JPH07125894A - Printer having mechanism for adjusting pressure of paper feeding roller - Google Patents

Abstract

PURPOSE:To detect lowering of the pressure of a paper feeding roller to prevent the paper feeding failure. CONSTITUTION:A printer having a mechanism for adjusting pressure of paper feeding roller is provided with a paper feeding roller 8 for carrying continuous papers 1 at a constant speed and a measuring means formed of a buffer arm 10, which is made to pressure-contact with the continuous paper 1 by the spring force freely to be rotated around of a shaft, and a buffer arm sensor 12 for measuring angle of this buffer arm 10. A paper pushing force adjusting means for adjusting the paper pushing force of a paper feeding roller formed of a plate sprig 81, which suspends a pushing roller 82 at one end thereof, a block fitted to the other end of the plate spring 81, and a motor for moving the block in the direction for deflecting the plate spring 81 is provided. A paper feeding roller control unit for outputting the paper pushing force adjusting signal to the paper pushing force adjusting means in response to quantity of the paper tensile force is provided.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a printer device having a paper feed roller pressure adjusting mechanism, and more particularly to a printer device having an electrophotographic type paper feed roller pressure adjusting mechanism used for a copying machine or computer output.

[0002]

2. Description of the Related Art FIG. 5A is an overall view showing a first example of a conventional printer device. Referring to FIG. 5A, the continuous paper 1 is conveyed to the transfer unit 21 by the tractor 2,
A latent image is formed on the photoconductor 4 by the laser light 3 and the visualized image is transferred by the developing device 5. The continuous paper 1 is again sent to the fixing unit 6 by the tractor 2. The fixing unit 6 is provided with a lamp unit 7 that fixes the toner by the flash light energy. The paper feed roller 8 is the fixing unit 6
The continuous paper 1 is discharged from the sheet, and the printed continuous paper 1 is folded by the folding section 9.

FIG. 5 (b) is a detailed view of the buffer arm portion of FIG. 5 (a). The operation will be described in more detail with reference to FIG. 5B together with FIG. The continuous paper 1 is conveyed by the tractor 2 at a constant printing speed. The buffer arm 10 provided at the entrance of the fixing unit 6 has a structure that rotates when the continuous paper 1 is fed and pulled by the paper feed roller 8, and is pulled up by the tension of the spring 11 when there is no continuous paper 1. The paper feed roller 8 is driven by a motor as a power source to rotate, and the driven roller 82 is a leaf spring 8.
It is a structure in which the continuous paper 1 is conveyed by being pressed against the drive side roller by 1. The drive speed is set to a rotational speed that is several percent (4 to 7%) higher than that of the tractor 2, and the paper feed roller 8 and the paper always slip. The buffer arm 10 is kept in a state of being pressed and pushed down by adjusting the slip.

The pressurizing side of the paper feed roller 8 is of a cantilever leaf spring type, and a driven rotor 82 is suspended from the tip of the leaf spring 81 and the other is fixed. By adjusting the fixing position, the amount of deflection of the leaf spring 81 is changed to adjust the pressing force, and the plate spring 81 is fixed at a predetermined pressure for use.

A second example of the conventional printer device is, for example, as disclosed in Japanese Utility Model Laid-Open No. 3-38195, a paper feed roller is provided with a transmission torque limiting mechanism, and a pressure roller is provided along the circumferential direction. A technique is disclosed in which at least two sets are provided at distant positions to stabilize the roller pressure.

[0006]

In these conventional printer apparatuses, since the amount of pressure applied to the paper feed roller is constant, the amount of bending of the spring is reduced due to wear of the paper feed roller, and the amount of pressurization is reduced. It becomes impossible to carry it stably. In addition, it is necessary to periodically check and adjust the amount of pressurization, which requires maintenance.

[0007]

A printer device having a paper feed roller pressure adjusting mechanism of the present invention comprises a conveying means for conveying continuous paper, a measuring means for measuring the amount of paper tension during the continuous paper conveyance, and A paper pressing force adjusting means for adjusting the paper pressing force of the conveying means, and a control means for outputting the paper pressing force adjusting signal to the paper pressing force adjusting means according to the paper tension amount are provided.

Further, the printer device having the paper feed roller pressure adjusting mechanism of the present invention is characterized in that the carrying means is a paper feed roller for carrying the continuous paper at a constant speed.

Further, in the printer device having the paper feed roller pressure adjusting mechanism of the present invention, the measuring means is an arm that is in axial contact with the continuous paper by a spring force and a measuring means of the angle of the arm. With.

Further, in the printer device having the paper feed roller pressure adjusting mechanism of the present invention, the paper pressing force adjusting means is attached to one end of the leaf spring for suspending the pressure roller and the other end of the leaf spring. The block includes a block and a moving unit that moves the block in the bending direction of the leaf spring.

[0011]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, the present invention will be described with reference to the drawings. FIG. 1 is an overall view of a printer device according to an embodiment of the present invention, and FIG. 2 is a view for explaining input / output signals to a paper feed roller control unit. 3 is a partially enlarged view of the buffer arm sensor shown in FIG. 1, FIG. 3 (a) is a side view thereof, FIG. 3 (b) is a top view thereof, and FIG. 3 (c) is a view of the sensor. It is a figure which shows an example of a signal stage. 4 is a partially enlarged view of the paper feed roller pressure adjusting mechanism shown in FIG.
4A is a side view thereof, and FIG. 4B is a top view thereof.

Referring to FIG. 1, a printer apparatus having a paper feed roller pressure adjusting mechanism of this embodiment is a continuous paper 1
A continuous paper 1 including a paper feed roller 8 for conveying the paper at a constant speed, a buffer arm 10 that is in axial contact with the continuous paper 1 by a spring force, and a buffer arm sensor 12 that measures the angle of the buffer arm 10. Measuring means for measuring the amount of paper tension during conveyance, a leaf spring 81 suspending a pressing roller 82 at one end, a block 83 attached to the other end of the leaf spring 81, and a deflection direction of the block 83 for the block 83. The paper pressing roller adjusting means for adjusting the paper pressing force of the paper feeding roller 8 composed of the motor 87 that moves to the paper and the paper feeding roller control for outputting the paper pressing force adjusting signal to the paper pressing force adjusting means according to the amount of paper tension. And a part 13.

Further detailed description will be given with reference to FIGS. 2, 3 and 4 together with FIG. The continuous paper 1 is conveyed to the transfer portion 21 by the tractor 2 and is irradiated with the laser light 3 to the photosensitive member
The latent image is formed on the surface and the image visualized by the developing device 5 is transferred. The continuous paper 1 is again sent to the fixing unit 6 by the tractor 2. The fixing unit 6 is provided with a lamp unit 7 that fixes the toner with flash light energy. The paper feed roller 8 discharges the continuous paper 1 from the fixing unit 6, and folds the printed continuous paper 1 at the folding unit 9.

The buffer arm sensor 12 is provided at the entrance of the fixing unit 6. The shutter 121 attached to the tip of the rotary shaft is interlocked with the change in the angle of the buffer arm 10, and the shutter 1
Reference numeral 21 interrupts the photosensor 123 to signal the angle of the buffer arm 10. The signal of the photo sensor 123 changes in a plurality of steps according to the angle of the buffer arm 10. FIG. 3C shows signals in six stages depending on the states of the three photosensors 123. The paper feed roller pressure adjusting mechanism 80 suspends the roller 82 at the tip of the leaf spring 81,
The other is fixed to the block 83. Block 83
Is supported by a block guide 84, and is movable in the bending direction of the leaf spring 81. A tap hole is formed in the block guide 84, and a screw shaft 85 is joined to the block guide 84. The screw shaft 85 can be rotated by a motor 87 connected by a worm gear 86. The screw shaft 85 is supported by a bearing 88 and a flange 89 so as to move the block 83 by rotating. The paper feed roller control unit 13 inputs a signal from the buffer arm sensor 12 and outputs a command to the paper feed roller pressure adjusting mechanism 80.

Next, the operation will be described with reference to FIGS. 2, 3, and 4 together with FIG. When the normal or paper feed roller 8 is new, the pressure of the paper feed roller 8 is set to a predetermined pressure. With a predetermined pressure, the sinking amount of the buffer arm 10 is a predetermined amount. In this embodiment, the predetermined sink amount is set to 10 mm, and the sink amount of the buffer arm 10 is 0 to 3 mm, 3.1 to 6.0 mm, 6.1.
If it is divided into 9.0 mm, 9.1 to 11 mm, 11.1 to 14 mm and 14.1 mm or more, and the respective sinking amounts are referred to as ,,, and, respectively,
The predetermined amount will be referred to as the sink amount.

