Vibration damping shim structure

Details Vibration damping shim structure Vibration damping shim structure

2002-03-21

2002-11-19

Rodriguez, Pam (Department: 3683)

Brakes

Elements

Cooling and lubricating

C188S073370, C188S073350

Reexamination Certificate

active

06481545

ABSTRACT:

BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a vibration damping shim structure for use of a disc brake of an automobile and, more in particular, to the vibration damping shim structure reducing a high frequency noise (referred to as a squeal phenomenon), which is generated at braking.
2. Description of the Related Art
A conventional vibration damping shim structure for disc brake squealing prevention will be described.
FIGS. 2
to
3
shows a shim structure disclosed in Japanese Utility Model Application Laid-Open No. 62-45436.
A shim
60
which is disclosed in this official gazette has a stainless steel plate
62
and a metallic thin plate
66
coated with a heat-resistant and oil proof rubber
64
laminated toward the pressing direction (the direction of an arrow P
2
of
FIG. 2
) of a caliper claw
68
. The stainless steel plate
62
is arranged on the side of caliper claw
68
and, as shown in
FIG. 3
, a plurality of claws
70
is formed on its periphery. This claw
70
is constituted so that it is fitted to a back metal
72
of a brake pad. On the other hand, the thin plate
66
coated with the rubber
64
is arranged on the side of the back metal
72
and grease
74
is coated on an upper surface of the rubber
64
. As shown in
FIG. 3
, a plurality of notches and a grease pool
76
constituted by an oblong hole are formed on the thin plate
66
. The coated grease
74
is accumulated in this grease pool
76
. A claw
78
is formed on the periphery of the thin plate
66
similarly to the stainless steel plate
62
and is constituted so that it is fitted to the back plate
72
.
That is, as shown in
FIG. 2
, the shim
60
of the above constitution forms a six layer structure of the stainless steel sheet
62
, the grease
74
, the rubber
64
, the thin plate
66
, the rubber
64
and the grease
74
, which is directed toward the pressing direction of the caliper claw
68
.
The shim
60
of the above-described constitution can stop the vibration which is the cause of the “squealing noise” by a vibration insulating operation by interposing the rubber
64
or the grease
74
between the caliper claw
68
and the back metal
72
. Further, the vibration which is not stopped but propagated can be damped by a damping operation by a damping action attributable to an internal friction of the rubber
64
and a damping action attributable to a sliding friction of the grease
74
. Further, a relative displacement is generated between the back metal
72
(that is, the brake pad) and the shim
60
by the grease
74
coated between the back metal
72
and the thin plate
66
and the rubber
64
covered on the thin plate
66
. By frictional damping generated by this relative displacement, the vibration can be dampened. Further, the relative displacement is generated between the brake pad and the shim
60
, so that the constraint condition of the brake pad by the caliper claw
68
is changed. For this reason, the generation of the vibration can be reduced.
FIG. 4
shows a shim structure disclosed in Japanese Utility Model Application Laid-Open No. 4-3136.
A silicon gel layer
92
is provided in the center portion of a shim
90
which is disclosed in the official gazette. An adhesive layer
96
comprising an adhesive, an adhesive film and the like is formed on the side of the caliper claw
94
of the silicon gel layer
92
. A steel sheet
98
is arranged on the side of the caliper claw
94
of the adhesive layer
96
, and the steel sheet
98
is integrally bonded to the silicon gel layer
92
by the adhesive layer
96
.
On the other hand, similarly an adhesive layer
102
is formed on the side of a back metal
100
of the brake pad of the silicon gel layer
92
. A steel sheet
104
is arranged on the side of the back metal
100
of the adhesive layer
102
, and the steel sheet
104
is integrally bonded to the silicon gel layer
92
by the adhesive layer
102
. Further, an adhesive layer
106
comprising the adhesive, the adhesive film and the like is formed on the side of the back metal
100
of the steel sheet
104
, and the steel sheet
104
is bonded to the back metal
100
by the adhesive layer
106
.
That is, as shown in
FIG. 4
, the shim
90
of the constitution forms a six layer structure of the steel sheet
98
, the adhesive layer
96
, the silicon gel layer
92
, the adhesive layer
102
, the steel sheet
104
and the adhesive layer
106
, which is directed toward the pressing direction (the direction of the arrow p
3
of
FIG. 4
) of the caliper claw
94
as shown in the sectional view, and the shim
90
is integrally attached to the back metal
100
.
The silicon gel layer
92
having a good vibration insulating and flexibility is interposed in the center of the shim
90
of the constitution, whereby the shim prevents propagation of the vibration which is the cause of a “brake squealing” by both actions of the vibration insulating action and the damping action of the silicon gel layer
92
.
However, the shim structure of the conventional constitution is unable to obtain a sufficient “brake squealing” prevention effect as yet. That is, since the grease
74
is coated on the surface of the rubber
64
of the shim
60
in
FIGS. 2
to
3
, the relative displacement of the brake pad is expedited. For this reason, the effect by the friction damping and the vibration reducing action by a change in the constraint condition of the brake pad are excellent. However, since the damping action and the vibration insulating action are inferior to the silicon gel layer
92
of the shim
90
of
FIG. 4
, the “brake squealing” cannot be sufficiently prevented.
The shim
90
of
FIG. 4
comprises the silicon gel layer
92
, which is excellent in vibration insulating and, therefore, the effect by the damping action and the effect by the vibration insulating action are excellent. However, since the shim
90
and the back metal
100
of the brake pad are bonded, the relative displacement of the brake pad is small, and the effect by the frictional damping and the effect by the change of the constraint condition are poor. For this reason, the “brake squealing” cannot be sufficiently prevented.
In this way, either one of the conventional shims such as the shim
60
of FIG.
2
and the shim
90
of
FIG. 4
is partially limited in the effect of preventing the “brake squealing”, and the “brake squealing” cannot be sufficiently prevented so that the countermeasure to meet the situation has been earnestly desired.
SUMMARY OF THE INVENTION
In order to solve the problem, a shim structure shown in
FIGS. 5 and 6
(Japanese Patent Application Laid-Open No. 8-232998) has been proposed.
In the same drawings, a shim
10
is constituted by a rubber
36
as high frictional means having elasticity, a vibration damping steel plate
38
as damping means and a grease
40
as low frictional means having viscosity and fluidity.
To describe more in detail, the vibration damping steel plate
38
is arranged in the center of the shim
10
. The vibration damping steel plate
38
comprises a steel plate
44
consist of stainless and the like arranged at the side of the caliper claw
20
and a steel plate
46
consist of the same material as the steel plate
44
arranged at the side of the back metal
22
. The steel plate
44
and the steel plate
46
are arranged mutually in parallel, and a viscous member consists of acryl and the like is provided between the steel plate
44
and the steel plate
46
. The steel plate
44
, the viscous member
42
and the steel plate
46
are adhered and integrally formed. The surface at the side of the caliper claw
20
of the steel plate
44
is coated with a rubber
36
. On the other hand, on the surface at the side of the back metal
22
of the steel plate
46
, a plurality of grease pools
48
opened toward the pressing direction (the direction of the arrow P
1
of
FIG. 2
) of the caliper claw
20
is formed. Further, on the surface of the side of the back metal
22
of the steel plate
46
, grease
40
is coated and a part of this grease
40
i

Affiliated with

Also associated with

Rating

Vibration damping shim structure does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Vibration damping shim structure, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Vibration damping shim structure will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFUS-PAI-O-2992542