Apparatus for performing friction material

Apparatus for performing a friction material includes a friction material-charging device for charging an appropriate amount of a friction material into a cavity in an intermediate die member receiving a lower die member therein; a leveling device including a base having a plurality of narrow bars depending from the base, a first elevator mechanism for vertically moving the base, so that when the base is moved downward, the narrow bars are inserted into the cavity, and a device for imparting a horizontal reciprocal movement to the base when the base is moved downward, so as to level the friction material by the narrow bars; a recess-pressing device including a push rod, and a second elevator mechanism for vertically moving the push rod, so that when the push rod is moved downward, the push rod is inserted into the cavity in the intermediate die member so as to press the friction material into the recess; and a pressing device including a third elevator mechanism for vertically moving an upper die member, so that when the upper die member is moved downward, the upper die member is fitted in the cavity in the intermediate die member so as to press the friction material.

BACKGROUND OF THE INVENTION 
1. Field of the Invention 
The present invention relates to an apparatus for preforming a friction 
material for a brake. 
2. Related Art 
Conventionally, the preforming of a friction material of the type described 
has been effected by a manual operation. More specifically, 
conventionally, a friction material is manually charged into an 
intermediate die member receiving a lower die member therein, and the 
friction material received in the intermediate die member in a heaped-up 
manner is generally leveled. Then, bars are pushed into the thus leveled 
friction material so as to force the friction material into recessed 
formed in the lower die member. Then, the lower and intermediate die 
members are connected integrally with each other, and are transferred to a 
pressing machine, and then the friction material is pressed by an upper 
die member fitted in the intermediate die member, so that the friction 
material is preformed into a predetermined shape. 
However, since the operation of this conventional preforming method is 
manually carried out, the efficiency of the operation is not satisfactory. 
And besides, during the preforming operation, the operator must directly 
touch the friction material containing asbestos which is a harmful 
material. Thus, the operator is exposed to such bad environment. 
SUMMARY OF THE INVENTION 
It is therefore an object of this invention to provide an apparatus for 
preforming a friction material which overcomes the above deficiencies of 
the conventional apparatus. That is, an object of the invention is to 
provide an apparatus for preforming a friction material by which the 
preformed friction material can automatically be produced by the 
preforming apparatus, and the efficiency of the operation is greatly 
improved, without varying the quality of the preformed products. 
It is another object of the invention to provide an apparatus for 
preforming a friction material by which the working environment is greatly 
improved. 
The above and other objects can be achieved by a provision of an apparatus 
for preforming a friction material which, according to the present 
invention, has a preform die comprising a lower die member having a recess 
formed in an upper surface thereof, an intermediate die member having a 
cavity for receiving the lower die member therein, and an upper die member 
slidably engageable in the cavity in the intermediate die member, a 
friction material-charging device for charging an appropriate amount of a 
friction material into the cavity in the intermediate die member receiving 
the lower die member therein, a leveling device comprising a base having a 
plurality of narrow bars depending from the base, a first elevator means 
for vertically moving the base, so that when the base is moved downward, 
the narrow bars are inserted into the cavity in the intermediate die 
member, and a device for imparting a horizontal reciprocal movement to the 
base when the base is moved downward, so as to level the friction material 
by the narrow bars, a recess-pressing device comprising a push rod, and a 
second elevator means for vertically moving the push rod, so that when the 
push rod is moved downward, the push rod is inserted into the cavity in 
the intermediate die member so as to press the friction material into the 
recess, and a pressing device comprising a third elevator means for 
vertically moving the upper die member, so that when the upper die member 
is moved downward, the upper die member is fitted in the cavity in the 
intermediate die member so as to press the friction material. 
The intermediate die member can have a plurality of cavities for receiving 
a plurality of lower die members, respectively. 
In the friction material-charging device, an appropriate amount of the 
friction material is charged into the cavity in the intermediate die 
member, receiving the lower die member therein, in a heaped-up manner. The 
intermediate die member supplied with the friction material is transferred 
or moved to a position beneath the leveling device. Then, the first 
elevator means is driven to move the base downward so as to insert the 
plurality of narrow bars into the cavity in the intermediate die member, 
so that the narrow bars are extended into the heaped-up friction material. 
Then, the horizontal movement-imparting device is driven to impart a 
reciprocal horizontal movement to the base, so that the heaped-up friction 
material on the lower die member is raked by the plurality of narrow bars 
in right and left directions and is generally level or made flat. After 
this leveling operation is finished, the base is returned or moved upward 
by the first elevator means to the position where the narrow bars will not 
interfere with the intermediate die member. The intermediate die member is 
further transferred to a position beneath the recess-pressing device. 
Then, the second elevator means is driven to move the push rod downward 
and is pushed into the recess in the lower die member. As a result, part 
of the generally-leveled friction material is pressed or forced into the 
recess, and the recess is fully filled with the friction material. The 
friction material in the recess undergoes a suitable compressive force. 
