JPH09303320A - Hydraulic cylinder - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a hydraulic cylinder which is small in the number of part items and easy in assembly work. SOLUTION: Ports 10, 11 are provided in cylinder covers 5, 6, and a piston 3 is stored in a piston storage hole 4 to demarcate pressure actuation chambers S1, S2. A fluid transfer hole 9 to introduce the fluid to be fed to the port 11 to the pressure actuation chamber S1 on the cover 5 side is formed in a tube 2. Gaskets 17, 18 as sealing members to seal an opening part of the piston storage hole 4 are interposed between the tube 2 and the covers 5, 6. A projected piece 20 extended to the side of the gasket body 19 in the gaskets 17, 18 is interposed between the tube 2 and the covers 5, 6 so as to seal the opening part of the fluid transfer hole 9. A fluid passage to communicate the pressure actuation chamber S1 on the cover 5 side with the fluid transfer hole 9 is arranged on the cover 5.

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 having a centralized piping structure.

[0002]

2. Description of the Related Art Conventionally, a cylinder utilizing the pressure of a fluid such as air has been known. With this kind of cylinder,
In recent years, there has been a case where ports for supplying air into the cylinder tube are intensively arranged on one of the cylinder covers. An example of a conventional cylinder having such a centralized piping structure is shown in FIGS. 8 and 9.

A substantially oval-shaped piston accommodating hole 64 for accommodating the piston 63 in a reciprocating manner is provided at the center of a rectangular cylinder tube 62 which constitutes the fluid pressure cylinder 61 of FIG. There is. Both ends of the tube 62 are closed by a rod cover 65 and a head cover 66. The piston 63 divides the inside of the tube 62 into two pressure action chambers S1 and S2. The head cover 66 is provided with two fluid supply ports 67 and 68. The first port 67 of the ports 67 and 68 is the fluid flow path 6 provided in the head cover 66.
It communicates with the head side pressure action chamber S2 via 9.
The second port 68, which is the other side, includes a fluid passage 70 provided in the head cover, a fluid transfer hole 71 provided at a corner of the tube 62, and a fluid passage 72 provided at the rod cover 65. Through the rod side pressure action chamber S1
Is communicated to.

In the cylinder 61, between the tube 62 and the covers 65 and 66, a substantially elliptical gasket 73 as a seal member for sealing the opening of the piston receiving hole 64 is interposed. In addition, an O-ring 74 as a sealing member that seals the opening of the fluid transfer hole 71 is interposed between the tube 62 and the covers 65 and 66. Therefore, the first port 67 of this cylinder 61
When the fluid is supplied to the side, the piston 63 moves to the rod side end, and the rod 75 projects. Also,
When the fluid is supplied to the second port 68 side, the fluid is guided to the rod side pressure action chamber S1 through the fluid flow passages 70 and 72 and the fluid transfer hole 71. Then, the piston 63 moves to the end on the head side, so that the rod 75 is retracted.

[0005]

However, in the conventional fluid pressure cylinder 61, the tube 62, the cover 65,
It is necessary to separately assemble the seal member 73 and the O-ring 74 at the interface with 66, and there is a problem that the assembly work is complicated. Moreover, since the O-ring 74 is small, it may be lost during assembly. Therefore, in this type of cylinder 61, it has been required to reduce the number of parts as much as possible.

Further, since the conventional cylinder 61 requires a complicated process for forming the communication hole 72 in the rod cover 65, there is a demand for a cylinder structure that does not require such a hole process.

The present invention has been made in view of the above circumstances, and an object thereof is to provide a fluid pressure cylinder having a small number of parts and easy to assemble. Also,
Another object of the present invention is to provide a fluid pressure cylinder that does not require drilling in the cylinder cover.

