JP2002356245A - Image forming device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve operability in dealing with paper jam by contriving a construction of a conveying system conveying paper sheets to a transferring and a fixing system in time series. SOLUTION: This image forming device is provided with a device main body A, image carrying bodies 1Y, 1M, 1C, 1K forming an electrostatic latent image, developing means 4Y, 4M, 4C, 4K making the electrostatic latent image on the image carrying bodies a visible toner image with developer, transferring means 5A, 5Y, 5M, 5C, 5K transferring the toner image made visible on the image carrying bodies with the developer onto a paper sheet P, a fixing means 24 fixing the toner image transferred on the paper sheet by the transferring means, and a conveying stand 9 conveying and feeding the paper sheet P to the image carrying bodies, the transferring means, and the fixing means. The conveying stand 9 has a structure at least independent from the image carrying bodies and capable of being drawn out from the inside of the device main body to a designated outside position.

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 using an electrophotographic method, such as a copying machine, a printer, and a facsimile, and more particularly, to a method for forming a plurality of images by using a plurality of image carriers, a latent image forming means, and a developing means. The present invention relates to a tandem type color image forming apparatus for transferring a toner image formed on a carrier to an intermediate transfer member.

[0002]

2. Description of the Related Art In recent years, a color image forming apparatus using an electrophotographic system has often been used. According to this type of image forming apparatus, a plurality of image forming units are arranged in parallel in a sheet conveying direction, and toner images of different colors formed on photosensitive drums in the image forming units are held on a conveying belt. Are sequentially transferred onto the printed paper.

A color image forming apparatus using a transfer drum instead of a transport belt is also known. A sheet fed from a paper feeding unit is wound around a transfer drum, and then the sheet wound around the transfer drum is used. Then, a toner image visualized by the developing means is sequentially transferred to form a full-color image on the sheet. Then, the sheet is separated from the transfer drum, and after the toner image is fixed by the fixing unit, the sheet is discharged.

[0004] In still another color image forming apparatus,
After arranging a plurality of image forming sections in parallel in the transport direction and sequentially transferring toner images of different colors formed on the photosensitive drums in the image forming sections onto an intermediate transfer body to form a primary transfer image in a superimposed manner A so-called tandem system in which this primary transfer image is secondarily transferred onto a recording medium held on a transport belt has also been proposed.

Such a tandem-type color image forming apparatus forms a color image by rotating a single photoconductor a plurality of times in order to simultaneously form images of different colors on a plurality of photoconductors. A full-color image can be output at a higher speed than a color image forming apparatus. Further, these image forming apparatuses are provided with a sheet conveying means, and convey the sheet under the image forming section with good timing.

[0006]

According to the conventional image forming apparatus, the paper conveying means is divided for each mechanism block, such as a conveying belt and a conveying roller, in order to cope with a paper jam or the like. During processing, the mechanism block is partially taken out to the outside. However, there are the following problems.

If a jammed sheet straddles a plurality of mechanism blocks, and if the jammed paper is held in one mechanism block, and the other mechanism block is pulled out to the outside, the sheet May be disconnected. Further, in such a case, it takes much time and effort to remove the cut sheet, and the operability at the time of jam clearance is reduced, which hinders smooth maintenance. Incidentally, there has been proposed an image forming apparatus in which a plurality of photoconductors, an intermediate transfer member, a plurality of developing means, and the like are integrated into one process platform, and the process platform can be taken out to the front side. In the case where the paper transport unit is configured to be drawn out of this type of image forming apparatus without any contrivance, the weight of the process stand and the weight of the paper transport unit may cause the apparatus body to fall to the front side.

In view of the above, the present invention has been made to solve the above-mentioned problems, and has improved the operability during jam clearance by devising the structure of a paper transport system for transporting and passing recording paper to a transfer / fixing system. It is another object of the present invention to provide an image forming apparatus capable of ensuring the safety of the image forming apparatus.

[0009]

In order to solve the above-mentioned problems and to achieve the object, a first image forming apparatus according to the present invention comprises an apparatus main body, an image carrier for forming an electrostatic latent image, and Developing means for visualizing the electrostatic latent image on the image carrier with a developer to form a toner image, and transferring means for transferring the toner image on the image carrier visualized by the developing means to recording paper Fixing means for fixing the toner image on the recording sheet transferred by the transfer means, and a transfer stand having a paper feed port for conveying and passing the recording sheet to the transfer means, the transfer stand being The portion from the paper feed port of the transfer stand to the transfer position is longer than the maximum length of recording paper handled by the device, and has a structure that can be pulled out from the inside of the device main body to a predetermined external position. It is characterized by the following.

For example, in the first image forming apparatus, the transport frame has a paper feed port and a paper discharge port, and temporarily stops the recording paper taken in from the paper feed port, and transfers the recording paper to the transfer unit at a predetermined timing. A feed roller for feeding, a manual paper feed path for feeding the recording paper stored in the manual feed tray to the transfer means, and a cassette for feeding the recording paper stored in the paper feed cassette to the transfer means Paper feed path, a paper discharge path for passing the recording paper on which the toner image is fixed through the paper discharge port and discharging the recording paper to the outside of the apparatus main body, and a transfer unit for transferring the recording paper fed by the transport roller. And a transfer roller for pressing the toner image.

According to the first image forming apparatus of the present invention, the first image forming apparatus has such a size that the recording paper of the maximum length handled by the apparatus can be almost taken in from the paper feed port to the transfer position, and If there is no paper jam on the premise that a transport gantry having a structure that can be pulled out from the inside of the apparatus main body to a predetermined position outside is provided. Are passed in chronological order and conveyed to a paper discharge port.

During this time, an electrostatic latent image is formed by the image carrier, and the developing device visualizes the electrostatic latent image on the image carrier with a developer to form a toner image. In the transfer unit, the toner image on the image carrier that has been visualized by the developing unit is transferred to recording paper by the transfer unit. Thereafter, the toner image on the recording paper transferred by the transfer unit is fixed by the fixing unit.

When a paper jam occurs, the transport gantry is pulled out from the inside of the apparatus main body to a predetermined external position. Therefore, most of the paper feed path that is expected to be jammed with recording paper can be taken out of the main unit.
The transport gantry was pulled out from the inside of the apparatus body to a predetermined external position, such as the state of arrival of the recording sheet at the transfer unit and the state of arrival of the recording sheet at the fixing unit between the paper feed port and the discharge port of the transport gantry. In this state, paper jam processing can be performed smoothly.

A second image forming apparatus according to the present invention comprises an apparatus main body, a plurality of image carriers for forming an electrostatic latent image, and developing means for developing the electrostatic latent image into a toner image by developing the image with a developer. A process frame that can be pulled out to the apparatus main body, a transfer unit that transfers the toner image on the image carrier visualized by the developing unit to a recording sheet, and a transfer unit that transfers the toner image on the recording sheet transferred by the transfer unit. A fixing unit for fixing the toner image, and a transfer stand for conveying and passing the recording paper to the transfer unit and the fixing unit, and the transfer stand or the process stand is selected based on an operation of selecting one of the process stand and the transfer stand. And a gantry releasing mechanism for fixing the pull-out operation.

According to the second image forming apparatus of the present invention, there is provided a gantry releasing mechanism for fixing the pull-out operation of the transfer gantry or the process gantry based on the operation of selecting one of the process gantry and the gantry. On the premise of this, if there is no paper jam, the image carrier, the transfer means and the fixing means are passed in time series from the paper feed port by the transport stand and conveyed to the paper discharge port.

