JP2001134032A - Image forming device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an image forming device capable of positioning a developing unit and a photoreceptor unit with much higher positioning accuracy and surely holding such positioning. SOLUTION: The developing unit 11 holding the specified number of developing devices is supported to be rocked in a holding unit 12 positioned in a main body and provided so that it can be pulled out and inserted in a front direction, and the unit 11 is positioned with respect to the photoreceptor unit 5 accurately positioned in the main body by abutting on the unit 5. Furthermore, when an operation lever is operated to be rotated, a rocking lock lever 37 presses the unit 11 to the unit 12 by pressing force generated by the toggle action of 1st and 2nd rocking link levers 33 and 35, whereby the unit 11 is held in a state where it abuts on the unit 12. Thus, the unit 11 is prevented from being separated from the unit 12.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a developing roller having a thin toner layer formed on a surface thereof at a certain distance from a photoreceptor at the time of non-development. It belongs to the technical field of an image forming apparatus in which a developing device is controlled so that a toner image is formed on a photoconductor in close proximity.In particular, a developing unit that holds a developing device and a photoconductor unit that holds a photoconductor are included. It belongs to the technical field of an image forming apparatus which is provided so as to be individually positioned.

[0002]

2. Description of the Related Art Conventionally, in an image forming apparatus such as an electrostatic copying machine or a printer, a thin toner layer is formed on the surface of a developing roller held by a developing device, and the developing roller is used as a photosensitive member when not developing. 2. Description of the Related Art There is known an image forming apparatus which forms a toner image on a photosensitive member by setting the developing position to a non-developing position separated from the photosensitive member by a certain distance or more and setting the developing position to be in contact with or close to the photosensitive member during development. ing. In such an image forming apparatus, the developing unit is slidably or rotatably held in a developing unit which is a housing, and the above-described separation / contact operation of the developing roller with respect to the photoconductor is performed using a power transmission control mechanism such as a clutch. ing.

When performing a predetermined operation on the developing device such as replacement of the developing device or replacement of the toner cartridge held by the developing device, the developing unit holding the developing device is connected to the main body of the image forming apparatus. I am pulling it out and working.

[0004]

In recent years, there has been a strong demand for an image forming apparatus to have a high speed image formation.
One of the ways to speed up image formation is, for example, to increase the image formation speed. For that purpose, it is necessary to reduce the time required for switching the developing roller between the non-development position and the development position. Therefore, the separation distance between the developing roller and the photoconductor at the non-development position of the developing roller is set to a minimum necessary distance that the toner on the surface of the developing roller is not attracted by the electric field applied to the surface of the photoconductor. are doing. However, if the separation distance between the developing roller and the photoconductor is set to a minimum as described above, when the developing unit is pulled out of the main body, the developing roller interferes with the photoconductor unit, and the developing unit is pulled out of the main body. In some cases, it is not possible.

Therefore, the developing unit is held by the holding unit so as to be swingable (rotatable) about a swing fulcrum shaft, and the developing unit is swung to bring the developing roller sufficiently away from the photosensitive member. It is conceivable that the holding unit is pulled out of the main body. However, when the developing unit is swung in this manner, it is difficult to position the developing unit with respect to the photoconductor, and the positioning accuracy between the photoconductor and the developing unit is reduced, and it is difficult to perform stable and good development. Become. In order to improve the positioning accuracy between the photoconductor and the developing unit, the accuracy of each component such as the developing device and the photoconductor is made as high as possible, and the mounting of the components to the main body frame such as the photoconductor unit, the developing unit and the holding unit is performed. It is conceivable to make the accuracy as high as possible.

For this purpose, (1) the developing roller is positioned on the developing device with a predetermined positioning accuracy, (2) the developing device is positioned on the developing unit with a predetermined positioning accuracy, and (3) the developing unit is positioned on the holding unit with a predetermined positioning accuracy. (4) Positioning the holding unit on the main body of the device with a predetermined positioning accuracy, (5) Positioning the photoconductor on the photoconductor unit with a predetermined positioning accuracy, (6) Mounting the photoconductor unit on the device It is necessary to position the main body with a predetermined positioning accuracy.

However, when positioning is performed in this manner, there are a wide variety of positioning members, and the accuracy of these positioning members and the mounting accuracy of the positioning members vary.
Since the developing unit and the photoconductor unit are individually positioned, it is extremely difficult to position the developing roller and the photoconductor with high positioning accuracy.

Further, even if the developing unit and the photoconductor unit are positioned with high positioning accuracy, the developing roller contacts the photoconductor at the time of development, and the developing unit is separated from the photoconductor unit by the reaction force. There is a possibility that the positioning between the developing unit and the photoconductor unit may be impaired due to the force. If the positioning is impaired in this way, there is no point in positioning the developing unit and the photoconductor unit before development.

The present invention has been made in view of such circumstances, and has as its object to perform the positioning between the developing unit and the photoconductor unit with higher positioning accuracy and to surely maintain the positioning. It is an object of the present invention to provide an image forming apparatus capable of performing the following.

[0010]

In order to solve this problem, the invention according to claim 1 is directed to a main body having a mounting position which is positioned and mounted in the main body and a pulling position which is pulled out of the main body. A holding unit that is provided so as to be able to be pulled out and inserted in the front-rear direction of the main body, a photosensitive body unit that is positioned and attached to the main body and holds a photosensitive body, A developing unit that is swung by an operation member and abuts on the photoconductor unit, is positioned with respect to the photoconductor unit, and further holds a predetermined number of developing units. Developing unit pressing means for pressing the developing unit against the photoreceptor unit with a predetermined pressing force while being in contact with the body unit; It is characterized in Rukoto.

Further, according to the present invention, the developing unit pressing means is provided on the holding unit so as to be swingable, and a pressing lever for pressing the developing unit against the photoreceptor unit; And a toggle means for applying a pressing force to the pressing lever in response to the pressing force.

[0012]

In the image forming apparatus according to the present invention, the developing unit is brought into contact with the photoreceptor unit to be positioned with respect to the photoreceptor unit.
When positioned, the developing unit is pressed against the photoreceptor unit by the pressing force of the developing unit pressing means. Therefore, even if the developing unit receives a reaction force when the developing roller comes into contact with the photoconductor during development, it does not separate from the photoconductor unit and maintains a stable contact state regardless of the magnitude of the reaction force. Will be done.

In particular, in the second aspect of the invention, since the developing unit is pressed and held by the photosensitive unit by the pressing force of the toggle means, the holding force is further increased. In addition, when the developing unit is pressed against the photoconductor unit, a click action is performed by the operation of the toggle means, and the click feeling is transmitted to the operation lever, and the developing unit is pressed against the photoconductor unit with a predetermined pressing force. You can see what was done.

