JPH09133109A - Hydraulic cylinder - Google Patents

Abstract

PROBLEM TO BE SOLVED: To supply and discharge operating fluid for a piston room of a head side and a piston room of a rod side by either a rod piece or a head piece and to supply and discharge a large quantity of operating fluid without enlarging a cylinder tube. SOLUTION: Through holes 4A to 4D are formed at corners 2A to 2D of a cylinder tube 2 which is formed in a rectangular cross section. A rod cover 5 and a head cover 15 are fixed to the cylinder tube 2 by fixing screws 8, 18 which are screwed in female threads maded in both ends of the through holes 4A, 4B. Passages 13, 14 for communicating with the through hole 4D and a piston room of a rod side are formed in the rod cover 5. A passage 20 for communicating with the through hole 4D and a port 21 of a rod side is formed in the head cover 15. And a passage 22 for communicating with a port 23 of a head side and the piston room of the head side is formed in the head cover 15.

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.

[0002]

2. Description of the Related Art In fluid pressure cylinders such as air cylinders,
The piston is driven bidirectionally by alternately supplying and discharging the working fluid to and from the head side piston chamber and the rod side piston chamber in the cylinder tube. The working fluid is supplied to and exhausted from the head-side piston chamber via a supply / exhaust port provided in the head piece, and the working fluid is supplied to / exhausted from the rod-side piston chamber via a supply / exhaust port provided in the rod piece. . Each supply / exhaust port is connected to a conduit from a directional control valve that supplies / exhausts a working fluid supplied from a pressure source.

By the way, when the pipe lines from the directional control valve are connected to the respective supply / exhaust ports of the head piece and the rod piece, the pipe lines are arranged around the cylinder tube. As a result, when it is desired to centrally install a large number of fluid pressure cylinders in a manufacturing process in which the fluid pressure cylinders are used, the pipe lines connected to the respective fluid pressure cylinders obstruct the installation. In addition, when the user performs maintenance on each fluid pressure cylinder, the pipeline becomes an obstacle and maintenance work becomes difficult.

Therefore, in order to solve such a problem,
In the actuator of Japanese Patent Publication No. 7-51962, as shown in FIGS. 12 and 13, a transfer passage 51 is formed so as to circulate a working fluid in the central axis direction of the cylinder tube 50, and the transfer passage 51 is covered with a rod cover. It communicates with the rod side piston chamber 54 via a flow path 53 provided in 52. On the other hand, the head side of the transfer channel 51 is communicated with the rod side channel 56 provided in the head cover 55. Further, the head cover 55 is provided with a head side flow passage 58 communicating with the head side piston chamber 57. Therefore, the head cover 55 is provided with the rod-side flow passage 56 that communicates with the rod-side piston chamber 54 and the head-side flow passage 58 that communicates with the head-side piston chamber 57, so that a pipe passage is formed around the cylinder tube 50. There is no need to provide it.

In this actuator, a female screw hole 5 for attaching the rod cover 52 or the head cover 55 to each corner 50a of the cylinder tube 50 having a rectangular cross section is provided.
9 are provided. Therefore, the transfer channel 51 is formed between the female screw holes 59 of the cylinder tube 55.

[0006]

By the way, in order to operate the fluid pressure cylinder at a high speed, it is necessary to increase the amount of the working fluid supplied / exhausted per hour. Need to be bigger.

However, in the above actuator,
Cylinder tube 5 between transfer channel 51 and both corners 50a
Since the thickness of 0 is provided at a portion where the wall thickness is thin, it is necessary to increase the wall thickness of the cylinder tube 50 in order to obtain a large flow passage cross-sectional area. As a result, the cylinder tube 5
0 becomes large and heavy.

The present invention has been made in order to solve the above problems, and its object is to supply or exhaust the working fluid to or from the head-side piston chamber and the rod-side piston chamber by one of the head piece and the rod piece. It is an object of the present invention to provide a fluid pressure cylinder which can be carried out in accordance with (1) and can obtain a large supply / discharge amount of working fluid without increasing the size of the cylinder tube.

