Elastic cup fixture for cup inner diameter sliding type master cylinder

Abstract

The present invention relates to an elastic cup jig that can detachably mount an elastic cup in a groove formed on the inner wall of a cup-inner-diameter sliding master cylinder. [Solution] The device comprises a cylindrical main body 10, legs 15 separated from the cylindrical main body 10, a partial cutout 11 provided therebetween, a lifting shaft section 12 which moves up and down along the axis of the cylindrical main body 10, the partial cutout 11 provided between the legs 15 separated from the cylindrical main body 10, a flat guide section 13 which is suspended between the cylindrical main body 10 and the legs 15, and a hook section 14 which moves along the lifting shaft section 12 and extends beyond the cylindrical main body 10 to the legs 15, and the hook section 14 can be extended via the lifting shaft section to attach and detach an elastic cup 20 to the annular groove.

Description

[Technical field]

[0001] The present invention relates to an elastic cup jig that can detachably mount an elastic cup in a groove formed on the inner wall of a cup-inner-diameter sliding master cylinder. [Background technology]

[0002] An example of a cup inner diameter sliding type master cylinder is described in Japanese Patent No. 4498718 as "a master cylinder in which a piston slides on the inner circumference of a cup held in a cylinder body to pressurize brake fluid in a pressure chamber, the piston having a uniform outer diameter over the entire length, the piston, a cup housing groove provided on the inner circumference of the cylinder body, a primary cup housed in the cup housing groove, a plurality of axial grooves for communicating the cup housing groove with the pressure chamber provided on the inner circumference of the cylinder body in front of the primary cup, and a plurality of ply-type master cylinders each having a cup housing groove and a primary cup housing groove provided on the inner circumference of the cylinder body in front of the primary cup, the primary cup housing groove being a plurality of axial grooves for communicating the cup housing groove with the pressure chamber, and the primary cup housing groove being a plurality of ply-type master cylinders each having a cup housing groove and a primary cup housing groove. An example of a master cylinder is shown which comprises an annular wall formed integrally with the cylinder body behind a primary cup and having an inner diameter larger than that of the cylinder body, an annular passage provided between the annular wall and the piston, and a communicating passage provided at the rear of the annular wall with a reservoir having a gap between the piston and the piston larger than that of the annular passage, wherein the annular passage is formed as a passage corresponding to a sudden return of the piston, and when the piston is suddenly returned, brake fluid is sucked from the reservoir into the pressure chamber through the annular passage, around the primary cup, and further through the axial groove. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent No. 4498718 Summary of the Invention [Problem to be solved by the invention]

[0004] In this type of cup inner diameter sliding type master cylinder, the elastic cup must be attached to and slid against an annular wall provided on the inner surface of the cylinder body, so the cup must be inserted into the inner surface of the cylinder beforehand when the cylinder is made. Also, when replacing the cup, only the cup must be removed, which requires care not to scratch or damage the inner surface of the cylinder, making this work complicated and time-consuming. However, this invention uses an elastic cup tool to eliminate the aforementioned drawbacks.

[0005] The problem that this invention aims to solve is to provide a cup jig for a cup inner diameter sliding type master cylinder that can easily attach an elastic cup to an annular groove formed on the inner surface of the cylinder without scratching or damaging the inner surface of the cylinder. [Means for solving the problem]

[0006] The device comprises a cylindrical body 10 which can slide up and down along the inner wall of the cylinder, a cutout 11 provided on the lower part of the cylindrical body 10 (right side in the figure), a lifting shaft 12 which moves up and down along the axis of the cylindrical body 10, a flat guide part 13 which extends downward along the inner surface of the cylindrical body 10 beyond the cutout 11, and a leg part 15 which fixes the lower end of the flat guide part 13 and is connected to the bottom of the cylindrical body 10 via the cutout 11, and an elastic cup 20 is set in the cutout 11 by fitting it externally to the hanging part 14 at the tip of the lifting shaft part 12 and exposing it (see Figure 4).

[0007] Thereafter, the lifting shaft portion 12 is pushed out, and the hanging portion 14 is moved in the extension direction of the lifting shaft portion 12 as shown in FIG. 5, and elastic deformation is caused by the hanging portion 14 of the elastic cup 20 that is hooked onto the partial cutout portion 11, thereby applying a repulsive force to the elastic cup 20.

[0008] In this state, when the leg portion 15 which forms the lower end of the cylindrical body 10 is pressed against the inner bottom of the cylinder, it fits into the annular groove recessed into the inner peripheral surface of the cylinder of the elastic cup 20 . The elastic cup 20 is deformed from the cutout 11, and the protruding portion can be automatically inserted into the annular groove by elastic force (see FIG. 7).

[0009] Conversely, when removing the elastic cup 15 fitted in the annular groove G, the partial cutout portion 11 of the sliding shaft portion 12 can be moved from top to bottom into the annular groove G to remove the elastic cup 20 from the annular groove G. Here, the flat guide portion 13 extends flush with the inner wall 10a of the cylindrical main body 10 and extends beyond the cutout portion 11, and is fixed integrally to the bottom surface of the front recess 15a formed in the leg portion 15. Since the lifting length of the lifting shaft portion 12 can be set to a predetermined length, when the lifting shaft portion 12 is raised, the elastic cup 20 can be accurately positioned in the position of the annular groove G. [Brief description of the drawings]

[0010] [Figure 1] FIG. 2 is a side view of the elastic cup fixture of the present invention. [Diagram 2] FIG. 13 is a bottom view of the elastic cup jig. [Diagram 3] FIG. 3 is a cross-sectional view taken along a partially cutaway portion of FIG. 2. [Figure 4] 13 is a side view of the state in which the elastic cup is fitted onto the partially cutout portion. FIG. [Diagram 5] 13 is a side view of a state in which the elastic cup is pulled in one direction via the lifting shaft portion. FIG. [Figure 6] 13 is a side view of the elastic cup jig in a state in which an auxiliary leg portion is added to the leg portion to increase the overall length of the jig. FIG. [Figure 7] 11 is an explanatory diagram of the state in which the elastic cup is attached to and detached from the elastic cup jig in the groove on the inner peripheral wall of the cylinder. FIG. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS EXAMPLES

[0011] With the above-mentioned configuration, the ring portion of the elastic cup 20 has a known, approximately channel-shaped cross section, and the hook portion 14 at the tip of the sliding shaft portion 12 aligns with the open portion of the partial cutout portion 11 and fits into the guide groove 18 formed in the leg portion 15.Therefore, when the sliding shaft portion 12 is pulled up along the cylindrical main body 10 in the direction of the annular groove G, the elastic cup 20 is stored by being compressed, bent and deformed from the flat guide portion 13 and the partial cutout portion 11 to the outside of the cylindrical main body 10 by the opening edge of the partial cutout portion 11 and the flat guide portion 13.

[0012] When the elastic cup 20 moves to a position where it is aligned with the annular groove G formed in the inner peripheral wall of the cylinder C, the elastic cup 20 can be entirely immersed in the annular groove G by the repulsive force of the elastic cup 20.

[0013] Similarly, when the elastic cup 20 is sunk in the annular groove G, a part of the outer circumferential edge of the elastic cup 20 protrudes somewhat toward the inner circumferential surface side from the annular groove G when the cylinder is removed. Therefore, by aligning the cylindrical main body 10 with the annular groove G in the cylinder without attaching the elastic cup 20 to the partial cutout portion 11, the protruding portion of the elastic cup 20 in the annular groove G is hooked to the side and engaged with the cylindrical main body 10, thereby allowing the elastic cup 20 to be hooked to the cylindrical main body 10.

[0014] A pointed end 17 is formed on the edge of the opening of the lip of the partially cut-out portion 11 that forms the upper end of the leg portion 15 toward the rear side, making it easier to hook a part of the elastic cup 20 thereon.

[0015] This cylindrical main body 10 is formed so that when the lower end of the leg 15 abuts against the inner bottom C1 of the cylinder C, the hook groove 12b of the lifting shaft 12 fits over the recess of the cutout 11, as described above. Therefore, by connecting the auxiliary leg 25, the length of the leg 15 can be changed as needed to match the length of the inner bottom C1 of the cylinder being used.

[0016] Therefore, in this embodiment, a number of auxiliary legs 25 (see Figure 6) of different overall heights are prepared, and the legs 15 are provided with a screw hole (15b) for connection at the bottom of their lower ends, and the auxiliary legs 25 are provided with a screw (25b) at their upper ends that screws into the screw hole 15b for connection. By preparing auxiliary legs 25 of a specified length so that the cutout portion can be aligned with the annular groove on the inner surface of the cylinder in accordance with the length of the inner bottom of the cylinder, the cylindrical main body 10 can be moved up and down to the desired position.

[0017] Since this device has the above-mentioned configuration, the lower end of the leg 15 or auxiliary leg 25 of the cylindrical main body 10 can be abutted against the inner fixed portion C1 of the cylinder to position it, and the elastic cup 20 can be attached to or removed from the annular groove of the cylinder C without scratching or damaging the inner surface of the cylinder. This invention is not limited to the above-mentioned embodiment, and various design modifications can be made without departing from the spirit and scope of this invention. [Explanation of symbols]

[0018] 1 Elastic cup jig 10 Cylindrical body 10a Inner wall 11 Partially cut out 12 Lifting shaft 13 Flat guide part 14 Latch part 15 Legs 15b Front recess 17 Point 18 Guide groove 20 Elastic Cup 25 Auxiliary legs ? Cylinder C1 Inner bottom of cylinder G Annular groove

Claims

1. an elastic cup jig 1 that is characterized by having a cylindrical main body 10 that can slide up and down along the inner wall of a cylinder, a partial cutout 11 provided between the cylindrical main body 10 and a leg portion 15 separated from it, a lifting shaft portion 12 that moves up and down along the axis of the cylindrical main body 10, the partial cutout 11 provided between the cylindrical main body 10 and the leg portion 15 separated from it, a flat guide portion 13 that is hung between the cylindrical main body 10 and the leg portion 15, a hanging portion 14 that moves along the lifting shaft portion 12 and extends beyond the cylindrical main body 10 to the leg portion 15, an elastic cup 20 that is hung between the partial cutout 11 and the hanging portion 14, and the hanging portion 14 can be stretched via the lifting shaft portion to elastically deform the elastic cup 20, thereby allowing the elastic cup 20 to be attached and detached to an annular groove formed on the inner surface of the cylinder.

2. The elastic cup jig 1 according to claim 1, characterized in that the lower end position of the leg portion 15 is formed so as to match the position of the partial cutout portion 11 of the elastic cup jig 1 and the hanging portion 14 extended by the lifting shaft portion.

3. 3. The elastic cup jig 1 according to claim 1 or 2, characterized in that a guide groove opening toward the cutout portion 11 is formed in the leg portion 15, so that the hook portion 14 can be displaced in the extension direction.

4. An elastic cup jig 1 as described in any one of claims 1 to 3, characterized in that a threaded hole is formed on the bottom surface of the leg portion 15, and a threaded portion that matches the threaded hole is provided at the upper end, and by connecting to the leg portion 15, the overall length of the elastic cup jig can be changed to the desired length.

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