Since the peripheral speed of the driving-side paper feed roller 8 is always rotating faster than that of the continuous paper 1, it is worn by friction. Especially in the case of rollers using silicon rubber, B4
About 300,000 pages of paper are abraded by about 0.5 mm. Therefore, the amount of deflection of the driven side leaf spring 81 is reduced, and the frictional force is reduced. At this time, the sinking amount of the buffer arm 10 also decreases. When the sinking amount of the buffer arm 10 changes from to, the paper feed roller control unit 13 outputs a preset output signal to the paper feed roller pressure adjusting mechanism 80. The paper feed roller pressure adjusting mechanism 80 rotates the motor 87 to the pressure side. Rotation of motor 87 causes leaf spring 8
The deflection amount of 1 increases and the frictional force increases, and the buffer arm 1
0 begins to sink. When the buffer arm sensor 12 detects the sinking amount again, the motor 87 stops driving. In addition, when the amount of sink is not less than that (for example, when the frictional force of the paper feed roller 8 increases due to the temperature), the motor 87 can be reversed. As described above, the operation of adjusting the pressure of the paper feed roller 8 can be performed by the output of the buffer arm sensor 12.

[0017]

As described above, according to the present invention,
It is not necessary to periodically check and adjust the pressure of the paper feed roller by measuring the amount of paper tension during continuous paper conveyance and adjusting the paper pressing force of the continuous paper conveyance means according to the amount of paper tension.

[Brief description of drawings]

FIG. 1 is an overall view of an embodiment of the present invention.

FIG. 2 is a diagram illustrating input / output signals to / from a paper feed roller control unit according to this embodiment.

3 is a partially enlarged view of the buffer arm sensor shown in FIG. 1, FIG. 3 (a) is a side view thereof, and FIG.
Is a top view thereof, and FIG. 3C is a diagram showing an example of signal stages of the sensor.

4 is a partially enlarged view of the paper feed roller pressure adjusting mechanism shown in FIG. 1, and FIG. 4 (a) is a side view thereof.
(B) is the top view.

5A is an overall view showing a conventional example, and FIG.
FIG. 5B is a detailed view of the buffer arm portion of FIG.

[Explanation of symbols]

 1 Continuous Paper 2 Tractor 21 Transfer Part 3 Laser Light 4 Photoconductor 5 Developing Device 6 Fixing Part 7 Lamp Unit 8 Paper Feed Roller 80 Paper Feed Roller Pressure Adjusting Mechanism 81 Leaf Spring 82 Roller 83 Block 84 Block Guide 85 Screw Shaft 86 Worm Gear 87 Motor 88 Bearing 89 Flange 9 Stacker 10 Buffer arm 11 Spring 12 Buffer arm sensor 121 Shutter 123 Photo sensor 13 Paper feed roller control unit

Claims (4)

[Claims] 1. A conveying means for conveying continuous paper, a measuring means for measuring a paper tension amount during the continuous paper conveyance, a paper pressing force adjusting means for adjusting a paper pressing force of the conveying means, and the paper tension. A printer device having a paper feed roller pressure adjusting mechanism, comprising: a control unit that outputs the paper pressing force adjustment signal to the paper pressing force adjusting unit in accordance with a force amount. 2. The printer device having a paper feed roller pressure adjusting mechanism according to claim 1, wherein the carrying means is a paper feed roller that carries the continuous paper at a constant speed. 3. The paper feed according to claim 1, wherein the measuring means includes an arm that is in axial contact with the continuous paper by a spring force and is in contact with the continuous paper, and a measuring means for measuring an angle of the arm. A printer device having a roller pressure adjusting mechanism. 4. The sheet pressing force adjusting means includes a leaf spring for suspending a pressure roller at one end, a block attached to the other end of the leaf spring, and a movement for moving the block in a bending direction of the leaf spring. A printer device having a paper feed roller pressure adjusting mechanism according to claim 1, further comprising: