JPS63269182A - Separating claw for separating transfer paper - Google Patents

Abstract

PURPOSE:To enable a user to simply replace a separating claw in each unit by constituting the separating claw so that a holder is engaged with an image forming case together with a holder cover, positioned, pressed and fixed by a plate spring, and then detached from the case together with the holder cover against the elastic force of the plate spring to detach the separating claw. CONSTITUTION:Fixed contact pressure is applied to the side of a photosensitive drum 3 by a spring built in the holder 1 for the separating claw 2 and the holder 1 is pivoted by an axial part together with holder cover 3 and positioned by engaging a rib of the holder cover 3 with a groove of the image forming case 4. The holder cover 3 is pressed and fixed by the plate spring 5 fitted to the case 4 to fix the holder 1. In order to replace the separating claw, the holder 1 is detached from the case 4 together with the holder cover 3 against the elastic force of the plate spring 5 and then the separating claw is detached from the holder 1 to replace the separating claw 2 by a new one.

Description

Detailed Description of the Invention (Field of Industrial Application) The present invention is a method for separating transfer paper from a photoreceptor after a transfer process in non-impact printers and copying machines using electrophotography. Regarding nails.

(Prior Art) In a conventional machine of this kind, there is a step of separating the transfer paper from the photoreceptor drum after transferring the toner image on the photoreceptor drum to the transfer paper.

Normally, a photoconductor drum with a curvature of about φ40m or less can be separated from the photoconductor drum only by the rigidity of the transfer paper, but when using a photoconductor drum with a curvature larger than that, an AC charger is required. Many machines have a separation charger that is applied from the back side of the transfer paper, but even in such cases, separation may be difficult when using transfer paper with poor separation performance or depending on the environmental conditions. Therefore, in order to prevent the transfer paper from rotating and operating while attached to the photosensitive drum without being separated, a separation claw is used after the separation charger.

As shown in FIG. 9, the separation claw 2 is attached to a support holder 2b which is pivoted to a support shaft 2a arranged parallel to the longitudinal direction of the photoreceptor drum 6. A spring 2d is tensioned on the support holder 2b so as to press against the photoreceptor drum 6. Also,
The separating claw is made of stainless steel and has a thickness of about 0.3 mm to 0.5 mm, and the tip has a sharp edge.

If such a separation claw is used for a long period of time, the tip of the edge portion will eventually wear out, damaging the photoreceptor drum surface and reducing transfer paper separation performance, so periodic replacement is required. Become.

In the past, replacement was done by service personnel, but recently some models have been replaced by the user. Especially in the case of printers, the photoconductor unit, cleaning unit, and toner cartridge unit are housed in an image forming case, and each can be replaced by the user. It has become more common to replace them on a regular basis. In this case, with the separation claw mounting structure as shown in FIG. 9, it is difficult to replace each unit.

(Problems to be Solved by the Invention) The present invention solves the drawbacks of the above-mentioned prior art,
In non-impact printers and copying machines that use electrophotography, the separation claw can be easily replaced by the user on a unit-by-unit basis to prevent transfer paper from rotating while attached to the photoreceptor drum. In addition to making it possible to
The separation claw is positioned so as to have a constant contact pressure against the photosensitive drum side.

(Means for Solving the Problems) In order to achieve the above object, the present invention has a holder for a separation claw that is pivotally attached to the holder cover, and a spring built into the holder to center the separation claw on the shaft of the holder. A constant contact pressure is applied to the photoreceptor drum side, the holder and the holder cover are fitted and positioned in the image forming case, and the holder cover is pressed and fixed by the leaf spring and attached.

The separation claw can be removed by removing the holder together with the holder cover from the imaging case against the elasticity of the leaf spring, and then removing the separation claw from the holder.

(Function) In the present invention, a spring built into the holder of the separation claw applies a constant contact pressure to the photosensitive drum side, the holder is supported by the holder cover and the details, and the ribs of the holder cover are attached to the imaging case. The holder cover is positioned by fitting into the groove of the image forming case, and the holder cover is pressed and fixed by a leaf spring attached to the image forming case. To remove the holder for replacement, remove the holder together with the holder cover from the imaging case against the elasticity of the leaf spring, remove the separation claw from the holder, and replace the holder with a new one.

