JPH0496673A - Harmonic drive electrostatic motor - Google Patents

Abstract

PURPOSE:To simplify fabrication of stator and to reduce the fabrication cost by insert molding a plurality of driving electrode pieces to a synthetic resin stator casing and exposing the rotor rolling face of each driving electrode from the stator casing. CONSTITUTION:In a stator 1, driving electrodes P1-P8 are normally insert molded at the time of molding of a stator casing 2. For example, a plurality of driving electrode pieces P1-P8 are set in a mold which is then poured with phenol resin thus integrally molding the driving electrodes P1-P8 and the stator casing 2. Resin is also filled in the gap 4 between the driving electrodes P1-P8 to form a spacer section 6 having surface not projecting from the rotor rolling face(inner circumferential face) 5 of the driving electrodes P1-P8. Preferable, the driving electrodes P1-P8 are made flush to the spacer section 6 thus forming a smooth cylindrical face.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a harmonic drive type electrostatic motor, which is a type of electrostatic motor.

[Background Art] A harmonic drive type electrostatic motor uses a temporal change in capacitance obtained by applying a drive voltage between a plurality of drive electrodes formed on a stator and a rotor as a drive energy source. Since it has a two-dimensional configuration, miniaturization is possible.

For this reason, research on harmonic drive type electrostatic motors is underway with the aim of putting them into practical use.

What is shown in FIGS. 4(a) and 4(b) is the structure of the currently proposed harmonic drive type electrostatic motor.
It is composed of a stator 51 and a rotor 61. The stator 51 has a cylindrical metal stator casing 52.
The inner circumferential surfaces of the drive electrode plates TI, T2.
... are arranged with an air gap (groove) 54 therebetween, and the insulating layer 53 connects each drive electrode plate Tl, T2 . ... are adhesively fixed to the inner peripheral surface of the stator casing 52, and the drive electrode plates Tl, T2 . A rotor rolling surface 55 is formed on the inner circumferential surface of...

[Problems to be Solved by the Invention] However, in manufacturing the stator used in the harmonic drive type electrostatic motor as described above, a plurality of pieces are driven by an insulating layer made of an insulating adhesive on the inner peripheral surface of the stator casing. Since each electrode is fixed with adhesive, the work of gluing multiple pieces of drive electrodes to the stator casing one by one is complicated, and the position adjustment of each drive electrode is troublesome, which adds time and effort to manufacturing and processing the stator. was hanging. For this reason, the manufacturing cost of the stator has been high.

In addition, this stator has a three-layer structure consisting of a stator casing, an insulating layer, and a drive electrode, so it is thick and bulky, which hinders the miniaturization of harmonic drive type electrostatic motors. It had become.

Furthermore, the stator casing is made of metal, so it is heavy.

The present invention has been made in view of the above-mentioned technical background, and its purpose is to simplify the production of a stator, reduce the production cost, and further provide a lightweight and compact harmonic drive type electrostatic motor. It is about providing.

[Means for Solving the Problems] The harmonic drive type electrostatic motor of the present invention includes a stator including a plurality of drive electrodes, row and night electrodes that roll along the rotor rolling surface of the stator, and a rotor electrode. In a harmonic drive type electrostatic motor, which consists of an insulating film that electrically insulates the drive electrodes, multiple drive electrodes are insert-molded into a synthetic resin stator casing, and the rotor rolling surface of each drive electrode is separated from the stator casing. It is characterized by being exposed.

[Function] In the present invention, since the drive electrode is insert-molded into the stator casing made of synthetic resin, a plurality of pieces of the drive electrode can be integrally molded with the stator casing at once. For example, it can be manufactured by simply setting a plurality of pieces of drive electrodes in a molding die, injection molding a molding resin into the mold, and removing the mold after curing. Therefore, the conventional work of applying an insulating layer and the work of adhering each drive electrode to the stator casing and fixing it in a predetermined position can be eliminated, and the manufacturing process of the stator can be extremely simplified.

Therefore, the mass productivity of the stator is improved, and the manufacturing cost of the stator can be reduced.

Furthermore, since there is no need for an insulating layer and the drive electrodes are buried within the stator casing, the thickness of the stator can be reduced.
The motor can be made smaller as the stator becomes thinner. Alternatively, the hollow internal space within the stator can be expanded.

Furthermore, since the stator casing is made of resin, the stator is lightweight, and the motor itself is also lightweight.

Furthermore, since the drive electrodes are integrally molded with the stator gaging, there is no risk of peeling off unlike with bonded drive electrodes, and the durability of the stator is improved.

[Example code] Embodiments of the present invention will be described in detail below with reference to the accompanying drawings.

FIGS. 1(a), 2(b) and 2 show a schematic configuration of a harmonic drive type electrostatic motor A according to an embodiment of the present invention, in which a stator 1, a rotor 11 and a drive control section 21 are shown.
It consists of

As shown in FIGS. 1(a) and 1(b), the stator 1 has multiple poles (in the illustrated example, , 8 poles) are embedded at regular pitches along the circumferential direction. The stator 1 has drive electrodes P1 to P8 inserted therein by a conventional method during molding of the stator casing 2. Although not shown, for example, a plurality of pieces of drive electrodes P are placed in a molding die.
The drive molds FiP1 to P8 and the stator casing 2 can be integrally molded by setting the drive molds FiP1 to P8 and injecting a phenol resin or the like into a molding die.

