JPH07302007A - Image forming device - Google Patents

Abstract

PURPOSE:To miniaturize a device main body by eliminating a free part for attaching/detaching a process cartridge to/from the device main body. CONSTITUTION:The process cartridge 40 having a photoreceptor drum 41 is horizontally slid along a guide 1b to be attached/detached via an opening part, 1d on the side of the main body 1. When an opening/closing member 1e is opened, a pushing up member 91 is moved to the right and a transfer means 60 descends to a retreat position along a slope 91a, to form a gap G between a transfer roller 61 and the photoreceptor drum 41. When the opening/closing member 1e is closed, the pushing up member 91 is moved to the left to push up/arrange the transfer means 60 in an actuating position and abut the transfer roller 61 on the photoreceptor drum 41. The gap G is formed linked with the opening operation of the opening/closing member 1e so that the free part for attaching/detaching the cartridge 40 is dispensed.

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 forming an image on a recording medium.

[0002]

2. Description of the Related Art In electrophotographic image forming apparatuses such as copiers and laser beam printers used in offices, etc., especially desktop type small ones, further miniaturization is required. In these small-sized image forming apparatuses, it is general to use a process cartridge that is easy to maintain.

A process cartridge is constructed by incorporating an image bearing member in a cartridge container, and further integrally incorporating a charging device, a developing device, a cleaner and the like. The process cartridge is attached to the apparatus main body as follows, for example.

A cartridge mounting portion is provided on the opening / closing member which can be opened / closed with respect to the apparatus main body, and after mounting the cartridge on the mounting portion, the opening / closing member is closed. As a result, the cartridge is arranged at the predetermined position in the apparatus main body.

In another mounting method, a mounting portion is provided on the apparatus main body side, the opening / closing member is opened, the apparatus main body is largely opened, and the cartridge is placed along the conveyance path of the recording medium through the opening. It is attached to the mounting portion and then the opening / closing member is closed.

[0006]

However, according to the above-mentioned image forming apparatus, first, the recording mediums before and after the image formation are held substantially horizontally by the paper feed cassette and the paper discharge tray, respectively. Is common,
Therefore, it becomes impossible to make the area occupied by the apparatus body of the image forming apparatus smaller than the area of the largest recording medium used, and there is a problem that it is difficult to further reduce the apparatus body. .

Regarding the mounting of the process cartridge to the main body of the apparatus, in the case where the mounting portion is provided on the opening / closing member, the cartridge is pressed and fixed so that the cartridge does not rattle when the opening / closing member is closed. There is a need to. However, in this configuration, there is a problem that the space occupied by the member for pressing the cartridge arranged at the predetermined position of the apparatus main body tends to be large. Further, when the opening / closing member is closed, the drum gear attached to the image carrier and the drive gear on the apparatus main body side that transmits the drive force to the drum gear mesh with each other. Should also face down. When the pressure angle direction of the gear is set downward, if the opening / closing member is opened and the cartridge is taken out as it is, the two gears cannot be disengaged while meshing with each other. There is also a problem in that the number of parts is increased, such as the need to provide

On the other hand, in the case where the cartridge mounting portion is provided on the apparatus main body side, it is necessary to provide an operation space having a margin above the recording medium conveyance path in order to facilitate the attachment / detachment of the cartridge to / from the apparatus main body. is there. There is also a problem that this margin and a part of the operation space become a dead space in the structure in the apparatus main body after the cartridge is mounted, which hinders further downsizing of the image forming apparatus.

Therefore, an object of the present invention is to provide an image forming apparatus in which the process cartridge can be easily attached and detached without increasing the number of parts and the area occupied by the apparatus main body can be reduced. .

[0010]

SUMMARY OF THE INVENTION In order to solve the above problems, the structure of the present invention is an image forming apparatus for forming an image on a recording medium, in which a recording medium for feeding is supported in a vertical direction. 1 support means, second support means for supporting a recording medium after image formation in a vertical direction, and an image carrier provided above a conveying path from the first support means to the second support means Process cartridge, and the first
Information light emitting means for providing information light according to image information to the image carrier, which is provided between the supporting means and the second supporting means and above the process cartridge,
A transfer unit provided below the transport path for transferring the toner image formed on the image carrier to a recording medium;
A fixing unit for fixing the toner image transferred onto the recording medium onto the recording medium; a cartridge supporting unit on the apparatus main body side for supporting the process cartridge so as to be movable in the left-right direction in the conveying direction of the recording medium; Transfer means
It is characterized by comprising a contact / separation mechanism for movably supporting the transfer means in an operating position in which the transfer means comes into contact with the image carrier and a retracted position in which the transfer means moves away from the image carrier.

In this case, the apparatus main body has an opening for attaching / detaching the process cartridge on the side of the apparatus main body and an opening / closing member for opening / closing the opening, and the contact / separation mechanism includes the opening / closing member. The transfer means may be arranged in the operating position in correspondence with the closed state, and the transfer means may be arranged in the retracted position in correspondence with the open state of the opening / closing member.

