Abstract:
The present invention provides an improved multi-mold apparatus for manufacturing friction members, with each mold composed of a set comprising a first (top) mold, a second (bottom) mold, and a frame mold. The apparatus is capable of correcting any misalignment in the mountings of the plurality of molds and accurately aligning the molds by movably supporting at least one of the first mold, the second mold and the third mold by first, second and frame bases, respectively, so that the base and molds are movable laterally, in a direction perpendicular to the direction of advance. Projections are formed on one of the first mold and either the frame mold or the back plate and bonding through-holes are formed on the remaining mold or the back plate, so that the projections engage the holes so as to align the first mold and the frame mold accurately.

Description:
CLAIM OF PRIORITY 
   This application claims priority from Japanese Patent Application No. 2003-271227, entitled “Friction Member Manufacturing Apparatus” filed on Jul. 7, 2003, the entire contents of which are incorporated herein by reference. 
   FIELD OF THE INVENTION 
   The present invention relates to an improved friction member manufacturing apparatus for manufacturing friction member used in a vehicle brake assembly, and more particularly, to a friction member manufacturing apparatus that is multi-mold so as to mold multiple friction members at once. 
   BACKGROUND OF THE INVENTION 
   A friction member for a vehicle brake assembly is formed by affixing friction material manufactured from a raw material mixture of fiber, filler and a binder to a steel back plate. However, simply attaching the friction material to just one side of the back plate does not provide the friction member with adequate adhesive strength. As a result, one or more bonding through-holes are formed in the back plate and the friction material is forced into the bonding through-holes at the same time as friction material is affixed to one side of the back plate, in order to increase the strength of the attachment by contacting the friction material against the insides of the bonding through-holes. 
     FIGS. 7A and 7B  are diagrams showing a conventional friction member back plate, with  FIG. 7A  showing a plan view and  FIG. 7B  showing a lateral cross-sectional view along a line VII—VII. The friction member is used as the disk pad of a disk brake. A back plate  1  shown in the diagram is formed by using a press to stamp automobile sheet metal or machine tool sheet metal to a predetermined shape and simultaneously forming two bonding through-holes  2 ,  2 , in the back plate  1 . 
   After being stamped by the press, the back plate  1  is subjected to an oil-removal process that removes oil from the surface of the back plate  1 . The surface is then finished by sand-blasting, after which it is coated with a thermosetting binder in order to increase the strength of the attachment to the friction material. 
   The raw material of the friction material is, as described above, a mixture of fiber, filler and a binder. The fiber used is either organic fiber, such as cellulose or aramid fibers, metal fiber made from chips of metal or steel, or inorganic fiber such as rock fiber. The filler is there to provide volume and lubrication, in order to obtain stable friction, and may, for example, be barium sulfate, calcium carbonate or graphite. A thermosetting resin, which may be phenol resin or urea resin, is used for the binder, which binds the fiber and filler together. 
   The raw material of the friction material, once the ingredients have been mixed together, is then weighed to a predetermined weight, put into a metal mold, not shown, compressed, and formed into a semi-finished product. At this point, the friction material, which in principal is formed only by compression, is not baked but in some cases might be heated to a temperature range within which the binder does not react. It should be noted that the friction member of the present invention includes the aforementioned semi-finished product as well. 
     FIGS. 8A and 8B  are diagrams showing the friction material as a semi-finished product provisionally formed as described above, in which  FIG. 8A  shows a plan view of the semi-finished product and  FIG. 8B  shows a front view of the semi-finished product. The semi-finished product  3 , although shaped like the final product, is not dense, and has a thickness T that is approximately twice that of a thickness t (shown in  FIG. 10 ) of the final product pressed onto the back plate  1  and compressed to a predetermined density. In addition, convex portions  4 ,  4  corresponding to the bonding through-holes  2 , 2  described above are formed on the semi-finished product  3 . The convex portions  4 ,  4  are broad at a base but narrow toward a tip to a diameter d1 that is smaller than a diameter D 1  (in  FIG. 7 ) of each of the bonding through-holes  2 ,  2 , so that the convex portions  4 ,  4  can be fitted easily into the bonding through-holes  2 ,  2 . 
