JPS60197155A - Operating device utilizing magnetic fluid - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an actuating device using magnetic fluid that controls the movement of a movable part using magnetic fluid.

Conventionally, the positioning of jigs and processing blades in processing machines has been performed using feed screws, but there is a limit to the feed accuracy. In recent years, for example, extremely high positional accuracy is required in the production of integrated circuit patterns, and the feed screw described above cannot meet this requirement. Various aerostatic screws have been proposed that attempt to achieve high feed accuracy by averaging.

However, the aerostatic screw has a long stroke and takes time to operate, so it is usually used only as a fine positioning device, and its structure is extremely complicated.

This invention was made based on the above circumstances,
It is an object of the present invention to provide an actuating device with a simple structure that can move with a long stroke and position with high feed accuracy.

The outline of the present invention for achieving the above object is that a piston-shaped movable part is movably provided inside a cylindrical fixed part, and the piston-shaped movable part is moved by magnetic fluid attracted by the excitation of a solenoid. That's true.

Next, the present invention will be explained with reference to examples.

FIG. 1 is a sectional view showing an embodiment of the present invention.

As shown in FIG. 1, the actuating device flit, which is an embodiment of the present invention, has a magnetic core 3, for example, one end of an iron member, inserted into an opening at one end of a cylindrical fixed part λ having both ends open. A solenoid is wound around the magnetic core 3 extending outward from the opening at one end of the fixed part.

The cylindrical fixing part can be formed into a cylindrical shape, for example, a cylindrical body with a circular cross section, a prismatic cylinder with a rectangular cross section, or a prismatic cylinder with a horizontally long rectangular cross section. This cylindrical fixing part λ is usually arranged horizontally. However, if necessary, this cylindrical fixing part may be arranged vertically or inclinedly.

The distal end j of the magnetic core 3 located within the cylindrical fixed portion λ is narrowed so that its end surface is smaller than the cross section of the central portion of the magnetic core 3. The reason why the tip S of the magnetic core 3 is squeezed in this way is to increase the density of magnetic lines of force and thereby make the attraction of the magnetic fluid, which will be described later, more efficient.

One end of the movable table B is inserted into the other end opening of the cylindrical fixed part λ, and the piston-shaped movable part 7 is attached to one end of the movable table 6. Piston-shaped movable part 7
An O-ring j is attached to the outer periphery of the cylinder, and the O-ring l allows the piston-shaped movable part 7 to move airtight within the cylindrical fixed part λ. Furthermore, the movable table 6 can be smoothly moved by a slide bearing ringer mounted within the cylindrical fixing part λ.

One end opening of a magnetic fluid supply pipe 10 is connected to the bottom surface near the tip j of the cylindrical fixing part, and the other end opening of the magnetic fluid supply pipe 10 is connected to a container filled with magnetic fluid ii. Insert into 12.

The inner wall of the cylindrical fixing part, the magnetic core 3
By removing air from the magnetic fluid chamber 13 formed by the tip j and the tip surface of the piston-like movable portion 7 facing the tip S, the magnetic fluid chamber lJ is filled with the magnetic fluid //. I'll keep it.

In addition, the tip part! The piston-shaped movable part 7 facing
As in this embodiment, the front end surface of the piston-shaped movable portion 7 is tapered from the center of the front end surface toward the magnetomotive fluid supply pipe 10, away from the end surface of the front end portion j. It is preferable to form 7mm. By forming these seven tapered surfaces, not only can the magnetic fluid // flow smoothly into the magnetic fluid chamber 13, but also the flowing magnetic fluid // can not collide with the tapered surface 7A. This is because the inflow pressure of the magnetic fluid can be converted into the pressing force of the piston-shaped movable part 7.

Next, the operation of the operating device configured as described above will be described.

In the initial state, it is assumed that the piston-shaped movable portion 7 is disposed close to the tip end j of the magnetic core 3.

When the solenoid is energized from a power source (not shown), the solenoid is energized and the magnetic core 3 is magnetized. The magnetic field produced by the magnetized magnetic core 3 attracts the magnetic fluid // in the container 1 and flows into the magnetic fluid chamber 13 . Due to the inflow of the magnetic fluid //, the piston-shaped movable part 7 receives a pressing force, and the piston-shaped movable part 7 moves forward within the cylindrical fixed part λ, thereby moving the movable table 6.

The amount of movement of this movable table B can be determined by the amount of magnetic fluid l/ flowing into the magnetic fluid chamber /3,
The amount of inflow of the magnetic fluid can be appropriately determined by the amount of current flowing through the solenoid and the time period for which the current is applied.

In order to move the moving table 6 that has moved forward backward, it is sufficient to stop the energization of the solenoid 6 and press the moving table t in the backward direction using other mechanical means. By such means, the piston-like movable part 7 moves back together with the moving table 6, and the magnetic fluid in the magnetic fluid chamber 13 flows into the container/2.

In this way, the movable table base is moved forward by the excitation of the solenoid l, and by delicately varying the amount of current supplied to the solenoid l, the amount of movement of the movable table base can be varied with high precision. Therefore, by using this moving table 6 as a processing table or as a positioning table, highly accurate positioning can be achieved.

Next, a second embodiment of the invention will be described.