During this time, an electrostatic latent image is formed by the image carrier, and the developing device visualizes the electrostatic latent image on the image carrier with a developer to form a toner image. In the transfer unit, the toner image on the image carrier that has been visualized by the developing unit is transferred to recording paper by the transfer unit. Thereafter, the toner image on the recording paper transferred by the transfer unit is fixed by the fixing unit. Further, when a paper jam occurs, the operation of pulling out the process gantry is fixed by the gantry release mechanism based on the operation of selecting the drawer of the transport gantry.

Therefore, since either the process gantry or the transport gantry can be pulled out, the process gantry and the transport gantry are not simultaneously pulled out. As a result, one of the process stand and the transfer stand remains in the apparatus main body, so that the apparatus main body can be prevented from tipping over due to a weight balance collapse.In addition, since the process stand and the transfer stand are not pulled out at the same time, both sides are eliminated. It is also possible to prevent the parts from contacting and breaking.

[0018]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, an image forming apparatus according to an embodiment of the present invention will be described with reference to the drawings. (1) First Embodiment FIG. 1 is a schematic cross-sectional view illustrating a configuration example of an image forming apparatus 100 according to a first embodiment of the invention. FIG. 2 is a sectional view showing a configuration example of the process base 8. In this embodiment, the image carrier, the transfer unit, and the fixing unit are provided with a transport gantry for transporting and passing the recording paper in chronological order. When the paper jam occurs, the recording paper reaches the transfer means between the paper feed port and the paper discharge port of the transport stand, and the recording paper reaches the fixing means. Operability can be improved.

The image forming apparatus 100 shown in FIG. 1 is referred to as a tandem type color image forming apparatus. A process stand 8 for image formation and a recording paper transport are provided in an image forming apparatus main body (hereinafter referred to as an apparatus main body) A. Transport gantry 9 is provided. A plurality of image forming units 10 are mounted on the process base 8.
Y, 10M, 10C, and 10K, and an intermediate transfer unit 7 are provided. A document image reading device SC is arranged on the apparatus main body A.

Image forming section 1 for forming a yellow image
Reference numeral 0Y includes a charging unit 2Y, an exposing unit 3Y, a developing unit 4Y, a primary transfer unit 5Y, and a cleaning unit 6Y arranged around the image carrier (photoconductor) 1Y. In the image forming unit 10Y, the image carrier 1Y is charged by the charging unit 2Y, and the image carrier 1Y is exposed by the exposure unit 3Y. By this exposure, an electrostatic latent image is formed on the image carrier 1Y, and the electrostatic latent image on the image carrier 1Y is visualized by the developer supplied from the developing means 4Y to form a yellow toner image. Is made.

Image forming section 1 for forming a magenta image
0M has an image carrier (photoconductor) 1M, a charging unit 2M, an exposing unit 3M, a developing unit 4M, a primary transfer unit 5M, and a cleaning unit 6M. In the image forming unit 10M, the image carrier 1M is charged by the charging unit 2M, and the exposure unit 3M is charged.
M exposes the image carrier 1M. By this exposure, an electrostatic latent image is formed on the image carrier 1M, and the electrostatic latent image on the image carrier 1M is visualized by the developer supplied from the developing unit 4M to form a magenta toner image. Is made.

Image forming section 10 for forming a cyan image
C has an image carrier (photoreceptor) 1C, a charging unit 2C, an exposing unit 3C, a developing unit 4C, a primary transfer unit 5C, and a cleaning unit 6C. In the image forming unit 10C, the image carrier 1C is charged by the charging unit 2C, and the exposure unit 3C
Thus, the image carrier 1C is exposed. With this exposure,
An electrostatic latent image is formed on the image carrier 1C.
The upper electrostatic latent image is visualized by the developer supplied from the developing unit 4C to form a magenta toner image.

The image forming section 10K for forming a black image includes:
Image carrier (photoconductor) 1K, charging unit 2K, exposure unit 3
K, a developing unit 4K, a primary transfer unit 5K, and a cleaning unit 6K. In the image forming unit 10K, the image carrier 1K is charged by the charging unit 2K, and the image carrier 1K is exposed by the exposure unit 3K. By this exposure, an electrostatic latent image is formed on the image carrier 1K, and the electrostatic latent image on the image carrier 1K is visualized by the developer supplied from the developing unit 4K to form a black toner image. Done.

This process base 8 is provided with an intermediate transfer unit 7
have. The intermediate transfer unit 7 has a semiconductive endless belt-shaped intermediate transfer body 70 that is wound around a plurality of rollers and rotatably supported. Image forming unit l
The images of the respective colors formed from 0Y, 10M, 10C, and 10K are sequentially transferred onto the rotating intermediate transfer body 70 by the primary transfer units 5Y, 5M, 5C, and 5K to form a combined color image. You.

A transport platform 9 for transporting recording paper is provided below the process platform 8, and the paper P is transported and passed through the process platform 8 in time series. A plurality of intermediate rollers 22C and 22D, a registration roller 23, a secondary transfer unit 5A, a fixing unit 24, and the like are provided in the transport gantry 9. In this example, the transport gantry 9 is unitized and united in the same manner as the process gantry 8. A sheet cassette 20, intermediate rollers 22A and 22B, and the like are provided below the transfer stand 9.

In the secondary transfer means 5A provided below the intermediate transfer unit 7, the image forming units 10Y, 10Y
Intermediate transfer member 7 visualized by M, 10C and 10K
0 is transferred to a recording sheet (hereinafter referred to as sheet P). A fixing unit 24 is provided downstream of the secondary transfer unit 5A so as to fix the transferred color image on the sheet P.

That is, the paper P stored in the paper feed cassette 20 is fed by the transport pedestal 9 and has a plurality of intermediate rollers 22A, 22B, 22C, 22D,
After that, the sheet is conveyed to the secondary transfer means 5A, and the color image is collectively transferred onto the sheet P. The paper P to which the color image has been transferred is subjected to a fixing process by the fixing unit 24, and is held by a paper discharge roller 25 and placed on a paper discharge tray 26 outside the apparatus.

On the other hand, after the color image is transferred to the sheet P by the secondary transfer means 5A, the residual toner is removed by the cleaning means 6A from the intermediate transfer body 70 from which the sheet P is separated by curvature. During the image forming process, the primary transfer unit 5K always
It is in pressure contact with the photoconductor 1K. Other primary transfer means 5Y, 5
M and 5C come into pressure contact with the corresponding photoconductors 1Y, 1M and 1C only during color image formation. Secondary transfer means 5A
Is in pressure contact with the intermediate transfer member 70 only when the paper P passes here and the secondary transfer is performed.

In the process stand 8 shown in FIG. 2, the image forming units 10Y, 10M, 10C, and 10K are vertically arranged in tandem. Image forming unit 10 of process stand 8
The outside of one end of K has an R shape. This is for matching with the partial shape of the transfer gantry 9. Photoconductors lY, 1M, 1
An intermediate transfer unit 7 is disposed on the left side of C and 1K in the figure.

In this example, the image forming units 10Y, 10M, 1
0C, 10K and the intermediate transfer unit 7 form a process base 8. The intermediate transfer unit 7 includes a roller 7
An endless belt-shaped intermediate transfer body 70 rotatable by winding around 1, 72, 73, 74, primary transfer means 5Y, 5M,
5C, 5K, and cleaning means 6A.

The process base 8 is provided with a photosensitive member 1Y, 1
M, 1C, 1K, charging means 2Y, 2M, 2C, 2K, developing means 4Y, 4M, 4C, 4K, cleaning means 6
Y, 6M, 6C, 6K and the intermediate transfer unit 7 are arranged and integrated, and can be pulled out from the apparatus main body A.