Further, the transfer means has a bearing member that rotatably supports the transfer roller and is movably supported by the apparatus main body, and the contacting / separating mechanism is disposed below the bearing member. A push-up member that moves laterally in conjunction with the opening / closing operation of the open / close member, and an inclined surface is formed on one of the lower surface of the bearing member and the upper surface of the push-up member, and the inclined surface is formed on the other side. It is also possible to provide an engaging portion that engages and disengages, and convert the lateral movement of the push-up member into an elevating operation of the push-up member by sliding friction between the inclined surface and the engagement portion.

A feeding position for feeding the recording medium supported by the first supporting means and a transfer position by the transfer means, which are arranged in order from the upstream side to the downstream side of the transport path;
The fixing position by the fixing unit may be sequentially arranged at a lower position in this order.

Further, the information light emitting means may emit a laser beam. In this case, the information light emitting means has a semiconductor laser, a polygon mirror, a lens, and a reflection mirror, and the polygon mirror is on the first support means side and the reflection mirror is on the second support means side. It is preferable that the polygon mirror is arranged on the lower side, and the polygon mirror is arranged on the lower side and the reflecting mirror is arranged on the upper side.

The information light emitting means may have an LED array arranged to face the image carrier.

Next, the image carrier is integrated into an image forming apparatus main body by integrally forming an electrophotographic photosensitive member as the image carrier and at least one of a charging means, a developing means and a cleaning means into a cartridge. In contrast, the image carrier is provided in a detachable process cartridge, or the image carrier integrally includes an electrophotographic photosensitive member as the image carrier and a charging unit, a developing unit, or a cleaning unit. Provided in a process cartridge which is made detachable with respect to the main body of the image forming apparatus, or the image carrier is a cartridge in which at least a developing unit and an electrophotographic photosensitive member as the image carrier are integrally formed. It may be provided in a process cartridge that is detachable from the main body of the image forming apparatus.

[0017]

According to the above construction, the recording medium before the image formation and the recording medium after the image formation are supported in the vertical direction by the first supporting means and the second supporting means, respectively, so that the conveying path is shortened. It is possible to reduce the area occupied by the main body.

In addition, the process cartridge is supported by the main body of the apparatus so as to be movable in the left-right direction, and when the process cartridge is attached or detached, the transfer means is retracted from the image carrier in the process cartridge so that the process cartridge can be moved in the left-right direction. It can be easily attached and detached in any direction, and there is no need to provide a margin for attachment and detachment.

[0019]

Embodiments of the present invention will be described below with reference to the drawings. <Embodiment 1> FIG. 1 shows a schematic configuration of a laser beam printer M using a process cartridge as an example of an image forming apparatus according to the present invention. In each of the figures including this figure, the left side is the "front" of the printer body 1 and the right side is the "rear". According to this, regarding the upstream and the downstream of the recording medium P in the transport direction, the rear part is the upstream side and the front part is the downstream side. The recording medium P on which an image is to be formed is not only ordinary plain paper (copy paper), but also special paper such as thick paper and envelopes, and other than paper such as O.
Sheet material such as HP film can be used,
In this embodiment, the case of using ordinary plain paper will be described.

First, an outline of the configuration of a laser beam printer (hereinafter simply referred to as "printer") M shown in the figure will be described.

The printer M is referred to as a printer body 1 (hereinafter simply referred to as "body 1". In the following description,
The term "main body" refers to not only the frame forming the exterior of the printer M but also the frame forming the inside. ) A first supporting means 10 for supporting the recording medium P before image formation in the vertical direction is provided at the rear part, and a second supporting means 10 for supporting the recording medium P after image formation in the vertical direction is provided at the front part of the main body 1. Support means 20 is provided. Then, the lower end portion 10 a of the first supporting means 10 and the lower end portion 2 of the second supporting means 20.
0a and the conveyance path 3 extending from the rear part of the main body 1 to the front part
Connected with 0, and as a whole, a U-shaped path (hereinafter, “vertical U
Character path ". ) Is composed. The printer M also includes a process cartridge 40 in which a drum-shaped electrophotographic photosensitive member (hereinafter, referred to as “photosensitive drum”) 41 arranged immediately above the transport path 30 is integrally incorporated, and the process cartridge 40. The information light emitting means 50 arranged above, the transfer means 60 arranged below the intermediate portion of the conveying path 30 so as to face the photosensitive drum 41, and the second means on the downstream side of the conveying path 30.
Fixing means 70 arranged just below the lower end of the supporting means 20
It has and. Based on the above-mentioned vertical U-shaped path, the process cartridge 40 and the information light emitting means 50 are arranged inside thereof, the transfer means 60 is arranged outside thereof, and the fixing means 70 is arranged so as to straddle the conveyance path 30 on the downstream side. Will be arranged respectively.

The operation of the printer M having the above structure will be briefly described. First, a toner image is formed on the photosensitive drum 41 by the information light emitting means 50 and the like. On the other hand, the recording medium P is fed downward from the first supporting means 10 to convey the recording path 30.
Is supplied to the photosensitive drum 41 via the upstream side of the above, and the above-mentioned toner image on the photosensitive drum 41 is transferred to the supplied recording medium P by the transfer means 60. The recording medium P to which the toner image is transferred is fixed to the surface of the recording medium P by the fixing unit 70, then discharged upward, and supported by the second supporting unit 20 in the vertical direction.

The structure of each member will be described below in order from the first supporting means 10.

The first supporting means 10 is provided at the rear portion of the main body 1 and has an abutting portion 11, a leading end supporting portion 12, and a paper feed tray 13 in this order from below. The abutting portion 11 supports the front end of the recording medium P before image formation from below and supports the weight of the recording medium P. The tip support portion 12 is swingably supported in the front-rear direction by the main body 1 around the shaft 12a, and is urged forward by a spring 12b arranged on the back surface of the lower end portion. The front end support portion 12 biased forward is retracted rearward by a cam member (not shown) before feeding, and the above-mentioned cam member rotates to attach the recording medium P forward only during paper feeding. Energize. The highest recording medium P among the recording media P before feeding is fed by the abutting portion 11 and the separating claws to the feeding position A.
It is positioned at 1 and waits for feeding. When the recording medium P is fed, the next recording medium P is arranged at the feeding position A1 by the tip support portion 12 biased by the spring 12b. The paper feed tray 13 is arranged so as to vertically project from the rear end of the upper surface of the main body 1. The paper feed tray 13 supports the middle portion and the rear end portion of the recording medium P from the back side (rear surface side) of the recording medium P, and supports the entire recording medium P before image formation in a vertical plane. On the front side of the paper feed tray 13, two movable regulating plates 13L and 13R that regulate the position of the recording medium P in the left-right direction (refers to the left and right when viewed from the front side to the rear side), and the manual feed. A manual feed guide 13a for guiding the recording medium P at the time is arranged. In addition, at the upper end of the paper feed tray 13, extending upward,
An extension guide 13b that stably supports the recording medium P having a long length in the transport direction is arranged so that it can move in and out. The paper feed tray 13 is detachably attached to the upper surface of the main body 1. Here, the first supporting angle θ ₁ of the recording medium P before image formation, that is, the abutting portion 11 and the leading end supporting portion 1 described above.
2. The first support angle θ ₁ which is the angle formed by the recording medium P in the state of being supported in a plane by the first supporting means 10 configured by the feeding tray 13 and the like is 60 ° to 90.
By setting the angle to 0, it is possible to contribute to the reduction of the occupied area of the main body 1, and it is also possible to realize good feeding of the recording medium P that effectively utilizes gravity. The first support angle θ ₁ is preferably set to 70 ° to 75 °.

The second supporting means 20 has the above-mentioned first supporting means 10 provided at the rear portion of the main body 1, whereas the second supporting means 20 has the main body 1.
It is provided in the front part of the. The second supporting means 20 is the main body 1
Is provided on the exterior cover 2 that forms a part of the paper, and the abutting portion 21, the paper discharge tray 22, and the extension tray 2 are arranged in this order from the bottom.
Have three. The abutting portion 2 against the recording medium P after the image formation
1 supports the rear end from below, the discharge tray 22 supports the latter half of the rear side, and the extension tray 23 supports the front half from the rear side. The extension tray 23 is the discharge tray 2
2 is supported so as to be able to move up and down, and is extended above the main body 1 to extend tray 23 and paper discharge tray 22.
By means of, the recording medium P after the image formation is supported in a vertical plane. The recording medium P supported in the vertical direction
Assuming that the angle with respect to the horizontal plane is the second support angle θ ₂ , the second support angle θ ₂ is set to 55 ° to 75 °. The second support angle θ ₂ is preferably 65
It is recommended to set the angle between 70 ° and 70 °.