(Embodiment) FIG. 1 shows an assembled external view of a separation claw for separating transfer paper according to an embodiment of the present invention, and 1 is a circular mold-shaped separation claw holder;
The shaft portion 11.11' is the bearing 31.31' of the holder cover 3.
supported by. Reference numeral 12 denotes a tongue-shaped mounting member for mounting the separation claw 2, and the separation claw is fixed to the mounting member 12 by a mounting screw 21. 13 is a spring, which is connected to the shaft portion i1 of the holder 1. tt' and the holder cover 3 (■-■) to apply a constant contact pressure. 32° 32' of the holder cover is the pressing surface of the leaf spring 5 attached to the image forming case 4 with mounting screws 51 and 51';
33' is a rib that fits into the fitting groove 41, 41' of the image forming case 4.

When attaching the separation claw holder to the imaging case or replacing it with a new one, the following procedure is performed.

The separated holder 1 has a holder cover 3 and shaft parts 11 and 1, respectively.
1' and bearings 31 and 31', and are integrated, and due to the elasticity of the spring 13, the second
A constant contact pressure is applied to the photosensitive drum 6 side shown in the figure. The ribs 33, 33' of the holder cover 3, which is integrated with the holder configured in this way, are fitted into the fitting grooves 41, 41' of the imaging case 4, and the holder and the holder cover are aligned at a predetermined position. Next, the spring portions 52, 52' of the leaf springs 5, which have already been attached to the imaging case, are applied to the suppressing surfaces 32, 32' of the holder cover 3, and the holder cover is pressed and fixed onto the imaging case 4. As a result, as shown in FIG. 2, the one-separation claw 2 is easily set against the photosensitive drum 6 with a constant contact pressure.

In addition, when replacing the separation claw 2, the rib 33, 33' of the holder cover and the fitting groove 4 of the image forming case 4 must be replaced against the elasticity of the leaf spring 5.
1.41', take out the holder together with the holder cover, and replace the separating claw 2 with the mounting screw 21.The subsequent setting in the image forming case 4 is as described above.

Now, as mentioned above, regarding periodic replacement parts that used to be done by service personnel, especially in the case of printers,
Recently, there have been many requests from users to perform exchange.

Conventionally, from this point of view, the developing unit, photoconductor unit, cleaning unit, toner supply unit, etc. were configured as one unit, and if a unit reached the end of its replacement life after a certain period of time, other replacement units could still be used. Even though it was replaced as a whole. For this reason, the cost of each component is high, and therefore the running cost is inevitably high.

This has the drawback of imposing a heavy burden on the user.

Therefore, in order to eliminate this drawback, there is also a method in which an individual replacement cycle is set for each replacement unit and each replacement unit is replaced individually. This requires a pull-out mechanism for each replacement unit and requires accurate positioning between each unit;
In addition, each replacement unit is located in a narrow space, making it difficult to replace the unit, damaging other units when pulled out, and causing toner to fall and stain the interior. Alternatively, there is a method in which each unit is used as an image forming unit and the entire unit is pulled out from the main body of the apparatus and each unit is replaced. This has the disadvantage that each unit is positioned with the precision necessary for operation within the entire device and is pulled out as it is, making it difficult to remove the unit.

In order to solve these problems, an example of a device for replacing image forming units such as photoreceptor units, developing units, and cleaning units in non-impact printers and copying machines that use electrophotography will be described below. .

FIG. 3 is a perspective view of the laser printer in which the drawer 11 holding the image forming unit (replaceable unit) is pulled out from the laser main body 10. FIG. 4 is a cross-sectional view of a portion of the drawer shown in FIG. 3.

As shown in FIGS. 3 and 4, in the laser printer of this example, a drawer 11 is slidably attached to one side of a main body 10 by support guide rails 12 and 12'.

The drawer 11 includes a photoreceptor unit 13. Developing unit 1
4. Cleaning unit 15. Toner cartridge 1
An image forming unit such as 6 is removably housed. When the drawer 11 is pushed into the main body 10, these units are installed in an appropriate positional relationship with each other so that the electrophotographic recording operation can be performed correctly, and the optical units provided on the main body 10 side are System unit 21. Electrostatic charger 22. Static elimination lamp 23. Transfer charger 24.
It is positioned so as to maintain an appropriate positional relationship with the registration rollers 25 and the like.

By pulling the drawer 11 out of the main body 10, the developing unit 14 and toner cartridge 16 are automatically separated from the photoreceptor unit 13 to the right in FIG. 4, and the cleaning unit 15 is automatically moved to the left. Be separated. Due to this separation of the two units, when it comes time to replace one of the units and you remove it,
Since there is some space between adjacent units, one task becomes easier and the adjacent units are not damaged.

On the front of the drawer 11, there is a handle 17 for pulling out the drawer.
is installed. Also, a developing unit 14, a cleaning unit 15. Each of the toner cartridges 16 is also provided with a handle. however.

The handle is omitted and not shown in FIG.

The main body 10 includes a drawer 1 equipped with the above-mentioned image forming unit.
1 and an optical system unit 21 that optically scans the photoreceptor.
In addition to the other components, a fixing unit fixes the toner image on the recording paper developed by the first paper supply cassette 18 and the second supply cassette 18' that supply the recording paper and one image forming unit by heating and applying pressure. 27. It includes a transport section 26 and the like. In addition, a first section is provided at the top of the printer main body 10 to receive recorded recording paper discharged via the conveying section 28.
A paper discharge tray 19 and a second paper discharge tray 19' are provided.

The printer main body 10 also includes a separate mass paper feed unit 20, which is used as an option, as needed.
-1 and a reversing unit (not shown) for reversing the recording paper recorded on one side after exiting the fixing unit 27 and supplying it to the image forming unit again. ing.

By raising the cover plate 11-1 and covering the drawer 11 with the drawer 11 housed in the main body, it is possible to prevent the intrusion of lumps and the like and improve the appearance of the drawer.

5 and 6 show an example of a mechanism for separating the cleaning unit 15 from the photoreceptor unit 13 by pulling out the drawer 11. FIG.

Slide hole 31. Cleaning unit holding notch 3
2. A pair of sliders 35 and 35' consisting of a spring support protrusion (pin) 33 and a cam contact part 34 are attached to the drawer 11.
The drawer 11 is slidably fixed to the drawer 11 by a guide pin 36. The spring 3 is placed between the spring support projection 33 of the slider 35 and the spring support pin 38 fixed to the bottom of the drawer 11.
9.

Further, the shaft rod 40 is passed between the front and rear side plates of the drawer 11, the cam 41 is fixed at a location corresponding to the position of the cam contact portion 34 of the slider 35, and the shaft rod 40 is attached so as to rotate in the axial direction. Attach the spring 37. Although such a cam and spring are not shown in FIG. 5, they are of course provided corresponding to the slider 35'. A cam 43 provided on the main body side is attached to the rear end of the shaft rod 40.
A pin 42 is provided to engage with.

The cleaning unit 15 has four pins provided at both its front and rear ends, two of which pins 44 and 44' are connected to the notches 32 and 32' of the slider 35, as shown in FIG.
The remaining two pins 45 and 45' are held by pin support portions 46 and 46' provided on the side wall of the main body, as shown in FIG. As shown in FIG. 8, the pin support portion 46, 46' has a pin slide elongated hole 47 for slidably supporting the pin in the sliding direction, and a notch above which serves as a pin insertion hole. It has 48.

In the drawer 11 holding the image forming unit configured as described above, in the operating position where it is housed in the main body 10, the pin 42 at the end of the shaft 40 is in contact with the cam at the back of the main body side cam 43. The spring 37 prevents the cam 41 from rotating. Therefore, slider 35.35'
Only the elastic force of the spring 39 acts effectively on the cleaning unit 1 supported by the slider 35, 35'.
5 is positioned close to the photoreceptor unit 13, which is the original operating position. That is, the cleaning unit 15 is pulled to the right in FIG. 5 by the spring 39 to a position defined as a reference position.

On the other hand, when the drawer 11 is pulled out, the pin 42 at the end of the shaft 40 extending from the front and back of the drawer 11 comes out of the cam 43 on the main body side, and the cam 41 receives the rotational force of the spring 37, causing the slider to slide. 35.35' contact part 3
4. Since the spring 37 is stronger than the spring 39, the slider 35 moves to the left in the figure, and as a result, the pin 44, 44' of the cleaning unit 15 is pulled. As a result, the cleaning unit 15 is separated from the photoreceptor unit 13.

Although only the cleaning unit 15 has been described above, the developing unit 14 also has a similar mechanism.
When the drawer 11 is pulled out, it can be separated from the photoreceptor unit 13.

In the above example, in order to automatically separate the units set in the drawer 11 when the drawer 11 is pulled out from the main body 10, the position of the drawer 11 is detected and the sliding operation of a predetermined unit is performed in accordance with the detection. This is achieved by a combination of multiple cam mechanisms, but it is not limited to such cam mechanisms, but can also be achieved by other means, such as a combination of electrical detection of the drawer position and an electromagnetic mechanism driven by it. be able to.

(Effects of the Invention) According to the present invention, the holder of the separation claw is pivotally attached to the holder cover, and the separation claw is applied with a constant contact pressure to the photosensitive drum side around the shaft of the holder by a spring built into the holder. The holder is positioned together with the holder cover by fitting the ribs of the holder cover into the fitting grooves of the imaging case.
The holder cover is pressed by the leaf spring and stabilized on the imaging case.

Securely fixed.

In addition, the separation claw can be easily replaced by removing the holder along with the holder cover against the elasticity of the leaf spring, loosening the mounting screws, and replacing it with a new one.

Easy to install and remove.

[Brief explanation of drawings]

FIG. 1 is an assembled external view of a separation claw for separating transfer paper according to an embodiment of the present invention, FIG. 2 is a side view of the separation claw holder shown in FIG. 1 set on a photosensitive drum, and FIG. 3 is a laser A perspective view of the printer; FIG. 4 is a cross-sectional view of a portion of the drawer in FIG. 3;
5 and 6 are diagrams showing an example of a mechanism for separating the cleaning unit 15 from the photoreceptor unit 13 by pulling out the drawer 11, and FIG.
FIG. 8 is a diagram showing the support portion of the pin, and FIG. 9 is a diagram showing the structure of a conventional separating claw. DESCRIPTION OF SYMBOLS 1... Holder, 2... Separation claw, 3... Holder cover, 4... Imaging case, 5... Leaf spring, 6
...Photosensitive drum, 11.11'...Shaft of holder, 12...Mounting member, 13...Spring, 21...Separation claw mounting screw, 31.31'...
・Holder bearing, 32, 32'...pressing surface, 33
．． 33'...rib, 41.41'...fitting groove,
51.51'...Flat spring installation screw, 52.52'
...Spring part. Patent Applicant Rico Co., Ltd. Part 1 Figure 1 - Holter No. 2 - Insertion 3 - Holder No. 4 -
11.11'-Shaft part 13-
, Suzu Song 21 - Collection Neshi. 31.31'-Glaze fe32.32'-O T pressure surface 33.3
3'-Riff "41.4+'-4 Matching groove 51.51'-1 Mounting screw 52.52'-Spring part Fig. 2 1-Js holder 2-R1!a3-Ts rule 'f'J/
(-4-imaging case 5-alj wa 6.-front Hayashi drum 3rd figure +1"' drawer 12...support hiderere 13...successful unit, +4-item l unit 15" ...Cleaning unit, Figure 4 δ°゛° Place I in run 7+ 24... Coarse #+E Figure 5 31 Slide hole 32, Unit excellent 4
Eki ρ sword uyu shin 33.44.44', 45 ・-bin
35, 35'...Sliter. District 6, Figure 7, Figure 9

Claims (1)

[Claims] The separation claw holder is pivotally attached to this holder cover, and a spring built into the holder applies a constant contact pressure to the photosensitive drum around the shaft of the holder, and the holder is assembled together with the holder cover. The holder cover is fitted and positioned in the image case, and the holder cover is pressed and fixed by the leaf spring, and the separation claw is removed by resisting the elasticity of the leaf spring to remove the holder together with the holder cover from the imaging case, and then remove the separation claw from the holder. A separation claw for separating transfer paper, characterized in that it is configured to be removable.