[0009]

In order to solve the above problems, the invention according to claim 1 is formed into a substantially square shape,
In a fluid pressure cylinder having cylinder tubes each having a through hole for fixing a rod piece or a head piece at each corner thereof, at least any one of the through holes is defined as a rod piece. A transfer passage for supplying and exhausting the working fluid is provided between the head side piston chamber or between the head piece and the rod side piston chamber.

According to a second aspect of the present invention, in the first aspect of the invention, the direction switching for switching the working fluid to the rod-side piston chamber or the head-side piston chamber via the transfer passage and exhausting the working fluid is performed. The valve was integrated into either the headpiece or the rodpiece.

According to a third aspect of the invention, in the invention according to the first or second aspect, the cylinder tube is formed by metal extrusion molding, and each through hole is formed during extrusion molding. did.

Therefore, according to the first aspect of the present invention,
Between the rod piece and the head side piston chamber, a through hole for attaching the rod piece or the head piece to the cylinder tube is provided as a transfer passage, which is provided in a corner portion of the cylinder tube formed in a substantially rectangular shape. Alternatively, the working fluid is supplied and exhausted between the head piece and the rod-side piston chamber. Since the piston is formed in a substantially circular shape, the wall thickness of each corner of the substantially rectangular cylinder tube is formed to be thicker than the wall thickness between adjacent corners. Therefore, by using the through-holes formed in the corners as the transfer flow passages, it is possible to obtain a large flow passage cross-sectional area without increasing the cross-sectional area of the cylinder tube.

According to the second aspect of the present invention, the first aspect is provided.
In addition to the operation of the invention described in (1), since the directional switching valve is integrally provided in the rod piece or the head piece in which the rod side piston chamber and the head side piston chamber are both communicated by the transfer flow path, The port communicates with each piston chamber through a flow path provided inside the rod piece or the head piece. As a result, it is possible to integrate the directional control valve and the fluid pressure cylinder without providing a pipe line communicating between the directional control valve and the rod piece or the head piece outside the fluid pressure cylinder.

According to the invention described in claim 3, according to claim 1 of the present invention,
Alternatively, in addition to the effect of the invention described in claim 2, the through holes are simultaneously formed during extrusion molding of the cylinder tube.

[0015]

BEST MODE FOR CARRYING OUT THE INVENTION

[First Embodiment] A first embodiment in which the present invention is embodied in an air cylinder will be described below with reference to FIGS. 1 and 2.

As shown in FIG. 1, an air cylinder 1 is provided with a cylinder tube 2 having a quadrangular cross section, and a piston hole 3 having an oval cross section is formed at the center of the cylinder tube 2. Has been done. Cylinder tube 2
Through holes 4A, 4B, 4 penetrating the cylinder tube 2 in the direction of the central axis in each of the corners 2A, 2B, 2C, 2D.
C and 4D are formed respectively. The cylinder tube 2 is formed by extrusion molding, and the through holes 4A, 4B, 4C, 4D are simultaneously formed during extrusion molding. Female thread portions (not shown) are formed by secondary processing at both ends of the through holes 4A and 4C.

A rod cover 5 is fixed to the rod side of the cylinder tube 2. Threaded holes 6 and 7 are formed at respective positions facing the through holes 4A and 4C of the rod cover 5, respectively. The screw holes 6 and 7 are screwed into female screw portions to mount the rod cover 5 on the cylinder. A fixing screw 8 for fixing the tube 2 is inserted.

A rod hole 9 is formed in the central portion of the rod cover 5, and the proximal end side of the piston rod 10 is introduced into the piston hole 3 through the rod hole 9. A piston 11, which is slidably formed in the piston hole 3, is fixed to the base end of the piston rod 10. FIG. 2 (a),
As shown in (b), the rod side piston chamber 12 is formed in the piston hole 3 by the piston 11 and the rod cover 5.
Are formed. A flow path 13 communicating with the through hole 4D is formed at a position of the rod cover 5 facing the through hole 4D, and a flow path 14 communicating between the flow path 13 and the rod side piston chamber 12 is formed. Are formed.

