JPS63206153A - Linear pulse motor - Google Patents

Abstract

PURPOSE:To generate a large locking force at the time of interrupting a power source while the power consumption of a plunger coil is suppressed by using a plunger engaged with the tooth slot of a secondary side magnetic circuit. CONSTITUTION:A movable element 11 is formed by attaching a permanent magnet to a magnetic path in which a bias magnetic flux flows in one direction, thus coupling an electromagnet comprising exciting coil 2-1 wound the permanent magnet. In the element 11, a plunger 18 is disposed perpendicularly through attaching fittings 19 to one end face arranged with rollers at both edges with teeth of a predetermined pitch on the face opposed to a stator 5 so that a locking member 18-4 secured to the end of a plunger shaft 18-2 is opposed to the stator teeth 5a of the stator 5. A locking member 18-4 is engaged with a connecting member by the tension of a recoiling spring 18-3 at the time of interrupting a power source to lock the element 11.

Description

[Detailed Description of the Invention] [Summary] A permanent magnet and an electromagnet are combined in a magnetic path through which bias magnetic flux flows, forming teeth with a constant pinch on the end face, and rollers that rotate and advance on a stator are attached to both ends. In addition to the conventional structure, a plunger drive circuit consisting of a plunger, which has a plunger on one end face with a locking member fixed to the tip of a plunger shaft driven by a plunger coil, and an electromagnet, is added to the conventional structure. By configuring the excitation circuit with a circuit connected in series with the excitation circuit, locking can be achieved when the power is turned off.

[Industrial application field]

The present invention relates to a linear pulse motor.

Linear pulse motors can be driven in an open-loop manner by directly connecting a load without using a rotary-linear conversion structure, allowing for a reduction in the number of parts and miniaturization. Drive head feed, etc.

Used in OAi equipment.

In such applications, power saving such as battery drive is progressing, and it is desirable to cut off the drive power when stopping after positioning operation (hereinafter referred to as "power cut off"). There is a need for a linear pulse motor that has the ability to generate

[Conventional technology]

Traditionally, the widely used linear pulse motor is
As shown in the front view of Figure fa), the magnetic circuit on the primary side, that is, the mover 1, has two permanent magnets 1-1 attached to it so that the bias magnetic flux flows in one direction. Two electromagnets 2 each having an excitation coil 2-1 wound around the permanent magnet 1-1 are combined to provide magnetic poles 2a, 2b, 2c, and 2d, and the magnetic poles 2a, 2b, 2c, and 2d are The secondary magnetic circuit, that is, the surface facing the stator 5, has teeth with a constant pitch, and the teeth of the magnetic poles 2b, 2c, and 2d have teeth of 1/4 of the tooth pitch, respectively, with respect to the teeth of the magnetic pole 2a. ．． Rollers 3-1 are formed at right angles to the magnetic path 1-2 with a phase difference of 2/4.3/4 and are moved at a constant interval from the stator 1, at both ends thereof.

As shown in the side view of FIG. 4(b), the method of locking the movable element 1 includes a rotatable roller 4-2 fitted to the shaft 4-1 and a sliding body fixed to the leaf spring 4-3. Two pairs of rollers 4-4 are disposed on the movable element 1, and the rollers 4-2 and sliding bodies 4-4 are pressed against both sides of the stator 5 and held therebetween.

On the other hand, the magnetic circuit on the secondary side, that is, the stator 5, is
As shown in al, the stator teeth 5a have the same pinch as the magnetic pole teeth.

Further, the drive circuit for the movable element 1 includes a transistor 6 that performs a switching operation, and an excitation coil 2-1, as shown in FIG. An excitation circuit composed of a diode 7 and a surge absorbing diode 7 is connected in parallel to the power supply 10.

[Problem that the invention seeks to solve]

The problem with the conventional linear pulse motor described above is that the sliding body is pressed against the side of the stator by a leaf spring to prevent the mover from moving due to vibrations etc. when the power is turned off. When advancing, friction between the sliding body and the stator generates frictional resistance in the opposite direction to the advancing direction.

Therefore, in order to maintain the high positioning accuracy that is a feature of linear pulse motors, a large driving force is required to overcome the frictional resistance and perform positioning operations, and increasing the driving force requires an increase in the driving current. It is.

Therefore, it is difficult to reduce driving power in applications that frequently start and stop, such as printers and floppy disk drives.

SUMMARY OF THE INVENTION In view of the above-mentioned circumstances, it is an object of the present invention to provide a linear pulse motor in which the movable element can be locked easily and inexpensively when the power is turned off.

[Means for solving problems]

The above problem is solved by attaching two permanent magnets so that the bias magnetic flux flows in one direction, and attaching an electromagnet around the excitation coil 2-1 to the permanent magnets, as shown in Fig. 1(a). Plunger coil 18-1 and biasing member 18-3. That is, a moving body 18-2 driven by a return spring. That is, the plunger 18, which has a locking member 18-4 molded in a shape that can be locked to the locking member 5a of the stator 5 + the stator teeth, is fixed to the tip of the plunger shaft, and the plunger 18 is advanced through the fitting 19. A movable element 11 arranged perpendicular to the direction, (as shown in figure b1, a transistor 6, an excitation coil 2
-1. A conventional circuit consisting of a plunger coil 18-1 and a surge absorbing diode 17, and a plunger drive circuit consisting of a plunger coil 18-1 and a surge absorbing diode 17 are connected to a power source 1.
This problem is solved by the linear pulse motor of the present invention, which is combined with a circuit connected in series with 0.

