JPS61293154A - Brake mechanism for linear pulse motor - Google Patents

Abstract

PURPOSE:To reduce the quantity of generated heat with power-saving, by shifting the position of a working member to the first or the second stable point with pulse-form exciting current. CONSTITUTION:When positive directional pulse-form current is fed to a coil 52, then magnet yokes 54a, 54b are rotatably moved clockwise and are moved to the first stable point, and the rubber member 56a of a brake section 56 is butted to the side face 1b of a mover 1, and the brake is applied to the mover 1. In the meantime, when counter directional pulse-form current is fed to the coil 52, then the magnet yokes 54a, 54b are rotatably moved counter-clockwise and are moved to the second stable point, and the rubber member 56a is separated from the side face 1b of the mover 1, and the brake is release. After pulse-form current disappears, the position after the movement is retained by the action of permanent magnets 53a, 53b, and so the coil 52 may be excited only at the time of movement, and power consumption and generated heat quantity can be reduced.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a linear pulse motor suitable for use in moving the head of a floppy disk device, etc. The present invention relates to a brake mechanism for a linear pulse motor that is capable of maintaining the position of a moving element even when the vehicle is overloaded with force.

[Background Art] In recent years, office automation (OA) has become popular, and floppy disk devices are widely used as storage devices. Linear pulse motors are often used to drive the heads of these floppy disk devices, and there is a strong demand for smaller, cheaper, and thinner motors. Therefore, the present applicant previously proposed a linear pulse motor that achieves the above requirements in Japanese Patent Application No. 59-47863.

4 and 5 are perspective views showing an example of the configuration of a linear pulse motor of the same type as the linear pulse motor according to the above proposal. In these figures, 1 is a mover made of mild steel or the like, 2 is a stator, and the lower surface of this mover 1 is formed with comb-shaped mover teeth 1a.

On the other hand, the stator 2 sequentially moves the slider teeth 1a by sequentially switching magnetic poles with increasing magnetic flux through interaction between the permanent magnet 3 and the electromagnet, thereby reciprocating the slider l in a stepwise manner. It consists of the following composition.

First, a slit plate 4 is arranged on the lower side of the mover 1 and facing it, and on the lower side of the slit plate 4 there is a yoke 6 to which a coil 5.5 for an electromagnet is fixed, and a yoke 6 that is H-shaped in plan view. Permanent magnets 3 having shapes are fixed in sequence.

A cross-shaped groove is formed in the center of the yoke 6, thereby forming four magnetic poles 6a', 6b, 6c, and 6d. In addition, magnetic poles 6 a, 6 b, 6 c,
At a position on the slit plate 4 directly above the comb-shaped pole teeth 4a, 4.6d. b, 4 c, and 4 d are formed and face the moving child tooth 1a of the moving child 1 with an extremely small gap therebetween.

This gap is formed by a pair of linear bearings 7.7 arranged on both sides of the slit plate 4. The slider 1 is placed on the linear bearing 7, and the linear bearing 7 and the slider l and the slit plate 4 and the guide 8.
It is fitted into the running path formed by 9 so as to be movable in the longitudinal direction.

FIG. 6 is a perspective view showing the configuration of the linear bearing 7. As shown in the figure, the linear bearing 7 consists of a pair of rollers II, II, balls 12, 12, and a retainer 13 that holds these.
is in the opening 14.14, the ball 12.12 is in the recess 15,
15, each of which is rotatably fitted. In addition,
In FIG. 4, 16 is a stopper that is bent upward to restrict movement of the linear bearing 7, and 18 is a back plate that constitutes the magnetic path of the permanent magnet 3.

According to the second configuration, both sides of the lower surface of the moving element 1 abut against the rollers 11, 11 of the linear bearing 7, and both side edges of the moving element 1 abut against the balls 12, 12. Then, the movable tooth 1a and the pole tooth 4. a, 4b, 4c.

4d face each other with a slight gap. In this state, when a predetermined pulsed current is supplied to the coil 5.5, the mover 1 moves on the stator 2 in a stepwise manner.

The above-mentioned linear pulse motor is extremely superior in that it can be constructed in a compact, low-cost, and thin design, but when it is used to drive the head of a floppy disk device, there are the following problems.

In other words, a floppy disk device, especially a floppy disk device that uses a battery as a power source, is configured so that current is supplied to the linear pulse motor only when driving the head (seek time), so that no unnecessary current flows. It is hoped that However, as mentioned above, when no current is supplied to the near-pulse motor, the force that holds the mover 1 in a fixed position is weak, so a slight impact may cause the head to shift its position, and the subsequent head drive operation may be affected. There was a problem that the process could no longer be performed normally.

For this reason, in the past, one of the guides 8 or 9 was provided with a brake mechanism as shown in FIG. 7, and the brake was applied to the mover l (brake) at all times except for seek 4.

In FIG. 7, 21 is a yoke, and this yoke 21
A coil 22 is wound around the coil 22 . Furthermore, one end of the moving section 23 is rotatably attached to one end of the yoke 21 . A protrusion 23a facing the other end 21a of the yoke 21 is formed at the other end of the moving part 23, and a spring 24 whose one end abuts the other end 21a is fitted into the protrusion 23a. ing. As a result, the moving part 23
When the coil 22 is not energized, the brake section 25 provided in the center of is biased toward the mover ■ by the spring 24 and applies a brake to the mover ■, while when the coil 22 is energized, The protruding portion 23a is attracted to the other end portion 21a of the yoke 21, and the brake portion 25 is separated from the mover l, so that the brake is released.

[Problems to be Solved by the Invention] By the way, in the above-mentioned conventional brake mechanism, the coil 22 must be energized all the time while the brake is released (that is, during shearing), so the electric power is It consumes a lot of heat and generates a lot of heat, making it difficult to use it in devices that dislike heat, such as floppy disk devices.

The present invention was made against this background, and an object of the present invention is to provide a brake mechanism for a linear pulse motor that consumes less power and generates less heat.

[Means for Solving the Problems] In order to solve the above problems, the present invention provides an actuator that has a permanent magnet and is movable between a first stable point and a second stable point. a member, and driving the actuating member to cause the first
, comprising an electromagnet that moves between the second stable points and a brake section that applies a brake to the mover when the actuating member is at the first stable point, and the electromagnet is excited in the positive direction. When the actuating member is moved to the first stable point, and the actuating member is held at the first stable point even after this excitation is finished, and when the electromagnet is energized in the opposite direction, the actuating member is moved to the first stable point. The actuating member is moved to a second stable point, and the actuating member is maintained at the second stable point even after the reverse excitation of the bracket is completed.

[Function] According to the above configuration, the position of the actuating member can be moved to the first or second stable point by the pulsed excitation current, and the moved actuating member remains at that position.
Therefore, there is no need to keep the excitation current flowing through the coil. As a result, when the linear pulse motor having the brake mechanism is used to drive a head of a floppy disk device or the like, it becomes possible to save power and reduce the amount of heat generated.

[Example] Hereinafter, the present invention will be described in detail with reference to the drawings.

FIG. 1 is a perspective view showing the structure of a first embodiment of the present invention. In this figure, a pair of spacers 31 and 32 are arranged in the central part of the upper surface of the guide 8 in the longitudinal direction, and on the upper surface of the spacer 31 there is a yoke 33 having a roughly U-shaped planar shape.
On the other hand, a moving part 34 is screwed to the upper surface of the spacer 32 so as to be slidable in the width direction of the guide 8.

A coil 35 is wound around the yoke 33.
is excited, the opposite ends 33a of the yoke 33,
A magnetic field is formed between 33b and 33b. A magnet yoke 36a that moves together with the moving part 34 is disposed between both ends 33a and 33b, and a magnet yoke 36a that is parallel to this magnet yoke 36a is arranged between the two end parts 33a and 33b.
b is fixed via a permanent magnet 37, and these magnetic yokes 36a and 36b sandwich the end 33a of the yoke 33. In this way, both ends 33a, 3
3b and the magnet yokes 36a, 36b are arranged in the order of 33b, 3'6a, 33a, and 36b from the inside, and interact with each other due to magnetic force.

