JPS6215565A - Image forming device - Google Patents

Abstract

PURPOSE:To facilitate the inserting operation of an electric wire to each distribution wiring pulley by providing a center hole for electric wire insertion, an end surface groove cut radially from the opening edge of the center hole, and an outer peripheral hole communicating with the end surface groove to each distribution wiring pulley fitted to a one-side rotary support shaft end of each developing device. CONSTITUTION:Plural electric wires 86-89 connected to feed parts of respective developing devices 14a-14d are led out of opening ends of center holes 80a of respective distribution wiring pulleys 81-84 temporarily and then tip parts of the electric wires 86-89 are inserted into one desired groove part of cross- shaped end surface grooves 81a-84a and led out of one outer peripheral hole 80c opened in the groove end. Consequently, the inserting operation of the electric wires 86-89 to the distribution wiring pulleys 81-84 and the wiring operation of the respective electric wires 86-89 are facilitated.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to an image forming apparatus such as a color copying machine equipped with a plurality of developing devices containing developers of different colors.

[Technical background of the invention and its problems] Conventionally, a plurality of developing devices containing different color developing devices are supported on a rotating frame so that they can revolve while being kept in a parallel state. An image forming apparatus is known in which one of the developing devices is selected and a latent image on an image bearing member is developed by the selected developing device (for example, Japanese Patent Application Laid-Open No. 57/1989). - Publication No. 111555).

Such an image forming apparatus has a developing bias and a developer (toner) ratio i! ! In order to control the temperature, it is necessary to make an electrical connection between the main body of the device and the developing device. Conventionally, this electrical connection was made using a connector that slides on the side of the developing device. There were problems such as poor contact and wear of connector terminals.

[Object of the invention] This invention has been made in view of the above circumstances.
The purpose of this is to ensure that the electrical connection between the revolving structure developing device and the main body of the device can be made by directly connecting electric wires without using a conventional connector, and to prevent electrical contact failures and connector terminals. Another object of the present invention is to provide an image forming apparatus with a new structure that does not cause problems such as wear and tear, and a second object is to provide an image forming apparatus in which the above-mentioned wiring work of the electric wires can be easily performed.

[Summary of the invention] In order to achieve the first and second objects, the present invention has the following features:
A plurality of developing devices containing developers of different colors are supported by a rotating frame so as to be able to revolve while being kept in a parallel state, and one developing device from among the plurality of developing devices is selected by rotation of the rotating frame, In the image forming apparatus in which the latent image on the image carrier is developed by the selected developer, the drive mechanism of the rotary frame is constructed as a forward and reverse rotation drive mechanism in which the developer does not revolve more than one revolution. , a plurality of holes each having a center hole for inserting an electric wire, an end groove cut in a radial direction from the opening end of the center hole, and an outer circumferential hole communicating with the end groove at the end of the rotation shaft for the one-side rotation frame of each developer; Install the distribution wiring pulley so that it rotates together with each developer (that is, it is rotatably loosely inserted into the central rotating shaft of the rotating frame and fixed so that it does not rotate with respect to the support member on one side of the rotating shaft). One centralized wiring pulley is provided into which electric wires can be inserted through the plurality of outer peripheral holes, and the plurality of electric wires connected to the current-carrying part of each developer are connected to the distribution wiring pulley. passing through the center and extending outward from an end groove of the distribution wiring pulley and a peripheral hole communicating with the end surface;
After being wrapped around the outer circumference of the centralized wiring pulley in an angular range corresponding to the forward and reverse rotation angles of the rotating frame, it is passed through the outer peripheral hole of the centralized wiring pulley into the pulley and connected to the main body of the device. This is a characteristic feature.

[Embodiment of the Invention] An embodiment of the present invention will be described below with reference to the drawings. FIG. 2 shows an overall configuration diagram of a color copying machine which is an example of an image forming apparatus according to the present invention, in which 1 indicates the copying machine main body;
Reference numeral 2 denotes a document table fixed to the upper surface of the main body 1, and the document set on the document table 2 is exposed to an exposure lamp 3 and mirrors 4, 5, . ．． An optical system consisting of 6 is configured to perform exposure scanning by reciprocating along the lower surface of the document table 2.

