JPH05116809A - Pneumatic paper feeder - Google Patents

Abstract

(57) [Summary] (Correction) [Purpose] The target value can be accurately matched by simply and finely adjusting the air pressure for paper feeding using a digital method.
Reduce work time and streamline maintenance after completion. [Structure] A fan that blows air onto a laminated sheet and sucks air is rotationally driven by a continuously variable speed motor 9. This motor 9 is used as feedback speed control means 2
1. The driving unit 22 accurately holds and drives at the set rotation speed. In that case, the rotation speed can be set digitally by key operation, and the set speed value is held by the storage means 33 until the next adjustment instruction is given.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention is installed in a copying machine such as a copying machine and is capable of feeding the uppermost sheets one by one from a laminated sheet by blowing and sucking air. Regarding

[0002]

2. Description of the Related Art A conventional pneumatic type sheet feeding device used for electronic equipment is a stacking device that uses a traveling suction belt to blow air onto a front end side of a laminated sheet, that is, an upper part of a leading end side of the sheet to be blown to separate sheets. Generally, a structure is adopted in which air is sucked onto the upper surface of the sheet to separate the copy sheets one by one and feed them to the copying section.

In this case, an air pressure measuring device such as a pitot tube is used in order to prevent feeding error due to small blown air pressure (positive pressure) and suction air pressure (negative pressure) during paper feeding, and conversely double feeding due to large air pressure. By measuring the air pressure, the clearance between the exhaust duct and the intake duct was adjusted to adjust the air pressure, and the pressure was adjusted.

[0004]

This adjusting operation of the air pressure is a very difficult work and can only be adjusted to confirm that it is within a certain pressure range. Since there is a risk that paper will not be fed normally, means such as filling the gap in the duct with a filler to finely adjust the opening area is required, and the work and the loss of time and labor are not small. There is a problem that increases the product cost.

It is an object of the present invention that this air pressure adjustment can be finely performed by a simple digital operation, and the air pressure setting can be exactly matched with a target value, thereby significantly reducing the working time for manufacturing. It is an object of the present invention to provide a pneumatic feeding device that can be shortened and the maintenance after completion can be rationalized.

[0006]

DISCLOSURE OF THE INVENTION The present invention is a pneumatic type sheet feeding device for feeding the uppermost sheet by blowing air to the upper part of the front end side of a laminated sheet and sucking air to the upper surface thereof. Variable speed motor that rotationally drives the fan and air suction fan individually or collectively, a speed detector that detects the rotational speed of the continuously variable motor, and the key operation of the rotational speed of the continuously variable motor. The rotational speed setting means that can be set digitally by means of, the storage means that stores and holds the rotational speed set by the rotational speed setting means, the set rotational speed read from the storage means, and the speed detector detect And a feedback speed control means for outputting a speed control command signal corresponding to the set rotation speed, and power to the continuously variable speed motor in response to the speed control command signal. Empty pressure system sheet feeding apparatus comprising a drive means for force.

[0007]

According to the present invention, the rotation speed setting means, for example, a key such as a driving operation key is operated to operate the fan for blowing air and / or the fan for sucking air in the production process and at the time of maintenance in the market. The rotation speed of the continuously variable motor is set, and in that case, the air pressure in each duct is measured by the air pressure measuring device.

With respect to adjusting the number of revolutions so that the most appropriate air pressure can be obtained for feeding the sheet, since the rotational speed setting is operated by a digital value, it can be performed easily, quickly and accurately. Moreover, since the proper value once set is held by the storage means and the feedback speed is controlled, the air pressure does not fluctuate during use, and it is also excellent in terms of handling ease and reliability. There is. Also, the operation for readjustment can be easily performed by key operation. In addition, the rotation speed setting means,
The object can be sufficiently achieved by providing it in a place such as a control box which is convenient for the inspection operation by the service person and cannot be easily operated by the customer.

[0009]

1 is a vertical cross-sectional view showing the schematic construction of a paper feeding apparatus according to an embodiment of the present invention.

Laminated sheet 1 in which a plurality of sheets are stacked
Is placed on a sheet supply table 2 made of an elastic spring or the like, and the upper limit switch 3 is arranged so as to abut on the rear portion of the upper surface of the laminated sheet 1. This upper limit switch 3
Is a switch for detecting that the upper surface of the uppermost laminated sheet 1 is at the height position of the upper limit switch 3.

A suction belt 4 is arranged above the sheet supply table 2 as a conveying means for sucking and conveying the sheet. An opening of an intake duct 5 hung from above the suction belt 4 faces the middle part of the suction belt 4, and the intake duct 5 is connected to an intake fan 7 which is one component of the fan device 6.

On the front end side of the laminated sheet 1 below the suction belt 4, that is, on the side where the sheet is sent out by the suction belt 4, air is blown toward the upper front end of the laminated sheet 1 and is sucked by the suction belt 4. An air supply nozzle 11 for separating the uppermost sheet and the remaining sheets is arranged. This air supply nozzle 11
Is connected to an exhaust port 8a of an exhaust fan 8 which is one component of the fan device 6 via an exhaust duct 12.

A sheet feeding path 13 for feeding the fed sheet into the copying machine is disposed on the sheet feeding side of the suction belt 4, and a feeding roller 14a for feeding the sheet is provided in the middle of the sheet feeding path 13. 14b is provided.

The intake fan 7 and the exhaust fan 8 of the fan unit 6 are individually covered with the cases 7b and 8b, and are coaxially arranged via a partition wall which is a part of the cases 7b and 8b. It is connected to an output shaft 9a of a continuously variable speed motor realized by one DC servo motor 9.

The intake fan 7 and the exhaust fan 8 are
As shown in FIG. 2, a plurality of blades 16 are radially arranged on a circular bottom plate 15, and a donut-shaped upper plate 1 is provided thereon.
The body of the sandwich structure is layered on the case 7
It is constituted by being surrounded by b and 8b.

As shown in the perspective view of FIG. 3, the suction belt 4 is formed by winding a pair of endless belts 19 between pulleys 18a and 18b at intervals in the axial direction of the pulleys 18a and 18b. Yes, those endless belts 1
A large number of vent holes 19a that are inserted in the thickness direction are formed in a dispersed manner in 9 and the suction force of the intake duct 5 is guided to the endless belt 19 running below through the vent holes 19a. ..

FIG. 4 is a circuit diagram showing the connection configuration of the DC servomotor 9 and each circuit for controlling the drive and rotation of the motor.

The speed switching circuit 20 includes a DC servo motor 9
It is a circuit that outputs a rotation speed switching command. The speed control circuit 21 is a circuit that controls the rotation speed of the DC servomotor 9 according to the reference clock signal 31 provided from the speed switching circuit 20. The drive circuit 22 is a circuit that drives the DC servo motor 9 according to a control signal output from the speed control circuit 21. The inverter 23 is a circuit that converts a part of the control signal output from the speed control circuit 21 into a control signal corresponding to the energization time and supplies the control signal to the drive circuit 22.

The speed control circuit 21 detects D detected by a speed detector realized by the rotary encoder 24.
A speed discriminator 2 for detecting a speed error by comparing the signal RE of the C servo motor 9 with a reference clock signal 31.
5. A charge pump circuit 26 for converting the speed error detected by the speed discriminator 25 into a speed control voltage, an amplifier 27, and a PWM circuit 2 for pulse-width modulating the speed control voltage obtained by the charge pump circuit 26.
8, and the U phase, V phase, based on the pulse width modulation signal obtained by the PWM circuit 28 and the rotation phase of the DC servomotor 9 detected by the position sensor 29.
It is configured by a distribution circuit 30 which distributes and outputs a control signal corresponding to each W-phase motor coil. The reference clock signal 31 outputs a constant value at the frequency stored in the RAM, which is the storage unit 33 connected to the CPU 32. This frequency can be input by operating the keys on the operation panel 34, and is adjusted at the time of service / production process. At the end of the adjustment, the last input (set) frequency is stored in the RAM, and this value becomes the frequency of the reference clock signal 31 until the next adjustment work is started. In this case, the speed data stored in the RAM 33 is backed up by the battery 35 so as not to be erased even when the power is turned off.

