JP2001020925A - Slipping off preventing mechanism of pin-like member - Google Patents

Abstract

PROBLEM TO BE SOLVED: To facilitate the removal of a pin member in overhauling. SOLUTION: A ring-shaped member 3, when turned from its initial position, is pressed inward by the inner peripheral wall of a recessed section 6, and the inner peripheral section of the ring-shaped member 3 is fitted in the recessed groove 4 of a first member 1. In order to remove the first member 1, the ring- shaped member 3 is turned in the direction opposite to the direction mentioned above. Then, the inner diameter of the ring-shaped member 3 becomes larger than the outer diameter of the first member 1, releasing a slipping off preventing mechanism of a pin-like member.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a mechanism for preventing a pin-shaped member such as a track track pin or a work implement pin for attaching a bucket from coming off in a construction machine.

[0002]

2. Description of the Related Art Tracks used in construction machines such as bulldozers and hydraulic shovels are constructed by attaching a grounding foot plate to an endless annular link chain. The link chain has a structure in which a plurality of links are interconnected by pins. FIG. 3 shows a connection structure of the link. As shown in the figure, the link chain has a pair of left and right links 31 and 32 arranged in a longitudinal direction by a predetermined number, and links 31
The front part and the rear part of 32 are connected by a pin 33 and a bush 34. More specifically, the pin 33 is inserted into the bush 34, and the links 31a, 32a
The bush 34 is pressed into the rear holes 41a, 42a, while the pin 33 is pressed into the front holes 41b, 42b of the links 31b, 32b located at the rear. Since the pin 33 and the bush 34 are rotatable, the front and rear links 31a and 31b are articulated to be bendable. In FIG. 3,
Reference numeral 35 denotes a lubricating oil filling hole, and the lubricating oil lubricates between the pin 33 and the bush 34.

In the above crawler belt, a large force acts on the pin 33 in the thrust direction during use. Therefore, in the link chain as described above, a mechanism for preventing the pin 33 from coming off is provided. This is a structure using a C-shaped retaining ring 36, in which concave grooves are provided at both ends of the pin 33, and the retaining ring 36 is fitted in each concave groove. 33
And the links 31 and 32 are restricted from moving relative to each other. In this case, the front holes 41b, 42 of the links 31, 32
Depressions 43, 43 are formed around the opening of b, and the retaining ring 36 is provided with the depressions 43, 43.
Is located at a position near the back end. This is to prevent the retaining ring 36 itself and its surroundings from being worn or damaged by earth and sand during the operation of the machine.

[0004]

However, the above-mentioned conventional pin-shaped member retaining mechanism has a disadvantage that it takes a great deal of trouble to remove the pin 33 at the time of mechanical overhaul or the like. It is link 3 above
The inner peripheral wall and the periphery of the opening of the concave portions 43, 43 of the first and second 32 are worn or damaged by earth and sand during the operation of the machine. As a result, burrs and burrs are generated on the concave portions 43, 43. This is because these burrs and burrs become obstacles when removing the retaining ring 36. That is, when removing the retaining ring 36, a tool tip such as a plier is inserted into a pair of holding holes provided at both ends of the retaining ring 36, and the diameter of the retaining ring 36 is expanded. Although it is necessary to perform the work of taking out the outside of the recessed portion 43, burrs and burrs generated in the recessed portion 43 as described above may cause troubles in the work of inserting the tool tip and the work of taking out the retaining ring 36. It becomes. Therefore, when removing the pins 33, it is necessary to remove the burrs and burrs in advance.
This requires a lot of work.

It is extremely difficult to manually expand the retaining ring 36 in a limited space such as the inside of the concave portion 43, so that the retaining ring 36 must be extended more than necessary. In addition, there has been a problem that the sheet cannot be reused because it is excessively widened.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned conventional drawbacks, and an object of the present invention is to make it possible to easily remove a pin-shaped member at the time of overhaul and the like, An object of the present invention is to provide a pin-shaped member retaining mechanism capable of minimizing damage to the pin-shaped member.

[0007]

Means and Effects for Solving the Problems Claim 1
The pin-shaped member retaining mechanism of the first embodiment is a pin-shaped first member 1.
A second member 2 having an insertion hole 5 into which the first member 1 can be inserted, and a concave portion 6 formed around the opening of the insertion hole 5, and a concave groove provided around the first member 1 And a ring-shaped member 3 fitted in the first member 1. The first member 1 is inserted into the insertion hole 5 of the second member 2, and in this state, the ring is fitted in the concave groove 4 of the first member 1. A pin-shaped member retaining mechanism for restricting relative movement of the first member 1 toward the non-opening side by bringing an end surface of the member 3 into contact with the periphery of the opening of the insertion hole 5 in the recess 6; The ring-shaped member 3
Is configured to be elastically expandable and contractable by cutting off a part in the circumferential direction, and furthermore, the ring-shaped member 3 is rotatably arranged around the axis O of the insertion hole 5 in a state fitted in the recessed portion 6. At the same time, the outer peripheral portion is engaged with the inner peripheral portion 8 of the concave portion 6, and the inner peripheral portion has an initial position equal to or larger than the diameter of the first member 1, and the inner peripheral portion is the first member. Groove 4 smaller in diameter than 1
It is characterized in that it can be rotationally displaced to a retaining position fitted inside.

According to the pin-shaped member retaining mechanism of the first aspect, when the ring-shaped member is rotated from the initial position, the outer peripheral portion of the ring-shaped member engages with the inner peripheral wall of the concave portion. Then, at the retaining position, the inner peripheral portion of the ring-shaped member 3 is fitted into the concave groove 4 of the first member 1, whereby the retaining can be performed. When removing the first member 1 at the time of overhaul or the like, the ring-shaped member 3 is rotated in a direction opposite to the above. Then, the inner diameter of the ring-shaped member 3 becomes larger in the opposite direction to the above, and when the ring-shaped member 3 is rotated to the initial position, the inner diameter of the ring-shaped member 3 becomes larger than the outer diameter of the first member 1, and the retaining mechanism is prevented. The first member 1 is released.
Can be removed.

In the pin-like member retaining mechanism of the first aspect, the assembling can be performed by a simple operation of rotating the ring-shaped member 3 disposed in the recessed portion 6 at the time of assembling. Therefore, it is possible to improve the assembling workability. Also, in the case of overhaul, etc., the pin
Can be removed, and as a result, the work of removing burrs and burrs generated on the inner peripheral wall of the recess 6 and the periphery of the opening can be greatly simplified, and the work efficiency can be improved. Further, since it is not necessary to take out the ring-shaped member 3 to the outside, damage to the ring-shaped member 3 is reduced by that much.

According to a second aspect of the present invention, there is provided a pin-like member retaining mechanism.
The ring-shaped member 3 is characterized in that it is held in the concave portion 6 by the elastic restoring force in the radially expanding direction at the initial position. According to the pin-shaped member retaining mechanism of the second aspect, since the ring-shaped member 3 is held in the recessed portion 6 by its elastic restoring force,
Workability when attaching and detaching the pin-shaped first member 1 is further improved.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, a specific embodiment of a pin-like member retaining mechanism according to the present invention will be described in detail with reference to the drawings. First, FIG. 1A is a plan view of a retaining mechanism, and FIG. 1B is a cross-sectional view taken along line AA in FIG. 1A. As shown in the figure, this retaining mechanism is constituted by a pin 1 as a first member, a link 2 as a second member, and a ring-shaped member 3. The pin 1 is provided with a concave groove 4 at a position near an end thereof. The link 2 has an insertion hole 5 into which the pin 1 is press-fitted, and a recess 6 around the opening of the insertion hole 5. The recess 6 is formed in a shape like a counterbore around the opening of the insertion hole 5, and a bottom surface 7 extending radially outward around the opening of the insertion hole 5, And an annular inner peripheral wall 8 extending axially outward. The ring-shaped member 3 is formed by stamping a metal plate.
The inner peripheral portion is a substantially annular member having a circular shape, a part of which is cut off in the circumferential direction, so that the diameter can be elastically expanded and reduced.

