JPH1145041A - Image forming device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To surely detect the forgetting of the detection of a process unit without increasing the number of parts. SOLUTION: This device is provided with a protective shutter 31 which is located at a closing position and covers over the surface of a photoreceptor 27 when the process unit 2 is detached from a device main body 1 and when the process unit 2 is attached to the main body 1 but a protective cover 3 is opened, and located at an opening position and opens the surface of the photoreceptor 27 when the process unit 2 is attached to the main body 1 and the cover 3 is closed. The main body 1 is provided with a detection switch 17 consisting of an on/off type mechanical switch. The shutter 31 directly abuts on or separates from the switch 17 by moving to the opening and closing positions. Thus, the switch 17 is changed over.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] 1. Field of the Invention [0002] The present invention relates to an image forming apparatus such as a copying machine, a printer, a facsimile, etc., having a process unit detachable from an apparatus main body.

[0002]

2. Description of the Related Art Conventionally, an image forming apparatus has a photoconductor,
Some include a process unit in which a charging device, a developing device, and the like are integrated into a single unit that can be attached to and detached from an apparatus main body. Unless the process unit is mounted on the apparatus main body, image formation cannot be performed. Therefore, various proposals have been made for detecting the forgetting to mount the process unit.

[0003] For example, there is a type provided with a dedicated switching means such as a lever interlocked with the attachment / detachment of a process unit and a detection switch switched by the switching means. Also,
In some printers, when a printing operation is performed in a state where the process unit is not mounted on the apparatus main body, a paper jam occurs without fail, so that it is possible to detect a forgetting to mount the process unit. Further, there is also a configuration in which forgetting to mount a process unit is detected by utilizing the fact that the output value of a reflection type sensor for detecting toner empty is different between when the process unit is mounted and when the process unit is not mounted.

[0004]

However, when the dedicated switching means and the detection switch are provided, the number of parts increases, and it is necessary to secure a space for arranging them in the apparatus main body. Cause an increase.

Further, when detecting the forgetting to mount the process unit by generating the above-mentioned paper jam, it is necessary to perform a complicated paper jam handling operation every time the user forgets to mount the process unit.

Further, the method utilizing the change in the output value of the reflection type sensor for detecting the toner empty has a problem in detection accuracy.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems in the conventional image forming apparatus, and does not increase the number of parts and does not reduce the space in the apparatus main body. An object is to surely prevent forgetting to attach.

[0008]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, the present invention provides an openable / closable protective cover provided on an apparatus main body, a photoreceptor detachable inside the apparatus main body, and at least a photoconductor. A process unit provided with a body protection shutter, wherein the protection shutter is provided when the process unit is removed from the apparatus main body and when the process unit is mounted on the apparatus main body but the protection cover is opened. In an image forming apparatus, the process unit is mounted on the main body of the apparatus while the protective unit is closed, and the protective cover is closed to open the photoconductor surface while the process unit is mounted on the apparatus main body. A detection switch composed of an on / off type mechanical switch is provided in the main body, and the protective shutter directly contacts the detection switch according to its open / close position. By separating from the detection switch, it is characterized in that so as to switch the detection switch.

In the image forming apparatus of the present invention having the above-described structure, since the detection switch is switched by directly contacting or separating the protection shutter from the detection switch, the protection cover is closed, that is, the process unit. Can be reliably detected as being attached to the apparatus main body and the protective cover is closed, so that forgetting to attach the process unit can be prevented. Also,
Since there is no need to provide a dedicated switching means such as a lever that works in conjunction with the attachment / detachment of the process unit, the number of parts is reduced,
It is possible to prevent the space in the apparatus main body from being reduced.

[0010]

Next, the present invention will be described in detail based on an embodiment shown in the drawings. As shown in FIGS. 1 and 2, an apparatus main body 1 of an image forming apparatus according to an embodiment of the present invention.
, The process unit 2 is detachably accommodated. Further, the apparatus main body 1 is provided with a protective cover 3 for opening the opening 1a provided on the right side in the figure when a paper jam is processed or when the process unit 2 is attached / detached.

The lower end of the protective cover 3 is pivotally supported by a support shaft 4 provided on the apparatus main body 1. With the support shaft 4 as a fulcrum, as shown by arrows A1 and A2, the closed position shown in FIG.
It can rotate between the open positions shown by. The protective cover 3 includes a transfer roller 6 and a registration roller 7.
a, 7b and a cooling fan 8 are provided. further,
The protective cover 3 is provided with a locking mechanism (not shown) for holding the closed position shown in FIG. Furthermore, a drive pin 9 is fixedly provided near the support shaft 4 of the protective cover 3.

On the other hand, an inverted L-shaped lever 12 is swingably supported on a support shaft 11 fixed to the apparatus main body 1. The lever 12 is supported by the support shaft 11 at a position slightly centered from the lower end, and a guide groove 12a formed of a long groove is provided at the lower end. This guide groove 12
A drive pin 9 provided on the protective cover 3 is inserted into a. The rack 12c meshes with a gear 13 rotatably provided in the apparatus main body 1. Also, this gear 1
Reference numeral 3 denotes a gear 1 rotatably provided in the apparatus main body 1.
4 is engaged. Further, as shown in detail in FIG.
A rotating shaft 15 of the gear 14 has a lever 1 for opening and closing a protective shutter 31 provided in a process unit 2 described later.
6 is fixed, and the lever 16 rotates integrally with the gear 14.

A detection switch 17 for detecting whether or not the process unit 2 is mounted is provided in the apparatus main body 1. The detection switch 17 outputs an ON signal when the cantilever 17a presses the button 17b, and outputs an OFF signal when the cantilever 17a releases the pressing of the button 17b. The output signal of the detection switch 17 is input to a control device 18 provided in the apparatus main body 1 as schematically shown in FIGS. 1 and 2, and the control device 18 turns on / off the detection switch 17. The power switch 22 for communicating / cutting off the power supply from the power supply 19 to the operation panel section 21 is opened and closed in response to the command.

In addition, in the apparatus main body 1, there are provided a paper feed cassette 23, a paper feed roller 24, a fixing device 26 having a rubber roller 26a and a heat roller 26b, and the like.

As shown in FIG. 3, the process unit 2 includes the photosensitive member 27, the charging device 28, the developing device 29, and the cleaner blade 30 as one unit. The charging device 28 includes a charging brush 28a. The developing device 29 includes a developing sleeve 29.
a, a stirring blade 29b and the like.

As shown in FIG. 1, when the process unit 2 is mounted on the apparatus main body 1 and the protective cover 3 is in the closed position, the photosensitive member 2 provided on the process unit 2 is provided.
Reference numeral 7 faces the transfer roller 6 provided on the protective cover 3. The process unit 2 includes a protective shutter 31 for protecting a portion of the surface of the photoconductor 27 facing the transfer roller 6.
Is provided.

The protective shutter 31 is supported by a support shaft 32 having a base end fixed to the process unit 2 by arrows B1,
It is supported rotatably in the direction of B2. On the other hand, it is urged in the direction of arrow B1 by elastic means (not shown). As shown in FIG. 4, an arc-shaped contact portion 31 a is provided at the base end of the protective shutter 31.
The protective shutter 31 is opened and closed by engaging the lever 16 of the apparatus main body 1 with 1a.
On the other hand, a projection 31b for engaging with the cantilever 17a of the detection switch 17 is provided on the distal end side of the protection shutter 31.

As shown in FIG. 3, when the process unit 2 is detached from the apparatus main body 1, the protective shutter 31 is in a closed position for covering the surface of the photosensitive member 27 by the urging force of the elastic means.

As shown in FIG. 2, when the protective cover 3 of the apparatus main body 1 is opened, the process unit 2 is opened through the opening 1a.
Can be mounted inside the apparatus main body 1. When the process unit 2 is correctly mounted on the apparatus main body 1, the support shaft 32 of the protective shutter 31 on the process unit 2 side coincides with the rotation center of the gear 14 on the apparatus main body 1 side. The lever 15 fixed to the gear 14 is located on the photoconductor 27 side of the protective shutter 31. As shown in FIG. 2, the process unit 2 is mounted on the apparatus main body 1, but when the protective cover 3 is opened, the protective shutter 31 moves the process unit 2 shown in FIG. It is in the closed position, as in the removed state. When the protective cover 31 is at the closed position, the protrusion 31b of the protective cover 31 is separated from the cantilever 17a of the detection switch 17. Therefore, the cantilever 17a does not press the button 17b, and the detection switch 17 outputs an off signal to the control device 18. While the OFF signal is being input, the control device 1
8 turns off the power switch 22, so that power supply to the operation panel unit 21 is cut off.

Next, the protective cover 3 in the open state shown in FIG.
Is rotated toward the closed position as shown by the arrow A1, the driving pin 9 also moves along the arc A1 in the direction of the arrow A1 around the support shaft 4 of the protective cover 3. Therefore, the guide groove 12 engaged with the drive pin 9
a with the support shaft 11 as a fulcrum and an arrow C1
Rotate in the direction. The rotation of the lever 12 causes the gear 1
3 rotates counterclockwise in the figure, and the gear 14 rotates clockwise. Therefore, the lever 16 also rotates clockwise from the upward position shown in FIG. Since the lever 16 contacts the contact portion 31a of the protection shutter 31 and pushes up the protection shutter 31 against the urging force of the elastic means, the protection shutter 31 also rotates with the support shaft 32 as the lever 16 rotates clockwise. About the arrow B2 in the direction of arrow B2.

As shown in FIG. 1, when the opening 1a is completely closed by the protective cover 3, the protective shutter 31 pivots to an open position in which the tip is located on the lower side in FIG. Is opened and faces the transfer roller 6. When the protective shutter 31 is in the open position, the protrusion 31b provided on the distal end side of the protective shutter 31 presses the distal end of the cantilever 17a of the detection switch 17, and the cantilever 17a presses the button 17b. In this state, the detection switch 17 outputs an ON signal to the control device 18, and the control device 18 to which the ON signal has been input closes the power switch 22. Therefore, power is supplied from the power supply 19 to the operation panel 21, and the operator can execute printing.

On the other hand, when the protective cover 3 closing the opening 1a is rotated in the opening direction indicated by the arrow A2 as shown in FIG. 1, the lever 12 rotates in the direction of the arrow C2 in conjunction with this rotation. Accordingly, the gear 13 rotates clockwise, and the gear 1
4 rotates counterclockwise. Therefore, the lever 15 rotates counterclockwise from the lower position shown in FIG. 1 to the upper position shown in FIG. The protection shutter 31 includes a contact portion 31a.
Is rotated counterclockwise by the urging force of the elastic means in a state in which the lever comes into contact with the lever 16, and returns to the position covering the surface of the photoconductor 27 as shown in FIG. As a result, the projection 31b of the protection shutter 31 separates from the detection switch 17, and the power supply to the operation panel 21 is cut off.

If the protective cover 3 is closed without mounting the process unit 2 in the apparatus main body 1, the protective shutter 31 of the process unit 2 can be closed.
Cantilever 1 of the detection switch 17 pressed by the
7a is a state in which the button 17b is not pressed. Therefore, also in this case, the power supply from the power supply 19 to the operation panel unit 21 is cut off.

As described above, in this embodiment, the on / off state of the detection switch is switched by the protection shutter 31 directly contacting or separating from the detection switch.
Power is supplied to the operation panel unit 21 only when the protection shutter 31 is in the open position, that is, when the process unit 2 is mounted on the apparatus main body 1 and the protection cover 3 is closed. Therefore, it is possible to reliably detect that the process unit 2 is not mounted on the apparatus main body 1 and that the protective cover 3 is not closed.

In this embodiment, the protection shutter 31 directly contacts or separates without providing a special mechanism for interlocking with the mounting and dismounting of the process unit in order to detect the mounting of the process unit. Since the switch 17 is turned on / off, an increase in the number of components can be suppressed, and the space in the apparatus body 1 can be effectively used.

It should be noted that the present invention is not limited to the above embodiment, and various modifications are possible. For example, in the above embodiment, when the process unit is not mounted on the apparatus main body or when the process unit is mounted on the main body but the protective cover is in the open position, the power supply to the operation panel unit is shut off. Although a configuration is adopted, in these cases, a warning may be displayed on a liquid crystal touch panel or the like provided on the operation panel unit, or a warning lamp provided on the operation panel unit may be turned on. Further, the detection switch is not limited to the above, and may be an on / off type mechanical switch. Further, in the above embodiment, the protection shutter may be in contact with the detection switch when in the closed position, and may be separated from the detection switch when in the open position.

Further, in the above embodiment, the protective cover is opened and closed after the process unit is mounted on the apparatus main body itself. However, by closing the protective cover after mounting the process unit on the protective cover side, the process unit is closed. May be mounted in the apparatus main body, and at this time, it may be detected that the process unit has been forgotten to be mounted. Further, the protective cover is opened laterally in FIGS. 1 and 2, but may be opened upward or forward.

[0028]

As is apparent from the above description, in the image forming apparatus of the present invention, the on / off type mechanical switch is provided by the protective shutter directly contacting or separating from the detection switch according to the open / close position thereof. Since the configuration is such that the detection switch composed of is switched, it is possible to reliably detect that the process unit has been forgotten to be mounted. In addition, since the protection shutter is configured to directly switch the detection switch as described above, it is not necessary to provide a dedicated switching unit such as a lever that operates in conjunction with the mounting and dismounting of the process unit. Can be prevented from being reduced.

[Brief description of the drawings]

FIG. 1 is a partial schematic configuration diagram of an image forming apparatus showing a state where a protective cover is at a closed position.

FIG. 2 is a partial schematic configuration diagram of the image forming apparatus showing a state where a protective cover is in an open position.

FIG. 3 is a schematic configuration diagram illustrating a process unit.

FIG. 4 is an enlarged perspective view of a main part showing a relationship between a lever and a protective shutter.

[Description of sign]

 DESCRIPTION OF SYMBOLS 1 Main body 2 Process unit 3 Protective cover 17 Detection switch 27 Photoconductor 31 Protective shutter

Claims (1)

[Claims] An openable / closable protective cover provided on an apparatus main body; a process unit detachable inside the apparatus main body, provided with at least a photoconductor, and a protective shutter for the photoconductor. The protective shutter is closed when the process unit is removed from the apparatus main body and when the process unit is mounted on the apparatus main body but the protective cover is opened, and covers the photosensitive member surface, while the process unit is closed. In an image forming apparatus which is mounted on an apparatus main body and is opened when a protective cover is closed to open a photosensitive member surface, a detection switch comprising an on / off type mechanical switch in the apparatus main body. The protection shutter is contacted directly with the detection switch or separated from the detection switch in accordance with the opening / closing position, so that the detection is performed. An image forming apparatus characterized in that in the switch the switch.