JPH0312053Y2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a support mechanism for a mover in a linear stepping motor comprising a stator and a mover disposed opposite to the stator.

As a conventional mover support mechanism for a linear stepping motor, a mechanism as shown in FIGS. 1 and 2 has been proposed. In the conventional example shown in FIGS. 1 and 2, V-shaped grooves 22, 22 are formed on both side edges of the upper surface of the stator 21, and an appropriate number of balls 23 are arranged in these grooves 22, 22, respectively. Each ball 23 is supported by a retainer 25 that is movable together with the balls 23 to prevent the balls 23 from moving inadvertently.
3 is kept constant.

According to the above-mentioned conventional example, the retainer 25 moves while keeping the distance between the balls 23 constant through the circular holding holes, so a contact portion is created between the balls and the retainer, causing friction, which causes the movement of the mover. There are problems in that the movement becomes uneven, causing an error in the step amount of the mover, and when the motor starts and stops, the ball is affected by the inertia of the retainer, causing the ball's position relative to the mover to shift, resulting in a step error. Ta.

The object of the present invention is to provide a mover mechanism for a linear stepping motor that has almost no contact between the balls and the retainer, and also prevents the balls from being affected by the inertia of the retainer, thereby improving stepping accuracy. Our goal is to provide the following.

A feature of the present invention is that the mover is supported by the stator via a rotating body, and a retainer is fixed to either the stator or the mover, and the retainer is provided with A rotary body holding hole having a length equal to or longer than the maximum movement range of the rotary body is formed, and the rotary body is disposed within the rotary body holding hole of the retainer.

The present invention will now be described with reference to the embodiments shown in FIGS. 3 and 4.

3 and 4, in a stator 1 of a linear stepping motor, a stacked stator core 2 and a coil 3 wound around the stator core 2 are housed in a pre-formed housing hole 4 and fixed with adhesive. has been done. Guide rails 5, 5 each having a V-shaped groove are embedded and fixed in both side edges of the upper surface of the stator 1 in FIG.
A mover 9 is disposed on the stator 1 so as to be opposed to the guide rails 5, 5 and has guide rails 8, 8 embedded and fixed therein. Slider pieces 6 and 7 are fixed to the lower surface side of the mover 9,
These slider pieces 6, 7 are attached to the stator core 2.
is facing. The mover 9 has an appropriate number of rotating bodies interposed between the V-shaped grooves formed in the guide rails 8, 8 and the cross-shaped grooves formed in the guide rails 5, 5 on the stator 1 side. By being supported via the balls 10, smooth step movement relative to the stator 1 is possible. The reason why the V-shaped grooves are formed in the guide rails 5, 5 is to prevent the mover 9 from shifting laterally due to shocks, etc., and even if it is not a V-shaped groove,
For example, it may be a semicircular groove. A suitable interval is formed between the slider pieces 6 and 7 of the mover 9 and the core 2 of the stator 1, and a permanent magnet 19 is fixed between the slider pieces 6 and 7 of the mover 9. The balls 10 are held from both the top and bottom by the holding holes 11a and 12a of the retainers 11 and 12, which are fixed to the mover 9 and stator 1 by press-fitting pins 13 and 14 into the mover 9 and stator 1, respectively. . Each retainer 11, 12
The ball holding holes 11a and 12a are formed one for each ball 10, and the ball holding holes 11a and 12a are formed one for each ball 10.
The ball 10 is held within these ball holding holes 11a and 12a. Therefore, when the mover 9 moves in steps, the balls 10 can rotate smoothly without contacting the ball holding holes 11a, 12a of the retainers 11, 12. FIG. 3 shows the case where the mover 9 has moved the maximum distance upward in the figure, and in this state, the stator is moved so that the balls 10 do not come into contact with the edges of the ball holding holes 11a and 12a of the retainers 11 and 12. 1, and unless slippage occurs between the mover 9 and the ball 10 due to a strong shock, the ball 10 will move to the retainer 11, no matter where the mover 9 moves. The mover 9 can be moved smoothly without contacting the mover 12. Furthermore, since the retainers 11 and 12 are both fixed to the mover 9 or the stator 1 and do not move together with the balls 10, the inertia of the retainers 11 and 12 will not have a negative effect on the step movement of the mover 9. .

Fixing parts 1a, 1a are integrally provided on both side surfaces of the stator 1, and fixing members 15, 16 are provided using the lower and side surfaces of the fixing parts 1a, 1a as reference surfaces.
The linear stepping motor according to the above embodiment can be attached to a machine frame or the like by pressing it against a reference surface of the machine frame or the like. The fixing members 15 and 16 are fixed to the machine frame by screws 17 and 17.

In addition, in the above embodiment, the stator 1 and the mover 9
A retainer is provided on both sides of the ball to prevent the ball from flying out if the mover moves too far for some reason when the motor is not used in a horizontal position. Therefore, when the motor is used only in a horizontal state, the retainer only needs to be provided on either the stator side or the mover side. In addition, in the illustrated embodiment, the rotating body for supporting the mover is a ball, but instead of the ball, a cylindrical or abacus spherical roller may be used, and the guide rail can be adjusted depending on the shape of the roller. It is only necessary to determine the shape of the groove.

According to the present invention, the retainer is fixed to the stator or mover, and the length of the rotating body holding hole formed in the retainer is made longer than the maximum movement range of the rotating body, so there is no contact between the retainer and the balls, and the retainer It is possible to prevent stepping errors of the mover caused by contact with the ball, and it is also possible to prevent positional deviation of the ball and stepping errors due to the inertia of the retainer when the motor is started and stopped.

[Brief explanation of the drawing]

FIG. 1 is an exploded perspective view showing an example of a conventional linear stepping motor, FIG. 2 is an exploded perspective view of the same as above, FIG. 3 is a plan view showing an embodiment of the present invention, and FIG. - It is a sectional view along the A line. 1... Stator, 2... Stator core, 5...
Guide rail, 8... Guide rail, 9... Mover, 10... Ball as a rotating body, 11... Retainer, 12... Retainer, 11a... Rotating body holding hole, 12a... Rotating body holding hole.

Claims (1)

[Claims for Utility Model Registration] A linear stepping motor comprising a stator, a mover supported by the stator so as to be able to reciprocate via a plurality of rotating bodies, and a retainer that prevents blind movement of the rotating bodies, A retainer is fixed to each of the stator and mover, and each retainer is formed with a plurality of rotating body holding holes each having a length that is at least the maximum movement range of the rotating body that accompanies the reciprocating movement of the mover, and each of the rotating body holding holes A mover support mechanism for a linear stepping motor, characterized in that each of the movers holds one rotating body.