JP2611771B2 - Imaging device - Google Patents

Description

The present invention relates to a non-impact printer, a facsimile,
The present invention relates to an image forming apparatus for an apparatus having a recording unit using an electrophotographic method, such as a copying machine, and particularly to a transfer charger for transferring a toner image on a photoconductor (a transfer charger and a separation charger are integrated into a transfer charger. (Including those that are available).

(Prior art) The processes of an electrophotographic printer, facsimile, and copier except for the optical system are almost the same, toner replenishment is required, and photoreceptors, development, cleaning, chargers, and the like are required. Has units that need to be replaced.

By the way, recently, of course, toner supply,
Machines that replace the charging unit and the transfer charger of the cleaning unit by a user have been commercialized.
Particularly in printers, user maintenance is strongly required, and it is becoming a necessary condition that the user can easily exchange each exchange unit.

In an example of this type of conventional apparatus, units related to image formation that need to be replaced, such as a photoreceptor unit, a developing unit, a cleaning unit, and a transfer charger, are taken out of the machine main body individually or as a united cartridge, and are replaced. Or, it is configured to supply toner. Alternatively, it is conceivable to set an image forming unit in one case so that the unit can be pulled out from the main body for easy replacement, pull out the entire case from the machine main body, and replace each unit individually. In any case, since the transfer charger is set on the main body, it is easy to position each unit. However, the replacement of the unit is troublesome, and since the replacement of the unit is performed by a service person in principle, the request of the user maintenance cannot be met.

The exchange method can be roughly divided into two.

One is a system in which each unit is individually pulled out from the machine main body and exchanged. Each VW unit related to image formation is formed in one cartridge, and exchange is performed in units of this cartridge.

In the other, the units related to image formation are housed in one case, but the units are individually replaced.

In each of such conventional examples, the transfer charger is set in the machine main body in order to facilitate processing when paper jam occurs.

(Problems to be Solved by the Invention) In a recording unit such as a non-impact printer, a facsimile or a copying machine using an electrophotographic system, the positional relationship between the charger wire position of the transfer charger and the photosensitive member is extremely high. However, in the conventional configuration, the image forming unit such as the photoconductor, the developing unit, and the cleaning unit is detachably attached to one drawable image forming case, and the transfer charger is provided in the main body. It has been difficult to improve the positional relationship with the wire position with high accuracy.

Also, when pulling out the image forming case, when pulling out the developing unit and cleaning unit, if toner spills out of the opening of the photoconductor set section of the image forming case, there is no tray portion to receive the toner, so toner spilling may occur. It falls on the floor and gets dirty.

The present invention eliminates such a conventional problem and provides an image forming apparatus that can obtain high accuracy of the positional relationship between the transfer charger and the photoreceptor, that is easy for user maintenance, and that reduces toner spills on the floor. It is intended to provide.

(Means for Solving the Problems) In the image forming apparatus according to the present invention, the photosensitive unit is detachably housed as a replacement unit together with the developing unit, the cleaning unit, and the toner cartridge, and is housed. Replacement unit that is slidable relative to the machine body, and is provided at the lower portion of the replacement unit holding unit so that the transfer charger unit can be pulled out to the outside. Transfer charger unit holding means for slidably holding the transfer charger unit held at a transfer position with respect to the photoconductor unit by the transfer charger unit holding means. Characterized by functioning as a receiver It is.

Further, the image forming apparatus according to claim 2 is characterized in that the transfer charger unit holding means is coupled to a lower portion of the replacement unit holding means so as to be openable downward.

(Operation) According to the image forming apparatus of the present invention, the transfer charger unit held at the transfer position with respect to the photoconductor unit by the transfer charger unit holding unit falls from the replacement unit holding unit. By functioning as a toner receiver for receiving toner, when the replacement unit holding means containing the replacement unit is pulled out of the machine body, the transfer charger unit held at the transfer position by the transfer charger unit holding means also moves together, Since the transfer charger unit receives the toner dropped from the replacement unit holding means, it is possible to prevent the toner from being stained. Further, since the photoconductor unit and the transfer charger unit are supported by the same exchange unit holding means, the positional accuracy of both units can be kept high.