[0008]

In order to solve the above-mentioned problems, in the invention described in claim 1, a fluid supply port is provided in one of two cylinder covers for closing both ends of the cylinder tube, A pressure transfer chamber is defined in the tube by accommodating the piston in the piston reception hole of the tube, and a fluid transfer hole is formed in the tube to guide the fluid supplied to the port to the pressure operation chamber on the other cover side. And in a fluid pressure cylinder in which a seal member for sealing the opening of the piston housing hole is interposed between the tube and the cover, a protrusion extending laterally of the seal member main body, Intervening between the tube and the cover to seal the opening of the fluid transfer hole,
Also, a fluid pressure passage is provided in at least one of the cover, the seal member, and the tube, and a fluid flow path for communicating the pressure acting chamber on the other cover side with the fluid transfer hole is provided. The summary will be given.

According to a second aspect of the present invention, in the first aspect, the projecting piece has a through hole penetrating the front and back sides thereof. According to a third aspect of the present invention, in the first or second aspect, a communication groove extending from the protruding piece to the seal member main body is formed.

According to a fourth aspect of the present invention, in the third aspect, the edges of the communication groove and the periphery of the through hole are surrounded by a ridge. According to a fifth aspect of the present invention, in any one of the first to fourth aspects, the surface of the seal member main body that faces the tube has a shape corresponding to the shape of the opening of the piston housing hole. It is assumed that the fitting protrusion is formed.

Hereinafter, the "action" of the present invention will be described. According to the invention described in claims 1 to 5, the fluid supplied to the port on one cylinder cover side flows through the fluid transfer hole formed in the tube and the fluid flow path arranged in the cover, the seal member, or the like. Through the pressure acting chamber on the other side. At that time, the opening of the fluid transfer hole is sealed by the projecting piece extending to the seal member body, and fluid leakage from the opening is prevented. Since the projecting piece is a part of the seal member and plays a role equivalent to that of the conventional O-ring, as a result, the number of parts is reduced. Therefore, the assembling work becomes easier as compared with the conventional case in which the seal member and the O-ring are separate.

According to the second aspect of the invention, the fluid can be circulated to the opposite side surface of the seal member through the through hole, and at that time, the opening of the fluid transfer hole can be sealed. .

According to the third aspect of the invention, the fluid can be moved along the communication groove extending from the projecting piece to the seal member body, so that the fluid can flow between the fluid transfer hole side and the pressure action chamber side. You can Further, with this configuration, it is not necessary to machine holes on the cylinder cover side.

According to the fourth aspect of the present invention, when the edge of the communication groove and the periphery of the through hole are surrounded by the protrusions, it becomes difficult to form a gap between the seal member and the cover or the tube. The sealing property is improved.

According to the invention of claim 5, the seal member is easily positioned with respect to the tube by fitting the fitting convex portion into the piston accommodating hole. Further, the positional displacement of the seal member after being once positioned is prevented.

[0016]

BEST MODE FOR CARRYING OUT THE INVENTION [Embodiment 1] Hereinafter, a first embodiment of the present invention will be described in detail with reference to FIGS.

The cylinder tube 2 constituting the fluid pressure cylinder 1 is a metal extruded material and has a rectangular shape. A substantially elliptical piston accommodating hole 4 for accommodating the piston 3, which is a moving body, in a reciprocating manner is transparently provided at the center of the cylinder tube 2. The upper end surface of the tube 2 is closed by a metal rod cover 5.
On the other hand, the lower end surface of the tube 2 is closed by a head cover 6 which is also made of metal. It should be noted that bolt insertion holes 8 for inserting the bolts 7 for fixing the covers 5 and 6 are transparently provided at two locations in the corner portion of the cylinder tube 2. Fluid transfer holes 9 through which air as a fluid can flow are provided at the remaining two places in the corner portion. Since the bolt insertion hole 8 and the fluid transfer hole 9 extend along the longitudinal direction of the tube 2, they can be formed at the same time when the tube 2 is extruded. Further, the piston 3 accommodated in the piston accommodating hole 4 divides the space inside the tube 2 into two, that is, the rod side pressure action chamber S1 and the head side pressure action chamber S2.