   When the back plate  1  and the semi-finished friction material product  3  are attached to each other as described above, they are sent to the press shown in  FIG. 9 . The press is a multi-mold type, with a plurality of sets of molds, each formed by an arrangement consisting of a top mold  5  and a corresponding frame mold  6  and a bottom mold  7 , all disposed on a single surface. 
   A vertically traverse space  6   a  is formed in the frame mold  6 , with the bottom mold  7 , which in cross-section is identical to the cross-section of the space  6   a  of the frame mold  6 , entering from below the space  6   a  to form the bottom of the space  6   a , in which the semi-finished product  3  is contained. In the event that the semi-finished product  3  is not used, powdered friction raw material is inserted instead. The bottom mold  7  can be raised and lowered within the space  6   a . The top mold  5  can be contacted with and separated from the frame mold  6 . 
   A plurality of top molds  5  are mounted at predetermined intervals on a top mold base  15 , with a plurality of frame molds  6  corresponding to the top molds  5  mounted on a frame mold base  16 , and bottom molds  7 , slidably inserted into the frame molds  6 , mounted on a bottom mold base  17 . The entire assembly is configured so that the top mold base  15  can descend and the bottom mold base  17  can ascend within the frame mold  6 . 
   A plurality of alignment pins  6   b  for positioning the back plate  1  are provided on a top surface of the frame mold  6 . Two projections  8  corresponding to the two bonding through-holes  2  are provided on a bottom surface of the top mold  5 . The two projections  8  are cylinders having a height less than a thickness of the back plate  1  and a diameter D 2  less than a diameter D 1  of the bonding through-holes  2 . 
   The multi-mold construction of the press shown in  FIG. 9  greatly improves productivity. Moreover, the top mold  5 , frame mold  6  and bottom mold  7  are detachably mounted on the bases  15 ,  16  and  17 , respectively, and thus can be replaced with other molds. Such a configuration makes it possible to switch easily between the manufacture of friction members of various different shapes. 
   Next, a description is given of a method of manufacturing the friction member using the manufacturing apparatus shown in  FIG. 9 . 
   First, as shown in  FIG. 9 , the semi-finished product  3  is placed on the bottom mold  7  within the frame mold  6 , with the back plate  1  placed on the frame mold  6 . Where the semi-finished product  3  is not used, powdered friction raw material is placed inside the frame mold  6 , with the back plate  1  placed on top of the raw material and the alignment pins  6   b  aligning the back plate  1 . Thereafter, the top mold  5  descends, the two projections  8  enter the two bonding through-holes  2 ,  2  from above and the back plate  1  is pressed against the frame mold  6 . At the same time, the bottom mold  7  ascends and the convex portions  4 ,  4  corresponding to the bonding through-holes  2 ,  2 , or the powdered friction raw material, as the case may be, enter the bonding through-holes  2 ,  2 , and the back plate  1  and the semi-finished product  3  overlap and are compressed and heated. 
     FIG. 10  is a diagram showing a state in which the press has completed compression and heating. As shown in the diagram, the friction material semi-finished product  3 , in which the binder material has reacted due to the heat, has been compressed and become denser, with a thickness T halved to a new thickness t, to form a friction material  9  of a predetermined thickness that is attached to the back plate  1 . Further, the convex portions  4 ,  4  inside the bonding through-holes  2 ,  2  are pressed down from the top by the projections  8 ,  8  formed in the top mold  5  and spread out within the bonding through-holes  2 ,  2  so as to adhere tightly to the inner walls of the bonding through-holes  2 ,  2 . 
     FIGS. 11A and 11B  are diagrams showing a plan view and a lateral cross-sectional view, respectively, along a line XI—XI of a friction member formed according to the present invention. A friction material  9  is bonded both to a bottom surface of the back plate and inside surface of the bonding through-holes  2 ,  2 , and increase the strengh of the attachment. 