In this case, the mirror 5.6 moves at half the moving speed of the mirror 4 so as to keep the optical path length constant.

The light reflected from the original by the scanning of the optical system (the light reflected from the original by the light irradiation of the exposure lamp 3) is reflected by the mirror 4-
．． 5.6, passes through the lens block 7 for setting the copying magnification, is further reflected by the mirrors 8, 9.10, is guided to the photosensitive drum 12 as an image carrier through the slit 11, and is the image of the original. An image is formed on the surface of the photoreceptor drum 12.

The photosensitive drum 12 rotates in the direction indicated by the arrow, and the surface is first charged by the charger 13, and then the image of the document is exposed to slit light to form an electrostatic latent image. The latent image is configured to be visualized by applying developer (toner) by a developing device 14, which will be described later.

On the other hand, the paper P is taken out one by one from the paper cassette 15 by the paper feed roller 16, passed through the paper guide path 17, guided to the outside of a pair of registration rollers 18, aligned by the registration rollers 18, and transferred to the image transfer section. It is configured as follows: The paper feed cassette 15 is detachably provided at the lower right end of the main body 1 of the apparatus.

Then, the paper P sent to the image transfer section is transferred to the transfer charger 19.
By coming into close contact with the surface of the photoreceptor drum 12 at the portion , the toner image on the photoreceptor drum 12 is transferred by the action of the charger 19 . Then, the paper P to which this toner image has been transferred is electrostatically peeled off from the photoreceptor drum 12 by the action of the peeling charger 20 and conveyed by the conveyor belt 21, and then transferred to the fixing device 22 provided at the end thereof. The transferred image is fixed by passing through this area. Then, the paper P after fixing is sent to a pair of paper ejection rollers 24 by a pair of transport rollers 23, and the paper P is sent to a pair of paper ejection rollers 24 by the paper ejection rollers 24.
It is configured to be discharged onto an outside tray 25. Further, after the photosensitive drum 12 has been transferred, residual toner on the surface thereof is removed by a cleaner 26, and after that, the afterimage is erased by a static elimination lamp 27, and the photosensitive drum 12 returns to its initial state.

A guide selector 28 is provided between the transport roller 23 and the paper discharge roller 24 to switch the traveling direction of the paper P to be transported.
By the operation of this selector 28, the paper P sent by the transport roller 23 is guided to the paper ejection roller 24 during normal copying, and the paper P sent by the transport roller 23 is guided downward during multiple color copying. Curved paper guide path 2
A conveyance path 30 provided on the bottom side of the main body 1 via 9
The sheet is guided to the paper feed cassette 15 by this conveyance path 30, and is fed to the registration rollers 18 via a sheet guide path 31 that curves upward. That is, during multiple copying, the paper P is circulated as shown by the arrow in the figure.

The developing device 14 includes, for example, four developing devices 14a to 14.
d, and allows each of the developing units 14a to 14d to revolve while maintaining a parallel state (horizontal state) (However, in the case of the present invention, for example, 270° The developing device 14b is rotated in the forward and reverse directions within a revolution range of 100 degrees, so that one of the plurality of developing devices 14a to 14d, for example 14b, can be selected. Further, the developing device 14 is movable in the left-right direction (in the direction of approaching and separating from the photoreceptor drum 12) by a contacting and separating mechanism 50, which will be described later. That is, during the copying operation, as shown in FIG.
When the developing units 148 to 14d are selected, the developing units 148 to 14d are moved to a position a predetermined distance away from the photosensitive drum 12 as shown in FIG. will be held. When this selection operation is completed, the photosensitive drum 12 is moved again, and as shown in FIG.
is set opposite to the photoreceptor drum 12.

The detailed structure of the developing device 14 will be explained in FIGS. 4 to 7 below.
To explain with reference to the drawings, the developing device 14 includes a pair of left and right rotary shaft support members 34 and 35 that swing in the direction of the photosensitive drum 12 using a support shaft 33 fixed to the device main body 1 as a fulcrum, and The rotating frame 37 includes a rotating shaft 36 supported between members 34 and 35, and a pair of left and right rotating frames 37 and 38 that are fixed to the rotating shaft 36 and rotate integrally about the rotating shaft. Between .degree. 40d, 41a-41d
It is supported by a shaft.

