JP6056810B2 - Method for manufacturing fluid pressure cylinder cover - Google Patents

Description

The present invention relates to a method of manufacturing a fluid pressure cylinder cover that is attached to the outside of a cylinder in order to protect the fluid pressure cylinder from contact with an obstacle.

  The background art will be described by taking a cylinder cover for a hydraulic cylinder used for an excavator work attachment as an example.

  As shown in FIG. 9, the excavator is mounted on a crawler-type lower traveling body 1 so that an upper swing body 2 can swing around an axis 0 that is perpendicular to the ground, and a work attachment A is attached to the upper swing body 2. Installed and configured.

  As shown in FIG. 10, the work attachment A includes a boom 3, an arm 4, a bucket 5, and hydraulic cylinders (boom, arm, and bucket cylinders) 6, 7, and 8 that operate them.

  In FIGS. 9 and 10, reference numeral 9 denotes a bucket link that converts the thrust of the bucket cylinder 8 into rotating power and transmits it to the bucket 5.

  Among the hydraulic cylinders 6 to 8 used in this work attachment A, for example, as shown in FIG. 10, a bucket cylinder 8 is provided with a cylinder cover 10 that protects the cylinder 8 from contact with the ground or an external object during excavation or traveling. It is attached in parallel with the cylinder 8 outside the cylinder.

  The structure of the conventional cylinder cover 10 will be described with reference to FIGS.

  The cylinder cover 10 is formed in a groove frame shape in which both sides in the width direction of the band plate material are bent inwardly in a U-turn shape, and covers the substantially full length portion of the cylinder 8 in the fully contracted state, and the tip portion thereof is a piston rod 8a It is attached to the front end portion (clevis) of this by a bolt 11.

  More specifically, a bolt through hole 12 (see FIG. 14) penetrating in the vertical direction is provided at the front end of the cylinder cover 10, while the piston rod front end facing the bolt through hole 12 as shown in FIGS. The female screw member 13 is fixed to the female screw member 13, and the bolt 11 is screwed into the female screw member 13 through the bolt through hole 12.

  Thus, the cylinder cover 10 is configured to slide integrally with the piston rod 8a to protect the cylinder 8 (particularly the piston rod 8a).

  As shown in FIGS. 11 to 13, a guide plate 14 slidably fitted into the cylinder cover 10 is attached to the outer periphery of the cylinder tube 8 b in parallel with the cylinder tube 8 b by a plurality of attachment bands 15. Is configured to slide integrally with the piston rod 8 a along the guide plate 14.

  In general, a reinforcing member (not shown) having a cross-sectional shape is attached to the outer surface of the cylinder cover 10 (the surface opposite to the cylinder 8) over almost the entire length of the cover.

  A basic configuration related to such a cylinder cover 10 is disclosed in Patent Documents 1 and 2, for example.

  Here, according to the cover mounting structure, the bolt 11 (exactly, the bolt head; the same shall apply hereinafter) is exposed to the outside, and thus is damaged by contact with the ground or an external object (hereinafter referred to as an “obstacle”). There is a fear.

  Therefore, a bolt protection wall 16 for protecting the bolt 11 is provided at the tip of the cylinder cover 10 as shown in the figure.

  The bolt protection wall 16 is formed in a generally U shape in plan view, and protects the bolt 11 from being in contact with an obstacle by surrounding the bolt 11 from three sides, the front end side of the cover and the left and right sides.

Patent No. 4038197 JP 2010-216557 A

  Conventionally, the bolt protection wall 16 is formed by bending a plate material as an independent part different from the cylinder cover 10, and as shown in FIG. Installed by welding in place.

  The hatched portions W1, W2, and W3 in FIG. 14 indicate the three welded portions of the bolt protection wall 16 to the cylinder cover 10. Among these, the bolt protection wall 16 is used for the cover front end side welded portion W1. In addition, it is necessary to ensure a surplus dimension S as a so-called welding allowance on the tip side.

  As a result, when the cylinder cover 10 protrudes toward the distal end side by the surplus dimension S and the bucket 5 shown in FIGS. 9 and 10 is rotated in the arrow direction of FIG. There was a possibility of approaching and interfering with the proximal side.

  In other words, since it is necessary to avoid this interference, there is a problem that the opening angle of the bucket 5 is limited and workability is deteriorated.