[0014]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a diagram schematically showing an entire full-color image forming apparatus to which an example of an embodiment of the image forming apparatus of the present invention is applied, and FIG.
It is sectional drawing which follows a line.

As shown in FIGS. 1 and 2, a full-color image forming apparatus 1 of this embodiment is positioned and fixed on a main body 2 of the image forming apparatus 1, and a photosensitive member (hereinafter, referred to as an OPC).
An optical scanning system for exposing an image to be formed to a photoconductor unit 5 having a photoconductor cleaner 3 and an OPC 3 charged by a charging roller (not shown) disposed in the photoconductor unit 5. Exposure unit (hereinafter LSU)
1, a developing unit 11 for holding developing units 7, 8, 9, and 10 for yellow, magenta, cyan, and black, and a front side of the main body 2 (see FIG. 1). And a developing unit 7, which is attached to the developing unit 11 so as to be swingable, and a developing unit 7, 8, 9, 10
Intermediate transfer body 13 on which toner image on PC 3 is intermediately transferred
A transfer unit 14 for transferring an intermediate transfer image on the intermediate transfer body 13 to transfer paper, a fixing unit 15 for fixing a transfer image transferred to the transfer paper, and a transfer unit 14 which is set in the main body 2 and accommodates the transfer paper. A paper feed cassette 16, a manual paper feed tray 17 that is provided on the front side of the main body 2 (that is, the right side in FIG. 1) and stores transfer paper when the transfer paper is supplied manually, and a paper feed tray 17 that is provided above the main body 2 And a discharge tray 18 for storing transfer paper on which an image is formed.

The OPC 3 is positioned with high precision between the front and rear frames 5a and 5b of the photoreceptor unit 5, and is provided so as to be rotatable counterclockwise in FIG. On the surface of the OPC 3, a latent image of an image to be formed is formed by the LSU 6, and yellow, magenta, and magenta are respectively formed by the developing units 7, 8, 9, and 10.
Cyan and black toner images are formed. The photoconductor cleaner 4 removes and stores the residual toner on the OPC 3 after the intermediate transfer. Further, the photosensitive member unit 5 includes a positioning pin 5c.
, Is positioned and fixed to the front frame 2a of the main body 2 with high precision, and is positioned and fixed to the rear frame 2b of the main body 2 with high precision by the positioning pins 5d and 5e. Therefore, the OPC 3 is positioned with high precision with respect to the main body 2.

The yellow, magenta, cyan, and black developing units 7, 8, 9, and 10 are arranged along the outer periphery of the OPC 3 and in order from the rotation upstream side of the OPC 3.
The order in which the developing units 7, 8, 9, and 10 are arranged is not limited to the order described above, but may be set arbitrarily. Also, in the following description, for convenience of explanation, the order of the aforementioned colors, that is,
It is assumed that the developing units 7, 8, 9, and 10 are arranged in the order of yellow, magenta, cyan, and black.

Each of the developing units 7, 8, 9, and 10 is positioned with high precision in the developing unit 11 and is slidably or rotatably held. Each of these developing units 7,
Reference numerals 8, 9, and 10 denote toners for developing a latent image on the OPC 3, respectively.
Developing rollers 7a, 8a, 9a, and 10a for transporting to the PC 3 are provided. FIG. 1 shows the developing rollers 7a, 8a, 9a, and 10a of the respective developing units 7, 8, 9, and 10 all in contact with the OPC 3.
6A, 8A, 9A, and 10A are held at the non-development positions separated from the OPC 3 during non-development as shown in FIG. 6, and are set at the development positions in contact with or close to the OPC 3 in an appropriate order during development. Then, the latent image on the OPC 3 is developed.

Each developing roller 7a, 8a,
The contact or proximity operation and separation operation of 9a and 10a are as follows.
Each developing unit 7, 8, 9, 10 is connected to a mechanism such as a clutch (not shown).
Is performed by a driving means (not shown) such as a motor. In this case, the separation distance from the OPC 3 to the non-development position of each of the developing rollers 7a, 8a, 9a, and 10a at the time of non-development is set so that each developing roller 7a, 8a, 9a, 10a has a different Rollers 7a, 8a, 9a, 1
The distance is set to the minimum necessary such that the toner on the surface of Oa 3 is not attracted by the electric field applied to the surface of the OPC 3.

As shown in FIGS. 2 and 3, the developing unit 11 includes front and rear frames 11a and 11b and upper and lower stays 11a.
From c and 11d, a casing having a predetermined strength is formed. The developing unit 11 has an upper end and a side end on the side of the yellow developing device 7 that are the holding unit 12.
In addition, it is held by a swing fulcrum shaft 19 so as to be able to swing (rotate) around the swing fulcrum shaft 19. In this case, the swing fulcrum shaft 19 is connected to the front and rear frames 12a, 1 of the holding unit 12.
2b, these frames 12a, 12b are rotatably supported through the frames 12a, 12b, and the front and rear frames 11a, 11b of the developing unit 11 have through holes each having a diameter slightly larger than the diameter of the pivot shaft 19. 11e, 11f
Are formed, and penetrate through these through holes 11e and 11f in a state where the swing fulcrum shaft 19 is loosely fitted. Therefore, the developing unit 11 can swing independently of the rotation of the swing fulcrum shaft 19. By the swing of the developing unit 11, each of the developing rollers 7a, 8a, 9a, and 10a is set to be in contact with or close to the OPC 3 so as to be capable of developing, and any of the developing rollers 7a, 8a, 9a, 1
0a is also set to be sufficiently evacuable from the OPC3.

Similarly to the developing unit 11, the holding unit 12 has front and rear frames 12a and 12b and upper and lower stays 12c and 12c.
12d, it is formed as a housing having a predetermined strength. As shown in FIG. 3, the holding unit 12 is guided by a pair of guide rails 20 and 21 provided between the holding unit 12 and the main body 2 to move the developing rollers 7 a, 8 a, 9 a and 10 a from the OPC 3. It can be inserted into the main body 2 and can be pulled out from the main body 2 in a state of being sufficiently retracted.

One guide rail 20 is disposed between the side end of the holding unit 12 on the fulcrum shaft 19 side and the main body 2, and the other guide rail 20 is provided for the black developing device of the holding unit 12. It is arranged between the lower end on the 10 side and the main body 2. Each of the pair of guide rails 20 and 21 has the same configuration, respectively, as shown in FIG.
As shown in (b), a holding unit side rail 22 fixed to the holding unit 12 side, a main body side rail 23 fixed to the main body 2 side, and a middle provided between these two rails 22, 23. It consists of a rail 24.

The holding unit side rail 22 has both side ends 22a and 22b bent downward at substantially right angles to have a substantially U-shaped cross section, and both side ends 22a and 22b are respectively inwardly circular. It is curved in an arc. Also, the main body side rail 23 has both side end portions 23.
a, 23b are bent upward at substantially right angles to form a substantially U-shaped cross section, and both side ends 23a, 23b are each curved outward in an arc shape. Further, the intermediate rail 24 is formed in a substantially U-shaped cross-section by bending both side ends 24a and 24b upward at substantially right angles in the same manner as the main body side rail 23, but these side ends 24a and 24b are formed. Are further bent by 180 ° to form inner and outer ends 24a ₁ , 24a ₂ ; 24b ₁ ,
24b ₂ is formed as a double layer. Inside end 2
4a ₁ and 24b ₁ are each curved outwardly in an arc shape, and the outer side ends 24a ₂ and 24b ₂ are each curved inwardly in an arc shape.

Then, the holding unit side rail 22 is inserted into the intermediate rail 24 so that the arcuate curved portions of the both end portions 22a and 22b of the holding unit side rail 22 and the inner side end portions 24a ₁ and 24b ₁ of the intermediate rail 24 are provided. The arc-shaped curved portions are disposed so as to face each other with a predetermined gap, and the intermediate rail 24 is provided in the main body-side rail 23 with the arc-shaped curved portions of both side ends 23 a and 23 b of the main body-side rail 23. The portion and the arc-shaped curved portions of both outer end portions 24a ₂ and 24b ₂ of the intermediate rail 24 are disposed so as to face each other with a predetermined gap.

Further, on the upper surface of the intermediate rail 24, a substantially U-shaped first wire 25 is disposed in a direction orthogonal to the longitudinal direction of the intermediate rail 24. The first wire 25 has a central portion 25c fixed to the upper surface of the central portion 24c of the intermediate rail 24, and has both end portions 25a, 25b.
Are both end portions 22 of the holding unit side rail 22.
a, which is to be located in the center of the gap between the arc-shaped curved portion and two inner end 24a _1, 24b arc-shaped curved portion of the _first intermediate rail 24 of 22b. Balls 26 and 27 are supported at both end portions 25a and 25b of the first wire rod 25 so as to be rotatable around both end portions 25a and 25b, respectively. These balls 26, 27 are provided at both ends 22a, 22.
b, the curved surface and both inner side ends 24a ₁ , 24b ₁
And rolls between these curved surfaces in contact with the curved surfaces. A set of first wires 25 and balls 26 and 27 is provided on a predetermined number of intermediate rails 24 at predetermined intervals along the longitudinal direction.

Similarly, on the lower surface of the intermediate rail 24,
A substantially U-shaped second wire 28 is arranged in a direction orthogonal to the longitudinal direction of the intermediate rail 24. This second wire rod 28
The center part 28c is the center part 24c of the intermediate rail 24.
And is fixed to the lower surface of the
a and 28b are both end portions 23 of the main body side rail 23, respectively.
a, which is to be located in the center of the gap between the arc-shaped curved portion and the arcuate curved portions of the outer side end portion 24a _2, 24b ₂ of the intermediate rail 24 for 23b. Then, the second wire rod 28
Balls 29, 3 are attached to both side ends 28a, 28b, respectively.
0 is supported so as to be rotatable around both side ends 28a and 28b. These balls 29 and 30 are
a, 28b and both outer side end portions 24a ₂ ,
So that the roll between these curved surfaces in contact with the arcuate curved surface of 24b _2. A set of the second wire rod 28 and the balls 29, 30 is provided on the intermediate rails 24 of a predetermined number of sets at predetermined intervals along the longitudinal direction.

The holding unit side rail 22, the main body side rail 23 and the intermediate rail 24 are supported in the intermediate rail 24 in the vertical and horizontal directions in FIG. In addition, the intermediate rail 24 is incorporated so as to be relatively movable in the longitudinal direction, and the intermediate rail 24 is
In FIG. 4B, the balls 29 and 30 are supported by the balls 29 and 30 in the up, down, left and right directions, and are incorporated so as to be relatively movable in the longitudinal direction with respect to the main body side rail 23.

In order to stop and position the holding unit 12 when the holding unit 12 is mounted on the main body 2, one end of the intermediate rail 24 contacts a stopper 31 provided at one end of the main body side rail 23. 4, the direction in which the holding unit 12 is pushed into the main body 2, that is, FIG.
2A, the downward movement of the intermediate rail 24 is restricted, and one end of the holding unit side rail 22 abuts against a stopper 32 provided at one end of the intermediate rail 24, whereby the main body of the holding unit 12 is formed. The movement of the holding unit side rail 22 in the pushing direction toward the second unit 2 is restricted. Further, in order to stop and position the holding unit 12 when the holding unit 12 is pulled out from the main body 2 to the maximum, the intermediate rail 24 is positioned at a position shown in FIG. 4 (a), the holding unit side rail 22 is positioned relative to the intermediate rail 24 in the position shown in FIG. 4 (a). Further, relative movement in the pull-out direction is prevented.
In this manner, the holding unit side rail 22, the main body side rail 23, and the intermediate rail 24 are positioned at the maximum pulled-out position shown in FIG. It is telescopically expandable and contractible between positions abutting 31 and 32.

Further, as shown in FIG.
X of the developing unit 11 with respect to the photoconductor unit 5
3, a developing unit X-direction positioning portion 11 x for positioning in the left and right directions in FIG.
3, that is, a developing unit Y-direction positioning portion 11y for positioning in the vertical direction in FIG. Although these positioning portions 11x and 11y are formed by protrusions in the illustrated example, they can be formed by other appropriate means such as a surface.

On the other hand, the photoconductor unit 5 also has a photoconductor unit X-direction positioning portion 5x that positions the photoconductor unit 5 in the X direction with respect to the developing unit 11 and that can contact with the developing unit X-direction positioning portion 11x. A photoconductor unit Y-direction positioning portion 5y is provided, which is capable of abutting the developing unit Y-direction positioning portion 11y, by which the photoconductor unit 5 is positioned in the Y direction by abutting the developing unit Y-direction positioning portion 11y. . Although these positioning portions 5x and 5y are formed by surfaces in the illustrated example, they can be formed by other appropriate means such as projections similar to the positioning of the developing unit 11.