Further, according to the image forming apparatus described in claim (2), the transfer charger unit holding means is coupled to the lower part of the replacement unit holding means so as to be able to be separated downward, so that the replacement unit holding means is provided. If the transfer charger unit holding means is opened downward by being pulled out from the machine main body, processing operations such as paper jam can be facilitated.

(Embodiment) FIG. 1 is a perspective view of a laser printer according to an embodiment of the present invention. An imaging case (drawer) in which an imaging unit including a transfer charger is set is drawn out of the laser printer main body. The state is shown. FIG. 2 is a diagram showing a cross section of FIG.

As shown in FIGS. 1 and 2, an image forming case 2 is slidably mounted on one side surface of a main body 1 of a laser printer of this embodiment by supporting guide rails 3, 3 '.

In the image forming case 2, image forming units such as a photoreceptor unit 4, a developing unit 5, a cleaning unit 6, and a toner cartridge 7 are detachably stored. Further, a transfer charger unit 8 is detachably attached to a lower portion of the image forming case 2. When the imaging case 2 is pushed into the main body 1, these units are mounted while maintaining an appropriate positional relationship with each other so that the recording operation by the electrophotographic method is correctly performed, and provided on the main body 1 side. The optical writing unit 21, the charging charger 22, the registration roller 23 and the like are also positioned so as to maintain an appropriate positional relationship.

When the image forming case 2 is pulled out of the main body 1, the developing unit 5 and the toner cartridge 7 are automatically separated from the photoreceptor unit 4 to the right side in FIG. To be separated. Due to such isolation of the units, when any one of the units is to be removed at the time of replacement, some space is left between the adjacent units, so that the operation is simplified and the adjacent units are not damaged.

A handle 9 for pulling out is provided on the front of the imaging case 2.
Is attached. The developing unit 5, the cleaning unit 6, and the toner cartridge 7 are also provided with handles. However, the handle is omitted in FIG. 2 and is not shown. In addition, regarding the transfer charger unit attaching / detaching mechanism which is a feature of the present invention,
Details will be described later.

The printer body 1 includes an image forming case 2 on which the above-described image forming unit is mounted, an optical writing unit 21 for optically scanning the photoconductor unit, and other components. Paper cassette 11 and second paper cassette 12
And a fixing unit 27 for fixing the toner image on the recording paper developed by the image forming unit by heating and pressing, a transport unit 26, and the like. Further, a first paper discharge tray 15 and a second paper discharge tray 16 for receiving the recorded recording paper discharged through the conveyance path 28 are provided at an upper portion of the printer main body 1.

Further, the printer body 1 includes a separate large-volume paper feed unit 14 that is used as necessary as a so-called option,
A reversing unit 13 for turning over the recording paper recorded on one side exiting the fixing unit 27 and supplying it again to the image forming unit
It is mounted on an optional unit 18 consisting of

By raising and covering the cover plate 10 in a state where the image forming case 2 is housed in the main body, it is possible to prevent dust and the like from invading and to adjust the appearance.

FIGS. 3 and 4 show an example of a mechanism for separating the cleaning unit 6 from the photoconductor unit 4 by pulling out the image forming case 2. FIG.

Slide hole 31, cleaning unit holding notch 3
2. A pair of sliders 35 and 35 'each including a spring support projection 33 and a cam contact portion 34 are disposed before and after in the drawing direction of the imaging case 2 and are slidably fixed to the imaging case 2 by guide pins 36. I do. Then, a spring 39 is stretched between the spring support projection 33 of the slider 35 and the spring support pin 38 fixed to the bottom of the imaging case 2.

Also, pass the shaft bar 40 between the front and rear side plates of the imaging case 2,
The cam is placed at the position corresponding to the position of the cam
41 is fixed, and a spring 37 for urging the shaft bar 40 to rotate in the axial direction is attached. Although not shown in FIG. 3, such cams and springs are provided corresponding to the slider 35 '. A pin 42 is provided at the rear end of the shaft 40 so as to engage with a cam 43 provided on the main body side.

The cleaning unit 6 has four pins provided at both front and rear ends thereof, of which two pins 44 and 44 'are fitted into the notches 32 and 32' of the slider 35 as shown in FIG. As shown in FIG. 5, the remaining two pins 45, 45 'are held by the slider 35, and the remaining two pins 45, 45'
6,46 '. As shown in FIG. 6, the pin bearing portions 46 and 46 'have a pin sliding slot 47 for slidably supporting the pin in the sliding direction, and a notch 48 serving as a pin insertion port is provided above the pin sliding slot 47. Have.

