JPH0788843B2 - Rodless cylinder device - Google Patents

Description

The present invention relates to a rodless cylinder device that operates by hydraulic pressure.

[Conventional technology and its problems]

Conventionally, a cylinder device that operates with a pneumatic cylinder or a hydraulic cylinder has been used to linearly reciprocate a load, and a rodless cylinder device without a piston rod is used especially in a narrow space. .

As a conventional rodless cylinder device, a piston driven axially in a cylinder tube by a pressure fluid,
A load driving body that can move in the axial direction on the outer circumference of the cylinder tube is provided, and a permanent magnet group is provided in each of the piston and the load driving body, and the attraction force (including repulsive force) between these permanent magnet groups is used. It is known that the load driving body is configured to move following the piston (for example, Japanese Utility Model Publication No. 57-45442).

However, in the conventional device, as the permanent magnet group, a plurality of annular magnets that are magnetized in the axial direction are arranged in the axial direction, so the attraction force between these permanent magnet groups is not always sufficient. The driving force of the piston could not be sufficiently transmitted to the load driver.

Further, in order to increase the attraction force, a large number of annular magnets must be arranged in the axial direction, so that the axial dimension of the cylinder device becomes large, and the advantage of the rodless cylinder device is impaired. There was a problem.

[Technical means for solving problems]

The present invention has been made in view of the above problems, and an object thereof is to provide a rodless cylinder device capable of suppressing a large attraction force between permanent magnet groups and an increase in axial dimension, and technical means therefor. Has a piston that is axially driven in the cylinder tube by a pressure fluid, and a load driver that is axially movable on the outer circumference of the cylinder tube, and the piston and the load driver each have a permanent magnet. In a rodless cylinder device in which a group is provided and the load driving body moves following the piston due to the attraction force between the permanent magnet groups, at least one of the permanent magnets on the piston side or the load driving body side is permanent. The magnet group includes two drive magnets that are magnetized in the axial direction and are arranged with a constant gap in the axial direction so that the same poles face each other. Radially magnetized and between the two driving magnets, characterized by comprising an auxiliary magnets disposed so as to these and homopolar.

[Work]

The drive magnets magnetized in the axial direction are arranged so that the same poles face each other, and a magnetic pole is generated between the drive magnets facing each other.

The drive magnets magnetized in the radial direction are arranged between the drive magnets magnetized in the axial direction and have the same poles as the magnetic poles generated between the drive magnets magnetized in the axial direction. The three magnetic poles are surrounded by the same poles, so that the magnetic force lines are concentrated only in one radial direction and a strong attractive force is generated.

〔Example〕

 Embodiments of the present invention will be described below with reference to the drawings.

The drawing is a front sectional view of the rodless cylinder device 1.

The rodless cylinder device 1 includes a cylinder tube 2 made of a non-magnetic material, cylinder covers 3 and 4 closing both ends of the cylinder tube 2, and a cylinder tube 2 made of a pressurized fluid.
The piston 5 driven in the axial direction inside, and an annular load drive body 6 that is axially movable around the outer circumference of the cylinder tube 2.
Etc.

A permanent magnet group 7 composed of a plurality of annular permanent magnets 8, 9, 10 ... Is attached to the piston 5 by a shaft bolt 11 and a nut 12 via a plate 5a. , A plurality of annular permanent magnets 1 similar to the piston 5
The case tube 17 includes the permanent magnet group 13 composed of 4, 15, 16 ...
And it is attached by being sandwiched between the side plates 18, 18 screwed to this. Between the permanent magnets, spacer members 19 made of a non-magnetic material for holding the position of the permanent magnets are provided.

In the permanent magnet group 7 on the piston side, the permanent magnets (hereinafter referred to as “driving magnets”) 8, 9 ... Which have a larger diameter, that is, closer to the cylinder tube 2, are axially magnetized and The permanent magnets (hereinafter referred to as "auxiliary magnets") 10 having the same poles facing each other and having a smaller diameter, that is, the one farther from the cylinder tube 2 are magnetized in the radial direction and are driven as described above. The magnets 8, 9 ... Are arranged so as to have the same poles as those.

In the permanent magnet group 13 on the load driver side as well as on the piston side, the permanent magnets (driving magnets) 14, 15 ... Close to the cylinder tube 2 are axially magnetized and have the same polarity as each other. Are arranged so as to face each other, and the permanent magnets (auxiliary magnets) 16 ... Far from the cylinder tube 2 are magnetized in the radial direction and have the same pole as those between the drive magnets 14, 15. Are arranged as follows.

Furthermore, when the permanent magnet group 13 is located right above the permanent magnet group 7, the drive magnets 8,
The magnetic poles 9 ... And the drive magnets 14, 15 ... Have opposite poles.

Further, the cylinder covers 3 and 4 are provided with ports 21 and 24 for supplying pressurized fluid, communication passages 22 and 25, and recesses 23 and 26, and the piston 5 has a small diameter portion of the shaft bolt 11. An insertion hole 27 for inserting the 11a is provided. Incidentally, 28 is a washer, 29, 30, 31 are packings, and 32, 33 are cylinder chambers.