Then, as shown in FIG. 3, the developing unit 11 swings about the swing fulcrum shaft 19, and the developing unit X and the Y-direction positioning portions 11x and 11y respectively move the photosensitive unit X and the Y-direction. By contacting the positioning portions 5x and 5y, the photosensitive unit 5 and the developing unit 11
The positioning in the X and Y directions is directly performed with high precision without the intervention of the main body 2. As described above, in a state where the developing unit 11 is positioned in the X and Y directions with respect to the photoconductor unit 5, each of the developing units 7, 8,
The developing rollers 9a, 8a, 9a, 10a 9 and 10 are set with higher precision at the developing positions in contact with or close to the OPC 3, respectively. As described above, the developing unit X and the Y-direction positioning portions 11x and 11y constitute a first positioning portion provided in the developing unit 11.

When the developing unit 11 is positioned in the X and Y directions by swinging about the swing fulcrum shaft 19, the positioning of the developing unit 11 in the X and Y directions with respect to the swing center of the developing unit 11 is performed. Part 11x,
11y, the developing unit X
And the Y-direction positioning portions 11x and 11y are difficult to simultaneously contact the photoconductor unit X and the Y-direction positioning portions 5x and 5y, respectively, and only one of these developing units X and the Y-direction positioning portions 11x and 11y is provided. There is a possibility that the corresponding photoconductor unit X and the Y-direction positioning portions 5x and 5y do not come into contact with each other and the other positioning cannot be performed. For example, when the height from the swing center of the developing unit 11 to the developing unit Y-direction positioning portion 11y is increased due to the variation, the developing unit Y-direction positioning portion 11y contacts the photoconductor unit Y-direction positioning portion 5y. The developing unit 1
1 is held in a state of being lifted upward, and is not held in the original normal state (horizontal state). For this reason,
The developing unit X-direction positioning portion 11x does not come into contact with the photoconductor unit X-direction positioning portion 5x, and the X-direction positioning of the photoconductor unit 5 and the developing unit 11 cannot be performed.

Therefore, in the image forming apparatus 1 of this example, as described above, the developing unit 11
The diameters of the through holes 11e and 11f are set slightly larger than the diameter of the swing fulcrum shaft 19, and the swing fulcrum shaft 19 is
By loosely fitting e and 11f, a predetermined play is provided between the swing fulcrum shaft 19 and the developing unit 11. With this play, the variation in the positions of the developing unit X and the Y-direction positioning portions 11x and 11y with respect to the swing fulcrum of the developing unit 11 is absorbed, so that the developing unit X and the Y-direction positioning portions 11x and 11y respectively become photosensitive member units. It is possible to simultaneously contact the X and Y direction positioning portions 5x and 5y.

However, if there is a play between the pivot shaft 19 and the developing unit 11 as described above, if there is no such variation in the positioning portions 11x and 11y of the developing unit 11, or if the variation is large or small. In some cases, as shown in FIG. 5, the developing unit 11 slides down below the normal horizontal state by the difference between the diameter of the pivot 19 and the diameter of the through holes 11e and 11f of the developing unit 11. It is conceivable that the developing unit 11 may be held in a state in which the upper surfaces of the through holes 11 e and 11 f are in one-side contact with the upper surface of the pivot shaft 19. In FIG. 5, reference numerals in parentheses indicate, for convenience, members arranged on the rear side (the back side of the drawing in FIG. 1) of the image forming apparatus 1 in correspondence with members arranged on the front side. .

Therefore, in the image forming apparatus 1 of this example, the developing unit 11 and the Y-direction positioning units 11x and 11y are further moved to the photosensitive unit X and the Y-direction positioning units 5x and 5y, respectively. To be able to contact at the same time. That is,
As shown in FIGS. 2 and 5, a pair of first swing link levers 33 and 34 are provided between the front frame 11a of the developing unit 11 and the front frame 12a of the holding unit 12 and outside the rear frame 12b of the holding unit 12, respectively. , And one end thereof is connected and fixed to a swing fulcrum shaft 19 so as to be rotatable integrally with the swing fulcrum shaft 19.
One end portions of second swing link levers 35 and 36 are connected to the other end portions of the first swing link levers 33 and 34, respectively, so as to be relatively rotatable. One ends of swing lock levers 37, 38 are connected to the other ends of 35, 36, respectively, so as to be relatively rotatable. The swing lock levers 37 and 38 are formed in the same shape as each other, and the front and rear frames 1 of the swing unit 12 are
The swing fulcrum pins 39, 40 provided in 2a, 12b with their relative positions to the swing fulcrum shaft 19 being held with high precision,
Each is held swingably without backlash. That is, the swing fulcrums of the swing lock levers 37 and 38 are positioned with high precision with respect to the swing fulcrum shaft 19. The first and second swing link levers 33, 34; 35, 36 are interlocked with the rotation of the swing fulcrum shaft 19, and the respective swing lock levers 37, 38 are centered on the swing fulcrum pins 39, 40. And swing and rotate.

The other end portions of the swing lock levers 37 and 38 are engaged with positioning pins 41 and 42 of a second positioning portion, which will be described later, so that the developing unit 11 is brought into a proper position. The guide surfaces 37b, 38 for guiding the developing unit normal position setting portions 37a, 38a and the positioning pins 41, 42 of the arcuate concave portions set and held in the developing unit normal position setting portions 37a, 38a.
b is formed. Developing unit regular position setting unit 37
Both a and 38a are positioned with high precision with respect to their pivot points.

The front and rear frames 11a of the developing unit 11
11b is provided with positioning pins 41, 42 whose relative positions to the developing unit X and Y direction positioning portions 11x, 11y, which are the first positioning portions, are held with high precision. These positioning pins 41 and 42 constitute a second positioning portion provided in the developing unit 11 for positioning the developing unit 11 and the photoconductor unit 5 with high accuracy. In a state where the swing lock levers 37 and 38 are engaged with the positioning pins 41 and 42 to hold the developing unit 11 at the regular horizontal position, the swing lock levers 37 and 3
Numeral 8 is such that the developing unit 11 is hardly pressed against the photoreceptor unit 5.

As shown in FIG. 6, an operating lever 43 is provided on the front frame 12a of the holding
4 rotatably supported. The rotation fulcrum pin 44 is fitted to the operation lever 43 and can rotate integrally with the operation lever 43. The rotation fulcrum pin 44
Is fitted with an operation drive gear 45, and this rotation fulcrum pin 4
The swing fulcrum shaft 19 is provided with a swing fulcrum shaft driving gear 46 so as to be rotatable integrally with the swing fulcrum shaft 19. I have. These two drive gears 45 are connected to the front frame 2.
a through an intermediate gear 47 rotatably supported. Thus, when the operation lever 43 is rotated, the rotation of the operation lever 43 is transmitted to the swing fulcrum shaft 19 via the rotation fulcrum pin 44, the operation drive gear 45, the intermediate gear 47, and the swing fulcrum shaft drive gear 46. And the swing fulcrum shaft 19 rotates. Accordingly, the rotation of the operation lever 43 causes the pivot shaft 19 to rotate, and furthermore, the first and second pivot link levers 33, 34;
38 pivotally rotates about pivot pins 39 and 40.

Further, a cam 48 is located on the rotation fulcrum pin 44 on the front frame 12a side of the operation drive gear 45 so as to be able to rotate integrally with the rotation fulcrum pin 44, that is, to be able to rotate integrally with the rotation of the operation lever 43. Is provided. The cam 48 has a convex control surface 48 a for controlling the cam control pin 50, which will be described later, by the rotation of the operation lever 43 to control the swing of the developing unit 11, and the developing unit 1.
And a lock portion 48b formed of an arcuate concave portion for holding the first member 1 in a retracted position separated from the photoconductor unit 5. A developing unit swing drive lever 49 is provided between the swing support shaft 19 and the positioning pin 41 so as to be rotatable relative to the swing support shaft 19 and the positioning pin 41. This developing unit swing drive lever 4
9 includes a cam control pin 50 controlled by the cam 48.
Is provided.

Therefore, when the operating lever 43 is rotated, the rotation of the operating lever 43 causes the developing unit swing drive lever 49 to swing through the swing control surface 48 a of the cam 48 and the cam control pin 50. The developing unit 11 swings about the swing fulcrum shaft 19 relative to the swing fulcrum shaft 19 around the swing fulcrum shaft 19. I have. When the cam control pin 50 is fitted into the lock portion 48b of the cam 48 as shown in FIG. 7, the developing unit swing drive lever 49 is locked, and the developing unit 11 is sufficiently separated from the photoreceptor unit 5. Developing rollers 7a, 8a, 9a,
10a is held at a retracted position where it does not interfere with the photoconductor 3.

Further, as shown in FIG.
The developing unit 1 is operated by rotating the operation lever 43.
When the first and second swing link levers 3 are pivoted in the direction in which the first and second
3, 34; 35, 36 rotate in conjunction with the rotation of the operation lever 43, but as described later, the swing lock levers 37, 3
8 engages with the positioning pins 41 and 42 to hold the developing unit 11 at the proper horizontal position, and then the operation lever 43 is further rotated to swing lock levers 37 and 38.
When the developing unit 11 is pressed against the photoreceptor unit 5 with a predetermined pressing force via the positioning pins 41 and 42, the second swing link levers 35 and 36 come into contact with each other, and the second swing link levers 35 and 36 are further moved. Stopper 51 for preventing rotation of
52 are provided.

The position where the stopper 51 is provided is shown in FIG.
As shown in FIG.
In the state where the developing unit 11 is held in the regular horizontal position by engaging with the first swinging lever 1, the straight line α connecting the connecting point 54 between the second swinging link lever 35 and the swinging lock lever 37 and the swinging fulcrum shaft 19 is used. The position of the connection point 53 of the first and second swing link levers 33 and 35 located on the left side (shown by a two-dot chain line in FIG. 10) exceeds the straight line α as shown by the solid line in FIG. And the angle θ ₁ formed by the straight line β connecting the connecting point 53 and the swing fulcrum shaft 19 with the straight line α is smaller than the angle θ ₂ formed by the straight line β and the straight line α. The link lever 35 is set so as to contact the stopper 51.

Thus, when the second swing link lever 35 comes into contact with the stopper 51, the second swing link lever 3
Further, the rotation of the first swing link lever 33, the rotation of the swing lock lever 37, and the rotation of the operation lever 43 are also prevented. Moreover, in this state, the first and second swing link levers 33 and 35 are pressed against each other by a toggle action, and the developing unit 11 is pressed with a large pressing force via the swing lock lever 37. The developing unit 11 is pressed against the photoconductor unit 5 with a large holding force and is held in a state pressed against the photoconductor unit 5. Then, at least the developing unit 11
The direction of the resultant force F of the self-weight and the pressing force is set according to the position G of the center of gravity of the developing unit 11 so that the developing unit 11 does not rotate relative to the photoconductor unit 5. Thus, the first and second swing link levers 33,
The toggle means of the present invention is constituted by 35 and the stopper 51, and the pressing lever of the present invention is constituted by the swing lock lever 37.

Further, when the connecting point 53 moves from the left side to the right side beyond the straight line α, the toggle action of the first and second swing link levers 33 and 35 reversely changes, so that a click feeling is generated. By knowing the click feeling via the operation lever 43, it can be understood that the developing unit 11 has been set in a state where the developing unit 11 is pressed against the photoconductor unit 5 with a predetermined pressing force. A stopper 52 is also provided on the rear side of the holding unit 12 so that the second swing link lever 36 abuts in the same manner as the stopper 51. The stopper 52 and the first and second swing link levers 34 are provided. , 36
Constitutes the toggle means of the present invention, and the swing lock lever 37 constitutes the pressing lever of the present invention.

Next, in the thus formed image forming apparatus 1 of this example, the operation of pulling out and inserting the holding unit 12 into the main body 2 and the operation of contacting and separating the developing unit 11 from the photosensitive unit 5 explain. The description of these operations starts with the withdrawal operation of the holding unit 12 from the main body 2 at the retracted position of the developing unit 11 shown in FIG. At the retracted position of the developing unit 11, the developing rollers 7a, 8a, 9a, and 10a are
It is located 10 minutes away from The operation lever 43 is set in the vertical direction, the cam control pin 50 is fitted in the lock portion 48b of the cam 48, and the developing unit 11 is locked in the retracted position. The developing unit normal position setting portions 37a, 38a of the swing lock levers 37, 38 and the guide surfaces 37b, 38
b is the positioning pins 41, 4 of the developing unit 11
It is far away from 2. In this state, the holding unit 1
2 is pulled in front of the main body 2, and the holding unit side rail 22
Extend with respect to the intermediate rail 24 and the intermediate rail 2
4 extend with respect to the main body side rail 23, and when these two rails 22, 24 extend to the maximum extent, the holding unit 12
Is set to a predetermined withdrawal position where it is maximally withdrawn from the main body 2.

At the pulled-out position of the holding unit 12, for example, the toner cartridges 7b, 8 of the developing units 7, 8, 9, 10
When the holding unit 12 is pushed into the main body 2, the holding unit side rail 22 enters the intermediate rail 24, and the intermediate rail 24
Enters the main body side rail 23, and the ends of the rails 22, 24 abut against the corresponding stoppers 32, 32 to enter the respective rails 24, 23 to the maximum extent. It is set to the mounting position. When the holding unit 12 is pulled out and inserted, the relative position of the developing unit 11 in the X and Y directions with respect to the photosensitive unit 5 does not change, and the developing unit 11 and the photosensitive unit 5 are in the state shown in FIG. It has become.

When the operating lever 43 is rotated clockwise in FIG. 7 after the holding unit 12 is set to the mounting position of the main body 2, the cam 48 rotates in the same direction, and the cam control pin 50 is moved from the lock portion 48b. Escape and swing control surface 48
It is gradually moved downward by being guided by a. Then, the developing unit 11 can swing counterclockwise around the swing fulcrum shaft 19 by its own weight. As the operation lever 43 rotates clockwise, the developing unit 11 swings counterclockwise. The developing unit swing drive rod 49 also integrally rotates counterclockwise about the swing fulcrum shaft 19.

On the other hand, simultaneously with the clockwise rotation of the operation lever 43, the swing fulcrum shaft 19 rotates clockwise in FIG. 7 via the operation drive gear 45, the intermediate gear 47 and the swing fulcrum shaft drive gear 46. The clockwise rotation of the pivot shaft 19 causes the first swing link levers 33 and 34 and the second
The swing lock levers 37, 38 rotate counterclockwise in FIG. 5 around the swing fulcrum pins 39, 40 via the swing link levers 35, 36. At this time, the first swing link levers 33, 34 rotate in the same direction as the swing fulcrum shaft 19, and the second swing link levers 35, 36 center on the connection point with the swing lock levers 37, 38. 5, it revolves in the counterclockwise direction and revolves in the counterclockwise direction about the swing fulcrum pins 39 and 40.

The rotation of the operation lever 43 causes the developing unit 11 to swing counterclockwise, thereby causing the developing unit 11 to rotate.
The developing unit X-direction positioning portion 11x and the developing unit Y-direction positioning portion 11y of the photoconductor unit 5 of the photoconductor unit 5 are simultaneously or almost simultaneously formed by the difference in diameter between the swing fulcrum shaft 19 and the through holes 11e and 11f. It contacts the unit X direction positioning section 5x and the photoconductor unit Y direction positioning section 5y. As a result, the developing unit 11 is directly positioned with respect to the photoconductor unit 5 in the X direction and the Y direction.

In this way, the developing unit 11 is positioned directly on the photoconductor unit 5 without the intervention of the main body 2, and the photoconductor unit 5 is positioned on the main body 2 with high accuracy. And the Y-direction positioning portions 5x and 5y are both highly accurately positioned with respect to the OPC 3, the holding unit 12 is accurately positioned with respect to the main body 2, and the developing unit 11 is further improved.
11x and 11y are accurately positioned with respect to the pivot shaft 19, so that the developing unit 11 and the photoreceptor unit 5 can be accurately positioned in the X and Y directions. In this state, the guide surfaces 37b, 38 of the swing lock levers 37, 38 as shown in FIG.
b is in contact with the positioning pins 41 and 42.
In this state, even if the operation lever 43 is further rotated clockwise and the cam 48 is further rotated clockwise,
The cam control pin 50 is not controlled by the swing control surface 48a of the cam 48 at all.

By the way, even if the developing unit 11 is positioned in the X direction and the Y direction with respect to the photoreceptor unit 5 as described above, there is a gap between the swing fulcrum shaft 19 and the through holes 11e and 11f. As shown in FIG.
There is a possibility that the developing unit 11 is slightly depressed when the oblique upper right surface of 1f hits the oblique upper right surface of the swing fulcrum shaft 19. Therefore, when the operation lever 43 is further rotated clockwise to set the horizontal direction shown in FIG. 6, the swing lock levers 37, 38 are further rotated counterclockwise, so that the positioning pins 41, 42 are respectively set on the guide surfaces. It is slightly lifted by 37b and 38b and fits into the developing unit normal position setting portions 37a and 38a as shown in FIG. As a result, the developing unit 11 is pressed by the swing lock levers 37 and 38 and is firmly locked,
It is set and held at the regular horizontal position. Further, the developing unit X-direction positioning unit 11x and the developing unit Y-direction positioning unit 11y abut on the photoconductor unit X-direction positioning unit 5x and the photoconductor unit Y-direction positioning unit 5y, respectively. X
And the positioning in the Y direction is performed.

When the operation lever 43 is further rotated clockwise, the first swing link lever 33 is rotated clockwise in FIG. 9 and the second swing link lever 3 is rotated.
5 and 36 rotate counterclockwise around the connection point with the swing lock levers 37 and 38, respectively, and the connection point 53 becomes a straight line α.
And the connecting point 53 moves rightward beyond the straight line α as shown in FIG.
5, 36 abut against the stoppers 51, 52, and further rotation of the second swing link levers 35, 36 is prevented. In this state, the first and second swing link levers 33, 34;
The swing lock levers 37 and 38 press the developing unit 11 against the photoreceptor unit 5 with a large pressing force due to the thrust between the 35 and 36 due to the toggle action. In addition,
The rotation of the operation lever 43 also causes the cam 48 to further rotate clockwise. At this time, since the swing control surface 48a of the cam 48 does not control the cam control pin 50 at all, the developing unit 11 is not affected by the rotation of the cam 48.

In this manner, the swing fulcrum pins 39, 40
Are provided on the holding unit 12 so as to be positioned with high precision with respect to the pivot 19, and the positioning pins 4
Reference numerals 1 and 42 denote a developing unit X and a Y-direction positioning unit 11.
As shown in FIG. 10, the developing unit 11 is held at a regular horizontal position with high precision, so that the main body 2 is positioned with respect to the photoconductor unit 5. X direction and Y directly without going through
In any of the directions, the positioning can be performed with even higher precision.

Since the developing unit 11 is pressed against the photoreceptor unit 5 with a predetermined pressing force, each developing unit 7,
When the developing rollers 7a, 8a, 9a, and 10a of 8, 9, and 10 respectively come into contact with the OPC 3 during development, even if the developing unit 11 tries to separate from the photosensitive unit 5 due to the reaction force, the developing unit 11 There is no separation from the body unit 5.

