JP2000352921A - Electrophotographic image forming device, and process cartridge - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent the sliding load of a movable contact point from increasing and to prevent an imperfect attachment of a process cartridge by bringing the contact point movable in the attaching direction of the process cartridge provided in an image forming device main body into contact with a contact point whose contact part is a plane in a direction perpendicular to an attaching/ detaching direction. SOLUTION: This process cartridge B is attached to the device main body in a direction shown by an arrow in the figure. The contact points 17a to 17c are exposed from the frame body of the process cartridge B on a front side in a process cartridge inserting direction. The contact point 17a communicates with a transfer roller 4. The contact point 17b communicates with a developing roller. Then, the contact point 17c communicates with a toner antenna. The contact points 17a to 17c have the contact surfaces 17a1 to 17c1 being the planes perpendicular to a direction where the process cartridge B is attached to the device main body. The contact surfaces 17a1 to 17c1 are brought into contact with contact pins 15a to 15c. Thus, the device is prevented from getting in an imperfect state and a jamming is not caused.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] 1. Field of the Invention [0002] The present invention relates to a process cartridge and an electrophotographic image forming apparatus. Here, the electrophotographic image forming apparatus forms an image on a recording medium using an electrophotographic image forming method. Examples of the electrophotographic image forming apparatus include, for example, an electrophotographic copying machine, an electrophotographic printer (for example, a laser beam printer, an LED printer, etc.), a facsimile machine, and a word processor.

A process cartridge is a unit in which a charging unit, a developing unit or a cleaning unit and an electrophotographic photosensitive drum are integrally formed into a cartridge, and this cartridge is detachable from an image forming apparatus main body. In addition, at least one of the charging unit, the developing unit, and the cleaning unit and the electrophotographic photosensitive drum are integrally formed into a cartridge so that the cartridge can be attached to and detached from the image forming apparatus main body. Further, at least the developing means and the electrophotographic photosensitive drum are integrally formed into a cartridge so as to be detachable from the apparatus main body.

[0003]

2. Description of the Related Art Conventionally, in an image forming apparatus using an electrophotographic image forming process, an electrophotographic photosensitive member and process means acting on the electrophotographic photosensitive drum are integrally formed into a cartridge, and this cartridge is used for image forming. A process cartridge system detachable from the apparatus main body is employed. According to this process cartridge system,
Since the maintenance of the apparatus can be performed by the user himself without relying on a service person, the operability can be remarkably improved. Therefore, this process cartridge system is widely used in image forming apparatuses.

In such a process cartridge, a process cartridge which is detachably attached to an image forming apparatus main body from a crossing direction of an electrophotographic photosensitive drum is frequently used.

FIG. 10 shows a printer as an electrophotographic image forming apparatus to which the above-mentioned process cartridge can be attached and detached. In the figure, when the open / close cover 14 is pivoted upward about the shaft 14a and opened, and the process cartridge B is mounted obliquely downward from the opening of the apparatus main body 13 as indicated by the arrow A,
As shown in FIG.
a, 17b, and 17c bias the contact pins 15a, 15b, and 15c, which are movably held in the vertical direction by the transfer block 13e, upward, and apply springs 16a and 1 for applying a voltage.
6b, 16c, contact pins 15a, 15b, 15
c is pushed into the transfer block 13e. At the same time as the contact is pushed in, the contacts 17a, 17b, and 17c correspond to the displacement of the contact pins 15a, 15b, and 15c.
Slide with 17c.

Here, the contact points 17a, 17b, 17c have contact surfaces in a substantially horizontal direction with respect to the contact pins 15a, 15b, 15c, and the contact surfaces are flat.

[0007]

However, in the above-mentioned conventional example, when a coupling or the like is used as a driving mechanism of the process cartridge, the process cartridge is urged by using a spring or the like so as not to move from a fixed position. In some cases, it is not possible to do so.In that case, when mounting the process cartridge, the contact pins for applying electric charge to the process cartridge will be pushed in,
While the contact pins are mounted so as to move up and down, the process cartridge is inserted at an angle θ with respect to the horizontal direction. Therefore, a horizontal component T1 / tan θ T1: contact point A force (= contact pressure) that pushes down the pin vertically acts, and the contact pin is strongly pressed against the guide portion, thereby increasing the sliding resistance.

[0008] As the sliding resistance increases, the force T1 for pushing down the contact pins also increases, so that the force for inserting the process cartridge also increases.