Next, the shape of the outer peripheral portion of the ring-shaped member 3,
FIG. 1 shows the shape of the inner peripheral wall 8 of the recess 6.
The description will be made with reference to (a). In the figure, O indicates the axis of the insertion hole 5 and the pin 1. With the axis O as the center, the outer peripheral portion of the ring-shaped member 3 and the inner peripheral wall 8 of the concave portion 6 are formed so that the diameter gradually changes. First, the right half of FIG. 1A will be described.
The inner peripheral wall 8 of the concave portion 6 is located farthest from the axis O, and then gradually approaches the axis O in a counterclockwise direction, and becomes the state closest to the axis O on the upper side of FIG. . The left half of the figure has the same shape (axially symmetric) as that described above with the phase shifted by 180 ° with respect to the axis O. Reference numerals 9 and 9 denote grip holes for inserting tool tips such as pliers.

The reason why the shape of the outer peripheral portion of the ring-shaped member 3 and the shape of the inner peripheral wall 8 of the concave portion 6 are formed as described above will be described. That is, when the ring-shaped member 3 is rotated counterclockwise around the axis O from the state (initial position) in the position shown in FIG. 1A (initial position) to the position shown in FIG. The outer peripheral portion of the ring-shaped member 3 is pressed inward in the radial direction by the inner peripheral wall 8 of the concave portion 6 at the retaining position), thereby reducing the diameter of the inner peripheral portion of the ring-shaped member 3. .

The procedure for assembling the above-mentioned pin-shaped member retaining mechanism will be described. First, as shown in FIGS. 1A and 1B, the pin 1 is pressed into the insertion hole 5 of the link 2, and the ring-shaped member 3 is inserted and arranged in the recess 6. The press-fitting of the pin 1 is performed until the concave groove 4 reaches an axial position substantially coincident with the opening of the insertion hole 5. Further, the ring-shaped member 3 is inserted into the recessed portion 6 in a state where the diameter is slightly reduced from the free state, and is held in the recessed portion 6 by the elastic restoring force of the ring-shaped member 3 in the radially increasing direction. .
At this time, the inner diameter of the ring-shaped member 3 is desirably substantially equal to or larger than the outer diameter of the pin 1. Then, from this state (initial position), the tip of a tool such as a plier is inserted into the gripping hole 9 and the ring-shaped member 3 is rotated counterclockwise. Then, the outer periphery of the ring-shaped member 3 is moved inward by the inner peripheral wall of the recess 6,
That is, the ring-shaped member 3 is pressed toward the axis O, and as a result, the inner diameter of the ring-shaped member 3 becomes gradually smaller. And FIG.
2 (a), when the assembly is completed (a retaining position) as shown in FIG. 2 (b), the inner peripheral portion of the ring-shaped member 3 is fitted into the concave groove 4 of the pin 1, whereby the pin 1 Can be prevented from coming out to the side opposite to the opening.

Next, a procedure for removing the pin 1 during overhaul or the like will be described. At this time, the tip of a tool such as a plier is inserted into the holding hole 9 of the ring-shaped member 3, and the ring-shaped member 3 is rotated in the clockwise direction opposite to the above. Then, the inner diameter of the ring-shaped member 3 becomes larger in reverse to the above, and FIGS. 1 (a) and 1 (b)
When the pin 1 is rotated to the initial position shown in FIG. 1, the inner diameter of the ring-shaped member 3 becomes larger than the outer diameter of the pin 1 and the retaining mechanism is released, and the pin 1 is moved to the left in FIG. And can be removed.

