US20080006490A1

US20080006490A1 - Retention spring for brake pressure pads

Info

Publication number: US20080006490A1
Application number: US11/845,279
Authority: US
Inventors: Philip Jedele; Seiji Nishimura; Tadasake Fujiwara
Original assignee: Akebono Corp North America
Current assignee: Akebono Brake Corp
Priority date: 2004-12-14
Filing date: 2007-08-27
Publication date: 2008-01-10
Also published as: CN1793685A; US20060124408A1; EP1672239B1; DE602005001191T2; ES2287860T3; US7267208B2; EP1672239A1; JP2006170443A; DE602005001191D1

Abstract

A brake caliper has a retention spring to eliminate excessive movement of the pressure plates or pad pin with respect to the caliper housing. The retention spring has a pad pin contacting portion to exert a force on the pad pin. The spring includes a retention portion continuous with the pad pin portion to provide counterforce to maintain the pad pin in position.

Description

The present invention relates to brake calipers and, more particularly, to brake pressure plate retention springs.

BACKGROUND OF THE INVENTION

Brake calipers surround wheel rotors to brake or slow the movement of the rotor and, in turn, a machine or vehicle. In order to slow the movement of the rotor, the caliper includes brake pads or brake pressure plates with a friction material which contacts the rotor to stop movement of the rotor. Some brake or pressure pads generally are of the hanging type. Thus, the pressure plate includes an aperture which enables a pad pin to pass through the aperture to secure it with the caliper housing. In order to prohibit noise or rattling of the pressure plate on the pad pin, large springs are used to exert a force on the pressure plate to keep it in position. In other types of hanging pressure plates, the plates include a small hole with tight tolerances so that the guiding pad pin fits tightly in the pressure plate hole. The same can be said of the caliper aperture. This can lead to corrosion which, in turn, can lead to difficult servicing, high drag and potential binding of the pads. Thus, it is desirable to have a hanging pressure plate that has a large clearance hole to reduce corrosion and minimize concerns. The extra clearance must then be taken up by the return clip.

SUMMARY OF THE PRESENT INVENTION

The present invention provides the art with a pressure plate retention spring. The retention spring has a compact design and is inexpensive to manufacture. The present invention enables a pressure plate to be used with a large opening wherein the retention spring takes up the play to reduce noise and rattle of the pressure plate on the brake caliper housing.
In accordance with the present invention, a retention spring includes a pad pin contacting portion which exerts a force on the pad pin and a pressure plate. The spring also includes a retention portion which is continuous with the contacting portion. The retention portion provides a counterforce to retain the spring clip in position. The retention spring may be coupled between the pad pin and the pressure plate or be mounted on a pad pin support on the caliper housing.
From the following detailed description taken in conjunction with the accompanying drawings and claims, other objects and advantages of the present invention will become apparent to those skilled in the art.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 illustrates a perspective view of a brake caliper in accordance to a first embodiment in the present invention.
FIG. 2 is an enlarged partial side plan view of FIG. 1.
FIG. 3 is an enlarged perspective view of the retention spring of FIG. 1.
FIG. 4 is a perspective view of a brake caliper including a second embodiment of the present invention.
FIG. 5 is a perspective view of one of the springs of FIG. 4.
FIG. 6 is a cross-section view of a second or auxiliary spring of FIG. 4.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Turning to the figures, particularly FIG. 1, a brake caliper is illustrated and designated with the reference numeral 10. The caliper includes a housing 12 with a pair of pressure plates 14 and 16 positioned within the housing 12. The pressure plates 14 and 16 include a friction material 18 which abuts a rotor (not shown) to stop rotation of the rotor. The pressure plates 14 and 16 include a support portion 20 which includes an aperture 22 to enable a pad pin 24 to pass therethrough to secure the pressure plates 14 and 16 on the caliper housing 12. The pad pin 24 has its ends secured in housing support members 26 and 28. The housing support members 26 and 28 are substantially identical.
Turning to FIG. 2, a retention spring 30 is illustrated positioned in the aperture 22 of one of the pressure plates 14 or 16. It is noted that the retention spring 30 is normally positioned in both of the pressure plates 14 and 16. The retention spring 30 includes a pad pin contacting portion 32 and retention portions 34 and 36. The retention portions 34 and 36 are substantially identical. The retention spring 30 has an overall figure eight configuration being open at one of its sides opposing the pad pin contacting portion 32. Ordinarily, the pad pin contacting portion 32 has a concave surface which is complementary to the convex arcuate portion of the pad pin 24. However, the contacting portion 32 may be flat. The retention portions 34 and 36 of the retention spring have convex arcuate portions which contact the walls 38 and 40 defined by the aperture 22. The ends of the retention portions 34 and 36, at the opening of the figure eight configuration are directed toward the pad pin contacting portion 32.
The retention portions 34 and 36 apply a force F1 onto the walls 38 and 40 to retain the retention spring 30 within the aperture 22. A force F2 is exerted by the pad pin contacting portion 32 to force the pad pin against the wall 42 of the aperture 22.
Also, the retention portions 34 and 36 exert a force on wall portion 44 of aperture 22. The wall 44 exerts a counterforce on the retention portions 34 and 36 which, in turn, exert a force on the pad pin 24. The retention spring 30 retains the pad pin, as well as the pressure plates, in position to substantially reduce noise and rattle which may occur due to vibration of the caliper.
Turning to FIGS. 4 and 5, a second embodiment of the present invention is illustrated. The brake caliper 10 is substantially the same as that in FIG. 1 and has been identified with the same reference numeral. Likewise, the pressure plates, as well as the pad pin and pad pin support members, are the same and have been identified with the same reference numeral.
Retention spring 50 surrounds the pad pin support 26 to exert a force on the pad pin 24. The retention spring 50 has an overall closed rectangular shape with two greater legs 52 and 54 and two lesser legs 56 and 58. The greater legs 52 and 54 both include pad pin contacting portions 60 and 62. These pad pin contacting portions 60 and 62 may have an arcuate concave surface to receive the pad pin 24. As can be seen in FIG. 5, the retention spring 50 is positioned surrounding the pad pin support 26. The pad pin 24 contacts the contacting portion 60 and 62 forcing the spring 50 downward at that area. In turn, the lesser legs 56 and 58, which ride on the walls of the supports 26 and 28, push against the downward force of the pad pin 24. In turn, this forces the contacting portion 60 and 62 to exert an upward force on the pad pin 24 to maintain the pad pin in position to reduce noise and rattle due to vibration.
Also, the design my include an additional spring member 80. The additional spring member 80 has an overall H shape with its vertical legs 82 and 84 in contact with a surface of the pressure plates 14 and 16. The legs 82 and 84 apply a downward force on both of the pressure plates 14 and 16 at two different positions. The horizontal leg 86 of the spring 80 may include an arcuate concave portion to contact the pad pin 24. The horizontal leg 86 as seen in FIG. 6, is raised with respect to the vertical legs 82 and 84 so that when the horizontal leg 86 is positioned on the pad pin 24, a downward force is exerted onto the legs 82 and 84. This downward force, is in turn, exerted on the pressure plates 14 and 16 to hold the pressure plates 14 and 18 against noise and rattling.
The retention springs and auxiliary springs can be stamped from a metal spring material. Also, the retention spring could be manufactured from a metal wire material. The retention springs are relatively small and have a minimal cost. The springs provide necessary forces between the pad pin and pressure plates to reduce excessive movement which causes noise or rattle. Also, due to the minimal contact between the retention springs and the other elements, a potential for corrosion is reduced.
While the above detailed description of the invention is merely exemplary in nature, variations that do not depart from the gist of the invention are intended to be within the scope of the invention. Such variations are not to be regarded as a departure from the spirit and scope of the invention.

Claims

1-25. (canceled)

26: A spring clip for causing contact between a brake pad pin and a pressure plate or pad pin support of a brake caliper, the spring clip comprising:

a spring portion for contacting and exerting a force against a brake pad pin to hold the brake pad pin against a single pressure plate or pad pin support; and

a retention portion configured to provide counter force in response to the exerted force, the retention portion including portions located on opposite sides of the spring portion which engage the pressure plate or pad pin support,

wherein the spring clip is configured to engage a single brake pad pin and a single pressure plate or pad pin support.

27: The spring clip of claim 26, wherein the sum of the counter force is generally equal to the sum of the exerted force.

28: The spring clip of claim 27, wherein the counter force includes at least one directional force generally perpendicular to the exerted force.

29: The spring clip of claim 27, wherein the counter force includes at least one directional force generally parallel to the exerted force.

30: The spring clip of claim 26, wherein the spring clip includes a depth that is generally equal to a depth of the pressure plate or pad support.

31: The spring clip of claim 26, wherein the spring clip is formed of stamped metal and includes a material depth that extends through a length of the spring clip and which is greater than the material thickness of the stamped metal.

32: The spring clip of claim 31, wherein the spring portion includes a contact portion for engaging the brake pad pin, the contact portion including a concave arcuate portion having a shape complementary to the brake pad pin.

33: The spring clip of claim 32, wherein the retention portion includes two opposing C-shaped members located on opposite sides of the spring portion and facing each other to form two openings extending through the depth of the spring clip.

34: The spring clip of claim 26, wherein the spring clip is formed of a single continuous wire forming a closed rectangular shape, the spring clip configured to entirely surround a portion of the pad pin support.

35: The spring clip of claim 34, wherein the spring portion includes a contact portion for engaging the brake pad pin, the contact portion including two concave arcuate wire portions having a shape complementary to the brake pad pin and wherein the retention portion includes two members located on opposite sides of the spring portion and extending away from each other.

36: A brake caliper comprising:

a caliper housing including an inboard side and an outboard side separated by a rotor gap, the inboard and outboard sides including a pad pin support defining an opening for receiving a brake pad pin;

a first brake pad including a first pressure plate and a second brake pad including a second pressure plate, the first and second pressure plates each defining an opening for receiving the brake pad pin;

a first spring clip exerting a force against the brake pad pin in a direction to hold the brake pad pin against the first pressure plate or pad pin support; and

a second spring clip exerting a force against the brake pad pin in a direction to hold the brake pad pin against the second pressure plate or pad pin support,

wherein the first and second spring clips are each configured to engage a single brake pad pin.

37: The brake caliper of claim 36, wherein the first and second spring clip each include:

a spring portion contacting and exerting the force against the brake pad pin; and

a retention portion providing a counter force in response to the exerted force, the retention portion including portions located on opposite sides of the spring portion.

38: The brake caliper of claim 36, wherein the first and second spring clip include a depth that is generally equal to a depth of the pressure plate or pad pin support.

39: The brake caliper of claim 36, wherein each of the first and second spring clips are entirely located within the opening formed in the first and second pressure plate, respectively.

40: The brake caliper of claim 36, wherein each of the first and second spring clip entirely surround a portion of the first and second brake pad pin support.

41: The spring clip of claim 40, wherein the spring clip is formed of a single continuous wire forming a closed rectangular shape.

42: The spring clip of claim 41, wherein the spring portion includes a contact portion for engaging the brake pad pin, the contact portion including two concave arcuate wire portions having a shape complementary to the brake pad pin and wherein the retention portion includes two members located on opposite sides of the spring portion and extending away from each other.

43: The spring clip of claim 37, wherein the first and second spring clips are formed of stamped metal and includes a material depth that extends through a length of the spring clip and which is greater than the material thickness of the stamped metal.

44: The spring clip of claim 43, wherein the spring portion of the first and second spring clips each include a contact portion for engaging the brake pad pin, the contact portion including a concave arcuate portion having a shape complementary to the brake pad pin, and wherein the retention portion of the first and second spring clips each include two opposing C-shaped members located on opposite sides of the spring portion and facing each other to form two openings extending through the depth of the spring clip.

45: The brake caliper of claim 36, further comprising a third spring clip, the third spring clip includes:

a spring portion exerting a force against the brake pad pin in a direction to hold the brake pad pin against the inboard and outboard pad pin support; and

a retention portion providing a counter force in response to the exerted force, the retention portion including portions located on opposite sides of the spring portion and contacting the first and second pressure plates.