Each of the developer rotation support shafts 40a to 40d supported by the right rotation frame 38 has a planetary pulley 4 at each shaft end.
2a to 42d are attached, and the rotating frame 37
．． A center hole of a sun pulley 42 fixed to the support member 35 is rotatably inserted into the center rotation shaft 36 of the support member 38 . between the planetary pulleys 42a and 42b attached to the developer rotation support shafts 40a and 40b and the sun pulley 42, which is fixed to the support member 35 and rotatably inserted into the frame center rotation wheel 36; Planetary bullies 42 attached to the developer rotation support shafts 40c and 40d.
Between c and 42d and the sun pulley 42, two timing belts 43 and 44 are hung as shown in FIGS. 1 and 7, with the sun pulley and the planetary pulley being assembled on three sides. Note that a drive pulley 4 is attached to the shaft end of the rotating shaft 36.
5 is attached, and a pulley 47 attached to the rotating shaft of the drive pulley 45 and a reversible motor 46 for revolving the developing device (this motor 46 is fixed to the support member 35 as shown in FIG. 1). A timing belt 48 is hung between them, and constitutes a rotational drive mechanism 49 for a rotary frame 37, 38 in which the developing devices 14a to 14d rotate forward and backward within a revolution range of 270 degrees, for example, without revolving more than one revolution. .

Note that the sun pulley 42 has two timing bells 1 to 1.
43 and 44 as shown in FIG. 1, this sun pulley 42 and each of the planetary pulleys 42a
-42d both have the same outer diameter. Therefore, when the rotating frames 37 and 38 are rotated by the developing device drive mechanism 49, the planetary pulleys 42a to 42d do not rotate on their own axis but revolve within a rotation range of one rotation or less, so that each of the developing devices L4a to 42d revolves within a rotation range of one rotation or less. 14d always revolves at the same angle, that is, while maintaining a parallel state, within a rotation range of one rotation or less (in the case of the embodiment, a forward and reverse rotation range of 270 degrees).

Such an operation is necessary to control the posture of the developing units 14a to 14d containing powdered developer (toner). For example, the first developing device 14a is filled with black toner, the second developing device 14b is filled with red toner, the third developing device 14c is filled with green toner, and the fourth developing device 14d is filled with green toner. Contains blue toner.

Reference numeral 5o shown in FIG. 4, FIG. IM
This approach/separation mechanism 50 is constructed as follows. That is, a pair of left and right arms 51.52 are disposed near the lower end of the support member 34.35 and substantially perpendicular to the support member 34.35. At one end of the arm 51, 52 located on the photoreceptor drum 12 side, there is a long hole 51 extending in the direction of approaching and separating from the photoreceptor drum 12.
a, 52a are provided, and these elongated holes 51a, 52
A bushing 53, 53 is rotatably and movably fitted in a. Further, a spring 5 is provided around the bushings 53, 53 for biasing the bushings toward the photosensitive drum 12.
4.54 is being strung up. Connecting pins 34a and 35a fixed to the support members 34 and 35 are rotatably fitted into the center holes of the bushes 53 and 53, respectively. Further, a bearing 55 is provided at the other end of the arm 51.52.
．． 55 is fitted, and via this bearing, the bin 56.
56, links 57, 57, and shirts 1 to 58. A crank mechanism 60 is connected thereto. Furthermore, the shaft 58 is provided with a pulley 61. timing belt 62. Torque from a motor 64 is transmitted via a pulley 63. Note that the shaft 58 has a bearing pair 5.
9.59, and the motor 64 is rotatably held on the apparatus main body 1 side by a mounting base (not shown).

