JPS62285834A - Paper feed device - Google Patents

Abstract

PURPOSE:To make it possible to eliminate the necessity of means for transmitting drive force to simplify the arrangement of a paper feed device, by exciting a progressive elastic wave through a drive member composed of a piezoelectric material and an elastic material, and by setting a paper on the drive member being made in contact with the latter. CONSTITUTION:An elastic member 3 formed in the lower side section thereof with concave and convex parts, are bonded to the lower surface of a piezoelectric ceramic body 1 to form a drive member 4. Meanwhile dampers 5 having a function of absorption for elastic waves are connected to both ends of the drive member 4 so that elastic waves are prevented from reflecting at both ends thereof. Contact pressure is exerted between the piezoelectric drive member and a bundle of paper sheets by means of a spring 7 from the opposite side of the paper sheets 6, and therefore, the paper sheets are successively fed in the direction of the arrow 8 by a progressive wave effected by piezoelectric drive. The speed of the paper feed may be optionally changed by adjusting the velocity of the progressive wave effected through the piezoelectric drive member, thereby it is possible to control the feed of paper sheets in accordance with several kinds of.

Description

Detailed Description of the Invention 3. Detailed Description of the Invention Field of Industrial Application The present invention relates to an ultrasonic vibration application paper feeding device that generates driving force using a piezoelectric body.

2. Description of the Related Art Conventionally, many paper feeding devices have been used in copying equipment, printing equipment, etc. As shown in FIG. The structure is such that the paper is sent by applying force and pressing the paper against the rotating roller 33.The driving force for this roller is provided by transmitting the rotation of an electric motor 34 to the roller 33 through a pulley 35 and a belt 36. These are actually incorporated into the above-mentioned devices and have been used for general purposes for a long time.On the other hand, recently, elastic vibrations have been excited in driving bodies using piezoelectric materials such as piezoelectric ceramics.

Ultrasonic motors are being developed using this as driving force. Figure 4 shows an example of an ultrasonic motor.

An annular piezoelectric plate is provided on one side of the annular surface of the annular elastic body 41.
A piezoelectric drive body 43 is constructed by bonding the micrometers 42 together. 44 is a slider made of wear-resistant material.

45 is an elastic body, which is pasted together to form the moving body 4.
6. The moving body 46 is in contact with the driving body 43 via the slider 44. When an electric field is applied to the piezoelectric ceramic 42, a traveling wave for bending imaging is excited in the circumferential direction of the driving body 43, thereby driving the moving body 46''. Note that the arrow in the figure indicates the rotation direction of the moving body 46. At this time, in order to smoothly drive the moving body 46, a suitable contact force is required between the driving body 43 and the moving body 46, and therefore a magnet or the like is usually used for the elastic body 45.

A magnetic circuit is formed with the elastic body 41 of the driving body part to obtain the necessary contact force.

These ultrasonic motors are described in Mori et al.; Acoustical Society of Japan Proceedings 1-2-1 (1985, 3) 579.

Problems that the invention seeks to solve Conventional paper feeding devices such as copying machines use electric motors,
Since rollers are used to convert two rotational motions into linear motions of the paper, these spaces are necessary and an unnecessary volume is required for only one essential paper feeding function. An object of the present invention is to eliminate these drawbacks and to provide an ultrasonic paper feeding device that is extremely small in volume and highly efficient, having only the paper feeding function by applying the principle of an ultrasonic motor.

Means for Solving the Problems A traveling elastic wave is excited in a driving body made of a piezoelectric body and an elastic body, and the paper is moved by placing the paper in contact with the driving body.

Since the driving force of the actuator directly acts on the paper, no means for transmitting the driving force is required, and the structure is extremely simple and compact.

