JPH04179979A - Structure of transfer drum - Google Patents

Abstract

PURPOSE:To facilitate handling of jam by fixing the front ends of a pair of guiding plates facing each other at a prescribed interval on the front side plate, and their rear ends on the back side plate, to form the guiding path of a transfer material, and forming a slit cut from an end edge part on a part corresponding to the guiding path side surface of the back side plate. CONSTITUTION:A guiding member for leading the transfer material P to the prescribed position of a transfer drum main body 11 is arranged between the front side plate 1a and the back side plate 1b, and the front ends and rear ends of a pair of the guiding plates 13c and 13d facing each other at the prescribed interval are fixed on the front side plate 1a, and on the back side plate 1b, respectively, to form the guiding path 13. On the other hand, the slit cut from the end edge part is formed on the part corresponding to the side surface of the guiding path 13 of the back side plate 1b. Therefore, when the transfer material P is jammed in the guiding path 13, and the transfer drum 1 is moved forward in the shaft direction of the drum from a device main body A1 and pulled out, since the transfer material P passes the slit, the transfer drum 1 is pulled out forward in the shaft direction of the drum without catching the transfer material P on the back side plate 1b. Thus, the jam processing is easily carried out.

Description

[Detailed Description of the Invention] <Industrial Application Field> The present invention is forged into an image forming apparatus, etc., and holds a transfer material when transferring a toner image formed on a photoreceptor drum to the transfer material. Regarding the transfer drum.

<Prior Art> Full-color image forming apparatuses having a transfer drum have been known so far (see, for example, Japanese Patent Laid-Open No. 113481/1981). In this type of full-color image forming apparatus, plain paper, OHP sheet, etc. are used as transfer materials on the circumference of the transfer drum.
The transfer process involves wrapping and holding label paper, postcards, etc., bringing the transfer drum wrapped around the transfer material into contact with the photoreceptor drum, rotating it synchronously, and transferring the toner image formed on the photoreceptor drum onto the transfer material. It will be done.

The transfer material is supplied to a predetermined position of the transfer drum at a predetermined timing via a paper guide path, and its leading end is gripped by a clip disposed on the surface of the transfer drum, and is wound and held around the transfer drum.

If the timing at which the leading edge of the transfer material is applied to the clip and the timing at which it is gripped are even slightly off, the leading edge of the transfer material will not be clipped and gripped, resulting in a paper jam.

In order to facilitate the handling of paper jams, the transfer drum is often made removable from the main body of the apparatus.

As shown in FIG. 11, this kind of transfer drum with a removable structure has a cylindrical transfer drum main body 81 whose front and rear ends are attached to a front side plate 82 and a rear side plate 83, and the transfer drum main body 81 is rotatable. is supported by Further, the transfer drum main body 81, the front side plate 82, and the rear side plate 83 are made slidable in the drum axis direction of the transfer drum main body 81 by a sliding member 86 attached to the front side plate 82, the rear side plate 83, and the apparatus main body, The transfer drum 80 can be pulled out from the main body of the apparatus.

Note that between the front side plate 82 and the rear side plate 83, there is a guide path 84 for guiding the paper sent out from the pre-transfer roller 85, which takes the timing of supplying the paper to the transfer drum 80, to a predetermined position on the transfer drum main body 81. is provided.

<Problem to be Solved by the Invention> In the transfer drum 80 having the above configuration, if a jam occurs mainly due to a clipping error at the leading edge of the paper, the first
As shown in FIG. 2, the leading end of the paper 8p is stopped in the guide path 84. In this state, when the transfer drum 80 is pulled forward in the axial direction of the drum to remove the paper 8P, the leading edge of the jammed paper 8P gets caught on the rear plate 82, which may cause the paper 8P to tear or the transfer drum to remove the paper 8P. 80
There was a problem in that the jam could not be pulled out, making it even more difficult to clear the jam.

The present invention has been made to solve the above-mentioned problems, and an object of the present invention is to provide an image forming apparatus that can easily handle paper jams.

<Means for Solving the Problems> In order to solve the above problems, the structure of the transfer drum according to the first invention includes a cylindrical transfer drum body, which is attached to the front end of the transfer drum body, and which allows the transfer drum to rotate freely. A supporting front side plate, a rear side plate attached to the rear end of the transfer drum body and rotatably supporting the transfer drum, and a moving means for moving the transfer drum body, front side plate, and rear side plate in the drum axis direction of the transfer drum body. The structure of the transfer drum is such that a transfer material on which an image is transferred during image transfer is held by being wrapped around the surface of the transfer drum main body, and the transfer material is held between the front side plate and the rear side plate. A guide member is arranged to guide the body to a predetermined position.
The guide member includes a pair of guide plates facing each other at a predetermined interval, the front end of each guide plate is fixed to the front side plate, and the rear end of each guide plate is fixed to the rear side plate, so that a guide path is formed between the pair of guide plates. It is characterized in that a slit cut from the end edge is formed at least in a portion of the rear side plate that corresponds to the side surface of the guide path.

Further, in the structure of the transfer drum according to the second invention, a cylindrical transfer drum body, a front side plate attached to the front end of the transfer drum body and rotatably supporting the transfer drum, and a front side plate attached to the rear end of the transfer drum body. , a rear side plate rotatably supporting the transfer drum, and a moving means for moving the transfer drum main body, front side plate, and rear side plate in the drum axis direction of the transfer drum main body, and the transfer material to which an image is transferred during image transfer is The structure of the transfer drum is such that it is held by being wrapped around the circumferential surface of the transfer drum body, and at least the rear plate is cut out at a portion that corresponds to the side surface of the passage of the transfer material guided to a predetermined position of the transfer drum body. It is characterized by the presence of

<Function> In the structure of the transfer drum according to the first invention, when the transfer material jams in the guide path between the front side plate and the rear side plate, the transfer drum is moved forward in the drum axial direction from the main body of the apparatus. When the transfer drum is pulled out, the transfer material passes through the slit formed in the rear plate, so the transfer drum can be pulled out forward in the axial direction of the drum without the transfer material left in the guide path being caught on the rear plate.

In addition, in the structure of the transfer drum according to the second aspect of the present invention, the rear plate is cut out at the part that corresponds to the side surface of the transfer material passage, so even if a jam occurs, the transfer material will not get caught on the rear plate. The transfer drum can be pulled out forward in the axial direction of the drum.

<Example> Next, an example of the present invention will be described below with reference to the drawings.

FIG. 4 is a schematic cross-sectional view showing the schematic configuration of a full-color copying machine A to which an embodiment of the present invention is applied.

The full-color copying machine A is equipped with a document placement plate 3 for placing an original, and a reading sensor 5 for reading the contents of the document placed on the document placement plate 3. The reading sensor 5 has a built-in lamp 4 for illuminating the original. Further, a moving device (not shown) for moving the reading sensor 5 in the direction of arrow X, a laser scanning unit 6 that outputs a laser beam based on a signal given from the reading sensor 5, and a laser provided from the laser scanning unit 6 A photosensitive drum 7 is provided on which an electrostatic latent image is formed by being exposed to light. Near the photoreceptor drum 7, four developing devices 81, 82, 83, 84 for magenta, cyan, yellow, and black are provided to develop the electrostatic latent image.
The developing devices 81 to 84 are vertically shiftable by the elevator mechanism 10. One of the developing devices 81 to 84 is brought into contact with the photosensitive drum 7 by the elevator mechanism 10 .

The full-color copying machine A also includes a transfer drum body 11 that holds a sheet of paper when the toner image formed on the photosensitive drum 7 is transferred to the sheet of paper.

Further, the copying machine A includes a paper feed cassette 12 disposed inside the copying machine A, a manual paper feed port 14 disposed at the lower side of the copying machine A, a transfer charger 15 for transferring the toner image on the photoreceptor drum 7 onto paper, A separation charger 16 and a separation claw 17 for separating the paper to which the toner image has been transferred, a transfer drum cleaner 18 to remove foreign matter from the surface of the transfer drum body 11, and a conveyor for transporting the paper to which the toner image has been transferred. A belt 19 and a fixing device 20 for fixing the toner image on the paper are provided.