The developing unit 11 shown in FIG. 10 is positioned at the proper position in the X and Y directions with respect to the photosensitive unit 5, and the developing unit 11 is pressed against the photosensitive unit 5 with a predetermined pressing force. To pull out the holding unit 12 from the main body 2 to replace the toner cartridges 7b, 8b, 9b, 10b, etc., first,
3 is rotated counterclockwise in FIG. Then
Since the swing fulcrum shaft 19 rotates in the same direction via the gears 45, 47, 46, the first swing link lever 33 rotates counterclockwise, and the connection point 53 moves to the left of the straight line α. When the operation lever 43 is further rotated in the same direction, the first and second swing link levers 33, 34;
The swing lock levers 37 and 38 shown in FIG.
Is at a position where the photoreceptor unit 5 is hardly pressed (at this time, the developing unit 11 is held at a regular horizontal position in a state of being positioned in the X and Y directions with respect to the photoreceptor unit 5).

When the operation lever 43 is further rotated in the same direction, the swing lock levers 37 and 38 rotate clockwise, and the developing unit normal position setting portions 37a and 38a are disengaged from the positioning pins 41 and 42, respectively. At this time, the cam 43 also rotates counterclockwise integrally with the operation lever 43, but the swing control surface 48 a of the cam 48 does not control the cam control pin 50, so that the developing unit 11 is not affected by the rotation of the cam 48. .

When the operation lever 43 is further rotated in the counterclockwise direction, the swing control surface 48a of the cam 48 controls the cam control pin 50, and the cam control pin 50 moves upward, so that the developing unit The swing drive lever 49 rotates clockwise around the swing fulcrum shaft 19. Then, the developing unit 11 is similarly rotated clockwise around the swing fulcrum shaft 19 and moves from the contact position with the photosensitive unit 5, so that the developing unit X direction positioning portion 11x and the developing unit Y direction Each of the positioning portions 11y is a photoconductor unit X-direction positioning portion 5x of the photoconductor unit 5.
And it is separated from the photoconductor unit Y-direction positioning portion 5y. Further, the swing lock levers 37, 38 are further rotated clockwise, and the developing unit regular position setting units 37a, 38
a largely deviates from the positioning pins 41 and 42, respectively.

When the operation lever 43 is rotated in the vertical direction shown in FIG. 7, the cam control pin 50 is engaged with the lock portion 48b of the cam 48, and the developing unit 11 is set and held at the retracted position. At this time, when the cam control pin 50 moves from the swing control surface 48a of the cam 48 to the lock portion 48b, a click motion occurs in the operation of the operation lever 43.
The click feeling of the operation lever 43 at this time indicates that the developing unit 11 has been set and held at the retracted position.
Thereafter, the holding unit 12 is pulled out of the main body 2 as described above. In this manner, the operation of pulling out and inserting the holding unit 11 into the main body 2 and the operation of contacting and separating the developing unit 11 from the photoconductor unit 5 are performed.

Next, an image forming operation of the image forming apparatus 1 of this example will be described. Normally, the holding unit 12 is held at a mounting position in the main body 2, and the developing unit 11 is held at a contact position where the developing unit 11 contacts the photoconductor unit 5. When the image forming apparatus 1 is not forming an image, the developing rollers 7a, 8a, 9a, and 10a are set to be separated from the OPC 3. When an image forming operation is performed in this state, the OPC 3 is turned off as shown in FIG. Rotates counterclockwise at
After C3 is charged by the charging roller, an image to be formed by the LSU 6 is exposed on the surface of the OPC 3, and OP
A latent image of this image is formed on the surface of C3. Next, the yellow developing device 7 is operated, and the yellow developing roller 7a is operated.
Is set to a development position by abutting or approaching the OPC 3 to develop a yellow image on the latent image on the OPC 3 to form a yellow toner image. Next, the yellow toner image is intermediate-transferred to the intermediate transfer body 13, and the residual toner on the OPC 3 after the intermediate transfer is removed by the photoconductor cleaner 4 and stored.

Next, after the OPC 3 is neutralized, the OPC 3 is charged and exposed again in the same manner as described above, and a latent image of an image to be formed is formed on the OPC 3. Next, the magenta developing device 8 is driven, magenta development is performed in the same manner as in the case of yellow, a magenta toner image is formed on the OPC 3, and this toner image is intermediately transferred to the intermediate transfer body 13. . Thereafter, development of cyan and black is sequentially performed in the same manner, and these cyan and black toner images are sequentially intermediate-transferred from the OPC 3 to the intermediate transfer body 13 and color-matched. In the transfer unit 14, the toner image color-matched by the intermediate transfer body 13 is taken out from the paper feed cassette 16 or the manual paper feed tray 17 by the paper feed rollers 52 and 53 and is conveyed under the control of the gate roller 54. The image is transferred to a transfer paper (not shown). Thereafter, the toner image on the transfer paper is fixed by the fixing device 15 and is conveyed to and stored in the paper discharge tray 18. Thus, a full-color image is formed by the image forming apparatus 1 of this example.

As described above, according to the image forming apparatus 1 of this embodiment, since the developing unit 11 is directly positioned on the photosensitive unit 5 without passing through the main body 2, the developing unit 11 and the photosensitive unit 5 Can be accurately positioned in the X and Y directions. In that case, the developing roller 7
a, 8a, 9a, 10a at the non-development position
The separation distance between the photoconductor 3 and the photoconductor 3 is set to a minimum necessary distance, and the developing rollers 7a, 8a, 9a, and 10a are pulled out of the main body 2 of the development unit 11 when the photoconductor 3 is pulled out.
Even if the developing unit 11 can be pulled out of the main body 2 without sufficiently retracting from the main body 2 without interfering with the photoconductor 3, highly accurate positioning between the developing unit 11 and the photoconductor unit 5 can be performed more quickly. Thus, the image forming apparatus 1 of this example can sufficiently cope with high-speed image formation.

When the developing unit 11 comes into contact with the photosensitive unit 12 and is positioned with respect to the photosensitive unit 12, the developing unit 11 is pressed by the swing lock levers 37, 38. Since the toner is pressed by the unit 12, each developing roller 7a,
Even when a reaction force is received when the photoconductors 8a, 9a, and 10a come into contact with the photoconductor 3, respectively, the developing unit 11 does not separate from the photoconductor unit 5, and the contact is stable regardless of the magnitude of the reaction force. It will be possible to maintain the state.

In this case, the developing unit 11 is pressed and held by the photosensitive unit 12 by the pressing force of the toggle means including the first and second swing link levers 33, 34; 35, 36 and the stoppers 51, 52. , A large holding force can be obtained. Further, when the developing unit 11 is pressed against the photoreceptor unit 12, a click action is performed by the operation of the toggle means, and the click feeling is transmitted to the operation lever 43, and the developing unit 11 is exposed to light by a predetermined pressing force. It is possible to know that the body unit 12 has been pressed.