Embodiments Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

Embodiment 1 FIG. 1 shows an ultrasonic paper feeding device according to an embodiment of the present invention. In the figure, 1 is a piezoelectric body such as a piezoelectric ceramic for exciting traveling waves in a rectangular parallelepiped piezoelectric drive body, which is polarized in the thickness direction and has a plurality of electrodes 2 in the longitudinal direction of the two plates. . Using these electrodes, the phases of the two standing waves 9 and 10 are shifted temporally and spatially, respectively, and the traveling waves are transferred to the power source E.
l, formed by E2. Below the piezoelectric ceramic 1, an elastic body 3 having irregularities formed further below is adhered to constitute a driving body 4. On the other hand, dampers 5 having a function of absorbing the elastic traveling waves generated as a result of the above are connected to both ends of the driving body 4 to prevent reflection of one elastic traveling wave from the ends. From the opposite side of the paper 6, a spring 7 applies contact pressure between the piezoelectric driver and the paper bundle, and the sheets 9 are sequentially sent in the direction 8 of the arrow in the figure by a traveling wave generated by the piezoelectric driver. The paper feeding speed can be freely changed by adjusting the speed of the traveling wave of the piezoelectric drive body, and can be controlled according to various purposes. Although even one paper feeding device of the present invention has a paper feeding function in principle.

In order to stably feed a large sheet of paper, it is necessary to line up a plurality of them in contact with the paper at right angles to the paper feeding direction, as shown in Figure 1. This paper feeding device requires only a piezoelectric drive body and a spring, and eliminates the need for conventional drive units such as electric motors and rollers. As a result, space savings and cost reductions can be expected.

Embodiment 2 FIG. 2 shows another embodiment of the invention. As in Example 1, in the figure, 21 is a piezoelectric material such as piezoelectric ceramic for exciting traveling waves in the elliptical belt type piezoelectric driver, which is polarized in the thickness direction and replicated in the circumferential direction of the plate. side electrode 22
is formed. Using this electrode, the phases of the two standing waves are shifted temporally and spatially, and the traveling wave is converted into an electric ionic wave.
E1. Formed by E2. An elastic body 23 having irregularities formed further below is adhered to a portion of the piezoelectric ceramic 21 that contacts the paper, thereby forming a paper feed drive body 24. From the opposite side of the paper 25, a contact pressure is applied between the piezoelectric paper feed drive body and the paper stack by a piston 26, and the nine papers are sequentially fed in the direction of an arrow 27 in the figure by a traveling wave generated by the piezoelectric drive body. The paper feeding speed can be freely changed by adjusting the speed of the traveling wave of the piezoelectric drive body, and can be controlled according to various purposes. In this case, if the piezoelectric body forms a closed loop as in this embodiment, a stable traveling wave is generated and smooth paper feeding can be realized. This retarding device requires only a piezoelectric drive body and a spring, eliminating the need for conventional drive units such as electric motors and rollers. As a result, space savings and cost reductions can be expected.

In the above embodiments, the piezoelectric ceramic used is generally lead zirconium titanate (PZT), but the material is not limited to this, and any material can be used as long as it exhibits piezoelectricity. . Further, although the above-mentioned two types of driving bodies are shown, the driving body is not limited to these, but is not limited to any shape as long as it generates a stable standing wave.

Effects of the Invention As described above, by applying the principle of an ultrasonic motor, the paper feeding device of the present invention can realize a paper feeding device that eliminates unnecessary functions, which was not possible in the past, and as a result, it saves space. It has the effect of lowering prices.

[Brief explanation of the drawing]

FIG. 1(a) is a perspective view of a paper feeding device according to an embodiment of the present invention, FIG. 1(b) is an enlarged sectional view of its main parts, and FIG. FIG. 3 is a sectional view of a conventional paper feeding device, and FIG. 4 is a side view of a conventional ultrasonic motor. DESCRIPTION OF SYMBOLS 1... Piezoelectric ceramic, 2... Electrode, 3... Elastic body, 4... Drive body, 5... Damper, 6... Paper,
7... Spring, 8... Paper feeding direction, 9, 10... Standing wave.

Claims (3)

[Claims] (1) A paper feeding device characterized in that a driving body made of a piezoelectric body and an elastic body excites an elastic traveling wave, and the paper is moved by bringing the paper into contact with the piezoelectric driving body. (2) A paper feeding device according to claim 1, characterized in that a plurality of piezoelectric drive bodies that excite traveling waves in the paper feeding direction are arranged in contact with the paper at right angles to the paper feeding direction. (3) The paper feeding device according to claim 1, wherein the piezoelectric body forms a closed loop.