In this case, there is a possibility that the operator who inserts the process cartridge thinks that the process cartridge is mounted when the contact of the process cartridge comes into contact with the contact pin and the resistance increases, and the apparatus main body is operated in this state. If the user tries to move the process cartridge even though the process cartridge is not installed in the correct position, the main unit detects that there is no process cartridge and displays an error message. Because the main unit tries to move when the cartridge cannot be driven,
When paper as a recording medium is transported to the transfer unit,
Paper jam occurs because the process cartridge is not driven.

The invention of the present application provides an electrophotographic image forming apparatus and a process cartridge in which a sliding load of a movable contact is prevented from increasing and a process cartridge in which incomplete mounting of a process cartridge is prevented is removable. With the goal.

[0011]

The main aspects of the present invention are as described below with reference to the claims.

According to a first aspect of the present invention, there is provided a process cartridge detachable from a main body of an image forming apparatus in a direction crossing an electrophotographic photosensitive drum, and acts on the electrophotographic photosensitive drum and the electrophotographic photosensitive drum. A process unit, and a contact having a surface perpendicular to the mounting / removing direction with respect to the image forming apparatus main body as a contact portion; A process cartridge.

According to a seventh aspect of the present invention, there is provided an electrophotographic image forming apparatus in which a process cartridge is detachable from a direction crossing the electrophotographic photosensitive drum, comprising: a, an electrophotographic photosensitive drum; and the electrophotographic photosensitive drum. Mounting means for removably mounting a process cartridge having a process means acting on the contact member, and a contact having a surface perpendicular to the direction of attachment and detachment to the image forming apparatus main body; A contact member capable of being moved in the mounting direction of the process cartridge; c, an urging means for urging the contact member toward the contact point; and d, a conveying means for conveying the recording medium. Is an electrophotographic image forming apparatus.

[0014]

Embodiments of the present invention will now be described with reference to the drawings.

In the following description, the longitudinal direction is a direction perpendicular to the conveying direction of the recording medium and along the surface of the recording medium.
It matches the axial direction of the photosensitive drum.

First Embodiment First, a process cartridge B according to an embodiment and an electrophotographic image forming apparatus A to which the process cartridge B can be removably mounted will be specifically described with reference to FIGS. . Here, as an order of the description, first, the overall configuration of the process cartridge B and the electrophotographic image forming apparatus A using the process cartridge B will be described with reference to FIGS.

{Overall Configuration} FIG. 2 is a sectional explanatory view of a laser beam printer as an electrophotographic image forming apparatus A in which a process cartridge B is detachably mounted.

As shown in FIG. 2, the printer A irradiates the photosensitive drum 7 with a laser beam based on image information from the optical system 1 to form a latent image on the photosensitive drum 7. The toner image is formed by developing with toner. In synchronization with the formation of the toner image, the recording medium 2
From a, the sheet is conveyed by a conveying means 3 including a pickup roller 3b, a conveying roller pair 3d and a registration roller pair 3e. The toner image formed on the photosensitive drum 7 is transferred to the recording medium 2 by applying a voltage to a transfer roller 4 as a transfer unit.

Then, the recording medium 2 is transported by the transport belt 3f and transported to the fixing means 5. The fixing means 5 is composed of a fixing rotator 5c including a driving roller 5a and a heater 5b, and applies heat and pressure to the recording medium 2 passing therethrough to fix the transferred toner image on the recording medium 2. And recording medium 2
Is transported by the pair of discharge rollers 3g and 3h, and is discharged to the discharge unit 6 through the reverse transfer path.

The printer A can also be manually fed by a manual tray and rollers. (Description is omitted).

On the other hand, the process cartridge B has an electrophotographic photosensitive drum and at least one process means. Here, as the processing means, for example, a charging means for charging the electrophotographic photosensitive drum, a developing means for developing a latent image formed on the electrophotographic photosensitive drum, and cleaning of toner remaining on the surface of the electrophotographic photosensitive drum Cleaning means for cleaning.

As shown in FIG. 3, the process cartridge B of this embodiment has an electrophotographic photosensitive drum 7, a charging roller 8, an exposure opening 9, a developing unit 10, and a cleaning unit 11. The process cartridge B rotates the photosensitive drum 7 from the apparatus main body 13 by a shaft coupling device. Then, the surface is uniformly charged by applying a voltage to a charging roller 8 serving as a charging unit, and information light from the optical system 1 is exposed to a photosensitive drum 7 through an exposure opening 9 to form a latent image. Then, development is performed by the developing unit 10.