Next, the transfer frame 9 will be described.
FIG. 3 is a perspective view showing a configuration example of the transfer gantry 9 at the time of drawing. FIG. 4 is a front view showing an example of handling the lock lever 91. As shown in FIG. 3, the transfer gantry 9 has a structure that can be pulled out at least from the inside of the apparatus main body to a predetermined external position independently of the process gantry 8. In this example, a support rail (not shown) is provided between the transport gantry 9 and the apparatus main body A, a guide member is attached to the back or side surface of the transport gantry 9, and a driven wheel engaged on the support rail is provided. Can be

In the image forming apparatus 100, the front door 101 of the apparatus main body A is opened, and after the lock lever 91 is operated, the lock lever 91 is gripped and the transport base 9 is pulled out to the near side. The transport base 9 is guided by the guide member, and the driven wheels rotate on the support rails, and are pulled out forward.

By making it possible to draw out the transport path occupying most of the image forming apparatus 100 at a time, the jam can be easily removed. Here, assuming that the withdrawal distance from the apparatus body to the outside is α, and the depth of the transport gantry 9 is β, α = (0.7 to 0.7) depending on the weight of the transport gantry 9.
0.9) · β. This is because the width of the paper P is considered.

The transport gantry 9 has at least an L-shaped gantry body 92. The process stand 8 is inside the L-shaped part.
To match the outer R-shape. Intermediate transfer member 7
0 and the secondary transfer means 5A. A lock lever 91 is attached to the front of the gantry main body 92, and is operated when the process gantry 8 or the transport gantry 9 is pulled out from the inside of the apparatus main body.

In this example, the process stand 8 and the transfer stand 9
Is loaded in the apparatus main body, the lock lever 91 shown in FIG. 4A is set upright. In this position, both the process gantry 8 and the transport gantry 9 are fixed in the apparatus main body. When the lock lever 91 is tilted clockwise (rightward), only the process platform 8 can be pulled out of the apparatus main body while the transport platform 9 is fixed.

Conversely, when the lock lever 91 is tilted counterclockwise (to the left), only the transfer gantry 9 can be pulled out of the apparatus main body while the process gantry 8 is fixed (the gantry selection release mechanism). ). This mechanism will be described in a second embodiment.

Next, an example of the internal configuration of the transport base 9 will be described. FIG. 5 is a conceptual diagram showing an example of the internal configuration of the transport gantry 9. A plurality of intermediate rollers 22C and 22D, a registration roller 23, a secondary transfer unit (transfer roller) 5A, a fixing unit 24, a cassette paper feed path 95, a manual feed The paper feed path 96, the paper discharge path 97, and the reverse transport path 98 are provided. A paper feed port 93A for a cassette, a paper feed port 93B for a manual feed, and a paper discharge port 94A for discharge and a paper discharge port 94B for reversing are provided on the upstream side thereof. ing.

A registration roller 23 is mounted in the gantry main body.
Is stopped once, and the sheet P is fed to the secondary transfer means 5A at a predetermined timing. The registration roller 23 once stops the sheet P taken in from the sheet feeding port 93B through the manual sheet feeding path 96, and transfers the sheet P to the secondary transfer unit 5 at a predetermined timing.
A.

The secondary transfer means 5A is provided with a transfer roller, and the sheet P is pressed by the transfer roller against the intermediate transfer member 70 on which a color image has been formed.
The sheet P to which the color image has been transferred is sent to the fixing unit 24, and after being fixed by the fixing unit 24, reaches the discharge port 94A through the discharge path 97. The paper is discharged outside the main body.

In this example, the leading end of the cassette paper feeding path 95,
In other words, when the length from the cassette paper feed port 93A to the registration roller 23 is M, and the maximum length of the paper P on which an image can be formed is N, the relationship of M ≧ N is established. Thus, the sheet P from the leading end to the trailing end, which is sent from the sheet feeding cassette 20 to the transport gantry, can be taken in over the entire length without straddling the intermediate rollers 22A and 22B in the main body device. It is possible to prevent the paper P having a paper jam caused by the registration rollers 23 or the like from being cut, and to easily perform the jam processing.

The registration rollers 2 are fed from the leading end of the manual paper feed path 96, that is, from the manual paper feed port 93B.
3, the length of the sheet P on which the image can be formed.
The relationship of L ≧ N holds when the maximum length of N is N.

Thus, the paper P from the front end to the rear end sent out from the manual feed tray into the transport gantry can be taken into the transport gantry over the entire length. In addition, the transport gantry 9 can be pulled out from the inside of the apparatus main body to easily perform the jam processing. It is possible to prevent the paper P that has been jammed by the registration roller 23 or the like from being cut, and maintenance is facilitated.

In this example, the transport gantry 9 has a reversing paper feed path 98 for reversing the paper P on which an image is formed on one side.
The sheet P is again fed under the process base 8.

In this example, a timing roller 99 is provided upstream of the junction of the cassette paper supply path 95 and the manual paper supply path 96 to temporarily stop the paper P inverted by the reverse paper supply path 98. When the length from the timing roller 99 to the tip of the reversing sheet feeding path 98 is X, and the maximum length of the sheet P on which an image can be formed is N, the relationship of X ≧ N is established. .

Thus, the sheet P from the leading end to the trailing end, which has been inverted by the inverting sheet feeding path 98, can be taken into the transport frame over the entire length. In addition, the transport gantry 9 can be pulled out from the inside of the apparatus main body to easily perform the jam processing. It is possible to prevent the paper P that has caused a paper jam by the timing roller 99 or the like from being cut, thereby facilitating maintenance.

Next, a description will be given of a route release mechanism in the transport gantry 9. FIG. 6 is a conceptual diagram illustrating a configuration example of a path release mechanism in the transport gantry 9. A first path release mechanism 911 is provided above the cassette paper supply path 95 and the manual paper supply path 96 in the transport base 9 shown in FIG. This mechanism 911 is provided with an opening 901 for inspection in advance above the transfer stand 9, and this opening 901 is provided.
Cover 902 is closed so as to cover.

The transport platform 9 has the above-described paper discharge path 9.
A second path release mechanism 912 is provided below the feed path 7 and the reverse sheet supply path 98. The mechanism 912 includes
An opening 903 for inspection is provided in advance at the bottom of the camera, and the back cover 904 is closed so as to cover the opening 903.

At the time of jam clearance, first, the transport gantry 9 is pulled out of the apparatus, and then the lid 902 of the path release mechanism 911 or the back lid 904 of the path release mechanism 912 is opened. Thus, the paper P on the cassette paper feed path 95 or the manual paper feed path 96 or the paper P on the paper discharge path 97 or the reverse paper feed path 98 that is jammed can be removed.

As described above, according to the color image forming apparatus 100 according to the first embodiment of the present invention, the frame base 92 depending on the maximum length of the sheet P is provided, and is independent of the process table 8. Then, the transport gantry 9 can be pulled out from the inside of the apparatus main body to a predetermined external position.

Therefore, when a paper jam occurs, most of the cassette paper feeding path 95 where the paper P is expected to be jammed can be taken out of the main unit, so that the paper feeding port 93A of the transport base 9 is connected to the paper discharging port 94A. The paper jam processing is performed in a state in which the transport base 9 is pulled out from the inside of the apparatus main body to a predetermined external position, such as the state of arrival of the sheet P at the secondary transfer unit 5A and the state of arrival of the sheet P at the fixing unit 24. It can be performed smoothly and with good operability.