Therefore, the present invention provides a fluid pressure cylinder capable of solving the problem of interference between the cover front end portion and the bucket link while providing a bolt protective wall at the cover front end portion, eliminating the need for extra dimensions for welding the bolt protective wall. A method for manufacturing a cover is provided.

As a means for solving the above-described problems, in the present invention, one end of the piston rod is vertically moved to the tip of the piston rod so as to protect the fluid pressure cylinder by sliding integrally with the piston rod of the cylinder outside the fluid pressure cylinder. In a method of manufacturing a fluid pressure cylinder cover that is attached by a bolt in a direction and is provided with a bolt protection wall that protects the bolt from an external obstacle, a cover body that protects the fluid pressure cylinder, and a tip portion of the cover body A molding process for integrally forming a plate-shaped material including a bolt protective wall projecting in the distal direction of the main body, and a part of the material constituting the bolt protective wall on the side opposite to the fluid pressure cylinder And forming the bolt protection wall by bending it.

  According to this configuration, since the bolt protective wall is formed by bending the cover front end portion, as in the case of forming the bolt protective wall by welding other parts in the past, an extra dimension as a welding allowance on the cover front end side. Need not be secured.

  Accordingly, it is possible to avoid interference between the protruding portion on the front end side of the cover and the bucket link in the bucket opening posture, and to increase the bucket opening angle, that is, to improve workability.

  In addition, the bolt protection wall can be integrally formed as part of the cover (no separate parts are required), and the bolt protection wall can be formed at the same time when bending the cylinder cover, thereby reducing parts costs and processing costs. Can do.

Molding in the present invention, in the molding step, the bolt protective wall portion, and a front end wall portion continuous from the leading end side of the cover body, the material to include a side wall portion extending on the left and right sides from the front end wall portion In the processing step, a part of the material constituting the tip wall portion is bent perpendicularly to the cover body, and a portion constituting the both side walls portion of the material is bent with respect to the tip wall portion. It is desirable to form the bolt protection wall into a U-shape that surrounds the bolt from three sides by the tip wall and the left and right side walls by folding the cover body side so that it is perpendicular and both side walls are parallel. Claim 2).

  According to this configuration, since the bolt can be protected from three sides, the bolt protection effect against an obstacle is high.

In the above molding process, and molding the material so that the notch shape having a notch bending angle portion of the bolt protective wall portion is, in the processing step, some of the material constituting the bolt protective wall portion by bending, it is desirable that a cutout penetrating the bolt protective wall in the corner portions of the right and left sides of the bolt protective wall is formed by a notch above (claim 3).

  Thus, by forming a notch with a notch shape in the corner portion of the bolt protection wall, water or earth and sand that easily collects inside the bolt protection wall can be smoothly discharged from the notch, and the rust prevention effect can be enhanced.

  In addition, the notch can be easily formed at low cost simply by bending the bolt protective wall (without adding special processing such as drilling).

  According to the present invention, it is possible to solve the problem of interference between the cover front end portion and the bucket link by providing a bolt protective wall at the front end portion of the cover and eliminating the need for extra dimensions for welding the bolt protective wall.

1 is a perspective view of a cylinder cover and a hydraulic cylinder according to an embodiment of the present invention. FIG. 2 is a partially enlarged view of FIG. 1. It is the same top view. It is a top view before the bending process of a cylinder cover front-end | tip part. (a) is a perspective view of the state of FIG. 4, (b) is a perspective view after a bending process. It is a top view after the bending process of a cylinder cover front-end | tip part. It is the VII-VII sectional view taken on the line of FIG. FIG. 8 is an enlarged view of a portion surrounded by a broken line in FIG. 7. 1 is a schematic side view of a hydraulic excavator provided with a hydraulic cylinder to which the present invention is applied. FIG. 10 is a partially enlarged view of FIG. 9. It is a perspective view of the conventional cylinder cover and a hydraulic cylinder. FIG. It is the XIII-XIII sectional view taken on the line of FIG. It is a top view of a cylinder cover front-end | tip part.

  An embodiment of the present invention will be described with reference to FIGS.

  In the embodiment, a cylinder cover used for the bucket hydraulic cylinder (bucket cylinder) 8 in the work attachment A of the excavator shown in FIG. 9 is applied to the description of the background art.

  In this embodiment, the following points are the same as the prior art shown in FIGS.

