JP5084753B2 - Caliper body manufacturing method and caliper body for disc brake for vehicle - Google Patents

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. In the caliper body, the core is disposed in a casting mold, and a molten metal such as an aluminum alloy is poured into a cavity defined between the casting mold and the core (for example, patent document). 1).

JP 2005-163810 A

  However, normally, the disc brakes attached to the left and right wheels of the vehicle are disc brakes having the same structure, but with a plurality of cylinder holes having different inner diameters in the circumferential direction of the disc, Since the arrangement of the cylinder holes is different between the left side mounting and the right side mounting, a left side mounting core and a right side mounting core are required, which increases costs.

  Accordingly, the present invention provides a caliper body manufacturing method and a caliper body for a vehicle disc brake that can also serve as a core that forms a lower hole of a cylinder hole when casting caliper bodies for left side mounting and right side mounting. It is intended to provide.

In order to achieve the above object, a caliper body manufacturing method for a vehicle disc brake according to the present invention includes a pair of acting portions arranged opposite to each other with a disc rotor interposed therebetween, a bridge portion straddling the outside of the disc rotor, and a disc of one acting portion. A caliper body in which the disk rotor side facing surface of the vehicle body mounting bracket is offset in the disk rotor surface direction from the disk rotor side facing surface of the one working portion. A plurality of cylinder holes with different inner diameters arranged side by side in the disk circumferential direction of the working part and an opening part surrounded by the working part and the bridge part are formed with a core during casting. In addition, a monocoque piston-opposed vehicle disc brake that accommodates pistons having different outer diameters in the plurality of cylinder holes, respectively. In the caliper body manufacturing method, a pilot hole forming portion for forming the plurality of cylinder holes and an opening forming portion for forming the opening are provided, and the pilot hole is formed by sliding the piston. A piston sliding part lower hole forming part that forms a pilot hole of a moving piston sliding part and a large hole part that forms a larger diameter than the piston sliding part on the bottom side of the cylinder hole are formed. A lower diameter hole forming portion, the outer diameter of the piston sliding portion lower hole forming portion is smaller than the piston sliding portion of the smallest diameter cylinder hole in all the cylinder holes, and the larger diameter lower hole The outer diameter of the forming part is formed larger than the piston sliding part of the largest cylinder hole in all the cylinder holes, and the large diameter lower hole forming part and the piston sliding part lower hole forming part are The step formed between the The plurality of cylinder holes and the openings are formed by a casting mold having a single core formed in a plane perpendicular to the axis of the sliding part lower hole forming part, and the one The core has a vehicle body mounting bracket side protruding portion that protrudes toward the vehicle body mounting bracket, and processes the lower hole forming portion after casting so that a small diameter cylinder hole and a large diameter cylinder hole set in advance are formed. It is characterized by forming each.

The caliper body of the vehicle disc brake according to the present invention is formed on the inner side in the disc radial direction of a pair of action portions arranged to face each other with the disc rotor interposed therebetween, a bridge portion straddling the outside of the disc rotor, and one action portion. A body mounting bracket, and a caliper body in which the disk rotor side facing surface of the body mounting bracket is offset from the disk rotor side facing surface of the one working portion in the disk rotor surface direction is integrally formed with a casting mold, and A pilot hole for forming a plurality of cylinder hole pilot holes, wherein a plurality of cylinder hole pilot holes arranged in parallel in the disk circumferential direction of the action part and an opening part surrounded by the action part and the bridge part are formed. A forming portion and an opening forming portion for forming the opening, and the pilot hole forming portion forms a pilot hole of a piston sliding portion on which the piston slides. A piston sliding part lower hole forming part and a large diameter lower hole forming part that forms a lower hole of a large diameter hole part formed larger in diameter than the piston sliding part on the cylinder hole bottom side. And forming at the time of casting with a core having a vehicle body mounting bracket side protruding portion that protrudes toward the vehicle body mounting bracket, forming a plurality of cylinder holes having different inner diameters by machining the pilot holes after casting, In a caliper body of a monocoque piston-opposed vehicle disc brake that accommodates pistons having different outer diameters in a plurality of cylinder holes, each of the cylinder holes includes a piston sliding portion on which the piston slides, and the piston slide. A large-diameter hole on the bottom side of the cylinder hole larger than the moving part, and the piston sliding part is the piston sliding part of the smallest cylinder hole in all the cylinder holes A plurality of cylinder holes having different inner diameters are formed by machining the pilot holes formed by the piston sliding part pilot hole forming part having a smaller diameter, and each large-diameter hole part is the most in all cylinder holes. Each of the stepped portions formed between the piston sliding portion and the large diameter hole portion is formed in the large diameter lower hole forming portion having a diameter larger than the piston sliding portion of the large diameter cylinder hole, It is characterized by being formed in a plane perpendicular to the axis of the cylinder hole.

  According to the caliper body manufacturing method and caliper body for a vehicle disc brake of the present invention, when casting a caliper body for left side mounting and a right side mounting each having a plurality of cylinder holes having different inner diameters, A pilot hole for the cylinder hole can be formed using the core, and the manufacturing cost can be reduced.

  Further, by forming a step portion formed between the piston sliding portion of the cylinder hole and the large-diameter hole portion on the bottom side of the cylinder hole in a plane shape perpendicular to the axis of the cylinder hole, the inner diameter of the cylinder hole is reduced. Even if they are different, the bearing area length of the piston (effective length of the cylinder hole) can be made the same.

It is II sectional drawing of FIG. It is II-II sectional drawing of FIG. It is III-III sectional drawing of FIG. It is a front view of a disc brake showing an example of the present invention. It is a top view of a disk brake similarly. It is a front view of a core similarly. It is a top view of a core similarly. It is VIII-VIII sectional drawing of FIG. It is IX-IX sectional drawing of FIG. It is a top view of a caliper body similarly. It is XI-XI sectional drawing of FIG. It is a principal part expanded sectional view of a caliper body similarly. It is XIII-XIII sectional drawing of FIG. It is a principal part expanded sectional view of a disk brake similarly. It is a perspective view of a retainer.

  The disc brake 1 shown in the present embodiment is a four-pot piston-opposing disc brake 1 mounted on the left side of the vehicle, and is disposed opposite to both sides across a disc rotor 2 that rotates in the direction of arrow A together with the wheels when the vehicle moves forward. The caliper body 3 having a monocoque structure is integrally formed by casting together with a pair of bridge portions 3c and 3c that connect both side portions in the disk circumferential direction of the pair of action portions 3a and 3b. The caliper body 3 has an opening 3d surrounded by the action portions 3a and 3b and the bridge portions 3c and 3c on the outer peripheral side of the disk.

  A large-diameter cylinder hole 5 that accommodates the large-diameter piston 4 is disposed on the disk delivery side of each operating portion 3a, 3b, and a small-diameter cylinder hole 7 that accommodates the small-diameter piston 6 is disposed on the disk rotor 2 side. They are arranged side by side in the circumferential direction of the disk so as to be opened and opposed two by two. The cylinder holes 5 and 7 have large diameter and small diameter piston sliding portions 5a and 7a on which the pistons 4 and 6 slide on the opening side, and have a larger diameter on the bottom side than the large diameter piston sliding portion 5a. Large-diameter holes 5b, 7b having the same inner diameter are formed continuously, and step portions 5c, 7c formed between the piston sliding portions 5a, 7a and the large-diameter holes 5b, 7b are cylinders. It is formed in a planar shape perpendicular to the axis of the holes 5 and 7. In the piston sliding portions 5a and 7a, the pistons 4 and 6 are slidably accommodated via piston seals 8 and dust boots 9 corresponding to the respective diameters. Between the bottom part including the diameter holes 5b and 7b and the bottom surfaces of the pistons 4 and 6, hydraulic pressure chambers 10 and 11 to which hydraulic fluid is supplied are respectively defined. Further, between the adjacent large-diameter holes 5b and 7b, there are provided liquid through holes 12 and 12 for communicating the hydraulic chambers 10 and 11 with each other.

  Furthermore, ports 3e and 3e are formed in the two hydraulic pressure chambers 10 and 10 facing the disk delivery side from the disk delivery side surfaces of the action portions 3a and 3a, and both ports 3e and 3e are connected to the disk rotor 2. The action portions 3a and 3a are connected by a liquid passage tube 13 disposed along the disk discharge side surface. In addition, the two hydraulic chambers 11 and 11 facing the disk entry side are provided with bleeder holes 3f and 3f from the disk entry side of the action portions 3a and 3a, and each of the bleeder holes 3f has a brewer screw. 14 are respectively screwed. Further, a union boss portion 3g protrudes from the central portion on the side opposite to the disk rotor of the one action portion 3a, and the hydraulic pressure chamber is supplied to the union boss portion 3g through the liquid passage hole 12 through the fluid passage hole 12. A union hole 3h for introduction into 10 and 11 is formed.

  A vehicle body mounting bracket 3i is formed on the inner side in the disk radial direction of one working portion 3a, and mounting bolt insertion holes 3j, 3j are provided on both sides of the vehicle body mounting bracket 3i in the disk circumferential direction. The caliper body 3 is attached to the vehicle body by screwing attachment bolts inserted through the holes 3j and 3j to the vehicle body side.

  At the center of the bridge portions 3c, 3c, rectangular ceiling openings 3k are formed in such a size that the friction pads 15, 15 can be inserted into both sides of the disc rotor 2. The pad mounting recesses 3m and 3m are respectively provided in succession on the disk insertion side surface 3n and the disk extraction side surface 3o of the ceiling opening 3k. The disk insertion side and the disk extraction side of the pad mounting recesses 3m and 3m serve as torque receiving surfaces 3p and 3p that receive torque from the friction pads 15 and 15 during braking, respectively, and these torque receiving surfaces 3p and 3p are intermediate in the disk radial direction. Each part is formed with a retainer mounting recess 3q having a V-shaped cross section. Further, on the inner surface 3r in the disk radial direction of each retainer mounting recess 3q, a retainer 16 disposed on the disk feed-in side and a female screw hole 3s for mounting the retainer 16 disposed on the disk feed-out side are formed. . Further, pad receiving surfaces 3t and 3t for supporting the inner surface 15a in the disk radial direction of the friction pads 15 and 15 are provided on both sides in the disk radial direction of the pad mounting recesses 3m and 3m, respectively. In addition, a rigid member 17 for increasing the rigidity of the bridge portions 3c, 3c is attached to the ceiling opening 3k by mounting bolts 17a, 17a.

  In the caliper body 3 having such a configuration, a part that requires dimensional accuracy, for example, a cylinder including piston seal grooves 5d and 7d in which the piston seal 8 is fitted and dust boot grooves 5e and 7e in which the dust boot 9 is fitted. The holes 5, 7, the torque receiving surfaces 3p, 3p, the retainer mounting recess 3q, the pad receiving surface 3t, and the cylinder hole opening side wall surface 3u of the opening 3d are each processed surfaces that have been finished. As the processing surface, a processing blade corresponding to the processing direction, shape, or the like is selectively used.

  In the finished portion, the torque receiving surface 3p and the pad receiving surface 3t are provided at the corner C1 where the torque receiving surface 3p and the cylinder hole opening side wall surface 3u of the opening perpendicular to the torque receiving surface 3p intersect. A relief recess 3v of a processing blade for cutting is provided. Similarly, the corner C2 where the torque receiving surface 3p intersects with the pad receiving surface 3t orthogonal to the torque receiving surface 3p is also provided with a relief recess 3w of the machining blade for cutting the torque receiving surface 3p and the pad receiving surface 3t. Is provided. The opening width with respect to each surface in these relief recesses 3v and 3w is set to a dimension that is not less than the radius of the machining blade for finishing each surface and does not impair the function of each surface, for example, the function as a torque receiver on the torque receiving surface 3p. Has been. Further, the relief recess 3v provided at the corner between the torque receiving surface 3p and the cylinder hole opening side wall surface 3u is provided from the inner side to the inner end in the disc radial direction from the outer side in the disc radial direction of the corner C1. A portion A1 where no escape recess 3v exists is provided at the outer end portion of the corner portion C1 in the disk radial direction.

