JPH0419987Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to the shape of a slit plate as a component of a secondary scale of a linear pulse motor.

Normally, a linear pulse motor is equipped with a plurality of magnetic poles in the primary side magnetic flux generation part, and each magnetic pole has teeth of the same pitch as the secondary side scale, and each magnetic pole is 1/P when the number of magnetic poles is P. 1/P with a phase shift of
It is configured to move step by step (continuously when viewed visually).

By the way, the configuration of the linear pulse motor secondary scale is disclosed in FIG. 1 and FIG. 2, which shows a cross section taken along the line AA in FIG. 1. That is, in each figure, reference numeral 1 denotes a substrate made of a magnetic material, which has sufficient strength not to be deformed by external stress. Reference numeral 2 denotes a slit plate for forming teeth, in which teeth 2a are formed with slits 2b at the same pitch as the teeth formed on the primary magnetic pole (not shown) by punching or so-called etching based on chemical corrosion. . Then, the substrate 1 and the thin iron plate 2 are bonded together to obtain a linear pulse motor secondary scale.

In the conventional linear pulse motor scale described above, it is necessary to make the cap with the magnetic pole surface (not shown) as small as possible to increase the magnetic attraction between the primary and secondary, and to increase the thrust. For this purpose, it is required to increase the width and shorten the length of the tooth portion 2a.

On the other hand, in a linear pulse motor, the length of the scale tooth portion 2a is large in order to obtain the necessary thrust, and the length of the tooth portion 2a is made small in order to obtain smooth operation and increase the resolution. In recent years, smaller widths have been increasingly required in various applications.

However, when the length of the scale tooth portion 2a is increased and the width is decreased, the iron plate 2 for forming the scale tooth portion is originally thin and the width of the tooth portion 2a is also very thin. The scale as a finished product obtained by bonding the tooth forming iron plate 2 to the substrate 1, which is sufficiently thick compared to the slit plate 2, is often deformed in the tooth portion 2a during the manufacturing process, and the characteristics of the linear pulse motor are affected. Non-uniformity occurred in the pitch dimension of the upper tooth portion 2a, which affected the fluctuation of the thrust of the motor in each excitation mode, that is, the interphase variation of the thrust. Furthermore, the non-uniformity of the tooth pitch also has the disadvantage of impairing the precision with which the motor stops.

For this reason, it has been considered to provide one or more pillars in a direction perpendicular to the longitudinal direction of the scale teeth obtained by forming the slits. Therefore, there were many negative aspects in terms of efficiency, and there were problems in practical use.

The purpose of the present invention is to half-etch the support portions of the slit plate, which are located perpendicular to the longitudinal direction of the teeth obtained by forming the slits based on etching, compared to the complete etching of the slit portions, and to The objective is to increase the strength of the teeth without reducing efficiency.

The illustrated embodiment will be specifically described below. FIG. 3 is a plan view of the scale according to the present invention, and FIG. 4 is a sectional view taken along line BB in FIG. 3. In each figure,
A substrate 1' is made of a magnetic material and has sufficient strength to prevent deformation against expected external stress. Reference numeral 2' denotes an iron plate for forming tooth portions, and tooth portions 2a' are formed by etching.

Incidentally, each slit 2b' for forming the toothed portion 2a' is divided into two by a post 2c' formed midway, and the length of this slit 2b' is set in half. This support post 2c' is formed by half-etching, and has a smaller thickness than the tooth portion formed by etching.

In the above configuration, the presence of the support column 2c' is due to the presence of the toothed portion 2c'.
The length of the slit 2b' for forming a' is reduced to substantially 1/2. Therefore, the strength of the teeth 2a' sandwiched between the slits 2b' is increased. Moreover, since the support column 2c' is formed by half-etching, it strongly suppresses magnetic circuit loss when thrust is generated by the linear pulse motor.

As described above, the slit plate for forming the scale side teeth for a linear pulse motor according to the present invention has one or more locations in the longitudinal direction of the teeth obtained by the slits at right angles to the longitudinal direction of the teeth. One or more pillars extending in the direction are formed by half-etching. Based on this configuration, not only can the strength of the tooth portion be obtained by the support, but since this support is formed by half-etching, the reduction in operating efficiency of the linear pulse motor can be avoided by forming the support to the same thickness as the tooth portion. It can be made significantly smaller than in the case of

[Brief explanation of drawings]

Figures 1 and 2 are a plan view and a sectional view taken along the line A-A, respectively, showing the scale of a conventional linear pulse motor, and Figures 3 and 4 are a plan view and a sectional view taken along the line B-B, respectively, of the scale of the present invention. be. 2'...Slit plate, 2a'...Tooth section, 2b'...
Slit, 2c'...post.

Claims (1)

[Scope of utility model registration request] A slit forming the tooth portion is formed by etching, and one or more struts extending perpendicularly to the longitudinal direction of the tooth portion are formed by half-etching in the middle of the tooth portion in the longitudinal direction. Slit plate for linear pulse motor.