Further, a brake portion 38 is formed on the side surface of the moving portion 34 and projects toward the side surface lb of the mover 1, and a rubber member 38a is fixed to the tip thereof.

In addition, in the figure, 39 is a regulating member that regulates the movement of the brake part 38.

In such a configuration, when a pulsed current in the positive direction is supplied to the coil 35, both ends 33a, 3 of the yoke 33
3b, a magnetic field is generated for a short period of time, and the magnetic yoke 36b is attracted to the end 33a of the yoke 33, and the magnetic yoke 36a is attracted to the end 33b. Therefore, the moving part 34 and the brake part 38 are
The rubber member 38a moves in the direction of the side surface 1b of the slider l.
comes into contact with. Even after the above-mentioned current supply ends, the magnetic yokes 36b and 36a are attracted to the ends 33a and 33b by the action of the permanent magnet 37, so that
The moving part 34 and the brake part 38 hold the device (first stable point) to this extent, and the brake is maintained in the applied state.

On the other hand, when a pulsed current in the opposite direction is supplied to the coil 35, a magnetic field in the upper and opposite directions is generated for a short period of time between the ends 33a and 33b of the yoke 33, and the magnetic yoke 36a is attracted to the end 33a. Therefore, the moving part 34 and the brake part 38 move outward (to the left in the figure), and the rubber member 38 moves outward (leftward in the figure).
a separates from the side surface lb of the mover 1, and the brake is released. Even after the above-mentioned current supply is finished, the magnetic yoke 36a continues to operate at the end 33 due to the action of the permanent magnet 37.
Since the moving part 34 and the brake part 38 are held at this position (second stable point), the brake remains disengaged.

Next, FIG. 2 is a plan view showing the configuration of a second embodiment of the present invention. In this figure, 41 is an E-shaped yoke in plan view, and a central protrusion 41a of the yoke 41 has a coil 4.
2 is wound. When the coil 42 is excited, a magnetic field is formed between the protrusions 41b and 41c on both sides of the yoke 41 and the central protrusion 41a.

Three magnet yokes 43a, 43b, 43c that move integrally in the left-right direction in the figure are disposed on one end side of the protruding parts 4 lb, 41a, 41c of the yoke 41, and each tip thereof is attached to the protruding part 4 lb. , 41a, 41c at two different positions. That is, the magnet yoke 43a.

The tips of 43b and 43c are protrusions 4 l b and 41 a
, 4.1c, and the magnetic yokes 43b, 43c are in contact with the protrusion 4.1c. lb and a second stable point that abuts on 41 a. Moreover, permanent magnets 44a, 44. b is interposed, and the magnetic yoke 43
a.

A moving part 45 is fixed to surround one end of permanent magnets 4.3b, 4.3c and permanent magnets 44a, 44b. This moving part 4
5 is slidably attached to a slide pin 46° 46 fixed to the guide 8, and a brake portion 4 extending toward the side surface 1b of the slider 1 is provided on one side of the moving portion 45.
7 is formed, and a rubber member 47a is fixed to the tip thereof.

In such a configuration, when a pulsed current is supplied to the coil 42, the moving part 45 moves to the first stable point (brake position) or the second stable point, in the same way as described in the first embodiment. Stops at a stable point (brake release position).

That is, when a pulsed current in the positive direction is supplied to the coil 42, the magnetic yokes 43a, 43b, 43c are attracted to the protrusions 4lb, 41a, 41c, respectively, and the brake part 47 moves in the direction of the slider 1. Rubber member 47a
comes into contact with the side surface of the mover 1 and reaches the brake position, and conversely, when a pulsed current in the opposite direction is supplied to the coil 42,
The magnetic yoke 43c is attracted to the protruding portion 4.1a, and the magnetic yoke 43b is attracted to the protruding portion 41b, resulting in the brake release position. Even after the supply of the pulsed current is stopped, the moving part 45 is held at the moved position by the action of the permanent magnets 44a and 44b.

Finally, FIG. 3 is a plan view showing the configuration of a third embodiment of the present invention. In the figure, 51 is a yoke that is approximately C-shaped in plan view, and a coil 52 is wound around this yoke 51. Further, a permanent magnet 53a is provided between both ends 51a and 51b of the yoke 51.

