Attachment of a brake cable with an actuator of a parking brake

Details Attachment of a brake cable with an actuator of a parking brake Attachment of a brake cable with an actuator of a parking brake

2000-11-07

2001-05-22

Schwartz, Christopher P. (Department: 3613)

Brakes

Wheel

Transversely movable

C188S325000

Reexamination Certificate

active

06234281

ABSTRACT:

This invention relates to an actuator for a parking brake having structure for a attaching a brake cable to a lever therein.
BACKGROUND OF THE INVENTION
Many drum brakes include a parking brake lever which is activated by pulling on a cable to mechanically move first and second brake shoes into engagement with a drum to effect a brake application. Numerous mechanisms have been devised for attaching the cable to the end of the parking brake lever such as the ball retention structure disclosed in U.S. Pat. No. 5,142,935 and the resiliently positioned bushings as disclosed in U.S. Pat. No. 5,105,682 and 5,174,170. These connections function in an adequate manner under normal circumstances but with the use of four wheel disc brakes the drum-in-hat structure was introduced which limited the available space for components and as a result lever actuation such as disclosed in U.S. Pat. No. 5,180,037 was introduced. As disclosed in U.S. Pat. No. 5,180,037, the lever extends through the backing plate of the brake and the cable is attached by an eye member being located in a slot on the end of the lever. While this type of actuation is acceptable and functions in an adequate manner it is located on the outside of the brake structure where it is subjected to the elements. In order to make a more compact brake, the connection between the cable and actuator was located internally of the backing plate as disclosed in U.S. Pat. No. 5,311,793. The structure in U.S. Pat. No. 5,311,793 includes a spring clip which contracts to allow a button on the end of the cable to move past a fork legs on an actuation lever and later expands to prevent the button from moving out of engagement with the fork legs. An input force being applied by the cable to the fork legs to move the brake shoes into engagement with a drum to effect a brake application. In this structure, the spring clip is subjected to linear forces and after a period of time may suffer from fatigue or at least create noise.
SUMMARY OF THE INVENTION
A primary object of the present invention is to provide a connection for joining a cable with an actuator for a parking brake.
In more particular detail, the parking brake includes first and second brake shoes each having a first end that engages an anchor post on a backing plate and a second end that engages an adjuster. An actuator located adjacent the anchor post engages a first web on the first brake shoe and a second web on the second brake shoe. A brake cable connected to the actuator assembly provides a force for moving the first and second brake shoes into engagement with a drum to effect a brake application. The actuator is characterized by a housing having first and second spaced apart walls with a first end and a second end. The first and second ends of the first and second walls each have first and second ears. The first and second ears on the first ends are joined together adjacent a central plane mid-way between the first and second side walls to establish a first slot that receives the first web. The first ears on the second end of the first and second walls are joined together adjacent the central plane while the second ear on the first side wall is located adjacent the central plane but the second ear of the second side wall is located in a plane parallel with the second side wall. The first and second ears on the second end establishing a second slot that receives the second web. A lever having a first end with a shoulder thereon and a second end with a hook thereon is pivotally located on a pin that extends from the second ear on the first side wall to the second ear on the second side wall to position the shoulder in engagement the second web. A wave washer or spring located on the pin adjacent the second ear on the second side wall urges the first end of the lever into a position along the central plane. A button located on the cable and engaging the second end of the lever and with the cable being located in the hook provides an input force that is applied to the second end by pulling on the cable. The input force cause the lever to pivot on the pin and impart a force on the second web by way of the shoulder on the first end. At the same time, a corresponding force is exerted on the first web through the first and second side walls by way of the first slot. The input forces moves the first and second shoes into engagement with the drum to effect a brake application.
An advantage of the connection provided by the present invention resides in the wave washer which holds an actuation lever in a central plane through which an actuation force is applied to first and second webs on corresponding first and second brake shoes to effect a brake application.
A still further advantage of the present invention resides in the ease in which a button on a cable is connected to a hooked end on an lever of an actuator by pushing the button into a groove in a housing until the button moves past the hooked end and then pulling on the cable to position the button on a surface adjacent of the hooked end.
An object of this invention is to provide structure through which a cable is attached to a lever of an actuator by axially moving a lever as a button on the cable is inserted between the lever and a housing until the button moves past the lever and a spring repositions the lever along an a central plane such that on pulling on the cable the button now engages the end of the lever.


REFERENCES:
patent: 4887698 (1989-12-01), Hunt et al.
patent: 5070968 (1991-12-01), Evans
patent: 5180037 (1993-01-01), Evans
patent: 5322145 (1994-06-01), Evans
patent: 5360086 (1994-11-01), Charmat
patent: 5720367 (1998-02-01), Evans

Affiliated with

Also associated with

Rating

Attachment of a brake cable with an actuator of a parking brake does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Attachment of a brake cable with an actuator of a parking brake, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Attachment of a brake cable with an actuator of a parking brake will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFUS-PAI-O-2550123