As shown in FIG. 2, the actuating device 20 according to the second embodiment has a pair of first cylindrical fixing parts J/ and second cylindrical fixing part n that are open at both ends, so that the openings face each other. The ends of one movable table n are inserted into the respective openings, and each end is inserted into the first piston-like fixed part 2/, 22 within the first and second cylindrical fixing parts 2/, 22. The movable @ 211 and the second piston-shaped movable part 23 are fixed. One end of the first magnetic core d1 and the second magnetic core 9, into which the tip roller and core are squeezed, is fitted into the other end opening of each of the first and second cylindrical fixing parts J/, JJ, These first and second cylindrical fixing parts
A first solenoid 30.J is attached to the first and second magnetic cores J, 2 which extend outward from the opening at the other end of each J. Wind the second solenoid 3/. Further, the tip portions λ6, 2 of the first and second cylindrical fixing portions 1, 22
7, a first magnetic fluid supply pipe 32 is installed on the bottom near each
, and one end opening of the second magnetic fluid supply pipe 33 is connected to the first and second magnetic fluid supply pipes 3.

33 are inserted into a first container 3j that satisfies the first magnetic fluid evaluation and a second container 37 that is filled with a second magnetic fluid 3t. The actuating device 20 configured as described above excites the first solenoid 30 to cause the first solenoid to move from the first container 36 to the first solenoid.
The first magnetic fluid to the magnetic core,? When suctioning 4L,
The second magnetic fluid 3j is interposed between the second magnetic core 2 and the second piston-shaped movable part 2 by demagnetizing the second thread/id 31.
By discharging the liquid into the second container 37, the movable table sword 3 is moved in the direction of the arrow mark in FIG. When moving the moving table 8 in the direction opposite to the direction of the arrow mark in FIG. 2, it is sufficient to demagnetize the first solenoid 30 and energize the second solenoid 3/.

By configuring the operating bags M and 20 as described above, the movable table blade can be controlled with high accuracy by controlling the energization state of each solenoid in which direction the movable table sword is moved.

Note that the actuating device l is not shown in FIGS. 1 and 2.

In either case, the magnetic core 3. It goes without saying that it is preferable that the other members of the shield are made of non-magnetic material, such as brass.

Next, a typical experimental example of this invention will be shown.

<Experimental example> The actuating device shown in Fig. 1 was used. The length of the magnetic core is 105
The 111% diameter is 29.2 mi, and the tip end face of the magnetic core has a diameter of 15 m. Piston diameter is 2L9sm
, and the gap with the cylindrical fixed part is 0.2
5 sea. The inclination angle of the tapered surface is 9.5°. Moreover, the mass of the movable table is 132f. The solenoid has a triple coil in order to exert a large force, and the number of turns of each coil is 2020 and 1, respectively.
473, 1042, and each coil is connected in parallel to the power supply.

As the magnetic fluid, water-paced W-35 (trade name; manufactured by Taihohe Corporation), which has a low viscosity, was used.

The amount of displacement of the movable table was measured using a Michelson interferometer.

The magnetic flux density was measured using a magnetometer.

Figure 3 shows the relationship between the amount of current flowing through the solenoid and the magnetic flux density. As shown in FIG. 3, the current cover and magnetic flux density have a linear relationship, and a stable magnetic field can be obtained by the solenoid.

FIG. 4 shows the relationship between the amount of displacement of the movable table and the current value. As shown in FIG. 4, a large current value causes a large amount of displacement, and a small current change in a high current value range causes a large displacement of the movable table. Therefore, even if the speed at which the current is changed is the same, the moving speed of the movable table differs between the low current value range and the high current value range. Taking this into consideration, the amount of movement of the movable table per unit of time can be made approximately constant.

FIG. 5 shows the relationship between the amount of displacement of the movable table and time.

The average speed of current change is 0.00834/8, but as is clear from Figure 5, it is possible to move the movable table at a constant speed and achieve high positional accuracy. can.

Although this invention has been described above with reference to Examples, this invention is not limited to the above-mentioned Examples.
It goes without saying that the invention can be modified and implemented as appropriate within the scope of the gist of the invention.

According to this invention, the magnetic field generated by the excitation of the solenoid attracts the magnetic fluid into the inside of the cylindrical fixed part, and the piston-shaped movable part moves as the volume of the magnetic fluid inside the cylindrical fixed part increases. The longer the cylindrical fixed part is, the longer the displacement of the piston-like movable part can be realized.

In addition, by varying the amount of current applied to the solenoid, the amount of displacement of the cylindrical fixed part can be adjusted as desired, and the volume of the magnetic fluid drawn into the cylindrical fixed part can be finely adjusted. Because you can
The displacement of the piston-like movable part can be adjusted with high precision.

[Brief explanation of drawings]

FIG. 1 is a sectional view showing a first embodiment of the invention, FIG. 2 is a sectional view showing a second embodiment of the invention, and FIGS. 3 to 5 are sectional views of the first embodiment. Figure 3 shows the relationship between current value and magnetic flux density, Figure 4 shows the relationship between current value and displacement of the movable table, and Figure 5 shows the relationship between time and the displacement of the movable table. The relationship between the amount of displacement and the amount of displacement is shown. l...actuating device, λ...cylindrical fixing part, da...
... Solenoid, 7... Piston, lo... Magnetic fluid, Ko... Actuating device, -k... First cylindrical fixed part, n... Second cylindrical fixed part, 3o...・First solenoid, 31... Second solenoid, -q...
1st piston 1, CO... 2nd piston, 3II...
1st magnetic fluid, 35... 2nd magnetic fluid. Figure 5 Electrical shift 1 (A) Figure 5 Figure 4

Claims (1)

[Claims] A piston-shaped movable part is movably provided inside a cylindrical fixed part, magnetic fluid is attracted into the fixed part by a magnetic field generated by excitation of a solenoid, and movement of the piston-shaped movable part is controlled by attraction of the magnetic fluid. An actuating device using magnetic fluid, characterized by: