JP2009220160A - Manufacturing method of caliper body of disk brake for vehicle, and caliper body - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a manufacturing method of a caliper body of a disk brake for a vehicle capable of casting the caliper body without using any shell core, and easily performing process of shake-out and finishing in a short time, and the caliper body. <P>SOLUTION: The manufacturing method of the caliper body of the monocoque structure opposed piston disk brake for the vehicle includes a core manufacturing step of manufacturing a metallic hollow core 21, a caliper body casting step of casting the caliper body 3 by arranging the hollow core 21 in a casting mold 20 of the caliper body 3, and a finishing step of performing the finishing while leaving the hollow core 21 in the cast caliper body 3. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a caliper body manufacturing method and a caliper body for a disc brake for a vehicle, and more specifically, a pair of action portions arranged to face each other with a disc rotor interposed therebetween and a bridge portion straddling the outside of the disc rotor are integrally formed. The present invention relates to a caliper body manufacturing method and a caliper body for a monocoque piston facing type vehicle disc brake.

Conventionally, in a caliper body in which a pair of action portions arranged opposite to each other with a disc rotor interposed therebetween and a bridge portion straddling the outside of the disc rotor are integrally formed by a casting mold, the caliper body is surrounded by the cylinder hole, the action portion, and the bridge portion. The opening is formed by a core during casting. As the core, normally, a shell core in which silica sand (shell sand) coated with resin is hardened by heat is used, and the caliper body has the shell core disposed in the casting mold, and the casting mold and the shell. For example, a molten metal such as an aluminum alloy is injected into a cavity defined between the core and the core. Then, the mold is released after cooling, and the caliper body is manufactured by finishing after removing the shell core (see, for example, Patent Document 1).
JP 2005-163810 A

  However, as described above, when a shell core is used as the core, sand dropping may occur and the appearance of the product may be impaired, and if the removal of the shell sand after releasing the mold is insufficient, Sand may fall into the heat treatment furnace, and it may take time to remove the shell sand, resulting in poor yield. In addition, blade spillage may occur on the processing blade during finishing.

  Therefore, the present invention provides a caliper body manufacturing method for a vehicle disc brake that can cast a caliper body without using a shell core directly in a product manufacturing process, and can perform a mold releasing and finishing process easily and in a short time. The purpose is to provide a caliper body.

  In order to achieve the above object, a method of manufacturing a caliper body for a vehicle disc brake according to the present invention is a casting mold in which a pair of action portions arranged opposite to each other with a disc rotor interposed therebetween and a bridge portion straddling the outside of the disc rotor are used. A caliper body of a monocoque piston opposed type disk brake for a vehicle, which is integrally formed, and has a cylinder hole provided in the action part and an opening surrounded by the action part and the bridge part formed by a core at the time of casting In the manufacturing method, a core manufacturing process for manufacturing a metal hollow core, a caliper body casting process for casting the caliper body by placing the hollow core in a caliper body casting mold, and a cast caliper body And a finishing step of performing a finishing process in a state where the hollow core remains in the hollow core, the hollow core includes a core casting mold and It may be cast by injecting a molten metal into a cavity formed between the core for casting the core and the hollow core split after forming a plurality of hollow core split bodies by die casting. It may be formed by joining bodies. Further, it is preferable that the caliper body and the hollow core are each made of aluminum or an aluminum alloy.

  The caliper body of the disc brake for a vehicle according to the present invention is formed by integrally forming a pair of action portions disposed opposite to each other with the disc rotor interposed therebetween and a bridge portion straddling the outer side of the disc rotor by a casting mold. A caliper body of a monocoque piston opposed type disk brake for a vehicle, in which a cylinder hole formed in a cylinder and an opening surrounded by the action part and the bridge part are formed by a core at the time of casting. The hollow hole is used to form a pilot hole in the cylinder hole, and the piston sliding surface in the pilot hole in a state in which the hollow core after casting is left is subjected to finishing processing, The caliper body and the hollow core are preferably made of aluminum or an aluminum alloy, respectively.

  According to the caliper body manufacturing method and caliper body for a vehicle disc brake of the present invention, a metal hollow core is used as the core, so that no sand is dropped during caliper body casting, and the shell is installed in the heat treatment furnace. There is no risk of sand falling. Further, the shell sand does not adhere to the cast product, and the appearance defect can be prevented, and the blade shell does not occur due to the adhered shell sand during the finishing process.

