Self-adjusting caliper

• US 5,000,294 A
• Filed: 04/08/1985
• Issued: 03/19/1991
• Est. Priority Date: 04/08/1985
• Status: Expired due to Term

• Current Assignee: HB Specialty Products Group Incorporated
• Original Assignee: Hayes Industrial Brake Incorporated
• Inventors: Buckley, James A. V., Hunnicutt, Harry A.
• Primary Examiner(s): HALVOSA, GEORGE
• Application Number:
  US06/720,952
• Time in Patent Office: 2,171 Days
• Field of Search: 188/71.9, 188/72.7, 188/196 D, 188/196 BA, 192/70.25, 192/111 A
• US Class Current: 188/71.9
• CPC Class Codes: F16D 2121/02 Fluid pressure
• CPC Class Codes: F16D 2121/14 Mechanical
• CPC Class Codes: F16D 2123/00 Multiple operation forces
• CPC Class Codes: F16D 2125/36 Helical cams, Ball-rotating ramps
• CPC Class Codes: F16D 65/18 adapted for drawing members together , e.g. for disc brakes
• CPC Class Codes: F16D 65/567 for mounting on a disc brake

Abstract

A self-adjusting, wear-compensating device for a floating caliper disc brake of the type having a pair of brake pads positioned to engage the disc brake rotor, the device including a rotor and a stator mounted in the caliper housing, the rotary motion of the rotor being converted to linear motion in the stator toward one of the brake pads, a threaded shaft is mounted in a threaded bore in the stator and has one end positioned to engage the brake pad and the other end extending into the rotor, and a one-way clutch is mounted on the other end of the shaft and is operatively connected to the rotor to impart rotary movement to the shaft relative to the stator whenever the rotor rotates more than a predetermined amount to advance the shaft an incremental amount, the clutch is protected from overload damage by a star ring mounted on the shaft in a position to allow the clutch to slip on the shaft.

Claims

1. A self-adjusting wear-compensating device for a floating caliper brake for a brake disc of the type including

a caliper housing having brake pads mounted in said housing on the opposite sides of the brake disc, at least one of said pads being movable toward the other of said pads to impose a frictional restraint on the brake disc, said compensating device including

a stator mounted in said housing for movement toward and away from said one of said pads,

a threaded shaft supported in said stator for movement into engagement with said one of said brake pads,

a rotor mounted in said housing for rotary motion relative to said stator,

cam means positioned between said rotor and said stator for advancing said stator and said shaft into engagement with said one of said brake pads,

a one way roller clutch mounted on said threaded shaft for rotating said shaft relative to said stator as said stator is advanced toward said brake pad by the motion of said rotor and to rotate freely with respect to said shaft when said shaft is moved away from said brake pad,

lost motion means operatively connecting said clutch to said rotor to allow said rotor to move a predetermined distance relative to said clutch before said clutch rotates said threaded shaft whereby said shaft will be advanced with respect to said stator an exponential incremental amount each time the rotor is rotated beyond said predetermined distance, and

means for frictionally connecting said shaft to said roller clutch to allow said roller clutch to slide with respect to said shaft when the load on the shaft is sufficient to set the brake.

2. The device according to claim 1 wherein said lost motion means comprises

a tab mounted on said clutch and

a slot in said rotor having a width greater than the width of said tab, said tab being aligned in said slot whereby said rotor will rotate with respect to said stator a predetermined distance equal to the difference between the width of the slot and the width of the tab before imparting rotary motion to the clutch housing to rotate the shaft relative to the stator.

3. In a floating caliper for a disc brake, the caliper including,

a housing and a pair of brake pads mounted in the housing in a position to engage the sides of a disc brake rotor, the improvement comprising

an infinitely variable self-adjusting device including a stator mounted in the housing and having a threaded bore,

a threaded shaft mounted in said threaded bore in said stator and having one end operatively positioned to engage one of said pads, means for moving said stator and said shaft toward said one of said pads to impose a frictional restraint on the rotor, said moving means including

a one-way roller clutch mounted on said shaft for imparting rotary motion to said threaded shaft relative to said stator after said shaft is moved into engagement with said one of said pads whereby said shaft may be advanced with respect to said stator an incremental distance after said shaft engages said one of said pads, and means for frictionally connecting said roller clutch to said shaft to allow said clutch to rotate with respect to said shaft when the load on said shaft is sufficient to set the brake.

4. The caliper according to claim 3 wherein said moving means includes

a rotor mounted in the housing and

cam means positioned between said rotor and said stator to convert rotary motion of said rotor to linear motion of said stator.

5. The caliper according to claim 3 wherein said engaging means comprises a tab on said clutch and a slot in said rotor having a width greater than said tab whereby said rotor will rotate a predetermined distance before imparting any rotary motion to said clutch.