   However, in the conventional art described above, the diameter D 2  of the cylindrical projections  8 ,  8  on the top mold  5  must be substantially smaller than the diameter D 1  of the bonding through-holes  2 ,  2 . In other words, because of the multi-mold construction of the press as described above, cumulative error occurs when mounting a plurality of molds, and as a result the accuracy with which the projections  8 ,  8  and the bonding through-holes  2 ,  2  are aligned cannot be improved. As the diameter D 2  of the projections  8 ,  8  approaches the diameter D 1 , the projections  8 ,  8  become unable to enter the bonding through-holes  2 ,  2  and instead sink into the peripheral areas thereof, which in turn makes separation after formation difficult. 
   As a multi-mold technique, a method that is described in Japanese Laid-Open Patent Publication No. 2000-27914 is known. This method involves arranging an even number of back plates symmetrically about a line in a single integrated back plate assemblage, pressing a similar integrated assemblage of friction material onto the back plate assemblage, and then cutting into a plurality of friction members. 
   However, the above-described method handles the back plate as an assemblage of multiple back plates formed into a single integrated structure, and therefore the problem of back plate relative positional error does not arise. Accordingly, no mention is made of the problem of the projections  8 ,  8  becoming unable to enter the bonding through-holes  2 ,  2  and instead sinking into the peripheral areas thereof and making separation after formation difficult when affixing friction material to a plurality of back plates. 
   BRIEF SUMMARY OF THE INVENTION 
   The present invention is conceived in light of the foregoing drawback of the conventional art, and has as an object to provide an improved friction member manufacturing apparatus of multi-mold construction that is provided with a plurality of sets of molds to affix friction material to a plurality of back plates simultaneously and that corrects errors in the positioning of each of the molds that comprise the plurality of mold sets so as to provide accurate mold positioning. 
   According to a first aspect of the present invention, the foregoing object is attained by providing a friction member manufacturing apparatus comprising: 
   a frame mold, having a space for containing friction material, the space penetrating the frame mold; 
   a first mold, disposed on one side of the space in the frame mold and moving relative to the frame mold so as to separably contact the frame mold, either directly or via an intermediate member; and 
   a second mold, disposed on a side of the space in the frame mold opposite the side on which the first mold is disposed so as to enclose the space, the second mold capable of moving relative to the frame mold, in such a way as to enter and exit an interior of the frame mold; 
   a first mold base for supporting a plurality of first molds; 
   a frame mold base for supporting a plurality of frame molds; and 
   a second mold base for supporting a plurality of second molds, 
   at least one of the mold bases, and the molds supported by the at least one of the bases, supported in a state in which the base and the molds the base supports are movable in a direction perpendicular to a direction in which the second mold enters and exits the interior of the frame mold, 
   a convex portion formed on either the first mold and the frame mold or intermediate member, and a concave portion formed on another side, 
   the convex portion and the concave portion engaging each other so as to align the first mold and the frame mold with each other. 
   According to a second aspect of the present invention, the foregoing object is also attained by providing a friction member manufacturing apparatus as described above, wherein at least one of the convex portion and the concave portion is provided with guide surface for guiding the other portion. 
   According to a third aspect of the present invention, the foregoing object is also attained by providing a friction member manufacturing apparatus as described above, wherein at least one base and the molds supported by the base are the first mold base and the first mold. 
   According to a fourth aspect of the present invention, the foregoing object is also attained by providing a friction member manufacturing apparatus as described above, wherein at least one base and the molds supported by the base are the frame mold base and the frame mold, and the second mold base and the second mold. 
   According to a fifth aspect of the present invention, the foregoing object is also attained by providing a friction member manufacturing apparatus as described above, wherein the friction member is a friction material affixed to a back plate, the intermediate member is the back plate of the friction member, the concave portion is a bonding through-hole formed in the back plate and the convex portion is a projection that enters the bonding through-hole formed in the first mold. 
   According to a sixth aspect of the present invention, the foregoing object is also attained by providing a friction member manufacturing apparatus as described above, wherein, the projection has a guide surface provided on at least one of a base portion or a tip portion thereof. 
   A plurality of first molds are mounted on the first mold base, a plurality of frame molds are mounted on the frame mold base, and a plurality of second molds are mounted on the second mold base. The first mold separably contacts the frame mold either directly or through an intermediate member. 
   In a multi-mold configuration like that described above, when a plurality of molds is mounted on a single mold base, errors in mounting position arise. It can happen that such mounting position errors accumulate, until the gap between one mold and its opposing pair grows large, with the result that the manufactured friction member can be defective and the molds can bite into each other, causing the manufacturing apparatus to break down. 
   According to the present invention, for example, the first mold is mounted so as to be movable with respect to the first mold base. If there is a gap between the mounting positions of the first mold and the corresponding to frame molds and second molds, a convex portion formed on either the first mold and the frame mold or an intermediate member and a concave portion formed on the remaining member engage each other, thus moving the first mold and enabling the first mold to be guided to the correct position. 
   Alternatively, instead of mounting the first mold so as to be movable with respect to the first mold base, the frame mold may be mounted so as to be movable with respect to the frame mold base, or, further, the second mold may be mounted so as to be movable with respect to the second mold base, and achieve the same effect. 
   According to the friction member manufacturing apparatus of the present invention, by mounting at least one of the base and the molds supported thereon so that the base and molds are movable laterally, in a direction perpendicular to the direction of advance, and forming convex portion on either the first mold and either the frame mold or the intermediate member, and forming concave portion on another side, so that the convex portion engage concave portion and align the first mold and the frame mold, any error in mounting position, that is, misalignment, of the first and second molds and the frame mold that together form each of the plurality of molds in the multi-mold configuration can be corrected, and the molds can be aligned by the movable molds moving when the convex portion and concave portion engage. 
   The friction member is formed by affixing friction material to the back plate, with the friction member back plate being the intermediate member described above. The back plate has bonding through-holes as the above-described concave portions, and projections that enter and engage the bonding through-holes as the above-described convex portions are provided on the first mold. As a result of such a configuration, misalignment between the molds can be prevented. 
   Providing guide surfaces on the tips of the projections enables the projections to engage the bonding through-holes easily even if the projections and holes are misaligned. Providing guide surfaces on the bases of the projections enables the projections to be centered easily within the bonding through-holes. 
   Other features, objects and advantages of the present invention will be apparent from the following description when taken in conjunction with the accompanying drawings, in which like reference characters designate identical or similar parts throughout the figures thereof. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
     The accompanying drawings, which are incorporated in and constitute apart of the specification, illustrate embodiments of the invention and, together with the description, serve to explain the principles of the invention. 
       FIG. 1  is a diagram showing a front cross-sectional view of the main parts of a friction member manufacturing apparatus of the present invention; 
       FIG. 2  is a diagram showing an enlarged cross-sectional view of a portion at which a first mold is supported by a first mold base; 
       FIG. 3  is a diagram showing an enlarged lateral cross-sectional view of a first mold projections and a bonding through-hole; 
       FIGS. 4A and 4B  are diagrams showing an enlarged top view of a bonding through-hole after a friction material is affixed to a back plate, in which  FIG. 4A  shows the outline of the projection askew and  FIG. 4B  shows the outline of the projection centered, 
       FIG. 5  is a diagram showing a cross-sectional view of a joint portion according to a second embodiment of the present invention, where a first mold and a first mold base are joined; 
       FIG. 6  is a diagram showing a cross-sectional view of a joint portion according to a third embodiment of the present invention, where a frame mold and a second mold portion are connected to each other; 
       FIGS. 7A and 7B  are diagrams showing a conventional friction member back plate, with  FIG. 7A  showing a plan view and  FIG. 7B  showing a lateral cross-sectional view along a line VII—VII; 
       FIGS. 8A and 8B  are diagrams showing the friction material as a semi-finished product provisionally formed, in which  FIG. 8A  shows a plan view of the semi-finished product and  FIG. 8B  shows a front view of the semi-finished product; 
       FIG. 9  is a diagram showing a cross-sectional view of the essential parts of a conventional friction member manufacturing apparatus; 
       FIG. 10  is a diagram showing a state in which a press shown in  FIG. 9  has completed compression and heating; and 
       FIGS. 11A and 11B  are diagrams showing a plan view and a lateral cross-sectional view, respectively, along a line XI—XI of a friction member formed according to the present invention. 
