JPH04217537A - Adjusting mechanism for paper sucking force - Google Patents

Abstract

PURPOSE:To provide a paper sucking force adjusting mechanism which can always obtain good paper carrying performance when a blower power source is of either 50Hz or 60Hz with respect to a paper sucking force adjusting mechanism of a paper suction carry unit which is used in an electronic photographing recorder or the like such as a copy machine, a printer and a facsimile for sucking and carrying paper sheets. CONSTITUTION:A paper suction carry unit 15 comprises a sucking belt 41 for sucking and carrying paper sheets inside an outer console 52 and sucks the paper sheets on the sucking belt 41 and carries them by sucking the outer console 52 via a duct 54 by a blower 42 which uses an ac power source. An air hole 53 which is opened only when a power source is 60Hz is provided at least one of the outer console 52 and the duct 54, thereby making paper sucking force when the power source is 60Hz approximately equal to that of 50Hz.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a paper suction force adjustment mechanism for a paper suction/conveyance section used in electrophotographic recording devices such as copying machines, printers, and facsimile machines for suctioning and conveying paper.

[0002] In electrophotographic recording apparatuses, a method is often used in which paper is conveyed from a transfer section to a fixing section by suctioning the sheet to a suction belt of a paper suction conveyance section using a blower as a suction source. Alternating current is generally used as a power source for blowers.

0003

2. Description of the Related Art FIG. 3 is a perspective view showing the external appearance of this type of electrophotographic recording device, and FIG. 4 is a side view of the same.
It is composed of a main body locker 2 and a stacker locker 3. Figure 4
The double arrow line drawn in is the dividing part of both lockers. In addition, the part surrounded by the arrow line in FIG. We are prepared. Note that 10 is a power control unit, 11 is a processing unit such as an interface, 12 is an upper stacker, 13 is a lower stacker, and 14 is a tray.

An outline of the structure of the mechanism unit 4 is shown in FIG. 5, and a detailed structure of the printer section 8 is shown in FIG. In the figure, 15 is a standby section, 16 is a photosensitive drum, 17 is a paper suction conveyance section, 2
9 is a fixing device. Around the photosensitive drum 16, there are a pre-charger 18, an optical unit 19 for exposure, a developer 20, a pre-transfer static eliminator 21, a transfer charger 22, an AC separation charger 23, and a post-transfer static eliminator 23. An electric appliance 24 and a cleaner 25 are arranged.

[0005] Recording sheets are stored in an upper hopper 5, a middle hopper 6, and a lower cassette 7, and are selectively fed out by pick rollers 261, 262, and 263, respectively. The fed paper is separated by separation roller 2.
71 , 272 , and 273 prevent double feeding, and are sent to the standby section 15 through the paths shown by the chain lines, respectively. Reference numeral 28 denotes a feed roller for conveying paper provided in each path.

On the other hand, the photosensitive drum 16 rotates counterclockwise in FIGS. 5 and 6, and a toner image is formed on its surface in the following procedure. That is, the surface of the photosensitive drum 16 is first uniformly charged by the front charger 18, and then the surface of the photosensitive drum 16 is charged uniformly by the front charger 18.
9, an electrostatic latent image is formed by exposure in a predetermined pattern. This electrostatic latent image is developed by a developing device 20 to become a toner image. The pre-transfer static eliminator 21 irradiates the drum surface with red light to reduce the amount of charge of the toner on the drum surface to a certain level, thereby increasing efficiency in the next transfer section.

After that, the toner image advances to the transfer position (the position where the chargers 22 and 23 face the photosensitive drum), but as mentioned above, the paper sent to the standby section 15 is buffered and stopped there. The paper is sent to the transfer position in accordance with the rear drum speed, and the toner image is transferred onto the paper by the transfer charger 22. The AC separation charger 23 discharges an AC high voltage with a relatively high frequency onto the paper to reduce the amount of charge, thereby making the paper easier to peel off from the drum. After the transfer has been completed, the surface of the photosensitive drum 16 is removed by a post-transfer static eliminator 2.
4 and cleaned by a cleaner 25.

[0008] The paper onto which the toner image has been transferred is sent to a fixing device 29 by the paper suction conveyance section 17, where the toner image is fixed. In the case of one-sided recording, the selector valve 30 is positioned as shown by the dotted line in FIG.
is discharged. The high voltage power supply 32 in FIGS. 5 and 6 is the front charger 1
8, development bias, transfer charger 22, AC separation charger 2
This is to supply high pressure to 3.

In the case of double-sided recording, the selector valve 30 is
The paper is guided by the selector valve 30 and sent to the paper reversing mechanism section 33. The paper sent to the paper reversing mechanism section 33 is conveyed to the buffer section 36 by a scraping roller 34 and a lower scraping pinch roller 35, as shown in detail in FIG. The reversing pinch roller 37 presses the paper by turning on a reverse magnet (not shown) and temporarily stops the paper running. Note that when the reverse magnet is OFF, there is a gap of about 1 mm between the reversing pinch roller 37 and the reversing roller 38. The trailing edge a of the sheet held in the buffer section 36 is scraped up by the scraping roller 34, and after the reversing pinch roller 37 is released from operation, the trailing edge a of the sheet is conveyed toward the drum again by the scraping upper pinch roller 39 and the scraping roller 34.

FIG. 8 shows a paper conveyance system within the printer section 8. The paper conveyed by both rollers 34 and 39 is conveyed in the direction of arrow A and sent to the standby section 15. In this state, the paper is inverted, and then recording is performed on the back side using the same procedure as described above. When the paper on which the reverse side recording has been completed leaves the fixing device 18, the selector valve 30 has returned to the state indicated by the dotted line in FIG. 5, and the paper is carried out to the stacker locker 3.

FIG. 9 shows an outline of the structure of a conventional paper suction conveyance section used in a recording apparatus having the above-mentioned configuration and operation. In the figure, 41 is a suction belt running in the direction of the arrow;
2 is an air separation blower driven by an AC power source.

The suction belt 41 has holes at regular intervals, and the suction force of the blower 42 sucks air through the holes to suction and convey the paper 100. Toner mixed into the air sucked through the holes in the belt is removed by an air filter 43. Clogging of the air filter 43 is detected using the pressure difference between before and after the filter, which is detected by the pressure sensor 44. Also, blower 4
The rotation of No. 2 is detected by a pressure sensor 46 that detects the difference between the pressure inside the hose 45 and the atmospheric pressure.

[0013]

[Problem to be solved by the invention] As mentioned above, the blower 4
When the second power source is an alternating current, the rotation speed is different between 50 Hz and 60 Hz, so the suction force is different. Therefore, even in the paper suction conveyance section using this blower, the suction force for the paper differs. If the suction power is too weak, paper cannot be suctioned and transported properly, but if the suction power is too strong,
The load on the belt that performs suction conveyance increases (in the case of 60 Hz, the rotation speed of the blower 42 is high, so the static pressure inside the suction unit is high, and a large torque is required to drive the suction belt 41).
This may cause the belt to slip or the motor to malfunction. Therefore, depending on the device, 5
It is necessary to take measures to make the paper suction force almost the same at 0 Hz and 60 Hz.

[0014] In the present invention, the blower power supply is 50Hz, 60H.
It is an object of the present invention to provide a paper suction force adjustment mechanism that can always obtain good paper conveyance performance in any case of z.

[0015]

[Means for Solving the Problems] In order to achieve the above-mentioned object, the present invention includes a suction belt for sucking and conveying paper inside an outer envelope, and a blower using an AC power source causes a duct inside the envelope. In the paper suction conveyance unit in which the paper is attracted to the suction belt by suction through the suction belt, an air hole that is opened only when the power supply is 60Hz is provided in at least one of the envelope or the duct,
The structure is characterized in that the paper suction force when the frequency is z is approximately equal to that when the frequency is 50 Hz.

[0016]

[Operation] The air hole is opened only when the blower power source is 60 Hz, and is closed when the blower power source is 50 Hz. Therefore, the paper suction force to the suction belt at 60 Hz is less than the conventional one, and is almost equal to that at 50 Hz. That is, good paper conveyance performance can always be obtained.

