JPH0239751Y2 - - Google Patents

Description

[Detailed Description of the Invention] <Industrial Application Field> The present invention relates to a jig for mounting an O-ring in a ring groove on the outer periphery of a member.

<Prior art> As a fuel pump used for internal combustion engines, etc., the inside of a cylindrical case is divided into a fuel suction side space and a fuel discharge side space by a rotor housing that houses a rotor, and the inside is installed in the case. The pump chamber formed between the rotor and the inner wall of the rotor housing changes in volume by a rotor rotationally driven by a motor, and the fuel sucked from the suction side space is discharged to the discharge port side space. There is something.

Conventionally, the O-ring used in such a fuel pump (for example, interposed between the case and the pump head) is usually manually installed in a ring groove on the outer periphery of the pump head.

Here, an overview of the above fuel pump will be explained based on FIG.
The figure shows the pump chamber, which is sucked into the pump chamber formed between the pump ring 4 and the inner wall of the rotor housing consisting of the pump plate 5, and whose volume changes by the rotor 2, which is connected to the rotating shaft 6a of the motor 6 and rotationally driven. A fuel supply pipe (not shown) is discharged into the inner space of the case 7 on the right side of the middle, from a discharge port 8 provided at the right end in the figure, via a diaphragm type fuel damper 9, and from an outlet port 10 formed on the peripheral wall thereof. It is supplied to the fuel injector via a fuel strainer etc.

Pulsations in the flow rate of fuel discharged by the rotor 2 are absorbed by changes in volume of a space defined by a diaphragm 12 that operates against a spring 11 in the fuel damper 9.

Reference numeral 13 denotes a relief valve that opens when the fuel pressure on the discharge side increases to a predetermined value or more, and returns the fuel in the discharge side space to the suction side space to prevent the discharge fuel pressure from increasing.

In such a fuel pump, the ring groove 14 on the outer periphery of the pump head 3 and the brush holder 1
O-rings 17 and 18 are installed in the ring grooves 16, etc. of No. 5, respectively.
is installed.

These O-rings 17 and 18 are conventionally inserted into the ring grooves 14 and 1 by hand as described above.
As shown in FIG. 3A, the O-rings 17 and 18 are guided to the ring groove forming portion by a truncated conical guide member 19.

<Problems to be solved by the invention> However, in this conventional method of manually installing the O-ring, the O-ring is twisted during installation, and if it is installed in the ring groove as it is, the O-ring will become distorted. There was a drawback that the airtightness function of the ring could not be fully demonstrated.

For this reason, conventionally, after installing the O-ring, the bar 3
2, it was necessary to perform the untwisting work as shown in FIG. 3B, which increased the number of troublesome man-hours and resulted in poor workability.

The present invention was developed in view of these conventional problems, and the purpose is to provide a special jig that allows an O-ring to be mounted in a ring groove of a target member with simple operation and without twisting. .

<Means for Solving the Problems> For this reason, the present invention provides an outer cylindrical member that is fitted into the inner periphery of the outer cylindrical member so as to be freely slidable in the axial direction, and whose distal end is always aligned with the opening surface of the distal end of the outer cylindrical member by means of an elastic member. It consists of an inner cylindrical member that is biased to protrude from the inner cylindrical member, an O-ring support for inserting and supporting an O-ring with its inner diameter expanded on the outer periphery of the tip of the inner cylindrical member, and an O-ring insertion groove on the outer periphery. A member support that has a support part that supports an axial end of the member that has the member, and that is fitted into the inner periphery of the inner cylindrical member to freely slide in the axial direction and is always urged toward the distal end of the O-ring support by an elastic member. an O-ring mounting jig, the inner cylindrical member being provided with a locking portion that is latched to the member support when the member support is slid a predetermined distance into the inner cylindrical member; do.

<Operation> Then, by pushing the member support into the O-ring support using the member, the inner cylinder member is pushed into the outer cylinder member, and the O-ring is separated from the outer periphery of the tip of the inner cylinder member, and at the same time, the outer periphery of the member is Insert the ring into the ring groove.

<Example> Hereinafter, an example of the present invention will be described based on FIG. 1.

In the figure, the O-ring mounting jig according to the present invention is composed of an outer cylinder member 20 and an inner cylinder member 21.
Ring support 22 and O-ring mounting groove 23 on the outer periphery
a member supporter 24 that supports a member 26 having
It consists of

The outer cylindrical member 20 is supported on a support surface in a direction in which the axial direction coincides with the vertical direction, and a support leg 20C is formed at the lower end. Further, the outer cylinder member 20 has a small inner diameter portion 20A on the lower end side.
Each has a large inner diameter portion 20B on the upper end side, and an annular groove portion 20a is formed in the stepped portion between the inner diameter portions 20A, 20B. Inner cylinder member 21
is fitted into the inner periphery of the large inner diameter portion 20B of the outer cylinder member 20 so as to be able to freely slide in the axial direction, and is always biased by a spring 25 as an elastic member so that the tip portion protrudes from the opening surface of the tip end of the outer cylinder member 20. be done.
In this case, the spring 25 is connected to the annular groove 20.
a, and the lower end of the inner cylinder member 21 is set from above. Further, the distal end portion of the inner cylinder member 21 has a shape such that its peripheral surface is a conical surface. The member support 24 is fitted into the inner periphery of the inner cylindrical member 21 so as to be freely slidable in the axial direction, and is always urged toward the distal end of the O-ring support 22 by a spring 27 serving as an elastic member.

The member support 24 has the outer cylindrical member 20 on the lower end side.
It has a small outer diameter portion 24A that is fitted into the small inner diameter portion 20A, and a large outer diameter portion 24B that is fitted into the large inner diameter portion 20B on the upper end side, and both outer diameter portions 24A, 24B are connected to each other via a connecting shaft portion 24C.
A hole 24a is formed in the axial direction of the outer diameter portion 24A of this member support 24 and the connecting shaft portion 24C,
A guide member 28 set on the outer cylinder member 20 side is inserted into this hole 24a.

The spring 27 is interposed between the lower end surface of the member support 24 and the base 28A at the bottom of the guide member 28. Further, on the upper end surface of the member support 24,
Recessed portion 24 for fitting and supporting the end of member 26
b is formed. The inner periphery of the inner cylindrical member 21 has a locking portion that is latched to the lower end surface of the outer diameter portion 24B of the member support 24 when the member support 24 is slid a predetermined distance into the inner cylindrical member 21. A locking protrusion 29 is provided.

Next, a method of using such an O-ring mounting jig will be explained.

First, the O-ring 30 with its inner diameter expanded is inserted and supported on the outer periphery of the protruding end of the inner cylinder member 21 from the front end opening surface of the outer cylinder member 20. Set it on top. Next, member 2
6 is set by fitting and supporting its end into the recess 24b of the upper end surface of the member support 24. When the member 26 is pushed down in this state, the member support 24 is first pushed into the inner cylinder member 21 against the elastic force of the spring 27.

Then, when the member supporter 24 is pushed into the inner cylinder member 21 by a predetermined distance, the lower end surface of the outer diameter portion 24B of the member supporter 24 is locked with the locking protrusion 29 on the inner peripheral part of the inner cylinder member 21. The inner cylinder member 21 as well as the member support 24 are pushed in against the elastic force of the spring 25. Thereby, the tip of the inner cylinder member 21 enters into the outer cylinder member 20 with the O-ring 30 remaining on the front end surface of the outer cylinder member 20. At this stage, the O-ring mounting groove 23 on the outer circumferential surface of the member 26 is at the tip surface of the outer cylinder member 20, and the inner cylinder member 21
The O-ring 30, which has been disengaged by the tip end thereof, moves into the O-ring mounting groove 23 with almost no rolling and is automatically fitted into the O-ring mounting groove 23.

