초록 ▼

A collapsible push rod for a brake booster in a vehicle is provided, having first and second telescoping members, and retractable locking means for selectively locking the first and second members together against telescoping. During a frontal impact collision, the members telescope into one another

A collapsible push rod for a brake booster in a vehicle is provided, having first and second telescoping members, and retractable locking means for selectively locking the first and second members together against telescoping. During a frontal impact collision, the members telescope into one another to shorten the length of the push rod and compensate for rearward movement of the brake booster and forward movement of the driver. The push rod is operable in the collapsed state. The push rod is also re-settable after the collision, and includes features for returning the push rod to its normal un-telescoped length following the collision, if the push rod is not damaged in the collision. The retractable locking means includes an electrically actuated solenoid for selectively locking and unlocking the first and second members against telescoping, in response to an electrical signal applied to the solenoid.

대표청구항 ▼

1. A collapsible push rod for operatively connecting a brake pedal of a vehicle to a brake booster of the vehicle, for transmitting a braking force applied to the brake pedal by a driver of the vehicle to the brake booster, the collapsible push rod comprising:first and second telescoping members ope

1. A collapsible push rod for operatively connecting a brake pedal of a vehicle to a brake booster of the vehicle, for transmitting a braking force applied to the brake pedal by a driver of the vehicle to the brake booster, the collapsible push rod comprising:first and second telescoping members operatively connected to one another, and adapted for connection to the brake booster and the brake pedal;the first and second members being temporarily collapsible into one another during a frontal impact collision of the vehicle for shortening the push rod from a fully extended state to a collapsed state, to thereby compensate for potential rearward movement of the brake booster and forward movement of the driver during the collision;the push rod remaining operable for transmitting the braking force from the first member to the second member in the collapsed state;the push rod automatically returning to the fully extended state, following the collision, when the driver releases the braking force front the brake pedal; andthe push rod automatically re-setting to a fully operative condition in the fully extended state, following the collision, when the driver releases the braking force from the brake pedal, without repair or maintenance of the push rod. 2. The push rod of claim 1, further comprising, retractable locking means for selectively locking be first and second members together against telescoping. 3. The push rod of claim 2 wherein the retractable locking means includes an electrically actuated solenoid for selectively locking and unlocking the first and second members against telescoping, in response to an electrical signal applied to the solenoid. 4. The push rod of claim 3 wherein:the first member is adapted at one end thereof for attachment to a first element of a brake apparatus including the brake booster and brake pedal, and has an elongated generally cylindrical shaft portion thereof defining and extending from the one end along an axis of the push rod; andthe second member is adapted at one end thereof for attachment to a second element of the brake apparatus, the second member defining a generally cylindrical elongated bore therein for receipt of the shaft portion of the first member of the push rod, and also defining an annular wall surrounding the bore. 5. The push rod of claim 4 wherein:the shaft portion of the first member includes an annular groove for partial receipt therein of a locking ball;the second member includes a bole extending through the annular wall for passage therethrough of the locking ball;the push rod includes the locking ball disposed in the hole; andthe locking means is configured for maintaining the ball in the hole in partial engagement with the annular groove for locking the first and second members together to resist telescoping of the push rod, the locking means being further configured for selectively allowing the ball to disengage from the annular groove to allow the push rod to telescope. 6. The push rod of claim 5 wherein:the locking means includes a locking ring slidably disposed about and adapted for axial movement along the annular wall over the hole in the annular wall;the locking ring having an inner surface thereof defining axially spaced radially inner and outer sections thereof, the radially inner section thereof for holding the ball in partial engagement with the annular groove, and the radially outer section thereof for holding the ball when the ball is disengaged from the annular groove. 7. The push rod of claim 2 wherein the locking means includes means for moving the locking ring axially to selectively bring the radially inner and outer sections of the locking ring to bear against the ball. 8. The push rod of claim 7 wherein said means for moving the locking ring axially includes an electrical solenoid. 9. The push rod of claim 7 wherein the inner surface of the locking ring further defines a ramp between the radially inner and outer sections of the inner surface for fac ilitating movement of the locking ring over the ball. 10. The push rod of claim 7 wherein the locking means further includes a spring for urging the locking ring to move axially such that the radially inner section of the inner wall of the locking ring is disposed over the ball. 11. The push rod of claim 1 further including means for limiting the distance that the first and second members can telescope into one another. 12. The push rod of claim 11 wherein:the first member is adapted at one end thereof for attachment to a first element of a brake apparatus and has an elongated generally cylindrical shaft portion thereof defining and extending from the one end along an axis of the push rod;the second member is adapted at one end thereof for attachment to a second element of the brake apparatus, the second member defining a generally cylindrical elongated bore therein for receipt of the shaft portion of the first member of the push rod, an annular wall surrounding the bore, and an axially facing surface of the bore; andthe shaft portion and bore are configured such that the shaft portion will come to bear against the axially facing surface of the bore when the push rod has telescoped inward to a predetermined minimum length. 13. The push rod of claim 1 further including means for urging the first and second elements members to move axially outward from a telescoped position. 14. The push rod of claim 13 further including a spring for urging the first and second elements members to move axially outward from a telescoped position. 15. The push rod of claim 14 wherein:the first member is adapted at one end thereof for attachment to a first element of a brake apparatus and has an elongated generally cylindrical shaft portion thereof defining and extending from the one end along an axis of the push rod to a second end of the shaft portion defining an axially facing surface thereof;the second member is adapted at one end thereof for attachment to a second element of the brake apparatus, the second member defining a generally cylindrical elongated bore therein for receipt of the shaft portion of the first member of the push rod, an annular wall surrounding the bore, and an axially facing surface of the bore; andthe spring is disposed in the bore between the axially facing surface of the second end of the shaft portion of the first member and the axially facing surface of the bore. 16. A brake apparatus comprising:a brake booster; anda collapsible push rod adapted for operatively connecting a brake pedal of a vehicle to the brake booster for transmitting a braking force applied to the brake pedal by a driver of the vehicle to the brake booster, the collapsible push rod comprising:first and second telescoping members operatively connected to one another and the brake booster, and adapted for operative connection to the brake pedal;the first and second members being temporarily collapsible into one another during a frontal impact collision of the vehicle for shortening the push rod from a fully extended state to a collapsed state, to thereby compensate for potential rearward movement of the brake booster and forward movement of the driver during the collision,the push rod remaining operable for transmitting the braking force from the first member to the second member in the collapsed state;the push rod automatically returning to the fully extended state, following the collision, when the driver releases the braking force from the brake pedal; andthe push rod automatically re-setting to a fully operative condition in the fully extended state, following the collision, when the driver releases the braking force from the brake pedal, without repair or maintenance of the push rod. 17. The brake apparatus of claim 16, wherein the push rod further comprises:retractable locking means for selectively locking the first and second members together against telescoping;the retractable locking means of the push rod including an electrically actuated so lenoid for selectively locking and unlocking the first and second members against telescoping, in response to an electrical signal applied to the solenoid. 18. The vehicle of claim 17 further comprising an electrical circuit in the vehicle for sensing an impact and applying an electrical signal to the solenoid for unlocking the first and second members, thereby allowing them to telescope.