JPH08145184A - Seal structure - Google Patents

Abstract

PURPOSE: To install a protective member to protect the outer peripheral surfaces of a seal ring easily. CONSTITUTION: A seal ring 10 is installed in a V-shaped outer peripheral groove 19 formed annularly and in series on the outer periphery (shoulder part) of sliding side surfaces 14 and 18 of a boss of an arm 11 and a boss 16 of a basket 15. Also a protective ring 1 is fitted closely onto the outer peripheral surface of the seal ring 10. The protective ring 1 is made of reinforced plastic, spring steel, or rubber material of annular flat ring shape, and a part of it is provided with a notch part. Thus the protective ring 1 can prevent the external peripheral surfaces of the seal ring 10 from being worn and damaged by pressing the outer peripheral surfaces of the seal ring 10 in radial direction, and a pin joint can be replaced without removing it.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a seal ring fitted in an outer peripheral groove formed along the outer periphery of each of opposed sliding end faces of two members connected by a pin, and a protection ring for covering the seal ring from the outside. The present invention relates to an improvement in a seal structure including a ring.

[0002]

2. Description of the Related Art FIGS. 11 to 13 show joints between an arm of a hydraulic shovel and a bucket as an example of a seal structure. The pin bearings P1 and P2 near the connection between the arm 21 and the bucket 25 are covered with earth and sand or pressed against the earth and sand during excavation work. Therefore, for example, the arm 21
The outer peripheral shoulders of the sliding side surface 24 of the boss 22 of the arm 21 and the sliding side surface 28 of the boss 26 of the bucket 25 are inserted into the pin bearing P1 at the connection portion between the boss 22 and the bucket 25 so that earth and sand and mud do not enter inside. Smooth tapered surfaces 23 and 27 are formed in the portion, and a synthetic rubber O-ring-shaped seal ring 30 is applied to a V-groove 29 formed across the sliding side surfaces 24 and 28 by an appropriate tightening force. Give and fit. The sliding part inside the pin bearing P1 is grease-lubricated,
Since grease is also supplied to the sliding surfaces 24 and 28 of the bosses 22 and 26, the sliding portion between the seal ring 30 and the tapered surfaces 23 and 27 is lubricated, and a smooth sealing function is maintained. . However, as described above, the joint between the arm 21 and the bucket 25 may sometimes be strongly pressed against earth and sand during excavation work. In the conventional mounting structure, the seal ring 3 is
Since the outer peripheral portion of 0 protrudes outward, this portion is strongly rubbed by the earth and sand, and the outer peripheral side of the seal ring 30 is worn away, and may eventually break and fall off. If the seal ring 30 is lost, a large amount of earth and sand will enter the inside of the pin bearing P1 through the gap between the sliding sides 24 and 28 of the bosses 22 and 26, and wear and galling of both sliding sides will occur, This can cause play and noise. Also, a new seal ring 3 for repair
To insert 0, the pin P must be removed, the bucket 25 must be removed, and the seal ring 30 must be replaced.
It is a complicated work at the work site. Similar problems occur in other joint parts. In the drawing, reference numeral 31 denotes a bearing (bush), and 32 denotes a dust seal.

[0003]

The present invention was devised in view of the above circumstances, and its main problem is to
It is an object of the present invention to provide a seal structure in which a protective member for protecting the outer peripheral surface of the seal ring can be easily attached.

[0004]

In order to solve the above-mentioned problems, in the invention of claim 1, (a). A protective ring is externally fitted so as to cover the outer peripheral surface of the seal ring, (b). The protective ring forms a notch part that partially divides in the radial direction,
A technical measure is taken such that it is urged in a direction to reduce the diameter when it is fitted. In the invention of claim 2, (b).
In place of the structure of (c), the technical means that the protective ring is composed of a plurality of elastic component pieces, and the end portions of each component piece are adhered to form an annular shape. . Here, a locking groove for locking the seal ring may be provided on the inner surface of each of the protection rings. Further, in the invention of claim 5, a pin seal integrally formed with (d). A seal ring and a protective ring which is set wider than the seal ring and covers the outer peripheral surface is provided. (E). A technical measure is taken such that a notch portion that partially divides in the radial direction is formed, and that when it is attached to the outer peripheral groove, it is biased in a direction that narrows the diameter. Here, it is preferable that the notch is formed obliquely in the width direction or the thickness direction.

[0005]

In the inventions of claims 1 and 4, the protection ring for protecting the outer peripheral surface of the seal ring is formed as a single body or integrally with the seal ring into a ring shape, and a part of the protection ring is divided by the notch. Therefore, without removing the pin joint, the notch can be opened as it is and fitted into the outer side of the seal ring or the V groove. Further, according to the second aspect of the invention, the end portions of the plurality of component pieces can be bonded along the outer circumference of the seal ring to form an annular body that covers the seal ring. Further, when the seal ring and the protection ring are separate bodies, if the locking groove is provided in the protection ring, the positioning with the seal ring can be easily performed.

[0006]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A preferred embodiment in which the seal structure of the present invention is used for a joint of a bucket of a hydraulic shovel will be described below with reference to the drawings. First, as shown in FIG. 8, the structure of the joint of the bucket is the same as the structure shown in FIGS. 11 to 13 except for the seal ring.

The seal ring 10 is provided on the boss 1 of the arm 11.
2 and the sliding side surface 1 that faces the boss 16 of the bucket 15.
V formed in a series on the outer circumference (shoulder) of Nos. 4 and 18
It is attached to the outer peripheral groove 19 having a shape. Reference numerals 13 and 17 denote a pair of tapered surfaces forming the outer peripheral groove 19.

Here, the protection ring 1 is made of a flat ring-shaped plastic (fiber reinforced, super high molecular weight polymer, etc.) or spring steel. The protective ring 1 shown in FIG. 1 is a flat plate having an annular shape and is provided with a notch 2 at one part. The protection ring 1 is set to a length that can press the outer peripheral surface of the seal ring in the radial direction. The notch 2 is cut and formed so as to intersect with the axis, in other words, to be inclined with respect to the width direction of the protection ring 1.

In the protective ring 1 shown in FIG. 2, the notch 2 is formed by cutting it in parallel with the axis. In the protection ring 1 shown in FIG. 3, a recess is provided in the center to form the seal ring 1.
A locking groove portion 3 for locking 0 is formed.

The engaging groove portion 3 engages with the outer peripheral tip of the seal ring 10 to position the protective ring 1 and maintain it at a predetermined position. As shown in FIG. 4, the protection ring 1 is attached by widening the notch 2 to a large diameter, fitting it along the outer periphery of the seal ring 10 fitted in the outer peripheral groove 19, and using an elastic restoring force after the fitting. This is performed by narrowing the diameter and pressing the outer peripheral surface of the seal ring 10.

As the protective ring 1'shown in FIG. 5, a plurality of component pieces 1a made of a flat rubber band having a thickness are prepared, and end portions thereof are adhered so as to be wound along the outer circumference of the seal ring 10 and fixed in series. Form into an annular body. Here, the material of the protective ring 1'can be changed according to various uses such as NBR, urethane rubber, foamed rubber, and the like. This component 1a may be provided with a locking groove 3 'at the center.

The locking groove 3 'of the protection ring 1' shown in FIG.
Has a semicircular cross section, and the locking groove portion 3'shown in FIG. 7 has a V groove cross section. The cross-sectional shape of the locking groove is not limited to the above-mentioned embodiment, and may be any groove shape as long as it can be locked with the outer peripheral surface of the seal ring 10.

In the case of the illustrated example, even if the locking groove portion 3'is provided, it may be recessed within the range of the thickness of the component piece 1a. Therefore, when the protection ring 1'is used, the outer surface is flat. be able to. Further, in the protective ring 1 ', a part on the inner surface side may be adhered to one of the bosses 12 and 16 of the arm or the bucket to make it hard to come off.

Next, FIG. 9 shows a different embodiment using a pin seal member 5 in which a seal ring and a protection ring are integrally formed. That is, in this embodiment, the seal ring 5a is an O-ring made of synthetic rubber such as nitrile rubber.

An outer surface of the seal ring 5a is formed as an uneven flat surface, and a flat plate is bent to form a ring-shaped protective ring 5 having elasticity.
b is integrally fixed. As a material of the protection ring 5b, a material different from the seal ring, such as plastic, spring steel, NBR, urethane rubber, or foamed rubber, can be used. Thus, in the present invention, the seal ring 5
The protective ring 5a and the protective ring 5b may be formed by fixing different materials as described above, or may be integrally formed of the same material.

Next, the notch 6 formed in the pin seal member 5 is bias-cut so as to be oblique in the thickness direction, as shown in FIG. When the pin seal member 5 is opened at the notch 6 and fitted in the outer peripheral groove 19 and set, the pin seal member 5 has elasticity so that it can be sealed with an appropriate tightening force.

The pin seal member 5 can be easily fitted into the outer peripheral groove 19 because the cutout 6 is bias cut. Moreover, since the ring-shaped protective ring 5b having elasticity is provided on the outer peripheral side so as to cover the inner seal ring 5a, the seal ring 5a can be prevented from being directly rubbed or pushed by earth and sand, and damaged. Hard to receive. Furthermore, by forming the notch obliquely, the sealing performance is not impaired.