On the outer end surface of the head cover 6, two fluid supply ports 10 and 11 are provided. In the head cover 6, two in-cover fluid flow passages 12 and 13 penetrating the inner and outer end surfaces thereof are formed by hole processing using a drill or the like. The in-cover fluid flow path 12 having the first port 10 as a base end is short and linear, and opens at a position corresponding to the head side pressure action chamber S2. Second port 1
The in-cover fluid flow path 13 having a base end 1 is bent and opens at the outer peripheral portion of the head cover 6. Therefore, the in-cover fluid flow path 13 is terminated not at the position corresponding to the head side pressure action chamber S2 but at the position corresponding to the fluid transfer hole 9.

The piston 3 is provided at the center of the rod cover 5.
A rod insertion hole 15 for inserting the rod 14 fixed to is formed. Further, an in-cover fluid flow path 16 is formed in the rod cover 5 by bending in a substantially U-shape. The in-cover fluid passage 16 does not open on the outer end face side of the rod cover 5, but opens on two places on the inner end face side. That is, the base end is at a position corresponding to the fluid transfer hole 9, and the end is at the rod side pressure action chamber S1.
It is in a position corresponding to.

Recesses 5a and 6a for accommodating gaskets 17 and 18 as seal members are formed on the inner end surface of the rod cover 5 and the inner end surface of the head cover 6, respectively. Hereinafter, the configuration of the gaskets 17 and 18 interposed between the tube 2 and the covers 5 and 6 will be described.

As shown in FIG. 1, the gaskets 17 and 18 of the present embodiment include a substantially elliptical gasket body 19 and two projecting pieces extending laterally at both ends of the gasket body 19. And 20. In the present embodiment, the gaskets 17 and 18 are molded products manufactured by integral molding using urethane rubber as a material. Therefore, the gaskets 17 and 18 have elasticity suitable as a seal member. Through holes 21 having a circular cross section are formed at both ends of the gasket body 19 so as to penetrate the front and back of the gasket body 19. Each projecting piece 20 also has a through hole 22 having a circular cross section that penetrates the front and back sides of the projecting piece 20. These through holes 21 and 22 correspond to the positions of the in-cover fluid flow paths 12, 13 and 16 and the openings of the fluid transfer holes 9. A rod insertion hole 23 is formed in the center of the gasket body 19 of the rod-side gasket 17 among these gaskets 17, 18. On the other hand, the head side gasket 18 does not have such a structure.

A fitting convex portion 24 having a shape corresponding to the shape of the opening of the piston accommodating hole 4 is formed on the surface of the gasket body 19 on the tube 2 side (that is, the inner end surface). Therefore, when the gaskets 17 and 18 are interposed between the tube 2 and the covers 5 and 6, the fitting protrusion 24 fits into the piston housing hole 4. At this time, the projecting piece 20 is designed to be located exactly at the opening of the fluid transfer hole 9.

Now, the operation of the cylinder 1 will be briefly described. A pressure supply source and an electromagnetic switching valve (not shown) are provided outside the cylinder 1, and air is supplied to and discharged from both ports 10 and 11 via them. When air is supplied to the first port 10 side, the air is supplied to the in-cover fluid passage 12 and the head-side gasket 18
Through the through hole 21 and flows into the head side pressure action chamber S2. At this time, the air in the rod-side pressure action chamber S1 passes through the through hole 21, the in-cover fluid flow path 16, the through hole 22, the fluid transfer hole 9, the through hole 22 and the in-cover fluid flow path 13, and Reach port 2 of 2. Then, the air is finally discharged to the outside of the cylinder 1. Therefore, at this time, the piston 3 moves to the rod side end, and as a result, the rod 14 projects from the cylinder tube 2.

On the contrary, when air is supplied to the side of the second port 11, the air is supplied to the fluid channel 13 in the cover and the through hole 2.
2, fluid transfer hole 9, through hole 22, in-cover fluid flow path 1
6. After passing through the through hole 21, it flows into the rod side pressure action chamber S1. At this time, the air in the head side pressure action chamber S2 passes through the through hole 21 and the in-cover fluid flow passage 12 and reaches the first port 10. Then, the air is finally discharged to the outside of the cylinder 1. Therefore, at this time, the piston 3 moves to the end on the head side, and as a result, the rod 14 sinks into the cylinder tube 2.

The characteristic effects of this embodiment will be listed below. (A) According to the cylinder 1, the opening of the fluid transfer hole 9 is sealed by the protrusion 20 extending from the gasket body 19. Therefore, even when air is introduced into the rod side pressure action chamber S1 through the fluid transfer hole 9 or the like, air does not leak from the opening of the fluid transfer hole 9.
The protrusion 20 is a part of the gaskets 17 and 18,
In addition, it plays a role equivalent to that of a conventional O-ring.
Therefore, the O-ring can be omitted, and as a result, the number of parts can be reduced. Therefore, the assembling work is easier than in the conventional case where the gasket and the O-ring are separate.

(B) In this cylinder 1, the air can be guided to the opposite side surface of the gasket 17 through the through hole 22 of the projecting piece 20, and further the air can be communicated with the cover side fluid passage 16. Then, at that time, the opening of the fluid transfer hole 9 is sealed, and air leakage from the portion can be prevented.

(C) In this cylinder 1, the gasket 1
Fitting protrusions 24 that fit into the piston housing holes 4 are provided on the inner end surfaces of the members 7 and 18. Therefore, the gaskets 17, 18
Can be easily positioned with respect to the tube 2,
Moreover, it is possible to prevent the gaskets 17 and 18 from being displaced once they have been positioned. [Second Embodiment] A second embodiment of the present invention will be described in detail below with reference to FIGS. It should be noted that parts having the same configurations as those in the first embodiment are given the same reference numerals, and detailed description thereof will be omitted.

In the fluid pressure cylinder 31 of this embodiment, the rod cover 5 has a rod side pressure chamber S1.
The cover-side fluid flow passage 16 is not formed as a fluid flow passage for communicating the fluid transfer hole 9 with the fluid transfer hole 9. Instead, a communication groove 33 serving as such a fluid flow path is formed in a notch on the upper end surface of the cylinder tube 2. Therefore, in this embodiment, the gasket 32 having no through holes 21 and 22 is arranged on the rod side.

The characteristic effects of this embodiment will be listed below. (A) The effects of a and c described in the first embodiment are achieved. (B) With this cylinder 31, the air can move along the communication groove 33 provided in the tube 2, so the cover-side fluid passage 16 is not essential. Further, the processing for forming the notch in the groove is not as difficult as the hole processing. As described above, since the hole processing of the rod cover 5 is unnecessary, the manufacturing cost of the cylinder 1 can be reduced. With this structure, the gasket 3 on the cover side
The configuration of 2 also needs to be simple. [Third Embodiment] Hereinafter, a third embodiment of the present invention will be described in detail with reference to FIGS. It should be noted that parts having the same configurations as those of the above-described embodiment are given only the same member numbers, and detailed description thereof will be omitted.

As shown in FIG. 5, in the rod cover 5 of the fluid pressure cylinder 41, the fluid flow path that connects the rod side pressure action chamber S 1 and the fluid transfer hole 9 is defined by the rod cover 5 and the cylinder tube 2. Is not formed on either side of. Instead, a structure serving as such a fluid flow path is formed on the gasket 42 side. That is, in the gasket 42, the communication groove 43 extending from the through hole 22 of the projecting piece 20 to the through hole 21 of the gasket body 19 is formed. The communication groove 43 is bent in a substantially V shape and exists on the outer end face side of the gasket 42. Therefore, the air in the fluid transfer hole 9 passes through the through hole 22, the communication groove 43 and the through hole 21 and is introduced into the rod side pressure action chamber S1.

