JPH09217667A - Sealing device of bolt - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent a general user from easily readjusting an adjusting bolt by increasing strength of a cap and making the cap in double structure. SOLUTION: A first protection cap 20 consisting of a thin plate constituting a sealing device of a bolt has a pressure part 33 to pressurize an outer periphery of a columnar part 44 of a pump housing 12 on the side of an opening end. Diameter outward direction clicks 34, 36 are a part to be engaged with a ring recessed groove 51 formed on an inner peripheral wall of a second protection cap 21. The second protection cap 21 is constituted of a bottomed cylindrical thick material. An opening end side of the second protection cap 21 is inserted from the side of a hexagonal head part 29 of the bolt 11 at the time of fitting, an inner peripheral wall makes friction contact with diametrically outward direction clicks 34, 36 and slides them while pressing them in the diametrically inward direction, and when the diametrically outward clicks 34, 36 fit in the recessed groove 51, the second protection cap 21 is stopped. The diametrically outward direction clicks 34, 36 of the first protection cap 20 prevents movement of the second protection cap 21 in the axial direction.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a bolt sealing device.

[0002]

2. Description of the Related Art In Japanese Utility Model Publication No. 56-42501 of the prior art, in a bolt sealing device fixed to a mounting portion by a tightening nut, a nut and a sealing cap formed so as to surround the bolt are provided. Is disclosed. This sealing cap has an engagement support portion that engages with the bolt head and a pressing portion that frictionally engages with the peripheral surface of the nut. The engagement support portion is hooked on the head portion of the bolt, and the sealing cap is fixed to the nut by the pressing portion.

[0003]

However, according to the bolt sealing device disclosed in Japanese Utility Model Publication No. 56-42051, since the sealing cap is formed of a thin metal plate, the sealing cap is intentionally used with a general tool. If this is to be broken, there is a problem that the sealing cap can be easily removed and the adjustment position of the bolt can be adjusted by the user.

The present invention has been made in order to solve such a problem. By increasing the strength of the cap and making the cap a double structure, general users can easily readjust the adjusting bolt. It is an object of the present invention to provide a bolt sealing device that can be prevented.

[0005]

The present invention for solving the above problems employs the means described in claim 1. According to this means, it is possible to form a sealing structure that cannot be easily broken by forming the protective cap in a double structure. Further, since the second protective cap cannot be easily removed once it is fitted, it is prevented from being readjusted by general users. As a result, the bolt seal can be made solid. Furthermore, if the required strength is low, the second protective cap can be omitted with only the first protective cap.

[0006]

Embodiments of the present invention will be described below with reference to the drawings. (First Embodiment) A bolt sealing device according to a first embodiment of the present invention is shown in FIGS. 1, 2 and 3. The first embodiment is a distribution type fuel injection pump for a diesel engine,
It is an example in which the bolt sealing device of the present invention is applied to a fuel adjusting member that regulates the maximum value of the fuel injection amount.

As shown in FIG. 1, a bolt 11 is screwed into a screw hole 13 of a pump housing 12 which is a mounting member, and the first tightening nut 1 is attached to the outer end side of the bolt 11.
6 and the second tightening nut 18 are tightened, and these nuts 1
First protective cap 20 so as to cover around 6 and 18
And a second protective cap 21 is attached. Hereinafter, the bolt 11, the first tightening nut 16, and the collar 2 shown in FIG.
3, the second tightening nut 18, the first protective cap 20, and the second protective cap 21 will be described in detail.

(1) The bolt 11 has a first screw portion 25 and a second screw portion 25.
It has a screw portion 26, the first screw portion 25 is screwed into the screw hole 13 of the pump housing 12, and the second screw portion 26 is a screw portion for fastening the first tightening nut 16 and the second tightening nut 18. is there. The amount of protrusion of the bolt 11 into the pump housing 12 is determined by adjusting the amount of protrusion of the tip 28 of the bolt 11 that protrudes into the pump housing 12 by the screwing amount of the bolt 11. Bolt 11
A hexagonal head 29 is formed at the outer end of the. The hexagonal head portion 29 is a portion for screwing a bolt.

(2) The first tightening nut 16 is inserted from the hexagonal head 29 side of the bolt 11 and is tightened and fixed to the pump housing 12 via the washer 31. As a result, the pump housing 12 at the tip 28 of the bolt 11 is
The amount of protrusion inside the is determined. (3) The collar 23 is a hollow cylindrical member having a C-shaped cross section. The collar 23 is inserted from the hexagonal head 29 side of the bolt 11, and is loosely inserted from the upper side of the first tightening nut 16 to the outer peripheral portion of the second screw portion 26. The axial length of the collar 23 determines the axial distance between the first tightening nut 16 and the second tightening nut 18.

(4) The second tightening nut 18 is formed from the side of the collar 23 opposite to the first tightening nut 16 to the second screw portion 2 of the bolt 11.
It is screwed to 6 and fixed. This second tightening nut 1
8 has a role of locking a first protective cap 20 described later. (5) The first protective cap 20 is made of a thin plate and has a bottomed cylindrical tubular body as a basic shape. This first protection cap 20
A pressing portion 33 that presses the outer circumference of the cylindrical portion 44 of the pump housing 12 is provided on the open end side. The pressing portion 33 is formed so as to be depressed in the radial inward direction of the cylindrical first protection cap 20. Further, the first protective cap 20 is formed with radially outward claws 34, 35, 36, 37 that can be bent radially outward at equal intervals. These radial outward claws 34, 35, 3
Reference numerals 6 and 37 are portions that are engaged with an annular groove 51 formed in the inner peripheral wall of the second protective cap 20 described later. Further, the first protective cap 20 has the radially outward claws 34, 3
Inner radial claws 38, 39, 40, 41 are provided on the bottom sides of 5, 36, 37 at positions not overlapping in the axial direction. The radially inner claws 38, 39, 40, 41 are portions to be locked by the second tightening nut 18. The second protective cap 20 is attached by being pushed in from the outer end side of the bolt 11, the pressing portion 33 slides while frictionally contacting the outer periphery of the columnar portion 44, and the radially inner claws 38, 39, 40, 41 are moved to the second side. After overcoming the tightening nut 18, push it to the position shown in FIG. Outer radial claws 34, 35, 36, 37 and inner radial claws 38, 3
9, 40, 41 can be easily formed because the first protective cap 20 is formed of a thin plate material.

(6) The second protective cap 21 is made of a thick material having a cylindrical shape with a bottom, and an annular groove 51 is formed in its inner peripheral wall. As shown in FIG. 1, the annular groove 51 is provided with the radially outward claws 34, 35, 3 of the first protection cap 20.
This is a part for fitting 6, 37 together. At the time of fitting, the opening end side of the second protective cap 21 is inserted from the hexagonal head 29 side of the bolt 11, and the inner peripheral wall makes frictional contact while pressing the radially outward claws 34, 35, 36, 37 in the radially inward direction. Sliding, the radial outer claws 34, 35, 36, 37 are recessed into the groove 51 as shown in FIG.
The second protective cap 21 is stopped at that position when it is fitted to. When the second protective cap 21 shown in FIG. 1 is fitted, the radial outward claws 34, 35, 36, 37 of the first protective cap 20 prevent the second protective cap 21 from moving in the axial direction.

Next, the procedure for sealing the bolt will be described with reference to FIG. First, the screw hole 1 of the pump housing 12
3 screw the first screw portion 25 of the bolt 11 to determine the position of the fuel adjusting member inside the pump housing 12, and screw the axial position of the bolt 11 so that the tip 28 of the bolt 11 abuts on that position. adjust. When the screw adjustment amount of the bolt 11 is determined, the washer 31 is inserted from the hexagonal head 29 side of the bolt 11, and then the first tightening nut 16 is screwed and fixed to the second screw portion 26. At this time, the protrusion amount of the bolt 11 inside the pump housing 12 with respect to the pump housing 12 is determined. Next, the hexagonal head 29 of the bolt 11
From the side, insert the collar 23, then the second tightening nut 18
Is fastened and fixed to the second screw portion 26. Next, the first protective cap 20 is inserted from the hexagonal head 29 side, the pressing portion 33 makes frictional contact with the outer peripheral wall of the cylindrical portion 44 of the pump housing 12, and the first protective cap 20 is further pushed. Then, the radially inner pawls 38, 39, 40, 41 are locked by the second tightening nut 18.
1 and falls into the small diameter portion on the side of the collar 23, and as shown in FIG.
39, 40, 41 are locked to prevent the first protective cap 20 from coming off. Next, the second protection cap 21 is pushed in from the outside of the first protection cap 20 so that the radially outward claws 34, 35, 36, 37 slide on the inner peripheral wall of the second protection cap 21 and eventually fit into the annular groove 51. To meet. When fitted, the radially outward claws 34, 35 of the first protection cap 20,
36 and 37 prevent the second protective cap 21 from coming off.
Therefore, the second protective cap 21 cannot be easily removed.

According to the present embodiment, after the bolt 11 is screwed to adjust and fix the protruding amount of the bolt 11, the first tightening nut 16 is tightened, the collar 23 is inserted, and the second bolt is inserted.
The bolt sealing structure can be manufactured by a simple operation of tightening the tightening nut 18, pushing in the first protective cap 20, and further pushing in the second protective cap 21.

According to this embodiment, the first protective cap 20
Since the bolt 11 is covered by the double structure of the second protective cap 21, the bolt 11 cannot be seen from the outside and it is impossible to screw the bolt 11. Further, since the protection cap 21 protects the bolt 11 from the outside, it is not easily damaged. In the above embodiment, the second tightening nut 18 and the collar 23 are separate bodies, but they may be integrated.

[Brief description of drawings]

FIG. 1 is a partial sectional view showing a bolt sealing structure according to a first embodiment of the present invention.

FIG. 2 is a sectional view taken along line II-II shown in FIG.

FIG. 3 is an explanatory view showing the operation of the radially outward pawl when the second protective cap is fitted over the first protective cap.

[Explanation of symbols]

 11 Bolt 12 Pump Housing 13 Screw Hole 16 First Tightening Nut 18 Second Tightening Nut 20 First Protective Cap 21 Second Protective Cap 23 Collar 25 First Screw Part 26 Second Screw Part 31 Washer 33 Pressing Part 34, 35 , 36, 37 radial outward claws 38, 39, 40, 41 radial inward claws 44 columnar portion 51 annular recessed groove

Claims (2)

[Claims] 1. A sealing device which is screwed to a mounting member and seals a bolt fixed to the mounting member by a tightening nut, wherein the mounting member has a screw hole, and the screw member is screwed to the screw hole. A bolt having a first screw part and a second screw part for tightening, a first tightening nut that is tightened on the first screw part, and a loose insertion on the outer periphery of the bolt from above the first tightening nut. A possible collar, a second tightening nut that is tightened to the second screw part from above the collar, a thin plate having a bottomed tubular shape, and a pressing part that is pressed against the mounting member to be mounted, and a radial direction. A first protective cap that has an outward radial claw that is bent inward and an internal radial claw that is formed by bending inward, and that is capable of engaging the radial claw with the second tightening nut. Thick bottomed cylindrical shape that can be fitted with the radial outward claws Grooves are formed in the inner circumferential wall, sealing devices of the bolt, characterized in that a slightly larger second protective cap than the outer diameter of inner diameter of the first protective cap. 2. The bolt sealing device according to claim 1, wherein the radially outward claw and the radially inward claw are formed at positions that do not overlap each other in the circumferential direction.