JP4043979B2 - Caliper body manufacturing method and caliper body for disc brake for pin slide type vehicle - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a caliper body of a pin slide type disc brake for use in various traveling vehicles such as automobiles and motorcycles, and more specifically, a method of manufacturing a caliper body by a gravity casting method and a caliper manufactured by the manufacturing method. Regarding the body.
[0002]
[Prior art]
An action part having a cylinder hole disposed on one side of the disk rotor, a reaction part having a reaction force claw disposed on the other side of the disk rotor, and a reaction with the action part on the outer peripheral side of the disk rotor Generally, a caliper body including a bridge portion connecting the portions is cast by a gravity casting method using cast iron, aluminum, or an aluminum alloy as a base material.
[0003]
In the gravity casting method, when casting a molten metal from a casting mold spout into the cavity, the weight of the molten metal is used to fill the entire cavity with the molten metal. For example, when the caliper body is cast. The casting mold is placed with the cylinder hole bottom wall side cavity facing upward and the reaction force claw molding side cavity facing downward, and the upper part of the cylinder hole bottom wall side cavity is made to correspond to the center position of the cylinder hole bottom wall. A caliper body is manufactured by pouring a melt of a base material from an open spout and filling the entire cavity by gravity (see, for example, Patent Document 1).
[0004]
[Patent Document 1]
JP 2001-124117 A (page 5 FIG. 6)
[0005]
[Problems to be solved by the invention]
However, since the caliper body has a larger wall thickness ratio on the bridge side than the anti-bridge part side across the center of the cylinder hole bottom wall, as described above, it should be made to correspond to the center position of the cylinder hole bottom wall of the casting mold. When the molten metal was poured into the cavity from the open spout, it took time to move the molten metal to the bridge portion where the cavity volume was large. For this reason, there is a difference in the time for the molten metal to rotate between the cavity on the bridge part side and the anti-bridge part side, sinking occurs in the cast caliper body, and the caliper body rigidity may be reduced. In addition, it is preferable that the molten metal is filled into the cavity as quickly as possible. However, if the gate is formed in a circular shape, it is difficult for air in the cavity to escape from the gate during filling of the molten metal, and it takes time to fill the molten metal. .
[0006]
Accordingly, the present invention provides a good pin-slide type disc brake for a vehicle that can quickly and reliably turn molten metal to a portion where the thickness ratio becomes large when the caliper body is cast, thereby preventing the occurrence of sink marks and ensuring rigidity. and its object is to provide a Kyaripabo di manufactured by the caliper body manufacturing method and a manufacturing method thereof.
[0007]
[Means for Solving the Problems]
In order to achieve the above object, a caliper body manufacturing method according to the present invention includes a caliper for a pin slide type vehicle disk brake in which an action part having a bottomed cylinder hole and a reaction part having a reaction force claw are connected by a bridge part. In a method of manufacturing a body by a gravity casting method, a casting comprising a split mold that forms a bridge portion side and a split mold that forms an anti-bridge portion side, with a mold dividing line passing through the center of the bottom of the cylinder hole as a boundary. The mold is arranged with the cylinder hole bottom wall side cavity facing upward and the reaction force claw side cavity facing downward, and a substantially square gate opening at the top of the cylinder hole bottom wall side cavity is placed on the anti-bridge part side. The center position of the bottom wall of the cylinder hole is such that the amount of molten metal that flows into the bridge section with a larger wall thickness ratio flows more than the amount of molten metal that flows into the anti-bridge section. Opened by shifting the Luo bridge direction, by pouring molten metal of the substrate from該湯opening, characterized in that the molded-said caliper body, in particular, the base material of the caliper body, if it is aluminum or aluminum alloy Is preferred.
[0008]
The caliper body of the present invention is a pin slide type vehicle disc brake manufactured by the above manufacturing method and having a bridge portion connecting an action portion having a bottomed cylinder hole and a reaction portion having a reaction force claw. Oite to Kyaripabo di, a substantially square-shaped sprue corresponding positions one formed in the cylinder bore bottom wall by gravity casting, from the center of the cylinder hole bottom wall, is shifted to the large bridge direction of thickness ratio In particular, the caliper body base material is preferably aluminum or an aluminum alloy .
[0009]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, an embodiment of the present invention will be described in detail with reference to the drawings. The disc brake 1 includes a disc rotor 2 that rotates in the direction of arrow A when the vehicle travels, a caliper bracket 3 fixed to the vehicle body on one side of the disc rotor 2, and a pair of slide pins on the caliper bracket 3. The caliper body 5 is slidably supported in the disk rotor axial direction via 4 and 4, and the pair of friction pads 6 and 6 are disposed to face each other with the disk rotor 2 interposed therebetween.
[0010]
A pair of caliper support arms 3a, 3a is provided on the disk rotor retraction side and the disk rotor retraction side of the caliper bracket 3, and the caliper support arms 3a, 3a are parallel to the disk rotor shaft on the outside of the disk rotor 2. The caliper body 5 is disposed so as to sandwich the bridge portion 5c. Each of the caliper support arms 3 a is formed with a pin insertion hole that opens toward the action portion 5 a side of the caliper body 5.
[0011]
The caliper body 5 is made of aluminum, and includes an action part 5 a and a reaction part 5 b that are arranged opposite to both sides of the disk rotor 2, and a bridge part 5 c that connects these parts across the outside of the disk rotor 2. . A cylinder hole 7 is provided in the acting portion 5a so as to open to the disk rotor 2 side, and a piston 8 is inserted into the cylinder hole 7 via a piston seal so as to be fluid-tight and movable. A hydraulic chamber 9 is defined between the bottom wall of the cylinder hole 7 and the piston 8, and a reaction force claw 5d is formed integrally with the reaction portion 5b.
[0012]
Slide pin mounting arms 5e and 5e are provided so as to protrude on the disk rotor turn-in side and the disk rotor turn-out side of the action portion 5a. Slide pin insertion holes 5e, 5e are formed with slide pin insertion holes at the tips thereof, and slide pins 4, 4 slide through the pin insertion holes formed in the caliper support arm 3a. Is screwed.
[0013]
A bleeder boss portion 10 projects from the outer circumferential wall of the cylinder hole 7 in the radial direction of the disk rotor. A bleeder hole is formed in the bleeder boss portion 10 so as to communicate with the hydraulic chamber 9, and a bleeder screw is screwed into the bleeder hole. A rubber bleeder cap 13 is attached to the tip of the bleeder screw. A union hole 14 is provided in the center of the bottom wall of the cylinder hole 7 so as to communicate with the hydraulic pressure chamber 9, and hydraulic fluid pressurized by a separate hydraulic master cylinder (not shown) is supplied to the hydraulic pressure chamber 9 through the union hole 14. To be introduced.
[0014]
The bottom wall of the cylinder hole 7 is formed with a single gate mark 15 (position corresponding to the gate of the present invention) slightly raised from the bottom wall of the cylinder hole 7, which became a gate in casting the caliper body 5. Yes. The gate mark 15 is formed in a substantially square shape having the same shape as the gate, and the center O1 of the gate mark 15 is formed to be shifted from the bottom wall center O2 of the cylinder hole 7 toward the bridge portion 5c. Further, on the gate mark 15 around the union hole 14, there are four protrusions 16 for preventing rotation of the hose banjo connected to the union hole 14.
[0015]
The caliper body 5 described above is manufactured by a gravity casting method using aluminum. The casting mold of the caliper body 5 is composed of a split mold that forms the bridge portion side and a split mold that forms the anti-bridge portion side with a mold split line L1 passing through the bottom center O2 of the cylinder hole 7 shown in FIG. Thus, a caliper body cavity is formed inside the abutment of these split molds. The casting mold is arranged with the bottom wall side cavity of the cylinder hole 7 facing upward and the reaction force claw 5d side cavity facing downward, and the molten aluminum is cavityd from the gate provided on the bottom wall forming side of the cylinder hole 7. It is poured into.
