JPH10305635A - Static eliminator for print sheet - Google Patents

Abstract

PROBLEM TO BE SOLVED: To ensure stabilized neutralization effect even for different environmental conditions, e.g. ambient temperature or humidity, of a printer. SOLUTION: The static eliminator comprises a neutralization brush 10 touching a print sheet, a rack 13 supporting the neutralization brush, a motor 14 provided with a gear 15 to be fitted with the rack 13, a sensor 16 for measuring the charging quantity of static electricity on the print sheet disposed in front of the neutralization brush 10 in the advancing direction of the print sheet, and a controller 12 for controlling the position of the neutralization brush 10 to minimize the charging quantity of static electricity measured by the sensor 16 by rotating the motor 14 forward or reversely.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an improvement in a static electricity removing device for removing static electricity generated by high-speed continuous paper transport of a printer or the like.

[0002]

2. Description of the Related Art Generally, in an electrophotographic printer,
Since the toner image formed on the photosensitive drum is transferred onto the paper and the printing paper is charged during the transfer, the static elimination is performed by using a static eliminator to remove the static electricity.
FIG. 4 shows an example of the above static electricity removing device. In the figure, the whole shows a printing apparatus using continuous paper. The printing apparatus stores a printing paper 2 in a printing paper supply unit 1 and is driven by a belt 8 from a motor 8 to a paper transport roller 4. Power is being transmitted. The conveying force is transmitted to the sheet by the sheet conveying roller 4 and a pinch roller 4 a disposed on the opposite side of the sheet conveying roller 4 via the sheet 2. The printing unit 7 prints on the paper 2 in pairs with the drum 5. The fixing unit 9 is arranged behind the printing unit 7. The paper transport path is secured by the guide 3 over the entire transport path of the paper 2. The paper 2 transported after printing is stored in the printing paper storage unit 11, but before that,
The static electricity removing brush 10 is fixed at a fixed distance from the paper 2 to remove static electricity from the paper 2.

Next, the operation will be described. The printing paper 2 is carried out of the paper storage unit 1, passes between the guides 3, receives a driving force by friction from the paper transport roller 4 and the pinch roller 4 a, and is transported to the printing unit 7 and the drum 5. In the printing unit 7 and the drum 5, the paper 2 on which the printing pattern has been applied by the toner is conveyed to the fixing unit 9 and heated to melt the toner to fix the printing pattern. Thereafter, the printed paper 2 is conveyed between the guides 3 and the static electricity removing brush 10 removes the static electricity charged on the paper 2. Thereafter, the paper is further conveyed, passes between the paper guides 3, and is folded and stored in the print paper storage unit 11.

[0004]

Since the conventional static eliminator for printing paper is constructed as described above, the amount of charge on the paper depends on environmental conditions such as temperature and humidity around the printing apparatus. The distance between the charge-removing brush and the paper, which has the highest charge-removing effect, differs depending on the amount of charge, and static electricity cannot be removed efficiently. There was a problem that it did not fold well.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems, and an object of the present invention is to provide a static electricity removing device for printing paper which can obtain a stable static electricity removing effect even when the use environment of the printing device is different. Aim.

[0006]

According to the present invention, there is provided an apparatus for removing static electricity from a printing sheet, comprising: a removing brush arranged to face a printing sheet to be conveyed so that the leading end thereof contacts the rack; and a rack supporting the removing brush. A motor provided with a gear that fits with the rack, a sensor provided at a position ahead of the disposition position of the static elimination brush with respect to the traveling direction of the printing paper, and configured to measure an electrostatic charge amount of the printing paper; A control device is provided for controlling the position of the neutralizing brush by rotating the motor forward and reverse so as to minimize the amount of electrostatic charge measured by the sensor.

[0007]

BEST MODE FOR CARRYING OUT THE INVENTION

Embodiment 1 FIG. Hereinafter, an embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a side view showing a printing apparatus according to an embodiment of the present invention. In FIG. 1, 1
A printing paper supply unit stores printing paper 2 which is a continuous paper. Reference numeral 3 denotes a guide for transporting the printing paper 2, and a paper transport path by the guide 3 is formed over the entire printing apparatus. Reference numeral 4 denotes a paper transport roller to which a driving force is transmitted from a motor 8 by a belt 6. The print paper 2 is pinched by a pinch roller 4a provided corresponding to the paper transport roller 4 to thereby print the print paper 2. The conveying force is transmitted to Reference numeral 5 denotes a drum for forming characters, images, and the like, which are print patterns, using toner. The characters, images, and the like formed by the printing unit 7 are transferred to the printing paper 2 to perform printing on the surface of the printing paper 2.

Reference numeral 9 denotes a fixing unit 9 that heats the printing paper 2 conveyed from the printing unit 7 to melt the toner and fix the printing pattern. The printing paper 2 transported after the fixing is stored in the printing paper storage unit 11, and a static elimination brush 10 is provided to remove static electricity charged on the printing paper 2. The neutralizing brush 10 has a printing paper 2 at the tip of the brush.
And plays a role of releasing static electricity charged on the surface of the printing paper 2. 13 is a static elimination brush
A gear supporting the rack 10
The rack 13 moves forward and backward by the forward or reverse rotation of the motor 14 to which the is attached, and the neutralizing brush 10 fixed to the rack 13 approaches or separates from the printing paper 2.

