JPH02199470A - Image forming device - Google Patents

Abstract

PURPOSE:To reduce oscillation transmitted from the upper main body of the image forming device to an image forming part and to make relative position between the image forming part and a transfer accurate by fixing the projecting, the engaging part of the image forming part with the aid of the supporting part and the locking levers of the lower main body. CONSTITUTION:The image forming part 20 is mounted by inserting a bearing 35 which supports an image carrier 24 and a supporting shaft 37 which projects from both sides of a toner container 30 along the guide grooves 36 and 38 of a basket 19, respectively. At this time, the bearing 35 and the projecting and engaging part 51 formed on an image carrier unit 21 are supported on the upper slopes 50 and 53 of the engaging levers 45 and 47, respectively. By depressing the depressing part 55 of a knob 54 formed on the unit 21, the levers 45 and 47 turn against a spring 48 and the bearing 35 and the projecting part 51 are moved downward. Besides, the levers 45 and 47 returned by the returning force of the spring 48 press down the bearing 53 and the projecting part 51 against the supporting parts 40 and 42 on a lower slopes 49 and 52.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to an image forming apparatus that forms an image on an image carrier based on electrophotography.

2. Description of the Related Art Conventionally, an image carrier in an image forming apparatus is detachably supported for jam removal, maintenance, replacement of the image carrier, or the like. As for this supporting method, first, the upper body is attached to the lower body on which the paper conveyance path and the transfer section are attached, and the image carrier is attached to the upper body so that it can be removed toward the front side along the axial direction of the upper body. There is a way to install it. Second, a support section is provided to removably support the image carrier unit having the image carrier together with the developing unit in the lower body of the upper opening in which the paper conveyance path and the transfer section are built, and the suppressing member provided in the upper body There is a method in which the image carrier unit and the developing unit are elastically pressed downward.

Problems to be Solved by the Invention In general, a lower body has a large number of parts to be mounted, and the total weight of the parts to be mounted is also large, which requires the lower body to be rigid. Since it is placed on a desk, there is less vibration, but on the other hand, there are fewer parts attached to the upper body, and the weight of the parts is also small.Furthermore, the upper body is lightweight because it can be opened and closed. Therefore, the upper body is more likely to vibrate than the lower body. In the first method described above, the image carrier is pulled out in the axial direction, so a large work space is required for attachment and detachment.Also, since the image carrier is supported in a cantilevered state, there is concern about the supporting state after long-term use. be. Furthermore, a lock lever is provided on the front side to fix the axial movement of the image carrier, but due to variations in the mounting position of the lock lever and the length of the image carrier, It is not possible to fix even the smallest movements of

For this purpose, there is a means to press the other end of the image carrier with a suppressing member facing the lock lever, or if the suppressing horn of this suppressing member is small, the effect will be small, and if the pressing force is strong, the lock lever will not rotate. The operation requires a lot of effort and the pressing member itself becomes fatigued quickly. Furthermore, the vibration of the two-part main body is easily transmitted to the image carrier through the pressing member. Furthermore, since the image carrier is held in the upper main body and the transfer part etc. are held in the lower main body, the image carrier and the transfer part require relative positional accuracy due to variations in the relative positions of the upper main body and the lower main body. There is a risk that the cap may change. In the second method, vibrations of the upper main body are transmitted to the image carrier unit and the developing unit via the suppressing member, which greatly affects image formation.

Means for Solving the Problem An image carrier unit has an image carrier, the upper body is openably and closably connected to the upper part of the lower body in which a paper conveyance path and a transfer section disposed in the paper conveyance path are built-in. A plurality of locking protrusions are provided on both sides of the image forming section consisting of the and the developing unit,
Support parts are formed on both sides of the lower body to abut from below on a part of the image forming section including the locking protrusion; A lock lever having an upward slope bent in the opposite direction is provided on the lower body so as to be biased in one direction and rotatable.

Function When attaching the image forming section to the lower body, the locking protrusion is once supported by the upward slope of the lock lever, and when the image forming section is pushed down, the locking protrusion and the downward slope come into contact. The lock lever is retracted by force, the locking protrusion is lowered to the downward slope side, and the locking protrusion is pressed by the downward slope to fix the image forming section to the support part of the lower body where vibrations are difficult to be transmitted. As a result, there is no need for a pressing member to press the image forming section on the two-part main body, and it is therefore possible to reduce vibrations transmitted from the upper main body to the image forming section. When the image forming section is opened and the image forming section is pulled up, the lock lever is retracted by the component force based on the contact between the locking protrusion and the downward slope, and the locking protrusion is raised above the upward slope. The image forming section can be released from the lock lever, thus eliminating the need to manually operate the lock lever and improving operability.Furthermore, the image forming section and the transfer section can be integrated into a common lower body. By attaching it to the image carrier, it is possible to accurately determine the relative position of the two, and furthermore, the image forming section can be attached and detached from above the lower body, which is perpendicular to the axial direction of the image carrier, reducing the work space. be able to.

Example An embodiment of the present invention will be described based on the drawings.

FIG. 2 is a longitudinal side view showing the overall structure. In the figure, 1 is a lower body that constitutes a part of the main body of the electrophotographic printer. This lower body 1 connects a base cover 2 and an upper cover 3. One end of a top cover 4 serving as an upper body is provided in the second part of the lower body (2) so that it can be moved up and down. A power source 5 and a circuit board 6 are attached to the base cover 2. The upper cover 3 is provided with a paper transport path 8 for transporting the paper in the paper feed cassette 7, and at the end of this paper transport path 8, the paper is transported to a paper ejection tray 9 formed on the top surface of the top cover 4. A discharge path 10 for discharging paper toward
is connected to this connection, and the paper ejection path is connected to paper ejection path 1.
A switching section 11 is provided for switching between the lower main body 1 and the side surface of the lower main body 1, which is the extended surface of the paper conveyance path 8. Also,
The paper transport path 8 includes a paper feed roller 12 that contacts the top layer of paper in the paper feed cassette 7, a start sensor 13 that optically detects the paper being transported, and a detection signal from the start sensor 13. A registration roller 14 whose rotational movement is controlled, a transfer unit 15 that transfers a developed image on an image carrier 24 to a sheet of paper, which will be described later, a peeling unit 16 that peels the paper from the image carrier 24, and a high-voltage power source 17. Fixing sections 18 that clamp the paper that has passed through the transfer section 15 and fix the transferred image on the paper are sequentially arranged from upstream to downstream.

Further, a basket 19 with vertical openings located above the paper transport path 8 is attached to the upper cover 3, and an image forming unit 2 is detachably housed in the basket 19.
0 consists of an image carrier unit 21 and a developing unit 22. The image carrier unit 21 includes an image carrier 24 rotatably mounted on both sides of a support 23, and a charging section 25 that charges the image carrier 24, and a charging section 25 that charges the image carrier 24 and exposes the image carrier 24 to its outer periphery. a static eliminator 26 that makes the charge uniform, and a waste toner container 2.
7 is attached to the support body 23, and a blade 2 is attached to the waste toner container 27 to scrape off the waste toner adhering to the image carrier 24.
8 and a roller 29 that conveys the scraped off waste toner toward the back of the waste toner container 27. The developing unit 22 includes a developing roller 31 and a stirring blade 32 that stirs the toner in a toner container 3o containing toner.
(See Figure 5). Furthermore, flange-like protrusions 31a are formed at both ends of the developing roller 31 and come into contact with both outer circumferential surfaces of the image carrier 24. Further, the image carrier 24 is provided on the inner surface of the top cover 4.
An optical section 33 is attached to scan the light beam on the photosensitive surface of the photosensitive surface.

Next, the mounting structure of the basket 19 and the image forming section 20 is shown in FIGS. 1, 3, and 4. FIG. 1 is a longitudinal cross-sectional side view showing the support structure for the basket 19 and the image forming section 2°, FIG. 3 is an exploded perspective view showing the relationship between the lower main body 1 and the basket 19, and FIG. FIG. 3 is a plan view of the basket 19. As shown in these figures, a pair of handles 34 located above both ends of the image carrier 24 are integrally formed at both ends of the basket 19 . a guide groove 36 for vertically movably guiding a bearing 35 which protrudes from the side of the toner container 30 and supports the image carrier 24; and a guide groove 38 for vertically movably guiding a support shaft 37 protruding from both sides of the toner container 30. is formed. Further, the transfer portion 15 and the peeling portion 16 are positioned on a frame 39 fixed to the upper cover 3 and fixed by screws, and the frame 39 includes a support portion 40 that positions and supports the bearing 35. A fulcrum portion 41 for positioning and rotatably holding the support shaft 37 is formed, and a support portion 42 is erected to abut the lower end of the waste toner container 27 of the image carrier unit 21. . These support portions 40 and fulcrum portions 41 have a concave shape with an upper opening and a shape that expands toward the upper side.

Further, the frame 39 includes an image carrier unit 21
A locking means 43 is provided which resiliently engages. This locking means 43 includes a lock lever 45 that rotates around a support shaft 44 and a lock lever 47 that rotates around a support shaft 46.
It becomes more. The upper portions of these lock levers 45 and 47 are urged in opposite directions by the urging force of a spring 48.

The upper part of the lock lever 45 has a downward slope 49 for pressing the bearing 35 against the support part 40, and a downward slope 49 for pressing the bearing 35 against the support part 40.
The other lock lever 47 has a bottle-shaped engagement integrally formed on the outer surface of the support 23 of the image carrier unit 21. A downward slope 52 that presses the stop protrusion 51 and an upward slope 53 that bends in the opposite direction from the upper end of the downward slope 52 are formed.

Furthermore, a handle 54 is integrally formed on the housing of the static eliminator 26, which is a component of the image carrier unit 21, and a handle 56 is integrally formed on the outer side of the toner container 30. . These handles 54 and 56 are so close to the handle 34 that when the handle 34 of the basket 19 is grasped, the fingers of the same hand can be hung thereon. These handles 54 and 56 also have upward pressing parts 55 and 5.
7 and the downward finger hook for hanging the finger is part 55a.

57a are formed.

Further, on the lower surface of the housing of the optical section 33, a first
As shown in the figure, the support body 23 of the image carrier unit 21
A proximal portion 61 is formed on the upper edge of the cylindrical portion 61, which faces each other with a predetermined gap therebetween.

The fulcrum portion 41 is located closer to the image carrier 24 than the center of gravity of the developing unit 22 and above the developing roller 31 . Furthermore, the developing unit 2
2, a motor 58 for driving the developing roller 31 and the stirring blade 32 is fixed, and a power input terminal 59 connected to the motor 58 is provided to protrude downward. A knife-shaped connector 60 for elastically holding the frame 39 is fixed to the inner surface of the frame 39. This connector 60 is connected to a power source. The motor 58 is positioned in a direction away from the image carrier 24 with respect to the fulcrum portion 41 .

Furthermore, as shown in FIG. 5, a facing portion 62 is formed on the inner surface of the top cover 4 and faces a part of the toner container 30 with a predetermined gap S therebetween.

FIG. 6 is a partial front view showing a state in which the support shaft 37 of the developing unit 22 is fitted into the support portion 41 of the frame 39 with the frame 39 in cross section.

In such a configuration, when performing jam removal or maintenance, the top cover 4 is rotated upward to open the upper surface of the upper cover 3, and in this state, the handle 34 is grasped to move the basket 19 to the image carrier unit 21 and the upper cover 3. When it is pulled up together with the developing unit 22, the paper conveyance path 8 is opened. Alternatively, the image carrier unit 21 and the developing unit 22 can be moved independently with the basket 19 positioned inside the upper cover 3 by hooking the fingers on the finger hooks 55a and 57a of the handle 54 and 56 and pulling up. It can also be removed.

When disassembling a jam or assembling after maintenance, insert the bearing 35 of the image carrier unit 21 into the guide groove 36 of the basket 19 taken out from the upper cover 3, and insert the support shaft 37 of the developing unit 22 into the guide groove 38. Insert the basket 19, grasp the handle 34, and remove the bearing 35.
The basket 19 is housed in the upper cover 3 while fitting the supporting part 40 of the frame 39 and fitting the supporting shaft 37 to the supporting part 41. Or upper cover -
The image carrier unit 21 and the developing unit 22 are stored in the basket 19 without fitting the bearing 35 or the support shaft 37 into the guide groove 36° 38, the support portion 40, and the fulcrum portion 41 of the basket 19 stored in the basket 3. do. At this time, the bearing 35 whose movement in directions other than the vertical direction is regulated by the guide groove 36 is supported by the upward slope 50 of the lock lever 44, and the locking protrusion 51 is supported by the upward slope 53 of the lock lever 47. Although the basket 19 is supported, the pressing portion 55 of the handle 54 can be pressed with a finger that is idle while gripping the handle 34 of the basket 19. By this operation, the lock lever 45 rotates counterclockwise against the force of the spring 48 due to the force generated by the contact between the bearing 35 and the upward slope 50, and the downward movement of the bearing 35 is prevented. Allow. Similarly, the locking protrusion 51 is also supported by the upward slope 53 of the lock lever 47, and by pushing down the pressing part 55 of the handle 54, the component force generated by the contact between the locking protrusion 51 and the upward slope 53 Lock lever
47 rotates clockwise against the force of the spring 48,
The locking protrusion 51 is allowed to move downward. The lock lever 45, which has returned to its original state due to the return force of the spring 48, presses the bearing 35 against the bottom of the support portion 40 with its downward slope 49, and similarly, the lock lever 47 is locked with its downward slope 52. Pressing the protrusion 51 downward, the support body 23
The lower edges on both sides of the support portion 42 are pressed against each other.

The developing unit 22 is supported by its own weight with a support shaft 37 positioned at a fulcrum portion 41, but this fulcrum portion 41 is located above the developing roller 31 and closer to the image carrier 24 than the center of gravity of the developing unit 22. As a result, the developing unit 22 rotates clockwise about the fulcrum portion 41, and the protrusions 31a provided at both ends of the developing roller 31 come into contact with the outer periphery of the end portion of the image carrier 24. As a result, the developing unit 22 is attached to the frame 39 in a stable state with a constant gap at the intermediate portion between the image carrier 24 and the developing roller 31.

As described above, the image carrier unit 21 and the developing unit 2
2 is stably attached to a frame 39 that positions and fixes the transfer section 15 and the peeling section 16, so the relative position of the image carrier 24 with respect to the transfer section 15 and the peeling section 16 can be determined accurately.

Also, when handling jams or maintaining the basket,
9 is pulled up, but in this process, the bearing 35 presses the downward slope 49 of the lock lever 45, and the force generated by the contact between the two causes the lock lever 45 to move against the spring 4.
The locking protrusion 51 rotates counterclockwise against the force of the lock lever 8, allowing upward movement of the bearing 35.
The lock lever 47 is rotated clockwise against the horn of the spring 48 by the force generated by the contact between the two, thereby preventing the upward movement of the locking protrusion 51. Allow.

Furthermore, the developing unit 22 is exposed to extreme vibrations during transportation, etc.
can be prevented from floating by the facing portion 62 of the top cover 4. In this case, by forming the facing portion 62 with a buffer member, even if it interferes with the developing unit 22, it will not be damaged. Furthermore, by facing the developing unit 22 with a predetermined gap S between the opposing portion 62 and the developing unit 22, it is possible to prevent vibrations caused by applying an external force to the top cover 4 from being transmitted to the developing unit 22. can. The proximal portion 61 presses the support 23 when the top cover 4 is closed even if the support 23 is not fully attached, but when the support 23 is fixed in place, the proximal portion 61 presses against the support 23 when the top cover 4 is closed.
A slight gap is formed between and the support body 23. Therefore, vibrations are not transmitted from the top cover 4 to the support body 23.

The lower main body 1 has a large number of parts mounted through the frame 39, and has high rigidity because it can hold even heavy parts.Moreover, since it is placed on a stable stand or desk, there is little vibration. There is no possibility that harmful vibrations will be transmitted from the lower main body 1 to the developing unit 22 or the image carrier unit 21.

Furthermore, when attaching the image forming section 20 to the lower main body l,
The bearing 35 and the locking projection 51 are once supported by the upward slopes 50 and 53 of the lock levers 45 and 47, and when the image forming section 20 is pushed down, the bearing 35 or the locking projection 51 and the upward slope 5
Lock lever 44,, by component force based on contact with 0.53,
When the upper body 4 is opened and the image forming section 20 is pulled up together with the basket 19, the bearing 35 Alternatively, the locking levers 45 and 47 are rotated in the retracting direction by the component force based on the contact between the locking protrusion 51 and the downward slope 49,52, and the bearing 35 and the locking protrusion 51 are moved toward the upward slope 5.
0.53'', thus eliminating the need to manually operate the lock lever 45° 47 and improving operability.

Furthermore, by positioning the bearing 35 on the rotation axis of the image carrier 24 as a locking protrusion using the support portion 40 and fixing it with the lock lever 45, the axial center position of the image carrier 24 can be accurately set. can.

Moreover, the lock levers 45 and 47 are made of one spring 4.
However, by changing the distance from the respective support shafts 44 and 46 to the tip, the lock lever 45 is pushed down onto the bearing 35 by the pushing down force on the locking protrusion 51 by the lock lever 47. By increasing the force, the bearing 35 at the center of the image carrier 24 is
The support body 23 can be brought into contact with the support part 42 by rotating the support body 23 using the contact part as a fulcrum. That is, the axial center position of the image carrier 24 is always stabilized at a fixed position.

Therefore, the position of the image carrier 24 relative to the transfer section 15 can be determined even more accurately. Since this bearing 35 is fixed to the frame 39 by a lock lever 45,
Wear between the bearing 35 and the support portion 40 can be prevented.

Note that by making the support shaft 37 made of metal, wear of the support shaft 37 due to contact with the metal frame 39 can be prevented. Thereby, the developing unit 22 can be positioned with high accuracy. Of course, a method may be adopted in which the support shaft 37 is molded integrally with the toner container 30 to improve productivity. In this case, a synthetic resin chip that contacts the support shaft 37 may be attached to a part of the frame 39, or the frame 39 itself may be made of synthetic resin, and the support shaft 37 may be
7 may be prevented from wearing out. Furthermore, as shown in FIG. 7, a protrusion 37a may be formed at the end of the support shaft 37. The protrusion 37a comes into contact with the side surface of the frame 39 and acts as a guide when the support shaft 37 is fitted into the support portion 41, and also prevents the development unit 22 from swinging in the left-right direction. Even if the frame 39 is deformed and its width increases, the width of the frame 39 can be corrected by fitting the support shaft 37 to the support portion 41.

Effects of the Invention Since the present invention is configured as described above, when the image forming unit is attached to the lower main body, the locking protrusion is supported once by the upward slope of the lock lever, and when the image forming unit is pushed down, the locking protrusion is held. The lock lever is retracted by the component force based on the contact between the protrusion and the upward slope, the locking protrusion is lowered to the downward slope, and the locking protrusion is pressed by the downward slope to open the image forming section. Vibration is transmitted and DTIt
This eliminates the need for a suppressor to press the image forming section on the upper body, thereby reducing vibrations transmitted from the upper body to the image forming section. Also, when the upper body is opened and the image forming section is pulled up, the lock lever is retracted by the component force based on the contact between the locking protrusion and the downward slope, and the locking protrusion is moved upward. By raising the image forming section to one side of the slope, the image forming section can be released from the lock lever, which eliminates the need to manually operate the lock lever and improves operability. By attaching the image forming section and the transfer section to a common lower body, the relative positions of both can be determined accurately.Furthermore, the image forming section can be attached and detached from the lower body that is perpendicular to the axial direction of the image carrier. Since it is possible to
49...Downward slope, 50...Directed slope which has an effect such as being able to reduce the work space, 51...Locking protrusion, 52...Downward slope.

...upward slope

[Brief explanation of the drawing]

The drawings show one embodiment of the present invention, and FIG.
The figure is a longitudinal side view showing the overall structure, Figure 3 is an exploded perspective view showing the relationship between the lower main body and the basket, Figure 4 is a plan view of the basket housing the image forming section, and Figure 5 is a view of the developing unit. The longitudinal side view and FIGS. 6 and 7 are partial front views showing several states of the developing unit with the frame in section.

Claims (1)

[Claims] 1. An image carrier having an image carrier, the upper body being openably and closably connected to the upper part of the lower body in which a paper conveyance path and a transfer section disposed in the paper conveyance path are built-in. A plurality of locking protrusions are provided on both sides of an image forming section consisting of a unit and a developing unit, and support portions are provided on both sides of the lower main body that abut a part of the image forming section including the locking protrusions from below. The lower body is rotated by urging in one direction a lock lever having a downward slope that contacts the locking protrusion and an upward slope that bends in the opposite direction from the upper end of the downward slope. An image forming apparatus characterized in that it is provided with. 2. The image forming apparatus according to claim 1, wherein the locking protrusions are arranged at positions including the rotation axis of the image carrier.