JPH02209338A - Sheet feeder - Google Patents

Abstract

PURPOSE:To make sheet insertion easy by forming an end serving as a sheet inserting port of an elastic body into a taper form, in a sheet feeder provided with a sheet conveying means which forms a progressive wave in the elastic body and conveying a pressed sheet. CONSTITUTION:Two elastic bodies 5, 5 are connected to a grounded circuit as an electric conductor, and frequency voltage is impressed on a vibrator 1 by a generator 7, thereby generating vibration in these elastic bodies 5, 6. Vibrators 2, 4 generate electric power with the vibration, and as the electric energy is dissipated at an energy absorbing part 8 the vibration is not reflected and it comes to a progressive wave. When bending vibration of the elastic bodies 5, 6 comes to the progressive wave, an outer part of bending has a velocity component in reverse to the forward direction of the progressive wave at all times, and since a sheet comes into contact with the outer side of bending all the time, it is conveyed in reverse to the forward direction of the progressive wave. In this connection, the sheet is inserted from each left ends of the elastic bodies 5, 6, but these left ends are installed in a taper form each, so that the sheet can be inserted in space between these elastic bodies 5 and 6 along the taper form.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Application of the Invention) The present invention relates to a sheet feeding device installed in a computer, a copying machine, a facsimile machine, a word processor, a typewriter, and other various machines equipped with a mechanism for feeding sheets. be.

(Background of the Invention) Conventionally, this type of device has been configured to feed the sheet by forming a traveling wave in an elastic body that clamps the sheet, as disclosed in Japanese Patent Laid-Open No. 59-177243. Ta.

Here, we will discuss the third principle of sheet conveyance in the above proposal.
This will be explained using figures.

The sheet 13 is held between the elastic bodies 11 and 12 with moderate pressure. Progressive bending vibrations (travelling waves) are formed in each of the elastic bodies 11 and 12, and the phase difference between these traveling waves is Since the bending vibration of each of the elastic bodies 11 and 12 advances so that the convex portions of the respective elastic bodies always face the sheet 13 side. At this time, if attention is paid to, for example, a mass point with a convex portion on the surface of the elastic body 11, 12, the mass point generally moves in an elliptical orbit. In FIG. 3, regarding the elastic body 11, when the traveling wave moves to the right, the mass point will draw a clockwise elliptical locus as shown in the figure. Therefore, the movement direction of the mass points of the convex portions of the elastic bodies 11 and 12 is opposite to the direction in which the vibrations progress, and this acts as a force to transport the sheet 13.

On the other hand, in the concave portion, a sheet transporting force is generated in the same direction as the traveling direction, but the pressure is smaller than that in the convex portion, so the frictional force between the sheet 13 and the elastic body 11, 12 is small, and the sheet transporting force is also small. Therefore, the total sheet conveying force acts in the direction opposite to the direction in which the bending vibrations described above proceed.

FIG. 4 shows an example of a device that generates the sheet conveying force as described above, and in the figure, reference numerals 11, 12 and 13 are the elastic body and sheet described above. Also, 14-1. 14-2
．． 15-1 (not shown) and 15-2 are the elastic bodies 11.1
A vibrator fixed on 2, 16 a pressing support member, 17-
1. 17-2 is a support side plate, and 18 is a bottom plate.

The elastic body 12 is supported by a bottom plate 18, and the elastic body 11 is supported by a pressing support member 16.

Further, the elastic body 11 presses the sheet 13 with an appropriate force due to the spring properties of the pressing support member 13, and holds the sheet 13 together with the elastic body 12.
By applying a certain frequency voltage to each vibrator 12 and applying vibration, the respective convex portions are always facing each other as described above, so that a sheet conveying force is generated.
The sheet is conveyed in the direction of the arrow in the figure. Note that the arrows in the figure point in both directions, which means that the direction of sheet conveyance can be reversed by switching the direction of vibration.

FIGS. 5 and 6 show an example of a device (only the main parts are shown) in which the vibrating body is realized with a different configuration.

FIG. 5 shows a track-shaped vibrator 19-1. Similarly track-shaped elastic body 20-1.20-2 to which 19-2 is fixed
The structure is such that the sheet 13 is held between the vibrator 19-
1.19-2 by applying a frequency voltage to the elastic body 20-1.
This apparatus is similar to the apparatus shown in FIG. 4 in that the sheet conveying force is generated by creating progressive bending vibration in the apparatus 20-2.

FIG. 6 is a cross-sectional view of the apparatus shown in FIG. 5 as viewed from the sheet feeding direction, and there is a level difference on the left and right sides. This is the elastic body 20-
1. Since the direction of the sheet transport force is acting in opposite directions on the left and right sides of 20-2, this is to prevent the transport force on the opposite side (the right side in Figure 6) from acting on the sheet 13. be.

By the way, in the conventional device as described above, the distance between the elastic bodies is narrow, and these elastic bodies are pressed to hold the sheet, so it is difficult to insert the sheet between the elastic bodies. .

(Object of the Invention) An object of the present invention is to solve the above-mentioned problems and provide a sheet feeding device that can easily insert sheets.

(Characteristics of the Invention) In order to achieve the above object, the present invention provides a tapered shape at the end of the elastic body that serves as a sheet insertion opening, and has a sheet guiding function at the tapered end. It is characterized by having

(Embodiments of the Invention) Hereinafter, the present invention will be described in detail based on illustrated embodiments.

FIG. 1 shows an embodiment of the present invention, 1.2,
3.4 is a vibrator made of a piezoelectric element, 5゜6 is an elastic body, 7
8 is an oscillator that applies a frequency voltage to the vibrators 1 to 4, and 8 is an energy absorption section.

The vibrators 1 and 2 are fixed to an elastic body 5 with adhesive or the like.

Similarly, the vibrator 3.4 is fixed to the elastic body 6 with adhesive or the like. Further, the elastic bodies 5 and 6 are held down with an appropriate force. In this embodiment, the elastic bodies 5 and 6 are connected to a ground circuit as conductors, and vibration is generated in the elastic bodies 5 and 6 by applying a frequency voltage (alternating current electric field) to the vibrator 1 by an oscillator 7. do. The vibrators 2 and 4 generate electricity as the elastic bodies 5 and 6 vibrate. The generated electrical energy is dissipated by an energy absorbing section 8 made of a resistor or the like. Therefore, the vibration becomes a traveling wave without being reflected. When the bending vibration of the elastic body 5.6 becomes a traveling wave, 1 of the surface of the elastic body 5.6 becomes a traveling wave.
If you pay attention to the point, its trajectory draws an ellipse. Therefore, the outside part of the bend always has a velocity component in the opposite direction to the traveling direction of the traveling wave, and since the sheet is always in contact with the part outside the bend, it has a velocity component in the opposite direction to the traveling direction of the traveling wave. Sent. In FIG. 1, sheets are fed from left to right.

By the way, the sheet is inserted from the left end of the elastic body 5.6 in the figure, but as shown in the figure, the left end of the elastic body 5.6 is tapered, and the sheet is inserted smoothly along the taper. It can be inserted between the elastic bodies 5.6.

FIG. 2 shows another embodiment of the present invention, in which the elastic body 2 shown in FIG.
Instead of 0-1.20-2, a track-shaped elastic body 9-1.9-2 with a tapered sheet insertion opening is used to allow smooth sheet insertion.

According to this embodiment, since the end portion of the elastic body serving as the sheet insertion opening is tapered, the sheet can be inserted smoothly.

(Modification) In this embodiment, both of the elastic bodies 5 and 6 are provided with a tapered shape, but only one of them may be provided.

(Effects of the Invention) As explained above, according to the present invention, the end of the elastic body that becomes the sheet insertion opening is tapered, and the tapered end has a sheet guiding action. This makes it possible to easily insert the sheet.

[Brief explanation of the drawing]

Fig. 1 is a side view showing one embodiment of the present invention, Fig. 2 is a perspective view showing the main parts of another embodiment of the invention, and Fig. 3 is for explaining the sheet conveyance system in this type of device. , FIG. 4 is a perspective view showing the structure of a conventional device, FIG. 5 is a perspective view similarly showing the structure of another conventional device, and FIG. 6 is a sectional view taken from the sheet feeding direction of FIG. 1.2, 3.4... vibrator, 5.6...
- Elastic body, 7... Oscillator, 8... Energy absorption section, 9-1.9-2... Elastic body.

Claims (1)

[Claims] (1) An elastic body to which a vibrator is fixed, and a sheet that is conveyed by applying a frequency voltage to the vibrator to form a traveling wave in the elastic body and applying a transporting force to the sheet pressed against the surface of the elastic body. 1. A sheet feeding device comprising a conveying means, wherein an end of the elastic body serving as a sheet insertion opening has a tapered shape.