When the developing device 14 is located at a developing portion position close to the photosensitive drum 12 as shown in FIG. ing. That is, - the line connecting the support shaft 33 and the rotating shaft 36 is substantially perpendicular, and the vector of gravity is positioned at the vertical line passing through the support shaft 33. At this time, the 9th
As shown in detail in Figure (a), the positions of the bushes 53 and 53 are such that they do not touch either end of the elongated holes 51a and 52a, and the positions of the bushes 53 and 53 are such that they are not in contact with either side of the elongated holes 51a and 52a. ) is a positioning fitting 74 attached to this developing unit 14b (this fitting 74 is attached to all developing units 14.a to 14d).
However, only the positioning metal fitting 74 of the selected developing device 14b) is butted against the positioning bin 75 provided on the apparatus main body 1 side, so that the photosensitive drum 12 and the developing device 14b are The gap G is defined as shown in FIG. Also, in this state,
The motor 64 is stopped rotating so that the link 57 (bin 56) faces the photosensitive drum 12 side most.

When the motor 64 starts rotating in a predetermined direction from the state shown in FIG. 9(a), first, as shown in FIG. 9(b), the left end portions of the elongated holes 51a and 52a are brought into contact with the bushes 53.
, 53, the developing device 14 begins to move away from the photosensitive drum 12. Then, when the motor 64 further rotates,
As shown in FIG. 9(C), the support member 34°35 is tilted,
As shown in FIG. 8, the developing device 14 is separated from the photosensitive drum 12 and is in a position where it can revolve.

FIG. 10 is a cross-sectional view showing the internal structure of each of the developing units 14a to 14d. Each of the developing units 14a to 14d is a developing unit containing, for example, developer E, which is a mixture of toner and magnetic carrier in an appropriate ratio. a container case 141, an agitator 147 for agitating the developer E in this case, and this agitator 14.
A developing roller 145 with a built-in magnet that transports the developer E stirred by 7 and supplies the developer E onto the photoreceptor drum 12;
The developer case 141 is provided with a doctor blade 146 for regulating the layer thickness of the developer E conveyed toward the developer E, and a toner replenishment roller 142 for replenishing the toner T in the developer E and a toner replenishment port 143 in the upper part of the developer case 141. Toner hopper 1 with
44 are provided.

Furthermore, a developing roller gear 145a is attached to the shaft of the developing roller 145.
The stirrer gear 14 is attached to the shaft of the stirrer 147.
7a are engaged as shown in FIG. Further, a replenishment roller gear 142a is meshed with the agitator gear 141a via an idle gear 148.

On the other hand, the apparatus main body 1 side is provided with a drive gear 71 attached to the shaft of a drive motor 70 and an idle gear 72 that meshes with the drive gear 71. When the developing roller approaches the photosensitive drum 12, the developing roller gear 145 is connected to the idle gear 72.
a meshes with each other as shown in FIG. 11, and the developing roller gear 145a
The driving force is transmitted in the order of → stirrer gear 147a → idle gear 148 → replenishment roller gear 142a. Note that an electromagnetic spring clutch (not shown) is interposed between the replenishment roller gear 142a and the toner replenishment roller 142, and the transmission of driving force is interrupted by magnetizing and demagnetizing the electromagnetic spring clutch. Toner T can be replenished intermittently.

1, 12, and 13 show an electric wire wiring device between each of the developing devices 14a to 14d and the apparatus main body 1, which is the gist of the present invention.
Rotation support shaft 4 for one side rotation frame 37 of a to 14d
A plurality of distribution wiring pulleys 81 to 84 (with the same outer diameters) are attached to the shaft ends of 1a to 41d (the rotating shafts are hollow) so as to rotate together with the respective developing devices 14a to 14d. Each of the wiring pulleys 81 to 84 has a center hole 80a for inserting an electric wire, a female surface groove 80b cut in the radial direction from the open end of the center hole 80a, and an outer peripheral hole 80c communicating with the end surface groove 80b), Said rotating frame 37.3
One piece having an outer diameter equal to that of the distribution wiring pulleys 81 to 84 is rotatably loosely inserted into the center rotating shaft 36 of the rotary shaft 36 and fixed so as not to rotate with respect to the one side support member 34 of the rotating shaft 36. Centralized wiring pulley 85 (this wiring pulley 85
is configured such that electric wires 86 to 8'9 can be inserted through a plurality of outer circumferential holes 85c)', and a magnet energization part of each developing device 14a to 14d, for example, a magnet of the developing roller 145. A plurality of electric wires 86 to 89 connected to the parts are passed from inside the developing unit one-sided rotation support shafts 41a to 41d through the center hole 80a of the distribution wiring pulleys 8l-L84 to the end grooves 80b of the distribution wiring pulleys 81 to 84. The rotary frames 37 and 38 extend outward from the outer peripheral hole 80C communicating with this end groove, and are attached to the outer periphery of the centralized wiring pulley 85.
After being wrapped in an angular range of, for example, 270 degrees corresponding to the forward and reverse rotation angles of Fixed cylinder 8'5 for member 34
A from a wire through hole (not shown) of the supporting member 34 that passes through a gap 90 between the rotating shaft 36 and the rotating shaft 36 and opens into the gap.
As shown in the figure, it is configured to extend outward and be connected to an outlet or the like provided on the device main body 1 side.

