JPH05231407A - Polygonal flat cylinder - Google Patents

Abstract

PURPOSE:To provide a polygonal flat cylinder capable of being manufactured at low cost by simplifying a structure and applying compact design via an increase in compression. CONSTITUTION:A tube 2 has a rectangular cross sectional area, and a ratio of the short side to the long side is different. A head cover 3 and a rod cover 4 are fitted to both ends of the tube 2. Also, a piston 6 is internally coupled to the tube 2 in such a way as freely slidable. Furthermore, at least one of the head and rod covers 3 and 4 forms a part of, or is integrated with the tube 2. Also, the piston head 9 of the piston 6 comprises a head body 14 and cushion materials 15 fixed to both sides thereof. Lips 17 are laid around the cushion materials 15 in such a way as in slidable contact with the inner side of the tube 2.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a fluid pressure cylinder, and more particularly to a rectangular flat cylinder having a rectangular cross section.

[0002]

2. Description of the Related Art As a square flat cylinder of this type, the one disclosed in Japanese Utility Model Publication No. 61-16404 has been proposed. This rectangular flat cylinder has a substantially rectangular cross section,
Ribs are formed in the piston moving direction on the inner surface of the long side portion of the cylinder tube having a different ratio of the lengths of the short side and the long side. A rod cover and a head cover are arranged at both ends of the cylinder tube. The ribs prevent the weak long side of the cylinder tube from being deformed by the driving fluid pressure.

[0003]

That is, in the conventional rectangular flat cylinder, the rod cover, the tube, and the head cover are formed separately, and both covers are abutted against the end face of the tube and bolted, so that the tube is Weak against deformation due to internal pressure fluctuations. Therefore, the rib as described above is required. For this reason, the number of parts including the screws and the like is increased, and the volume is reduced, resulting in a large overall structure. Moreover, due to the ribs, the shape of the packing becomes a deformed shape along the rib shape, and this deformed packing has a problem that the manufacturing is not easy and the cost is high. Also, with respect to the ribs formed on the inner side, the effect becomes thin when the flatness is increased and the long sides become long. In such a case, even if the ribs are formed, the wall thickness of the long side of the tube is reduced. There is the problem of having to make it larger.

The present invention has been made by paying attention to the problems existing in the prior art as described above, and its purpose is to simplify the structure and increase the flatness to achieve compactness, and at low cost. It is to provide a square flat cylinder that can be manufactured.

[0005]

In order to achieve the above object, in the first invention, a tube having a rectangular cross section and different length ratios of its short side and long side, a head cover provided at both ends thereof, and The gist is that the rod cover and a piston that is slidably fitted in the tube are provided, and at least one of the head cover and the rod cover and the tube are integrally or integrally fixed.

In the second invention, the piston head of the piston is composed of a head body and a cushioning material fixed to both sides of the head body, and the inner peripheral surface of the tube is slidably contacted to the peripheral edge of the cushioning material. The point is that a lip is provided.

[0007]

With the above construction, since the entire circumference of the tube end is fixed to the cover, the deformation of the tube is extremely small.

On the other hand, the lip formed around the cushioning material is
Even if the tube is deformed and the diameter is expanded, the inner wall of the tube is pressed and a seal is secured.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment embodying the present invention will be described below with reference to FIGS. As shown in FIG. 1, a cylinder case 1 made of aluminum is composed of a tube 2, a head cover 3 and a rod cover 4. The tube 2 and the head cover 3 are integrally formed by extrusion and have a bottomed tubular shape as a whole. The tube 2 has a substantially rectangular cross section, and has a flat rectangular shape with a different ratio of the short side portion and the long side portion. The rod cover 4
A step is formed as a fitting portion on the periphery of the rod, and a rod hole 5 is formed at the center of the step. A piston rod 7 of a piston 6 is inserted into the rod hole 5 through a seal ring 8, and a piston head 9 is attached to the tube 2
Is movably inserted into. The fitting portion of the rod cover 4 is tightly fitted and fixed to the opening of the tube 2 by laser welding or an adhesive agent. Supply / discharge holes 10 and 11 are formed in the head cover 3 and the rod cover 4, respectively. The supply / discharge hole 10 of the head cover 3 has a cylinder chamber 12 on the head side.
In addition, the supply / discharge hole 11 of the rod cover 4 communicates with the cylinder chamber 13 on the rod side. Both supply / discharge holes 10 and 11 are perforated to a certain depth from the side surfaces of both covers 3 and 4, and are similarly perforated from the surface in contact with the cylinder chambers 12 and 13 so that the two are electrically connected to form a flow path.

The head body 1 is attached to the tip of the piston rod 7.
4 is integrally formed in a brim shape. This head body 14
A cushioning material 15 made of rubber is fixed to both surfaces of the same by pins 16. The cushioning material 15 can absorb the impact of the head body 14 hitting the covers 3 and 4 when the piston 6 reciprocates. Further, a lip 17 having a sealing structure is formed on the peripheral edge of the cushioning material 15. Lip 1
The tips of 7 are bent in the respective directions of the covers 3 and 4, and even if the tube 2 is deformed and the diameter thereof is expanded, the bent portion extends accordingly and presses the inner wall of the tube 2 to secure a seal. Moreover, a dedicated packing ring is not required, and the number of parts can be reduced.

FIG. 3 shows a case where the rectangular flat cylinder of this embodiment is used as a drive power source for the slide table 18. The axial position of the piston rod 7 can be set low by arranging the rectangular flat cylinder with the long side portion 19 horizontal, so that it can be installed in the equipment without changing the load height of the table 18.

As described above, since the cylinder shape is rectangular and flat, the load of the driving fluid on the tube 2 is maximized at the center of the long side portion 19 and the long side portion 19 is deformed outward. FIG. 5 shows such a state, and the degree of deformation is plotted as a strain amount δ. As shown in FIG. 4, the horizontal axis is the position l ₀ of the long side portions 19 and 23,
(A) is a characteristic corresponding to the conventional example (a) in which the head cover 20 and the rod cover 21 are screwed to the tube 22. On the other hand, (B) is a characteristic indicating the amount of strain in this embodiment (b). As shown in the graph, it can be seen that the strain amount of this embodiment is halved compared to the conventional example. Moreover, whether the cover is integrally formed at the end of the long side portion 19,
The amount of strain is zero because they are bonded. In this way, since the amount of distortion can be reduced, the flatness ratio (long side / short side)
Not only can it be increased from the conventional value of 2.0 to 5.0, but a reinforcing means such as a rib is not required, so that the internal volume can be increased, and as a result, the size can be reduced.
Besides, Since parts such as screws are not required, the number of parts is reduced, and the manufacturing is easy.

The present invention is not limited to the configuration of the above-described embodiment, but may be configured as follows, for example, without departing from the spirit of the invention. (1) In the above embodiment, the supply / discharge holes 10 and 11 are formed in each of the head cover 3 and the rod cover 4, but as shown in FIG. 6, a bypass 25 is formed in the tube 24 to form the rod side cylinder chamber 13. And one of the supply / discharge holes 26 is connected. Therefore, the supply / discharge holes 26 and 27 can be gathered in one direction, and there is an effect that a space is not required during use.

(2) The head cover and the rod cover are separated from the tube and fixed to the tube by adhesion or welding. (3) Form the supply / discharge holes 28 and 29 in the tube as shown in FIG.

[0015]

According to the present invention, since at least one cover is integrally or integrally fixed, the number of parts can be reduced, cost can be reduced, and flatness and compactness can be improved.

On the other hand, the lip on the peripheral edge of the cushioning material fixed to the head body has the effect of reducing the number of parts and reducing the cost.

[Brief description of drawings]

FIG. 1 is a longitudinal sectional view showing an embodiment of a rectangular flat cylinder embodying the present invention.

FIG. 2 is a transverse sectional view showing an embodiment of a rectangular flat cylinder.

FIG. 3 is a perspective view showing a state in which a rectangular flat cylinder is also used as a drive source for the slide table.

FIG. 4 is a cross-sectional view comparing an example of the present invention with a conventional example.

FIG. 5 is a graph showing the distortion amounts of the embodiment of the present invention and the conventional example,
It is a characteristic view comparing the position of the tube in the axial direction with the horizontal axis.

FIG. 6 is a vertical sectional view showing another example of the present invention.

[Explanation of symbols]

2 tubes, 3 head covers, 4 rod covers,
6 pistons, 9 piston heads, 14 head bodies, 15 cushioning materials, 17 lips.

Claims (2)

[Claims] 1. A tube having a rectangular cross section and having different length ratios of its short side and long side, head covers and rod covers provided at both ends thereof, and a piston slidably fitted in the tube. And a tube that is integrally or integrally fixed to at least one of the head cover and the rod cover. 2. A piston head of the piston comprises a head body and a cushioning material fixed to both sides of the head body, and a lip for slidingly contacting an inner peripheral surface of the tube is provided on a peripheral edge of the cushioning material. The rectangular flat cylinder according to claim 1, characterized in that.