In the above-mentioned pin-shaped member retaining mechanism, the ring-shaped member 3 is enlarged in diameter by using a tool such as a plier and the like in the conventional manner at the time of assembling. Rather than performing the operation of inserting and fitting into the concave groove 4 of the pin 1, the assembly can be performed by a simple operation of rotating the ring-shaped member 3 disposed in the concave portion 6. Therefore, it is possible to improve the assembling workability. At this time, since the ring-shaped member 3 is held in the recessed portion 6 by its elastic restoring force, the workability is further improved. Further, when the pin 1 is to be removed during overhaul or the like, the pin 1 can be removed only by rotating the ring-shaped member 3. That is, unlike the related art, it is not necessary to take out the ring-shaped member 3 to the outside of the concave portion 6, and as a result,
The work of removing burrs and burrs generated on the inner peripheral wall of the concave portion 6 and around the opening can be greatly simplified. Also at this time, since the ring-shaped member 3 is held in the recessed portion 6 by its elastic restoring force, the workability is further improved.

In the above-described embodiment, the pin-shaped member retaining mechanism is described as an example in which the pin-shaped member is connected to the link 1 in the crawler belt link chain. The retaining mechanism is not limited to the above embodiment, and can be implemented with various changes. For example, FIG. 4 shows a schematic structure of a working machine of a hydraulic shovel, but the above-mentioned pin-shaped member retaining mechanism can be applied to various pins constituting the working machine. In particular, bucket 1
The bucket pins 12 and 13 for pivotally supporting the pin 1 are particularly preferable because they are frequently attached and detached. In this case, in addition to the effect of facilitating attachment and detachment, the weight of the pin fixing portion can be further reduced as compared with the conventional art. There is also an advantage of achieving the goal. In the above embodiment, the outer peripheral portion of the ring-shaped member 3 and the inner peripheral wall 8 of the concave portion 6 are both formed in an arc shape. Since the diameter may be reduced, a projection may be provided on the inner peripheral wall 8 of the concave portion 6 so that the outer peripheral portion of the ring-shaped member 3 and the inner peripheral wall 8 of the concave portion 6 can be engaged with each other.

[Brief description of the drawings]

FIG. 1 is a view showing a state in an initial assembly position in an embodiment of a pin-shaped member retaining mechanism according to the present invention;
(A) is a top view, (b) is an AA sectional view in (a).

FIG. 2 is a view showing a state where the pin-shaped member is prevented from falling off in the embodiment of the present invention at an assembly completion position;
(A) is a top view, (b) is an AA sectional view in (a).

FIG. 3 is a cross-sectional view showing one example of a pin-shaped member retaining mechanism of a conventional crawler belt link chain.

FIG. 4 is an explanatory diagram showing another application example of the pin-shaped member retaining mechanism of the present invention.

[Explanation of symbols]

 Reference Signs List 1 pin (first member) 2 link (second member) 3 ring-shaped member 4 concave groove 5 insertion hole 6 concave portion 7 bottom surface 8 inner peripheral wall

Claims (2)

[Claims] 1. A pin-shaped first member (1), an insertion hole (5) into which the first member (1) can be inserted, and a recessed portion formed around the opening of the insertion hole (5). 6) a ring-shaped member (3) fitted into a groove (4) provided around the first member (1);
The first member (1) is inserted into the insertion hole (5) of the second member (2), and in this state, the ring-shaped member () is fitted into the concave groove (4) of the first member (1). The pin-shaped member for regulating the relative movement of the first member (1) to the side opposite to the opening by bringing the end face of (3) into contact with the periphery of the opening of the insertion hole (5) in the recess (6). In the retaining mechanism, the ring-shaped member (3) is configured so as to be elastically expandable and contractable by cutting a part in the circumferential direction, and the ring-shaped member (3) is fitted into the recess (6). In this state, it is arranged so as to be rotatable around the axis (O) of the insertion hole (5), and its outer peripheral portion engages with the inner peripheral portion (8) of the recessed portion (6) to form the inner peripheral portion. Is an initial position where the diameter is equal to or larger than the diameter of the first member (1), and an inner peripheral portion thereof is smaller in diameter than the first member (1) and has a concave groove (4).
A retaining mechanism for a pin-shaped member, which can be rotationally displaced to a retaining position fitted in the inside. 2. The pin according to claim 1, wherein said ring-shaped member is held in said recess in said initial position by an elastic restoring force directed in a radially expanding direction. Mechanism for retaining the member.