In the case of this embodiment, the end grooves 80b of the distribution wiring pulleys 81 to 84 are formed as cross-shaped grooves, and the outer peripheral holes 80c of the distribution wiring pulleys 81 to 84 are formed in the shape of the cross-shaped end grooves 80.
By selecting any one of the outer peripheral holes 80C, each of the electric wires 86 to 89 can be passed through the pulley end groove 80b to the outside as shown in FIG. 12. I'm trying to get it out. That is, a plurality of electric wires 8 are connected to the current-carrying parts of each of the developing devices 14a to 14d.
6 to 89 into the center hole 80a of each distribution wiring pulley 81 to 84.
After taking it out from the open end, remove the wires 86 to 89.
The tip of the cruciform end groove 81a to 84a is inserted into a desired position.
One outer peripheral hole 8 inserted into two grooves and opened at the end of the groove.
The electric wires 86 to 89 can be drawn outward from the distribution wiring pulleys 81 to 84, and
The advantage is that the above-mentioned wiring work for each of the electric wires 86 to 89 can be easily performed.

Therefore, the electric wires 86 to 89 connect to the plurality of developing units 14a to 14
For example, when developing device 14b among 4d is selected,
The rotating frame 3 is in the state where the pulley is wound as shown in FIG. 13(a), and in this state, the rotating frame 3
7. When 38 is rotated 90 degrees counterclockwise in FIG. 13, the pulley winding state of the electric wires 86 to 89 becomes as shown in FIG. 13(b), and in this state, the next developing device 14d is selected. When the rotating frames 37 and 38 are further rotated 90 degrees counterclockwise in FIG. 13, the electric wires 86 to 89 are wound around the pulleys as shown in FIG. 13(C). The rotating frame 37 selects the developing device 14c.
．． When 38 is further rotated 90 degrees counterclockwise in FIG. 13,
The state in which the electric wires 86 to 89 are wound around the pulleys is shown in Fig. 13(d).
It becomes as shown in . As is clear from the rotational operation diagrams shown in FIGS. 13(a) to 13(d), which developing devices 14a to 14
Even when option d is selected, the electric wires 86 to 89 that directly connect the developing device to the apparatus main body 1 side are always connected to prevent slack or tension from occurring between the central wiring pulley 85 and the distribution wiring pulleys 81 to 84. Maintains good wiring wrapping condition.

Next, the operation of the entire image forming apparatus including the developing device 14 as described above will be explained. In the case of multiple copy mode, firstly, if you want to copy the first original onto the document table 2, for example, in red color, first, in order to select the developer 14b containing red colors 1 to 1, @14 in the direction away from the photoreceptor drum 12 (to the right) and
Set it to the state shown in the figure.

When the movement of the developing device 14 is completed in this way, the reversible motor 46 for revolution is operated to rotate the rotating frame 37° 38 in forward and reverse directions, thereby allowing each developing device 1 to move as described above.
4a to 14d are kept in a parallel state and revolved within a predetermined rotation range, and the developing device 14b to be selected is connected to the photosensitive drum 1.
When it faces 2, it stops its revolution. When this operation is completed, the developing device 14 is moved to the photosensitive drum 12 side, and as shown in FIG.
The photoreceptor drum 4b is set in a state where it approaches the photoreceptor drum 12 and faces each other. With the above operation, the selection operation of the developing unit 14b corresponding to the selected and designated color is completed, and red copying becomes possible.