On the head side of the cylinder tube 2,
The head cover 15 is fixed. Through holes 4A, 4C
Screw holes 16 and 17 are formed at positions of the head cover 15 facing each other.
A fixing screw 18 which is screwed into a female screw portion and fixes the head cover 15 to the cylinder tube 2 is inserted into the screw 17. A head side piston chamber 19 is formed in the piston hole 3 by the head cover 15 and the piston 11.

A head cover 15 facing the through hole 4D.
A flow path 20 is formed at the position of, and the flow path 20 is communicated with a rod side port 21 also provided in the head cover 15. Therefore, in the present embodiment, the through hole 4D
At, a transfer flow path that connects the rod-side piston chamber 12 to the rod-side port 21 provided in the head cover 15 is formed.

A flow path 22 is formed at a position of the head cover 15 facing the head side piston chamber 19, and the flow path 22 is communicated with a head side port 23 also provided in the head cover 15. Each of the ports 21 and 23 is equipped with a joint 24 to which a conduit from an external directional switching valve (not shown) is connected.

Next, the operation of the fluid pressure cylinder constructed as described above will be described. In the state shown in FIG. 2B, when the direction switching valve operates so that air is supplied to the head side port 23 and air is discharged from the rod side port 21, the head side piston chamber 19 is supplied to the head side piston chamber 19 via the flow path 22. The air is supplied, and the air is exhausted from the rod-side piston chamber 12 through the flow paths 13 and 14 and the through hole 4D. As a result, the piston 11 is driven from the head side to the rod side.

At this time, since the through hole 4D is formed in the corner portion 2C of the rectangular cylinder tube 2, the flow passage cross-sectional area is large. Therefore, since the amount of supply / exhaust air per time is large, the piston 11 is driven at high speed.

On the contrary, when air is supplied to the rod side port 21 and air is exhausted from the head side port 23, air is supplied to the rod side piston chamber 12 through the through hole 4D and the flow paths 13 and 14. At the same time, air is exhausted from the rod-side piston chamber 19 via the flow path 22. As a result, the piston 11 is driven at high speed from the rod side to the head side.

As described in detail above, according to the air cylinder of this embodiment, the following effects can be obtained. (A) Through holes 4A to 4D provided in respective corners 2A to 2D of the cylinder tube 2 having a rectangular cross section.
Among these, the through hole 4D that is not used for screwing the rod cover 5 and the head cover 15 into the cylinder tube 2 is used as a transfer flow path, and the rod side piston chamber 12 is connected to the head piece 15 via the transfer flow path. It communicated with the provided rod side port 21. As a result, the cylinder tube 2
Since the transfer channel can be provided in the thick corner 2D, the channel having a large channel cross-sectional area can be obtained without increasing the sectional area of the cylinder tube 2. Therefore, the air cylinder 1 that drives the piston 11 at high speed can be achieved without increasing the size of the cylinder tube 2, that is, the air cylinder 1 in order to increase the flow passage cross-sectional area of the transfer flow passage.

(B) Each corner 2A of the cylinder tube 2
Since the through hole 4D of the corner 2D is used as the transfer flow path while the thickness of the portion between 2D and 2D is reduced, the cylinder tube 2 has no excess thickness. As a result, waste of material cost can be eliminated.

Further, the cylinder tube 2 has a through hole 4A.
In addition to 4D, no extra through-holes are provided, so that the cross-sectional shape can be line-symmetric with respect to the axis of symmetry that intersects at right angles. As a result, when the cylinder tube 2 is formed by extrusion molding, the balance of molding is not lost, so that the cylinder tube 2 with high accuracy can be obtained. (C) Form the cylinder tube 2 by extrusion molding,
The through holes 4A to 4D were simultaneously formed at the time of extrusion molding. Therefore, the processing cost of the cylinder tube 2 can be reduced as compared with the construction method in which the through holes 4A to 4D are punched by the secondary processing after extrusion molding.

[Second Embodiment] Next, a second embodiment of the present invention will be described with reference to FIG. still,
The present embodiment differs from the first embodiment only in that the head cover 15 is replaced with a head cover 30 in the first embodiment. Therefore, the head cover 3
Only 0 will be described in detail, and the same components as those in the first embodiment will be denoted by the same reference numerals and the description thereof will be omitted.

