JP2710724B2 - Square flat cylinder - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

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

[0002]

2. Description of the Related Art As a rectangular flat cylinder of this type, a cylinder shown in Japanese Utility Model Publication No. 61-16404 has been proposed. This rectangular flat cylinder has a substantially rectangular cross section,
A rib is formed in the moving direction of the piston on the inner surface of the long side of the cylinder tube having a different length ratio between the short side and the long side. A rod cover and a head cover are provided at both ends of the cylinder tube. The rib prevents the weak 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 surface of the tube and are bolted. Vulnerable to deformation due to internal pressure fluctuation. For this reason, a rib as described above is required. For this reason, the number of parts including screws and the like is increased, and the volume is reduced. As a result, the overall structure is increased. In addition, the shape of the packing is irregular along the rib shape due to the ribs, and there is a problem that the irregular packing is not easy to manufacture and the cost is high. Also, the effect of the ribs formed on the inner side is reduced when the long side portion is increased by increasing the flattening ratio. In such a case, even if the ribs are formed, the wall thickness of the long side portion of the tube is reduced. There is a problem that it must be increased.

The present invention has been made in view of such problems existing in the prior art, and has as its object to simplify the structure, increase the flattening rate, reduce the size, and reduce the cost. An object of the present invention is to provide a square flat cylinder that can be manufactured.

[0005]

In order to achieve the above object, according to a first aspect of the present invention, a tube having a rectangular cross section and having different ratios of the lengths of its short side and long side, and end covers provided at both ends thereof are provided. And a piston that is slidably fitted in the tube, wherein the piston head of the piston has a head body, and the piston is fixed to both sides of the head body in the piston moving direction, and the piston is a tube. It is made of a cushioning material which comes into contact with the end cover when moved to the end, and the periphery of the cushioning material is opposed to the periphery from the same periphery.
When it is formed to extend diagonally to the end cover side
Deformed to the inside of the tube by the inner peripheral surface of the tube
The gist of the invention is that a lip is provided for sliding contact with the inner peripheral surface .

In the second invention, in addition to the first invention,
One end cover is integral with or integral with the tube
And partitioned by the piston
One pair of supply and discharge holes for supplying and discharging the working fluid to and from the cylinder chamber
The main point is that the opening is concentrated on the end cover .

[0007]

According to the above construction, in the first aspect, the piston is
Move to the end of the tube and the piston head is the end cover
Stops on both sides of the head body in the piston movement direction
The shock is reduced by the applied cushioning material. Also, loose
The lip on the periphery of the impact
Even if the tube is deformed and expanded, the inner wall of the tube is
Characteristics are secured.

[0008] In the second invention, one of the end covers is connected to the end cover.
The tube is integrated with or integral with the tube.
The deformation of the blade is extremely small. Also, add working fluid to the cylinder chamber.
Concentrate the pair of supply / discharge holes for supply / discharge on one end cover
The piping for supplying and discharging the working fluid to the cylinder
You can focus.

[0009]

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

At the tip of the piston rod 7, a head body 1 is provided.
4 are integrally formed in a flange shape. This head body 14
A cushioning material 15 made of rubber is fixed to both surfaces by pins 16. The cushioning material 15 can reduce the impact of the head body 14 hitting the covers 3 and 4 when the piston 6 reciprocates. A lip 17 having a seal structure is formed on the periphery of the cushioning material 15. Lip 1
The tip of 7 is bent in the directions of the covers 3 and 4, respectively, so that even if the tube 2 is deformed and its diameter is expanded, the bent portion extends along with it, and the inner wall of the tube 2 is pressed down to secure a seal. In addition, a dedicated packing ring is not required, and the number of parts can be reduced.

[0011] FIG. 3 shows a case where a rectangular flat Cylinders of this example was a driving power source of the slide <br/> id table 18. By arranging the rectangular flat cylinder with the long side portion 19 horizontal, the axial position of the piston rod 7 can be set low, so that the table 18 can be installed on the apparatus without changing the load height.

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 tends to deform the long side portion 19 outward. FIG. 5 shows this state, in which the degree of deformation is plotted as a distortion amount δ. As shown in FIG. 4, the horizontal axis is the position l ₀ of the long sides 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 showing the distortion amount of the embodiment (b). As shown in the graph, it can be seen that the distortion amount of the present embodiment is halved compared to the conventional example. Moreover, whether the cover is formed integrally at the end of the long side portion 19,
The amount of distortion is zero due to bonding. Thus, since the amount of distortion can be reduced, the flattening ratio (long side / short side)
Not only can be increased from the conventional value of about 2.0 to 5.0, but also 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.
Moreover. Since components such as screws are not required, the number of components is reduced, and production is facilitated.

The present invention is not limited to the configuration of the above 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. However, as shown in FIG. 6, a bypass 25 is formed in the tube 24 and the cylinder chamber 13 on the rod side is formed. And one of the supply / discharge holes 26. For this reason, the supply and discharge holes 26 and 27 can be gathered in one direction, and there is an effect that a space is not required when using.

(2) Separate the head cover and rod cover from the tube and fix them to the tube by bonding or welding. (3) The supply and discharge holes 28 and 29 are formed in the tube as shown in FIG.

[0015]

As described above in detail, according to the first invention,
If the piston moves to the end of the tube,
Can reduce the impact of the body hitting the end cover
At the same time, even if the diameter of the tube expands, it can secure the sealing
The effect is that the number of parts can be reduced and the cost can be reduced .

According to the second invention, the effect of the first invention is obtained.
In addition, the number of parts can be reduced and cost can be reduced.
Also, since the amount of tube distortion can be reduced,
The flattening rate and compactness can be improved
In addition, the sealability is further improved in combination with the piston of the first invention.
More can be secured. In addition, supply and drain holes are
To supply and discharge fluid to and from the cylinder.
Pipes can be concentrated, and the pipes can be easily formed .

[Brief description of the drawings]

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

FIG. 2 is a cross-sectional view showing one embodiment of a rectangular flat cylinder.

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

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

FIG. 5 is a graph showing the amount of distortion between the embodiment of the present invention and the conventional example.
FIG. 6 is a characteristic diagram in which the position in the axial direction of the tube is compared with the horizontal axis.

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

[Explanation of symbols]

2 Tube, head cover as 3 end cover , rod cover as 4 end cover, 6 piston, 9 piston head, 14 head body, 15
Cushioning material, 17 lips , 28, 29 supply and discharge holes .

Claims (2)

(57) [Claims] 1. A tube having a rectangular cross section and having different ratios of the short side and the long side thereof, end covers provided at both ends thereof, and a piston slidably fitted in the tube. In the rectangular flat cylinder provided, the piston head of the piston comprises a head body, and a cushioning material fixed to both sides of the head body in the piston movement direction and abutting on the end cover when the piston moves to the tube end. becomes, the rim or the periphery of the cushioning material
Formed so as to extend diagonally to the opposite end cover side
And the inner peripheral surface of the tube
A rectangular flat cylinder having a lip that is deformed inward and slides on an inner peripheral surface thereof . 2. One of the end covers is formed integrally or integrally with the tube, and a pair of supply / discharge holes for supplying / discharging working fluid to / from a cylinder chamber defined by the piston is provided in one end cover. 2. The rectangular flat cylinder according to claim 1, wherein the openings are concentrated.