The operation of the paper feeding device will be described with reference to FIG.

The outline of the operation is as follows. DC
By the rotational drive of the servo motor 9, the intake fan 7 and the exhaust fan 8 rotate, and air flows in the intake fan 7 as indicated by an arrow a and in the exhaust fan 8 as an arrow b. As a result, the air pressure in the intake duct 5 drops, and the uppermost sheet of the laminated sheets 1 is sucked by the suction belt 4. At this time, the air sent from the exhaust fan 8 through the exhaust duct 12 is blown from the air supply nozzle 11 to the front end side of the laminated sheet 1, whereby the uppermost sheet is lifted and the sheet to the suction belt 4 is lifted. Is smoothly absorbed.

The sheet adsorbed on the suction belt 4 is sent to the paper feed path 13 by driving the suction belt 4, and is fed by the transport rollers 14a and 14b.
Is sent to the inside of the copying machine.

As explained above, for example, spraying,
Although the suction is performed by one variable speed motor, it is of course possible to perform the suction by two individually connected variable speed motors. In that case, the control circuit shown in FIG. It is necessary to provide.

At the time of production process or service in the market, an air pressure measuring instrument is inserted near the air supply nozzle 11 or the intake duct 5, and the key of the operation panel 34 is used to
The rotation speed of the C servo motor 9 is set and adjusted so that the required desired air pressure is maintained.

Data from the operation panel 34 is stored in the CPU 32.
Is temporarily stored in the RAM 33 and written in the RAM 33, and is stored until the next data is updated.

In the paper feeding operation, the servo motor 9 is rotated / stopped by the start / stop signal from the CPU 32, and at the same time, the reference clock signal 31 is generated based on the data stored in the RAM 33.
The rotation speed of the servo motor 9 is controlled to the set rotation speed.

[0027]

As described above, according to the present invention, the speed control of the continuously variable speed motor for rotationally driving the air blowing fan and the air suction fan is performed by the feedback control method. High-precision speed control that matches the speed can be performed, and the speed setting can be finely adjusted digitally by operating keys such as the numeric keypad, and the setting can be matched exactly to the target value in a short time, It is easy to handle, and speed adjustment, that is, air pressure adjustment can be performed with high precision and speed.

[Brief description of drawings]

FIG. 1 is a vertical sectional view showing a schematic configuration of an embodiment of the present invention.

FIG. 2 is a perspective view of a rotor in the fan device 6 shown in FIG.

3 is a perspective view of the suction belt 4 shown in FIG. 1. FIG.

FIG. 4 is a block diagram showing an electrical configuration for controlling the speed of the fan device 6 shown in FIG.

[Explanation of symbols]

 1 Laminated Sheet 7 Intake Fan 8 Exhaust Fan 9 DC Servo Motor 20 Speed Switching Circuit 21 Speed Control Circuit 22 Drive Circuit 24 Rotary Encoder 33 RAM 34 Operation Panel

Claims (1)

[Claims] 1. A pneumatic type sheet feeding device for feeding the uppermost sheet by blowing air to the upper part of the front end side of the laminated sheet and sucking air to the upper surface of the laminated sheet, comprising: an air blowing fan and an air sucking fan. A continuously variable speed motor that rotates individually or collectively, a speed detector that detects the rotational speed of the continuously variable speed motor, and the rotational speed of the continuously variable motor can be set digitally by key operation. The rotation speed setting means, the storage means for storing and holding the rotation speed set by the rotation speed setting means, the set rotation speed read from the storage means and the rotation speed detected by the speed detector are compared. Feedback speed control means for outputting a speed control command signal corresponding to the set rotation speed, and driving means for outputting electric power to the continuously variable speed motor in response to the speed control command signal. Pneumatic feeding device