JPH0436137Y2 - - Google Patents

Description

[Detailed description of the invention] <Industrial application field> The present invention is a drive device that can be applied as a drive means for devices that move a shaft with a minute diameter (φ0.2 mm to φ0.4 mm) linearly in a minute range. It is related to.

<Prior art and its problems> For example, an actuator using a piezoelectric element used in the printing head of a printer has a flight pin installed at the tip of a leaf spring that is fixed on one side, so the printing rod at the tip does not rotate. Because of this, accurate positioning was not possible. In addition, some types have a flight pin installed at the tip of a leaf spring that is fixed on both sides, but if the rod diameter is minute, the shaft may bend, so the length of the rod must be within a limited range. I can only do it. If it were made longer, there would be drawbacks such as the rod not being able to travel straight.

<Purpose of the invention> In order to eliminate the above-mentioned drawbacks, the object of the invention is to provide a drive device that uses a sliding bearing for the guide of the shaft and has excellent straightness even with a small diameter shaft.

<Structure of the invention> According to the invention, a curved leaf spring with both ends fixed to the upper and lower ends of the inner surface of a frame-shaped casing is provided, and the leaf spring has a spherical tip with high hardness and high repulsion at the center of the back surface of the leaf spring. A spherical tip of the flight pin is pressurized and in contact with the other end of a columnar laminated piezoelectric element whose one end is connected to the inner surface of the frame-shaped housing, A driving device is obtained in which a shaft is fixed to the center of the inner surface of the leaf spring, and the shaft slides on the inner surface of a cylindrical tube embedded in the side surface of the frame-shaped casing.

<Detailed Description of Configuration> An embodiment of the present invention will be described in detail below. FIG. 1 is a perspective view of a driving device according to the present invention. In the figure, reference numeral 1 denotes a frame-shaped housing, and a curved leaf spring 2 with both ends fixed to the upper and lower ends of the inner surface of the housing 1 is provided, and a flight pin 3 with a spherical tip is provided at the center of the back surface of the leaf spring 2. is provided. The flight pin 3 is pressurized by a leaf spring 2, and the other end of the laminated piezoelectric element 4, which is in contact with one end of the laminated piezoelectric element 4, is fixed to the inner surface of the housing 1. A shaft 5 is fixed to the center of the inner surface of the leaf spring 2, and the shaft 5 constantly moves linearly on the inner surface of a plain bearing tube 6 (Teflon tube in this invention) embedded in the center of the side surface of the housing 1. It slides while moving.

Next, the operation will be explained.

When the laminated piezoelectric element 4 is energized, the laminated piezoelectric element 4 expands at high speed, so that the flight pin 3 that is pressurized and in contact with the laminated piezoelectric element 4 is blown in the direction of arrow A. At this time, since the leaf spring 2 also bends, the shaft 5 fixed to the inner surface of the leaf spring also moves in the direction of arrow A. When the shaft 5 moves, it slides against the inner surface of the plain bearing tube, so that the shaft 5 always moves linearly. A certain amount of shaft 5 (0.3mm~0.4
mm), the shaft 5 is returned to its original position by the spring force of the leaf spring 2, and the flight pin 3 is also returned to its initial position. (At this time, the laminated piezoelectric element 4 is de-energized.) <Effect of the invention> According to the invention as described above, by installing the sliding bearing tube 6, the straightness of the shaft 5 can be greatly improved. , the shaft diameter is minutely 0.2
It can be ~0.4mm. Further, since the fixed position of the tip of the flight pin is always in point contact with the end face of the laminated piezoelectric element 4, there is no loss of impact force of the laminated piezoelectric element, resulting in extremely high efficiency. Further, this driving device has the advantage that it can be applied as an actuator for ceramic green sheets, print heads of printers, and the like.

[Brief explanation of drawings]

FIG. 1 is a diagram showing an embodiment of the present invention. In the figure, 1 is a frame-shaped housing, 2 is a leaf spring, 3 is a flight pin, 4 is a laminated piezoelectric element, 5 is a shaft, 6 is a plain bearing tube, and arrow A indicates the direction of movement.

Claims (1)

[Scope of utility model registration request] A curved leaf spring with both ends fixed to the upper and lower ends of the inner surface of the frame-shaped casing is provided, and a flight pin having a spherical tip and made of a material with high hardness and high repulsion is provided at the center of the back of the leaf spring. , the spherical tip of the flight pin is pressurized and in contact with the other end of a columnar laminated piezoelectric element whose one end is connected to the inner surface of the frame-shaped casing, and a shaft is located at the center of the inner surface of the leaf spring. The drive device is fixed, and the shaft slides on the inner surface of a cylindrical tube embedded in the side surface of the frame-like housing.