JPS62141959A - Magnetic actuator - Google Patents

Abstract

PURPOSE:To eliminate scattering of wearing powder in a magnetic actuator by providing a pair of first magnets attracted to a driver and a movable element, and a pair of second magnets repelling from each other to moving the element in noncontacting state. CONSTITUTION:A movable element 12 moves without contact with a cylinder 1. First magnets 9, 14 attract each other, and when a driver 8 moves in a cylinder 1 by a ball thread mechanism 5, the element 12 is driven by the driver 8 by the attracting force to move. Second magnets 10, 15 repel from each other, the element 12 is energized radially outward of the cylinder 1. As a result, the element 12 and the cylinder 1 coincide at their axial lines to always obtain a gap 18 of a predetermined uniform interval over the entire peripheral direction of the cylinder 1 between the element 12 and the outer surface of the cylinder.

Description

DETAILED DESCRIPTION OF THE INVENTION "Field of Industrial Application" The present invention relates to a magnetic actuator, and particularly to a magnetic actuator that allows a movable body to move in a non-contact manner.

``Prior Art'' Actuators, which are widely used as a means of conveying goods or as a power source for various power devices and control devices, include devices that directly actuate pistons and rods using air pressure or hydraulic pressure. Magnetic actuators that use magnetic force are also known.

FIG. 5 shows an example of such a magnetic actuator. This magnetic actuator: By making the driving body disposed inside the cylinder a hyperactive by pneumatic or hydraulic pressure, the annular movable body C disposed outside the cylinder a is moved by the magnetic force. The movable body C is used to transport articles, for example, or to use the hypermobile body C as a power source for various purposes.

In this magnetic actuator, both ends jM3 of the cylinder a
The driving body is caused to reciprocate in the direction of the axis of the cylinder a by air or water supplied from supply pipes d and d connected to the cylinder a. This driving body is equipped with a plurality of magnets e and yokes f that are magnetized by the magnets, and the moving body C is equipped with magnets e and yokes f of the driving body. A magnet g that attracts each other...
, yoke h... are provided. As the drive body moves within the cylinder a, the movable body C is pulled by the attraction force of the magnets e, . . . , 1g, and thereby follows the drive body.

In this conventional magnetic actuator, since the movable body C is configured to slide on the outer surface of the cylinder a, lubricating oil is used to enable the movable body C to slide smoothly.

"Problems to be Solved by the Invention" By the way, in a magnetic actuator such as the one described above in which the moving body C slides on the outer surface of the cylinder a, no matter how much lubricant is used, it is impossible to completely prevent wear of the sliding parts. It cannot be prevented. Then, the abrasion powder generated by the wear is scattered around the actuator, and the lubricating oil itself is also scattered, which inevitably contaminates the area around the actuator. .

Therefore, if such an actuator is installed in a room that requires extremely high cleanliness, such as a clean room, the cleanliness of the room will decrease due to wear particles and lubricating oil. Therefore, conventionally, it has been impossible to directly install an actuator in such a room.

Note that this problem always occurs when using not only a magnetic actuator but also an actuator having a sliding portion.

This invention was made in view of the above circumstances, and an object of the present invention is to provide a magnetic actuator that can be used in clean rooms, etc., without causing abrasion particles or lubricating oil to be scattered around.

"Means for Solving the Problems" The present invention provides a method for providing a drive body disposed inside a cylinder and moving in the axial direction of the cylinder by a drive source, and an outer surface of the cylinder located outside the cylinder. a movable body that is disposed with a gap and moves in the axial direction of the cylindrical body following the drive body, and the drive body and the Ig drive body move the movable body to the The first of the pair driven by the driver
The present invention is characterized in that it is equipped with a pair of second magnets that secure the gap between the movable body and the cylindrical body by repelling or attracting each other.

"Operation" The magnetic actuator of the present invention causes the movable body to follow the drive body by the attractive force of the pair of first magnets, which are applied to the drive body and the movable body. Further, a gap is maintained between the movable body and the outer surface of the cylindrical body by the repulsion or attraction force of the pair of second magnets provided therein, and the movable body is moved in a non-contact state.

・One Embodiment" Hereinafter, an embodiment of this invention will be described with reference to FIGS. 1 to 71.
This will be explained with reference to the figures.

These figures show the schematic structure of the magnetic actuator A of this embodiment, and the reference numeral 1 in the figures indicates a cylinder. This cylinder I is formed of a non-magnetic material into a circular shape on one fold, and one end thereof (lower end in Fig. 1).
is closed in an airtight manner by a cap 2, and a motor casing 3 is attached to the other end (upper end). Inside this motor casing 3 is a motor 4.
A ball screw mechanism 5 is connected to a rotating shaft 4a of the motor 4 through a joint 6. The ball screw mechanism 5 includes a feed screw 5a that is supported at both ends by bearings 7.7 and is rotatably disposed in the center of the cylinder 1, and a nut 5 that is screwed onto the feed screw 5a.
When the feed screw 5a is rotated by the motor 4, the nut 5b is moved in the axial direction of the cylinder l (vertical direction in FIG. 1).

A driving body 8 is attached to the nut 5b of the ball screw mechanism 5. The drive body 8 consists of a first magnet and two second magnets 10, 10 arranged above and below the first magnet. These first and second magnets 9, 10, 10 are each formed in an annular shape, and their inner peripheral surfaces are fixed to the nut 5b with a predetermined distance maintained by spacers 11.11. , 10. The outer peripheral surfaces of the cylinders 10 and 10 can slide on the inner surface of the cylinder 7. As shown in detail in FIG. 2, the first magnet 9 is composed of two permanent magnets 9a, 9a and three yokes 9b placed between them.・・・
- are N poles and N poles by permanent magnets 9a and 9a, respectively.
It is magnetized to S pole and N pole. Further, the second magnet 1
0.10 consists of a permanent magnet 10a... and a yoke 10b that sandwiches them, and this yoke lOb...
・They are respectively magnetized to N pole, S pole, and N pole.

Furthermore, a movable body 12 is disposed outside the cylinder l. This moving body I2 includes a first magnet 14 formed inside a tubular body 13 in an annular shape, each of which has an inner diameter slightly larger than the outer diameter of the cylinder l, and two second magnets 15.1.
5 are attached at a predetermined distance using spacers 16.

This first magnet 14 is connected to the first magnet 9 in the driving body 8.
Similarly, the yoke l 4 b- is made into an annular shape by the permanent magnets 14a, 14a, and the yoke l4b- is set to S pole, N pole, S+? i1. It is designed to be. Further, the second magnets 15, 15 have a configuration in which a permanent magnet and an electromagnet are combined. That is, this second magnet +5° 15 is connected to a plurality of (eight in this embodiment) yokes 15a that protrude inside the tubular body 13 and are attached radially, as shown in detail in FIGS. 2 to 4. . . . and permanent magnets 15b fixed to the upper and lower tips of the yoke 15a, respectively.
..., and a coil 15c attached around the center of the yoke 15a and magnetizing the yoke.
It is made up of. The yokes 15a... are configured such that their tips become N poles, S poles, and N poles, respectively, by permanent magnets 15b... and coils 15c..., and the coils 15c... The magnetic force can be controlled.

In addition, a second
Two gap sensors 17.17 are mounted at the positions of the magnets 15.15, respectively. These gap sensors + 7.17 are installed at positions such that their central angles are 90 degrees in plan view (
(See Figure 3).

The moving body 12 configured as described above has the cylinder I sandwiched between the first and second magnets +4.15.15 or the first and second magnets 9, 10.10 of the driving body 8. They are arranged to face each other (see Figure 2). As is clear from the polarity shown in FIG.
, I, 1 attract each other, and the second magnets 10.15 repel each other.

In addition to the above configuration, the magnetic actuators 7~
This allows the moving body 12 to move without contacting the cylinder I. That is, since the first magnets 9 and 14 attract each other, when the driving body 8 moves within the cylinder 1 by the ball screw mechanism 5, the movable body 12 is driven by the driving body 8 due to the attraction force. Hyperactive. Further, since the second magnets 10.15 repel each other, the movable body 12 is urged radially outward of the cylinder 1, and as a result, the axes of the movable body 12 and the cylinder 1 coincide with each other. It is possible to always maintain a gap 18 at a predetermined interval between the movable body 12 and the outer surface of the cylinder over the entire circumferential direction of the cylinder 1.

When an external force is applied to the moving body 12 and the dimensions of the gap 18 change, the change is detected by the gap sensor 17.17, and based on the detection result, a predetermined control device (not shown) is activated. By controlling the current value of the coil 15c, the second magnet 15.
15 can be controlled, and therefore the size of the gap 18 can always be kept at a constant value.

As mentioned above, in this magnetic actuator A,
Since there is no part of the moving body 12 that always slides in a non-contact state with the cylinder 1, there is no wear at all. Also,
Therefore, no lubricant is required. Therefore, unlike conventional actuators, there is no abrasion powder or lubricant oil that is scattered and does not contaminate the surrounding area. For this reason, it becomes possible to install it even in highly clean rooms such as clean rooms, which could not be installed conventionally.

Note that inside the 7-cylinder I, the feed screw 5a and the nut 5b, as well as the inner surface of the cylinder I and the outer peripheral surface of the driver 8, are in contact with each other, so there is a risk that they will wear out. Since the inside of the cylinder 1 is sealed by the cap 2 and the motor casing 3, wear particles and lubricating oil will not scatter to the outside of the cylinder 1.

Although the embodiments of this invention have been described above, this invention is not limited to the above embodiments, and the configuration of each magnet and its polarity may be changed as appropriate without being limited to the above, and various applications can be considered. It will be done.

For example, in the above, the second magnet of the moving body is configured to be a combination of a permanent magnet and an electromagnet, but this does not require the use of a permanent magnet (it may also be configured with only an electromagnet, or the first magnet may also be configured using only an electromagnet). Instead of using a permanent magnet, it may be configured by a combination of a permanent magnet and an electromagnet, or only an electromagnet, like the second magnet.

In addition, in the above, the magnet on the driving body side is made up of a permanent magnet, and the magnet on the moving body side is a combination of a permanent magnet and an electromagnet. Made only by
The magnet on the movable body side may be a permanent magnet. In this case, it is also possible to make the weight of the moving body lighter than in the case of the above embodiment.

Furthermore, although the second magnets are described above as repelling each other, the gap can be similarly secured even if the second magnets are attracted to each other. In this case, one of the second magnets (on the driving body side or on the movable body side) may be made of a magnetizable material, such as a piece of iron, instead of being a magnet.

Furthermore, the shape of the cylinder is not limited to a circular cross section, but may be a rectangular cross section, for example, and in that case, the driving body and the movable body may also have shapes corresponding to the shape of the cylinder. In the above, a ball screw mechanism was used as the drive source for the drive body, but the drive body is not limited to this, and any suitable means may be used, such as driving by a wire or chain, or driving using hydraulic pressure or air pressure. You can do it from

Third, this magnetic actuator can be used with the cylinder vertically to move the moving body up and down, or can be used with the cylinder horizontally or in any direction.

1. Effects of the Invention" As explained in detail below, in the magnetic actuator of the present invention, the driving body and the movable body have a pair of first magnets that attract each other and a pair of first magnets that repel or attract each other. Since the actuator is equipped with two magnets, it is possible to move the moving object in a non-contact manner, and there is no need to use lubricating oil as there is no wear powder scattered like with conventional actuators) From that i12'J Nameura there is no scattering. However, there is a risk that the prying actuator may contaminate the surrounding area.
This has the effect that it can be installed indoors in a 1a'' room.

[Brief explanation of drawings]

1 to 4 are diagrams showing embodiments of the present invention. FIG. 1 is a cross-sectional view showing the overall schematic configuration of the magnetic actuator of this embodiment, FIG. 2 is an enlarged cross-sectional view of the main parts thereof, FIG.
The figure is a plan cross-sectional view taken along line IV iV in FIG. 2. Fig. 5 is a schematic diagram of a conventional magnetic actuator ((a sectional view without showing the structure). A... Magnetic actuator, 1... Cylinder (
Cylindrical body), 5...Ball screw mechanism (drive source), 8...
Drive body, 9.14...first magnet, I O, 15
...Second magnet, 12-...Moving object, I8...
·gap. Withdrawal; Deposit Yoshikawajima Hari 1 Go Heavy Industries (representative of unformed company)＼
Yoshi IY Masaru C)
, shi, no Figure 2

Claims (1)

[Claims] A drive body disposed inside the cylinder and moved in the axial direction of the cylinder by a drive source, and a drive body disposed outside the cylinder with a gap between the outer surface of the cylinder and driven by the drive body. and a movable body that moves in the axial direction of the cylindrical body, and the drive body and the movable body are provided with a pair of first magnets that attract each other to cause the movable body to follow the drive body. and a pair of second members that secure the above-mentioned gap between the movable body and the cylindrical body by repelling or attracting each other.
A magnetic actuator characterized by being equipped with a magnet.