According to the O-ring mounting jig having such a configuration, the O-ring 30 can be attached to the O-ring 30 by the simple operation of setting the member 26 on the upper end surface of the member support 24 and pushing it in.
The O-ring 30 can be automatically installed in the ring installation groove 23, and there is no process of shifting and installing the O-ring 30 as in the conventional method, so the O-ring 30 does not get twisted and maintains the airtight function as an O-ring. I can fully demonstrate my abilities. As a result, there is no need to untwist the O-ring using a rod after it is attached, as is the case in the past, and the troublesome man-hours can be reduced and work efficiency can be improved.

In particular, according to the O-ring mounting jig having such a configuration, the O-ring support 22 has a double structure of the inner cylinder member 21 and the outer cylinder member 20, and the inner cylinder member 21 is first
Since the O-ring 30 is configured to slide within the outer cylindrical member 20 and then the member support 24 can slide within the inner cylindrical member 21, the O-ring 30 hardly rolls into the O-ring mounting groove 23. Go to O
Since it is configured to fit into the ring mounting groove 23,
Twisting of the O-ring 30 can be reliably prevented, and the airtightness maintaining function of the O-ring 30 can be more effectively improved.

Furthermore, the O-ring mounting jig has the advantage of being able to be easily automated and improving the productivity of the product.

<Effects of the Invention> As explained above, according to the O-ring installation jig of the present invention, the member having the O-ring insertion groove on the outer periphery is set on the upper end surface of the jig and pushed in, which is a simple operation. The O-ring can be automatically installed in the O-ring installation groove, and there is no process of shifting and installing the O-ring as in the conventional method.
The O-ring is not twisted and can fully perform its airtight maintenance function as an O-ring. As a result,
There is no need to untwist the O-ring after attaching it, unlike in the past, and the troublesome man-hours can be reduced and work efficiency can be improved.

Furthermore, automation of jig operations can be easily implemented, and product manufacturability can be improved.

In particular, according to the O-ring installation jig of the present invention, O
The ring support has a double structure of an inner cylinder member and an outer cylinder member, so that the inner cylinder member first slides within the outer cylinder member, and then the member support slides within the inner cylinder member. Because of the structure, the O-ring moves into the O-ring mounting groove with almost no rolling.
Since it is configured to fit into the O-ring mounting groove, the O-ring
It can reliably prevent twisting of the O-ring, which is the most important thing when installing an O-ring, and has a great practical effect of more effectively improving the airtightness of the O-ring. be.

[Brief explanation of the drawing]

Fig. 1 is a longitudinal sectional view showing an embodiment of the O-ring mounting jig according to the present invention, Fig. 2 is a sectional view showing the structure of a fuel pump in which a conventional O-ring mounting process is adopted, and Fig. 3 A and B are perspective views showing a conventional O-ring mounting process, respectively. 20...Outer cylinder member, 21...Inner cylinder member, 22...
...O-ring support, 23...O-ring mounting groove, 2
4... Member supporter, 25... Spring, 26...
...Part, 27...Spring.

Claims (1)

[Scope of utility model registration request] It consists of an outer cylindrical member and an inner cylindrical member which is fitted into the inner periphery of the outer cylindrical member so as to be freely slidable in the axial direction and is constantly biased by an elastic member so that its tip end protrudes from the opening surface at the tip end of the outer cylindrical member. O on the outer periphery of the tip of the inner cylinder member
It has an O-ring support that fits and supports the ring with its inner diameter expanded, and a support that supports the axial end of the member having an O-ring insertion groove on the outer periphery, and an axial support on the inner periphery of the inner cylindrical member. a member support which is inserted into the inner cylinder member so as to be freely slidable in the direction and is always urged toward the distal end of the O-ring support by an elastic member; A locking portion is provided that locks the member support when the member is slid a predetermined distance, and the member pushes the member support into the O-ring support, thereby pushing the inner cylinder member into the outer cylinder member and releasing the O-ring. An O-ring mounting jig characterized in that the ring is detached from the outer periphery of the tip end of the inner cylindrical member and simultaneously mounted in the ring groove on the outer periphery of the member.