Further, even if the positions of the developing unit X and the Y-direction positioning portions 11x and 11y vary with respect to the swing center of the developing unit 11 (that is, the centers of the through holes 11e and 11f), the swing fulcrum shafts 19 and through hole 11e, 1
Since this variation is absorbed by the difference in diameter from 1f, the developing unit X and Y direction positioning portions 11x and 11y of the developing unit 11 are changed to the photoconductor unit X and Y direction positioning portions 5x and 11x of the photoconductor unit 5. 5y at the same time. In addition, even if there is play between the swing fulcrum shaft 19 and the through holes 11e and 11f, the swing lock levers 37 and 38 accurately hold the developing unit 11 at the proper horizontal position. Thus, the positioning of the developing unit 11 and the photoreceptor unit 5 in the X and Y directions can be performed with even higher accuracy.

In the above-described example, the developing unit 11 is held by the holding unit 12 so as to be able to swing around the end on the side of the yellow developing unit 7, but as shown in FIG. The end on the side 10 can also be held by the holding unit 12 so as to be swingable about the swing fulcrum shaft 19.

[0066]

As is apparent from the above description, according to the image forming apparatus of the present invention, since the developing unit is directly positioned on the photosensitive unit without interposing the main body,
The positioning between the developing unit and the photoconductor unit can be performed with higher precision and more easily. In this case, as the image formation speeds up, the separation distance between the developing roller and the photoconductor at the non-developing position of the developing roller is set to a minimum necessary distance, and the developing roller is exposed when the developing roller is pulled out from the main body of the developing unit. Even if the developing unit can be withdrawn sufficiently from the body and the developing roller can be pulled out of the main body without causing the developing roller to interfere with the photosensitive member, highly accurate positioning between the developing unit and the photosensitive member unit can be performed more quickly. As a result, the image forming apparatus of the present invention can sufficiently cope with high-speed image formation.

When the developing unit comes into contact with the photosensitive unit and is positioned with respect to the photosensitive unit, the developing unit is pressed against the photosensitive unit by the pressing force from the pressing lever. Even if each developing roller receives a reaction force when it comes into contact with the photoconductor at the time of development, the developing unit does not separate from the photoconductor unit, and a stable contact state is obtained regardless of the magnitude of the reaction force. Be able to hold. In this case, since the developing unit is pressed and held by the photoreceptor unit by the pressing force of the toggle means, a large holding force can be obtained. Further, when the developing unit is pressed against the photoconductor unit, a click action is performed by the operation of the toggle means, so that the click feeling is transmitted to the operation member, and the developing unit is pressed against the photoconductor unit with a predetermined pressing force. You will be able to know what was done.

[Brief description of the drawings]

FIG. 1 is a diagram schematically illustrating an entire full-color image forming apparatus to which an embodiment of an image forming apparatus according to the present invention is applied.

FIG. 2 is a sectional view taken along the line II-II in FIG.

FIG. 3 illustrates a photoconductor unit of the image forming apparatus illustrated in FIG.
FIG. 3 is a diagram illustrating a part of a developing unit and a holding unit in a partially enlarged manner.

4A and 4B show rails for pulling out and inserting the holding unit, FIG. 4A is a diagram showing a state in which the rail is pulled out to the maximum, and FIG. 4B is a cross-sectional view in a state where the rail is reduced.

FIG. 5 is a diagram illustrating an operation lock lever and a second positioning portion.

FIG. 6 is a diagram showing a configuration for rotationally swinging a developing unit and an operation lock lever by an operation lever.

FIG. 7 is a diagram illustrating a state in which the developing unit is set to a retract position.

FIG. 8 shows a state in which the developing unit comes into contact with the photoconductor unit;
FIG. 9 is a diagram illustrating a state in which the developing unit has slipped off from a normal position.

FIG. 9 shows the developing unit in a normal position in the X direction and Y direction.
It is a figure showing the state where it was positioned in the direction.

FIG. 10 is a diagram illustrating a state in which the developing unit is pressed against and contacts the photoconductor unit.

FIG. 11 is a diagram illustrating another example of the swing of the developing unit.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Image forming apparatus, 2 ... Main body, 3 ... Photoconductor (OPC),
5 photoconductor unit, 6 LSU, 7 yellow developing device, 7a yellow developing roller, 8 magenta developing device, 8a magenta developing roller, 9 cyan developing device, 9a cyan developing Roller, 10: black developing device, 10a: black developing roller, 11: developing unit, 12: holding unit, 19: swing fulcrum shaft, 20, 2
DESCRIPTION OF SYMBOLS 1 ... Guide rail, 22 ... Holding unit side rail, 23
... Main body side rail, 24 ... Intermediate rail, 33,34 ... First
Swing link levers, 35, 36: second swing link levers, 37, 38: swing lock levers, 37a, 38a: developing unit regular position setting section, 37b, 38b: guide surfaces, 39, 40: swing fulcrum Pins, 41, 42: Positioning pins, 43: Operation lever, 45: Operation drive gear, 46: Swing fulcrum shaft drive gear, 47: Intermediate gear, 48: Cam, 48
a: swing control surface, 48b: lock portion, 49: developing unit swing drive lever, 50: cam control pins, 51, 52 ...
Stopper, 53, 54 ... connection point

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 2H030 AA07 AD01 BB02 BB24 BB33 BB71 2H035 CA07 CB01 CD11 CD14 2H071 AA13 AA38 AA39 BA04 BA13 BA14 BA15 BA16 BA19 BA22 BA36 DA08 DA15 EA04 EA06 2H077 BA07 BA08 BA09 GA13

Claims (2)

[Claims] 1. A holding unit provided on a main body so as to be capable of being pulled out and inserted in a front-rear direction of the main body between a mounting position positioned and mounted inside the main body and a pulling position pulled out of the main body, and the main body. A photoreceptor unit positioned and attached to the photoreceptor unit for holding the photoreceptor; and a photoreceptor unit that is positioned on the holding unit and is swingably provided and is swung by an operating member to contact the photoreceptor unit. A developing unit that is positioned with respect to the unit and further holds a predetermined number of developing units. Further, the developing unit is attached to the photoconductor unit in a state where the developing unit is in contact with the photoconductor unit. An image forming apparatus comprising: a developing unit pressing unit that presses with a pressing force. 2. The developing unit pressing means is swingably provided on the holding unit, and presses the developing unit against the photoreceptor unit; and operates the operating member to operate the pressing lever. 2. The image forming apparatus according to claim 1, further comprising: a toggle means for applying a pressing force to the image forming apparatus.