JPH078660U - Cylinder - Google Patents

Abstract

(57) [Summary] [Purpose] An object of the present invention is to provide a cylinder having a caulking structure with stable caulking strength and excellent workability. [Structure] A bearing housing is provided on one side of a cylinder tube in which a piston is slidably mounted, a step portion is formed at the tip of the bearing housing, and an annular groove is formed inside the step portion, while a cylinder tube is formed. Has a sloping portion at the tip, and an elastic O-ring or other sealing member is interposed between the step portion and the sloping portion, and an external force is applied to the portion of the cylinder tube corresponding to the annular groove to plastically deform it. However, it is characterized in that the caulking portion is immersed in the annular groove.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 This invention relates to a cylinder in which a bearing housing and a cylinder tube are caulked and fixed.

[0002]

[Prior art]

In the conventional cylinder shown in FIGS. 3 and 4, a piston 21 fastened to a piston rod 11 is slidably mounted inside a cylinder tube 10 provided with supply / discharge ports P ₁ and P ₂ . Further, a bearing housing 13 is provided on one side of the cylinder tube 10, and a bearing 20 and a shaft seal member 12 are mounted on the inner periphery of the bearing housing 13 in order from the inner side in the axial direction. The piston rod 11 is passed through the bearing housing 13, and the piston rod 11 is slidably supported by the bearing 20.

An annular groove 14 is formed on the outer periphery of the bearing housing 13 as described above, and a step portion 15 is formed between the annular groove 14 and the tip of the bearing housing 13. Further, a seal groove 16 is formed inside the step portion 15, and a seal member 18 made of an O-ring or the like is attached to the seal groove 16. To mount the bearing housing 13 as described above on the cylinder tube 10, the cylinder tube 10 is inserted until its tip comes into contact with the step portion 15 of the bearing housing 13. After inserting the cylinder tube 10 into the bearing housing 13 in this way, an external force is applied to the portion of the cylinder tube 10 corresponding to the annular groove 14 to plastically deform it, and the caulking portion 17 is immersed in the annular groove 14. Then, the bearing housing 13 is connected to the cylinder tube 10.

Further, in the crimped portion 17 having the above-mentioned configuration, the portions where the upper corners of the annular groove 14 are engaged are referred to as base portions 17a and 17b. As described above, when the bearing housing 13 is attached to the cylinder tube 10, the seal member 18 is crushed, and the seal member 18 is brought into close contact with the cylinder tube 10 and the seal groove 16 by the compression reaction force thereof, and the seal is generated. Exert function. Reference numeral 19 in the figure is an O-ring provided to prevent leakage from the inside of the cylinder to the outside. When pressure oil is supplied to, for example, P ₂ when the cylinder thus configured is in the state of FIG. 3, the piston 21 is moved leftward in the drawing by the action of this pressure oil. When pressure oil is supplied to the supply / discharge port P ₁ with the cylinder extended as described above, the piston 21 moves rightward in the drawing.

[0005]

[Problems to be solved by the device]

 In the conventional cylinder as described above, the caulking portion 17 is caulked by the roller in a state where the cylinder tube 10 is in contact with the step portion 15 of the housing 13, but when the caulking portion 17 is formed in this way, The base portions 17a and 17b and the vicinity thereof are pressed by the corner portions of the annular groove 14 and become thin. When the base portions 17a and 17b become thin in this way, the thinned surplus must be transferred to either one, and the cylinder tube is elongated due to the transfer of the surplus.

However, the extension to the left in the drawing is suppressed by the step portion 15 of the bearing housing 13. Therefore, the extension of the cylinder tube is only rightward in the drawing. For this reason, as the caulking process by the roller progresses, the caulking portion 17 immersed in the annular groove 14 is also subjected to a force to extend rightward in the drawing, and the thickness near the base portion 17b becomes thinner. Therefore, there is a problem that the thickness of the cylinder tube 10 becomes particularly thin in the vicinity of the base portion 17b as compared with other portions, and the caulking strength is not stable.

Therefore, it may be considered that a gap is provided between the step portion 15 of the bearing housing 13 and the tip end surface of the cylinder tube 10 to allow the cylinder tube 10 to extend to the left in the drawing. By doing so, the stretching force generated near the base portion 17a and near the base portion 17b can be equally applied in both directions. However, since the optimum gap between the step portion 15 and the cylinder tube 10 is not uniform under various conditions, there is a problem that its adjustment is extremely difficult. Even if the adjustment could be done, it would have to be adjusted for each individual product, resulting in extremely low work efficiency. If the adjustment is not successful and the gap remains after the caulking process, water will remain in the gap and uneven coating will occur in the subsequent coating process. An object of the present invention is to provide a cylinder that solves the above-mentioned conventional problems even when caulking is performed.