The characteristic effects of this embodiment will be listed below. (A) The effects of a and c described in the first embodiment are achieved. (B) With this cylinder 41, the air can move along the communication groove 43 provided in the gasket 42, so that the cover-side fluid flow path 16 is not essential. As described above, since the hole processing of the rod cover 5 is unnecessary, the manufacturing cost of the cylinder 1 can be reduced.

(C) FIG. 6A shows a modified gasket 42A. The gasket body 19 of the gasket 42A has three through holes 21 formed therethrough.
Further, in FIG. 6A, the inner end side of the communication groove 43 on the right side is in a non-penetrating state. Gasket 42A having the above configuration
Then, as shown in FIGS. 6 (b) and 6 (c),
It can be used on both the rod end face side and the head end face side. Therefore, commonality of parts can be achieved.

The present invention can be modified as follows, for example. (1) In the gasket 51 of another example shown in FIG. 7, the edges of the communication groove 43 and the peripheries of the through holes 21 and 22 are surrounded by the protrusions 52. Therefore, the adhesion force at the edge of the communication groove 43 is increased, and it becomes difficult to form a gap between the outer end surface of the gasket 51 and the inner end surfaces of the covers 5 and 6. Therefore, the sealability between the gasket 51 and the covers 5 and 6 can be improved.

(2) The communication groove 43 formed in the gaskets 42 and 51 may not be on the outer end face side, but may be on the inner end face side. Instead of the communication groove 43, the gaskets 42, 5
The holes may be provided along the lateral direction of 1.

(3) The material of the gaskets 17, 18 ... Is not limited to urethane, but other resin materials,
For example, fluororubber or NBR may be used. In this case, it is desirable to select a material having elasticity such as urethane rubber in order to secure the sealing property.

(4) The fitting recesses 24 of the gaskets 17, 18, ... Are not essential and can be omitted. Even if such a fitting recess 24 is not formed, the positioning of the protrusion 20 allows the positioning to some extent.

(5) The fluid supply ports 10 and 11 may be formed on the head cover 6 side as in the embodiment, or may be formed on the rod cover 5 side. (6) A fluid flow path that connects the pressure action chamber S1 on the rod cover 5 side and the fluid transfer hole 9 is provided in both the cover 5 and the gasket 17, both the cover 5 and the tube 2, or both the gasket 17 and the tube 2. It may be arranged at.

(7) The number of the protrusions 20 on the gaskets 17, 18 ... Is the same as the number of the fluid transfer holes 9 formed on the tube 2 side.
It can be increased or decreased according to the number of. Therefore, it is also permissible to use only one protrusion 20 or three or more protrusions 20.

Here, in addition to the technical ideas described in the claims, the technical ideas grasped by the above-described embodiments will be listed below together with their effects. (1) A gasket interposed between a cylinder tube of a fluid pressure cylinder and a cylinder cover, the gasket for fluid pressure cylinder comprising a gasket main body and a protrusion extending from the side thereof. By using the gasket having this structure, the fluid pressure cylinder of the present invention can be reliably implemented.

(2) In the technical idea 1, the projection piece is a gasket for a fluid pressure cylinder having through holes penetrating the front and back sides thereof. If you use the gasket of this configuration,
The fluid pressure cylinder of the present invention can be reliably implemented, and
Manufacturing costs can be reduced.

(3) In the technical ideas 1 and 2, a gasket for a fluid pressure cylinder having a communication groove extending from the protruding piece to the seal member body. By using the gasket having this structure, the fluid pressure cylinder of the present invention can be reliably implemented and the manufacturing cost can be reduced.

