control system according to claim 1 wherein said valves have a determinable cycle of operation and further including valve checking means for sensing a deviation from said determinable cycle of operation of said valves during cycling thereof.

Claim 7

A skid control system according to claim 1 wherein each of said valves includes a movable member and wherein said valve cycling means causes said movable member to move to an extreme actuated position for release of brake pressure to an associated brake and to return to a deactuated position for reapplication of brake pressure to said associated brake.

Claim 8

A skid control system according to claim 1 wherein said means responsive to the actuation of the brakes of said vehicle prevents actuation of all of said valves during the actuation of the brakes of said vehicle by the vehicle operator.

Claim 9

A skid control system according to claim 1 wherein said means responsive to the actuation of the brakes of said vehicle prevents the actuation of fewer than all of said valves during actuation of the brakes of said vehicle by the vehicle operator.

Claim 10

A skid control system according to claim 1 wherein said means responsive to the actuation of the brakes of said vEhicle prevents the actuation of all but one of said valves during actuation of the brakes of said vehicle by the vehicle operator.

Claim 11

A skid control system according to claim 1 having two fluid control valves independently controllably actuated in response to separate skid control signals and wherein said means responsive to the actuation of the brakes of said vehicle prevents actuation of both of said valves during the actuation of the brakes of said vehicle by the vehicle operator.

Claim 12

A skid control system according to claim 1 having two fluid control valves independently controllably actuated in response to separate skid control signals and wherein said means responsive to the actuation of the brakes of said vehicle prevents actuation of one of said valves during the actuation of the brakes of said vehicle by the vehicle operator.

Claim 13

A skid control system according to claim 1 wherein said vehicle has a brake light switch and wherein said means responsive to the actuation of the brakes of said vehicle is connected to said brake light switch to respond thereto.

Claim 14

A skid control system for a wheeled vehicle comprising: at least two fluid control valves independently controllably actuated in response to separate skid control signals having a determinable cycle of operation for controlling the pressure to respective ones of the brakes of the wheels of the vehicle, actuating means automatically actuable by the vehicle operator, valve cycling means connected to the actuating means of the vehicle and being actuated in response to actuation of the actuating means for cycling the valves without the prior occurrence of the control signal whereby the valves will be cycled at determinable times in order to prevent deterioration of the valves from inaction, said valve cycling means including means responsive to the actuation of the brakes of said vehicle by the vehicle operator for preventing simultaneous actuation of all of said valves during actuation of the brakes of said vehicle by the vehicle operator and valve checking means for sensing a deviation from said determinable cycle of operation of said valves during cycling thereof.

Claim 15

A skid control system for a wheeled vehicle comprising: at least two fluid control valves independently controllably actuated in response to separate skid control signals having a determinable cycle of operation for controlling the pressure to respective ones of the brakes of the wheels of the vehicle, actuating means automatically actuable by the vehicle operator, valve cycling means connected to the actuating means of the vehicle and being actuated in response to actuation of the actuating means for cycling the valves without the prior occurrence of the control signal whereby the valves will be cycled at determinable times in order to prevent deterioration of the valves from inaction, said valve cycling means including means responsive to the actuation of the brakes of said vehicle by the vehicle operator for preventing simultaneous actuation of all of said valves during actuation of the brakes of said vehicle by the vehicle operator and valve checking means for sensing a deviation from said determinable cycle of operation of said valves during cycling thereof.

Claim 16

A skid control system according to claim 13 having a first fluid control valve for controlling the pressure to the brakes of the front wheels of the vehicle in response to a front skid control signal and a second fluid control valve for controlling the pressure to the brakes of the rear wheels of the vehicle in response to a rear skid control signal.

Claim 17

A skid control system according to claim 14 wherein said actuating means is the ignition switch of the vehicle.

Claim 18

A skid control system according to claim 15 wherein each of said valves includes a movable member and wherein said valve cycling means causes said movable member to move to an extreme actuated position for release of brake pressure to an associated brake and to return to a deactuated position for reapplication of brake pressure to said associated brake.

Claim 19

A skid control system according to claim 16 wherein said vehicle has a brake light switch and wherein said means responsive to the actuation of the brakes of said vehicle is connected to said brake light switch to respond thereto.

Claim 20

A skid control system according to claim 17 wherein said means responsive to the actuation of the brakes of said vehicle prevents actuation of both of said valves during the actuation of the brakes of said vehicle by the vehicle operator.

Claim 21

A skid control system according to claim 17 wherein said means responsive to the actuation of the brakes of said vehicle prevents actuation of one of said valves during the actuation of the brakes of said vehicle by the vehicle operator.

Claim 22

A skid control system for a wheeled vehicle comprising: at least two fluid control valves independently controllably actuated in response to separate skid control signals having a determinable cycle of operation for controlling the pressure to respective ones of the brakes of tHe wheels of the vehicle, actuating means automatically actuable by the vehicle operator, valve cycling means connected to the actuating means of the vehicle and being actuated in response to actuation of the actuating means for cycling the valves without the prior occurrence of the control signal whereby the valves will be cycled at determinable times in order to prevent deterioration of the valves from inaction, said valve cycling means including brake cycling inhibit means responsive to the actuation of the brakes of said vehicle by the vehicle operator for inhibiting actuation of at least one of said valves during actuation of the brakes of said vehicle by the vehicle operator and valve checking means for sensing a deviation from said determinable cycle of operation of said valves during cycling thereof.

Claim 23

A skid control system for a wheeled vehicle comprising: at least two fluid control valves independently controllably actuated in response to separate skid control signals having a determinable cycle of operation for controlling the pressure to respective ones of the brakes of tHe wheels of the vehicle, actuating means automatically actuable by the vehicle operator, valve cycling means connected to the actuating means of the vehicle and being actuated in response to actuation of the actuating means for cycling the valves without the prior occurrence of the control signal whereby the valves will be cycled at determinable times in order to prevent deterioration of the valves from inaction, said valve cycling means including brake cycling inhibit means responsive to the actuation of the brakes of said vehicle by the vehicle operator for inhibiting actuation of at least one of said valves during actuation of the brakes of said vehicle by the vehicle operator and valve checking means for sensing a deviation from said determinable cycle of operation of said valves during cycling thereof.

Claim 24

A skid control system according to claim 20 having a first fluid control valve for controlling the pressure to the brakes of the front wheels of the vehicle in response to a front skid control signal and a second fluid control valve for controlling the pressure to the brakes of the rear wheels of the vehicle in response to a rear skid control signal.

Claim 25

A skid control system according to claim 21 wherein said actuating means is the ignition switch of the vehicle.

Claim 26

A skid control system according to claim 22 wherein each of said valves includes a movable member and wherein said valve cycling means causes said movable member to move to an extreme actuated position for release of brake pressure to an associated brake and to return to a deactuated position for reapplication of brake pressure to said associated brake.

Claim 27

A skid control system according to claim 23 wherein said vehicle has a brake light switch and wherein said means responsive to the actuation of the brakes of said vehicle is connected to said brake light switch to respond thereto.

Claim 28

A skid control system according to claim 20 wherein said means responsive to the actuation of the brakes of said vehicle prevents actuation of both of said valves during the actuation of the brakes of said vehicle by the vehicle operator.

Claim 29

A skid control system according to claim 20 wherein said means responsive to the actuation of the brakes of said vehicle prevents actuation of one of said valves during the actuation of the brakes of said vehicle by the vehicle operator.