   

   DETAILED DESCRIPTION OF THE INVENTION 
   Preferred embodiments of the present invention are now described in detail in accordance with the accompanying drawings. 
     FIG. 1  is a diagram showing a front cross-sectional view of the main parts of a friction member manufacturing apparatus of the present invention. 
   The basic structure of the manufacturing apparatus shown in  FIG. 1  is the same as that of the conventional apparatus described above. In other words, a first mold  105 , which is a top mold, has a projection  108  as a convex portion. A frame mold  106  is provided with a space  106   a  formed so as to completely penetrate the frame mold  106  vertically. A second mold  107 , which is a bottom mold, is the same shape as the space  106   a , and is inserted into the space  106   a  from below the space  106   a  to form a bottom surface for the space  106   a , allowing powdered friction raw material  103  or a semi-finished product  3  to be inserted into the space  106   a.    
   The first mold  105  is supported by a first mold base  115 , the frame mold  106  is mounted on a frame mold base  116 , and the second mold  107  is mounted on a second mold base  117  so as to be enter and exit an interior of the frame mold  106 . 
   As with the conventional art, alignment pins  109  are provided on a top surface of the frame mold  106 . Similarly, the back plate  1 , too, as with the conventional art, has a plurality of bonding through-holes  2 ,  2  as concave portions. In the present embodiment, the distinctive feature is that the first mold base  115  supports the first mold  105 . 
     FIG. 2  is a diagram showing an enlarged cross-sectional view of a portion at which the first mold  105  is supported by the first mold base  115 . The first mold support has at least two mounting holes  115   a  for every first mold  105 . The mounting hole  115   a  is a stepped aperture, with a wide portion  115   b  and a narrow portion  115   c . The wide portion  115   b  is larger than a head  126   a  of a mounting bolt  126  by a dimension γ on a side, with the narrow portion  115   c  of the mounting hole  115   a  by a same dimension γ on a side. The mounting bolt  126  may, for example, be a bolt with a square hole or a hexagonal hole. 
   A female screw hole  105   a  is formed in the first mold  105 . The narrow portion  115   c  of the mounting hole  115   a  and the female screw hole  105   a  are vertically aligned, the mounting bolt  126  is inserted through the wide portion  115   b  and through the first mold base  115  so as to engage the female screw hole  105   a  formed in the first mold. Then, when the tip of the mounting bolt  126  is tightened so as to contact the bottom surface  105   b  of the female screw hole  105   a , so that a space δ remains between the underside of the head  126   a  of the mounting bolt  126  and the bottom surface of the wide part  115   b  of the mounting hole  115   a . In addition, an interval between adjacent frame molds  106  is at least 4γ. With such a structure, the first mold  105  is able to move slightly laterally (in  FIG. 2 ) by an amount γ with respect to the first mold base  115 . In other words, even if the first mold  105  is out of position with respect to the frame mold  106 , so long as the misalignment is within 2γ, the projection  108  can be inserted into the bonding through-hole  2  by moving the first mold  105 . 
     FIG. 3  is a diagram showing an enlarged cross-sectional view of the projection  108  of the first mold and the bonding through-hole  2 . The tip of the projection  108  is provided with a guide surface  108   a , in which the edge of the tip is rounded off, so that, even with the misalignment between the projection  108  and the bonding through-hole  2  described above, the projection  108  slides easily into the bonding through-hole  2 . Moreover, a similar curved guide surface  108   b  is provided at the base of the projection  108  as well, the guide surface  108   b  widening toward the base. The two guide surfaces  108   a  and  108   b  make it easier to center and insert the projection  108  into the bonding through-hole  102 . 
