JP5497869B2 - Clip mounting device - Google Patents

Description

The present invention relates to a clip mounting device for fixing a piston pin provided on a piston of an engine.

A piston pin connecting the piston and the connecting rod is fixed in the axial direction by a clip. Various devices for attaching the clip to the piston pin hole are known (see, for example, Patent Document 1).
FIG. 9 illustrates such a conventional clip attachment device. The piston pin 114 is inserted into the pin hole 116 of the piston 110, and both ends in the axial direction are fixed by C-shaped clips 120. The C-shaped clip 120 is fitted into a clip groove 118 provided in the pin hole 116. As shown on the right side of the figure, the clip 120 is attached by holding the clip 120 in an inclined manner on a jig 140 inserted into the shaft hole of the piston pin 114 in advance and inserting it into the pin hole 116 while reducing the diameter. After the tip portion is fitted into the clip groove 118, for example, by further extruding the outer peripheral portion of the jig 140 which is movable in the axial direction, the clip 120 is rotated upright with the fitting portion as a fulcrum. The whole is fitted into the clip groove 118 while being expanded in diameter.

JP 2006-88238 A

By the way, the clip 120 cannot be inserted into the pin hole 116 unless the outer diameter when the diameter is reduced is equal to or smaller than the inner diameter of the pin hole 116. On the other hand, the C-shaped clip is reduced in diameter by narrowing the interval between the mating ports at both ends facing the open portion, so that the diameter reduction limit is reached when the mating ports are in contact. Therefore, when there is a slight error in the outer diameter of the clip 120 and the outer diameter of the diameter reduction limit is larger than the inner diameter of the pin hole 116, the clip 120 and the pin hole 116 are rotated when the clip 120 is rotated in the pin hole 116. Since the inner peripheral surface cannot interfere and cannot stand upright and cannot be fitted into the clip groove 118, it is impossible to mount the clip 120, and the clip 120 must be replaced with another one and the operation must be performed again.
Therefore, the present application aims to provide an apparatus that can be attached even if the outer diameter is slightly different.

In order to solve the above-mentioned problem, the clip mounting device according to claim 1 inserts the C-shaped clip (20) in a reduced diameter into the pin hole (16) of the piston (10), In the clip mounting device fitted into the clip groove (18),
On the central axis (L) of the pin hole (16),
Providing a first pressing part (60) and a second pressing part (70) for pressing from both sides of the clip (20) inserted into the pin hole (16);
The first pressing portion (60) and the second pressing portion (70) are characterized in that the mating ports (22, 22) of the clip (20) are deformed so as to open in opposite directions.

According to a second aspect of the present invention, in the first aspect, the first pressing portion (60) and the second pressing portion (70) are opposite to each other across the central axis (L) of the pin hole (16). And each is arranged in parallel with the central axis (L).

According to a third aspect of the present invention, in the second aspect of the present invention, the first pressing portion (60) and the second pressing portion (70) are opposite to each other in the vicinity of each joint (22) of the clip (20). It is characterized by pushing in the direction.

According to a fourth aspect of the present invention, in the third aspect of the present invention, an insertion shaft (40) that supports the first pressing portion (60) so as to advance and retract is provided.
The first pressing portion (60) protrudes from the tip of the insertion shaft (40),
Of the clip (20) that is held at a reduced diameter in the pin hole (16),
Positioned on the side approaching the second pressing portion (70), the first pressed portion (28a) that forms the vicinity of one of the joints (22) is pressed by the first pressing portion (60),
A portion located on the side away from the second pressing portion (70) is pressed by the tip of the insertion shaft (40).

According to a fifth aspect of the present invention, in the fourth aspect of the invention, a backup shaft (50) that supports the second pressing portion (70) so as to advance and retreat is provided.
The tip of the backup shaft (50) is located facing the inner edge of the clip groove (18),
While fitting a part of the first pressure-receiving portion (28a) pressed by the first pressing portion (60) into the clip groove (18),
The second pressing part (70) presses the second pressure-receiving part (28b) forming the vicinity of the other joint (22) beyond the clip groove (18).

According to the invention described in claim 1,
When the clip (20) is pressed from both sides by the first pressing part (60) and the second pressing part (70), the mating ports (22, 22) of the clip (20) are deformed so as to open in opposite directions. . For this reason, the clip (20) is deformed three-dimensionally, and the diameter is reduced so that the mating ports (22, 22) are deformed in different planes.
For this reason, the diameter of the clip (20) varies because the diameter of the mating opening (22, 22) can be further reduced from the diameter reduction limit of the conventional example as compared with the conventional example in which the diameter is reduced in the same plane. Therefore, even if the conventional diameter reduction limit outer diameter (D4) becomes larger than the inner diameter (D1) of the pin hole (16), it can be further reduced in diameter and inserted into the pin hole (16).

According to the invention described in claim 2,
A 1st press part (60) and a 2nd press part (70) are arrange | positioned on the opposite side on both sides of the central axis (L) of a pin hole (16), and each is arrange | positioned in parallel with a central axis (L). Therefore, when the first pressing part (60) and the second pressing part (70) are pressed from the opposite sides, each presses the opposite side portion of the clip (20) across the central axis (L). The deformation of the clip (20) can be increased.

According to the invention described in claim 3,
The first pressing portion (60) and the second pressing portion (70) serve as a first pressure-receiving portion (28a) and a second pressure-receiving portion (28b) that are in the vicinity of each joint (22) of the clip (20). Since the clips are pushed in the opposite directions, the clip (20) is easily opened and deformed in the opposite directions along the central axis (L) with the opening (21) in between.

According to the invention described in claim 4,
Since the first pressing portion (60) is protruded from the insertion shaft (40), one of the clips (20) that is held at a reduced diameter in the pin hole (16) and protrudes forward (in the pressing direction). The first pressed portion (28a) in the vicinity of the abutment (22) is pressed by the first pressing portion (60) and moved toward the clip groove (18), and tilted backward (in the opposite pressing direction). It is possible to move the clip (20) while rotating the entire clip (20) by pressing the portion with the tip of the insertion shaft (40).

According to the invention described in claim 5,
Since the tip of the backup shaft (50) faces the inner edge of the clip groove (18), a part of the first pressure-receiving part (28a) pressed by the first pressing part (60) is clipped. (18) can be fitted,
Since the second pressing part (70) presses the second pressed part (28b) that forms the vicinity of the other joint (22) beyond the clip groove (18), the first pressed part (28a) The second pressure-receiving part (28b) can be deformed in the direction of the central axis (L), and at the same time, a part of the clip (20) can be fitted into the clip groove.

Cross section of piston Diagram explaining the diameter reduction of the clip The figure shown in the state which decomposed | disassembled the clip attachment apparatus with respect to the piston of FIG. The figure which shows the state just before the attachment of the clip by the insertion shaft Diagram showing clip mounting process Same as above Same as above Same as above Sectional view showing a conventional example

Hereinafter, an embodiment will be described based on the drawings.
FIG. 1 is a cross-sectional view of a piston, and the piston 10 is connected by a connecting rod 12 and a piston pin 14.

A pin hole 16 for the piston pin 14 is formed in the piston 10 so as to penetrate in the direction perpendicular to the axis of the connecting rod 12. The piston pin 14 is fixed in the axial direction by a clip 20 fitted in a clip groove 18 formed in the pin hole 16.

The clip 20 is attached to the clip groove 18 by a clip attachment device described later. At this time, the clip 20 is inserted into the pin hole 16 in a state of being reduced in diameter and inclined, as indicated by phantom lines in the drawing, and the clip 20 is inserted into the clip groove 18 after the inclined tip side is fitted. 20 is raised vertically so that the whole fits into the clip groove 18.

2A and 2B are diagrams for explaining the diameter reduction of the clip 20. A is an enlarged cross-sectional view of the pin hole 16 portion of the piston as A, and B is a normal state of the clip 20 (the diameter is reduced without applying a force for diameter reduction). The figure which shows the clip 20 in the center axis line direction in the state which is not), C is the same figure at the time of diameter reduction.

As shown in FIG. 2A, the pin hole 16 has an inner diameter D1, and the diameter at the bottom of the clip groove 18 is D2, which is larger than D1. The difference between D2 and D1 is twice the depth d of the clip groove 18.

As shown in FIG. 2B, the clip 20 in the normal state is a metal member having a substantially C-shape and rich in elasticity, and a pair of mating ports 22 that are circumferential end portions provided in a part of the circumferential direction. Is located. The diameter of the clip 20 is reduced by narrowing the interval S between the mating ports 22. Of the clip 20, the vicinity of the mating port 22 on one side is defined as a first pressure-receiving portion 28a, and the other side is defined as a second pressure-receiving portion 28b.

One of these pressure-receiving portions is in contact with either a first pressing portion 60 or a second pressing portion 70 described later, and the other pressing portion is in contact with the other. In the following description, it is assumed that the first pressing portion 60 is in contact with the first pressed portion 28a and the second pressing portion 70 is in contact with the second pressed portion 28b.
The width w sandwiched between the inner periphery 24 and the outer periphery 26 of the clip 20 is wider than the depth d of the clip groove 18 (A in FIG. 2), and the outer diameter D3 of the outer periphery 26 that does not reduce the diameter is the diameter of the clip groove 18. Greater than D2.

C in FIG. 2 shows a state at the time of maximum diameter reduction in which a pair of mating ports 22 are in contact, and the outer diameter at this time is the diameter reduction limit outer diameter D4. The clip 20 cannot be reduced in diameter smaller than the diameter reduction limit outer diameter D4.

Next, the clip mounting device will be described.
FIG. 3 is an exploded view of the clip attachment device for attaching the clip 20 to the piston 10 of FIG.

The clip mounting device includes a clip holder 30 that is brought into contact with one end of the pin hole 16 on the central axis L of the pin hole 16, an insertion shaft 40 that advances and retreats into the clip holder 30 and the pin hole 16, and A backup shaft 50 that advances and retracts into the pin hole 16 from the other end side is provided.

FIG. 4 shows a state immediately before the clip 20 is attached by the insertion shaft 40, the clip holder 30 is brought into contact with one end side opening of the pin hole 16 on the side surface of the piston 10, and the backup shaft 50 is advanced into the pin hole 16. In addition, a state in which the insertion shaft 40 is retracted from the clip holder 30 is shown.

The clip holder 30 has a cylindrical shape, and the shaft hole 32 has an inner diameter that is equal to or slightly smaller than the inner diameter D1 of the pin hole 16, and comes into contact with the opening on one end side of the pin hole 16 on the side surface of the piston 10. The hole 32 coincides with the pin hole 16. The clip 20 is supplied into the shaft hole 32 by a clip supply device (not shown).

At this time, the outer diameter D3 (B in FIG. 2) of the clip 20 in the normal state is approximately the same as or slightly larger than the diameter D2 (A in FIG. 2) at the bottom of the clip groove 18. Since it is larger than the diameter (D1), the diameter of the shaft hole 32 is reduced to a predetermined size from D1 to D4 (C in FIG. 2), and is held in an inclined state.

The clip 20 is held with the abutment 22 facing the piston 10 side. In this example, when the clip 20 is attached to the clip groove 18 of the piston 10, the abutment 22 faces downward and is located on the backup shaft 50 side. It has become. However, the direction of the abutment 22 may be directed toward the insertion shaft 40 in the clip holder 30 and may be directed upward when attached to the clip groove 18.

The insertion shaft 40 is a shaft cylindrical member that fits into the shaft hole 32, and is movable back and forth along the direction of the central axis L of the pin hole 16. When the insertion shaft 40 moves forward (operation toward the center of the piston 10), the clip 20 in the shaft hole 32 is pushed out into the pin hole 16.

The insertion shaft 40 is provided with a shaft hole 42 opened toward the piston 10, and a first pressing portion 60 is provided in the shaft hole 42 so as to be able to advance and retreat, and is moved toward the piston 10 by a first spring 62. It is biased in the protruding direction. The first pressing portion 60 is a member that is pressed against the clip 20 to push the clip 20 into the clip groove 18.

The backup shaft 50 is a member for restricting the position of the clip 20 pushed by the insertion shaft 40, enters the pin hole 16, and can freely advance and retract along the central axis L direction. When the pin 20 has advanced into the pin hole 16, the tip faces the inner edge (center side of the piston 10) of the clip groove 18 and stops (this position is called the most advanced position), and the clip 20 pushed into the insertion shaft 40. The leading end of each is guided into the clip groove 18.

The backup shaft 50 is provided with a shaft hole 52 opened toward the piston 10 side, and a second pressing portion 70 is provided in the shaft hole 52 so as to be able to advance and retreat. The second spring 72 moves toward the piston 10 side. It is biased in the protruding direction. The second pressing part 70 is located on the opposite side of the first pressing part 60 with the piston 10 in between, and the first pressing part 60 and the second pressing part 70 are arranged in parallel to the central axis L, respectively. Further, as shown in FIG. 5, the first pressing portion 60 and the second pressing portion 70 are located on opposite sides of the center axis L of the pin hole 16, in other words, in a direction orthogonal to the center axis L of the pin hole 16. They are offset from each other.

When the backup shaft 50 is at the most advanced position, the second pressing portion 70 further protrudes toward the clip holder 30 and abuts against a part of the clip 20 that is pushed in by the insertion shaft 40, and the pushing movement of this portion is clipped. This is a member for temporarily stopping in front of the groove 18 (on the clip holder 30 side) (this stop position is referred to as a temporary stop position).

The first spring 62 and the second spring 72 have substantially the same strength and are stronger than the spring of the clip 20 as a leaf spring. The first spring 62 and the second spring 72 push the clip 20 without being compressed, and The part can be elastically deformed.

In this way, as shown in FIG. 2B, the first pressing portion 60 presses the portion 28 a close to the mating port 22 on one side of the clip 20, and the second pressing portion 70 corresponds to the other side portion of the clip 20. 28b will be pushed.

Next, the operation will be described. 5-8 is a figure which shows the attachment process of the clip 20, and is a figure simplified and shown from the downward direction (arrow E direction) of FIG. 3, respectively.
First, in FIG. 5, the clip holder 30 is pressed against the side surface of the piston 10 to advance the backup shaft 50.

At this time, in the clip holder 30, the clip 20 is inclined in advance, and the open portion 21 (abutment 22) is faced downward so as to protrude toward the backup shaft 50 side.
In this state, the backup shaft 50 stops at the most advanced position where the tip faces the inner edge of the clip groove 18, and the second pressing portion 70 projects beyond the clip groove 18 to a position close to the clip 20. Is in the state of FIG.

Subsequently, when the insertion shaft 40 is advanced, the first pressing portion 60 comes into contact with the first pressure-receiving portion 28a, pushes the entire clip 20 into the pin hole 16 from the clip holder 30, and eventually the second pressure-receiving portion 28b. Comes into contact with the second pressing portion 70. At this time, the upper side of the clip 20 is inclined toward the first pressing portion 60 side, but since this portion is pushed by the distal end portion of the insertion shaft 40, the posture of the clip 20 gradually changes so as to stand upright.
The state of the clip 20 and the first pressing portion 60 thus changed is shown in FIG. 6, and the clip 20 at this stage does not reach the clip groove 18.

Subsequently, when the insertion shaft 40 is further advanced, FIG. 7 is obtained. As shown in the enlarged portion of FIG. 7, in the clip 20, the second pressure-receiving portion 28 b cannot move forward when the second pressing portion 70 comes into contact, and stops at the temporary stop position. The distal end of the insertion shaft 40 has not yet contacted the second pressed part 28b.
On the other hand, since the first pressed portion 28a is not prevented from moving by the second pressing portion 70, the first pressed portion 28a is pushed by the first pressing portion 60 and continues to advance, and eventually reaches the clip groove 18 and fits into the clip groove 18. To do.

For this reason, in the clip 20, the first pressure-receiving portion 28a and the second pressure-receiving portion 28b receive reverse forces by the first pressing portion 60 and the second pressing portion 70, and an opening e is generated in the central axis L direction. Thus, it becomes a twisted state.
As described above, when the clip 20 is twisted and deformed in the central axis L direction (also in the central axis direction of the clip 20), the diameter is further reduced.

In addition, the diameter reduction is performed by deformation in a three-dimensional direction. For this reason, when the entire clip 20 is reduced in diameter only within the same plane as in the conventional example, the reduced diameter limit outer diameter D4 (C in FIG. 2) in which both the abutments 22 abut each other is reduced. However, the diameter can be further reduced beyond the limit.
That is, since the mating ports 22 and 22 are in different planes, the mutual contact state that becomes the limit of the diameter reduction does not occur.

Subsequently, as shown in FIG. 8, when the insertion shaft 40 is pushed out until its tip coincides with the outer edge of the clip groove 18, the second pressure-receiving portion 28b is moved to the second portion as shown in the enlarged portion in the figure. It pushes back onto the clip groove 18 against the second spring 72 together with the pressing portion 70.

Then, the second pressed part 28b moves onto the clip groove 18, and the first pressed part 28a and the entire second pressed part 28b are changed from the twisted state to the initial state on the same plane and fitted into the clip groove 18. At the same time, the clip 20 is turned upright with the fitting portion as a fulcrum, and the entire clip 20 overlaps with the clip groove 18. Match.

At this time, the distal ends of the first pressing portion 60 and the second pressing portion 70 are flush with the distal ends of the insertion shaft 40 and the backup shaft 50, respectively, and the distal end of the insertion shaft 40 is at the outer edge of the clip groove 18. Since the front end of the backup shaft 50 faces the inner edge of the clip groove 18, the entire clip 20 can be quickly fitted into the clip groove 18.

Thereby, the attachment of the clip 20 to the clip groove 18 is completed. Subsequently, when the insertion shaft 40 and the backup shaft 50 are moved backward together with the first pressing portion 60 and the second pressing portion 70 and escaped from the pin hole 16, the piston 10 can be taken out.
Thereafter, if another clip 20 is reloaded into the clip holder 30, the next attachment can be performed in the same procedure.

In this way, the clip 20 is reduced in diameter so that the mating ports 22 and 22 are deformed in different planes, thereby comparing with the conventional example in which the mating ports 22 and 22 are reduced in diameter in the same plane. Since the diameter of the clip 20 can be further reduced than the diameter reduction limit of the example, even if the diameter of the clip 20 varies and the conventional diameter reduction limit outer diameter D4 becomes larger than the inner diameter D1 of the pin hole 16, this is further increased. The diameter can be reduced and the pin hole 16 can be inserted.

Moreover, since the 1st press part 60 and the 2nd press part 70 are arrange | positioned on the opposite side of the clip 20 along the center axis L of the pin hole 16, and each is arrange | positioned in parallel with the center axis L, the 1st When the pressing part 60 and the second pressing part 70 are pressed from the opposite sides, the first pressing part 60 and the second pressing part 70 are displaced to the opposite side across the central axis L of the pin hole 16 (FIG. 5). Each can press the opposite side of the clip 20 to increase the deformation of the clip 20.

Further, the first pressing part 60 and the second pressing part 70 push the first pressed part 28a and the second pressed part 28b in the vicinity of the respective joints 22 of the clip 20 in the opposite directions, so that the clip 20 It is easy to deform by opening in opposite directions along the central axis L across the opening 21.

Moreover, since the 1st press part 60 was protruded from the insertion shaft 40, among the clips 20 diagonally reduced-diameter-maintained within the pin hole 16, the one 22 vicinity vicinity part which protrudes ahead (press direction) The first pressure-receiving portion 28a forming the above is pressed by the first pressing portion 60 and moved toward the clip groove 18, and the portion inclined backward (in the opposite pressing direction) is pressed by the tip of the insertion shaft 40 to clip The whole 20 can be moved while being rotated.

Furthermore, since the tip of the backup shaft 50 is positioned facing the inner edge of the clip groove 18, a part of the first pressure-receiving portion 28 a pressed by the first pressing portion 60 is fitted into the clip groove 18. As well as
Since the second pressing portion 70 presses the second pressure-receiving portion 28b that forms the vicinity of the other abutment 22 beyond the clip groove 18, the first pressure-receiving portion 28a and the second pressure-receiving portion 28b are center axes. Simultaneously with the deformation in the L direction, a part of the clip 20 can be fitted into the clip groove 18.

In the above example, the clip 20 on one side before the piston pin 14 is attached is attached. However, the clip 20 may be attached to the clip groove 18 on the other side after the piston pin 14 is attached. it can. In this case, the outer diameter of the backup shaft 50 may be made smaller than the inner diameter of the shaft hole of the piston pin 14 so as to be able to advance and retract through the piston pin 14.

Further, even when a plurality of types of clips 20 having slightly different outer diameters are used, there is no need to prepare a dedicated clip holder 30 suitable for each, and a common clip holder 30 may be used. The versatility of is increased.

10: piston, 14: piston pin, 16: pin hole, 18: clip groove, 20: clip, 30: clip holder, 40: insertion shaft, 50: backup shaft, 60: first pressing part, 70: second pressing Part, L: central axis

Claims (5)

In the clip attachment device for inserting the C-shaped clip (20) into the pin hole (16) of the piston (10) with a reduced diameter and fitting it into the clip groove (18) in the pin hole (16),
On the central axis (L) of the pin hole (16),
Providing a first pressing part (60) and a second pressing part (70) for pressing from both sides of the clip (20) inserted into the pin hole (16);
A clip mounting characterized by deforming the mating ports (22, 22) of the clip (20) to open in opposite directions by the first pressing portion (60) and the second pressing portion (70). apparatus. The first pressing portion (60) and the second pressing portion (70) are disposed on opposite sides of the central axis (L) of the pin hole (16), and each of the first pressing portion (60) and the second pressing portion (70) and the central axis (L). The clip mounting device according to claim 1, wherein the clip mounting device is arranged in parallel. The said 1st press part (60) and the 2nd press part (70) pushed each mating part (22) vicinity part of the said clip (20) to a mutually reverse direction, The said 2nd press part (70) characterized by the above-mentioned. Clip mounting device. An insertion shaft (40) that supports the first pressing portion (60) so as to freely advance and retract is provided,
The first pressing portion (60) protrudes from the tip of the insertion shaft (40),
Of the clip (20) that is held at a reduced diameter in the pin hole (16),
Positioned on the side approaching the second pressing portion (70), the first pressed portion (28a) that forms the vicinity of one of the joints (22) is pressed by the first pressing portion (60),
The clip attachment device according to claim 3, wherein a portion located on the side away from the second pressing portion (70) is pressed by a tip of the insertion shaft (40). A backup shaft (50) for supporting the second pressing portion (70) so as to freely advance and retract,
The tip of the backup shaft (50) is located facing the inner edge of the clip groove (18),
While fitting a part of the first pressure-receiving portion (28a) pressed by the first pressing portion (60) into the clip groove (18),
The said 2nd press part (70) presses the 2nd to-be-pressed part (28b) which makes the other said joint (22) vicinity part beyond the said clip groove | channel (18). 4. The clip attachment device described in 4.

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