The transport path 30 connects the lower end portion 10a of the first supporting means 10 and the lower end portion 20a of the second supporting means 20,
A path for transporting the recording medium P extending from the rear part to the front part of the main body 1 is configured. The transport path 30 is separated from the rear portion (upstream side) to the front portion (downstream side) in order.
1, pre-transfer guides 32a and 32b, post-transfer guide 33
a, 33b, and the reverse guide 34 on the downstream side of the fixing unit 70. Also, diagonally above the separation pad 31,
A paper feed roller 35 is arranged, and a conveyance roller 36 is arranged below the paper feed roller 35. Paper feed roller 35
Has an outer peripheral surface eccentrically formed with respect to the shaft 35a, and is rotated in the direction of arrow R35 so that the first support means 10
The uppermost recording medium P is fed from the above to prevent the double feeding of the recording medium P between the separation roller 31 and the conveyance roller 36.
Together with this, the recording medium P is configured to be conveyed. The pre-transfer guide 32a on the upstream side is configured to move gently downward, and the pre-transfer guide 32b on the downstream side is configured to be substantially horizontal, and the lower surface 4 of the upper process cartridge 40 is formed.
0a to guide the recording medium P to the photosensitive drum 41
And the transfer roller 61 of the transfer unit 60. The post-transfer guide 33a is formed on the inclined surface which is inclined downward to the front, and the post-transfer guide 3 which is continuous with this is formed.
3b has a gentle concave surface. The recording medium P after the toner image transfer is guided to the fixing position A3 formed between the fixing film of the fixing unit 70 and the pressure roller (both will be described later) by the post-transfer guides 33a and 33b. In addition, on the most upstream side of the post-transfer guide 33a, a charge removing member 33c that removes excess charges of the recording medium P after the toner image transfer is attached. The reversing guide 34 is a gently curved guide that is provided between the transport roller 37 immediately downstream of the fixing unit 70 and the paper discharge roller 38 above the transport roller 37, and guides the recording medium P after fixing the toner image upward. Guide toward the second support means 20. In addition, this inversion guide 34
Is integrally formed with the exterior cover 2 described above.

As described above, the feeding position A1, the transfer position A2, and the fixing position A are sequentially arranged in this conveying path 30 from the upstream side.
3 are provided, but these positions A1, A2, A3
Are set to be sequentially arranged in this order at lower positions. Therefore, at the time of image formation, these positions A1,
The recording medium P that sequentially passes through A2 and A3 is at a high place (A1).
Therefore, the sheets are sequentially conveyed to a low place (A3), and smooth conveyance is performed according to gravity. Furthermore, since the leading end of the recording medium P at this time is supported from below by the pre-transfer guides 32a, 32b and the post-transfer guides 33a, 33b, these guides 32a, 32b, 33a, 33 are provided.
Following b, the paper is conveyed in a stable posture. For this reason, it is surely introduced into the transfer position A2 and the fixing position A3, and the conveyance failure such as paper jam is well prevented.

In the process cartridge 40, a photosensitive drum 41, a charging roller (charging means) 42, a developing device (developing means) 43, and a cleaning device (cleaning means) 44 are integrated into a cartridge container 45 to form a cartridge. It is detachable from the main body 1. The photosensitive drum 41 is a drum-shaped electrophotographic photosensitive member as described above, and includes a motor 84 (described later) on the main body 1 side.
Is driven to rotate in the direction of arrow R41. The charging roller 42 is disposed in contact with the surface of the photosensitive drum 41, and is driven to rotate as the photosensitive drum 41 rotates in the direction of arrow R41. A charging voltage in which a DC voltage and an AC voltage are superposed is applied to the charging roller 42 by the high voltage generating unit 83 on the substrate 80 on the main body 1 side, and the rotation of the photosensitive drum 41 causes the surface of the photosensitive drum 41 to move. It is uniformly charged. The developing device 43 has a toner container 43a for containing toner and a developing sleeve 43b. The developing sleeve 43b has a magnet inside and carries toner on the surface by rotating. The layer thickness of the toner on the surface is regulated by the regulation blade 43c and an electric charge is applied to the toner, and the toner is attached to the electrostatic latent image formed on the photosensitive drum 41 by the information light emitting unit 50, which will be described later.
Form a toner image. In the process cartridge 40 according to the present embodiment, the developing device 43 can arrange the toner container 43a on the upper side and the developing sleeve 43b on the lower side. Therefore, the toner in the toner container 43a naturally develops due to gravity. It drops toward the sleeve 43b. Therefore, it is not necessary to attach a special mechanism for conveying the toner in the toner container 43a toward the developing sleeve 43b, such as a stirring member. As a result, the structure of the process cartridge 40 can be simplified. The cleaning device 44 includes a cleaning blade 44a that rubs the surface of the photosensitive drum 41 after the toner image transfer to remove residual toner on the surface, and a cleaning container 44b that collects the removed waste toner. A through hole 45a for exposure is formed in the upper portion of the cartridge container 45. The operation of attaching / detaching the process cartridge 40 to / from the main body 1 will be described later.

The information light emitting means 50 irradiates the surface of the photosensitive drum 41 with light through the above-described through hole 45a for exposure, and is arranged above the process cartridge 40 as a whole. The information light emitting means 50 includes a semiconductor laser 55 that oscillates a laser beam based on an image signal, and a polygon mirror 51 that reflects the laser beam while rotating it.
And a motor 52 for rotating the polygon mirror 51,
The lens 53 and the reflection mirror 54 are provided. The information light emitting means 50 includes a polygon mirror 51 and a first supporting means 1.
The reflecting mirror 54 is disposed on the 0 side (rear side) and downward, and on the second supporting means 20 side (front side) and upward. In other words, the whole is arranged in the front upward direction, contrary to the above-mentioned transport path 30. By arranging in this way, it is possible to prevent the height of the main body 1 from becoming high, and in a compact configuration, the required optical path length of the laser beam from the polygon mirror 51 to the photosensitive drum 41 via the reflection mirror 54 is reduced. It is possible to secure the position and to set the mounting position of the manual insertion guide 13a of the first supporting means 10 to a position where operability is good. By the irradiation of this laser beam, the photosensitive drum 41
An electrostatic latent image corresponding to the image signal is formed on the top.