FIG. 1 is a perspective view showing the transfer drum 1 pulled out from the copying machine A, and FIG. 2 is a sectional view taken along the line ■-■ in FIG. 1, showing the transfer drum 1 pulled out from the copying machine A. It is shown fitted into a copying machine A, rather than a

The transfer drum 1 includes a transfer drum main body 11, a front side plate la
The configuration includes a rear side plate 1b and a linear rolling bearing IC. The transfer drum main body 11 is used to wrap and hold the paper P around its circumferential surface, and has a cylindrical shape.

The front side plate 1a and the rear side plate 1b are attached to the front and rear end surfaces of the transfer drum body 11, respectively, and rotatably support the transfer drum body 11. Further, the linear roller bearing IC is attached to the front side plate las, the rear side plate 1b, and the copying machine main body A1.

The transfer drum 1 is attached to the full-color copying machine main body A1 in a state that it can be pulled out in the axial direction forward of the transfer drum main body 11 by the linear rolling bearing IC (see FIG. 1).

Paper is supplied to the transfer drum 1 via a guide path 13. The guide path 13 guides the paper P to a predetermined position on the transfer drum main body 11, and is formed between a pair of guide plates 13C and 13d arranged at a predetermined interval.

Further, the front ends of the guide plates 13c and 13d are connected to the front side plate 1a,
The rear ends are respectively attached to the rear side plates 1b. The portions of the front side plate 1a and the rear side plate 1b that correspond to the side surfaces of the guide path 13, that is, the front side plate 1a and the rear side plate 1
Guide plate 13c of b.

The portion between 13d is cut and removed from the edge of each side plate 1a, lb to form a slit 1d.

With the transfer drum 1 having the above configuration, as shown in FIG. 3, the guide path 1 is formed between the front side plate 1a and the rear side plate 1b.
3, when the transfer drum 1 is slid forward in the drum axis direction from the copying machine main body A1 and pulled out, the paper P remaining in the guide path 13 is formed on the rear side plate 1b. Since the transfer material P passes through the slit 1d, the transfer material P passes through the rear plate 1b.
The transfer drum 1 can be pulled out without getting caught.

In the embodiment shown in FIGS. 1 and 2, the slit IC is formed on the front side plate 1a and the rear side plate 1b, but if the slit IC is formed on at least the rear side plate 1b, the embodiment shown in FIG. If a jam occurs as shown, paper P
The transfer drum 1 can be pulled out forward in the axial direction of the drum without getting caught.

Further, as another embodiment of the present invention, as shown in FIGS. 5 and 6, a portion corresponding to the side surface of the guide path 13 formed between the front side plate 1a and the rear side plate 1b is cut out,
Of the pair of guide plates 13C113d, the guide plate 13c closer to the transfer drum body 11 is attached to the edge portions of the front side plate 1a and the rear side plate 1b, and the guide plate 13d farther from the transfer drum body 11 is attached to the copying machine body. It may be attached to A1.

In this case, as shown in FIG.
If a jam occurs in the guide path 13 formed between 3c and 13d, even if the transfer drum 1 is pulled forward in the axial direction of the drum, the portion of the rear plate 1b that corresponds to the side surface of the guide path 13 will be cut out. , the paper guide plate 13d is the front side plate 1
a and the upper outer periphery of the rear side plate 1b, the transfer drum 1 can be pulled out forward in the drum axial direction without the paper P being caught on the rear side plate 1b.

In the embodiment shown in FIGS. 5 and 6, the portions of the front side plate 1a and the rear side plate 1b that correspond to the side surfaces of the guide path 13 are cut out, but at least the portions of the rear side plate 1b that correspond to the side surfaces of the guide path 13 are cut out. If the notch is provided, even if a jam as shown in FIG. 7 occurs, the transfer drum 1 can be pulled out forward in the axial direction of the drum without getting caught by the paper P.

Furthermore, as another embodiment, as shown in FIGS. 8 and 9, a portion corresponding to the side surface of the guide path 13 formed between the front side plate 1a and the rear side plate 1b is cut out, and the guide plate Both 13c and 13d may be attached to the copying machine main body A1.

In this case, as shown in FIG.
3d, the transfer drum 1 can be pulled out forward in the axial direction of the drum without getting caught on the paper P.