The developing means 10 includes a toner storage section 10a.
The toner in the inside is sent out by the toner sending member 10b, and the developing roller 10d containing the fixed magnet 10c is rotated, and a toner layer provided with a triboelectric charge by the developing blade 10e is formed on the surface of the developing roller 10d. The toner image is formed by transferring the toner image to the photosensitive drum 7 in accordance with the latent image, and is visualized. Then, a voltage having a polarity opposite to that of the toner image is applied to the transfer roller 4 provided on the apparatus main body 13 to transfer the toner image to the recording medium 2. The residual toner is removed from the photosensitive drum 7 after the transfer by the cleaning unit 11. That is,
The remaining toner is scraped off by the cleaning blade 11a. The scraped-off toner is collected by a squeeze sheet 11b in a removed toner reservoir 11c.

The charging roller 8 is in contact with the photosensitive drum 7 and is driven to rotate by the photosensitive drum 7. Also,
The cleaning blade 11a is in contact with the photosensitive drum 7.

In the process cartridge B, a toner frame 12a having a toner storage portion 10a for storing toner and a developing frame 12b for holding a developing member such as a developing roller 10d are welded (in this embodiment, an ultrasonic wave). (Welding) to form a developing unit. The cleaning unit 1 supports the developing unit with the photosensitive drum 7, the charging roller 8, the cleaning unit 11, and the like.
2c are slidably connected to each other, and are urged by a compression coil spring about the connection point to press the photosensitive drum 7 and the large-diameter portions at both ends of the developing roller 10d. The process cartridge B is removably mounted by a user on a cartridge mounting means described later provided on the apparatus main body 13 from a direction intersecting the longitudinal direction of the photosensitive drum 7. (See FIGS. 6 and 7).

The cleaning frame 12c has a structure shown in FIG.
A mounting guide 12c4 is provided near a bearing 12c2 that supports the drum shaft 36a of the photosensitive drum 7 shown in FIG. Further, a bearing 34 attached to the cleaning frame 12c to support the photosensitive drum 7 shown in FIG.
Is integrally formed with a mounting guide 12c5. The mounting guides 12c4 and 12c5 are used when the process cartridge B is mounted.
Guided by 5a, 35c.

As the cartridge mounting means, FIG.
As shown in FIG. 7, a cartridge mounting guide member 35 is attached to both right and left sides of a cartridge mounting space provided in the apparatus main body 13 so as to face each other (FIG. 6 shows one side, and FIG. 7 shows the other side). The left and right guide members 35
Are provided with guide portions 35a and 35c, which are guides for inserting the process cartridge B, facing each other. The guide portions 35a and 35c are provided diagonally forward and downward when viewed from the mounting direction of the process cartridge B. A cylindrical boss 34a (see FIG. 4 which is integral with the bearing 34) is formed on each of the guide portions 35a and 35c so as to protrude from both sides in the longitudinal direction of the cartridge frame, the bearing 12c2, and the mounting guide 12c4.
12c5 is guided and inserted. The cylindrical boss 34a is supported by a U groove 35d provided at the end of the guide portion 35c, and the bearing 12c2 is provided at the end of the guide portion 35a.
Fit into the groove 35b. Then, the boss 34a and the bearing 12
The moment when c2 fits into the U-grooves 35d and 35b and the process cartridge B is about to rotate, the regulating contact portions 12c1 provided on both longitudinal sides of the upper surface of the cleaning frame 12c are fixed to the fixed member 13a of the apparatus main body 13. Received by contacting the

In order to mount the process cartridge B on the apparatus main body 13, an openable cover 14 that can be opened and closed with respect to the apparatus main body 13 around the shaft 14a shown in FIG. 2 is opened. Then, the process cartridge B is mounted on the image forming apparatus main body 13 by closing the opening / closing cover 14. In addition, when removing the process cartridge B from the apparatus main body 13, the opening / closing cover 14 is opened.

When the process cartridge B is mounted on the image forming apparatus main body 13, the cartridge-side shaft coupling member 37 (see FIG. 4) and the apparatus main body-side shaft coupling member 39 (FIG. 7) interlock with the closing operation of the opening / closing cover 14. And the photosensitive drum 7 and the like are rotatable by being driven by the apparatus main body 13. The cartridge-side shaft coupling 37 is provided at one end of the photosensitive drum 7 in the longitudinal direction.

FIG. 1 is a drawing that best illustrates the features of the present invention. Here, the process cartridge B is mounted on the apparatus main body 13 from the direction of arrow A. The contacts 17a, 17b and 17c are exposed from the frame of the process cartridge B on the front side in the process cartridge insertion direction. The contact 17a communicates with the transfer roller 4. The contact 17b communicates with the developing roller 10d. The contact 17c communicates with a toner antenna (not shown). Each of these contacts 17a,
Reference numerals 17b and 17c denote an apparatus main body 1 of the process cartridge B.
3 are flat contact surfaces 17a1 and 17b perpendicular to the mounting direction.
1, 17c1. These contact surfaces 17a1, 17
b1 and 17c1 contact the contact pins 15a, 15b and 15c.

In FIG. 1, B is a process cartridge,
7 is a photosensitive drum, 4 is a transfer roller, 15a, 15b,
Reference numeral 15c denotes a contact pin having a hemispherical tip, which is fitted in the holes 13f, 13b, and 13c, respectively, so as to be movable in parallel to the illustrated arrow A. 16a, 16b, 16c are contact pins 15a,
A compression coil spring for urging the upper portions 15b and 15c to supply electric charges, and is made of a conductive material.
13d has the holes 13a, 13b, 13c and has a contact 15
a, 15b, and 15c show transfer blocks that hold and guide. The transfer block 13d is fixed to the apparatus main body 13. The lower ends of the compression coil springs 16a, 16b, 16c communicate with a high-voltage power supply of the apparatus main body 13 or a residual toner detection circuit.

In FIG. 1, the angle θ with respect to the horizontal direction is
Indicates the direction in which the process cartridge B is inserted.

The process cartridge B is mounted on the apparatus main body at an angle θ with respect to the horizontal direction.
15b and 15c are guided by the transfer block 13d so as to slide at the same angle as the insertion angle θ of the process cartridge B with respect to the horizontal line, and the springs 16a, 16b and 16c are also provided with contact pins 15a, 15b and 15c at an angle θ. Holes 13f, 13b, and 1 serving as guide portions of the transfer block 13d with respect to the contact pins 15a, 15b, and 15c.
Since the force pressing against the peripheral wall of 3c hardly acts, the sliding resistance of the contact pins 15a, 15b, 15c does not increase. Therefore, when the process cartridge B is mounted on the apparatus main body 13, it does not receive a particularly large reaction force at the end. The horizontal direction substantially coincides with the transport direction of the recording medium 2 at the transfer section.

[Second Embodiment] FIG. 8 shows a second embodiment, and only different points from the first embodiment will be described. Otherwise, the description of Embodiment 1 is adopted.

Reference numeral 14 denotes an opening / closing cover for replacing the process cartridge.
It can be mounted from the same direction in the vertical direction of the movable directions of a, 15b, and 15c. The opening / closing cover 14 opens the upper surface of the apparatus main body 13 greatly. The optical system 1 is attached to an opening / closing cover 14. Although not denoted by reference numerals in FIG.
The contact surfaces of b and 17c with the contact pins 15a, 15b and 15c are horizontal planes.

[Third Embodiment] FIG. 9 shows a third embodiment, and only different points from the first embodiment will be described. For the rest, the description of Embodiment 1 is cited.

20a and 20b are process cartridges B
Embodiment 1 shows a contact spring for supplying an electric charge to the first embodiment.
In this embodiment, the contact pin and the spring for applying the contact pressure are separated from each other. However, in this embodiment, the contact pin and the contact spring are integrated, the process cartridge B is inserted into the apparatus main body 13, and the contact springs 20a and 20b are connected. When contact is made, the contact spring 20
The displacement directions of a and 20b are set to be the angle θ.

According to this embodiment, the contacts 17a, 17
b and the contact springs 20a and 20b contact each other, there is almost no sliding between the contact surfaces, so that there is no contact wear, and only the reaction force of the contact spring is applied to the process cartridge B. Special operation force does not become heavy at the end of attachment to the main body.

[0039]

As described above, according to the present invention,
By making the mounting direction of the process cartridge into the image forming apparatus main body coincide with the moving direction of the movable biased contact member of the image forming apparatus main body that comes into contact with the contact of the process cartridge, the movement of the contact member becomes smooth. Since an abnormal resistance does not occur when the process cartridge is inserted, even when the user mounts the process cartridge in the image forming apparatus main body, the process cartridge is not completely mounted, and There is no erroneous detection of the presence / absence of the process cartridge due to a wrong mounting state, and no jam of the recording medium due to the fact that the drive is not transmitted to the process cartridge.

[Brief description of the drawings]

FIG. 1 is a side view partially showing a contact device of an image forming apparatus main body and a process cartridge according to a first embodiment of the present invention;

FIG. 2 is a longitudinal sectional view of the electrophotographic image forming apparatus according to the first embodiment of the present invention.

FIG. 3 is a vertical sectional view of the process cartridge.

FIG. 4 is a perspective view of a process cartridge.

FIG. 5 is a perspective view of a process cartridge.

FIG. 6 is a perspective view of a cartridge mounting portion.

FIG. 7 is a perspective view of a cartridge mounting portion.

FIG. 8 is a longitudinal sectional view of an electrophotographic image forming apparatus according to a second embodiment of the present invention.

FIG. 9 is a side view of a process cartridge according to a third embodiment of the present invention.

FIG. 10 is a longitudinal sectional view of a conventional electrophotographic image forming apparatus.

FIG. 11 is a side view showing a partial cross section of a contact device of a conventional image forming apparatus main body and a process cartridge.

[Explanation of symbols]

A: Electrophotographic image forming apparatus B: Process cartridge 1: Optical system 2: Recording medium 3: Conveying means 3a: Paper feed cassette 3b: Pickup roller 3d: Conveying roller pair 3e: Registration roller pair 3f: Conveying belt 3g: Discharge roller Pair 3h: Discharge roller pair 4: Transfer roller 5: Fixing means 5a: Drive roller 5b: Heater 5c
... Fixing rotating body 6 ... Ejecting unit 7 ... Photoreceptor drum 8 ... Charging roller 9 ... Exposure opening 10 ... Developing unit 10a ... Toner storage unit 10b ... Toner sending member 10c ... Fixed magnet 10d ... Developing roller
10e: developing blade 11: cleaning means 11a: cleaning blade 11b: squeeze sheet 11c: removed toner reservoir 12a: toner frame 12b: developing frame 12
c: cleaning frame 12c1: regulating contact part 1
2c2 Bearing 12c4 Mounting guide 12c5 Mounting guide 13 Device body 13a Fixed member 13b Hole 13
c ... Hole 13d ... Transfer block 13e ... Transfer block 13f ... Hole 14 ... Open / close cover 14a ... Shaft 15a ... Contact pin 15b ... Contact pin 15c ... Contact pin 16a ... Spring 16b ... Spring 16c ... Spring 17a ... Contact 17b ... Contact 17c ... Contact 17c Contact 17a
1, 17b1, 17c1 Contact surface 20a Contact spring 20b Contact spring 34 Bearing 34a Boss 35 Mounting guide member 35a Guide portion 35b U
Groove 35c Guide part 35d U groove 36a Drum shaft 37 Cartridge-side shaft coupling member 39 Device main body-side shaft coupling member

Claims (10)

[Claims] 1. A process cartridge detachable from an image forming apparatus main body in a direction crossing an electrophotographic photosensitive drum, comprising: an electrophotographic photosensitive drum; a process unit acting on the electrophotographic photosensitive drum; A contact having a surface in a direction perpendicular to the mounting / removing direction to the main body as a contact portion, wherein the contact comes into contact with a contact movable in a process cartridge mounting direction provided in the image forming apparatus main body. cartridge. 2. The process cartridge according to claim 1, wherein the process cartridge is mounted obliquely with respect to a conveying direction of the recording medium. 3. The process cartridge according to claim 1, wherein the process cartridge is mounted from a direction substantially perpendicular to a conveying direction of the recording medium. 4. The process cartridge according to claim 1, wherein the charging unit or the cleaning unit, the developing unit, and the electrophotographic photosensitive drum are integrally formed into a cartridge, and the cartridge is detachably mountable to an image forming apparatus main body. 4. The process cartridge according to any one of 1 to 3. 5. The process cartridge according to claim 1, wherein at least one of a charging unit, a cleaning unit, a developing unit, and an electrophotographic photosensitive drum are integrated into a cartridge to be detachable from an image forming apparatus main body. 3. The process cartridge according to any one of 3. 6. The process cartridge according to claim 1, wherein the process cartridge is configured such that a developing unit and an electrophotographic photosensitive drum are integrally formed into a cartridge so as to be detachable from a main body of the image forming apparatus. . 7. An electrophotographic image forming apparatus in which a process cartridge is detachable from a direction crossing an electrophotographic photosensitive drum, comprising: a, an electrophotographic photosensitive drum; and processing means acting on the electrophotographic photosensitive drum. Mounting means for detachably mounting a process cartridge having a contact having a surface perpendicular to the direction of attachment and detachment to the image forming apparatus main body; and b, a mounting direction of the process cartridge capable of contacting the contact. An electrophotographic image, comprising: a movable contact member; c, an urging means for urging the contact member toward the contact; and d, a conveying means for conveying the recording medium. Forming equipment. 8. The contact member according to claim 7, wherein the contact member is movable in a direction oblique to a conveying direction of the recording medium.
2. The electrophotographic image forming apparatus according to 1. 9. The recording medium according to claim 7, wherein the contact member is movable in a direction substantially perpendicular to a conveying direction of the recording medium.
2. The electrophotographic image forming apparatus according to 1. 10. An electrophotographic image forming apparatus according to claim 7, wherein said urging means also serves as a contact member.