   The values of the bonding through-hole diameter D 1 , the projection  108  diameter D 2  and the projection  108  base guide surface diameter D 3  are determined by the number of surfaces and the accuracy with which they are positioned. As one example, for illustrative purposes only, if the bonding through-hole  2  diameter is D 1 , then the diameter D 2  of the projection  108  may be 0.1–1.0 mm smaller than D 1 , and the projection base guide surface  108   b  diameter D 3  may be 0.05–1.0 mm larger than D 1 . 
   Next, a description is given of the method of manufacturing the friction member. 
   First, the first mold  105  and the frame mold  106  are separated and the powdered friction raw material  103  is put into the space  106   a  of the frame mold  106 . Alternatively, the semi-finished product  3  described above may be used instead of the powdered friction raw material  103 . 
   Next, the back plate  1  is set on the frame mold  106 . The alignment pins  109  provided on the top surface of the frame mold  106  determine the position of the back plate  1 . 
   In the state described above, the first mold is lowered, forcing the projections  108  into the bonding through-holes  2 . At this time, even if the projections  108  and the bonding through-holes  2  are misaligned, the guide surface  108   a  at the tip of the projections  108  enable the first mold  105  to move laterally within a range of 2γ, thus enabling the misalignment to be corrected. After the projections  108  have entered the bonding through-holes  2 , the first mold  105  is forced against the back plate  1 , which brings the guide surface  108   b  at the base of the projections  108  into force so as to center the projections  108  in the bonding through-holes  2 . The same type of misalignment correction is carried out for all the first molds and frame molds that comprise the multi-mold configuration. 
   Thereafter, the second mold  107  is raised and the friction raw material  103  is compressed and then heated by a heating means not shown, melting and compressing the friction raw material  103  so as to produce a friction member with friction material  9  affixed to the back plate  1  as shown in  FIG. 10 . 
   In the construction described above, the ascent and descent of the first mold  105 , the frame mold  106  and the second mold  107  is not limited, and the movement may be relative. In other words, although in the embodiment described above, the frame mold  106  is fixed in position while the first mold  105  and the second mold  107  are raised and lowered, alternatively, the first mold  105  may be fixed while the frame mold  106  and the second mold  107  are raised and lowered, or the second mold  107  may be fixed while the first mold  105  and the frame mold  106  may be raised and lowered. 
     FIGS. 4A and 4B  are diagrams showing an enlarged top view of a bonding through-hole after a friction material is affixed to a back plate  1 , in which  FIG. 4A  shows an outline of the projection askew and  FIG. 4B  shows the outline of the projection centered. The interior of the bonding through-hole  2  is filled with friction raw material  103  that hardens, but that portion compressed by the projection  108  appears as an impression  108 ′. If there were no guide surface  108   b  on the base of the projection  108  but a perfect right angle instead, the guide surface  108   a  at the tip of the projection  108  would still enable the projection  108  to enter the bonding through-hole  2  but would not be centered, and would instead be biased toward one side of the bonding through-hole  2  like the projection  108 ′ shown in  FIG. 4A . As a result, there is a risk that the friction raw material  103  filling the interior of the bonding through-hole  2  would be compressed with a bias, resulting in inconsistent, or uneven, density. 
   By contrast, according to the embodiments of the present invention, the guide surface  108   b  provided at the base of the projection  108  is curved, so that, when the first mold  105  is pressed against the back plate  1 , as shown in  FIG. 4B , the projection  108  moves automatically to the center of the bonding through-hole  2 , so that the impression  108 ′ laid down in the friction raw material  103  by the projection  108  can be centered. Accordingly, the friction raw material  103  filling the interior of the bonding through-hole  2  is compressed with uniform force over its entire surface, thus enabling the density of the material to be uniform and thereby improving the quality of the finished product. 