After the friction material is pressed into the recess, the push rod is 
returned or moved upward to the position where the push rod will not 
interfere with the intermediate die member. Then, the intermediate die 
member is further transferred to a position beneath the pressing device. 
Then, the upper die member is moved downward by the third elevator means 
and is fitted into the cavity in the intermediate die member, so that the 
upper die member is moved downward in the cavity to press the friction 
material, thereby preforming the material into a predetermined shape.

DESCRIPTION OF THE PREFERRED EMBODIMENTS 
The invention embodied in an apparatus for preforming a friction material 
for use in a disc brake will now be described with reference to the 
drawings. 
FIGS. 1 to 6 show one preferred embodiment of the invention. A friction 
material-charging device 1 is adapted to charge an appropriate amount of a 
friction material 2 into an intermediate die member 8 receiving a lower 
die member 9 therein. The friction material 2 is formed by uniformly 
mixing or blending together a reinforcing material, friction modifiers, a 
binder, etc., using an agitator (not shown). The thus formed friction 
material 2 is contained in a can 3, and is transferred to the friction 
material-charging device 1. 
A turn device 4 is mounted on the upper end of the friction 
material-charging device 1. The can 3 containing the friction material 2 
is turned over by the turn device 4 about an axis O, so that the friction 
material 2 is charged from the can 3 into a container 5a of a blender 
supply device 5. The container 5a has a discharge port 5b formed through a 
central portion of the bottom thereof. A rotatable shaft 5c disposed 
horizontally is received in a lower portion of the container 5a, and a 
wire 5f is spirally wound around the rotatable shaft 5c. The rotatable 
shaft 5c and the spiral wire 5f jointly constitute a screw feeder 5d. As 
shown in FIG. 6, a plurality of posts 5e extend radially from the 
rotatable shaft 5c, and the spiral wire 5f is fixedly secured to the 
distal ends of the posts 5e. The wire 5f is oppositely spiral much like 
right-handed and left-hand screws on opposite sides of the central portion 
thereof. When the rotatable shaft 5c is rotated in one direction by a 
motor 5g, the friction material 2 in the container 5a is mixed and moved 
toward the central discharge port 5b. 
The friction material 2 discharged from the discharge port 5b is 
transferred by a screw feeder 6 rotated by a motor 6a, and is fed to 
vibration feeders 7 via a pair of discharge port 6b. The screw feeder 6 is 
also oppositely spiral much like right-handed and left-hand screws on 
opposite sides of the central portion thereof, and feeds the friction 
material 2 to the vibration feeders 7 via the right and left discharge 
ports 6b (FIG. 1). At each of the subsequent stages, a pair of relevant 
devices are arranged in juxtaposed relation, and a pair of preformed 
products are produced at the same time. For the purpose of simplifying the 
description, the process of preforming one product (brake disc) will be 
described hereinafter. 
The vibration feed 7 includes a trough 7b vibrated by a vibration source 7a 
whose vibration frequency is variable. The vibration source 7a applies 
vibrations of a predetermined frequency to the trough 7b for a 
predetermined time period, so that an appropriate amount of the friction 
material 2 metered is fed to the intermediate die member 8 placed on a 
transfer device 31 associated with a conveyer 31. As shown in FIG. 2, the 
intermediate die member 8 is of a tubular shape and has a cavity 8a 
corresponding in cross-section to the lower die member 9. The lower die 
member 9 is fitted in the lower end portion of the intermediate die member 
8. Therefore, the friction material 2 fed from the trough 7b to the 
intermediate die member 8 is heaped up on the lower die member 9. 
The intermediate die member 8 supplied with the friction material 2 is 
transferred by the conveyer 30, and sequentially passes past a leveling 
device 10, a recess-pressing device 15 and a pressing device 18. 
As shown in FIG. 2, the leveling device 10 comprises a base 11 having a 
plurality of narrow bars 12 depending perpendicularly from the base 11, a 
first elevator mechanism 13 associated with the base 11, and a horizontal 
movement-imparting mechanism 14 associated with the base 11. The first 
elevator mechanism 13 serves to move the base 11 vertically, that is, 
upward and downward. When the base 11 is moved downward by the first 
elevator mechanism 13, the narrow bars 12 are inserted into the 
intermediate die member 8, so that the distal end portions of the narrow 
bars 12 are extended into the heaped-up friction material 2. The first 
elevator mechanism 13 is constituted by a rack-and-pinion mechanism, a 
reciprocal-type cylinder, etc. The horizontal movement-imparting mechanism 
14 imparts a horizontal reciprocal movement to the base 11 when the base 
11 is moved downward. The horizontal movement-imparting mechanism 14 is 
constituted by a cam mechanism, a reciprocal slider crank, etc. 