As shown in FIGS. 3A and 3B, a known 2-position 5-port directional switching solenoid valve (hereinafter referred to as directional switching valve) 31 is disposed inside the head cover 30. The directional control valve 31 includes a first input / output port, a second input / output port, an air supply port, a first exhaust port, and a second exhaust port, which are not shown. Head cover 3
In 0, a flow passage 32 that communicates the through hole 4D and the first input / output port, a flow passage 33 that communicates the head side piston chamber 19 and the second port, and an air supply port 34 provided in the head cover 30. A flow path 35 that connects the air supply port and the air supply port is formed. In addition, a flow path (not shown) that connects the first silencer 36 and the first exhaust port provided in the head cover 30 and a flow path (not shown) that also connects the second silencer 37 and the second exhaust port are provided. Each is formed.

The direction switching valve 31 is switched between the first position and the second position. In the first position, the direction switching valve 31 introduces the air supplied from the air supply port 34 from the air supply port, and the rod side piston chamber 12 from the first input / output port via the flow path 32 and the through hole 4D. Air from the head side piston chamber 19 is introduced into the second input / output port through the flow path 33, and the air is supplied to the first exhaust port from the exhaust port.
It is led to the outside air via the muffler 36. Further, in the second position, the direction switching valve 31 introduces the air supplied from the air supply port from the air supply port and supplies the air from the second input / output port to the head side piston chamber 19 via the flow path 33. At the same time, the air in the rod side piston chamber 12 is passed through the through hole 4
Introduced to the first input / output port via D and the flow path 32,
It is led to the outside air from the exhaust port via the second silencer 37.

Next, the operation of the air cylinder configured as described above will be described. The direction switching valve 31 supplies air to the rod side piston chamber 12, and the head side piston chamber 1
When air is exhausted from 9, the piston 11 is driven from the rod side to the head side. On the contrary, when the direction switching valve 31 supplies air to the head side piston chamber 12 and exhausts air from the rod side piston chamber 19, the piston 11 is driven from the head side to the rod side.

According to the air cylinder of the present embodiment, the following effects can be obtained in addition to the effects of the air cylinder of the first embodiment. (A) The directional switching valve 31 is incorporated in the head cover 30 in which the rod-side piston chamber 12 communicates with the through-hole 4D and the head-side piston chamber 19 communicates therewith.
Further, the respective ports of the directional control valve 31 and the respective piston chambers 12 and 19 are communicated with each other through the flow paths 32 and 33 provided in the head cover 30. As a result, the direction switching valve 31 and each piston chamber 1
The direction switching valve 31 and the air cylinder 1 can be integrated without providing a pipe line communicating with the air cylinders 2 and 19 outside the air cylinder 1. Therefore, the pipeline is not obstructed when the air cylinder 1 is installed, so that the degree of freedom in installing the air cylinder 1 can be improved.
Further, since it is not necessary to consider the installation of the direction switching valve 31 when installing the air cylinder 1, the installation of the air cylinder 1 can be easily performed. Further, since no pipe line is provided outside the air cylinder 1, reliability against failure can be improved. Moreover, the appearance of the air cylinder 1 can be improved.

It should be noted that the present invention is not limited to the above-described embodiment, but can be configured as follows. (1) In the first embodiment, the piston hole 3 is not limited to the oval cylinder tube 2,
As shown in (a) and (b), the piston hole 3 may be implemented in the cylinder tube 2 having a circular shape.

(2) As shown in FIGS. 5A and 5B, the air cylinder 1 of the type in which a pair of parallel piston rods 10 are fixed to the same piston 11 is used. May be.

(3) As shown in FIGS. 6 (a) and 6 (b), a pair of piston holes 3 are formed in parallel in the same cylinder tube 2, and the piston 1 is provided in each piston hole 3.
1 and the piston rod 10 may be arranged and both piston rods 10 may be connected to drive the air cylinder 1. In this air cylinder 1, each cylinder hole 3
Each rod-side piston chamber 12 is communicated with the through hole 4D via the flow path 14. Further, each head side piston chamber 19 of each cylinder hole 3 is communicated with the head side port 23 via the flow path 22.