   It should be noted that, although the tip edge  108   a  and base edge  108   b , in other words the tip guide surface  108   a  and the base guide surface  108   b , are shown to be arc shaped in cross-section in the embodiment shown in  FIG. 3 , such edge guide surfaces are not limited to the arc shape described above. Therefore, provided that misalignment between the projection  108  and the bonding through-hole  2  is corrected and the projection  108  can be centered in the bonding through-hole  2 , the edge guide surfaces may be any shape, and thus may, for example, be slanted surfaces such as portions of a cone. 
     FIG. 5  is a diagram showing a cross-sectional view of a joint portion according to a second embodiment of the present invention, where a first mold and a first mold base are joined. Retention jigs  115   d  that are L-shaped in cross-section are mounted on the first mold base  115  so as to prevent the first mold  105  from dropping out, by surrounding the first mold  105 . At least some of the retention jigs  115   d  are detachably attached to the first mold base  115  by a bolt or the like. That is, at least some of the retention jigs  115   d  are removable, so that the removable retention jigs  115   d  can be removed to set the first mold  105  in position and the removed retention jigs  115   d  are re-attached to mount the first mold  105  on the first mold base  115 . 
   When the first mold  105  is mounted on the first mold base  115 , a vertical gap δ is formed between the retention jig  115   d  and the bottom of the first mold  105  as shown in  FIG. 5 , and a horizontal gap γ is formed between the side of the first mold  105  and the retention jig  115   d . As a result, the first mold  105  can move freely relative to the first mold base  115  through a range 2γ, and thus the position of the first mold  105  relative to the back plate  1  can be corrected. 
     FIG. 6  is a diagram showing a cross-sectional view of a joint portion according to a third embodiment of the present invention, where a frame mold and a second mold portion are connected to each other. Whereas in the first and second embodiments described above the first mold  105  moves freely with respect to the first mold base  115 , in the third embodiment the frame mold  106  and the second mold  107  move freely. 
   Specifically, holes  106   b  are formed in the bottom of the frame mold  106  and projections  116   a  that enter the holes  106   b  are formed in the top of the frame mold base  116 . The projections  116   a  loosely engage the holes  106   b , securing gaps δ and γ as shown in  FIG. 2 . Additionally, gaps δ and γ may also be retained by providing holes  107   a  in the bottom of the second mold  107  and providing projections  117   a  on the second mold base  117  that engage the holes  107   a  loosely. Such a construction enables the frame mold  106  to move laterally together with the second mold  107  through a range 2γ and enables the projections  108  of the first mold  105  to enter the bonding through-holes  2 . 
   In the embodiments described above, the alignment between the first mold  105  and either the frame mold  106  or the second mold  107  is accomplished by the projections  108  of the first mold  105  as the convex portions engaging the bonding through-holes  2  of the back plate  1  as the concave portions. However, the present invention is not limited to the arrangements thus described. Thus, for example, the alignment pins  109  provided on the frame mold  106  may be made longer than the thickness of the back plate  1  and used as the convex portion projection  108 , in which case the concave portions that are engaged by the alignment pins  109  are formed in the first mold  105 . 
   In addition, all embodiments are configured so that the first mold  105  approaches and withdraws from the frame mold  106  via the back plate  1 . Alternatively, however, the back plate  1  may be set in the space  106   a  so that the first mold  105  and the frame mold  106  contact each other directly. 
   As can be appreciated by those of ordinary skill in the art, although in the above-described embodiments the first mold  105  is the upper mold and the second mold  107  is the lower mold, these assignations may be reversed, with the first mold  105  being the bottom mold and the second mold  107  being the top mold. Further, although the above-described embodiments are used to affix the friction material  9  to the back plate  1 , alternatively, the embodiment may be used as apparatuses for forming semi-finished products  3  from powdered friction raw material  103 . 
   As many apparently widely different embodiments of the present invention can be made without departing from the spirit and scope thereof, it is to be understood that the invention is not limited to the specific embodiments described herein except as defined in the appended claims.