Further, according to the first embodiment, the maximum length of the sheet P on which an image can be formed is determined based on the cassette feeding path 9.
5, the manual paper feed path 96, the reverse paper feed path 98, and the like, the transport base 9 is manufactured, so that the paper P from the front end to the rear end is taken into the transport base over the entire length. be able to. Therefore, compared to the transport gantry whose length is not specified, the jammed paper is not cut when the transport gantry 9 is pulled out.

(2) Second Embodiment FIG. 7 is a perspective view showing a configuration example of a color image forming apparatus 200 as a second embodiment according to the present invention. FIG. 8 is a side view of a partly crushed color image forming apparatus 200 showing an example of a mounting position of the gantry selection release mechanism 40.

In this embodiment, a gantry selection release mechanism 40, which is an example of a gantry release mechanism, is provided so that either the process gantry 8 or the transport gantry 9 can be selected and pulled out. In this color image forming apparatus 200, the process stand 8 and the transfer stand 9 cannot be pulled out at the same time to prevent the apparatus main body A from falling due to the weight balance collapse, or the process stand 8 and the transfer stand 9 are pulled out at the same time. In this state, it is possible to prevent the two parts from contacting each other and being damaged. The other configuration of the color image forming apparatus 200 is the first color image forming apparatus 1
Since it is the same as 00, its description is omitted.

In the color image forming apparatus 200 shown in FIG. 7, the process base 8 is pulled out from the apparatus main body A.
The process gantry 8 has a structure that can be pulled out from the inside of the apparatus body to a predetermined external position at least independently of the transfer gantry 9. The support rail 82A on the left side of the process gantry 9 is located on the left side of the
4 in the upper space.

The support rail 8 on the right side of the process stand 9 in the figure.
2B is disposed near the lower part of the lowermost developing unit 4K. The support rail 82B is provided with the developing means 4Y, 4M, 4
C and 4K are arranged at positions where they do not hinder the operation of attaching and detaching C and 4K to and from the process base 9.

In FIG. 8, a gantry selection release mechanism 40 is attached to the rear of the main unit, and the pull-out operation of either the process gantry 8 or the transport gantry 9 is fixed based on the operation of the lock lever 91. Alternatively, the pull-out operation of both the process gantry 8 and the transfer gantry 9 is fixed. This is to prevent the process platform 8 and the transport platform 9 from falling due to being pulled out at the same time, or to prevent the both components from contacting and breaking when the process platform 8 and the transport platform 9 are pulled out at the same time.

The gantry selection release mechanism 40 is provided between the inner surface of the rear housing inside the main unit and the back surfaces of the process gantry 8 and the transport gantry 9. The gantry selection release mechanism 40 has a metal connecting rod 41 reaching the above-described lock lever 91, and a rectangular metal operating piece (panel) 42 fixed to the other end of the connecting rod 41.

The operation piece 42 is formed by punching an iron plate having a thickness of about 3 mm to 4 mm into a predetermined shape. The connecting rod 41 and the operation piece 42 are firmly melt-bonded by electric or gas welding or the like. For example, a pilot hole or a through-hole may be provided in advance on the operation piece 42, and the connecting rod 41 may be welded after abutting or passing through the hole. The connecting rod 41 has a predetermined diameter (outer diameter). As the connecting rod 41, an iron rod having a diameter of about 5 mm to 10 mm is used. This is for transmitting the rotational operation force of the lock lever 91 to the rear without twisting.

In addition, the gantry selection release mechanism 40 includes an L-shaped lock assisting member 43, an urging member 44, and a stepped projection member 4 having a large diameter portion 45A and a small diameter portion 45B shown in FIG.
5 and a semi-circular sickle-shaped lock saddle member 46.

The lock saddle member 46 is fixed to the inner surface of the rear housing inside the main body device by, for example, a screw. This is for firmly holding the process gantry 8 and / or the transport gantry 9. The lock saddle member 46 has a thickness of 3 mm to 4 m.
An iron plate of about m is punched into a predetermined shape, and then formed by bending into a saddle shape. The lock saddle member 46 is used by engaging a metal L-shaped lock auxiliary member 43.

An opening 43A with a clearance groove is provided at one end in the longitudinal direction of the lock assisting member 43. The width of the relief groove 43B is substantially equal to the outer diameter of the small diameter portion 45B of the projection member 45. The opening 43A is a large diameter portion 45A of the projection member 45.
Is slightly larger than the outside diameter.

This is because the protruding member 45 is formed with respect to the opening 43A.
Through the escape groove 43B.
This is to prevent the protrusion member 45 from coming off. The lock assisting member 43 is formed by forming an opening 43A and a relief groove 43B in an iron plate having a thickness of about 3 mm to 4 mm, and bending this iron plate into an L shape. Of course, the opening 43A and the relief groove 43B may be formed after bending into an L-shape.

The urging member 4 is provided at one end of the lock assisting member 43.
4 is attached, and one end of the urging member 44 is attached to a protrusion 58 or the like on the inner surface of the housing. Lock auxiliary member 43
This is for always biasing in a certain direction. Urging member 44
A spring is used. In addition, the urging member 4
4 may be a toggle spring, a leaf spring, or the like.

The projecting member 45 is firmly attached to the back of the process base 8, and the opening 4
3A, and is fixed by the escape groove 43B. For example, the protrusion member 45 is provided with a clearance groove 43B due to the longitudinal displacement of the lock assisting member 43 due to the urging force of the urging member 44.
To be engaged. The projecting member 45 is the escape groove 4
3B, the lock auxiliary member 43 is brought into contact with the lock saddle member 46, so that the protrusion member 45 is engaged.
Is mounted in a locked state.

The operating piece 42 at the tip of the connecting rod from the carrier base 9 is engaged with the lock saddle member 46. The operation piece 42 changes the position of the L-shaped lock assist member 43 according to the operation position of the lock lever 91 described above. For example, when a rotational force that overcomes the urging force of the urging member 44 is applied, the operation piece 42 pulls down the lock auxiliary member 43 and the projecting member 45 of the process base 8 is moved to the opening 43.
A is set at a position that matches A. As a result, the projecting member 45 comes into a state of freely falling out of the opening 43A, so that the process gantry 8 can be pulled out to the outside.

Further, when the operating piece 42 is located at the sickle-shaped portion of the lock saddle member 46 according to the operating position of the lock lever 91, the operating piece 42 does not come off. Thereby, the transport base 9 can be locked. When the operation piece 42 comes to a position crossing the sickle-shaped portion of the lock saddle member 46 according to the operation position of the lock lever 91,
The operation piece 42 comes off. As a result, the transport gantry 9 can be pulled out.

Next, a description will be given of the lock mechanism 50 of the operation piece 42 when the transfer platform is pulled out. FIGS. 10A and 10B are cross-sectional views illustrating a configuration example of the lock mechanism 50 of the operation piece 42. In this example, a stopper 57 is provided on a rail or the like of the transfer frame 9.
Is assumed to be provided.

The lock mechanism 50 shown in FIG. 10A is attached to the back of the transfer stand 9. The lock mechanism 50 includes a U-shaped lock member 51, an urging member 52, and a spring holding portion 5.
Three. A through-hole 54 is provided on the rear surface of the transfer frame 9 shown in FIG. 10A through which the connecting rod 41 reaching the operation piece 42 is provided. Parts 55 and 56 are provided.