Next, the operation of the rodless cylinder device 1 configured as described above will be described.

First, the permanent magnet group 7 on the piston side will be described.
Since the drive magnets 8 and 9 have the same pole (S pole) facing each other, a magnetic pole of S pole is generated between them, and the S pole of the auxiliary magnet 10 faces here, and the S poles of the three sides are S poles. Since it is surrounded, magnetic field lines with high density are generated outward in the radial direction from here.

On the other hand, also in the permanent magnet group 13 on the load driver side, similarly to the piston side, a magnetic field line with high density is generated radially inward from the portion surrounded by the drive magnets 14 and 15 and the auxiliary magnet 16. .

Since the magnetic poles of these parts are different from each other, the magnetic force lines starting from one permanent magnet group 13 end in the other permanent magnet group 7, and conversely the magnetic force lines starting from the permanent magnet group 7 are in the permanent magnet group 13. At the end, extremely strong suction force is generated here.

When a pressurized fluid, for example, compressed air is supplied from one port 24, the compressed air passes through the communication passage 25 and the recess 26, and the cylinder chamber.
It flows into 33, and this pressure moves the piston 5 to the left in the figure. As the piston 5 moves, the permanent magnet group 7
And the permanent magnet group 13 and the magnetically attracted permanent magnet group 13 and the load driving body 6 move in the same direction.

When compressed air is supplied from the other port 21, the piston 5 moves in the opposite direction to the above, and the load driver 6 is driven accordingly.

Therefore, by attaching a load to the load driving body 6, the load can be linearly driven reciprocally in the axial direction.

Moreover, because the attractive force between both permanent magnet groups is extremely large,
The driving force of the piston 5 can be sufficiently transmitted to the load driving body 6.

Further, the auxiliary magnets 10 ... And the auxiliary magnets 16 ...
, And the drive magnets 14, 15 are arranged between the permanent magnet group 7 and the permanent magnet group 13, the dimension of the permanent magnet group 7 and the permanent magnet group 13 in the axial direction does not increase even though the attraction force is extremely large.

Therefore, the rodless cylinder device 1 having a large driving force and a small axial dimension can be obtained, and the rodless cylinder device 1 can be used in a narrow space, and the advantages of the rodless cylinder device 1 can be utilized.

In the above embodiment, the number of permanent magnets in each permanent magnet group 7, 13 can be increased or decreased. Drive magnets 8 and 9 and auxiliary magnet 1
You may arrange | position so that 0 and the axial direction may overlap. Auxiliary magnet 1
The 0 may be embedded in the shaft bolt 11. The auxiliary magnet of either the permanent magnet group 7 or the permanent magnet group 13 may be omitted. The mounting structure or the holding structure of the permanent magnet group 7 or the permanent magnet group 13 can be variously changed.

The present invention should include that the outer permanent magnet group 13 is the driving side and the inner permanent magnet group 7 is the driven side. Therefore, for example, a tube is provided on the outer circumference of the permanent magnet group 13 and a space between the tube and the cylinder tube 2 is used as a cylinder chamber, and a pressurized fluid is supplied to the cylinder chamber to supply permanent magnet group 13
It is not a departure from the technical idea of the present invention to drive the motor and to attach a load to the permanent magnet group 7 that follows it.

〔The invention's effect〕

According to the present invention, since the attraction force between the permanent magnet groups between the piston side and the load driving body side is extremely large, the driving force of the piston can be sufficiently transmitted to the load driving body.

In addition, since the auxiliary magnets are arranged between the drive magnets, the permanent magnet group does not have a large axial dimension even though the attraction force is extremely large, and the rodless rod has a large driving force and a small axial dimension. A cylinder device can be obtained, and the advantages of the rodless cylinder device can be utilized.

[Brief description of drawings]

The drawings are front sectional views showing an embodiment of the rodless cylinder device of the present invention. 1 ... Rodless cylinder device, 2 ... Cylinder tube, 5 ... Piston, 7 ... Permanent magnet group, 8,9 ... Driving magnet, 10 ... Auxiliary magnet, 13 ... Permanent magnet group, 14,15 ......
Drive magnet, 16 ... Auxiliary magnet.

Claims (1)

[Claims] 1. A piston, which is axially driven in a cylinder tube by a pressure fluid, and a load driver which is axially movable on the outer periphery of the cylinder tube. In a rodless cylinder device in which permanent magnet groups are respectively provided and the load driving body moves following the piston by an attraction force between the permanent magnet groups, at least on the piston side or the load driving body side. One of the permanent magnet groups is magnetized in the axial direction and is magnetized in the radial direction with two drive magnets arranged at a constant interval in the axial direction so that the same poles face each other. A rodless cylinder device, comprising: an auxiliary magnet arranged between the two drive magnets so as to have the same poles as those of the two drive magnets.