It will be done.

[Effect]

That is, in the present invention, the magnetic attraction force per unit power consumption light of the exciting coil 2-1 is about 10 times greater than the stepping thrust;
Since the plunger coil 18-1 generates a large attractive force even with low power consumption, the force of the return spring 18-3 can also be increased, so when the excitation coil 2-1 is energized and the plunger coil 18-1 is energized to advance. 1 is also energized and the plunger shaft 18-2 is attracted into the plunger coil 18-1,
The locking member 18-4 fixed to the tip becomes separated from the locking member and loses its locking function, and when the power is turned off, the locking member 18-4 engages with the locking member by the force of the return spring 18-3, thereby locking the mover. becomes possible.

〔Example〕

An embodiment of the present invention will be described below with reference to FIGS. 1 to 3.

Fig. 1 shows the structure and circuit diagram of the linear pulse motor according to this embodiment. In the figure, the same members as in Fig. 5 are given the same symbols, and the other 18 lock the movable element. The plunger 19 is a fitting for the plunger.

The plunger 18 is a commercially available plunger that has a cylindrical plunger coil 18-1 with a return spring 18-3 inside it and attracts the plunger shaft 18-2 by excitation, as shown in Fig. 81, and two trapezoid teeth. A locking member 1 having a locking surface formed with
8-4 is fixed to the tip of the plunger shaft 18-2.

The attachment fitting 19 is a metal fitting made of a thin sheet metal formed into an L shape, and has holes for fixing the plunger 18 and attaching it to the movable element 11.

The movable element 11 using the above-mentioned member has a permanent magnet attached to a magnetic path through which bias magnetic flux flows in one direction, and an electromagnet having an excitation coil 2-1 wound around the permanent magnet is coupled to the stator 5. A locking member 18-4 fixed to the tip of the plunger shaft 18-2 is attached to one end surface of the stator 5, which has the same structure as the conventional one in which teeth are formed at a constant pitch on the opposing surfaces and rollers are arranged on both edges. A plunger 18 is vertically disposed via the fitting 19 so as to face the stator teeth 5a.

As shown in FIG. 1(b), a transistor 6 that performs a switching operation, an exciting coil 2-1. and a surge absorbing diode 7, and a plunger 18 drive circuit consisting of a plunger coil 18-1 and a surge absorbing diode 17, connected in series to the power supply 10. By constructing a circuit in the movable element 11, the movable element can be locked when the power is turned off.

As shown in FIGS. 2A and 2B, the lock member 28-4 includes a lock member 28-4 in which a waveform is formed on the pitch and locking surface of the stator teeth, and a lock member in which rectangular teeth are formed. 3
8-4 may be fixed to the tip of the plunger shaft 18-2.

In addition, as shown in FIG. 3, a surge absorbing diode 7
An excitation coil 2-1 and a transistor 6 are connected in series, and their excitation circuits are arranged in parallel, and a plunger drive circuit consisting of plunger coils 18 to 1 and a surge absorption diode 17 is connected in series. Even if this circuit is constructed in the movable element 11, the movable element can be locked when the power is turned off.

Although the stator teeth 5a are used as the locking members in this embodiment, the present invention is not limited to this, and another member may be provided.

〔Effect of the invention〕

As explained above, according to the present invention, the configuration is extremely simple, and the number of parts can be reduced because the plunger coil shares the excitation coil drive circuit components. Since it is used, it has the advantage of being able to generate a large amount of power when the power is turned off while reducing the power consumption of the plunger coil by 1rl'I, and can be expected to have a significant economical and reliability improvement effect, making it extremely useful industrially. .

[Brief explanation of the drawing]

Fig. 1 is a structure and circuit diagram of a linear pulse motor according to a first embodiment of the present invention, Fig. 2 is a structural diagram showing another second embodiment, and Fig. 3 is a third embodiment. 4 is a structural diagram of a conventional linear pulse motor, and FIG. 5 is a circuit diagram of a conventional linear pulse motor. In the figure, 2-1 is an excitation coil, 5 is a stator, 5a is a stator tooth, 6 is a transistor, 7.17 is a diode, 10 is a power supply, LL21.31 is a mover, 18.28.38 is a plunger, 18-1 is the plunger coil, 18-2 is the plunger shaft, 18-3 is the return spring, 18-4.28-4.38-4 is the locking member, 19 is the mounting bracket, t(1) Fig. 1 Pa (CI> (1)) O2
4th position example fl-Pal T 1 2nd figure Sai 3's castle example green mouth route mouth 3rd figure (Q) (b) Subjugari Ni Y ha Luzmo example Hada Tsujiri Edict figure 4

Claims (2)

[Claims] (1) A linear pulse motor that digitally advances by a predetermined step amount according to a pulse signal, and a plunger coil (18-1) is connected in series with the excitation coil (2-1) in the circuit for driving the excitation coil. At the same time, connect the mover (11
), a moving body (18-2) driven by the plunger coil (18-1), and urging the moving body (18-2) in a direction opposite to the suction direction of the plunger coil (18-1). a biasing member (18-3), and a stator (5).
has a locking member (5a) that engages with the movable body (18-2) and locks the movable element (11) in the biased position of the movable body (18-2). A linear pulse motor featuring (2) The linear pulse motor according to claim 1, wherein the locking member (5a) is a stator tooth.