The process cartridge 40 and the information light emitting means 50 described above are arranged between the rear first supporting means 10, the front second supporting means 20, and the lower conveying path 30, that is, a vertical U-shaped path. It is compactly placed in the inner space.

The transfer means 60 includes a transfer roller 61 which is in contact with the photosensitive drum 41 from below under the transport path 30.
And a transfer position A2 is formed between the photosensitive drum 41 and the photosensitive drum 41. The left and right ends of the cored bar 61a of the transfer roller 61 are respectively held by bearings 63 urged by springs 62, so that the transfer roller 61 is brought into contact with the surface of the photosensitive drum 41 with a predetermined pressing force. A transfer voltage having a polarity opposite to that of the toner image on the photosensitive drum 41 is applied to the transfer roller 61 by the high-voltage generating unit 83 on the substrate 80.
The toner image on the photosensitive drum 41 is transferred onto the surface of the recording medium P passing through the transfer position A2. The transfer means 60 will be described later together with the contact / separation mechanism for contacting and separating the transfer means 60 with the photosensitive drum 41.

The fixing means 70 includes a ceramic heater 72 held by the main body 1 via a spring 71, a fixing film 74 endlessly mounted on the outer periphery of a guide 73, and a fixing film 74 which is in contact with the fixing film 74 from below. It has a pressure roller 75 that forms a fixing position A3 with the film 74. Since the ceramic heater 72 and the fixing film 74 have small heat capacities, it takes a short time to heat up to a predetermined temperature required for fixing after energization. This prevents unnecessary heat from being radiated from the fixing means 70. The fixing unit 70 melts and fixes the toner image when the recording medium P having the toner image transferred on the surface at the upstream transfer position A2 passes the transfer position A3 while carrying the unfixed toner image. And is fixed on the surface of the recording medium P.

The lower part of the main body 1, that is, the above-mentioned transport path 30.
A substrate 80 is disposed below the substrate. A control unit 81, an AC input unit 82, a high voltage generation unit 83, and a motor 84 are arranged on the substrate 80 in this order from the downstream side (front side).
The heights of these are gradually increasing in this order.
That is, among the members on the substrate 80, tall members are arranged at the rear part and short members are arranged at the front part. This is consistent with the configuration of the transport path 30 described above, where the rear side is high and the front side is low. That is, the arrangement of each member on the substrate 80 is determined according to the space below the transport path 30. This contributes to downsizing of the main body 1.

Next, the image forming operation of the entire printer M having the above configuration will be briefly described.

First, the recording medium P is set on the first supporting means 10 in the vertical direction. The photosensitive drum 41 in the process cartridge 40 is rotationally driven, and by the charging roller 42,
The surface of the photosensitive drum 41 is uniformly charged with, for example, a negative polarity.
The information light emitting means 50 exposes the uniformly charged surface of the photosensitive drum 41. Laser light based on an image signal is emitted from the information light emitting means 50 to irradiate the surface of the photosensitive drum 41. Negative charges are removed from the light-irradiated portion on the photosensitive drum 41 to form an electrostatic latent image. This electrostatic latent image becomes a toner image by so-called reversal development in which toner of negative polarity is attached by the developing device 43.
On the other hand, the recording medium P, which has waited with its leading end aligned with the sheet feeding position A1, is supplied to the transfer position A2 by the sheet feeding roller 35 so as to match the timing with the toner image on the photosensitive drum 41. At the transfer position A2, by the transfer roller 61 to which a transfer voltage having a positive polarity opposite to that of the toner is applied,
The toner image on the photosensitive drum 41 is transferred onto the recording medium P. In the fixing means 70, the unfixed toner image on the surface of the recording medium P is fixed by being heated and pressed. The recording medium P on which the toner image has been fixed is vertically ejected onto the second supporting unit 20 by the paper ejection roller 38 via the reversing path 34.

In the printer M of this embodiment, the recording medium P before the image formation and the recording medium P after the image formation are respectively supported by the first supporting means 10,
The occupied area of the main body 1 is reduced by vertically supporting the second support means 20 and shortening the transport path 30.

Next, the structure for supporting the process cartridge 40 in the main body 1, the method for attaching / detaching the process cartridge 40, and the contact / separation mechanism for retracting the transfer means 60 from the photosensitive drum 41 at the time of attachment / detachment will be described.

FIG. 2 is a diagram schematically showing a vertical cross section of the process cartridge 40 and the contact / separation mechanism 90. The shape and configuration of the process cartridge 40 shown in the figure is slightly different from that of the process cartridge 40 shown in FIG.
The configuration of the process cartridge 40 will be briefly described with reference to FIG. The process cartridge 40 is configured by integrally incorporating a photosensitive drum 41, a charging roller 42, a developing device 43, and a cleaning device 44 in a cartridge container 45. The photosensitive drum 41 is rotatably supported by a cartridge container 45 in a direction of an arrow R41, and the developing device 43 includes a toner container 43 for storing toner.
The cleaning device 44 has a cleaning sleeve 4b for removing the residual toner on the photosensitive drum 41.
4a and cleaning container 4 for collecting the removed waste toner
4b and. Further, a through hole 45a for exposure is provided in the center of the upper portion of the cartridge container 45, and positioning ribs 45b and 45c are provided at the front end portion and the rear end portion, respectively. These positioning ribs 45b, 45c
Are formed to be long in the left-right direction.

As shown in FIG. 2, guides (cartridge supporting means) 1b and 1c for supporting the positioning ribs 45b and 45c are formed on the main body 1 side. The guides 1b and 1c are formed to be long in the left-right direction, and the process cartridge 4 is provided via the positioning ribs 45b and 45c.
5 is supported so as to be movable in the left-right direction. In the figure, L
Indicates laser light emitted from the information light emitting means 50 and irradiating the surface of the photosensitive drum 41.

Process cartridge 4 when mounted on the main body 1
0 of the photosensitive drum 41, the transfer roller 6 of the transfer means 60
1 is abutted from below to form a transfer position A2 with the photosensitive drum 41. Below the photosensitive drum 41 in the transport path 30, a box-shaped lifting guide 1 that is long in the left-right direction is provided.
a is formed. The transfer means 60 is restricted from moving in the front-rear direction and the left-right direction by the elevating guide 1a, and is allowed to move only in the up-down direction. The transfer means 60 is disposed in the upper half of the elevating guide 1a, and the lower half of the elevating guide 1a, that is, below the transfer means 60, is provided with a push-up member 91 forming a part of the contacting / separating means 90. Has been done.

Referring to the front view of FIG. 4, the transfer means 60,
The contact / separation mechanism 90 and the like will be described in more detail. Transfer means 60
Has a transfer roller 61. The transfer roller 61 is rotatably supported by bearings 63, 63 at both left and right ends of a cored bar 61a. These bearings 63, 63 are biased upward by springs 62, 62 interposed between the bearings 63, 63 and a holder (bearing member) 64. As a result, the entire transfer roller 61 is pressed against the surface of the upper photosensitive drum 41 with an appropriate force. The holder 64 is supported movably up and down by the aforementioned elevating guide 1a, and there are two inclined surfaces (engaging portions) 6 on the lower surface near the left and right ends, respectively.
4a and 64a are provided. These inclined surfaces 64a, 64
a is a contacting / separating mechanism 9 together with a push-up member 91 described below.
Configure 0.

The contact / separation mechanism 90 is a push-up member 9 disposed below the transfer means 60 in the lift guide 1a.
Has 1. The push-up member 91 is formed to be long in the left-right direction, and its position in the front-rear direction is regulated by the elevating guide 1a and is supported so as to be movable in the left-right direction. Near the left and right ends of the upper surface of the push-up member 91, inclined surfaces 91a and 91a that can be engaged with and disengaged from the inclined surfaces 64a and 64a of the holder 64, respectively, are formed, and the upper surfaces of these inclined surfaces 91a and 91a are continuous with each other. Thus, the substantially horizontal support surfaces 91b, 91b are formed. Figure 4
As shown in FIG.
When the upper transfer unit 60 is supported from below by a, the transfer unit 60 is located at the operating position where the transfer roller 61 is pressed against the photosensitive drum 1. The compression spring 92 is attached to one end portion (left end portion in the figure) 91c of the push-up member 91.
Is attached, so that the entire push-up member 91 is
In the figure, it is biased to the right. An opening 1d for attaching / detaching the process cartridge 40 to / from the inside of the main body 1 is provided on one side surface (right side in the figure) of the main body 1, and the opening 1d is used for opening and closing the opening 1d. The opening / closing member 1e is attached (see FIG. 6). As shown in FIG. 3, when the opening / closing member 1e is closed, the push-up member 91 biased to the right by the compression spring 92 has an end 91d on the opposite side of the compression spring 92 from the opening / closing means 1e.
The entire position is regulated by making contact with the abutting portion 91f.

Next, the attaching / detaching operation of the process cartridge 40 and the contact / separation operation of the transfer means 60 by the contact / separation means 90 will be described with reference to FIGS.

As shown in FIG. 4, when the process cartridge 40 is mounted on the main body 1 and the opening / closing member 1e is closed, the push-up member 91 is moved by the opening / closing member 1e.
It is pushed to the left against the compression spring 92. At this time, the push-up member 91 is moved by the supporting surfaces 91b and 91b.
0 is pushed from below, whereby the transfer means 60 is
The transfer roller 61 is arranged at an operating position where it abuts on the photosensitive drum 41.

When the opening / closing member 1e is opened to take out the process cartridge 40 from the main body 1 (dotted line in FIG. 4,
5 and 6), the push-up member 91 is a compression spring 92.
Is moved to the right (FIG. 5) by this, the inclined surfaces 64a, 64a on the holder 64 side slide down along the inclined surfaces 91a, 91a on the push-up member 91 side, and the entire transfer means 60 descends and is placed in the retracted position. To be done. Therefore, an appropriate gap G is formed between the transfer roller 61 and the photosensitive drum 41 of the upper process cartridge 40.

Subsequently, the entire process cartridge 40 is slid to the right along the guides 1b and 1c and taken out from the opening 1d. At this time, since the transfer roller 61 is separated from the photosensitive drum 41 on the process cartridge 40 side, the take-out operation can be smoothly performed without damaging the surface of the photosensitive drum 41 or the transfer roller 61.

On the other hand, when the process cartridge 40 is mounted, the opening / closing member 1e is opened prior to the mounting of the process cartridge 40, and in conjunction with this, the transfer means 60 is arranged at the retracted position via the push-up member 91, and the above-mentioned gap G is formed. Reserved. Therefore, at the time of mounting, the process cartridge 40 can be easily mounted by sliding it to the left in FIG. 5 along the guides 1b and 1c. When the opening / closing member 1e is subsequently closed, the opening / closing member 1e moves the push-up member 91 to the left, and the inclined surfaces 64a, 64a on the holder 64 side.
Are pushed upward along the inclined surfaces 91a, 91a on the push-up member 91 side, and the holder 64 is entirely supported by the support surface 9a.
It is supported by 1b and 91b. As a result, the entire transfer unit 60 is arranged at the operating position where the transfer roller 61 contacts the photosensitive drum 41.

As described above, the process cartridge 40
When the opening / closing member 1e is opened at the time of attachment / detachment, the transfer means 60 is lowered to the retracted position via the push-up member 91, and the transfer roller 61 is separated from the photosensitive drum 41, in conjunction with this. On the other hand, when the opening / closing member 1e is closed, it interlocks with this,
The transfer unit 60 is pushed up to the operating position via the push-up member 91, and the transfer roller 61 contacts the photosensitive drum 41.
Therefore, inside the main body 1, the process cartridge 4
There is no need to provide an extra portion for attaching and detaching 0, dead space is eliminated, and the mounting density of each member is increased.
It is possible to realize the miniaturization of. <Second Embodiment> In the above embodiments, the information light emitting means 5 is used.
As 0, instead of emitting a laser beam, L
It is also possible to use an ED array. Photosensitive drum 41
By arranging a large number of LEDs along the generatrix of the surface of the photosensitive drum 41 and rotating the charged photosensitive drum 41, ON / OFF of each LED is selected on the basis of an image signal. It forms an electrostatic latent image on it. According to this, the configuration can be further downsized and simplified. <Embodiment 3> The members of the process cartridge 40 described above are not limited to those shown in FIG. For example, an electrophotographic photosensitive member as an image carrier and at least one of a charging unit, a developing unit, and a cleaning unit as a process unit are integrally made into a cartridge and detachable from the main body of the image forming apparatus. May be.

Further, the electrophotographic photosensitive member as the image carrier and the charging means, the developing means or the cleaning means as the process means are integrally made into a cartridge, and this cartridge can be attached to and detached from the main body of the image forming apparatus. Alternatively, at least the developing means and the electrophotographic photosensitive member as the image bearing member may be integrally formed into a cartridge so as to be detachable from the main body of the image forming apparatus. <Embodiment 4> The first supporting means 10 of the above embodiments may be configured mainly by a paper feed cassette. A vertical cassette mounting portion is provided at the rear portion of the main body 1, and a paper feed cassette containing the recording medium P is mounted from above the cassette mounting portion to support the recording medium P in the vertical direction. is there. In this case, the cassette mounting portion and the paper feed cassette constitute the first supporting means.

[0050]

As described above, according to the present invention,
Supports the recording medium before and after image formation in the vertical direction,
Further, by shortening the transport path, the area occupied by the apparatus body can be reduced.

Further, the process cartridge is attached / detached to / from the apparatus main body from the left and right, and the transfer means is separated from the image carrier of the process cartridge at the time of attachment / detachment, thereby providing a margin for attachment / detachment inside the apparatus main body. There is no need, and the miniaturization of the device body can be realized.

[Brief description of drawings]

FIG. 1 is a vertical cross-sectional view illustrating a schematic configuration of an image forming apparatus according to a first exemplary embodiment.

FIG. 2 is a process cartridge of Example 1, a transfer unit,
The figure which shows the structure of a contact / separation mechanism typically.

FIG. 3 is a vertical cross-sectional view showing the configuration of the process cartridge according to the first embodiment.

FIG. 4 is a front view of the first embodiment, showing a state in which a transfer unit is arranged at an operating position by a contact / separation mechanism.