The lock member 51 has two legs 51A and 51B having different lengths, and is made of a metal member or a hard resin member. The leg 51A of the lock member 51 is engaged with the opening 55 of the transport gantry 9 from the inside toward the outside, and similarly, the leg 51B of the lock member 51 is engaged with the opening 56 from the inside to the outside. Are engaged and can be freely moved.

The longer leg 51A has a length such that it comes into contact with the inner surface of the housing in the main unit when the transport gantry is stored. The shorter leg 51B is defined to have a length that covers the operation piece 42 joined to the connecting rod 41 when the shorter leg 51B is engaged with the opening 56 and comes out entirely.

The two openings 55 and 56 of the transfer base 9
A spring holding portion 53 is provided inside the upper side of the lock member 51. The urging member 52 is inserted between the spring holding portion 53 and the lock member 51 so as not to fall off. This is because the lock member 51 is always urged from the inside to the outside. A spring is used for the urging member 52. In addition, a toggle spring, a leaf spring, or the like may be used for the biasing member 52.

According to such a lock mechanism 50, FIG.
0A, when the longer leg 51A is not in contact with the inner surface of the housing in the main body device, that is, when the transport gantry 9 is pulled out, the urging member 52 moves the lock member 51 from inside to outside. , The lock member 51 is pressed against the outside by the openings 55 and 56, and the shorter leg 51B covers the operation piece 42 joined to the connecting rod 41. Is made. Therefore, the rotational movement of the operation piece 42 can be prevented, and the lock lever 91 can be restrained.

Conversely, the longer leg 5 shown in FIG.
When the transport frame 9 is in contact with the stopper 57 while the transport frame 9 is in contact with the inner surface of the housing in the main body device, that is, when the transport platform 9 is loaded into the main body device, the biasing member 52
, And the lock member 51 is moved inward. By this movement, the locking member 51
Are retracted inward at the openings 55 and 56, and the shorter leg 51B is removed from the operation piece 42. Therefore, the rotational movement of the operation piece 42 can be made free, and the restraint of the lock lever 91 can be released.

FIG. 11 shows the operation piece 42, the lock auxiliary member 43, and the lock saddle member 4 in the gantry selection release mechanism 40.
It is a front view which shows the example of a dimension of No. 6. In FIG. 11, the height of the lock assisting member 43 in the longitudinal direction is H, the diameter of the semicircular portion of the lock saddle member 46 is D, and the operating piece 42
Is the length of L ′, the rotation axis p0 of the operation piece 42 is on the opposite side of the engagement position of the lock assisting member 43 (left side on the paper).
The gantry selection release mechanism 40 can be made compact by reducing the proportion of each member.

That is, the diameter D of the lock saddle member 46,
Both the length L 'of the operation piece 42 and the height H of the lock assisting member 43 can be shortened. Thereby, the space between the rear inner surface of the housing inside the main body device and the back surfaces of the process mount 8 and the transfer mount 9 and the mount selection releasing mechanism 40 having a size corresponding to the space in the lateral direction can be provided.

Next, an operation example of the image forming apparatus 200 will be described. 12 to 14 show the image processing apparatus 200.
Of operation at the time of operating the lock lever 91 in (1)
It is the front view and sectional view near the stand selection release mechanism which shows 3). Reference is also made to FIGS.

In this example, a gantry selection release mechanism 40 of a type in which the rotation axis p0 of the operation piece 42 is shifted to the left is prepared, and both the process gantry 8 and the transport gantry 9 are housed in the apparatus main body. Is assumed. That is, the projecting member 45 of the process gantry 8 is in a state of being engaged with the relief groove 43B.

At the time of storing the process & transport gantry At the time of storing the process & transport gantry, the lock lever 91 shown in FIG. 4A is in the upright position. In this case, the operation piece 42 shown in FIG. 12A is located at the sickle-shaped portion of the lock saddle member 46. Accordingly, the operation piece 42 is caught by the sickle-shaped portion and does not come off. Thereby, the transport base 9 can be locked.

In this state, the operating piece 42 does not act on the L-shaped lock auxiliary member 43 at all. On the other hand, the projecting member 45 of the process gantry 8 causes the escape groove portion 43B to be displaced by the longitudinal displacement of the lock assisting member 43 due to the urging force of the urging member 44.
It is in a state of engaging with. When the lock assisting member 43 is in contact with the lock saddle member 46 in a state of being engaged with the clearance groove portion 43B, the projecting member 45
The process stand 8 with the lock saddle member 4
6 is locked. Therefore, both the process platform 8 and the transport platform 9 shown in FIG. 12B can be locked at the same time.

At the time of selecting and opening the process frame When the process frame is selected and opened, the lock lever 91 shown in FIG. 4B is at the right position. In this case, FIG.
The operation piece 42 shown in FIG. 2A is rotated clockwise (rightward) by 90 ° from the sickle-shaped portion of the lock saddle member 46 and moved to the position shown in FIG. 13A.

At this time, the operating piece 42 pulls down the lock assisting member 43 due to the application of a rotational force that overcomes the urging force of the urging member 44, and fits the projecting member 45 of the process base 8 into the opening 43A. Made in position. Therefore, the projection member 45 is freely released from the opening 43A, so that the process base 8 can be pulled out to the front side (outside).

Further, in this state, the operation piece 42 is hooked below the sickle-shaped portion of the lock saddle member 46 so as not to come off. Therefore, the process platform 8 shown in FIG. 13B can be pulled out, but the transport platform 9 is still in the locked state.

At the time of selecting and opening the transfer platform, the selection and release of the transfer platform is a case where the lock lever 91 shown in FIG. 4C is at the left position. In this case, FIG.
14 is rotated counterclockwise (left side) by 90 ° from the sickle-shaped portion of the lock saddle member 46 and moved to the position shown in FIG. 14A. Therefore, since the operation piece 42 comes out freely below the sickle-shaped portion of the lock saddle member 46, the transport gantry 9 can be pulled out to the front side (outside).

At this time, the operating piece 42 does not act on the lock assisting member 43 at all. On the other hand, the projection lock assisting member 43 is a lock assisting member 43 by the urging force of the urging member 44.
Is in a state of being engaged with the escape groove portion 43B due to the displacement in the longitudinal direction. Therefore, the process base 8 shown in FIG.
Lock state can be continued.

As described above, according to the color image forming apparatus 200 according to the second embodiment of the present invention, the space between the inner surface of the rear housing inside the main unit and the rear surfaces of the process stand 8 and the transfer stand 9 is provided. A gantry selection release mechanism 40 is provided, and one of the process gantry 8 and the transport gantry 9 is selected by operating the lock lever 91.

Therefore, the process frame 8 and the transfer frame 9 can be prevented from being pulled out at the same time, so that the apparatus body A can be prevented from overturning due to the weight balance collapse, and the process frame 8 and the transfer frame 9 can be pulled out simultaneously. In this state, it is possible to prevent both parts from contacting each other and being damaged.

(3) Third Embodiment FIG. 15 is a perspective view showing a configuration example of a gantry individual release mechanism 60 of a color image forming apparatus 300 according to a third embodiment of the present invention. In this embodiment, a gantry individual release mechanism 60 as another example of the gantry release mechanism is provided, and a solenoid (electromagnet) 6 is attached to the process gantry 8 and the transport gantry 9.
1. An urging member 62 and an L-shaped lock assisting member 63 are individually prepared, and these lock assisting members 63 are
1 and the biasing member 62 are individually controlled. The components having the same reference numerals and names as those in the second embodiment have the same functions, and the description thereof will be omitted. The other configuration of the color image forming apparatus 300 is the same as that of the first color image forming apparatus 100, and a description thereof will be omitted.

As the L-shaped lock assisting member 63, a lock assisting member 43 having no escape groove 43B is used. The opening 63A of the lock assisting member 63 is formed slightly larger than the large diameter portion 45A of the projection member 45. This is so that the stepped projection member 45 previously attached to the transfer frame 9 or the process frame 8 can freely pass through.

A solenoid 61 is joined below the L-shaped lock assisting member 63, and an urging member 6 is arranged above the solenoid 61.
2 is attached. A spring is used for the urging member 62. In addition, a toggle spring, a leaf spring, or the like may be used.

Of course, the other end of the urging member 62 is engaged with the projection 58 or the like on the inner surface of the housing in the main body device.
The lock auxiliary member 63 is pulled up. Therefore, the large diameter portion 45A of the projection member 45 is
Is caught on the edge of the opening 63A and cannot be removed. Thereby, it is possible to prevent the transfer gantry 9 and the process gantry 8 from moving to the front side (lock function).

The stroke amount (displacement amount) of the solenoid 61B joined below the lock assisting member 63 is predetermined, and the lock assisting member 63 is pulled downward by turning on the power of the solenoid 61. At this time, based on the stroke amount, the opening 63A and the outer diameter portion 45A of the stepped projection member 45 are fitted to a position where they match. Therefore, the opening 63A of the lock assisting member 63
, So that the stepped projection member 45 can pass freely. As a result, the transfer frame 9 and the process frame 8 can be pulled out to the front side (unlock function).

Next, detection means for controlling the above-described solenoid 61 will be described. 16A and 16B are cross-sectional views illustrating a configuration example of the gantry sensor mechanism 31. A gantry sensor mechanism 31, which is an example of a first detection unit, is attached to the rear surface of the transport gantry 9 shown in FIG. Is made.

The gantry sensor mechanism 31 includes a photo sensor 33,
It has a movable member 34 with a bar-shaped flange, a biasing member 35 and a sensor mounting portion 36. The photo sensor 33 has a light emitting element and a light receiving element. An opening 37 is provided on the rear surface of the transfer gantry 9 shown in FIG. 16A, and a movable member 34 is inserted into the opening 37 and movably engaged therewith.

An urging member 35 is provided between the rear surface of the transfer frame 9 and the collar 34A for preventing the movable member 34 from falling off.
Is attached and is always urged to pull the movable member 34 from the inside to the outside. Urging member 35
A spring is used. In addition, the urging member 3
A toggle spring, a leaf spring, or the like may be used for 5.

The movable member 34 has a length such that one end of the movable member 34 comes into contact with the inner surface of the housing in the apparatus main body when the transport gantry is stored. At the other end, a light-shielding portion 34B is provided, which is inserted between the light-emitting element and the light-receiving element when the carrier is stored, so as to block the optical path. The sensor mounting part 3 is provided at the bottom of the transport base 9.
6 are provided, and the photo sensor 33 is attached.

When the movable member 34 contacts the inner surface of the housing, the photosensor 33 blocks the optical path by the light shielding portion 34B, and when the movable member 34 is separated from the inner surface of the housing, the light shielding portion 34B is moved from the optical path. The mounting position is adjusted so that it comes out.

According to such a gantry sensor mechanism (hereinafter referred to as a transport gantry sensor) 31, on the premise that the stopper 38 is provided on a rail or the like of the transport gantry 9, FIG.
In a state where the transfer frame 9 is in contact with the stopper portion shown in FIG. 6A and the movable member 34 is in contact with the inner surface of the housing, for example, the photo sensor 33 is turned off. At this time, the light shielding portion 34B is inserted between the light emitting element and the light receiving element, so as to block the optical path. Therefore, it is possible to detect the storage of the transport gantry by the gantry detection signal S1 (photosensor output, for example, “0”) obtained from the photosensor 33.

Further, the transfer stand 9 is separated from the stopper 38 shown in FIG.
The photo sensor 33 is turned on in a state where is separated from the inner surface of the housing. At this time, the light shielding portion 34B escapes from between the light emitting element and the light receiving element, and does not block the optical path. Therefore, it is possible to detect the drawer of the transport gantry by the gantry detection signal S1 (the photosensor output is, for example, “1”). In addition,
The process gantry 8 is also provided with a gantry sensor mechanism (hereinafter, referred to as a process gantry sensor) 32 as an example of a second detection unit, but the description thereof will be omitted.

Next, the control system of the individual gantry release mechanism 60 will be described. FIG. 17 is a block diagram illustrating a configuration example of a control system of the gantry individual release mechanism 60. The control system of the individual gantry release mechanism 60 shown in FIG. 17 is provided with a control device 15 to control the individual gantry release mechanism 60 based on the gantry detection signals S1 and S2 from the transport gantry sensor 31 and the process gantry sensor 32. Is made.

The control unit 15 includes a transport gantry sensor 31, a process gantry sensor 32, a transport gantry release button (switch) 12, a process gantry release button 13, and a display unit 1.
4. Solenoid # 1 for the transfer gantry and solenoid # 2 for the process gantry are connected. Transfer stand sensor 31
Then, the gantry detection signal S1 is detected and output to the control device 15.

The process gantry sensor 32 detects the gantry detection signal S2 and outputs it to the control device 15. The transport gantry release button 12 is operated by an operator when releasing the transport gantry 9. The process gantry release button 13 is operated by an operator when releasing the process gantry 8.

The display means 14 displays a message such as "Please attach the transfer stand" or an error message. In the case of the solenoid # 1 for the transport platform, the transport platform release button 12
It is turned on and off based on the gantry detection signal S1. The process gantry solenoid # 2 is turned on / off based on the process gantry release button 13 and the gantry detection signal S2.

Next, an operation example of the image forming apparatus 300 will be described. FIG. 18 and FIG.
7 is a flowchart illustrating an operation example (Nos. 1 and 2) at 0. In this example, the gantry individual release mechanism 60 described in FIG. 15 is prepared, and the process gantry 8 and the transport gantry 9 are provided.
Are assumed to be stored in the apparatus body. That is, the projecting members 45 of the process gantry 8 and the transport gantry 9 are engaged (hooked) with the opening 63A of the lock assisting member 63. The case where the process gantry and transfer gantry release buttons 12 and 13 can be selected is taken as an example. Based on this, the control branches in step A1 of the flowchart shown in FIG. 18 in accordance with the selection of the release button of the transport gantry 9 or the process gantry 8.

[When the process gantry release button is selected] When the process gantry release button 13 is depressed in this step A1, the switch is turned on, so that the process proceeds to step A2 and the transport gantry 9 is loaded into the apparatus main body. Is checked by the control device 15. The check at this time is determined by the signal logic of the transport gantry sensor 31. For example, it is possible to identify a state in which the transport gantry 9 is not loaded in the apparatus main body by the gantry detection signal S1 = "1".

Therefore, if the transport gantry 9 is not actually loaded in the apparatus main body, the process proceeds to step A3, and the message "Please load the transport gantry." Is displayed on the display means 14. Thereafter, the process returns to step A1, and when the process gantry release button 13 is pressed again, the switch is turned on.

Then, in step A2, it is assumed that the transport gantry 9 has been loaded, and the flow proceeds to step A4.
In step A4, the control device 15 determines whether the solenoid # 1 for the transfer gantry is turned off. If the solenoid # 1 has not been turned off, the process proceeds to step A5, and the solenoid # 1 is turned off. Then, the process returns to step A2. This time, since the power supply of the solenoid # 1 is turned off, it is determined in step A4 that the solenoid # 1 is off, and the process proceeds to step A6.

In step A6, the transport gantry release button 12
Is turned off by the control device 15. When the transfer frame release button 12 is turned on,
Since both release buttons 12 and 13 have been pressed,
The process proceeds to step A7 to execute error processing. In this process, "the transport frame and the process frame release button are both pressed" is displayed on the display means. Therefore,
The process gantry release control is stopped here.

If the carrier gantry release button 12 is turned off in step A6, the solenoid # 2 is turned off in step A8.
Turn on. At this time, the lock assisting member 6 shown in FIG.
By turning on the power supply of the solenoid (# 2) 62 below the lock member 3, the lock auxiliary member 63 is pulled downward so as to overcome the urging force of the urging member 35.

For example, based on a predetermined stroke amount, the opening 63A and the outer diameter portion 45A of the stepped projection member 45 are fitted to a position where they match. Accordingly, the stepped projection member 45 can freely pass through the opening 63A of the lock assisting member 63. As a result, the process gantry 8 can be pulled out to the front side while the transport gantry 9 is locked.

[When the transport gantry release button is selected] When the transport gantry release button 12 is pressed in step A1 of the flowchart shown in FIG. 18, the switch is turned on.
In step A9 of the flowchart shown in FIG. 19, the control device 15 checks whether the process base 8 is loaded in the apparatus main body. The check at this time is determined by the signal logic of the process mount sensor 32. In this case, the state where the process gantry 8 is not loaded in the apparatus main body can be identified by the gantry detection signal S2 = "1".

Therefore, if the process gantry 8 is not loaded in the apparatus main body, the flow shifts to step A10, and the message "Please load the process gantry" is displayed on the display means 14. Thereafter, the flow returns to step A1 in the flowchart shown in FIG.
When 2 is pressed again, the switch turns on.

Then, in step A9, the process base 8
Is determined to be loaded, and the flow shifts to step A11. In step A11, the control device 15 determines whether the solenoid # 2 for the process stand is turned off. If the solenoid # 2 has not been turned off, the process proceeds to step A12, and the solenoid # 2 is turned off. Thereafter, the process returns to step A9. This time solenoid #
Since the power supply of No. 2 is turned off, it is determined in step A11 that the solenoid # 2 is turned off, and the process proceeds to step A13.

In step A13, the control device 15 determines whether the process gantry release button 13 is turned off. When the process gantry release button 13 is turned on, since both release buttons 12 and 13 are pressed down, the process shifts to step A14 to execute error processing. In this process, the display means 14 displays "both the transfer frame and the process frame release button have been pressed". Therefore, the transfer gantry release control is stopped here.

If the process gantry release button 13 is turned off in step A13, the solenoid # 1 is turned on in step A15. At this time, when the power of the solenoid 62 (# 1) below the lock assisting member 63 shown in FIG. 9 is turned on, the lock assisting member 63 is pulled downward so as to overcome the urging force of the urging member 35. For example, based on a predetermined stroke amount, the opening 63A is fitted to a position where the outer diameter portion 45A of the stepped projection member 45 matches.

Therefore, the opening 63 of the lock assisting member 63
A allows the stepped projection member 45 to freely pass through. Thus, the transport gantry 9 can be pulled out to the front side while the process gantry 8 is locked. After that, the process shifts to step A16 to determine whether or not to terminate the individual gantry processing. If the gantry individual release process is to be continued, the process returns to step A1. The process is completed by loading the transfer frame 9 and the process frame 8.

As described above, according to the color image forming apparatus according to the third embodiment of the present invention, the gantry is provided between the inner surface of the rear housing inside the main unit and the back of the process gantry 8 and the transport gantry 9. An individual release mechanism 60 is provided, and one of the process platform 8 and the transport platform 9 is selected by operating the process platform and transport platform release buttons 12 and 13.

Therefore, as in the second embodiment, the state in which the process platform 8 and the transport platform 9 are pulled out at the same time can be eliminated. It is possible to prevent the two parts from contacting each other and being damaged in a state in which the and the transfer base 9 are pulled out at the same time.

In each of the above-described embodiments, the color image forming apparatus having the endless belt-shaped intermediate transfer body 70 without the seam for the process stand 8 has been described. However, the present invention is not limited to this. The present invention is also applicable to a color image forming apparatus having an endless belt-shaped intermediate transfer member having a seam.

Further, a plurality of image forming units are arranged in the conveying direction, and the toner images of different colors formed on the photosensitive drums of the image forming units are sequentially transferred onto a sheet held on a conveying belt. The present invention is also applicable to a color image forming apparatus of a system.

Further, in the color image forming apparatus of the present invention, the light emitting element (LE) is used as the exposure means 3Y, 3M, 3C, 3K.
D) An array may be used, and the light emitting element array is arranged at a predetermined position in the process base 8.

Further, the present invention is not limited to the above embodiment, but includes an image carrier (including an electrostatic recording medium), an intermediate transfer member, a plurality of developing means (wet developing means, ion flow control, etc.). And other color image forming apparatuses. Of course, the present invention can be applied to a monochrome image forming apparatus.

[0123]

As described above, the first embodiment according to the present invention is described.
According to the image forming apparatus, the image carrier and the transfer unit are provided with a transport gantry for transporting and passing the recording paper in chronological order, and the transport gantry has a portion from the paper feed port of the transport gantry to the transfer position. It is longer than the maximum length of recording paper handled by the apparatus, and has a structure that can be pulled out from the inside of the apparatus main body to a predetermined external position.

According to this configuration, most of the paper feed conveyance path where the recording paper is expected to be jammed can be taken out of the main unit, so that the recording paper can be transferred to the transfer means from the paper feed port to the paper discharge port of the transport base. The paper jam processing related to the recording paper can be smoothly performed in a state where the transport gantry is pulled out from the inside of the apparatus main body to a predetermined external position, such as the arrival state and the arrival state of the recording sheet to the fixing unit.

According to the second image forming apparatus of the present invention, there is provided a gantry releasing mechanism for fixing the pull-out operation of the transport gantry or the process gantry based on the operation of selecting one of the process gantry and the transport gantry. Things.

With this configuration, either the process gantry or the transport gantry can be pulled out, so that the process gantry and the transport gantry are not simultaneously pulled out. Therefore, either one of the process stand or the transfer stand remains in the apparatus main body, so that it is possible to prevent the apparatus main body from falling over due to the weight balance collapse, and
Since the situation where the process gantry and the transport gantry are pulled out at the same time is eliminated, it is also possible to prevent both parts from being contacted and damaged.

The present invention relates to an image forming apparatus using an electrophotographic method, such as a copying machine, a printer, a facsimile, etc., and more particularly, to a plurality of image carriers, latent image forming means, and developing means.
It is very suitable for application to a tandem type color image forming apparatus for transferring toner images formed on a plurality of image carriers to an intermediate transfer member.

[Brief description of the drawings]

FIG. 1 is a schematic cross-sectional view illustrating a configuration example of an image forming apparatus 100 according to a first embodiment of the invention.

FIG. 2 is a cross-sectional view illustrating a configuration example of a process base 8;

FIG. 3 is a perspective view showing a configuration example of a transport gantry 9 at the time of drawing.

4A to 4C are front views showing examples of handling the lock lever 91. FIG.

FIG. 5 is a conceptual diagram showing an example of the internal configuration of a transport base 9;

FIG. 6 shows a path release mechanism 911, 91 in the transport base 9;
FIG. 2 is a conceptual diagram illustrating a configuration example of FIG.

FIG. 7 is a perspective view showing a configuration example of a color image forming apparatus 200 according to a second embodiment of the present invention when the process frame 8 is pulled out.

FIG. 8 is a side view of a partly crushed color image forming apparatus 200 showing an example of an attachment position of the gantry selection release mechanism 40.

FIG. 9 is a perspective view showing an example of assembling the gantry selection releasing mechanism 40.

FIGS. 10A and 10B are cross-sectional views illustrating a configuration example of a lock mechanism 50 of the operation piece 42. FIGS.

11 is a front view showing an example of dimensions of each member in the gantry selection release mechanism 40. FIG.

12A and 12B are a front view and a cross-sectional view showing an operation example (No. 1) when the lock lever is operated in the gantry selection release mechanism 40.

13A and 13B are a front view and a cross-sectional view illustrating an operation example (part 2) of the gantry selection release mechanism 40 when the lock lever is operated.

14A and 14B are a front view and a cross-sectional view illustrating an operation example (part 3) of operating the lock lever 91 in the gantry selection release mechanism 40.

FIG. 15 is a perspective view illustrating a configuration example of a gantry individual release mechanism 60 of a color image forming apparatus 300 according to a third embodiment of the invention.

FIGS. 16A and 16B are cross-sectional views illustrating a configuration example of a gantry sensor mechanism 31. FIGS.

FIG. 17 is a block diagram showing a configuration example of a control system of a gantry individual release mechanism 60;

FIG. 18 is a flowchart illustrating an operation example (part 1) of the image processing apparatus 300.

FIG. 19 is a flowchart illustrating an operation example (part 2) of the image processing apparatus 300.

[Explanation of symbols]

1Y, 1M, 1C, 1K Image carrier 4Y, 4M, 4C, 4K Developing means 5Y, 5M, 5C, 5K Primary transfer means 5A Secondary transfer means A Main body 8 Process gantry 9 Transport gantry 14 Display means 15 Control unit 21 Image forming process unit 24 Fixing device 31 Mount sensor mechanism (transfer mount sensor; first detecting means) 32 Process mount sensor (second detecting means) 40 Mount selection release mechanism 50 Lock mechanism 60 Individual mount release mechanism 70 Intermediate transfer member 92 gantry body 100 image forming apparatus

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) G03G 15/16 103 G03G 15/16 103 3F100 21/16 15/00 554 3F102 (72) Inventor Susumu Tashiro Tokyo 2970, Ishikawa-cho, Hachioji-shi, Tokyo Konica Corporation (72) Inventor Masahiro Shigetomi 2970, Ishikawa-cho, Hachioji-shi, Tokyo Konica Corporation F-term (reference) 2H028 BA06 BA09 BA16 2H071 AA18 BA03 BA04 BA14 BA17 BA19 BA27 DA06 DA08 DA09 DA13 DA23 EA06 EA18 2H072 CA01 CB01 CB03 CB08 EA17 EA18 HB07 2H200 FA19 GA02 GA12 GA23 GA34 GA44 GA47 GB12 GB22 HB12 HB22 JA02 JB10 JB13 JB20 JC04 JC07 3F049 AA04 CA31 DA03 3 AB01 BA02 BA09 BB02 DA08 EA03 FA08

Claims (12)

[Claims] An image carrier that forms an electrostatic latent image; a developing unit that visualizes the electrostatic latent image on the image carrier with a developer to form a toner image; Transfer means for transferring the toner image on the image bearing member visualized by the recording medium to the recording paper; fixing means for fixing the toner image on the recording paper transferred by the transfer means; and transporting the recording paper to the transfer means A transfer platform having a paper feed port for passing paper, wherein the transport frame has a portion extending from a paper feed port of the transport frame to a transfer position, which is larger than a maximum length of recording paper handled by the apparatus. An image forming apparatus which is long and has a structure capable of being pulled out from the inside of the apparatus main body to a predetermined external position. 2. An apparatus main body, an image carrier for forming an electrostatic latent image, a developing unit for developing the electrostatic latent image on the image carrier with a developer to form a toner image, and the developing unit Transfer means for transferring the toner image on the image bearing member visualized by the recording medium to the recording paper, fixing means for fixing the toner image on the recording paper transferred by the transfer means, and transporting the recording paper to the transfer means A transfer platform having a paper feed port for passing paper, the transport frame has a paper feed port and a paper discharge port, and temporarily stops the recording paper taken in from the paper feed port, and at a predetermined timing. A conveyance roller for feeding the recording paper by the transfer means, a manual paper feed path for feeding the recording paper stored in a manual tray to the transfer means, and a recording paper stored in a paper cassette. Cassette supply for feeding to the transfer means A paper path, a paper discharge path through which the recording paper on which the toner image is fixed passes through the paper discharge port to discharge the recording paper to the outside of the apparatus main body, and a recording paper fed by the transport roller. An image forming apparatus comprising: a transfer unit and a transfer roller for pressing a toner image. 3. A case in which a paper feed path for a cassette is provided in the transport gantry, wherein the length from the leading end of the paper feed path for the cassette to the registration roller is M, and the recording capable of forming an image is performed. 3. The image forming apparatus according to claim 1, wherein, when a maximum length of the paper is N, a relationship of M ≧ N is satisfied. 4. 4. When the length from the tip of the manual paper feed path of the transport stand to the registration roller is L, and the maximum length of the recording paper on which an image can be formed is N, L ≧ N. The image forming apparatus according to claim 1, wherein a relationship is established. 5. The conveyance pedestal has a reversing paper feed path for reversing the recording paper having an image formed on one side thereof and feeding the recording paper to the transfer unit again. The image forming apparatus according to claim 1, wherein: 6. A transport roller for temporarily stopping the recording paper inverted by the reverse paper feed path, which is located upstream of a junction of the manual paper feed path and the cassette paper feed path of the transport gantry. When the length from the transport roller to the tip of the reverse paper feed path is X, and the maximum length of the recording paper on which an image can be formed is N, the relationship of X ≧ N is established. The image forming apparatus according to claim 5, wherein: 7. A path release mechanism is provided in a manual paper feed path, a cassette paper feed path, a paper discharge path, and / or a reverse paper feed path of the transport gantry.
3. The image forming apparatus according to claim 1, wherein 8. An apparatus main body, a plurality of image carriers for forming an electrostatic latent image, and developing means for visualizing the electrostatic latent image with a developer to form a toner image. A process stand that can be pulled out, a transfer unit that transfers the toner image on the image carrier visualized by the developing unit to a recording sheet, and a fixing unit that fixes the toner image on the recording sheet transferred by the transfer unit And a transfer platform that transports and passes the recording paper to the transfer unit and the fixing unit, and fixes the pull-out operation of the transfer frame or the process frame based on a pull-out selection operation of any one of the process frame and the transfer frame. An image forming apparatus, comprising: 9. A detection means for detecting a withdrawal operation of the transfer gantry, a second detection means for detecting a withdrawal operation of the process gantry, and a detection signal from the first and second detection means. The image forming apparatus according to claim 8, further comprising: a controller that controls the gantry release mechanism based on the controller. 10. The image forming apparatus according to claim 8, wherein an intermediate transfer member for sequentially transferring toner images formed on the plurality of image carriers is provided on the process gantry. 11. The conveyance pedestal has a reversing paper feed path for reversing the recording paper having an image formed on one side thereof and feeding the recording paper to the transfer unit again. The image forming apparatus according to claim 8, wherein 12. The image forming apparatus according to claim 8, wherein the process gantry and the transport gantry are drawn out to the front side of the apparatus main body.