[0016]
Since the gate is formed in a substantially square shape as shown in the gate mark 15, the air in the cavity is easily released during the filling of the molten metal, and the molten metal can be filled quickly. In addition, since the gate is greatly opened to the bridge portion 5c side having a large thickness ratio, the molten metal can be effectively turned into the casting mold, and sinking may occur when the caliper body 5 is cast. Therefore, it is possible to manufacture a good caliper body 5 in which rigidity is ensured. It is preferable to adjust the opening position of the pouring gate so that the ratio of the amount of molten metal poured into the bridge portion side and the amount of molten metal poured into the anti-bridge portion side becomes 4 to 3. Since the caliper body 5 thus cast is parted from the parting line L1, the part can be easily parted and can correspond to a large caliper body.
[0017]
Although the present invention is suitable for application to an aluminum caliper body that is relatively difficult to control the temperature during casting as in the above-described embodiment, the present invention is not limited to an aluminum caliper body. Also applicable to caliper bodies made of aluminum alloy.
[0018]
【The invention's effect】
As described above, according to the present invention, when the caliper body is cast, the molten metal can be quickly and reliably turned to a portion where the thickness ratio of the caliper body is large, and a good caliper body without sink The rigidity of the caliper body can be ensured.
[Brief description of the drawings]
FIG. 1 is a front view of a caliper body showing an embodiment of the present invention. FIG. 2 is a sectional view taken along the line II-II in FIG. 1. FIG. 3 is a plan view of a caliper body showing an embodiment of the invention. ]
DESCRIPTION OF SYMBOLS 1 ... Disc brake, 2 ... Disc rotor, 3 ... Caliper bracket, 4 ... Slide pin, 5 ... Caliper body, 5a ... Action part, 5b ... Reaction part, 5c ... Bridge part, 5d ... Reaction force nail, 5e ... Mounting arm , 6 ... friction pad, 7 ... cylinder hole, 8 ... piston, 9 ... hydraulic chamber, 14 ... union hole, 15 ... gate mark, O1 ... center of gate mark, O2 ... center of bottom wall of cylinder hole, L1 ... type secant

Claims (4)

In a method of manufacturing a caliper body of a pin slide type vehicle disk brake by connecting a working part having a bottomed cylinder hole and a reaction part having a reaction force claw by a bridge part by a gravity casting method , the bottom part of the cylinder hole A casting mold composed of a split mold that forms the bridge portion side and a split mold that forms the anti-bridge portion side with the mold dividing line passing through the center as the boundary, with the cylinder hole bottom wall side cavity facing upward, the reaction force claw The side cavity is arranged downward, and a substantially square-shaped spout that opens at the top of the cylinder hole bottom wall side cavity is a molten metal poured into the bridge portion side having a larger thickness ratio than the anti-bridge portion side. The opening is shifted from the center position of the bottom wall of the cylinder hole toward the bridge so that the amount flows more than the amount of the molten metal that flows into the anti-bridge portion side. Crowded in the caliper body manufacturing method of the pin slide type vehicular disc brake, which comprises molded-the caliper body and. 2. The caliper body manufacturing method of a pin slide type vehicle disc brake according to claim 1, wherein a base material of the caliper body is aluminum or an aluminum alloy. Produced by the caliper body manufacturing method according to claim 1, acting portion and, of the pin slide type vehicular disc brake and a reaction portion having a reaction force claws connected by a bridge portion Kyaripabo Di having a bottomed cylinder bore to fraud and mitigating risk substantially rectangular sprue corresponding positions one formed in the cylinder bore bottom wall by gravity casting, that from the center of the cylinder bore bottom wall, is shifted to the large bridge direction of thickness ratio Kyaripabo di pin slide type vehicular disc brake according to claim. 4. The caliper body for a pin slide type vehicle disc brake according to claim 3, wherein the base material of the caliper body is aluminum or an aluminum alloy .

Images