  (i) The cylinder cover 20 is formed in a groove frame shape in which both sides in the width direction of the band plate material are bent inwardly in a U-turn shape, and covers the almost full length portion of the cylinder 8 in the fully contracted state, The point which is attached with the bolt 21 to the front-end | tip part (clevis) of piston rod 8a.

  (ii) Specifically, a bolt through hole 22 (see FIGS. 3 to 6) penetrating in the vertical direction is provided at the tip of the cylinder cover 20, and a female thread member is provided at the tip of the piston rod facing the bolt through hole 22. 23 (see FIG. 3) is fixed, and the bolt 21 is screwed into the female screw member 23 through the bolt through hole 22, so that the cylinder cover 20 slides integrally with the piston rod 8a and the cylinder 8 (particularly the piston rod 8a). Point configured to protect.

(iii) A guide plate 24 slidably fitted into the cylinder cover 20 is attached to the outer periphery of the cylinder tube 8 b in parallel with the cylinder tube 8 b by a plurality of attachment bands 25, and the cylinder cover 20 extends along the guide plate 24. A point configured to slide integrally with the piston rod 8a.

  (iv) Usually, a reinforcing member (not shown) having a cross-sectional shape is attached to the outer surface (the surface opposite to the cylinder 8) of the Linder cover 20 over the entire length of the cover.

  (v) A bolt protection wall 26 is provided at the tip of the cylinder cover 20 to protect the bolt 21 so that the bolt 21 (exactly the bolt head, hereinafter the same) does not come into contact with an obstacle and is damaged. point.

  In the embodiment, the bolt protection wall 26 is formed in a U-shape in plan view composed of a tip wall 26a and both side walls 26b, 26c, and is provided at the tip of the cover so as to surround the bolt 21 from the cover tip side and the left and right sides. It has been.

  The bolt protection wall 26 is formed integrally with the cover 20 as a part of the cylinder cover 20 and is bent when the cover is bent.

  That is, the cylinder cover 20 is formed by integrally providing the bolt protection wall 26 at the tip of the cover body 27 that protects the hydraulic cylinder 8.

  This cylinder cover structure will be described in detail with reference to FIGS.

  4 and 5A show the state of the material before bending the cylinder cover 20, that is, the state of the cylinder cover member 20 '.

  The cylinder cover member 20 'is integrally formed at the tip end portion of the cover main body 27 so that a bolt protection wall portion 26' that becomes a bolt protection wall 26 by bending is projected in the direction toward the tip end of the main body. .

  Two main body bending center lines (virtual lines) L1 and L2 are set on the cover body 27 symmetrically across the center line, and the cover main body 27 sets the main body bending center lines L1 and L2 in the bending process. It is bent into an inward U-turn shape at the center to form a groove frame shape.

  On the other hand, the bolt protection wall portion 26 ′ is formed by a distal end wall portion 26 a ′ continuous to the distal end side of the cover body 27, and both side wall portions 26 b ′ and 26 c ′ extending from the distal end wall portion 26 a ′ to the left and right sides. .

  The bolt protective wall portion 26 'has a tip wall bending center line L3 at the boundary with the cover body 27, and both side wall bending center lines L4 and L5 at the boundary between the tip wall portion 26a' and the side wall portions 26b 'and 26c', respectively. The distal end wall portion 26a 'is bent perpendicularly to the cover body 27 about the distal end wall bending center line L3, and both side wall portions 26b' and 26c 'are centered on both side wall bending center lines L4 and L5. It is bent toward the cover body so that it is perpendicular to the tip wall portion 26a 'and both side wall portions are parallel to each other.

  As a result, a U-shaped bolt protection wall 26 is formed that surrounds the bolt 21 from three directions in the assembled state with respect to the cylinder.

  Here, the bent corners of the bolt protection wall portion 26 ′ with respect to the cover body 27, that is, both the left and right sides of the boundary between the cover body 27 and the bolt protection wall portion 26 ′ (tip wall portion 26 a ′) as shown in FIG. The so-called “notch shape” includes arc-shaped (which may be U-shaped or V-shaped) cuts 28, 28.

  With this notch shape, the bolt protection wall portion 26 'is bent as described above to form the bolt protection wall 26, and as shown in FIGS. A notch 28 ′ is formed through the bolt protection wall 26 corresponding to 28.

  This notch 28 '(notch 28) is set to a size necessary and sufficient for discharging water and earth and sand inside the bolt protection wall to the outside.

  The both side walls 26b and 26c of the bolt protection wall 26 may be in a state of being bent. However, in order to securely maintain the integrity of the U-shaped bent shape and the cover body 27, FIG. As shown, it is desirable to weld the cover main body 27 (W2 and W3 indicate welded portions).

  According to this cylinder cover configuration, the following effects can be obtained.

  I. As shown in FIG. 14, in order to form the bolt protective wall 26 by bending the front end portion of the cover, as shown in FIG. It is not necessary to secure the surplus dimension S.

  That is, as shown in FIGS. 3, 6, and 7, there is no portion protruding from the bolt protective wall 26 toward the tip side.

  As a result, in the work attachment A of the hydraulic excavator shown in FIGS. 9 and 10, the protruding portion and the bucket link 9 can be prevented from interfering with each other in the bucket opening posture, and the bucket opening angle is increased, that is, the workability is improved. It becomes possible to make it.

  II. The bolt protective wall 26 can be integrally formed as a part of the cover 20 (no separate parts are required), and the bolt protective wall 26 can be formed at the same time when the cylinder cover 20 is bent. Can be reduced.

  III. Since the bolt 21 is enclosed from three sides by the U-shaped bolt protection wall 26, the bolt protection effect against an obstacle is high.

  IV. Since notches 28 'are formed by notching at the left and right corners of the bolt protection wall 26, water and dirt that tends to collect inside the bolt protection wall 26 are smoothly discharged from the notch 28' to the outside. The rust effect can be enhanced.

  In addition, the cutouts 28 'can be easily formed at low cost without special processing such as drilling.

Other embodiments
(1) The bolt protection wall 26 is not limited to the U-shape in plan view of the above-described embodiment, and may be arcuate, U-shaped, or V-shaped in plan view.

  (2) The present invention can be applied not only to the cylinder cover for the bucket cylinder 8 but also to the cylinder cover for the arm cylinder 7 and the boom cylinder 6 shown in FIGS.

  Also, not only hydraulic cylinders for work attachments of hydraulic excavators, but also cylinder covers attached to hydraulic cylinders for other work machines such as dismantling machines and crushers, and also for other hydraulic cylinders such as air cylinders. The same applies to the cylinder cover.

8 Hydraulic cylinder 8a Piston rod 8b Cylinder tube 20 Cylinder cover 21 Bolt 22 Bolt through hole 23 Member 24 Guide plate 25 Mounting band 26 Bolt protective wall 26a End wall of bolt protective wall 26b, 26c Same as the left and right side walls 26 'Bolt protective wall Part 26a 'tip wall part 26b', 26c 'left and right side wall part 27 cover body 28 notch 28' notch

Claims (3)

One end is attached to the tip of the piston rod with a vertical bolt so that the fluid pressure cylinder is protected by sliding integrally with the piston rod of the cylinder outside the fluid pressure cylinder, and the bolt is externally attached. In the method of manufacturing a hydraulic cylinder cover provided with a bolt protection wall that protects against obstacles of
A molding step of integrally molding a plate-shaped material including a cover main body that protects the fluid pressure cylinder, and a bolt protection wall that projects in the front end direction of the main body of the cover main body ;
A processing step of forming the bolt protection wall by bending a part of the material constituting the bolt protection wall portion to the side opposite to the fluid pressure cylinder ;
A method of manufacturing a fluid pressure cylinder cover , comprising: In the molding step, the bolt protection wall portion is molded with the material so as to include a distal end wall portion that continues to the distal end side of the cover body, and side wall portions that extend from the distal end wall portion to the left and right sides,
In the processing step, a part of the material constituting the tip wall portion is bent perpendicularly to the cover main body, and a portion constituting the both side wall portions of the material is perpendicular to the tip wall portion. Further, the bolt protection wall is formed in a U-shape that surrounds the bolt from three sides by the tip wall and the left and right side walls by bending the cover body side so that both side walls are parallel to each other. A manufacturing method of the fluid pressure cylinder cover according to Item 1. In the molding step, and molding the material so that the notch shape having a notch bending angle portion of the bolt protective wall portion,
In the processing step, and wherein said bolt protective wall portion by bending a part of the material constituting the, formed by cut the notches extending through the bolt protective wall in the corner portions of the right and left sides of the bolt protective wall A method of manufacturing a fluid pressure cylinder cover according to claim 1 or 2.

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