(4) As shown in FIGS. 7 (a), 7 (b) and 8, the rod cylinder 40 may be used instead of the rod cover 5 as the rod piece in the air cylinder 1 of the type. . In this case, the flow path 41 extending from the through hole 4D to the outer peripheral surface of the rod metal 40 in the radial direction of the cylinder tube is formed. Then, in the rod metal 40, a flow channel 42 that connects the flow channel 41 and the rod-side piston chamber 12 is formed. The cylinder tube 2 of the air cylinder 1 is formed by casting or forging metal.

(5) As shown in FIGS. 9 (a), 9 (b) and FIG. 10, the air cylinder 1 of the type using a metal type rod piece 43 instead of the rod cover 15 as a head piece is used. May be. In this case, the head side port 23 is provided on the outer peripheral surface of the head side end portion of the cylinder tube 2, and the flow path 44 is provided between the head side port 23 and the head side piston chamber 19.

(6) FIGS. 11 (a), 11 (b) and 12
As shown in (5) above, the rod-side port 2
1 is provided at the head side end of the through hole 4A, and the head side port 23 is provided at the head side end of the through hole 4D.
Then, the through hole 4D and the head side piston chamber 19 may be configured to communicate with each other through the flow path 45.

(7) As shown in FIGS. 13A and 13B, the rod cover 5 is provided with the rod side port 21 and the head side port 23, and the rod side port 21 supplies and exhausts the rod side piston chamber 12. Alternatively, the air may be supplied to and exhausted from the head side port 23 to the head side piston chamber 19 via the through hole 4D.

(8) In the second embodiment, FIG.
As shown in FIG. 4, the direction switching valve 31 may be attached to the outer surface 15a of the head cover 15. In this case, in the head cover 15, for each port of the directional control valve 31, a flow passage 32 communicating the through hole 4D, a flow passage 33 communicating the head side piston chamber 19, a flow passage 35 communicating the air supply port, And the flow path which connects each silencer 36, 37 is formed, respectively.

(9) As shown in FIG. 15, the direction switching valve 31 may be attached to the outer surface 15b of the head cover 15. (10) In each embodiment and each example, the rod side port 21 may be provided on each side surface other than the upper surface of the head cover 15. Further, the head side port 23 is connected to the head cover 1
It may be provided on each side surface other than the upper surface of 5.

(11) In the first and second embodiments, the through holes 4A to 4D are formed in the four corners 2A to 2D of the cylinder tube 2, respectively.
It is also possible to form only three through holes 4A and 4C into which 18 is screwed and through hole 4D serving as a transfer channel.

(12) In each of the first and second embodiments, the fixing bolts 8 and 18 are screwed into the two through holes 4A and 4C, but the through holes 4B that are not used as transfer passages are provided. Alternatively, the fixing bolts 8 and 18 may be screwed together. Therefore, the rod cover 5 and the head cover 15 are fixed at three places.

(13) The two through holes 4B and 4D may be used as transfer passages. That is, the rod cover 5 is formed with a passage that connects the through hole 4B serving as the transfer passage and the head side piston chamber 12, and the through hole 4D serving as the transfer passage and the head piston chamber 12 are communicated with each other. Forming a flow path. Also, the head cover 15 has
A flow path that connects the rod-side port 21 to the through hole 4B is formed, and a flow path that connects the rod-side port 21 to the through hole 4D is formed. According to this configuration, each through hole 4
Since a large flow passage cross-sectional area can be obtained without increasing the inner diameters of B and 4D, the cylinder tube 2 can be further downsized while driving the piston 11 at high speed.

(14) Through hole 4 used as a transfer channel
The inner diameter of D may be different from the inner diameters of the through holes 4A to 4C forming the female screw portion. (15) The cylinder tube 2 may be formed by metal casting or forging. In this case, the through holes 4A to 4D may be formed at the same time, or may be formed by machining in the secondary processing.

(16) The operation was performed on the air cylinder 1,
Alternatively, it may be implemented in a fluid cylinder such as a hydraulic cylinder. The technical ideas other than the claims that can be grasped from the embodiment will be described below together with their effects.