[0018]

According to the present invention, the protection ring is provided with a notch or a component is bonded to form a ring. Therefore, the protection ring can be protected even at an excavation site without removing the pin joint. Rings can be easily installed and replaced. When the seal ring and the protection ring are separate bodies, the protection ring can be made hard to come off from the seal ring by providing the locking groove portion on the inner peripheral surface of the protection ring.

[Brief description of drawings]

FIG. 1 is a diagram showing an example of a protection ring of the present invention, in which (a) is a partial sectional view and (b) is a perspective view.

2A and 2B are views showing an example of a protection ring having different notches, in which FIG. 2A is a partial sectional view and FIG. 2B is a perspective view.

3A and 3B are views showing an example of a protection ring provided with a locking groove, in which FIG. 3A is a partial sectional view and FIG. 3B is a perspective view.

FIG. 4 is a side cross-sectional view showing a mounting state of a protection ring.

FIGS. 5A and 5B are views showing an example of a protection ring using a flat rubber-like component piece, wherein FIG. 5A is a component piece and FIG.

FIG. 6 is a cross-sectional view showing an example of a locking groove portion of a protection ring.

FIG. 7 is a cross-sectional view showing another example of the locking groove of the protection ring.

FIG. 8 is a cross-sectional view showing a mounting state of the protection ring.

FIG. 9 is a cross-sectional view of a main part showing a mounted state of a pin seal member.

FIG. 10 is a sectional view of a main part showing a cutout portion of the pin seal member.

FIG. 11 is a partial side view showing a joint portion between an arm and a bucket.

FIG. 12 is a view along AA in FIG. 11;

FIG. 13 is a sectional view showing a pin bearing portion.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1, 1 'Protective ring 2 Notch 3, 3' Lock groove 5 Pin seal member 5a Seal ring 5b Protective ring 10 Seal ring 11 Arm 12 Boss 13 Tapered surface 14 Sliding side surface 15 Bucket 16 Boss 17 Tapered surface 18 Sliding side surface 19 Outer groove

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Masaya Ito Inventor Masaya Ito 4-10-1 Yoga, Setagaya-ku, Tokyo Inside New Caterpillar Mitsubishi Corporation (72) Inventor Hidetake Motomura 4-10-1 Yoga, Setagaya-ku, Tokyo New Caterpillar Mitsubishi Co., Ltd. (72) Inventor, Shuichi Hazama, 4-10-1, Yoga, Setagaya-ku, Tokyo Inside New Caterpillar Mitsubishi (72) Inventor, Naoshi Watada, 4-chome, Yoga, Setagaya-ku, Tokyo Inside New Caterpillar Mitsubishi Corporation

Claims (6)

[Claims] 1. A seal ring, which is fitted in an outer peripheral groove formed along the outer circumference of each of the facing sliding end faces of two members connected by a pin and seals between the sliding end faces of the two members. In the seal structure, a protection ring is externally fitted so as to cover the outer peripheral surface of the seal ring, and the protection ring partially forms a notch portion that divides in the radial direction, and in the direction of narrowing the diameter during external fitting. A seal structure characterized by being urged. 2. A seal ring, which is fitted in an outer peripheral groove formed along the outer circumference of each of the opposed sliding end faces of the two members connected by a pin and seals between the sliding end faces of the two members. In the seal structure, a protective ring is externally fitted so as to cover the outer peripheral surface of the seal ring, and the protective ring is composed of a plurality of elastic component pieces,
A seal structure characterized in that the end portions of the respective constituent pieces are adhered to form an annular shape. 3. A lock groove for locking the seal ring is provided on the inner surface of the protection ring.
Seal structure described in. 4. The seal structure according to claim 2, wherein one side of the inner peripheral surface of the protection ring is fixed to the outer peripheral surface of one of the opposing sliding end surfaces. 5. A seal ring, which is fitted into an outer peripheral groove formed along the outer circumference of each of the opposed sliding end faces of the two members connected by a pin and seals between the sliding end faces of the two members. In the seal structure, a pin seal integrally formed with a seal ring and a protection ring that is wider than the seal ring and covers the outer peripheral surface is provided, and the pin seal forms a notch part that partially divides in the radial direction. In addition, the seal structure is characterized in that it is urged in a direction to reduce the diameter when it is attached to the outer peripheral groove. 6. The cutout portion is formed so as to extend obliquely in the width direction or the thickness direction.
Or the seal structure described in 5.