JPH02213859A - Image forming device - Google Patents

Abstract

PURPOSE:To eliminate a member which presses an image forming part and to reduce vibration transmitted from the upper main body by pressing a part of the image forming part on a supporting part and simultaneously pinching an engaging projection part between the receiving part of locking lever and a downward slope when the image forming part is mounted on a lower main body. CONSTITUTION:When the image forming part 20 is mounted on the lower main body 1, the engaging projection part 35 is once supporting by the upward oblique surface 50 of the locking lever 45. When the image forming part 20 is depressed, the locking lever 45 is retreated by component force arising from the abutting the engaging projection part 51 on the upward oblique surface 50 in order to lower the engaging projection part 35. The part of the image forming device 20 is pressed on the supporting part 42 by depressing the downward oblique surface 49. In addition, the engaging projection part 35 is pinched between the receiving part 63 of the locking lever 45 and the downward oblique surface 49 without having play so that the image forming part 20 can be fixed on the supporting part 42 of the lower main body 1 where vibration is difficult to be transmitted. Therefore, a pressing member which presses the image forming part on the upper main body is not needed, and the vibration transmitted to the image forming part from the upper main body can be reduced.

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 few parts attached to the upper body, and the weight of the parts is small.
The upper body is lightweight in order to open and close. 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 method of holding the image carrier between a lock lever and a suppressing member at both ends in the axial direction, but if the pressing force of this pressing member is small, the effect is small, and if the pressing force is strong, the lock lever will not rotate. It takes a lot of effort to operate, and the suppressing member itself becomes fatigued quickly. Furthermore, vibrations of the upper body are easily transmitted to the image carrier via the suppressing 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 gap between In the second method, vibrations of the upper body are transmitted to the image carrier unit and the developing unit via the pressing 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,
A support part that abuts a part of the image forming section including the locking protrusion from below and a groove for vertically movably holding at least one of the locking protrusions are formed on both sides of the lower main body; A plurality of lock levers each having a downward slope abutting the locking protrusion and an upward slope bending in an opposite direction from the upper end of the downward slope are provided on the lower body so as to be biased in one direction and rotatable. , a receiving part is formed on at least one of the lock levers to support the locking protrusion and faces substantially horizontally from the lower end of the downward slope, and a pivoting center of the lock lever having the receiving part is formed. A movable fulcrum part is provided that can be held in a movable manner.

Function When attaching the image forming section to the lower main body, the locking protrusion is temporarily supported by the downward slope of the lock lever, and when the image forming section is pushed down, the locking protrusion and the upward slope come into contact with each other. The lock lever is retracted by force and the locking protrusion is lowered to the downward slope side, and the locking protrusion is pressed by the downward slope to press a part of the image forming section against the support section, and at the same time, the receiving section is By sandwiching the locking protrusion without any play between the receiving part of the lock lever and the downward slope, the image forming part can be fixed to the support part of the lower main body to which vibrations are difficult to be transmitted. This eliminates the need for a suppressing member to press the image forming section on the upper body, thereby reducing vibrations transmitted from the upper body to the image forming section. By displacing the center of motion at the movable fulcrum part, the pressing force of the lock lever against the locking protrusion can be adjusted, and the locking protrusion can be positioned in the height direction by the receiving part of the lock lever. In this case, the image forming section can be positioned in the height direction using the support section, and furthermore, when the upper body is opened and the image forming section is pulled up, the position of the image forming section can be adjusted based on the contact between the locking protrusion and the downward slope. Use force to retract the lock lever and move the locking protrusion above the upward slope.''1
By raising the image forming section, the image forming section can be released from the lock lever, thereby eliminating the need to manually operate the lock lever and improving operability. By attaching them 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 above the lower body, which is perpendicular to the axial direction of the image carrier, which saves work space. can be reduced.

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

FIG. 4 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 attached to the upper part of the lower body 1 so as to be vertically movable. 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 paper ejection path 10 for ejecting the paper toward is connected to this connecting portion, and a switching unit 11 for switching the ejection path of the paper to the side surface of the lower main body 1, which is on the extension surface of the paper ejection path 10 or the paper conveyance path 8, is connected to this connection part. It is provided. Further, the paper conveyance path 8 includes a paper feed roller 12 that contacts the uppermost sheet of the paper feed cassette 7, a start sensor 13 that optically detects the conveyed paper, and a detection sensor 13 that detects the paper that is being conveyed. A registration roller 14 whose rotational movement is controlled by a signal, a transfer section 15 that transfers a developed image on an image carrier 24 to a sheet of paper, which will be described later, a peeling section 16 that separates the paper from the image carrier 24, and a high-voltage power source 17. and a fixing section 18 that clamps the paper that has passed through the transfer section 15 and fixes the transferred image on the paper are sequentially arranged from upstream to downstream.

Further, a basket 19 with a bottom opening located above the paper transport path 8 is attached to the upper cover 3;
The image forming section 20 detachably housed in the basket 19 includes 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, 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 light on its outer periphery. A static eliminator 26 that makes the charge uniform and a waste toner container 27 are attached to the support 23, and the waste toner container 27
A blade 28 for scraping off waste toner adhering to the image carrier 24 and a roller 29 for conveying the scraped off waste toner toward the back of the waste toner container 27 are attached to the image carrier 24 .

The developing unit 22 includes a developing roller 31 and a stirring blade 3 that stirs the toner in a toner container 30 containing toner.
2 (see Figure 7). Furthermore, flange-shaped protrusions 31a are formed at both ends of the developing roller 31 to contact the outer circumferential surfaces of both ends of the image carrier 24.

Further, the image carrier 2 is provided on the inner surface of the top cover 4.
An optical section 33 is attached to the photosensitive surface 4 for scanning the beam.

Next, the mounting structure of the basket 19 and the image forming section 20 is shown in FIGS. 1, 5, and 6. FIG. 1 is a vertical cross-sectional side view showing the support structure for the basket 19 and the image forming section 2°, FIG. 5 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. The image carrier 2 protrudes from both outer sides of the support body 23 as stop protrusions.
A guide groove 3 that guides a bearing 35 that supports 4 in a vertically movable manner.
6, and a guide groove 38 for vertically movably guiding a support shaft 37 protruding from both sides of the toner container 30 as a locking protrusion of the image forming section 20 are formed. Further, the transfer section 1
5 and the peeling portion 16 are positioned on a frame 39 fixed to the upper cover 3 and fixed with screws, and the bearing 35 or the support shaft 3 is attached to the frame 39.
Grooves 40 and 41 are formed to hold the image carrier unit 7 so as to be movable downward by 1 inch, and a support portion 42 is provided upright to abut the lower end of the waste toner container 27 of the image carrier unit 21.

These grooves 4o and 41 have a shape that widens toward the top.

Furthermore, the image carrier unit 21 is attached to the frame 39.
A locking means 43 is provided which resiliently engages. This locking means 43 includes a lock lever 45 that rotates around a movable fulcrum 44 and a lock lever 47 that rotates around a support shaft 46 .

These lock levers 45, 47 are connected to tension springs 48.
The upper part is urged in opposite directions by the urging forces of . The second part of one lock lever 45 has a downward slope 49 that presses the bearing 35 into the groove 40, an upward slope 50 that bends in the opposite direction from one end of the downward slope 49, and a downward slope 50 that bends in the opposite direction from one end of the downward slope 49. A receiving portion 63 facing horizontally from the lower end of the slope 49 and receiving the bearing 35 is formed, and the other lock lever 47 has a receiving portion 63 formed integrally with the outer surface of the support 23 of the image carrier unit 21. A downward slope 5 that presses a bottle-shaped locking protrusion 51
2, and an upward slope 53 bent in the opposite direction from the upper end of the downward slope 52.

As shown in FIG. 3, the movable fulcrum part 44 has a support shaft 44b inserted into a long hole 44a formed in the frame 39 so as to be vertically movable, and this support shaft 44b is fixed by a stop 44c. This support shaft 44b, which serves as a pivot point for the lock lever 45, is displaced in the vertical direction by loosening a nut 44c.

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 handles 56 are integrally formed on both outer sides 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 groove 41 is located closer to the image carrier 24 than the center of gravity of the developing unit 22 and closer to the developing roller 31.
It is located in the second part. Furthermore, the developing unit 22
A motor 58 for driving the developing roller 31 and the stirring blade 32 is fixed thereto, and a power input terminal 59 connected to the motor 58 is provided to protrude downward. A knife-shaped connector 60 that elastically clamps 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 groove 41 . Furthermore, as shown in FIG. 7, the toner container 3 is provided on the inner surface of the top cover 4.
A facing portion 62 facing each other with a predetermined gap S is formed in a part of 0.

FIG. 8 is a partial front view showing a state in which the support shaft 37 of the developing unit 22 is fitted into the groove 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 negative side of the upper cover 3, and in this state, the basket 19 is attached to the image carrier unit 21 by grasping the handle 34. When it is pulled up together with the developing unit 22, the paper conveyance path 8 is opened. Alternatively, the finger rests of the handles 54 and 56 are located at the portions 55a and 57a.
It is also possible to remove the image carrier unit 21 and the developing unit 22 individually with the basket 19 positioned inside the upper cover 3 by hooking a finger on the upper cover 3 and pulling it up.

When reassembling after jam removal or maintenance, the Vasquera I.19 taken out from the outside of the upper cover 3
The bearing 35 of the image carrier unit 21 is inserted into the guide groove 36 , and the support shaft 37 of the developing unit 22 is inserted into the guide groove 38 .
, grasp the handle 34 of the basket 19, and remove the bearing 3.
5 into the groove 40 of the frame 39, and the support shaft 3
7 is fitted into the groove 41, and the basket 19 is stored in the upper cover 3. Alternatively, the image carrier unit 21 and the developing unit 22 may be inserted into the basket 19 without fitting the bearing 35 or the support shaft 37 into the guide grooves 36, 38, 40, and 41 of the basket 19 housed in the upper cover 3.
Store it in. At this time, the bearing 35 whose movement in directions other than the vertical direction is regulated by the guide groove 36 and the groove 40 is moved to the lock lever 4.
The locking protrusion 5 is supported by the upward slope 50 of the locking protrusion 5
1 is supported by the upward slope 53 of the lock lever 47, but 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 is rotated counterclockwise against the force of the tension spring 48 by the force generated by the contact between the bearing 35 and the upward slope 50, allowing the bearing 35 to move downward. . 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 tension 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 tension spring 48, clamps the bearing 35 between its downward slope 49 and the receiving portion 63, and the lock lever 47 pushes the locking protrusion 51 downward with its downward slope 52. Then, the lower edges of both sides of the support body 23 are pressed against the support part 42. At this time, the bearing 35 is held so as to face the corner of the downward slope 49 and the receiving part 63 that intersect at an acute angle, and
Since lateral movement is restricted by the groove 40, there is no slight movement. Even when the image carrier 31 rotates, the bearing 35 itself located at the center of rotation does not vibrate. Thereby, vibration of the image carrier 24 can be effectively prevented. Further, the groove 40 is formed to be somewhat deep in order to allow the bearing 35 to move in the vertical direction, but the position of the bearing 35 is determined by the receiving portion 63 of the lock lever 45. The position of this receiving portion 63 is determined by adjusting the rotational torque of the lock lever 45. That is, Natsu 4.
By loosening 4c and displacing the movable fulcrum part 44 in the vertical direction, the distance Q (see FIG. 2) between the movable fulcrum part 44 and the anchoring point of the tension spring 48 changes. In other words,
The torque for rotating the lock lever 45 clockwise changes. Therefore, the downward position of the image carrier 24 can be accurately determined by the receiving part 63 of the lock lever 45 and the supporting part 42, and the lateral position can be determined by the engagement between the bearing 35 and the groove 40. .

The developing unit 22 is supported by its own weight with a support shaft 37 positioned in a groove 41.
The image carrier 2 is located above the center of gravity of the developing unit 22.
4 side, the developing unit 22 rotates clockwise around the groove 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,
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 counterclockwise against the force of the tension spring 48. Similarly, the locking protrusion 51 presses the downward slope 52 of the lock lever 47, and the force generated by the contact between the two causes the lock lever to move. -47 rotates clockwise against the force of the tension spring 48, allowing the locking protrusion 51 to move upward.

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 L-tub cover 4 to the support body 23.

The lower body 1 has a large number of parts attached to it via the frame 39, and has high rigidity because it can hold even heavy parts.It also has low vibration because it is placed on a stable stand or desk. As described above, the bearing 35 of the image carrier 24
Since the movement of is reliably fixed, there is no fear 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 1,
The bearing 35 and the locking protrusion 51 are connected to the lock levers 45, 47.
The image forming section 2o is temporarily supported by the upward slope 50.53 of the image forming section 2o.
When the lock lever 44 is pushed down, the force generated by the contact between the bearing 35 or the locking protrusion 51 and the upward slope 50.53 causes the lock lever 44,
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.
It is possible to raise the lock lever by 1 in one direction of 0.53, thereby eliminating the need to manually operate the lock levers 45 and 47, thereby improving operability.

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 precision. 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. Further, as shown in FIG. 9, a protrusion 37a may be formed at the end of the support shaft 37. This protrusion 37a comes into contact with the side surface of the frame 39 and acts as a guide member when the support shaft 37 is fitted into the groove 41, and also prevents the developing unit 22 from swinging in the left-right direction, and prevents the frame 39 from being deformed. Even if the width dimension of the frame 39 increases, the width dimension of the frame 39 can be corrected by fitting the support shaft 37 into the groove 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 side, and the locking protrusion is pressed by the downward slope to release the image forming section. By pressing a part of the lock lever against the support part and holding the locking protrusion without any play between the receiving part of the lock lever having a receiving part and the downward slope, vibrations are transmitted to the image forming part. This eliminates the need for a pressing member to press the image forming section on the upper main body, thereby reducing vibrations transmitted from the upper main body to the image forming section. Furthermore, by displacing the rotation center of the lock lever with the receiving part at the movable fulcrum part,
The pressing force of the lock lever against the locking protrusion can be adjusted, and the receiving part of the lock lever can be used to position the locking protrusion in the height direction, while the support part can be used to position the image forming section in the height direction. Furthermore, 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 By raising the image forming section above the upward slope, the image forming section can be released from the lock lever, thereby eliminating the need to manually operate the lock lever and improving operability. By attaching the forming section and the transfer section to a common lower body, the relative positions of both can be determined accurately, and furthermore, the image forming section can be attached and detached from above the lower body perpendicular to the axial direction of the image carrier. This has the effect of reducing the work space.

[Brief explanation of the drawing]

The drawings show one embodiment of the present invention, and FIG.
The figure is a side view showing the relationship between the lock lever receiving part and the bearing.
Fig. 3 is a longitudinal side view showing the structure of the movable fulcrum part of the lock lever, Fig. 4 is a longitudinal side view showing the overall structure, Fig. 5 is an exploded perspective view showing the relationship between the lower body and the basket, and Fig. 6. 7 is a plan view of the basket in which the image forming section is housed, FIG. 7 is a longitudinal side view of the developing unit, and FIGS. 8 and 9 are partial front views of the frame showing the mounting state of the developing unit. be.

Claims (1)

[Claims] 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 incorporated, and an image carrier unit including an image bearing member and a developing unit are formed. A plurality of locking protrusions are provided on both sides of the forming part,
A support part that abuts a part of the image forming section including the locking protrusion from below and a groove for vertically movably holding at least one of the locking protrusions are formed on both sides of the lower main body; A plurality of lock levers each having a downward slope abutting the locking protrusion and an upward slope bending in the opposite direction from the upper end of the downward slope are provided on the lower body so as to be biased in one direction and rotatable. , a receiving part is formed on at least one of the lock levers to support the locking protrusion so as to face substantially horizontally from the lower end of the downward slope, and a pivoting center of the lock lever having the receiving part is formed. An image forming apparatus characterized by being provided with a movable fulcrum section that is movably held.