In the embodiment shown in FIGS. 8 and 9, the portions of the front side plate 1a and the rear side plate 1b that correspond to the side surfaces of the guide path 13 are cut out, but at least the portions of the rear side plate 1b that correspond to the side surfaces of the guide path 13 are cut out. If the notch is provided, even if a jam as shown in FIG. 10 occurs, the transfer drum 1 can be pulled out forward in the drum axis direction without being caught by the paper P.

<Effects of the Invention> As described above, according to the structure of the transfer drum according to the first invention and the second invention, when a jam occurs with the transfer material between the front side plate and the rear side plate, the transfer Since the transfer drum can be pulled out without the jammed transfer material getting caught on the drum, the jam can be easily cleared.

[Brief explanation of the drawing]

FIG. 1 is a perspective view of the main parts of an embodiment of the transfer drum according to the present invention, showing a state in which it is pulled out from the main body of the copying machine, and FIG.
A schematic sectional view taken along the line ■-■ in FIG. 1 showing the state in which the transfer drum shown in the figure is fitted into the main body of the copying machine, and FIG. 4 is a schematic sectional view of an image forming apparatus to which the transfer drum is applied; FIG. 5 is a schematic perspective view showing another embodiment pulled out from the main body of the copying machine;
6 is a schematic sectional view showing the embodiment shown in FIG. 5 fitted into the main body of the copying machine; FIG. 7 is an enlarged sectional view showing the state in which a paper jam has occurred in the embodiment; 8
FIG. 9 is a perspective view of a main part showing a state in which a transfer drum according to another embodiment is pulled out from a copying machine main body, and FIG. 9 is a schematic diagram showing a state in which the transfer drum shown in FIG. 8 is fitted into a copying machine. FIG. 10 is an enlarged sectional view showing a state in which a paper jam occurs in the above embodiment, FIG. 11 is a schematic sectional view showing a conventional transfer drum, and FIG.
FIG. 3 is an enlarged sectional view showing a case where a paper jam occurs in the transfer drum of FIG. DESCRIPTION OF SYMBOLS 1... Transfer drum, 1a... Front side plate, 1b... Rear side plate, 1c... Slit, 11... Transfer drum body, 13... Guide path, A... Full color copying machine, P.
...Paper. Patent applicant: Sanda Kogyo Co., Ltd. Agent Patent attorney: Kosaku Inaoka (and 2 others) 1... Transfer drum 1b... Rear side plate 1C... Slit 11... Transfer drum body 13... Guide Path P...Paper Fig. 2, Fig. 3b 1b...Rear side plate IC...Slit 11...Transfer drum body 13...Guide path Fig. 6, Fig. 7, Fig. 1b...Rear side plate 1c ...Slit 11...Transfer drum body 13...Guide path P...'Paper Fig. 9

Claims (1)

[Scope of Claims] 1. A cylindrical transfer drum body, a front side plate attached to the front end of the transfer drum body to rotatably support the transfer drum, and a front side plate attached to the rear end of the transfer drum body to enable the transfer drum to rotate freely. includes a moving means for moving the transfer drum body, the front side plate, and the rear side plate in the direction of the drum axis of the transfer drum body; The structure of the transfer drum is such that the transfer drum is held by being wrapped around the transfer drum, and a guide member for guiding the transfer material to a predetermined position on the transfer drum body is disposed between the front side plate and the rear side plate, and the guide member includes a pair of guide plates facing each other at a predetermined interval, the front end of each guide plate is fixed to the front side plate, the rear end of each guide plate is fixed to the rear side plate, and a guide path is formed between the pair of guide plates. A structure of a transfer drum characterized in that a slit cut from an edge is formed at least in a portion of the rear plate that corresponds to the side surface of the guide path. 2. A cylindrical transfer drum body, a front side plate attached to the front end of the transfer drum body and rotatably supporting the transfer drum, a rear side plate attached to the rear end of the transfer drum body and rotatably supporting the transfer drum; It includes a moving means for moving the transfer drum main body, the front side plate, and the rear side plate in the direction of the drum axis of the transfer drum main body, and is configured to wrap and hold the transfer material to which the image is transferred at the time of image transfer around the circumferential surface of the transfer drum main body. A structure of a transfer drum, characterized in that at least the rear plate is cut out at a portion corresponding to a side surface of a passage for transfer material guided to a predetermined position of a transfer drum main body.