FIG. 5 is a front view of the first embodiment, showing a state in which a transfer unit is arranged at a retracted position by a contact / separation mechanism.

FIG. 6 is a perspective view showing a state in which the opening / closing member of the first embodiment is opened.

[Description of Reference Signs] 1 main body of image forming apparatus (printer main body) 1a elevating guide 1b, 1c guide (cartridge supporting means) 1d opening 1e opening / closing member 1f abutting portion 10 first supporting means 20 second supporting means 30 transport path 40 Process cartridge 41 Image carrier (photosensitive drum) 42 Charging means (transfer roller) 43 Developing means (developing device) 44 Cleaning means (cleaning device) 45 Cartridge containers 45b, 45c Positioning ribs 50 Information light emitting means 51 Polygon mirror 60 Transfer means 61 Transfer roller 62 Spring 63 Bearing 64 Bearing member (holder) 64a Inclined surface (engagement part) 70 Fixing means 80 Substrate 90 Contact / separation mechanism 91 Push-up member 91a Inclined surface 91b Support surface 92 Compression spring A1 Feed position A2 Transfer position A3 Fixing position M Image forming device The beam printer) P recording medium theta ₁ first supporting angle theta ₂ second supporting angle

Claims (10)

[Claims] 1. An image forming apparatus for forming an image on a recording medium, comprising: first supporting means for vertically supporting a recording medium for feeding; and second supporting means for vertically supporting the recording medium after image formation. Between a supporting means, a detachable process cartridge having an image carrier provided above a conveying path from the first supporting means to the second supporting means, and between the first supporting means and the second supporting means. And an information light emitting unit provided above the process cartridge for giving information light corresponding to image information to the image carrier, and an image light carrier provided below the transport path. Transfer means for transferring the formed toner image to the recording medium, fixing means for fixing the toner image transferred on the recording medium to the recording medium, and movable in the left-right direction in the conveying direction of the recording medium To the above The cartridge supporting means on the apparatus main body side for supporting the access cartridge and the transfer means can be moved to an operation position where the transfer means contacts the image carrier and a retracted position where the transfer means separates from the image carrier. An image forming apparatus comprising: a contacting / separating mechanism that supports the image forming apparatus. 2. The apparatus main body has an opening for attaching / detaching the process cartridge on the side of the apparatus main body, and an opening / closing member for opening / closing the opening, and the contact / separation mechanism is provided for the opening / closing member. The image forming apparatus according to claim 1, wherein the transfer means is arranged in the operating position in correspondence with a closed state, and the transfer means is arranged in the retracted position in correspondence with an open state of the opening / closing member. apparatus. 3. The transfer means has a bearing member that rotatably supports the transfer roller and is movably supported by the apparatus main body, and the contacting / separating mechanism is disposed below the bearing member. A push-up member that moves in the lateral direction in conjunction with the opening / closing operation of the open / close member, an inclined surface is formed on one of the lower surface of the bearing member and the upper surface of the push-up member, and the inclined surface is formed on the other side. The engaging portion that engages and disengages is provided, and the lateral movement of the push-up member is converted into an elevating operation of the push-up member by sliding friction between the inclined surface and the engagement portion. Image forming apparatus. 4. A feeding position for feeding the recording medium supported by the first supporting means, a feeding position for feeding the recording medium supported by the first supporting means, a transfer position by the transferring means, and the fixing means, which are sequentially arranged from the upstream side to the downstream side of the conveying path. The image forming apparatus according to claim 1, wherein the fixing position by the means is sequentially arranged at a lower position in this order. 5. The image forming apparatus according to claim 1, wherein the information light emitting means emits a laser beam. 6. The information light emitting means includes a semiconductor laser, a polygon mirror, a lens, and a reflection mirror, and the polygon mirror is supported on the side of the first supporting means and the reflection mirror is supported on the second side. 6. The image forming apparatus according to claim 5, wherein the image forming apparatus is arranged on the device side, and the polygon mirror is arranged below and the reflection mirror is arranged above. 7. The image forming apparatus according to claim 1, wherein the information light emitting unit has an LED array arranged so as to face the image carrier. 8. The image carrier comprises an electrophotographic photosensitive member as the image carrier and at least one of a charging unit, a developing unit, and a cleaning unit, which are integrally formed as a cartridge with respect to the main body of the image forming apparatus. The image forming apparatus according to claim 1, wherein the image forming apparatus is provided in a process cartridge that is detachable. 9. The image carrier can be attached to and detached from an image forming apparatus main body by integrally forming an electrophotographic photosensitive member as the image carrier and a charging unit, a developing unit, or a cleaning unit into a cartridge. The image forming apparatus according to claim 1, wherein the image forming apparatus is provided in the process cartridge. 10. The image carrier is provided in a process cartridge in which at least a developing unit and an electrophotographic photosensitive member as the image carrier are integrally made into a cartridge so as to be attachable to and detachable from an image forming apparatus main body. The image forming apparatus according to claim 1, wherein: