JPH09127808A - Image forming device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To facilitate the attachment/detachment of a fixing means by laying an outside opening/closing cover on the back side of a device main body down, so as to open the back side of the device main body and almost horizontally pulling out the fixing means installed on the back side of the device main body therefrom, in the direction sward the downstream side of feeding a paper sheet. SOLUTION: This image forming device is constituted of a fixedly installed first main body 110 and a second main body 120 capable of almost horizontally moving with respect to the first main body 110. In the first main body 110, an exposure optical system 12, a transfer means 14, a separating means 15, a paper feeding means 22, the fixing means 23, a paper ejecting means 24, a power unit 25, etc., are arranged. A developing means 13 can be attached to/detached from the front side, in such a manner that a door in the vicinity of the center of the front side 1F of the device main body is opened. Further, in view of a process, the fixing means 23 is formed into such a shape that it is installed on the back side 1R of the device main body. Therefore, a device back door 111 is opened and the fixing means 23 can be easily attached/detached horizontally in the downstream direction of feeding the paper, from the opening part of the back of the device main body.

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 such as an electrophotographic copying machine, a printer and a facsimile, and more particularly to a heat fixing unit and a power supply unit which can be attached to and detached from a main body of the image forming apparatus.

[0002]

2. Description of the Related Art In a current image forming apparatus, an image forming body, a developing means and the like need to be replaced. Therefore, it is necessary to divide the image forming apparatus into two in order to replace the image forming body and the developing means. Conventionally, since the image forming apparatus is divided into two,
There was a clamshell system in which one side is a fulcrum and one opposite side is open. FIG. 5 is a sectional view showing an open state of the clamshell type color image forming apparatus. The image forming apparatus includes a corona charger 11, an image exposure unit 12, and a plurality of developing devices 13Y, 1 in the circumferential direction of a rotating image forming body 10.
An image forming unit including a developing unit 13 including 3M, 13C, and 13K, a belt transfer unit 14, a separating unit 15, and a cleaning unit 16 are provided, and while the image forming body 10 is rotated a plurality of times, By repeating charging, image exposure and development on the peripheral surface of the image forming body 10, different color toner images are superimposed to form a color toner image. Reference numeral 17 includes a plurality of toner supply containers 17A, and the plurality of developing units 13Y, 13
It is a toner replenishing means for controlling and replenishing toner to M, 13C and 13K, respectively. On the other hand, the recording material (transfer paper or the like) P stored in the paper feeding cassette 21 is sent out by the paper feeding means 22 and the color toner image is transferred to the recording material P by the belt transfer means 14, and the separating means 15 is provided. After being separated from the image forming body 10 by the fixing means 23, it is heated and fixed by the fixing means 23 and discharged to the outside of the apparatus main body by the paper discharging means 24. The image forming apparatus main body 1 is divided into an upper main body 1A and a lower main body 1B and has a clamshell structure that can be opened and closed with a support shaft 2 orthogonal to a conveyance path 3 of the recording material P as a fulcrum. The above-described image forming process is performed by the upper main body 1A and the lower main body 1
It is performed with B and B closed. FIG. 5 is a sectional view of the image forming apparatus showing a state in which the upper body 1A is rotated about the support shaft 2 by about 30 ° and opened.

[0003]

In the above clamshell type image forming apparatus, as shown in FIG. 5, the front surface (left side in the drawing) of the apparatus main body is opened, and the processing of the paper jam generated in the inside of the apparatus main body and the consumable consumption are performed. The replacement can be easily performed from the front side of the device body. However, in the clamshell system, the image forming body 10 is exposed to the outside when the front surface of the apparatus main body is opened, so that the hand or the like touches the image forming body 10 during the consumable exchange, and the image forming body 10 is exposed. May damage your. Therefore, in this method, the image forming body 10 is exposed to the outside unless the image forming body 10 is provided with a special movable shielding means.