(1) In the fluid pressure cylinder according to the first aspect, the two through holes 4B and 4D are used as transfer passages.
With such a configuration, a large flow passage cross-sectional area can be obtained without increasing the inner diameters of the through holes 4B and 4D.

[0048]

As described above in detail, according to the first aspect of the invention, the working fluid is supplied to and discharged from the head side piston chamber and the rod side piston chamber by either the head piece or the rod piece. In addition, a large supply / exhaust amount of the working fluid can be obtained without increasing the size of the cylinder tube. Therefore, the speed of the piston can be increased without increasing the size of the air cylinder to obtain a large flow passage cross-sectional area.

According to the invention of claim 2, claim 1
In addition to the effect of the invention described in (1), the directional control valve and the fluid pressure cylinder can be integrated without providing a pipe line that connects the directional control valve and the fluid pressure cylinder. Therefore,
The degree of freedom of installation can be improved.

According to the invention of claim 3, claim 1
Alternatively, in addition to the effect of the invention described in claim 2, since the through hole can be simultaneously formed at the time of extrusion molding of the cylinder tube, the processing cost can be reduced.

[Brief description of the drawings]

FIG. 1 is an exploded perspective view of an air cylinder according to a first embodiment.

2A is a front view, and FIG. 2B is a sectional view taken along line AA of FIG.

FIG. 3A is a rear view of the air cylinder of the second embodiment, and FIG. 3B is a sectional view taken along line BB of FIG.

FIG. 4A is a front view of an air cylinder of another example,
(B) is a sectional view taken along line CC of (a).

FIG. 5A is a front view of an air cylinder of another example,
(B) is the DD sectional view taken on the line of (a).

6A is a front view of an air cylinder of another example, FIG.
(B) is a sectional view taken along line EE of (a).

FIG. 7A is a front view of an air cylinder of another example,
(B) is the FF sectional view taken on the line of (a).

8 is a sectional view taken along line GG of FIG.

FIG. 9A is a front view of an air cylinder of another example,
(B) is a sectional view taken along line HH in (a).

FIG. 10 is a sectional view taken along line I-I of FIG.

FIG. 11A is a rear view of an air cylinder of another example,
(B) is a sectional view taken along line JJ of (a).

FIG. 12 is a sectional view taken along line KK of FIG.

FIG. 13 (a) is a front view of another example of an air cylinder,
(B) is the LL sectional view taken on the line of (a).

FIG. 14A is a rear view of an air cylinder of another example,
(B) is a sectional view taken along line MM of (a).

FIG. 15A is a rear view of an air cylinder of another example,
(B) is the NN sectional view taken on the line of (a).

FIG. 16 is an exploded perspective view of a conventional air cylinder.

FIG. 17 is a side sectional view of the air cylinder of the same.

[Explanation of symbols]

2 ... Cylinder tube, 2A-2D ... Corner, 4A-4C
... through hole, 4D ... through hole as transfer passage, 5 ... rod cover as rod piece, 15 ... head cover as head piece, 31 ... two-position 5 as direction switching valve
Port direction switching solenoid valve.

Claims (3)

[Claims] 1. A substantially quadrangular shape having corners (2
A to 2D) is a fluid pressure cylinder provided with a cylinder tube (2) having through holes (4A to 4D) for fixing the rod piece (5) or the head piece (15), respectively. 4D), at least one of the through holes (4A to 4D) is provided between the rod piece (5) and the head side piston chamber (19), or between the head piece (15) and the rod side piston chamber (19). 12) A fluid pressure cylinder used as a transfer passage (4D) for supplying / exhausting a working fluid to / from. 2. The fluid pressure cylinder according to claim 1, wherein a direction in which working fluid is switched to be supplied to and exhausted from the rod side piston chamber (12) or the head side piston chamber (19) via the transfer passage. Replace the switching valve (31) with the headpiece (1
5) or a fluid pressure cylinder integrally provided on either one of the rod pieces (5). 3. The fluid according to claim 1, wherein the cylinder tube (2) is formed by extrusion molding of metal, and the through holes (4A-4D) are formed during extrusion molding. Pressure cylinder.