JP2676758B2 - Paper feed mechanism - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial application] The present invention relates to a paper feeding mechanism used in a printer, a copying machine or the like.

[Prior Art] Conventionally, a paper feed mechanism of this type sandwiches paper between two rollers and feeds the paper by rotation of these rollers.
A motor, a gear or the like was used as the roller rotating means. That is, the rotation of the motor is reduced by a gear or the like, and the rotation of the motor is transmitted to the rollers.

[Problems to be Solved by the Invention] In the above-described conventional paper feeding mechanism, since the motor and the gear act as the roller rotating means, a place for accommodating them is required in addition to the rollers, and the entire paper feeding mechanism is provided. It has the drawback of becoming large. Further, since noise is generated by the motor and the gears, there is a drawback that the housing housing the motors and the gears needs to be soundproofed.

[Means for Solving the Problems] The present invention has been made to solve the above-mentioned conventional problems, and as a means for solving the problems, a driving roller that feeds a sheet by sandwiching and rotating the sheet, In a paper feed mechanism including a roller that rotates in contact with the driving roller, the driving roller includes a plurality of discs and two sets that sequentially connect the plurality of discs and apply two bending vibrations orthogonal to each other. Of the piezoelectric ceramics, and a sine wave having the same frequency as the sine wave voltage and a phase difference of 90 ° to the other set. The present invention provides a paper feeding mechanism characterized by driving and rotating a driving roller by applying a voltage.

Example Next, an example of the present invention will be described with reference to the drawings.

1 and 2 are perspective and side views showing a paper feeding mechanism according to an embodiment of the present invention, and FIGS. 3 to 5 are plan views showing driving rollers of the paper feeding mechanism of FIG. , Front view, side view, and FIGS. 6 to 8 are a plan view, a front view, and a side view showing a driving roller of a paper feeding mechanism according to another embodiment of the present invention.

The paper feeding mechanism includes a driving roller 1 and the driving roller 1
And a roller 6 that rotates in contact with.

The driving roller 1 is composed of three discs 2 and a square rod 3 that sequentially connects the three discs 2.

The three discs 2 have the same shape and rotate in the same direction around the square rod 3 as an axis. The intervals between the three discs 2 are set to be substantially equal.
The rectangular rod 3 has a substantially rectangular cross section, and driving piezoelectric ceramics 4 and 5 are adhered to the surface thereof.

The piezoceramics 4, 5 are, as shown in FIGS. 3 and 4,
The piezoceramics 4, 5 are arranged alternately on the temporary surface of the square rod 3, so that the piezoceramics 4, 5 are at mutually orthogonal positions.

 Next, the operation of this embodiment will be described.

In FIGS. 3 and 4, the positive and negative signs attached to the piezoelectric ceramics 4 and 5 indicate the polarization directions of the piezoelectric ceramics 4 and 5, and indicate the polarities of the surfaces of the piezoelectric ceramics 4 and 5.

When a sinusoidal voltage is applied to the piezoelectric ceramic 5, bending vibration in the X direction is generated as shown in FIG. Similarly, when a sinusoidal voltage is applied to the piezoelectric ceramic 4, bending vibration in the Y direction is excited as shown in FIG. Here, if the frequencies of the sine wave voltages applied to the piezoelectric ceramics 4 and 5 are set to be the same and the phase difference is set to 90 °,
The disc 2 of the driving roller 1 makes a circular movement in the direction of the arrow or in the opposite direction along the dotted circle as shown in FIG. As a result of this circular movement, the sheet 7 sandwiched between the disk 2 of the driving roller 1 and the roller 6 is fed to one side as shown in FIG.

When the frequency of the driving voltage of the driving roller 1 is set to the ultrasonic band of 20 KHz or higher, no noise is generated.

As described above, the disc feed mechanism 2 of this embodiment is the disc 2
Since it is composed of the driving roller 1 having a simple structure including the square bar 3 having the piezoelectric ceramics 4 and 5 attached to the surface connecting the two and the simple roller 6, the miniaturization is easy. Further, since gears, motors, etc. are not used, a space for accommodating them is unnecessary, and as a result, the device itself can be downsized. Further, by reversing the phase difference of the sine wave voltage applied to the two sets of piezoelectric ceramics 4 and 5, it is extremely easy to reverse the feeding direction of the paper 7.

In the paper feeding mechanism according to another embodiment shown in FIGS. 6 to 8, the driving roller 11 is composed of four discs 2 and a square rod 3 in which the four discs 2 are sequentially connected. About the configuration of the first
It is the same as the paper feed mechanism shown in the figure. Piezoelectric ceramics 5 and 4 which are polarized as shown in FIGS. 6 and 7 are adhered on the square rod 3, respectively. By applying a sine wave voltage to these piezoelectric ceramics 4 and 5, as shown in the figure. X
The bending vibration in the direction and the bending vibration in the Y direction are excited.

Since the driving roller 11 of this embodiment has the structure in which the number of the discs 2 is increased, the force for feeding the sheet 7 becomes strong and the length of the roller 6 can be lengthened to feed the sheet 7 having a wide width. Become. Similarly, by increasing the number of circular plates 2, it is possible to realize a paper feeding mechanism capable of feeding a wide width paper 7.

EFFECTS OF THE INVENTION As described above, in the paper feeding mechanism of the present invention, the driving roller has a plurality of discs and two sets that sequentially connect the plurality of discs and give two bending vibrations orthogonal to each other. Of the piezoelectric ceramic of the above two sets, a sine wave voltage is applied to one of the two piezoelectric ceramics, and a sine wave having the same frequency as the sine wave voltage and a phase difference of 90 ° is applied to the other set. Since the driving roller is driven and rotated by applying the wave voltage, the structure is simplified, and as a result, the device can be downsized. Further, by selecting the frequency of the sine wave voltage applied to the piezoelectric ceramic in the ultrasonic band, there is also an effect that a paper feeding mechanism having no noise can be realized.

[Brief description of the drawings]

1 and 2 are perspective and side views showing a paper feeding mechanism according to an embodiment of the present invention, and FIGS. 3 to 5 are plan views showing driving rollers of the paper feeding mechanism of FIG. , Front view, side view, and FIGS. 6 to 8 are a plan view, a front view, and a side view showing a driving roller of a paper feeding mechanism according to another embodiment of the present invention. 1,11: Driving roller 2: Disc 3: Square bar 4,5: Piezoelectric ceramic 6: Roller 7: Paper

Claims (1)

(57) [Claims] 1. A paper feeding mechanism comprising a driving roller for feeding a paper by rotating the nipping paper, and a roller rotating in contact with the driving roller, wherein the driving roller comprises a plurality of discs. These two discs are connected one after another, and two bending vibrations orthogonal to each other are applied.
A pair of piezoelectric ceramics and a square bar bonded to the side surface,
A sine wave voltage is applied to one of the two piezoelectric ceramics,
A paper feed mechanism characterized in that a driving roller is driven and rotated by applying a sine wave voltage having the same frequency as the sine wave voltage and a phase difference of 90 ° to the other set.