JPH0370482A - Driving mechanism - Google Patents

Abstract

PURPOSE:To reduce a size and a weight by raising inner hydraulic pressure in a vessel by a heat generator in a mechanism for converting a vibration of an ultrasonic vibrator to a rotating motion, displacing an elastic wall, stopping supply of heat, converting the vibration of the wall to an elliptical motion, and bringing a moving member into contact with an elliptical motion generator to apply a driving force thereto. CONSTITUTION:When a heat generator 17 is energized, bubbles are generated in liquid 15, and pressure in a partition wall is raised. When the generator is deenergized, the bubbles vanish. These operations are repeated to vibrate a vibration wall 14, and a protrusion in contact with a vibration piece 11 is subjected to an elliptical motion. A roller 21 receives torque to rotate. When paper or the like is inserted to the elliptical motion part, it receives a driving force and is moved.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a drive mechanism, and more particularly to a mechanism for converting reciprocating motion of an ultrasonic transducer into rotational motion of a rotating shaft.

Figure 7 shows the conventional ultrasonic transducer structure (Special Publication Publication No. 59-376
72 Publication) is a main part configuration diagram for explaining an example. In the figure, 1 is an ultrasonic transducer, 2 is a rotating shaft, 3 is a vibrating piece, 4 is a diaphragm, 5 is a bearing, and 6 is a bearing. Fixing screw, 7
1 is a nut that fixes the rotating shaft 2, 8 is a coil, 9 is a casing, and IO is a cover member. As shown in the figure, on one side inside the casing body 9, an ultrasonic transducer l is reciprocated in the direction of arrow a. A rotary shaft 2 is rotatably fitted on the other side via a bearing 5, and a diaphragm 4 and one end surface of the rotary shaft 2, that is, a vibrating piece 3 are arranged to face each other. There is. That is, a plate-shaped or rod-shaped vibrating piece 3 is provided integrally with the rotating shaft 2 at an appropriate inclination angle with respect to the axial direction of the rotating shaft 2 on one end surface of the rotating shaft 2. A diaphragm 4 is fixed on one end surface of the acoustic wave element 1, and is held at a position where the diaphragm 4 and the head of the vibrating piece 3 are in contact with each other.

Generally used as a vibrator that generates ultrasonic waves.

Two types of vibrators, magnetostrictive vibrators and electrostrictive vibrators, are currently in practical use, and these vibrators are already known. The vibrator shown here is a magnetostrictive vibrator, and when a high frequency voltage is applied to the coil 8, the ultrasonic vibrator l, which is a magnetostrictive body, expands and contracts due to the magnetic field, thereby exciting the diaphragm 4.

FIG. 8 is an enlarged view of the main part of the ultrasonic transducer section, in which, as shown in the figure, the vibrating piece 3 provided on one end surface of the rotating shaft 2 is connected to the ultrasonic transducer section. 1, is fixed at an appropriate angle with respect to the axial direction of the rotating shaft 2, and is supported by a bearing 5 such as a bearing. To construct the vibrating piece 3, a circular hole having a radius slightly smaller than the cross-sectional radius of the metal rod is hollowed out in the center of one end of the metal rod forming the rotating shaft 2, and the remaining It can be created by adding a cut at a preset angle to the peripheral edge of the .

FIG. 9 is a longitudinal cross-sectional view taken along the line xx' in FIG. 8, in which the vibrating piece 3 is formed by protruding from the peripheral portion of the rotating shaft 2 by cutting.

FIG. 10 is an enlarged view for explaining the actual driving state. First, as shown in FIG. 10(a), one end surface 4a of the diaphragm 4 and one end surface 3a of the vibrating element 3 are in contact with each other. The lowest point is the origin of the X-Y coordinates.

At this time, the inclination 0 of the vibrating piece 3 with respect to the axial direction is made smaller than the friction angle between the vibrating plate 4 and the vibrating piece 3.