  For metal hollow cores that use shell cores, the hollow core can be formed at low cost, and the sand of the shell core is completely removed from the cast hollow core before caliper body casting. Since it can be applied as a core, shell sand does not fall into a casting mold for caliper body casting, and shell sand does not adhere to a cast product.

  When a metal hollow core is formed by die casting, it is possible to form a core with better dimensional accuracy than that formed using a shell core, thus reducing the time required for finishing. Can do.

  Further, by manufacturing the caliper body and the hollow core with aluminum or an aluminum alloy, the caliper body can be reduced in weight, and the hollow core can be easily cast.

  1 to 8 are views showing a vehicle disc brake according to an embodiment of the present invention. FIG. 1 is a sectional view taken along the line II in FIG. 5, FIG. 2 is a sectional view taken along the line II-II in FIG. FIG. 4 is an explanatory diagram during caliper body casting, FIG. 5 is a front view of the disc brake, FIG. 6 is a sectional view taken along VI-VI in FIG. 7, FIG. 7 is a plan view of the disc brake, and FIG. It is a perspective view of a brake.

  The disc brake 1 is integrally formed by casting a pair of action portions 3a and 3b that are opposed to each other with a disc rotor 2 that rotates in the direction of arrow A together with the wheels when the vehicle moves forward together with a bridge portion 3c that straddles the outer periphery of the disc rotor 2. The caliper body 3 having a monocoque structure is provided, and an opening 3d surrounded by the action portions 3a and 3b and the bridge portion 3c is provided on the outer periphery side of the disc rotor of the caliper body 3.

  Each operating portion 3a, 3b is provided with two cylinder holes 4 opened on the disk rotor 2 side so as to face each other. In each cylinder hole 4, a piston 5 is accommodated via a piston seal 6 and a dust seal 7, and is formed in a four-pot piston facing type, and the bottom of each cylinder hole 4 and the bottom surface of each piston 5 are formed. In the meantime, hydraulic chambers 8 to which hydraulic fluid is supplied are respectively defined.

  The cylinder hole 4 is continuously formed with a large-diameter portion 4a on the bottom side and a small-diameter portion 4b on the opening side, and a friction pad 9 composed of a lining 9a and a back plate 9b is sandwiched between the disk rotor 2 on the opening side. They are arranged opposite to each other. The friction pad 9 has a back plate 9b suspended by a hanger pin 10 that spans the outer periphery of the disk rotor and extends in the disk axial direction across the opening 3d, and is provided on the disk inlet side and the outlet side, respectively. It is movable between the torque receiving portions 3e and 3f in the disk axis direction.

  On the disk insertion side and the extraction side of one working part 3a, there are provided mounting bolt insertion holes 3g, 3g in the radial direction of the disk, and the mounting bolts inserted through the mounting bolt insertion holes 3g, 3g are connected to the vehicle body side. The caliper body 3 is attached to the vehicle body by being screwed to the caliper attaching portion provided on the body.

  In each action part 3a, 3b, the fluid pressure chamber side communication parts 11, 11 for communicating adjacent fluid pressure chambers 8 are provided. Further, on the disk brake delivery side of the caliper body 3, the first fluid passage hole 12 is provided from the one action part 3a toward the fluid pressure chamber 8 on the disk brake delivery side of the other action part 3a. Second fluid passage holes 13 are respectively drilled from the portion 3a toward the fluid pressure chamber 8 on the disk brake delivery side of the one action portion 3a, and the first fluid passage hole 12 and the second fluid passage hole 13 are connected to each other. Crossed. A union hole 3h is formed in the outer surface opening of the first liquid passage hole 12, a bleeder hole is formed in the second liquid passage hole 13, a union bolt of a brake hose is formed in the union hole 3h, and a brewer is formed in the bleeder hole. Each screw 14 is screwed.

  When such a caliper body 3 is manufactured by casting, a known metal casting mold 20 having an upper mold 20a and a lower mold 20b that form the outer shape of the caliper body, and a disk insertion of the caliper body 3 are provided. A metal hollow core 21 disposed in the portion forming the opening 3d including the torque receiving portions 3e and 3f provided on the side and the disk delivery side and the portion forming the cylinder hole 4 is used. .

  The hollow core 21 of this embodiment is manufactured by a core manufacturing process. For example, as shown in FIG. 3, it can be manufactured by casting using a core casting mold 22 and a core core 23 for core casting. The core core 23 for core casting is formed by a well-known method. For example, after blowing shell sand into a mold for core molding corresponding to the outer shape of the core core 23 for core casting, It is obtained by taking it out from the mold. The core casting mold 22 includes an upper mold 22a and a lower mold 22b in which a core core 23 for core casting is disposed. The upper mold 22a, the lower mold 22b, and a core core 23 for core casting. A hollow core 21 made of aluminum is cast by injecting a metal, for example, a molten metal of aluminum (including an aluminum alloy, the same applies hereinafter) into the cavity 24 formed between the two. Next, the shell sand in the hollow core 21 which has been released from the mold is cast out from the opening 21a formed in the hollow core 21 using a known sand removing device, and the shell sand is discharged from the hollow core 21. Is completely removed. Further, heat treatment is performed in a heat treatment furnace as necessary.

  Next, the caliper body is cast by a caliper body casting process. As shown in FIG. 4, the hollow core 21 supported by a mold member 20c is disposed between the upper mold 20a and the lower mold 20b of the casting mold 20 forming the outer shape of the caliper body 3, and the upper mold A molten aluminum of the same type as that of the hollow core 21 is injected into a cavity 25 formed between the hollow core 21 and the lower mold 20b and the mold member 20c.

  Since the molten aluminum injected into the cavity 25 is the same kind of aluminum as the hollow core 21, the surface of the hollow core 21 in contact with the molten metal melts and is cooled and cast in an integrated state with the molten metal. The prototype of the caliper body 3 is in a state where the main body portion of the caliper body 3 and the prepared hole portion of the cylinder hole 4 and the opening 3d portion of the hollow core 21 are integrated.

  The prototype of the caliper body 3 thus cast is subjected to a predetermined heat treatment in a heat treatment furnace, and then the small diameter portion of the cylinder hole 4 in which the piston 5 slides with respect to the pilot hole portion of the cylinder hole 4. 4b and the piston seal groove 4c in which the piston seal 6 is fitted and the dust seal groove 4d in which the dust seal 7 is fitted are respectively finished by a predetermined machining blade or the like. Similarly, a predetermined finishing process is performed on the rotor groove 3i, the torque receiving portions 3e, 3f, and the like.

  At this time, the portion corresponding to the large diameter portion 4 a in the pilot hole portion of the cylinder hole 4 corresponds to the large diameter portion 4 a by making the inner diameter of this portion of the hollow core 21 larger than the outer diameter of the piston 5. The finishing process can be omitted, and the surface of the hollow core 21 can be left as shown in FIGS. 1 and 2. As described above, the portion corresponding to the large diameter portion 4a is not in contact with the outer peripheral surface of the piston 5 and the surface of the hollow core 21 even when the surface of the hollow core 21 is left. There is no risk of impairing the slidability. Further, on the disk rotor side surface of the bridge portion 3c and the like, the surface of the hollow core 21 is left without finishing by appropriately setting the shape and dimensions of the corresponding hollow core 21 portion. State. Conventionally, in the pilot hole portion of the cylinder hole 4, in consideration of the draft angle of the core and the sand removability, it is necessary to form the inner part of the cylinder hole 4 with a smaller diameter than the opening side. In addition, by using the hollow core 21 made of metal, the molten metal and the hollow core 21 are integrated during casting, and the cast product in a state where the hollow core 21 is left without being extracted is referred to as a prototype of the caliper body 3. By doing so, since the inner part of the cylinder hole 4 can be formed with a larger diameter than the opening side, finishing of this part can be omitted.

  Further, the caliper body 3 described above is manufactured by forming the fluid pressure chamber side communication portion 11, the liquid passage holes 12, 13, and the like. Since the caliper body 3 of the present embodiment is manufactured using the metal hollow core 21 without using the shell core made of shell sand as described above, the caliper body using the shell core is used. When casting the caliper body, the sand does not fall off, and the shell sand can be prevented from adhering to the casting and causing defects such as poor appearance. The processing blade or the like is not spilled by the adhered shell sand. Further, there is no risk that shell sand will fall into the heat treatment furnace.

  Further, since the hollow core 21 is formed using the shell core, the hollow core 21 can be formed at low cost, and after the sand of the shell core is completely removed from the cast hollow core, the caliper body is cast. Since it is used as a core, shell sand does not fall into the casting mold 20 for caliper body casting, and shell sand does not adhere to the cast product.

  Further, by manufacturing the caliper body 3 and the hollow core 21 with the same kind of aluminum, the caliper body can be reduced in weight, and the hollow core 21 can be easily cast.

  The present invention is not limited to the above-described embodiments, and the hollow core is formed by dividing a plurality of hollow cores, for example, a hollow core into two halves and forming each half by die casting. It may be manufactured by joining the halves. In the case of manufacturing by die casting as described above, since a core with higher dimensional accuracy than that formed using a shell core can be formed, the time required for finishing can be further shortened.

  The caliper body and the hollow core are not limited to those made of aluminum or an aluminum alloy, but the melting temperature of the metal forming the hollow core is equal to or higher than the melting temperature of the metal forming the caliper body. If so, other metals can be used.

  Furthermore, the present invention is not limited to a 4-pot opposed caliper body, and can be applied to a 2-pot or 6-pot or larger opposed caliper body.

It is II sectional drawing of FIG. It is II-II sectional drawing of FIG. It is explanatory drawing at the time of core casting which shows one example of this invention. It is explanatory drawing similarly at the time of caliper body casting. It is a front view of the disk brake for vehicles similarly. It is VI-VI sectional drawing of FIG. It is a top view of the disk brake for vehicles similarly. It is a perspective view of a disk brake for vehicles similarly.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Disc brake, 2 ... Disc rotor, 3 ... Caliper body, 3a ... Action part, 3b ... Action part, 3c ... Bridge part, 3d ... Opening part, 3e, 3f ... Torque receiving part, 3g ... Mounting bolt insertion hole, 3h ... Union hole, 3i ... Rotor groove, 4 ... Cylinder hole, 4a ... Large diameter part, 4b ... Small diameter part, 4c ... Piston seal groove, 4d ... Dust seal groove, 5 ... Piston, 6 ... Piston seal, 7 ... Dust seal, DESCRIPTION OF SYMBOLS 8 ... Fluid pressure chamber, 9 ... Friction pad, 9a ... Lining, 9b ... Back plate, 10 ... Hanger pin, 11 ... Fluid pressure chamber side communication part, 12 ... 1st fluid passage hole, 13 ... 2nd fluid passage hole, 14 ... Bruder screw, 20 ... casting mold, 20a ... upper mold, 20b ... lower mold, 20c ... mold member, 21 ... hollow core, 21a ... opening, 22 ... core casting mold, 22a ... upper mold, 22b ... Lower mold, 23 ... Core casting shell Child, 24, 25 ... cavity

Claims (6)

A pair of working parts arranged opposite to each other across the disk rotor and a bridge part straddling the outside of the disk rotor are integrally formed with a casting mold, and a cylinder hole provided in the working part, and the working part and the bridge part In a caliper body manufacturing method for a monocoque piston-opposed vehicle disc brake for a vehicle, which forms an enclosed opening with a core at the time of casting, a core manufacturing process for manufacturing a metal hollow core, and a caliper body A caliper body casting step of casting the caliper body by disposing the hollow core in a casting mold, and a finishing step of performing a finishing process with the hollow core left in the cast caliper body. A caliper body manufacturing method for a disc brake for a vehicle. 2. The vehicle disc brake according to claim 1, wherein the hollow core is cast by injecting molten metal into a cavity formed between a core casting mold and a core core for casting the core. Caliper body manufacturing method. The caliper for a vehicle disc brake according to claim 1, wherein the hollow core is formed by forming a plurality of hollow core segments by die casting and then joining the hollow core segments. Body manufacturing method. The caliper body manufacturing method for a vehicle disc brake according to any one of claims 1 to 3, wherein the caliper body and the hollow core are each made of aluminum or an aluminum alloy. A pair of working parts arranged opposite to each other across the disk rotor and a bridge part straddling the outside of the disk rotor are integrally formed with a casting mold, and a cylinder hole provided in the working part, and the working part and the bridge part In the caliper body of a monocoque piston-facing disk brake for a vehicle, which forms an enclosed opening with a core at the time of casting, the pilot hole of the cylinder hole is formed by using a metal hollow core at the time of caliper body casting. A caliper body for a disk brake for a vehicle, wherein the piston sliding surface in the prepared hole in a state of leaving the hollow core after casting is finished. 6. The caliper body for a vehicle disc brake according to claim 5, wherein the caliper body and the hollow core are each made of aluminum or an aluminum alloy.

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