[0008]

[Means for Solving the Problems]

 In order to achieve the above object, the structure of the cylinder according to the present invention comprises a bearing housing on one side of a cylinder tube in which a piston is slidably mounted, and a step is formed at the tip of the bearing housing. While forming an annular groove on the inner side of the step portion, a sloped portion is provided at the tip of the cylinder tube, and an elastic O-ring or other sealing member is interposed between the stepped portion and the sloped portion to form a cylinder. It is characterized in that an external force is applied to a portion of the tube corresponding to the annular groove to plastically deform the portion and the caulked portion is immersed in the annular groove.

[0009]

[Action]

 Since the present invention is configured as described above, when the caulked portion is immersed in the annular groove, the excess thickness of the cylinder tube tends to move to the left and right with the caulked portion as a boundary. At this time, since the seal member is compressed on the side of the gradient portion of the cylinder tube, the extension on the side of the gradient portion is not hindered. Therefore, even the crimped portion of the cylinder tube extends evenly on the left and right. Further, even if a gap is formed between the cylinder tube and the step portion of the bearing housing, the sealing member is interposed between the two, so the expansion rate of the cylinder tube impairs the sealing function of this portion. do not do.

[0010]

【Example】

 In the embodiment according to the present invention shown in FIGS. 1 and 2, a piston (not shown) fixed to a piston rod 11 is slidably mounted inside a cylinder tube 10. Further, a bearing housing 13 is provided on one side of the cylinder tube 10, and a bearing 20 and a shaft seal member 12 are mounted on the inner circumference of the bearing housing 13 in order from the inner side in the axial direction. The piston rod 11 is passed through the bearing housing 13 and the bearing rod 20 slidably supports the piston rod 11. Further, an annular groove 14 is formed on the outer periphery of the bearing housing 13, and a step portion 15 is formed between the annular groove 14 and the tip of the bearing housing 13. On the other hand, the inclined portion 2 is provided inside the tip of the cylinder tube 10.

FIG. 1 shows a state before caulking. To mount the bearing housing 13 on the cylinder tube 10, the seal member 1 made of an elastic O-ring is mounted adjacent to the step portion 15 of the bearing housing 13. However, this seal member 1 need not be an O-ring as long as it has sufficient elasticity and a sealing function. Then, the tip end sloped portion 2 of the cylinder tube 10 is inserted until it comes into contact with the seal member 1 already mounted. Further, an external force is applied to a portion of the cylinder tube 10 corresponding to the annular groove 14 to plastically deform the portion, and the caulked portion 17 is immersed in the annular groove 14 to connect the bearing housing 13 to the cylinder tube 10. There is.

FIG. 2 shows a state after the crimping process. As described above, when the bearing housing 13 is attached to the cylinder tube 10 and caulking is performed, the cylinder tube 10 extends left and right with the caulking portion 17 as a boundary. When the cylinder tube 10 extends in this way, the seal member 1 is crushed on the side of the sloped portion 2. Then, the seal member 1 is brought into close contact with the cylinder tube 10 and the step portion 15 of the bearing housing 13 by the compression reaction force, and exhibits a sealing function. Since the seal member 1 is compressed by the slope portion 2 in this manner, the seal member 1 does not deviate from the gap between the bearing housing 13 and the cylinder tube 10. Therefore, the sealing material portion 1 can prevent the invasion of outside air containing moisture or harmful gas.

[0013]

【effect】

 According to the cylinder of the present invention, the gap between the step portion 15 of the bearing housing 13 and the tip of the cylinder tube 10 is filled with the compressed seal member 1, so that moisture and the like will not be retained therein. As a matter of course, rust and other erosion can be prevented. Also, even in the painting process, uniform painting can be performed. Further, since the gap is filled with the compressed seal member 1 as described above, even if there is some error in the elongation rate of the cylinder tube during the crimping process, the sealing property is not affected. Therefore, it is not necessary to predict the elongation rate and accurately determine the length of the cylinder tube. Furthermore, since the caulking portion 17 extends evenly to the left and right, only one base portion as in the conventional case does not become thin. Therefore, there is no difference in thickness between the base portions 17a and 17b, and the caulking strength can be stabilized.

[Brief description of drawings]

FIG. 1 is an enlarged sectional view of an essential part showing an embodiment of the present invention.

FIG. 2 is an enlarged sectional view of an essential part showing an embodiment of the present invention.

FIG. 3 is a sectional view showing a conventional example of the present invention.

FIG. 4 is an enlarged cross-sectional view of a main part of FIG.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Seal member 2 Gradient part 10 Cylinder tube 13 Bearing housing 14 Annular groove 15 Step part 21 Piston

Claims (1)

[Scope of utility model registration request] 1. A bearing housing is provided on one side of a cylinder tube in which a piston is slidably mounted, a step portion is formed at the tip of the bearing housing, and an annular groove is formed inside the step portion. A sloped portion is provided at the tip of the cylinder tube, and an elastic O-ring or other sealing member is interposed between the stepped portion and the tip of the cylinder tube, and an external force is applied to the portion of the cylinder tube corresponding to the annular groove to make it plastic. A cylinder that has been deformed and has the caulked part immersed in the annular groove.