Magnet yoke 54 fixed parallel to both sides of 53b
a, 54b are arranged and horizontally rotated between two stable points around a shaft 55 inserted into the center of the permanent magnets 53'a, 53b. That is, as shown in the figure, there is a first stable point where one end of the magnet yoke 54a abuts the one end 51a of the yoke 51, and the other end of the magnet yoke 54b abuts the other end 51b of the yoke 51, and the magnet The other end of the yoke 54a contacts the other end 51b of the yoke 51, and one end of the magnet yoke 54b contacts the one end 5 of the yoke 51.
The magnetic yokes 54a and 54b rotate between the second stable point that contacts 1a. The brake part 56 fixed to the magnetic yoke 54b also rotates between these two stable points, and when it is at the first stable point, the rubber member 56 attached to the tip of the brake part 56 rotates.
A is configured to abut against the side surfaces t and b of the mover 1 and apply a brake thereto.

In such a configuration, when a pulsed current in the positive direction is supplied to the coil 52, the magnetic yokes 54a, 54
b rotates clockwise and moves to the first stable point, and the rubber member 56a of the brake part 56 comes into contact with the side surface 1b of the slider l and applies a brake thereto, while the coil 52 is rotated in the opposite direction. When a pulsed current of Remove the brake. At each of the above-mentioned stable points, even if the supply of the pulsed current ends, the magnetic yoke 54 is
a, 54. b and the brake section 56 maintain their positions.

In each of the above embodiments, the brake is applied to the side surface 1b of the mover 1, but the brake mechanism may be mounted vertically and the brake applied to the upper surface of the mover 1.

Furthermore, a brake mechanism may be provided at a suitable location in the lower part of the mover 1, for example, in a space at both ends of the stator in the direction of movement of the mover 1, and brakes may be applied to the lower tooth portion 1a of the mover 1.

[Effects of the Invention] As explained above, in the present invention, the brake part moves between two stable points by the pulsed current, and after the pulsed current is no longer supplied, the brake part moves by the action of the permanent magnet. Since the previous position is maintained, the coil only needs to be energized when moving, reducing power consumption and heat generation. In particular, when a linear pulse motor with this brake mechanism is used in a floppy disk device, etc., once the brake is applied, this state is maintained even after the current is turned off, so there is no risk of the mover moving due to impact. Therefore, there is no need to supply current to the linear pulse motor except during seek, and it is possible to reduce power consumption and heat generation.

[Brief explanation of the drawing]

1 to 3 show first to third embodiments of this invention.
FIG. 1 is a perspective view, FIGS. 2 and 3 are plan views, and FIG. 4 is an exploded perspective view showing the configuration of a conventional linear pulse motor. , FIG. 5 is a perspective view showing the external configuration of the linear pulse motor, FIG. 6 is a perspective view showing the configuration of the linear bearing of the linear pulse motor, and FIG. 7 is a perspective view showing the configuration of a conventional brake mechanism. be. 1...Mover, 8.9...Guide (guiding member), 33.41.51...Yoke (electromagnet), 34,45°...・Moving part (operating member),
35, 42.52... Coil (electromagnet), 36
a, 36b, 43a, 43b, 43c, 54a, 54b
...Magnet yoke (operating member), 37.4
4a, 44b, 53a, 53b...---Permanent magnet (
actuating member), 38, 47.56...brake part. =16- Figure 7

Claims (1)

[Claims] A linear pulse motor having a guide member and a mover that travels on a traveling path formed by the guide member, which has a permanent magnet and is movable between a first stable point and a second stable point. an electromagnet for driving the actuating member to move between the first and second stable points, and applying a brake to the mover when the actuating member is at the first stable point. and a brake section for moving the actuating member to the first stable point when the electromagnet is excited in the positive direction, and for moving the actuating member to the first stable point even after this excitation ends.
The actuating member is held at a stable point, and when the electromagnet is excited in the opposite direction, the actuating member is moved to a second stable point, and even after this reverse excitation is finished, the actuating member is held at the second stable point. A brake mechanism for a linear pulse motor, characterized in that the actuating member is held in the brake mechanism.