  The friction pad 15 is composed of a lining 15b and a metal back plate 15c. With each lining 15b facing the disk rotor 2, the side of the disk rotor 2 and the side surfaces of the disk rotor 2 are received from the ceiling opening 3k. It is inserted between the surfaces 3p, 3p and the cylinder hole opening side wall surface 3u, and is disposed on the front surface of the cylinder holes 5, 7.

  The retainer 16 guides the friction pad 15 at the time of braking in the disk axial direction, and is arranged on each of the disk feed-in side and the disk feed-out side. Each retainer 16 connects a pair of torque receiving pieces 16a and 16a laid on adjacent torque receiving surfaces 3p and 3p across the disk rotor 2 to the disk outer peripheral side of the torque receiving pieces 16a and 16a, respectively. And a connecting portion 16b disposed across the disc rotor 2 along the disc feeding side surface 3n or the disc feeding side surface 3o of the ceiling opening 3k. Further, a mounting portion 16c that is bent corresponding to the V shape of the retainer mounting recess 3q is formed at the intermediate portion in the disk radial direction of each torque receiving piece 16a, and the inner surface in the disk radial direction of the mounting portion 16c. 16d is formed with a bolt hole 16e through which a retainer mounting bolt 18 for mounting the retainer 16 to the caliper body 3 is inserted. Further, the inner end of the torque receiving piece 16a in the disk radial direction is bent along the pad receiving surfaces 3t and 3t, and pad receiving pieces 16f and 16f for supporting the back plate 15c of the friction pad 15 are formed respectively. Yes. Further, the retainer 16 on the disk entry side is provided with a curved portion 16g projecting toward the disk delivery side at the center in the radial direction of the disk of the torque receiving piece 16a, and the friction pads 15 and 15 are moved around the disk by the curved portion 16g. It pushes against the exit side.

  The retainer mounting recess 3q into which the mounting portion 16c of the retainer 16 is inserted has a concave shape slightly larger than the protruding shape of the mounting portion 16c, and the inner surface in the disk radial direction of the mounting portion 16c in which the bolt hole 16e is formed. The finishing process described above is applied to the inner surface 3r in the disk radial direction of the retainer mounting recess 3q with which 16d abuts. In addition, the corner where the inner surface 3r in the disk radial direction of the retainer mounting recess 3q intersects the torque receiving surface 3p on the inner side in the disk radial direction, the outer surface 3l in the disk radial direction, and the torque receiving surface 3p on the outer side in the disk radial direction. Chamfered portions 3x, 3x are respectively provided at the corners where the disk intersects, and the inner surface of the corner where the disk radial inner side surface 16d of the mounting portion 16c and the torque receiving piece 16a inside the disk radial direction intersect, Between the outer surface of the chamfered portion 3x, an inner surface of a corner portion where the disk radial direction outer surface 16h of the mounting portion 16c and the torque receiving piece 16a on the outer side of the disk radial direction intersect, and an outer surface of the chamfered portion 3x A gap E1 is provided between each of them.