Generally, the distance at which the neutralizing brush 10 slightly touches the printing paper 2 is set as the position where the maximum neutralizing effect is obtained. Is known to increase. 16
Is a sensor for measuring the amount of electrostatic charge, a signal of the measurement result is sent to the control device 12, and the control signal output from the control device 12 causes the motor 14 to rotate forward and reverse to measure the electrostatic charge amount. The position of the neutralizing brush is controlled so as to minimize the amount. Above neutralization brush
A static eliminator is constituted by the motor 14, the sensor 16 and the control device 12 to which the rack 13, the gear 13, and the gear 15 are attached.

Next, the operation of this device will be described.
The printing paper 2 is carried out of the paper storage unit 1, passes between the guides 3, receives a driving force by friction from the paper transport roller 4 and the pinch roller 4 a, and is transported to the printing unit 7 and the drum 5. In the printing unit 7 and the drum 5,
The paper 2 onto which the print pattern has been transferred by the toner is conveyed to the fixing unit 9 and is heated to melt the toner, thereby fixing the print pattern. Thereafter, the printing paper 2 on which printing has been completed by fixing is conveyed between the guides 3, and the static electricity charged on the printing paper 2 is removed to some extent by the neutralization brush 10. Thereafter, the paper is further conveyed, passes between the paper guides 3, and is stored in the print paper storage unit 11. Before this storage, the sensor 16 detects the amount of electrostatic charge on the surface of the printing paper 2 and transmits the detected amount to the control device 12, and the control device 12 rotates the motor 14 forward and reverse according to the amount of charge. The neutralizing brush 10 is driven via the gear 15 and the rack 13 to control the distance between the printing paper 2 and the neutralizing brush 10 so that the charge amount is minimized.

Therefore, even if environmental conditions such as temperature and humidity around the printing device change, the state of friction between the leading end of the neutralizing brush 10 and the surface of the printing paper 2 changes. It is possible to maintain an optimal static elimination state. Further, even when the tip of the neutralization brush 10 is shortened due to wear, the control device 12 controls the neutralization brush 10.
Is controlled so that the leading end of the printing paper 2 approaches the surface of the printing paper 2, so that the optimum distance can always be maintained.

In FIG. 1, a gear 15 is provided on a motor 14 to show the basic principle, and a rack 13 is directly connected to the gear 15. By providing a plurality of gears between them, fine adjustment is possible if necessary.

FIG. 2 is a detailed view of the assembly of the static elimination brush 10 and the like. The neutralization brush 10 is arranged to face the printing paper 2 and is supported on the left and right by rails 17a and 17b. Further, the rails 17a and 17b are fixed to the printing paper storage unit 11 by a rail support 18a and a rail support 18b. A rack 13 is fixed to a central portion of the charge removing brush 10, and the rack 13 and a gear 15 are engaged with each other. The gear 15 is press-fitted into a shaft of a motor 14. The motor 14 is connected to the printing paper storage 11
And are fixed on the same housing. A sensor 16 for measuring the amount of electrostatic charge is also arranged opposite the printing paper 2, and is fixed on the same housing as the printing paper storage unit 11 by a sensor support 20. The sensor 16 and the motor 14 are
The cable 21 is connected to the control unit 12. The drive motor is driven by the current pulse sent from the control unit 12.
14 rotates, and the rotation is transmitted to the static elimination brush 10 via the gear 15 and the rack 13, and the static elimination brush 10
The operation is performed along 17a and 17b, and the printing paper 2 is
Perform an approaching or moving away action.

By maintaining the surface of the printing paper 2 in an optimally neutralized state as described above, the static electricity of the paper can be suppressed, and the paper can be stuck on a guide or the like and cannot be easily folded in the paper storage after printing. Trouble can be prevented.

FIG. 3 shows the inside of the control unit 12. The analog signal of the charge amount from the sensor 16 is A / D
The signal is sent to the conversion unit 22, converted into a digital signal, and sent to the arithmetic unit 23. In the arithmetic unit 23, when the charge amount increases from the previous state due to the magnitude of the numerical value of the digital signal, a pulse for operating the motor 14 to rotate in the opposite direction to the previous feed direction is sent to the motor driver 24. . Further, when the charge amount decreases from the previous state, a pulse for operating the motor to rotate in the same direction as the previous feed direction is transmitted to the motor driver 24.
Send to The motor driver 24 sends a current pulse to the motor 14 for securing a predetermined movement amount.

In the first embodiment, a pulse motor is used as the motor 14, but it is needless to say that the control can be performed by using an analog motor.

[0017]

As described above, according to the present invention, the distance between the discharging brush and the printing paper is controlled so that the charge amount of the printing paper is minimized. Even if conditions such as humidity or abrasion of the static elimination brush change, there is an effect that a stable static elimination effect can be obtained.

[Brief description of the drawings]

FIG. 1 is a configuration diagram showing a printing apparatus using a static electricity removing device according to a first embodiment of the present invention.

FIG. 2 is a mounting diagram showing the static electricity removing device according to the first embodiment of the present invention.

FIG. 3 is a block diagram showing a control device according to the first embodiment of the present invention.

FIG. 4 is a configuration diagram showing a printing apparatus using a conventional static electricity removing device.

[Explanation of symbols]

10 static elimination brush, 12 controller, 13 rack, 1
4 motors, 15 gears, 16 sensors.

Claims (1)

[Claims] 1. A static elimination brush, which is disposed so that the leading end thereof is in contact with a conveyed printing paper, a rack for supporting the static elimination brush, a motor provided with a gear fitted with the rack, and the static elimination A sensor provided at a position ahead of the brush arrangement position with respect to the traveling direction of the printing paper, for measuring an electrostatic charging amount of the printing paper; and the motor so as to minimize the electrostatic charging amount measured by the sensor. A static electricity elimination device for a printing paper, comprising a control device for controlling the position of the static elimination brush by rotating the roller forward and reverse.