JP2858391B2 - Rodless 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 rodless cylinder which is a type of a fluid pressure actuator. The rodless cylinder of the present invention mounts a work such as a machine tool on a table, which is a component of the cylinder, and reciprocates the table together with the work by supplying fluid pressure.

[0002]

2. Description of the Related Art Japanese Patent Laid-Open Publication No.
In the invention of No. 0914, a yoke driven by a piston provided with a permanent magnet and a table are integrally formed.

[0003] However, if the yoke and the table are formed integrally, there is a problem that even if a high-precision commercial product is provided for the table, the commercial product cannot be used.

[0004]

SUMMARY OF THE INVENTION In view of the foregoing, it is an object of the present invention to provide a rodless cylinder that is commercially available for a table and that is cost-effective.

[0005]

To achieve the above object, a rodless cylinder according to a first aspect of the present invention includes a yoke driven by a piston provided with a permanent magnet, and a table connected to the yoke. The yoke and the table are disposed between the magnetic poles adjacent to each other, with the outer diameter of the head and the connecting member fitted to both members being set smaller than the distance between the magnetic poles inside the yoke. bolt
And it was decided that they were linked. In addition, the contract of the present invention
A rodless cylinder according to claim 2 is the rodless cylinder according to claim 1.
In the woodless cylinder, the shock absorbing mechanism is arranged on substantially the same plane as the connecting surface between the yoke and the table.

[0006]

If the yoke and the table are separated from each other and the two members are connected to each other, a commercially available table can be used. In the present invention, the following points are further noted. . When two parts are connected, an adapter is generally interposed between the two parts, so that the connection structure tends to be complicated, complicated and large. However, in the present invention, a simple and compact connection is used. I decided to aim for a structure. Therefore, in the present invention, the yoke and the table are directly connected by using the connecting member and the bolt. Care was taken that the coupling structure did not adversely affect the magnetic properties. For this reason, in the present invention, a bolt whose head outer diameter is set to be smaller than the interval between the magnetic poles inside the yoke and which is arranged between magnetic poles adjacent to each other is used. The formation of a closed magnetic circuit was not hindered. Even if a large work (mass of inertia) is mounted on the table, the structure is designed to be able to withstand the impact of stopping. Therefore, in this invention, in addition to the bolt to be used "<br/> coupling member is fitted to both members", by the coupling member, and to receive the shearing force generated in the connecting portion by the impact. In addition, since a small bolt having a relatively small strength is used as described above, the connecting member has an action of reinforcing the strength. Also, when the shock absorbing mechanism is arranged on substantially the same plane as the connecting surface between the yoke and the table,
It is possible to prevent a large rotational moment from being generated in the connecting portion due to the impact.

[0007]

Next, an embodiment of the present invention will be described with reference to the drawings.

As shown in FIGS. 1 to 4, a linear guide 3 and a cylinder 4 are provided between a pair of end plates 1 and 2.
And the magnetic proximity switch mounting rails 5 are installed in parallel with each other. When the piston 7 of the cylinder 4 inserted in the cylinder tube 6 reciprocates, the pulling force of the permanent magnet 8 provided on the piston 7 causes the cylinder to move. A yoke 9 made of a magnetic material extrapolated to the tube 6;
, The table 10 of the linear guide 3 connected to is driven. The table 10 is also supported and guided by a guide rail 11 of the linear guide 3, and the guide rail 1
A work (not shown) such as a machine tool is mounted on the table 10. As described above, the eyes of the present invention include the table 10 and the guide rail 1.
In the case where a high-precision commercial product is provided for the linear guide 3 made of No. 1, the commercial product can be effectively used.

The cylinder 4 has a pair of end covers 12 and 13 hermetically fitted to the end of a cylinder tube 6 made of a non-magnetic material such as stainless steel.
2 and 13 are hermetically fitted to the end plates 1 and 2, and a pair of pressure supply ports 14 and 15 are formed by a series of holes formed in the end plates 1 and 2 and the end covers 12 and 13. Is provided. Hard chrome plating treatment (not shown) on the outer peripheral surface of the cylinder tube 6
Is given.