[0017]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to FIGS. 1 and 2.

FIG. 1 is a side view showing the external appearance of the paper suction conveyance section 51 of this example, and 52 is an outer shell that covers the periphery of the suction belt 41 (excluding the front, rear, and bottom surfaces). The outer enclosure 52 includes an air hole 53 of a predetermined size, and a blower 4 whose power source is AC.
2 through a duct 54 so that the inside can be sucked. In the middle of the duct 54, although not shown, a filter similar to the conventional one is provided. Further, the outer enclosure 52 is provided with an air volume adjusting plate 56 having a long hole 55 extending left and right. The air volume adjusting plate 56 is movable in the left-right direction and is fixed by a bolt 57 inserted into the elongated hole 55. The air volume adjustment plate 56, the bolt 57, and the air hole 53 constitute a paper suction force adjustment mechanism 58.

The operation of the paper suction force adjustment mechanism 58 will be explained with reference to FIG. 2 as follows.

When the AC power source of the blower 40 is 60 Hz, the air volume adjusting plate 56 is moved all the way to the left to fully open the air hole 53, as shown in FIG. 2(A). Also, Proa 40
When the AC power source is 50 Hz, the air hole 53 is closed by moving the air volume adjustment plate 56 all the way to the right as shown in FIG. 2(B). Note that the air volume adjustment plates 56 at each position are fixed by tightening bolts 57.

[0021] In this way, only in the case of 60Hz, the air hole 53
is opened, and outside air flows in through this air hole 53 when the fan 42 takes in air, so the outer enclosure 5
The static pressure inside 2 becomes lower and becomes almost equal to the case of 50 Hz when the air hole 53 is open.

In the above description, an example has been described in which the outer envelope 52 is provided with an air hole and an air volume adjustment plate, but the duct 54 may be provided with an air hole and an air volume adjustment plate, and the same effect can be obtained in this case as well. Furthermore, in the above description, an example has been described in which the air hole is closed by moving the air volume adjustment plate, but the air hole may be closed with a screw-in lid.

[0023]

Effects of the Invention As described above, according to the present invention, by opening the air hole only when the frequency is 60Hz,
The static pressure inside the envelope can be made almost equal at z and 60 Hz, and good paper conveyance performance can always be obtained.

[Brief explanation of the drawing]

FIG. 1 is a side view showing the appearance of a paper suction conveyance section according to an embodiment of the present invention.

FIG. 2 is an explanatory diagram of the operation of the paper suction force adjustment mechanism according to the embodiment of the present invention, in which FIG. 2(A) shows the case at 60 Hz, and FIG. 2(B) shows the case at 50 Hz.

FIG. 3 is a perspective view showing the appearance of an electrophotographic recording device.

FIG. 4 is a side view showing the appearance of the electrophotographic recording device.

FIG. 5 is a side view showing an outline of the structure of the mechanism unit.

FIG. 6 is a detailed view of the main part of FIG. 5;

FIG. 7 is a side view showing details of the paper reversing mechanism section.

FIG. 8 is an explanatory diagram of a paper conveyance system within the printer section.

FIG. 9 is a side view showing an outline of the structure of a conventional paper suction conveyance section.

[Explanation of symbols]

41 Suction belt 42 Blower 51 Paper suction transport section 52 Envelope 53 Wind hole 54 Duct 56 Air volume adjustment plate 58 Paper suction force adjustment mechanism

Claims (1)

[Claims] [Claim 1] Suction belt (41) for sucking and conveying paper
is provided in the outer enclosure (52), and a duct (5
4) In the paper suction conveyance unit where the paper is attracted to the suction belt (41) by suction through the suction belt (41), an air hole 53 that is opened only when the power is 60Hz is connected to the outer body (52) or the duct. (54), and the paper suction force is 50Hz when it is 60Hz.
A paper suction force adjustment mechanism characterized in that the paper suction force is made to be approximately equal to that when .