As shown in FIG. 3, the recess-pressing device 15 comprises a second 
elevator mechanism 17 which is supported by a support base 16 and moves a 
pair of push rods 22 upwardly and downwardly. When the push rods 22 are 
moved downward by the second elevator mechanism 17, the push rods 22 are 
inserted into the intermediate die member, so that the distal end portions 
of the push rods 22 are inserted respectively into a pair of recesses 9a 
in the lower die member 9, thereby pushing the friction material 2 into 
the pair of recesses 9a. The second elevator mechanism 17 is constituted 
by a rack-and-pinion mechanism, a reciprocal-type cylinder, etc. The pair 
of recesses 9a are provided for forming a pair of projections on the 
preformed friction material 2 for a disc brake. The pair of projections 
are fitted respectively in a pair of recesses in a backing plate, thereby 
increasing the strength of connection between the frictional material 2 
and the backing plate. 
As shown in FIG. 4, the pressing device 18 comprises a third elevator 
mechanism 21 which is supported by a support base 19 and moves a support 
member 20 upwardly and downwardly. The support member 20 has an upper die 
member 23 fixedly mounted on the lower end of the support member 20, the 
upper die member 23 being in the form of a flat plate. When the support 
member 20 is moved downward by the third elevator mechanism 21, the upper 
die member 23 is fitted into the intermediate die member 8 so as to press 
the friction material 2 on the lower die 9. The third elevator mechanism 
21 is constituted by a pressing machine or the like. Thus, a preforming 
die is constituted by the intermediate die member 8, the lower die member 
9 and the upper die member 23. 
The operation of the apparatus for preforming a friction material according 
to the invention will now be described. 
The friction material 2 contained in the container 3 in the friction 
material-charging device 1 is sequentially fed via the blender supply 
device 5, the screw feeder 5d, the screw feeder 6 and the vibration feeder 
7, and then an appropriate amount of the friction material 2 is charged 
into the cavity 8a of the intermediate die member 8 in a heaped-up manner. 
The intermediate die member 8 thus supplied with the friction material 2 is 
transferred by the conveyer 30 together with the transfer device 31, and 
reaches a position beneath the leveling device 10. Then, the first 
elevator mechanism 13 is driven to move the base 11 downward, so that the 
plurality of narrow bars 12 are inserted into the cavity 8a of the 
intermediate die member 8, thereby causing the lower end portions of the 
narrow bars 12 to be extended into the heaped-up friction material 2. 
Then, the horizontal movement-imparting mechanism 14 is driven to impart a 
horizontal reciprocal movement to the base 11. As a result, the friction 
material 2 heaped up on the lower die member 9 is raked in right and left 
directions by the plurality of narrow bars 12, and therefore is generally 
leveled, that is, made generally flat. After this leveling operation is 
finished, the base 11 is returned or moved upward by the first elevator 
mechanism 13 to the position where the narrow bars 12 will not interfere 
with the intermediate die member 8. 
The intermediate die member 8 is further transferred by the conveyer 30 to 
a position beneath the recess-pressing device 15. Then, the second 
elevator mechanism 17 is driven to move the pair of push rods 22 downward 
into the cavity 8a of the intermediate die member 8, so that the pair of 
push rods 22 are pushed into the pair of recesses 9a in the lower die 
member 9, respectively. As a result, part of the generally 
leveled-friction material 2 is pressed or forced into the pair of recesses 
9a, and therefore each recess 9a is fully filled with the friction 
material, and the friction material in each recess 9a undergoes a suitable 
compressive force. After the friction material is pressed into the pair of 
recesses 9a, the push rods 22 are returned or moved upward by the second 
elevator mechanism 17 to the position where the push rods 22 will not 
interfere with the intermediate die member 8. 
Then, the intermediate die member 8 is further transferred by the conveyer 
30 to a position beneath the pressing device 18. Then, the third elevator 
mechanism 21 is driven to move the support member 20 downward, so that the 
upper die member 23 is fitted into the cavity 8a of the intermediate die 
member 8 and is moved downward. As a result, the friction material 2 
within the intermediate die member 8 is pressed by the upper die member 23 
and is preformed into a predetermined shape to provide the preformed 
friction material 2 for use in the disc brake. 
Then, the lower die member 9 is pushed or ejected upward to remove the 
preformed friction material 2 from the intermediate die member 8. Then, 
the preformed friction material is transferred to the next stage, that is, 
a heat shaping step. 
In the above embodiment, although the intermediate die member 8 has a 
tubular shape having the cavity 8a for receiving the lower die member 9, 
this intermediate die member 8A may be replaced by a modified intermediate 
die member (shown in FIG. 7) which comprises a body in the form of a block 
having a plurality of tubular cavities 8A' in which lower dies 9A are 
received, respectively. In this case, of course, the narrow bars 12 of the 
leveling device 10, the push rods 22 of the recess-pressing device 15 and 
the upper die 23 are provided for a respective one of the cavities 8A'. 
With the use of the intermediate die member 8A, a plurality of friction 
materials 2 can be produced at the same time. 
As will be appreciated from the foregoing description, in the present 
invention, the preformed friction material can be automatically produced 
by the preforming apparatus, and the efficiency of the operation is 
greatly improved, without varying the quality of the preformed products. 
Further, since the operator does not need to directly touch the friction 
material containing harmful asbestos, the working environment is greatly 
improved.