Next, a copying operation is started, and red copying is performed using the developing device 14b. That is, exposure is performed as the original is scanned, and the photoreceptor drum 12 formed by this exposure
The upper electrostatic latent image is visualized by the developing device 14b, and this visualized toner image is transferred onto the paper P to be supplied. Next, the paper P on which the toner image has been transferred is sent to a fixing device 22 by a transport belt 21, fixed under pressure, and sent to a transport roller 23. Then, when the paper P that has been fixed is sent to the position of the selector 28 by the transport roller 23, since the selector 28 is set at the solid line position in FIG. It is turned along the guide path 29 and sent to the conveyance path 30. This conveyance path 30 conveys the paper P to the front side of the registration rollers 18, and temporarily stops the paper P at that position to prepare for the copying operation of the next color.

Next, the second original is set, and in order to stop multiple copying, the multiple copying mode is canceled and the developing device 14a containing black toner is removed by the same selection operation as described above.
is selected, and black copying becomes possible. Note that if you want to continue multiple copying again here, you can leave the multiple copying mode as it is.

In this way, when the multiple copy mode is canceled, the same copying operation as described above is started, and black copying is performed using the developing device 14a. In this case, a black copy is made superimposed on the previously made red copy.

The paper P that has been overlapped is transferred to the transport roller 23.
When the paper P is fed, the selector 28 has been switched to the position shown by the broken line in FIG. Multiple copies are performed in the manner described above. Note that by continuing to use the multiple copying mode without canceling it, it is also possible to duplicate blue and green colors.

Note that although the above embodiment describes the case where the present invention is applied to a color copying machine, the present invention is not limited thereto, and may be applied to other image forming apparatuses such as electronic printers, facsimile machines, or printing machines. I can do it.

[Effects of the Invention] The image forming apparatus of the present invention supports a plurality of developing devices containing developers of different colors on a rotating frame so as to be able to revolve while keeping them in a parallel state. One of the developing devices is selected and the latent image on the image carrier is developed by the selected developing device, and the rotational drive mechanism of the rotating frame is rotated so that the developing device revolves one revolution or more. The developing unit is configured as a drive mechanism for forward and reverse rotation, and has a central hole for inserting electric wires at the end of the rotating shaft for the one-side rotating frame of each developer, an end face groove cut in a radial direction from the open end of the center hole, and the end face. A plurality of distribution wiring pulleys having peripheral holes communicating with the grooves are attached to rotate together with each developing unit, and are rotatably inserted into the central rotating shaft of the rotating frame, and a supporting member on one side of the rotating shaft. A centralized wiring pulley is provided through which electric wires can be inserted through a plurality of outer peripheral holes that are fixed so as not to rotate. An angle corresponding to the forward/reverse rotation angle of the rotary frame extends outward from the end groove of the distribution wiring pulley through the center hole of the distribution wiring pulley and the outer peripheral hole communicating with the end groove, and extends outward from the outer periphery of the central wiring pulley. After being wrapped around the central wiring pulley, it is passed through the outer circumferential hole of the pulley and connected to the main body of the apparatus, which makes it possible to connect the developing unit with the revolving structure to the main body of the apparatus. Image formation with a new structure, which has the effect of ensuring that the electrical connection between the two is made by directly connecting electric wires without using a conventional connector, and does not cause problems such as poor electrical contact or wear of connector terminals. equipment can be provided.

Further, in the image forming apparatus of the present invention, the distribution wiring pulley attached to the end of one rotational shaft of each developing unit has a center hole for inserting an electric wire, an end face groove cut in the radial direction from the open end of the center hole, and an end face groove cut in the radial direction from the open end of the center hole. Since an outer peripheral hole is provided that communicates with the groove, once the multiple electric wires connected to the current-carrying parts of each developer are taken out from the center hole opening end of each distribution wiring pulley, the tips of these electric wires are removed. It can be inserted into the end face groove and pulled out from one outer circumferential hole 80C opened at the end of the groove, which makes it easy to insert the electric wire into each distribution wiring pulley and, if necessary, to wire each electric wire. It also has the effect of being able to be carried out.

[Brief explanation of the drawing]

FIG. 1 is a partially cutaway side view of the developing device showing the main parts of the apparatus of the present invention, 2nd figure is an overall schematic vertical sectional view of a color copying machine to which the apparatus of the present invention is applied, and 3 A schematic vertical cross-sectional view showing the copying machine in a state when the developing device is selected, FIG. 4 is a front view of the developing device, FIG. 5 is a perspective view showing the developing device approach and separation mechanism, and FIG. 6 is a diagram of the developing device. A front view showing the rotating frame, FIG. 7 is an explanatory view showing the state in which the timing belt is stretched, FIG. 8 is a front view showing the state in which the developing device is separated from the photoreceptor drum, and FIGS. C) is an explanatory diagram of the operation of the approaching/separating mechanism, FIG. 10 is a central vertical sectional view showing the internal structure of the developing device, FIG. 11 is a rear view showing the drive system of the developing device, and FIG. 12 is the gist of the present invention. FIGS. 13(a) to 13(d) are perspective views of the electric wire wiring portion, and FIGS. 13(a) to 13(d) show diagrams of the rotational operation of the electric wire wiring portion when selecting a developing device. DESCRIPTION OF SYMBOLS 1... Image forming apparatus main body, 12... Image carrier (photosensitive drum), 14... Developing device, 14a to 14d...
・Developer, 34, 35...Rotary shaft support member, 36・
... Center rotation axis of the rotating frame, 37.38... Rotating frame, 40a to 40d... Right side rotating support shaft of the developing unit,
41a to 41d...Developer left side (one side) rotation support shaft, 4
9...Rotary frame rotation drive mechanism, 50...Developing device approach/separation mechanism, 81-84...Distribution wiring pulley, 80
a... Center hole for electric wire insertion of the same pulley, 80b... End face groove of the same pulley, 80c... Outer peripheral hole of the same pulley, 85
...Centralized wiring pulley, 85a...Fixed cylinder of the same pulley, 850...Peripheral hole of the same pulley, 86-89...Electric wire applicant's representative Patent attorney Takehiko Suzue Figure 5 Figure 6 Figure 7 Figure bb (C) 9th wJ 7υ Figure 13 rriC

Claims (2)

[Claims] (1) A plurality of developing devices containing developers of different colors are supported by a rotating frame so that they can revolve while being kept in a parallel state, and one of the developing devices is activated by the rotation of this rotating frame. In an image forming apparatus in which a latent image on an image carrier is developed by the selected developing device, the rotational drive mechanism of the rotating frame is a forward/reverse rotation drive mechanism in which the developing device does not revolve more than one revolution. configured as,
and a plurality of peripheral holes having a center hole for inserting an electric wire, an end groove cut in a radial direction from the open end of the center hole, and an outer circumferential hole communicating with the end groove at the end of the rotation shaft for the one-side rotating frame of each developer. A plurality of distribution wiring pulleys are attached to rotate together with each developing device, and are rotatably inserted loosely into the central rotating shaft of the rotating frame and fixed so as not to rotate with respect to a support member on one side of the rotating shaft. One central wiring pulley is provided through which electric wires can be inserted through the outer circumferential hole, and a plurality of electric wires connected to the current-carrying portion of each developing unit are distributed through the center hole of the distribution wiring pulley. The central wiring pulley extends outward from the end groove of the wiring pulley and the outer peripheral hole communicating with the end groove, and is wound around the outer periphery of the central wiring pulley in an angular range corresponding to the forward and reverse rotation angles of the rotating frame. An image forming apparatus characterized in that the image forming apparatus is connected to an apparatus main body by being passed through the pulley through an outer peripheral hole of the pulley. (2) The outer diameters of the distribution wiring pulley and central wiring pulley are
The image forming apparatus according to claim 1, wherein the image forming apparatus is equal to each other.