A piston 7 is inserted into the cylinder tube 6. This piston, generally designated by the reference numeral 7, has a pair of piston members 16 and 17 integrally assembled by a tie rod 18 and nuts 19 and 20 made of a non-magnetic material. In between, a required number (seven in the figure) of magnetic pole members 21 made of a magnetic material and a required number (six in the figure) of permanent magnets 8 having a ring are sandwiched in a state of being alternately arranged in the axial direction. It is rare.
The permanent magnet 8 has its north and south poles disposed at axial ends, and two permanent magnets 8 facing each other with one magnetic pole member 21 facing each other with the same polarity. A wear ring 22 and a seal 23 are attached to the piston members 16 and 17.
Is mounted to keep the piston 7 coaxial with the cylinder tube 6 and to set a predetermined gap between the magnetic pole member 21 and the cylinder tube 6 and between the permanent magnet 8 and the cylinder tube 6.

A yoke 9 made of a magnetic material is externally inserted into the cylinder tube 6. On the inner peripheral surface of the through hole 9a of the yoke 9 through which the cylinder tube 6 is inserted, the same number of magnetic projections 9b as the number of magnetic pole members 21 are provided integrally with each other in the axial direction, and the yoke 9 is adjacent to each other. Combined magnetic poles 9b, 9
The interval x (see FIG. 4) of b is set substantially equal to the interval between the magnetic pole members 21 and 21 adjacent to each other with the permanent magnet 8 interposed therebetween.
A magnetic pole member 21 in contact with the pole, a magnetic pole 9b opposed to the outer peripheral side of the magnetic pole member 21 via the cylinder tube 6,
The main body of the yoke 9, the adjacent magnetic pole 9 b, the magnetic pole member 21 facing the inner peripheral side of the magnetic pole 9 b via the cylinder tube 6, and the S of the permanent magnet 8 in contact with the magnetic pole member 21.
A closed magnetic circuit surrounding the poles is formed, and thus a closed magnetic circuit is formed.
The magnetic force of the permanent magnet 8 is effectively used as much as possible as a pulling force for pulling the yoke 9. The magnetic poles 9b, 9b adjacent to each other are recessed by medium machining to prevent magnetic leakage. A pair of wear rings 24 are attached to the yoke 9 to keep the magnetic pole 9 b coaxial with the cylinder tube 6 and to set a predetermined gap between the magnetic pole 9 b and the cylinder tube 6. At the end of the wear ring 24, a scraper (not shown) for preventing dust from entering the through hole 9a is provided.

The linear guide 3 composed of the table 10 and the guide rail 11 is commercially available as an assembled assembly that travels with extremely high precision because a linear motion bearing 25 is incorporated between the two members 10 and 11. The rodless cylinder is a combination of this assembled commercial assembly and other parts. In particular, the table 10 and the yoke 9
key groove-shaped fitting recesses 10b, 9d provided in
A key-shaped connecting member 26 is fitted to each
A required number (two in the figure) of bolt insertion holes 9e are provided in the yoke 9.
Is provided, and the bolt 27 is screwed into the connection. The bolt insertion hole 9e is drilled from the front outer wall 9f side of the yoke 9 and crosses the through hole 9a at right angles. Therefore, if a part of the magnetic pole 9b provided on the inner peripheral surface of the through hole 9a is shaved by the drilling of the bolt insertion hole 9e, the closeability of the magnetic circuit described above is impaired and magnetism leaks. Therefore, the magnetic properties are adversely affected. To prevent this, it is necessary to take care not to cut the magnetic pole 9b when drilling the bolt insertion hole 9e. To make this possible, the bolt insertion hole 9e intersects with the through hole 9a. Therefore, the width y of the bolt insertion hole 9e is changed as shown in FIG.
The distance x between the magnetic poles 9b adjacent to each other must be smaller than x. In order to enable this, the bolt insertion hole 9e is provided for inserting the bolt 27, so that the maximum of the bolt 27 is required. The outer diameter, that is, the outer diameter of the head 27a of the bolt 27, must be smaller than the distance x between the adjacent magnetic poles 9b, 9b. Therefore, by setting the outer diameter of the head 27a of the bolt 27 to be smaller than the distance x between the magnetic poles 9b and arranging the bolt 27 and the bolt insertion hole 9e between the magnetic poles 9b adjacent to each other, the magnetic characteristics can be improved. The adverse effects can be prevented. Bolt 27
Is formed of a non-magnetic material to prevent magnetic leakage. Although the connection member 26 is illustrated assuming a square block, the connection member 26 may be a columnar or other pin-shaped member. The number of the bolts 27 and the connecting members 26 to be mounted and the number of the mountings are not particularly limited, and the fitting recesses 10b and 9d or the bolt insertion holes 9e corresponding to the numbers are formed.