(4) In the technical idea 3, a gasket for a fluid pressure cylinder in which an edge portion of the communication groove and the periphery of the through hole are surrounded by a protrusion. By using the gasket having this structure, the fluid pressure cylinder of the present invention can be reliably implemented and the sealing performance can be improved.

The technical terms used in this specification are defined as follows. "Fluids: nitrogen, oxygen, argon, carbon dioxide, hydrogen,
In addition to the various gases represented by the mixture such as air, liquids such as oil and water are also included. "

[0044]

As described in detail above, according to the invention described in claims 1 to 5, it is possible to provide a fluid pressure cylinder having a small number of parts and easy to assemble.

According to the second and third aspects of the present invention, it is not necessary to form holes on the cylinder cover side, so that the manufacturing cost can be reduced. According to the invention described in claim 4, the sealability between the cover and the tube can be further improved.

According to the fifth aspect of the present invention, the positioning work of the seal member can be facilitated and the displacement thereof can be prevented.

[Brief description of drawings]

FIG. 1 is an exploded perspective view showing a fluid pressure cylinder according to a first embodiment.

FIG. 2 is a sectional view of the cylinder.

FIG. 3 is an exploded perspective view showing a fluid pressure cylinder according to a second embodiment.

FIG. 4 is a sectional view of the cylinder.

FIG. 5 is an exploded perspective view showing a fluid pressure cylinder according to a third embodiment.

FIG. 6 (a) is a partial perspective view of a modified gasket of the cylinder, and FIGS. 6 (b) and 6 (c) are partial cross-sectional views of the assembled gasket taken along its communication groove.

FIG. 7 is a partially enlarged sectional view of a seal member of a fluid pressure cylinder of another example.

FIG. 8 is an exploded perspective view showing a conventional fluid pressure cylinder.

FIG. 9 is a sectional view showing a conventional fluid pressure cylinder.

[Explanation of symbols]

1, 31, 41 ... Fluid pressure cylinder, 2 ... Cylinder tube, 3 ... Piston, 4 ... Piston accommodating hole, 5 ... Rod cover as cylinder cover, 6 ... Head cover as cylinder cover, 9 ... Fluid transfer hole, 10, 11 ... Fluid supply port, 17, 18, 32, 42, 42A, 51
... gasket as seal member, 19 ... gasket body as seal member main body, 20 ... projecting piece, 22 ... through hole, 24 ... fitting convex portion, 33 ... communication groove as fluid passage,
43 ... Communication groove as fluid flow path, 52 ... Projection line, S1, S
2… Pressure action chamber.

Claims (5)

[Claims] 1. A pressure action chamber is defined in a tube by providing a fluid supply port in one of two cylinder covers for closing both ends of the cylinder tube and accommodating a piston in a piston accommodating hole of the tube. A fluid transfer hole for guiding the fluid supplied to the port to the pressure action chamber on the other cover side is formed in the tube, and a seal member for sealing the opening of the piston accommodating hole is provided between the tube and the cover. In a fluid pressure cylinder interposed between the tube and the cover, a protrusion extending laterally of the seal member body is interposed between the tube and the cover to seal the opening of the communication hole, Also, a fluid flow path that connects the pressure acting chamber on the other cover side and the fluid transfer hole is provided in at least one of the cover, the seal member, and the tube. A fluid pressure cylinder characterized in that 2. The fluid pressure cylinder according to claim 1, wherein the projecting piece has a through hole that penetrates the front and back sides of the projecting piece. 3. The fluid pressure cylinder according to claim 1, wherein a communication groove extending from the projecting piece to the seal member main body is formed. 4. The fluid pressure cylinder according to claim 3, wherein an edge of the communication groove and the periphery of the through hole are surrounded by a ridge. 5. The fitting convex portion having a shape corresponding to the shape of the opening of the piston accommodating hole is formed on the surface of the seal member body on the tube side. The fluid pressure cylinder according to any one of 1 to 4.