In the image forming case 2 holding the image forming unit configured as described above, the pin 42 at the end of the shaft 40 is located at the back of the main body side cam 43 in the operating position where the image forming unit is stored in the main body 1. , And prevents the spring 37 from rotating the cam 41. Therefore, only the elastic force of the spring 39 acts effectively on the sliders 35, 35 ', and the cleaning unit 6 supported by the sliders 35, 35' is positioned close to the photosensitive unit 4, which is the original operating position. . That is, the cleaning unit 6 is set to a position (reference position) which is pulled rightward in FIG.

On the other hand, when the imaging case 2 is pulled out, the pin 42 at the end of the shaft
However, it comes off from the cam 43 on the main body side, and the cam 41 receives the rotational force of the spring 37 and pushes the contact portion 34 of the slider 35, 35 '. The spring force of the spring 37 is 39
Since the stronger one is used, the slider 35 is moved to the left side of the drawing, and as a result, the cleaning unit 6 is pulled by pulling the pins 44, 44 'of the cleaning unit 6.
Moves away from the photoconductor unit 4.

Although only the cleaning unit 6 has been described above, the developing unit 5 can be separated from the photoconductor unit 4 when the image forming case 2 is pulled out by the same mechanism.

In the above embodiment, when the image forming case 2 is pulled out from the main body 1, the position of the image forming case 2 is detected and the detection is performed in order to automatically separate the units set in the image forming case 2. Is performed by combining a plurality of cam mechanisms with the sliding operation of a predetermined unit corresponding to
The present invention is not limited to such a cam mechanism, and can be realized by a combination of other means, for example, an electrical detection of an image forming case position and an electromagnetic mechanism driven thereby.

FIG. 7 shows a mechanism for attaching the transfer charger unit 8 to the image forming case. In this embodiment,
The transfer charger unit 8 is configured as a transfer charger 50 having a function as a transfer and separation charger, and the transfer charger 50 is held by a transfer charger holder 60. The transfer charger 50 includes a transfer charger section 52, a separation charger section 53, a rib 54 for facilitating sheet feeding,
It comprises an electrical connection 55 with the body and a handle 56. The transfer charger 50 is detachably held by a transfer charger holder 60. The transfer charger holder 60 can be inserted into the transfer position for transferring the toner image on the photoreceptor unit 4 by sliding the transfer charger 50 from the front portion, or can be pulled out and inserted. Rails 61 are formed on both sides to hold the transfer charger 50. The image forming case 2 is provided with an engagement projection 64 having a hole 63 for receiving a pin in a lower part at a position where the photoconductor unit 4 is located. A pin 62 is provided at one end of the rear of the transfer charger holder 60, and the pin 62 is engaged with the hole 63 of the engagement protrusion 64. The holder 60 is pivotally supported so as to be able to rotate downward.

The front end portion 66 of the transfer charger holder 60 is bent into an L shape, and an elastic member 67 such as rubber or soft resin is attached to the end thereof, and the transfer charger holder 60 rotates downward. This prevents the front end of the printer from hitting and damaging the outer wall surface of the printer body. Further, a lock lever 70 having a handle 68 and an engaging portion 69 is rotatably connected to a front end 66 of the transfer charger holder 60 via a pin 71.

On the front side of the imaging case 2, an engagement portion of the lock lever 70 is provided.
A support member 65 for engaging the 69 and supporting the transfer charger holder 60 is provided.

In the above configuration, when replacing a unit or processing a paper jam, the image forming case 2 is pulled out of the printer main body 1 as shown in FIG. 1 by pulling the handle 9 toward the user. Since the predetermined units such as the cleaning unit 6 and the developing unit 5 are automatically separated from the photoreceptor unit 4 in accordance with the pull-out, there is a margin in the space between the units, so that the units can be easily replaced. In addition, when replacing each unit, adjacent blades which are easily damaged, for example, the photosensitive unit 4 and the blade of the cleaning unit 6 are not damaged, and the cleaning unit 6 and the developing unit 5 are not damaged.
The replacement unit can be taken out with less toner spilling from the unit.

Further, even if the toner is spilled from the lower opening at the set position of the photoconductor unit 4 when the imaging case 2 is pulled out, the transfer charger 50 held at the transfer position by the transfer charger holder 60 is formed. Since the toner has a function as a toner receiver for receiving the toner drawn out together with the image forming case 2 and spilled from the opening of the image forming case 2, the toner does not spill out from the opening to the floor when the image forming case 2 is pulled out. Absent.

Further, in the use state where the image forming case 2 is housed in the printer body 1, even if toner is spilled from the cleaning unit or the developing unit, the transfer charger is used.
It can be received at 50 and can prevent the inside of the main body from being contaminated.

When processing a paper jam or the like, pull out the imaging case 2 from the printer body 1 and then pull the handle 68 forward to release the lock of the lock lever 70 to hold the transfer charger holder 60 and the transfer charger holder 60 therewith. The transferred transfer chargers 50 rotate together with the pin 62 as a rotation center and separate from the photoreceptor unit 4, so that a paper jam can be easily handled.

Also, when replacing the transfer charger 50, or when collecting and discarding toner spilled on the transfer charger, the handle 56 can be pulled to pull the transfer charger.
50 can be taken out.

(Effects of the Invention) According to the present invention, the photoconductor unit and the transfer charger are attached to the same image forming case, and move integrally when the image forming case is taken in and out, and the mutual positional relationship is constant. In addition, there is an advantage that the positional accuracy between the photosensitive member unit and the transfer charger can be easily obtained.

In addition, since toner transfer from the cleaning unit and the developing unit is received by the transfer charger unit, it is possible to prevent toner contamination in the main body and spillage of toner on the floor when the image forming case is pulled out.

[Brief description of the drawings]

FIG. 1 is a perspective view of a laser printer according to an embodiment of the present invention, and FIG. 2 is a diagram showing a partial cross section of the image forming case of FIG. FIGS. 3 and 4 are views showing an example of a mechanism for separating the cleaning unit 6 from the photoconductor unit 4 by pulling out the image forming case 2. FIG. FIG. 5 is a diagram showing a mechanism for supporting the cleaning unit 6 on the image forming case 2,
FIG. 6 is a view showing a pin support. FIG. 7 is a diagram showing a mechanism for attaching the transfer charger unit to the image forming case. 1 ... printer body, 2 ... image forming case, 3, 3 '...
Supporting guide rail, 4 ... Photoreceptor unit, 5 ... Developing unit, 6 ... Cleaning unit, 7 ... Toner cartridge, 8 ... Transfer charger unit, 9 ... Handle, 10 ... Cover plate, 11,12 ... ... Paper cassette, 13 ... Reversing unit, 14 ... Large paper feed unit, 15,16 ... Eject tray, 17 ... Display unit, 18 ... Option unit, 21 ...
... Optical writing unit, 22 ... Charging charger, 23 ... Registration roller, 26 ... Conveying belt, 27 ... Fixing unit, 31 ... Slide hole, 32,32 '... Unit holding notch, 33, 44,44 ', 45,45' ... pin, 35 ... slider, 36 ... guide pin, 37,39 ... spring, 40 ...
Shaft, 41, 43… Cam, 50… Diversion charger, 52…
Transfer charger section, 53 Separation charger section, 54 Rib, 55 Electrical connection with main body, 56 Handle, 60
Transfer charger holder, 61… Rail, 62… Pin, 63
… Hole, 64… engaging protrusion, 66… front end, 67… elastic member, 68… grip, 69… engaging part, 70… lock lever,
71 ... Pin.

Claims (2)

(57) [Claims] 1. A photoreceptor unit is detachably housed together with a developing unit, a cleaning unit and a toner cartridge as an exchange unit, and the accommodated exchange unit is integrally slidable relative to the machine body to be integrally pulled out from the machine body. And a transfer charger unit holding means provided below the replacement unit holding means and slidably held back and forth for pulling out the transfer charger unit to the outside. The transfer charger unit holding means An image forming apparatus, wherein the transfer charger unit held at a transfer position with respect to a photoreceptor unit functions as a toner receiver for receiving toner dropped from the replacement unit holding means. 2. An image forming apparatus according to claim 1, wherein said transfer charger unit holding means is coupled to a lower portion of said exchange unit holding means so as to be opened downward.