Next, when the diaphragm 4 starts vibrating as shown in FIG. 10(b), and the diaphragm 4 is displaced by ΔX in the X direction,
One end surface 3a of the vibrating piece 3 is pushed in the +X direction, but since the rotating shaft 2 is fixed, a component force is generated due to the tilt angle θ and the displacement in the A force pushing up in the force direction acts and moves the rotating shaft 2 by ΔY1. Next, as shown in FIG. 10(C), the diaphragm 4 is moved in the -X direction by -ΔX.
When the end face 4a and the end face 3a are displaced by the amount, the end face 4a and the end face 3a are separated and no frictional force is exerted between them, so that the rotary shaft 2 moves in the +Y force direction due to the period of natural vibration.

However, during this period as well, the rotating shaft 2 is + due to inertia force.
Move by Y force direction ΔY2. Further, as the diaphragm 4 continues to vibrate, it becomes the state shown in FIG. 10(a) again and the above operation is repeated, and the rotation of the rotating shaft 2 continues.

However, in the above-mentioned conventional ultrasonic drive mechanism, both the magnetostrictive vibrator (element) and the piezoelectric vibrator (element) are hard and brittle, and therefore difficult to process and limited in the shape of use. Furthermore, the driving voltage is generally high, which increases the cost of the driver and power supply.

Furthermore, the vibrator itself is large, making it unsuitable for small and thin designs.

In addition, the present invention has been made in part in view of the above-mentioned circumstances.
To create a vibrator that is easy to process and whose shape can be designed freely, convert it into elliptical motion, and create a small, thin, and lightweight drive mechanism. Also, it is possible to create a vibrator with a low driving voltage and reduce costs. and microfabrication technology (etching).

It is possible to construct a multi-oscillator through micro-machining using photofabrication, etc., thereby further increasing the driving force, making it smaller, thinner, and lighter.

This was done for the purpose of

In order to achieve the above object, the present invention includes a heat generating member;
an elastic wall forming part of a container containing a liquid;
The heat generating member generates bubbles in the liquid in the container to increase the pressure in the liquid, displacing the elastic wall surrounding the liquid, and causing the heat generating member to supply heat to the liquid. By stopping the bubble, the bubble disappears and the displacement of the elastic wall returns, converting the vibration of the elastic wall into elliptical motion, and bringing the moving member into contact with the part generating the elliptical motion, thereby causing the movement. An attempt was made to apply a driving force to a member, or a closed container formed at least in part by an elastic wall and filled with a thermal expansion member, a heating means for heating the thermal expansion member, and a heating means for heating the thermal expansion member. By turning on the heating means, the thermal expansion member is heated to increase the pressure inside the sealed container, and when the heating means is turned off, the thermal expansion member contracts and the pressure inside the sealed container is decreased. The movable member includes a vibration generating mechanism that generates vibrations in the elastic wall, converts the vibration of the elastic wall into elliptical motion, and brings the movable member into contact with a portion that is making the elliptical motion. It is characterized by providing driving force to. Hereinafter, the present invention will be explained based on examples.

FIG. 1 is a block diagram for explaining the present invention in detail, in which 1 is a vibrating element, 12 is an elastic thin film, 13 is a partition wall, and 14 is a configuration diagram for explaining the present invention in detail.
1 is a vibrating wall, 15 is a liquid, 16 is a lead electrode, 17 is a heating element, 18 is a base/heat sink, 19 is an insulator, 20 is a power source, 21 is a roller, and the upper surface of the base 18 which also serves as a heat sink is an insulator. A heating element 17 and a lead electrode 16 are formed on the insulator 19 by sputtering, vapor deposition, or the like. A container is constituted by a partition wall 13, a vibrating wall 14, etc., and a liquid 15, for example, is contained in this container.
Contains water etc. The vibrating wall 14 is supported by an elastic thin film 12, and a T-shaped vibrating piece 11 is fixed thereto. The protrusion at the tip of the vibrating piece 11 is positioned slightly offset from the central axis of the roller 21, which is supported for one rotation, and is in elastic contact with the roller surface. The lead electrode 16 includes
Voltage is supplied from a power supply 20. When electricity is applied to one heating element 17 by a driver (not shown), bubbles are generated in the liquid 15, and the pressure inside the partition wall increases. When the electricity is turned off, the bubbles are cooled by the surrounding liquid and the base element 8, contract, and disappear. By repeating this, the liquid pressure moves up and down, and the vibrating wall 14 vibrates. This results in
The vibrating piece 11 vibrates toward the center of the roller 21, and the protrusions in contact form an elliptical motion. This elliptical motion causes the roller 21 to receive torque and rotate clockwise. When a piece of paper, for example, is inserted into the elliptical movement part, the paper receives active force and moves.

FIGS. 2 and 3 are diagrams for explaining an embodiment in which a plurality of drive mechanisms shown in FIG. 1 are provided on the circumference and configured as a cylindrical motor.

22 is the left case, 23 is the right case, 24 is the rotor, 25
is a radial bearing, 26 is a thrust bearing, 2
7 is a fixing screw, 28 is a push screw, and the rotor 24 is a T-shaped rotor consisting of a flat plate portion 24a and a shaft portion 24b. In addition, other parts having the same functions as those in the embodiment shown in FIG. 1 are given the same reference numerals as in the case of the first construction drawing. Therefore, in this embodiment, the second
As shown in the figure, a plurality of vibrating pieces 11 are pressed against the flat plate portion 24a of the T-shaped rotor 24.
The tip portion of No. 1 is inclined at a certain angle. The rotor 24 is rotationally supported by a radial bearing 25,
A thrust bearing 26 pressed by a push screw 28 obtains a pressing force against the vibrating piece 1 and at the same time reduces friction.

FIG. 3 is a view of FIG. 2 viewed from the right side with the rotor 24 removed, and as shown, the vibrating pieces 11 are lined up on the circumference. When current is applied to the heating element 17 using a driver (not shown), bubbles are generated in the liquid 15, and the pressure inside the partition wall 13 increases. When the current is removed, the bubbles disappear and the pressure drops. This repetition causes the vibrating wall 14 to vibrate, which is transmitted to the vibrating piece 11. Since the tip of the vibrating piece 11 is inclined, the contact portion with the flat plate portion 24a of the rotor 24 forms an elliptical motion and applies rotational force to the rotor 24.

4 and 5 are configuration diagrams for explaining an example of the case where the drive mechanism according to the present invention is applied to paper feeding. FIG. 4 shows a side view, and FIG. 5 shows a plan view. Inside, 30 is a base, 31 is a piezoelectric element, 32 is a diaphragm, 33, 34 is a roller, 35 is paper, 36 is a guide plate, 36a is a presser spring (a part of the guide plate 36), and 40 is a heat generating vibrator. , the heating vibrator 40 includes the above-mentioned partition wall 13, vibrating wall soil 4, liquid 15, lead electrode 16, heating element 17, base 18, and insulator top 9.
It consists of etc. The embodiment shown in FIGS. 4 and 5 utilizes a piezoelectric element when converting the vibration generated by the heat generating vibrator 40 into elliptical motion, and the diaphragm 32 is mounted on the vibrating wall 14. The diaphragm 32 is fixed in place, and as the heating element 17 is turned on and off, the diaphragm 32 vibrates from side to side in FIG. 4.

A piezoelectric element 31 fixed to the base 30 is driven in accordance with the phase of the diaphragm 32 according to the feeding direction of the paper 35. With this configuration, the vibration of the diaphragm 32 is converted into elliptical motion, and a driving force is applied to the paper 35 that is in contact with the diaphragm 32. To ensure contact, roller 3
3 and 34 are pressed by a presser spring 36a.

As the heating means, a heating element may be used as in the above embodiment, or external heating, such as laser heating, may also be used to achieve the purpose. Of course, cooling means may be provided as necessary to enhance response.

In addition, although this example uses bubbles generated in the liquid,
As shown in claim 2, it is also possible to utilize expansion and contraction of the thermal expansion member 1, such as paraffin, by heating.

FIG. 6 is a diagram showing a specific example of the heating element 17.
) is a plan view, (b) is a side view, and in the figure, 17a is S.
i substrate (550μm), 17b is Si0.2, oxide layer (
5,0μm), 17c is a HfB2 resistor (0,13μm)
), 17d is AQ electrode (0.5μrn) 17e is S
io2 insulating layer (2.56 μm), ↓7f is Ta protective film (
0.45 μm), and its fabrication consists of a smooth S layer with a 5 μm thick oxide layer 17b formed by heat treating the surface.
On the i-substrate 17a, a layer with a thickness of 0.0 mm is formed by sputtering.
After forming an AQ layer 17d with a thickness of 0.5 μm using EB evaporation of 13 μm of I(fBJ517c), patterning the resistor 17c and electrode 17d by etching, and patterning the resistor 17c and electrode 17d with a thickness of 2.56 μm by sputtering.
SiO□ insulating film 17e and 0.45 μm thick Ta
It is manufactured by forming a protective film 17f.

- As is clear from the above explanation, according to the present invention, constituent parts such as heating elements and elastic thin films can be produced using microfabrication techniques such as etching and photolithography, making them ultra-compact and highly accurate. It has features such as:

The heating element operates at a voltage of about 10 to 20 V, allowing low voltage driving.

We create a vibrator that is easy to process and can be designed in any shape.
By converting this into elliptical motion, it is possible to create a compact, thin, and lightweight drive mechanism.

It is possible to create a vibrator with a low driving voltage and reduce costs.

By micro-fabrication technology (etching, photofabrication, etc.), it is possible to construct a multi-oscillator, and it is possible to further increase the driving force and further reduce the size, thickness, and weight of the vibrator.

There are advantages such as

[Brief explanation of drawings]

FIG. 1 is a block diagram for explaining one embodiment of a drive mechanism according to the present invention, FIGS. 2 and 3 are block diagrams for explaining another embodiment of the present invention, and FIG. 5 is a block diagram for further explaining another embodiment of the present invention, FIG. 6 is a diagram showing the structure of one heat generating section, and FIGS. 7 to 10 are examples of conventional active mechanisms. FIG. DESCRIPTION OF SYMBOLS 11... Vibrating piece, 12... Elastic thin film, 13... Partition wall 14... Vibrating wall, 15... Liquid, 16... Lead electrode 17... Heat generating element, 18... Base (Heat sink) 19...Insulator, 20...Power source, 21...Roller, 22.23...Case, 24...Rotor, 30
...Base, 3 parts...Piezoelectric element, 32...Vibration plate, 33.34...Roller, 35...Paper, 36...
guide board. Figure 1 Figure Figure Figure 6 +a1 7

Claims (1)

[Scope of Claims] 1. It has a heat generating member and an elastic wall forming a part of a container containing a liquid, and the heat generating member generates bubbles in the liquid in the container. By increasing the pressure in the liquid, displacing the elastic wall surrounding the liquid, and stopping supplying heat from the heat generating member to the liquid, the bubbles disappear and the displacement of the elastic wall returns. A drive mechanism characterized in that the vibration of the elastic wall is converted into elliptical motion, and the movable member is brought into contact with a portion where the elliptical motion is occurring to apply a driving force to the movable member. 2. A closed container formed at least in part by an elastic wall and filled with a thermal expansion member, a heating means for heating the thermal expansion member, and heating the thermal expansion member by turning on the heating means. a vibration generating mechanism that increases the pressure inside the hermetic container and turns off the heating means, thereby causing the thermal expansion member to contract, the pressure inside the hermetic container to drop, and to generate vibrations in the elastic wall; A drive characterized in that a driving force is applied to the moving member by converting the vibration of the elastic wall into an elliptical motion and bringing the moving member into contact with a portion that is making the elliptical motion. mechanism.