JPH052291A - Image forming device - Google Patents

Abstract

PURPOSE:To provide an image forming device in which a creeping distance is sufficiently secured at the small stroke of a switching mechanism. CONSTITUTION:This image forming device is constituted so that either mode can be selected out of a 1st mode for copying from a positive original picture to a positive image and a 2nd mode for copying from a negative original picture to a positive image by bisecting and constituting a device main body of two machine bodies which are freely opened and closed, and loading/unloading and exchanging a process cartridge 14 provided with a developing device with respect to either machine body. This device, is provided with, as a feature, a switching means for switching the mode so as to be fitted for the process cartridge by interlocking with loading the process cartridge 14 when two machine bodies are opened, and a switching contact parts 26 and 27 which are switched by the switching means by interlocking with the action for closing two machine bodies.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image forming apparatus for switching a charging high voltage in accordance with a copy image forming process.

[0002]

2. Description of the Related Art Conventionally, like reader printers,
An image forming apparatus having an optical mechanism unit for enlarging and projecting image information recorded on a microscopic film or the like on a reading screen and a printer mechanism unit for projecting on a photoconductor and outputting a copied image is a printer mechanism. The inside of the device can be opened for replenishment of the developer to the parts, removal and removal of jammed copy paper, and other maintenance, inspection, and repair work inside the machine.

Further, in such a reader printer, a positive copy image from a negative film (hereinafter referred to as a negative / positive image) and a positive copy image from a positive film (hereinafter referred to as a positive / positive image) are provided. There are two types of copy image forming processes to be created (hereinafter referred to as a copy process) that can be selected. In such a case, when the copy process is selected, the high voltage applied to the charged portion is set to 2 above.
The switching is made according to the type of copying process.

[0004]

However, in an image forming apparatus capable of switching between two types of copying processes as described above, switching of a high voltage is performed electrically by using a relay, so that the cost is high. There is a drawback that the device becomes large.

On the other hand, even in the case of mechanical switching, a high voltage is applied to the contacts so that a sufficient creeping distance is secured, so a large stroke is required for switching the contacts, and the apparatus or process cartridge becomes large. There was a drawback.

Further, since the high-voltage transformer for supplying the high voltage is disposed near the switching contact (optical mechanism section), the high-voltage cable connecting the high-voltage transformer and the charging portion becomes long, which impairs safety. Not only did it cause noise to other signal lines.

The present invention is intended to solve the above problems, and an object of the present invention is to provide an image forming apparatus capable of sufficiently securing a creepage distance by operating a small stroke of a switching mechanism.

[0008]

In order to achieve the above object, according to the present invention, a main body of an apparatus is divided into two bodies which can be opened and closed, and a process cartridge equipped with a developing device is attached to and detached from one of the bodies. In the image forming apparatus configured so that either one of the first mode for copying a positive original image to a positive image and the second mode for copying a negative original image to a positive image can be selected, At this time, a switching means for switching the mode according to each process cartridge in association with the mounting of the process cartridge and a switching contact for switching by the switching means in conjunction with the closing operation of the two machines are provided.

Further, the invention is characterized in that there are a plurality of the switching contacts, and the plurality of switching contacts are simultaneously connected.

Further, the switching contact is separated when the two bodies are opened.

[0011]

[Function] By exchanging the process cartridge for obtaining a negative / positive image and the process cartridge for obtaining a positive / positive image, the voltage applied corresponding to the copying process depending on the presence or absence of a protrusion provided only on one of the process cartridges. The switching mechanism provided to switch between is switched in conjunction with the insertion of the process cartridge,
Next, the switching contact is switched by the switching mechanism in conjunction with the operation of closing the optical mechanism unit and the printer mechanism unit.

[0012]

EXAMPLES Examples of the present invention will be described in detail below. Figure 2
2 shows a schematic configuration of a reader printer which is an image forming apparatus according to the present invention. First, a reader printer will be described. An optical mechanism unit 1 for selectively forming an image frame of a microfilm F as an information recording medium on a screen 8 or a photoconductor 4.
2 and a printer mechanism 13 for obtaining a duplicate of a desired image as an image forming apparatus.

The optical mechanism section 12 is provided with a light source 1 for film illumination, and a light beam from the light source 1 for film illumination is applied to the microfilm F via a condenser lens 2 and a field lens 3 to generate a micro light. The image light transmitted through the film F is projected onto the projection lens 5 and the mirror 6,
It is projected on the screen 8 via 7. The image light of the microfilm F is also projected onto the photosensitive drum 4 via the scanning type mirrors 10 and 11.

Reference numeral 13 denotes a printer mechanism section. The printer mechanism section 13 records an image by an electrophotographic process by operating a print button (not shown), and the photosensitive drum 4 is incorporated therein. A process cartridge 14 is provided. Process cartridge 1
As shown in FIG. 3, reference numeral 4 designates the printer mechanism unit 13 and the optical mechanism unit 1.
By opening from 2, the optical mechanism 12 can be inserted and removed in the front direction. In the following, 19 is a copy paper cassette, 20 is a paper feed roller, 21 is a register roller, 22 is a fixing roller, and 23 is a high voltage transformer.

FIG. 4 is a detailed view of the main part around the process cartridge 14 of FIG. 2, in which the primary charger 15, the developing device 16 and the cleaner 20 are integrally or detachably mounted. Has been. On the other hand, in the printer mechanism unit 13, a transfer guide 17 and a transfer charger 1 are provided below the cartridge 14 along the conveyance path of the sheet P.
8, a charge eliminating needle 19 is provided. In addition, as shown in the figure, the high voltage transformer 23, the primary charger 15, the developing device 16,
The transfer charger 18 and the charge elimination needle 19 are connected by a cable so that a high voltage is applied.

The connection between the high voltage transformer and the charging portion will be described. Reference numeral 24 indicates a connection terminal for applying a developing bias, and connection terminal 24a indicates the process cartridge 14.
And the connection terminal 24b is provided in the printer mechanism unit 13. Therefore, when the printer mechanism unit 13 is closed after the process cartridge 14 is attached to the apparatus main body,
The connection terminal 24a and the connection terminal 24b are configured to be automatically connected. Reference numeral 25 is a connection terminal for applying a primary charged voltage, the connection terminal 25a is provided in the process cartridge 14, and the connection terminal 25b is provided in the printer mechanism section. Therefore, like the developing bias, by closing the printer mechanism unit 13, the connection terminals 25a, 25
b is connected.

Reference numeral 26 is a switching contact portion for applying a transfer electrification voltage, 27 is a switching contact portion for applying a removal voltage of the back surface charge of the sheet P, and the switching contact portions 26, 27 are positive / positive. Copy process to get the image (first mode)
The applied voltage is switched according to the copying process (second mode) for obtaining a negative / positive image.
In addition, as in the conventional case, the high voltage transformer 23 is connected to the optical mechanism unit 12
If it is arranged, the high voltage cable becomes long, the cable may be caught when the printer mechanism 13 is closed, which not only impairs the safety but also increases the malfunction due to noise induction. It is preferable to arrange it in the vicinity of the charged portion (printer mechanism 13).

Next, a first embodiment showing the present invention will be described. FIG. 1 is a partial schematic perspective view of a high voltage switching device showing a first embodiment of the present invention, FIGS. 5A and 5B are partial side sectional views showing the operation of the high voltage switching mechanism, and FIG. 7A and 7B are schematic perspective views showing an example of a process cartridge for obtaining a negative / positive image and a process cartridge for obtaining a positive / positive image, respectively.

First, the high voltage switching mechanism will be described.
In FIGS. 1 and 5A, 33 is a linear lever, 41 is a mounting plate for the linear lever, and shafts 33a, 3 of the linear lever 33 are provided.
3b slides along the long holes 41a and 41b provided in the mounting plate 41, and the linear movement lever 33 moves linearly. A tension coil spring 35 is hooked on a hook 33e of the linear lever 33 and a hook (not shown) of the mounting plate 41,
A force in the direction of arrow A acts on the direct-acting lever 33 by the urging force of the tension coil spring 35, and the direct-acting lever 33 abuts against a stopper (not shown) of the main body of the apparatus and stands still.

Reference numeral 31 is a swing lever, and the swing lever 31 rotates about a shaft 31d as a fulcrum. A direct-acting lever 33 is engaged with the swing lever 31, and a boss 31b provided on the swing lever 31 slides in an elongated hole 33c provided on the direct-acting lever 33. The swing lever 31 and the direct-acting lever 33 are arranged in the optical mechanism section 12 as a high voltage switching mechanism section.

Next, the high voltage switching terminal portion will be described. In FIG. 6, reference numeral 26a is a switching contact, which is made of an elastic body and is electrically connected to the transfer charger by a cable. 26b and 26c are contact terminals, which are respectively connected to the high voltage transformer by a cable.
A transfer electrification voltage required to obtain a negative / positive image and a transfer electrification voltage required to obtain a positive / positive image are applied to each of c. In the figure, the switching contact 26a and the contact terminal 26c are connected, and a high voltage applied to the contact terminal 26c from the high voltage transformer 23 is applied to the transfer charger.

The high voltage switching contact portion 26 is arranged in the printer mechanism portion 13, and the printer mechanism portion 13 is connected to the optical mechanism portion 1.
When opened from 2, the power switch (not shown) is turned off, and the high voltage is not applied to the contact terminals 26b and 26c. Although the high voltage switching contact portion applied to the transfer charger 18 has been described above, the high voltage switching contact portion applied to the charge elimination needle 19 has the same configuration.

Next, the operation of this embodiment will be described.
First, as shown in FIG. 7A, the case where the process cartridge 14 provided with the protrusion 14a is mounted on the optical mechanism 12 will be described. In FIG. 1, the printer mechanism unit 13 is opened from the optical mechanism unit 12 (power switch OF
F), when the process cartridge 14 is inserted horizontally, the protrusion 14a of the process cartridge 14 moves the swing lever 31.
Since the arm 31a is pushed in, the swing lever 31 rotates in the direction of arrow C, and the direct-acting lever 33 engaged with the swing lever 31 moves in the direction of arrow B.

Next, when the printer mechanism unit 13 is pushed up and the printer mechanism unit 13 is closed, the arm 33d of the direct-acting lever 33 pushes down the switching contact 26a as shown in FIGS. 2 and 6, so that the switching contact 26a is connected. While the terminal 26c is switched to the contact terminal 26b, the arm 3 of the linear lever 33 is connected to the switching contact 27a as shown in FIG. 5 (A).
Since the force due to 3d does not act, the connection between the switching contact 27a and the contact terminal 27c does not change. When the printer mechanism unit 13 is closed, a power switch (not shown) is turned on, and a high voltage is applied from the high voltage transformer 23 to each contact terminal.
Therefore, the high voltage applied to the contact terminal 26b is applied to the transfer charger 18, and the high voltage applied to the contact terminal 27c is applied to the charge elimination needle 19.

Next, as shown in FIG. 7B, the protrusion 14a
A case where a process cartridge 14 ′ without a mark is installed in the optical mechanism section 12 will be described. When the process cartridge 14 'is inserted in FIG. 1, since the swing lever 31 is not pressed by the process cartridge 14', the linear lever 33 is in a stopped state.
Next, when the printer mechanism 13 is closed, the power switch is turned on.
As shown in FIG. 5B, the connection between the switching contact 26a and the contact terminal 26c does not change, and the connection of the switching contact is switched by the arm 33d of the direct-acting lever 33 from the contact terminal 27c to the contact terminal 27b.

Therefore, the transfer charger 18 has a contact terminal 2
The high voltage applied to 6c is applied, and the high voltage applied to the contact terminal 27b is applied to the static elimination needle 19. Reference numeral 37 shown in FIG. 2 is an insulating wall, and a high voltage applied to each contact by widening the space distance between adjacent contacts such as the switching contact 26a and the switching contact 27a or the contact terminal 26c and the contact terminal 27c. Are provided so as not to leak.

As described above, by switching the switching of the high-voltage contacts into two stages, that is, the process cartridge insertion and the printer mechanism opening / closing, the respective operations can be performed in different directions. Even if the stroke is small, there is an advantage that the creepage distance between the contacts can be sufficiently secured.

In this embodiment, the switching of the high voltage applied to the transfer charger and the discharging needle has been described, but the present invention is not limited to the above two places, and the high voltage applied to other chargers or the like. May be switched.
Further, the present invention produces the same effect in an image forming apparatus, a copying machine apparatus, a laser beam printer, etc. of a type in which the printer mechanism section 13 is fixed and the optical mechanism section 12 is rotated to open and close.

FIGS. 8 and 9 show a second embodiment of the present invention. The same parts as those of the above embodiment are designated by the same reference numerals and will be described. In this embodiment, a dustproof means is provided in order to prevent incomplete connection of the contact due to adhesion of toner, dust, dust, etc. necessary for image recording by the electrophotographic process to the contact. is there.

This embodiment will be described below. Reference numeral 51 denotes a shutter, which rotates about a shaft 52 as a fulcrum. A projection 51a of the shutter 51 is in contact with the switching contact 26a, and the elastic force of the switching contact 26a prevents the shutter 51 from descending. On the other hand, a stopper (not shown) is provided to prevent the shutter 51 from opening more than necessary to prevent the shutter 51 from rotating clockwise due to vibration or the like. Reference numeral 53 denotes a dustproof sheet, which is made of rubber or cloth, and has one end attached to the insulating wall 37 so that one end of the dustproof sheet is always in contact with the shutter 51 in the rotation range of the shutter 51.

FIG. 7 is a view for explaining the operation in which the connection of the switching contact 26a is switched by the arm 33d of the linear motion lever 33 as in the above-described embodiment. As shown in FIG. , When the shutter 51 is pushed down, the shutter 51 rotates and the projection 5 of the shutter 51
Since 1a pushes down the switching contact 26a, the switching contact 26a
The connection of a is switched from the contact terminal 26c to the contact terminal 26b. In addition to the above embodiment, the shutter and the dustproof sheet may be integrated.

FIGS. 10 and 11 show a third embodiment of the present invention. The same parts as those of the above embodiment are designated by the same reference numerals. Even if the insulating wall is provided with a low height, the creepage distance between the contacts is sufficiently secured. This embodiment will be described below.

FIG. 10 is a partial schematic perspective view of a high voltage switching device showing a third embodiment of the present invention, and FIGS. 11A and 11B are partial schematic perspective views showing the operation of the high voltage switching contact. . Figure 1
In 0 and 11 (A), 61 is a transfer charging voltage switching contact, 62 is a sheet back surface charge removing voltage switching contact, and the switching contacts 61 and 62 are the direct-acting lever 3 in the optical mechanism section 12.
It is attached to 3. Reference numeral 63 is a contact terminal for the transfer charging voltage, contact terminal 63a is connected to the transfer charger 18 by a cable, and contact terminals 63b and 63c are the high voltage transformer 2.
3 and a cable, respectively.

Reference numeral 66 is a contact terminal for removing the charge on the back surface of the seat. The contact terminal 66a is connected to the charge eliminating needle 19 by a cable, and the contact terminals 66b and 66c are connected to a high voltage transformer and a cable, respectively. FIG. 11A shows
In the diagram showing the connection when the process cartridge 14 'having no protrusion is mounted, the high voltage applied to the contact terminal 63c is applied to the transfer charger 18 and the high voltage applied to the contact terminal 66c is applied to the charge elimination needle 19.

On the other hand, FIG. 11B is a view showing the connection when the process cartridge 14 with the protrusion 14a is mounted, and the transfer charger 18 has a contact terminal 63b and the charge elimination needle 19 has a contact terminal 66b. A voltage will be applied.

As described above, in the present embodiment, since the contact terminals can be arranged in parallel, the height of the insulating walls 69 and 70 can be reduced, so that there is an advantage that a high voltage can be switched in a very small space. Further, when the printer mechanism unit 13 is opened, the switching contact and the contact terminal are similarly opened, so that even if toner, dust, dust, etc. adhere to the contact, it can be easily cleaned.

[0037]

As described above, in the image forming apparatus in which the process cartridge for obtaining the negative / positive image and the process cartridge for obtaining the positive / positive image are selectively attachable / detachable, the optical mechanism section and the printer mechanism section are provided. When the process cartridge is mounted depending on the presence or absence of protrusions or the like added to the specific process cartridge after opening, the switching mechanism provided to switch the voltage applied according to the copying process is operated, and then the optical mechanism section and the printer are operated. By adopting a two-stage switching structure in which the contacts for switching the applied voltage are connected by closing the mechanism section, the creeping distance is sufficiently secured by the operation of a small stroke of the switching mechanism, and a reliable high voltage is ensured. Switching can be realized. Therefore, it is possible to make an inexpensive and small-sized device as compared with the case of electrically switching like the conventional device. Further, since the high-voltage transformer can be arranged in the vicinity of the charging section, the expensive high-voltage cable can be shortened, the assembling workability can be improved, and the noise that affects other signal lines can be reduced. Moreover, there is no need to worry about the cable being bitten, which is advantageous in terms of safety.

[Brief description of drawings]

FIG. 1 is a partial perspective view showing a high voltage switching device according to a first embodiment of the present invention.

FIG. 2 is a schematic configuration diagram of a reader printer to which the present invention is applied in a closed state.

FIG. 3 is a schematic configuration diagram of a reader printer to which the present invention is applied in an open state.

FIG. 4 is a cross-sectional view showing the periphery of a process cartridge according to the present invention.

5A and 5B are side cross-sectional views showing the operation of the switching mechanism section according to the first embodiment.

FIG. 6 is a sectional view showing the operation of the switching contact according to the first embodiment.

FIG. 7 is an embodiment of the present invention, (A) is a perspective view of a process cartridge with protrusions, (B) is a perspective view of a process cartridge without protrusions.

FIG. 8 is a sectional view showing the operation of the switching contact according to the second embodiment.

FIG. 9 is a sectional view showing the operation of the switching contact according to the second embodiment.

FIG. 10 is a perspective view showing the operation of the switching contact according to the third embodiment.

FIG. 11 is a perspective view showing the operation of the switching contact according to the third embodiment of the present invention.

[Explanation of symbols]

4 photoconductor 12 Optical mechanism section 13 Printer mechanism 14 Process cartridge 23 High voltage transformer 26, (27) High voltage switching contact

Claims (3)

[Claims] 1. A first original for copying a positive original image into a positive image by dividing the main body of the apparatus into two parts by opening and closing, and attaching and detaching a process cartridge equipped with a developing device to and from one of the parts. In an image forming apparatus configured to select either one of a mode and a second mode for copying from a negative original image to a positive image, each process cartridge is linked with mounting of the process cartridge when the two units are opened. An image forming apparatus comprising: a switching unit that switches the mode according to the above; and a switching contact that switches by the switching unit in conjunction with the operation of closing the two machines. 2. The image forming apparatus according to claim 1, wherein there are a plurality of switching contacts, and the plurality of switching contacts are connected at the same time. 3. The image forming apparatus according to claim 1, wherein the switching contact is configured to separate when the two units are opened.