  When manufacturing such a caliper body 3 by casting, a casting mold is used in which a plurality of outer molds that form the outside of the caliper body 3 and a core that forms the inside are combined. The core 20 includes four lower hole forming portions 21 that respectively form the lower holes of the four cylinder holes 5 and 7, an opening forming portion 22 that forms the opening 3d, and the adjacent lower hole forming portions 21. A liquid passage hole forming portion 23 connecting the bottom side and a vehicle body mounting bracket side protruding portion 24 are provided. Each of the lower hole forming portions 21 includes a piston sliding portion lower hole forming portion 21a that forms a lower hole of the piston sliding portions 5a and 7a on which the pistons 4 and 6 slide, and a large diameter hole portion 5b on the cylinder hole bottom side. , 7b is continuously provided, and the outer diameter of the piston sliding portion lower hole forming portion 21a is smaller than the inner diameter of the piston sliding portion 7a of the small diameter cylinder hole 7. In addition, the outer diameter of the large diameter lower hole forming portion 21b is formed larger than the inner diameter of the piston sliding portion 5a of the large diameter cylinder hole 5, and the caliper body center of the large diameter lower hole forming portion 21b is formed. The side surface 21c is formed in a planar shape orthogonal to the axis of the piston sliding portion lower hole forming portion 21a. The opening forming portion 22 includes a cylinder hole opening side wall surface forming portion 22a, a pad mounting recess forming portion 22b, a torque receiving surface forming portion 22c, and a retainer mounting recess forming portion 22d, and the torque receiving surface forming portion 22c and The relief recesses 3v and 3w are formed at the corner where the cylinder hole opening sidewall surface forming portion 22a intersects and at the corner where the torque receiving surface forming portion 22c and cylinder hole opening sidewall surface forming portion 22a intersect. Protrusions 22e and 22f are provided respectively. Further, chamfer forming portions 22g and 22g are provided at portions where the chamfered portions 3x and 3x of the retainer mounting recess 3q are formed.

  The original caliper body cast using such a core 20 has four piston sliding portions having the same diameter (D2) smaller than the inner diameter (D1) of the piston sliding portion 7a of the small diameter cylinder hole 7. A hole, a large-diameter lower hole having a larger diameter (D4) than the inner diameter (D3) of the piston sliding portion 5a of the large-diameter cylinder hole 5, and an opening forming portion slightly smaller than the size of the opening 3d are formed. Has been. The caliper body prototype is subjected to a predetermined heat treatment in a heat treatment furnace, and then the piston sliding portion lower hole has a predetermined machining blade according to the diameter of the piston sliding portions 5a and 7a of the cylinder holes 5 and 7, respectively. In addition, the piston seal grooves 5d and 7d for fitting the piston seal 8 and the dust boot grooves 5e and 7e for fitting the dust boot 9 are finished by a predetermined machining blade, respectively. The opening forming portion is subjected to predetermined finishing on the rotor groove 3y, the torque receiving surface 3p, the inner surface 3r in the disk radial direction of the retainer mounting recess 3q, and the like. Further, the ports 3e and 3e, the bleeder holes 3f and 3f, and the union hole 3h are drilled. During this finishing process, the portions formed by the large-diameter lower hole forming portion 21b and the liquid passage hole forming portion 23 become the large-diameter hole portions 5b and 7b and the liquid passage hole 12 as cast surfaces, and these portions. It is not necessary to perform the finishing process, and the machining work can be simplified.

  Further, in the retainer mounting recess 3q, only the inner surface 3r in the disk radial direction to which the retainer 16 is mounted by the retainer mounting bolt 18 is finished. In this way, in the retainer mounting recess 3q, by finishing the disk radial inner side surface 3r facing the ceiling opening 3k side and mounting the retainer 16, the caliper body 3 having a monocoque structure can be used. Since the retainer 16 can be disposed at a predetermined position and the retainer mounting bolt 18 can be screwed from the ceiling opening 3k, the retainer 16 can be easily and reliably mounted. Moreover, since the retainer 16 is formed by a pair of torque receiving pieces 16a and 16a and a connecting portion 16b, the retainer 16 can be manufactured simply by punching a thin metal plate and bending the mounting portion 16c, the pad receiving piece 16f, or the like. Compared to conventional retainers, the shape is simple, and productivity can be improved and production costs can be reduced. Further, the retainer 16 on the disk entry side is provided with a curved portion 16g that protrudes toward the disk delivery side so that the friction pad 15 is pressed against the disk delivery side, so that rattling of the friction pad 15 is suppressed. Can do. Further, when the retainer 16 is attached, the chamfered portion 3x chamfers the portion where the bent portion between the inner surface 16d in the disk radial direction of the mounting portion 16 and the torque receiving piece 16a on the inner side in the disk radial direction is located. Therefore, even if there is a manufacturing error in the retainer mounting recess 3q or the retainer 16, it is possible to avoid interference between the corner portions of the retainer 16, improve the seating of the torque receiving piece 16a of the retainer 16, and improve the torque receiving piece. The inner portion of the disk 16a in the radial direction of the disk 16a can be reliably arranged on the torque receiving surface 3p, and the friction pad 15 can be guided well. In addition, the chamfered portion 3x can be easily formed by forming the chamfered portion 3x with the core 20 during casting.

  Further, the original torque receiving surface 3p of the caliper body by the convex portions 22e and 22f provided at the corners of the torque receiving surface forming portion 22c of the core 20, and the cylinder hole opening side wall surface of the opening perpendicular to the torque receiving surface 3p. Since the relief recesses 3v and 3w are respectively formed in the corner portion between 3u and the corner portion between the torque receiving surface 3p and the pad receiving surface 3t orthogonal thereto, the torque receiving surface 3p and the cylinder hole Since the processing blade 30 for finishing the opening side wall surface 3u and the pad mounting recess 3m can be processed without contacting the surfaces adjacent to both ends of the finishing surface, the processing blade 30 can be used in a good state. In addition, each of these surfaces, particularly the torque receiving surface 3p that requires high precision, can be finished reliably and satisfactorily.

  That is, as shown in FIG. 13, conventionally, after finishing each surface with, for example, the machining blade 30, the corner C <b> 1 (C <b> 2) is finished with the machining blade 31 having a smaller diameter than the machining blade 30. In contrast, by providing the relief recesses 3v (3w), the corners C1 (C2) can be satisfactorily finished with only the processing blade 30 for finishing each surface. It is possible to reduce time, the type of machining blade, and the like. The opening widths of the relief recesses 3v and 3w may be equal to or slightly larger than the radius of the machining blade for machining the orthogonal surfaces.

  Further, the dimension of the portion A1 where the relief recess 3v does not exist at the outer end portion in the disk radial direction of the corner portion C1 is set in a range that does not affect the mounting and operation of the retainer 16 and the friction pad 15, thereby preventing finishing. Even if it is sufficient, there is no problem, and by providing such a thick portion having an arc with a large radius, the strength of the portion where the torque receiving surface 3p intersects with the cylinder hole opening side wall surface 3u is improved and the rigidity of the caliper body 3 is increased. Can be held. Moreover, the relief recesses 3v and 3w can be easily formed by forming the relief recesses 3v and 3w with the core 20 during casting.

  Further, in the case of a caliper body in which a plurality of cylinder holes having different inner diameters in the circumferential direction of the disc are arranged side by side, the caliper body of the disc brake mounted on the right side of the vehicle and the caliper body on the left side of the vehicle shown in the above embodiment are The mounting direction of the mirror is mirror-symmetrical, and a core with a large-diameter large-bore cylinder hole pilot hole forming portion and a small-diameter small-diameter cylinder hole pilot hole forming portion is provided according to the cylinder hole diameter. In this case, it is necessary to prepare two types of cores for the right side and the left side due to the relationship between the body mounting bracket and each of the large and small diameter cylinder holes. The piston sliding part lower hole forming part 21a of the hole 5, 7 that forms the piston sliding part 5a, 7a is formed to have a smaller diameter than the piston sliding part 7a of the small diameter cylinder hole 7 and is located at the bottom of the cylinder hole. The lower diameter hole forming portion 21b is formed to have a larger diameter than the piston sliding portion 5a of the large diameter cylinder hole 5, and the large diameter lower hole forming portion 21b and the piston serving as the caliper body central side surface 21c of the large diameter lower hole forming portion 21b. A step portion formed between the sliding portion lower hole forming portion 21a is formed in a planar shape perpendicular to the axis of the piston sliding portion lower hole forming portion 21a, and is large corresponding to the right side and the left side after casting. By machining the diameter and small diameter cylinder holes 5 and 7, both the right side and the left side can be used by changing the direction of the core 20 during casting according to the direction of the vehicle body mounting bracket side protrusion 24. It becomes possible to do. Therefore, the number of cores can be reduced to one, the number of molds for manufacturing the core can be reduced to one, and the caliper body can be mixed with each other when casting the caliper body. Can improve workability and reduce manufacturing costs.

  Further, the caliper body central side surface 21c of the large diameter lower hole forming portion 21b is made flat, so that the lower hole formed by the piston sliding portion lower hole forming portion 21a corresponds to the piston sliding portion 7a of the small diameter cylinder hole 7. Since it is possible to make the piston bearing area length (effective length of the cylinder hole) the same when processing to a small diameter and when processing to a large diameter corresponding to the piston sliding portion 5a of the large diameter cylinder hole 5. The piston stroke in both cylinder holes can be made the same, and the piston can be operated satisfactorily.

  The present invention is not limited to the above-described embodiment. For example, the present invention can be applied not only to a 4-pot opposed caliper body but also to a 6-pot or larger opposed caliper body, and a cylinder hole. The diameter of is also arbitrary.

  DESCRIPTION OF SYMBOLS 1 ... Disc brake, 2 ... Disc rotor, 3 ... Caliper body, 3a, 3b ... Action part, 3c ... Bridge part, 3d ... Opening part, 3e ... Port, 3f ... Breeder hole, 3g ... Union boss part, 3h ... Union Hole, 3i ... body mounting bracket, 3j ... mounting bolt insertion hole, 3k ... ceiling opening, 3m ... pad mounting recess, 3n ... disk feeding side, 3o ... disk feeding side, 3p ... torque receiving surface, 3q ... retainer Mounting recess, 3r ... inner surface in the radial direction of the disk, 3s ... female screw hole, 3t ... pad receiving surface, 3u ... cylinder hole opening side wall surface, 3v, 3w ... relief recess, 3x ... chamfering portion, 3y ... rotor groove, 4 ... Large diameter piston, 5 ... large diameter cylinder hole, 5a ... piston sliding part, 5b ... large diameter hole part, 5c ... step part, 5d ... piston seal groove, 5e ... dust boot groove, 6 ... small diameter piston 7 ... Small diameter cylinder hole, 7a ... Piston sliding part, 7b ... Large diameter hole part, 7c ... Step part, 7d ... Piston seal groove, 7e ... Dust boot groove, 8 ... Piston seal, 9 ... Dust boot, 10, 11 DESCRIPTION OF SYMBOLS ... Fluid pressure chamber, 12 ... Fluid passage hole, 13 ... Fluid passage tube, 14 ... Breuder screw, 15 ... Friction pad, 15a ... Radial inner surface of disk, 15b ... Lining, 15c ... Back plate, 16 ... Retainer, 16a ... Torque receiving piece, 16b ... Connecting part, 16c ... Mounting part, 16d ... Disc radial inner surface, 16e ... Bolt hole, 16f ... Pad receiving piece, 16g ... Bending part, 17 ... Rigid member, 17a ... Mounting bolt, 18 Retainer mounting bolt, 20 ... Core, 21 ... Lower hole forming portion, 21a ... Piston sliding portion lower hole forming portion, 21b ... Large diameter lower hole forming portion, 21c ... Caliper body central side surface, 22 ... Open Part forming part, 22a ... Cylinder hole opening side wall surface forming part, 22b ... Pad mounting recessed part forming part, 22c ... Torque receiving surface forming part, 22d ... Retainer mounting recessed part forming part, 22e, 22f ... Projecting part, 22g ... Chamfer forming , 23 ... Liquid passage hole forming part, 24 ... Car body mounting bracket side protruding part, 30, 31 ... Processing blade, C1, C2 ... Corner part, E1 ... Gap

Claims (2)

A pair of action portions arranged opposite to each other with the disc rotor interposed therebetween, a bridge portion straddling the outside of the disc rotor, and a vehicle body mounting bracket formed on the inner peripheral side of the one operation portion in the disk radial direction, A caliper body whose disk rotor side facing surface is offset from the disk rotor side facing surface of the one working part in the disk rotor surface direction is integrally formed by a casting mold, and the inner diameter of the working part arranged in parallel in the disk circumferential direction Monocoque piston facing each other, wherein a plurality of cylinder holes having different diameters and an opening surrounded by the action portion and the bridge portion are formed by a core during casting, and pistons having different outer diameters are respectively accommodated in the plurality of cylinder holes. In a caliper body manufacturing method for a type of vehicle disc brake,
A lower hole forming portion for forming the plurality of cylinder holes and an opening forming portion for forming the opening, wherein the lower hole forming portion is below a piston sliding portion on which the piston slides. The piston sliding part lower hole forming part that forms the hole and the large diameter pilot hole forming part that forms the lower hole of the large diameter hole part formed to have a larger diameter than the piston sliding part on the cylinder hole bottom side are continuous. The outer diameter of the piston sliding part lower hole forming part is smaller than the piston sliding part of the smallest cylinder hole in all the cylinder holes, and the outer diameter of the large diameter lower hole forming part is all And a step portion formed between the large diameter lower hole forming portion and the piston sliding portion lower hole forming portion. Is a plane perpendicular to the axis of the piston sliding part pilot hole forming part A casting mold having a single core formed on the vehicle body, wherein the plurality of cylinder holes and the openings are formed, and the single core projects toward the vehicle body mounting bracket. Has a mounting bracket side protrusion,
A method for producing a caliper body for a disc brake for a vehicle, wherein the lower hole forming portion after casting is processed to form a preset small diameter cylinder hole and a large diameter cylinder hole, respectively. A pair of action portions arranged opposite to each other with the disc rotor interposed therebetween, a bridge portion straddling the outside of the disc rotor, and a vehicle body mounting bracket formed on the inner peripheral side of the one operation portion in the disk radial direction, a plurality arranged in parallel with integrally formed, in the disk circumferential direction of the working portion of the caliper body which is offset in the disc rotor face direction from the disc rotor side opposing face the disc rotor side facing surface of said one of the working portion at the casting mold An opening for forming the plurality of cylinder holes, and an opening for forming the opening. A piston sliding part lower hole forming part which forms a pilot hole of the piston sliding part on which the piston slides, and a cylinder hole bottom side side. A vehicle body mounting bracket side that continuously includes a large diameter pilot hole forming portion that forms a pilot hole of a large diameter hole portion that has a larger diameter than the piston sliding portion, and protrudes toward the vehicle body mounting bracket side A monocoque that is formed at the time of casting with a core having a projecting portion, the pilot holes are machined after casting to form a plurality of cylinder holes with different inner diameters, and pistons with different outer diameters are accommodated in the cylinder holes, respectively. In the caliper body of the disc brake for vehicles with the structure piston facing type,
Each cylinder hole is continuously provided with a piston sliding part on which the piston slides and a large diameter hole part on the cylinder hole bottom side larger in diameter than the piston sliding part,
The piston sliding part has a plurality of different inner diameters by machining the pilot hole formed by the piston sliding part lower hole forming part having a smaller diameter than the piston sliding part of the smallest cylinder hole in all the cylinder holes. Formed in each cylinder hole,
Each of the large-diameter hole portions is formed in the large-diameter lower hole forming portion having a larger diameter than the piston sliding portion of the largest-diameter cylinder hole in all the cylinder holes,
A caliper body for a disk brake for a vehicle, wherein a step portion formed between the piston sliding portion and the large-diameter hole portion is formed in a planar shape perpendicular to the axis of the cylinder hole.

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