JPS5812527B2 - Keishia Seigiyosouchi - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention is a modification of the so-called Pois coil type linear motor device, and relates to a device that controls not one-dimensional positional changes but changes in tilt angle (three-dimensional).

There are many requests for tilt attitude control in optical instruments, and there are also many cases where precision measuring instruments are required to be kept horizontal at all times.

In the past, efforts have been made to statically adjust this and maintain it statically, using anti-vibration tables and the like to isolate external vibrations.

However, in recent years, as the performance of servo control elements has improved, a concept has emerged in which the speed of response is utilized to control the attitude by feeding back the output of the transducer that measures the attitude.

The present invention is a servo motor for tilt posture control using such servo control.

As a servo motor, a moving coil motor with low inductance and excellent linearity of current and generated force, also known as a voice coil motor based on the dynamic speaker principle (Fig. 1), is said to be suitable.

The present invention is a modification of this voice coil motor, and as shown in Fig. 2, a plurality of divided coils are fixed to a winding frame so as to be suitable for tilt attitude control, and each coil is divided into two parts, each of which has a function calculated according to the desired tilt direction. By passing a current through the spring, the winding frame supported by a spring is given an arbitrary inclination.

That is, three-dimensional detection is made possible by providing divided coils on the side surfaces of the winding frame.

As a control method, for example, as shown in Fig. 2, a simple method is to place transducers at three locations and control each moving coil as a motor, but there is also mutual interference, and these It is also possible to control the current of each coil by predicting it by a computer.

The support spring may be replaced by a spherical bearing. The present invention will be explained in detail below with reference to the drawings.

Figure 1 shows only the voice coil section of a normal dynamic speaker with the cone section removed. 1 is the voice coil, 2 is its supporting spring, which supports the voice coil in the magnetic pole gap, and the vertical direction in the figure. The magnetic poles 3 and 4 are prevented from touching the magnetic poles 3 and 4 because there is no degree of freedom in other directions.

5 is a permanent magnet, the magnetic flux of which reaches the magnetic pole 4 from the magnetic pole 3 through the magnetic pole gap.

6 is a yoke. The figure shows the yoke and voice coil partially cut out to explain the inside.

FIG. 2 shows an embodiment of the present invention, in which 7 is a moving coil and 7
The part a is in the magnetic pole, and the part 7b is in a weak magnetic field and generates almost no force.

8 is a cylindrical winding frame.

That is, the coil 7 is provided on the side surface of the cylindrical winding frame 8 so that the magnetic flux interlinking with this coil does not coincide with the central axis of the cylindrical winding frame 8. Although not clearly shown in the figure, such a coil 7 are arranged on each side of the cylindrical winding frame 8 having a triangular cross section.

10 is a permanent magnet, which forms a magnetic pole gap between magnetic poles 11 and 12, and provides interlinkage magnetic flux to the coil.

13 is a yoke. The support spring 9 supports each vertex of the winding frame 8 with the magnetic pole 12 as a fixed end, and allows the winding frame 8 to have a degree of freedom only in the vertical direction as shown in the figure, so that the movable coil 7 and the winding frame do not touch the magnetic pole. It supports me like this.

Reference numeral 14 denotes a strain gauge attached to the support spring, which is used as a transducer to convert displacement into an electrical quantity.

That is, it receives signals from transducers 14 placed at three locations, converts them into voice coil motor current, and supplies the current to the voice coil.

With this structure, if the current flowing through each coil 7 is servo-controlled so that the output of each transducer 14 becomes a predetermined value, in other words, each coil can be controlled so that it generates a different tilting moment. For example, the winding frame 8 can be maintained at a constant inclination angle.

As described above, the present invention provides a plurality of divided coils on the side surface of a cylindrical winding frame having a circular or polygonal cross section, so that the magnetic flux interlinking with the coils is aligned in the central axis direction of the cylindrical winding frame. a plurality of transducers for converting the positional displacement of each coil into an electric quantity; The present invention is characterized in that each of the coils is configured to generate a predetermined inclination moment by a control means for controlling the current flowing through the coil, and the inclination angle of the cylindrical winding frame is three-dimensionally controlled. Suitable for measuring equipment and controlling the posture of processed materials.

If a linear motor type as shown in Fig. 1 is used, it is not possible to perform arbitrary posture control without using at least three linear motors, but according to the present invention, there is an advantage that only one motor is required. In semiconductor manufacturing, which requires precise control, the gap between mask wafers can be uniformly controlled to a desired value, and by using multiple coils, the structure is simple and rigid, and the direction of gravity can be controlled. It has the effect of being variable and freely controllable to a certain extent.

[Brief explanation of drawings]

FIG. 1 is a principle diagram of a voice coil type linear motor, and FIG. 2 is an embodiment of the present invention. In FIG. 2, 7 is a moving coil, 8 is a cylindrical winding frame, 9 is a support spring, 10 is a permanent magnet, 11 and 12 are magnetic poles, 13 is a yoke, and 14 is a strain gauge as a transducer.

Claims (1)

[Claims] 1 A plurality of divided coils are placed on the side surface of a cylindrical winding frame having a circular or polygonal cross section at predetermined intervals so that the magnetic flux interlinking with the coils does not coincide with the central axis direction of the cylindrical winding frame. a plurality of transducers that convert the positional displacement of each coil into an electrical quantity, and a current flowing through each coil according to the output of the plurality of transducers. An inclination control device characterized in that the coils are configured to generate a predetermined inclination moment by a control means, and the inclination angle of the cylindrical winding frame is three-dimensionally controlled.