The guide rail 11 has, at its end,
As shown in FIG. 3, it is fitted into the concave portion 1a of the end plates 1 and 2. Also, the guide rail 11 has its lower surface 1
In FIG. 1a, as shown in FIGS. 2 and 3, it protrudes below the lower surfaces 1b, 2a of the end plates 1, 2, whereby the lower surface 11a of the guide rail 11 serves as a reference mounting surface for the rodless cylinder. Used. A pair of stopper blocks 28
29, the stopper blocks 28, 29
A shock absorbing mechanism 30, such as a hydraulic shock absorber,
31 is attached and faces a pair of stoppers 32 and 33 attached to the side surface of the yoke 9. Regarding the reciprocating direction of the table 10, the stopper blocks 28, 2
9 is capable of adjusting the mounting and fixing position with respect to the guide rail 11, and the shock absorbing mechanisms 30 and 31 are provided with the stopper block 2.
The mounting and fixing positions can be adjusted with respect to 8, 29, and within these adjustable ranges, it is possible to adjust the reciprocation limits of the yoke 9 and the table 10. Shock absorbing mechanism 3
The 0 and 31 and the stoppers 32 and 33 are arranged on substantially the same plane as the connecting surfaces 9 c and 10 a of the yoke 9 and the table 10.

When operating the rodless cylinder having the above-described structure, mounting bolts (not shown) are inserted into mounting holes 34 provided in the guide rail 11 and the end plates 1 and 2 so that the rodless cylinder is fixed to a predetermined position. Bolts and pressure supply ports 14, 15
Is connected to a pressure supply pipe (not shown), and the fixing positions of the stopper blocks 28 and 29 and the shock absorbing mechanisms 30 and 31 are adjusted, and a magnetic proximity switch (not shown) is mounted on the magnetic proximity switch mounting rail 5. The work is mounted on the table 10. When fluid pressure (pneumatic pressure) is supplied from one pressure supply port 14 into the cylinder 4, the piston 7 moves toward the other pressure supply port 15, and the yoke is pulled by the pulling force of the permanent magnet 8 provided in the piston 7. 9, the table 10 and the work follow, and the stopper 33
When these abut against the shock absorbing mechanism 31, these movements are stopped. Next, when the fluid pressure is discharged from one pressure supply port 14 and the fluid pressure is supplied into the cylinder 4 from the other pressure supply port 15, the piston 7 moves toward the one pressure supply port 14, and the permanent magnet 8 When the yoke 9, the table 10 and the work are driven by the pulling force of
The movement is stopped, and this reciprocation is repeated as needed.

This embodiment has the following functions and effects. Since the yoke 9 and the table 10 of the linear guide 3 are separated from each other and the two members 9 and 10 are connected to each other, when a high-precision commercial product of the linear guide 3 is provided, this commercial product is used. Is possible. Therefore, it is possible to provide a cost-effective product that effectively utilizes this commercial product. The yoke 9 and the table 10 of the linear guide 3 are directly
Because of the connection, the connection structure is simple and compact. Therefore, a compact product can be provided despite the separate yoke 9 and table 10. The bolt 27 connecting the yoke 9 and the table 10 of the linear guide 3 has an outer diameter of the head 27a set to be smaller than the distance x between the magnetic poles 9b inside the yoke 9 and is disposed between the magnetic poles 9b adjacent to each other. The bolt 27 does not hinder the formation of a closed magnetic circuit. Therefore, the magnetic force of the permanent magnet 8 can be effectively used to the maximum, and a product having a large traction force can be provided. Further, since the small permanent magnet 8 can be used, the product can be made compact from this aspect as well. Since the yoke 9 and the table 10 of the linear guide 3 are connected using the “connecting member 26 fitted to both members ” in addition to the bolt 27, the shearing force generated at the time of stoppage is generated by the connecting member 26. Can be received. Therefore, it is possible to provide a product that can sufficiently withstand the impact at the time of stoppage, despite the fact that a small bolt having a not so large strength is used for the bolt. The shock absorbing mechanisms 30 and 31 are connected to the yoke 9 and the table 10.
Are arranged on substantially the same plane as the connecting surfaces 9c and 10a, it is possible to prevent a large rotational moment from being generated at the time of stopping. Therefore, it is not necessary to set the strength capable of coping with the large rotational moment in each part. The shock absorbing mechanisms 30, 31 may be attached to the end plates 1, 2, and the stoppers 32, 3
3 may be reversed and attached to the yoke 9.

[0016]

The present invention has the following effects.

That is, first, the rodless cylinder according to the first aspect of the present invention having the above configuration has the following effects. Since the yoke and the table are separated and the two members are connected to each other, when a high-precision commercial product is provided for the table, this commercial product can be used. Therefore, it is possible to provide a cost-effective product that effectively utilizes this commercial product. Since the yoke and the table are directly connected, the connection structure is simple and compact. Therefore, a compact product can be provided despite the separate yoke and table. For the bolt connecting the yoke and the table, the outer diameter of the head is set to be smaller than the distance between the magnetic poles inside the yoke, and a bolt arranged between magnetic poles adjacent to each other is used. It does not hinder the formation of a closed magnetic circuit. Therefore, the magnetic force of the permanent magnet can be effectively used to the maximum, and a product having a large traction force can be provided. In addition, since a small permanent magnet can be used, the product can be made compact from this aspect as well.

Since the yoke and the table are connected using the "connecting member fitted to both members " in addition to the bolt, the connecting member can receive the shearing force generated at the time of stopping. Therefore, it is possible to provide a product that can sufficiently withstand the impact at the time of stoppage, despite the fact that a small bolt having a not so large strength is used for the bolt.

Further, the rodless cylinder according to the second aspect of the present invention having the above configuration has the following effects.
Since the shock absorbing mechanism is arranged on substantially the same plane as the connecting surface between the yoke and the table, it is possible to prevent a large rotational moment from being generated at the time of stopping. Therefore, it is not necessary to set the strength capable of coping with the large rotational moment in each part.

[Brief description of the drawings]

FIG. 1 is a partially cutaway plan view of a rodless cylinder according to an embodiment of the present invention.

FIG. 2 is a rear view of the rodless cylinder.

FIG. 3 is a side view of the rodless cylinder.

FIG. 4 is a plan sectional view of a yoke.

[Explanation of symbols]

 1, 2 End plate 1a Recess 1b, 2a, 11a Lower surface 3 Linear guide 4 Cylinder 5 Magnetic proximity switch mounting rail 6 Cylinder tube 7 Piston 8 Permanent magnet 9 Yoke 9a Through hole 9b Magnetic pole 9c, 10a Connecting surface 9d, 10b Fitting recess 9e Bolt insertion hole 9f Front outer wall 10 Table 11 Guide rail 12, 13 End cover 14, 15 Pressure supply port 16, 17 Piston member 18 Tie rod 19, 20 Nut 21 Magnetic pole member 22, 24 Wear ring 23 Seal 25 Linear bearing 26 Connection Member 27 Bolt 27a Head 28, 29 Stopper block 30, 31 Shock absorbing mechanism 32, 33 Stopper 34 Mounting hole

Claims (2)

(57) [Claims] 1. A piston (7) provided with a permanent magnet (8).
And a table (10) connected to the yoke (9). The yoke (9) and the table (10) are fitted to both members (9) (10). Sa
The outer diameter of the connecting member (26) and the head (27a) is set smaller than the interval (x) between the magnetic poles (9b) inside the yoke (9), and the magnetic poles (9b) adjacent to each other are set. the bolts (27) disposed between, rodless cylinders, characterized in that it is connected. 2. The rodless cylinder according to claim 1, wherein the connecting surface (9c) between the yoke (9) and the table (10).
On substantially the same plane as (10a), the shock absorbing mechanism (30) (3)
A rodless cylinder, wherein 1) is disposed.