Alternatively, the stator 1 may be manufactured by extrusion molding the stator casing 2 while inserting a long drive electrode material, and cutting the insert molded product into an appropriate length. Further, the gap portion 4 between the drive electrodes 21 to 28 is also filled with resin to form a spacer portion 6.
The surfaces of the drive types tfxP1 to P8 are designed not to protrude from the rotor rolling surfaces (inner peripheral surfaces) 5. Of course, it is desirable that the driving electrodes P1 to P8 and the surface of the spacer portion 6 form a smooth cylindrical surface that corresponds to the road surface. In this way, drive electrodes P1 to PF3 and stator casing 2
By integrally molding the drive electrodes P1 to P8 and making the stator 1 a resin molded product of the drive electrodes P1 to P8, the structure of the stator 1 is simple and mass production is extremely good, so the cost of the stator 1 can be significantly reduced. I can do it. In addition,
If a recess or groove is provided on the side surface of the drive electrode, or if a taber process is applied to the side surface of the drive electrode, the strength of embedding the drive electrode will be increased due to the anchor effect.

A metal hollow cylindrical or solid cylindrical rotor 11 whose outer diameter is smaller than the inner diameter of the stator 1 is inserted into the stator 1.
has almost the same length. The rotor 11 consists of a metal rotor electrode 12 and an insulating film 13, and the outer peripheral surface or the entire surface of the rotor electrode 12 is insulated so that the drive electrodes P1 to P8 and the rotor electrode 12 are not electrically connected. It is covered with a dielectric or dielectric insulating film 13. Of course, the insulating film 13 may not be provided on the rotor 11 but may be provided on the inner peripheral surface of the stator 1. Rotor electrode 12
is always grounded via a support (not shown).

On the other hand, the drive control section 21 of the harmonic drive type electrostatic motor A includes a DC power supply 23, an oscillator 22, and a switching circuit 24, as shown in FIG. A switching circuit 24 is connected to each drive electrode P1 to P8 via a drive electrode cable 25, and the switching circuit 24 applies a drive voltage V from a DC power supply 23 in tune with a signal from an oscillator 22. The driving electrodes P1 to P8 are sequentially switched.

What is shown in FIG. 3 is a time chart showing changes in the voltage of each drive electrode P1 to P8 controlled by the switching circuit 24. In this way, each drive electrode P1~
P8 is caused to move the application position of the drive voltage ■ one by one in the circumferential direction by the switching circuit 24, so that the direction in which the rotor 11 is attracted by the electrostatic attraction force sequentially moves counterclockwise, and thereby the rotor 11 It rolls on the inner circumferential surface of the stator 1 and revolves counterclockwise, and at the same time rotates clockwise (in the direction of the arrow in FIG. 2). Note that this driving method is just an example, and for example, voltage application positions may be switched while applying voltage to a plurality of drive electrodes simultaneously.

In the stator 1 described above, the gap portion 4 between the drive electrodes P1 to P8 is filled with the spacer portion 6, and the rotor rolling surface 5 is smooth, so that the rotor 11 rolls along the inner circumferential surface of the stator 1. When moving, the rotor 11 can be smoothly transferred without falling into the gap portion 4, and no impact noise is generated.

In the above embodiment, drive electrodes are provided on the inner peripheral surface of the stator casing, and the rotor is inserted into the hollow internal space of the stator (inner rotor method). The present invention is not limited to type electrostatic motors, but can also be implemented in motors in which drive electrodes are provided on the outer circumference of the stator casing and a cylindrical rotor is fitted around the outer circumference of the stator (outer rotor type).

[Effects of the Invention] According to the present invention, since the drive electrode is insert-molded into the stator casing made of synthetic resin, a plurality of pieces of the drive electrode can be integrally molded with the stator casing at once, and the manufacturing process of the stator can be simplified. can be done extremely easily. Therefore, the mass productivity of the stator is improved, and the manufacturing cost of the stator can be reduced.

Furthermore, since the structure of the stator is simplified, the thickness of the stator can be reduced, the bulk of the stator can be reduced, and the motor can be made smaller.

Furthermore, since the stator casing is made of resin, the stator can be made lighter and a smaller and lighter harmonic drive type electrostatic motor can be manufactured.

Furthermore, since the drive electrodes are integrally molded with the stator casing, there is no risk of them peeling off unlike with bonded drive electrodes, and the durability of the stator is improved.

[Brief explanation of drawings]

FIGS. 1(a) and 1(b) are a front view and a sectional view showing an embodiment of the present invention, FIG. 2 is a schematic configuration diagram showing a method of driving the same motor, and FIG. 3 is a diagram showing each drive electrode of the above. Time charts showing changes in applied voltage, FIGS. 4(a) and 4(b) are a front view and a sectional view of the harmonic drive type electrostatic motor described in the background art section. l... Stator 2... Stator casing P1 to P8... Drive electrode 5... Rotor rolling surface 11... Rotor 12... Rotor electrode 13... Insulating film

Claims (1)

[Claims] (1) A harmonic drive type electrostatic charger consisting of a stator equipped with multiple drive electrodes, a rotor electrode that rolls along the rotor rolling surface of the stator, and an insulating film that electrically insulates the rotor electrode and drive electrode. A harmonic drive type electrostatic motor is characterized in that a plurality of pieces of drive electrodes are insert-molded in a stator casing made of synthetic resin, and the rotor rolling surface of each drive electrode is exposed from the stator casing.