In order to solve this problem, a method has been considered in which the image forming apparatus is horizontally divided, the upper surface of the apparatus main body is opened, and the image forming body or the like is exchanged through the opening. In the image forming apparatus adopting this method, considering the arrangement of the process means in the main body of the image forming apparatus,
The developing means is attached to and detached from the image forming apparatus more often than other process means. Further, toner replenishment is frequently performed, and from the viewpoint of operability, the toner replenishing means is preferably arranged on the front side of the apparatus, and accordingly, the developing means to which the toner is supplied is also preferably arranged close to the toner replenishing means. Therefore, it is preferable that the developing means is arranged on the front side of the apparatus main body.
On the other hand, when the developing means is installed on the front side of the apparatus, there is a problem in which part the fixing means should be attached and detached.

In an image forming apparatus which employs a system in which the upper surface of the apparatus is divided horizontally and the image forming body or the like is exchanged through the opening, the developing means is disposed on the front side of the apparatus as described above, From the front of the apparatus main body, the image forming body,
It is easier to attach and detach the transfer unit from the upper surface of the apparatus. When the developing means is installed on the front side of the apparatus main body in this manner, the fixing means is installed close to the rear side of the apparatus main body. When attaching and detaching the fixing means, the image forming body or the like interferes when trying to attach and detach from the front side of the main body of the apparatus, and if the configuration is such that it is easy to attach and detach from the front side, the inside of the main body of the apparatus becomes rather complicated, which is not preferable. Further, the fixing unit has a long life as compared with other process units, and replacement work is not so frequent.

[0006]

An image forming body for solving the above problems, developing means for forming a toner image on the image forming body, and a toner image formed on the image forming body are transferred to a recording material. In an image forming apparatus having a transfer means and a fixing means for fixing the transferred toner image to a recording material, and the developing means is installed on the upstream side of the feeding in the apparatus main body, at least the developing means is an apparatus. It is characterized in that it is detachable from the upstream side of the main body in the recording material feeding direction, and the fixing means is detachable by being pulled out substantially horizontally to the downstream side of the main body of the apparatus in the recording material feeding direction.

The present invention relates to a fixing means, a method for attaching and detaching a power supply unit, and an arrangement of the fixing means and the power supply unit.

In the image forming apparatus of the present invention, the fixing means installed on the rear side of the main body of the apparatus is opened to open the rear cover of the main body of the apparatus to open the rear surface of the main body of the apparatus, and from there, the fixing means is made substantially horizontal in the downstream direction of paper feeding. Withdraw. With such a structure, the fixing unit can be easily attached and detached.

A power supply unit in which a DC power supply and an AC power supply are integrated may break down, so it is necessary to install it so that it can be easily replaced. Further, since it is necessary to change the power supply voltage depending on the destination, it is better to have a structure in which the power supply unit of each voltage can be easily attached in the production process. Therefore, the power supply unit is installed on the rear side of the main body of the apparatus like the fixing means, and the exterior of the rear surface of the main body of the apparatus is tilted down to open the rear surface of the main body of the apparatus so that it can be attached and detached substantially horizontally. Further, the fixing means and the power supply unit are installed in parallel vertically, and the upper surface of the power supply unit is used as a guide when the fixing means is attached to and detached from the apparatus main body. By doing so, the connection between the fixing unit and the power supply unit is facilitated, and the fixing unit is easily attached to and detached from the apparatus main body. By doing so, the above object is achieved.

[0010]

FIG. 1 is an overall configuration diagram of a color image forming apparatus (color printer) as an embodiment of the image forming apparatus according to the present invention.

(Charging / Electrification) In FIG. 1, reference numeral 10 designates a photosensitive drum which is an image bearing member, which is formed by coating an OPC photosensitive layer on the drum and is grounded and rotated clockwise. 11
In scorotron charger, provided by a corona discharge by a grid and the corona discharge wire which uniform charging has been potential held in the V _G of the V _H the photosensitive drum 10 peripheral surface. Prior to the charging by the scorotron charger 11, exposure is performed by the pre-charging exposure means (PCL) 11A using a light emitting diode or the like to eliminate the history of the photoreceptor until the previous printing, and the peripheral surface of the photoreceptor is neutralized. deep.

(Exposure) After the photosensitive drum is uniformly charged, the image exposure means 12 performs image exposure based on an image signal. The image exposure means 12 passes through a polygon mirror 121, a collimator lens 122, an fθ lens 123, etc., which rotate using a laser diode (not shown) as a light emitting source, the optical path is bent by a reflection mirror 124, and scanning is performed. A latent image is formed by 10 rotations (sub-scanning). In this embodiment, the character portion is exposed,
An inverted latent image is formed such that the character portion has a lower potential _VL .

(Development) Yellow (Y), magenta (M), cyan (C), black (K) are formed around the periphery of the photosensitive drum 10.
There is provided a developing means 13 composed of developing devices 13Y, 13M, 13C and 13K respectively containing a developer composed of toner and a carrier such as a toner. This is performed by the rotating developing sleeve 131. The developer consists of a carrier in which ferrite is used as a core and is coated with an insulating resin around it, and a toner whose main component is polyester and pigments according to the color and charge control agents, silica, titanium oxide, etc. are added. The agent is regulated by the layer forming rod 132 on the developing sleeve 131 to have a layer thickness of 300 to 600 μm, and is conveyed to the developing area.

[0014] 0.4~1.0mm gap is greater than the layer thickness (developer) to the developing sleeve 131 in the developing zone between the photosensitive drum 10, the DC bias of the AC bias and V _DC of V _AC during which The signals are superimposed and applied. V _DC and V _H, for charging the toner are the same polarity, the toner given the opportunity to leave from the carrier by V _AC and V
_It does not adhere to the _VH portion having a higher potential than _DC, but adheres to the _VL portion having a lower potential than _VDC , and visualization (reversal development) is performed.

After the visualization of the first color is completed, the process for forming the image of the second color is started, the uniform charging is performed again by the scorotron charger 11, and the latent image based on the image data of the second color is formed by the image exposing means 12. It is formed. At this time, the charge elimination by the PCL 11 performed in the image forming process of the first color is not performed because the toner attached to the image portion of the first color scatters due to the sudden decrease in the potential around the image.

A latent image similar to that of the first color is formed on the portion of the photosensitive member having the potential of V _H all over the peripheral surface of the photosensitive drum 10 without the image of the first color, and development is performed. However, in the portion where the first-color image is developed again, the latent image of V _M ′ is formed by the light-shielding toner of the first color and the electric charge of the toner itself.
Developing in response to the potential difference between the _DC and V _M 'is performed. In the overlapping portion of the first color image and the second color image, development of the first color is performed by V
_When the latent image of _L is formed, the balance between the first color and the second color is lost, so that the exposure amount of the first color is reduced and V _H > V _M >
In some cases, the intermediate potential may be V _L.

An image forming process similar to that for the second color is performed for the third color and the fourth color, and the fourth color is formed on the peripheral surface of the photosensitive drum 10.
A visible color image is formed.

(Toner Replenishment) The toner replenishing means 17 is provided with a plurality of toner containers 17A, accommodates the toner discharged from the toner container 17A, and supplies it through a replenishing path (not shown).
The toner corresponding to each of the plurality of developing units 13Y, 13M, 13C and 13K is controlled and replenished.

(Paper feeding) On the other hand, the recording material P stored in the paper feeding cassette 21 is sent out by the half-moon roller 221 of the paper feeding means 22 and temporarily stopped by the registration roller 223 via the intermediate roller 222, When the transfer timing is adjusted, the registration roller 223 is rotated to feed the sheet to the transfer area.

(Transfer, Fix, Discharge) In the transfer area, the transfer roller 14 is pressed against the peripheral surface of the photosensitive drum 10 in synchronism with the transfer timing to sandwich the recording material P fed. The color image is transferred at once.

Then, the recording material P is discharged at almost the same time by the separating brush 15 which is brought into pressure contact with the photosensitive drum 10.
After being separated by the peripheral surface of the sheet, the sheet is conveyed to the fixing unit 23, and the toner is welded by heating and pressurizing the heat roller 231 and the pressure roller 232, and then discharged to the outside of the apparatus via the sheet discharge roller 24. It should be noted that the transfer roller 14 and the separation brush 15 are withdrawn from the peripheral surface of the photosensitive drum 10 after the recording material P has passed to prepare for the next toner image formation.

(Cleaning) On the other hand, the photosensitive drum 10 from which the recording material P has been separated removes and cleans the residual toner by the pressure contact of the blade 161 of the cleaning device 16, and again receives the charge removal by the PCL 11A and the charge by the charger 11. The next image forming process is started. It should be noted that the blade 161 moves immediately after the cleaning of the surface of the photoconductor is completed and retracts from the peripheral surface of the photoconductor drum 10.

The image forming apparatus according to the present invention comprises a first main body 110 fixedly installed and a second main body 120 movable substantially horizontally with respect to the first main body. In the first main body 110, the exposure optical system 12, the transfer unit 14, the separating unit 15, the sheet feeding unit 22, the fixing unit 23, the sheet discharging unit 24.
A power supply unit 25 and the like are provided. Second body 1
An image forming body 10, a corona charger 11, a pre-charging exposure unit 11A, an image exposure unit 12, a developing unit 13, a cleaning unit 16, a toner replenishing unit 17, and the like are provided at 20.

The above-described image forming process is performed in a state where the second main body 120 is housed in the first main body 110 of the image forming apparatus as shown in FIG. FIG. 2 shows the movable second main body 120 when the image forming apparatus is not in operation.
FIG. 3 is a cross-sectional view showing a state in which the image forming apparatus 1 is horizontally moved with respect to 0 and is positioned on the right side in the drawing to open the inside of the image forming apparatus 1. In this open state, the recording material P inside the first main body 110 is
The transfer path 3, the transfer unit 14, the separating unit 15, the inlet of the fixing unit 23, and the outlet of the paper feeding unit 22 are exposed to the upper surface of the apparatus. Further, the corona charger 11 disposed inside the second main body 120 (on the left side in the drawing) and the pre-charging exposure means 1
1A, cleaning means 16 and the like are also exposed. In this open state, the jammed paper on the transport path 3 can be easily removed, and the above-mentioned members can be easily repaired and inspected. In this configuration, as shown in FIG. 2, even when the second main body 120 is pulled out, the image forming body 10 is surrounded by the manual feed tray, the cleaning unit 16, and the developing unit 13, so that the jam treatment is performed from the upper surface of the apparatus main body 1. Image forming body 10
Never touch. The second main body rides on a guide rail (not shown), can be pulled out and moved on the rail, and the stopper limits the stop position.

1 and 2, in the image forming apparatus according to the present invention, the upstream side of the feeding of the recording material P on the right side of the drawing is the front side 1F of the apparatus main body, and the discharging side of the recording material P on the left side of the drawing is the apparatus main body. It is the rear side 1R.

The developing means 13 can be attached and detached from the front side by opening the door 130 near the center of the front side 1F of the apparatus main body in the state shown in FIG. Toner container 17A of toner replenishing means 17
Can be detached from the front side by opening the door 121 on the upper side of the front side of the apparatus main body 1F. Further, a paper feed cassette 21 is attachable / detachable below the front side 1F of the apparatus main body. A manual paper feed tray 210 can be erected above the insertion port of the feeding cassette 21.

By the way, the image forming body 10 and the developing means 13 are
Compared with other process means, the number of times of attachment and detachment is large, and its service life is short. Further, since the toner is consumed, it is necessary to frequently replace the toner replenishing container 17A with respect to the toner replenishing means 17 to replenish the toner. Therefore, in consideration of operability, as shown in FIG. 1, the developing means 13 is arranged on the front side 1F of the apparatus main body so that it can be attached and detached from the front side 1F of the apparatus main body. Further, in order to facilitate toner replenishment, the toner replenishing container 17A is installed above the front side 1F of the apparatus main body. Further, as shown in FIG.
The separating means 15, the paper feeding means 22 and the like can be attached and detached from the front side 1F of the apparatus main body through the upper surface of the apparatus main body.

As shown in FIG. 2, the second main body 120 is slid so as to be in an open state, and further, the image forming body 10, the corona charger 11, the pre-charging exposure means 11A and the cleaning means 16 are integrally formed as a unit stand. After moving 100 along the support rail to the vicinity of the center on the left side in the drawing, the unit mount 100 can be detached from the support rail, grasped, and taken out upward from the opening in the upper part of the apparatus main body.

The transfer means 14 and the separating means 15 can also be taken out upward from this opening.

Since the process means are arranged as described above, the fixing means 23 is provided on the rear side 1R of the apparatus main body from the process stage.
It will be installed in. As shown in FIGS. 3 and 4, the apparatus rear door 111 is opened so that the apparatus can be horizontally attached / detached from the opening on the rear surface of the apparatus main body in the downstream direction of sheet feeding. FIG. 3 is a cross-sectional view of the vicinity of the rear surface of the main body of the image forming apparatus, showing a process of opening the rear door 111 of the apparatus and taking out the fixing unit 23. FIG.
FIG. 4 is a perspective view of the vicinity of the rear surface of the apparatus main body.

The fixing means 23 includes the power supply unit 2
5 is placed on the upper surface portion 25A of
A fixing plate (not shown) installed inside 2 is positioned and fixed by a positioning boss and a screw. The power supply unit 25 is fixed to the frame 113 of the apparatus body. The power supply unit 25 includes an AC power supply for heating the heat source of the heat roller 231 of the fixing unit 23, the scorotron charger 11, the developing unit 13, the transfer unit 14, the separating unit 15,
The drive means and the DC power source for driving the control means are integrally configured. Reference numeral 114 denotes a connector that electrically connects the fixing unit 23 and the power supply unit 25. One receptacle of the connector 114 is fixed to the power supply unit 25, and the other plug is fixed to the fixing unit 23. When 23 is fixed, the connectors are connected and conductive.

The apparatus rear door 111 is locked at the time of image formation, and is closed and locked at the apparatus main body rear side.

Opening 112 on the rear side of the main body of the apparatus on the downstream side of sheet feeding
The device rear door 111 is pivotally supported by a support shaft 115, and is rotated about the support shaft 115 in the direction of arrow E so that the opening 112 can be opened and closed. The fixing unit 23 and the power supply unit 25 can be attached and detached in the state shown in the drawing in which the apparatus rear door 111 is opened.

First, when taking out the fixing means 23,
The positioning boss and the screw are removed from the fixing plate, the fixing means 23 is gripped, and the upper surface 25A of the power supply unit 25 is slid and pulled out. At this time, the fixing means 23
Both side surfaces are loosely regulated by the left side panel 116 and the right side panel 117 of the apparatus body and can be pulled out in the downstream direction of the sheet feeding. By pulling out the fixing unit 23, the connector 114 is separated and the electrical connection is cut off.

The upper surface 25A of the power supply unit 25 is
It serves as a guide for attaching and detaching the fixing means 23. The upper surface portion 25A of the power supply unit 25 has a groove portion, and the lower surface of the fixing means 23 has a protrusion that fits the groove portion, and the fixing means 23 is horizontally drawn out along the groove portion. Since the fixing means 23 has a certain weight, there is no operability if there is no guide up to the installation position of the fixing means 23.
Therefore, the upper surface portion 25A of the power supply unit 25 is fixed to the fixing unit 23.
If the guide is used, the operability can be improved, and it is advantageous in terms of cost because no special guide means is required.

The position A in FIG. 3 shows the fixing position of the fixing means 23, and the position B shows the state in which the fixing means 23 is slid and pulled out halfway. At the position B, the fixing means 23 is gripped, lifted, and taken out to the outside. The C position indicates the position of this extracted state. The fixing means 23 may be provided with a handle for easy gripping.

By adopting such a structure, the fixing means 23 can be easily attached and detached. With such a configuration, the user has to turn to the rear of the main body of the apparatus in order to attach / detach the fixing means 23, but the fixing means 23 has a long service life, and in consideration of easiness of attachment / detachment, such a structure is provided. good. This structure is also excellent for making the apparatus main body smaller and simpler.

A power source for driving and controlling each part of the image forming apparatus comprises a power source unit 25 by integrating a DC power source and an AC power source, and as shown in FIG. 3 and FIG. 23 is installed on the back side of the apparatus 23, and similarly to the fixing unit 23, from the apparatus body back side 1R to the frame 113 of the apparatus body.
It is arranged so that it can be horizontally attached and detached in the downstream direction of the paper feeding while sliding it up (in the direction of the broken line arrow D shown in FIG. 3). By the movement of the fixing means 23, the connector 114 is automatically connected or disconnected. Therefore, it is not necessary to operate a bundle cord, a plug, a connector, or the like. By installing the power supply unit 25 below the fixing means 23, connection with the fixing means 23 is easy. Further, since it can be horizontally attached and detached from the rear side 1R of the apparatus main body, there is an advantage that various power supply units can be easily attached depending on the destination.

[0039]

According to the image forming apparatus of the present invention, the fixing means installed on the rear side of the apparatus main body is opened in the opening / closing outer cover of the rear side of the apparatus main body to open the rear side of the main body of the apparatus, and from there, in the downstream direction of paper feeding. Pull it out horizontally. With such a structure, the fixing unit can be easily attached and detached. In addition, since the power supply unit that integrates the DC power supply and AC power supply may break down, it was installed on the rear door side of the device for easy replacement. In addition, because it is necessary to change the power supply voltage depending on the destination, we have arranged the power supply unit for each voltage in the production process so that it is easy to install. Therefore, the power supply unit is installed on the rear side of the main body of the apparatus like the fixing means, and the exterior of the rear surface of the main body of the apparatus is tilted down to open the rear surface of the main body of the apparatus so that it can be attached and detached substantially horizontally. Further, the fixing means and the power supply unit are installed in parallel vertically, and the upper surface of the power supply unit serves as a guide when the fixing means is attached to and detached from the main body of the apparatus, so that the fixing means and the power supply unit can be easily connected to each other. The means can be easily attached to and detached from the device body. Further, since the fixing device is adjacent to the upper part of the power supply unit, the wiring from the power supply unit to the fixing device can be reduced.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view of an image forming apparatus showing a state in which an upper body is rotated and opened.

FIG. 2 is a cross-sectional view showing a state in which the inside of the image forming apparatus is opened by sliding the second main body with respect to the first main body.

FIG. 3 is a cross-sectional view of the vicinity of the rear surface of the main body of the image forming apparatus, showing the process of opening the rear door of the apparatus and taking out the fixing unit.

FIG. 4 is a perspective view near the rear surface of the apparatus main body.

FIG. 5 is a cross-sectional view showing an open state of a clamshell type color image forming apparatus.

[Explanation of symbols]

 1 Image Forming Device Main Body (Device Main Body) 1F Device Main Body Front Side 1R Device Main Body Back Side 3 Recording Material Conveying Path 10 Image Forming Body 13 Developing Means 14 Transfer Means 15 Separing Means 16 Cleaning Means 17 Toner Replenishing Means 22 Paper Feeding Means 23 Fixing Means 24 Paper ejection means 25 Power supply unit 25A Upper surface 110 First body 111 Device rear door 112 Opening 113 Frame 114 Connector 115 Spindle 116 Left side panel 117 Right side panel 120 Second body

Claims (3)

[Claims] 1. An image forming body, a developing means for forming a toner image on the image forming body, a transfer means for transferring the toner image formed on the image forming body onto a recording material, and the transferred toner image. An image forming apparatus in which the developing means is installed on the upstream side of the feeding inside the apparatus body, at least the developing means is on the upstream side of the apparatus body in the recording material feeding direction. An image forming apparatus, wherein the fixing means is detachable from the apparatus body, and the fixing unit is detachable by being pulled out substantially horizontally to the downstream side of the apparatus body in the recording material feeding direction. 2. An image forming body, developing means for forming a toner image on the image forming body, transfer means for transferring the toner image formed on the image forming body onto a recording material, and the toner image on a recording paper. And the like, and a power supply unit,
In an image forming apparatus in which the developing unit is arranged on the upstream side of the power supply unit in the apparatus main body in the recording material feeding direction, at least the developing unit is detachable from the upstream side of the apparatus main body in the recording material feeding direction. In the image forming apparatus, the power supply unit can be pulled out substantially horizontally to the downstream side of the apparatus main body in the recording material feeding direction and can be attached and detached. 3. The fixing unit is installed adjacent to the upper surface of the power supply unit, and a fixing unit attachment / detachment guide for guiding at least attachment / detachment of the fixing unit is provided on the upper surface of the power supply unit, and the fixing unit is provided in the apparatus. The image forming apparatus according to claim 2, wherein the main body is pulled out substantially horizontally to the downstream side in the feeding direction and is detachable.