JP2003131540A - Method for assembling photoreceptor drum driving device and method for assembling electrophotographic recording device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To securely prevent the occurrence of trouble due to the position relation between a drum driving shaft and a photoreceptor drum while preventing the product cost from increasing. SOLUTION: In the method for assembling the photoreceptor drum driving device 200 equipped with the driving shaft 202 which coaxially engages the photoreceptor drum, a 1st plane metal plate 203 which has a 1st hole part through which the driving shaft 202 is run, a 2nd metal plate 204 which stores a driving system 207 coupled with the 1st metal plate 203 to drive the driving shaft 202 and has a 2nd hole part through which the driving shaft 202 is run on a plane parallel to the 1st metal plate 203, and a reference member as a standard for forming the parallelism between the 1st metal plate 203 and 2nd metal plate 204, the reference member is inserted into the 1st hole part and 2nd hole part while the 1st metal plate 203 and 2nd metal plate 204 are made to meet each other and the 1st metal plate 203 and 2nd metal plate 204 are fixed while having their parallelism held on the basis of the reference member; and the reference member is detached and the driving shaft 202 is inserted into the 1st hole part and 2nd hole part.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a drive source such as a motor for transmitting power to a photosensitive drum, and a transmission means such as a gear, a timing belt, an electromagnetic clutch for transmitting power from the drive source to the photosensitive drum, A drum drive shaft that is coaxially engaged with the photosensitive drum, and two housings that face each other,
And an electrophotographic recording apparatus.

[0002]

2. Description of the Related Art Conventionally, in a photosensitive drum driving device and an electrophotographic recording device of this type, as means for transmitting power from a motor as a driving source to the photosensitive drum which is the most important part for forming an image. , Rotation unevenness due to speed fluctuations of frequency components depending on the number of meshed teeth, not so-called transmission means such as gears that accompanies jitter, but engages coaxially with the photoconductor drum and directly transmits power from the motor It is common to use a drum drive shaft.

Usually, each drive-related component which constitutes a transmission means such as a motor, a drum drive shaft and a gear is assembled as one drive unit and then fastened and fixed to a main body casing from the viewpoint of positioning and guarantee of characteristics. For example, the configuration is as shown in FIG.

In FIG. 13, the first sheet metal 1 having a planar shape is shown.
A second sheet metal 1302, which is bent by a pressing process or the like, is fixed to 301. First sheet metal 13
A fixed space is formed inside the second sheet metal 1302 fixed to 01, and a motor 1303 which is a drive source of the photosensitive drum is housed in this space. A gear 1304 formed at the shaft tip of the motor 1303 projects from a hole formed at a predetermined position of the second sheet metal 1302. This motor 1
A gear 1304 attached to the drum drive shaft 1305 meshes with a gear 1304 formed at the tip of the shaft of 303.
The drum drive shaft 1305 is inserted into holes 1301A and 1302A formed at predetermined positions of the first sheet metal 1301 and the second sheet metal 1302. Drum drive shaft 1305
Are held in these hole portions 1301A and 1302A via a shaft holding means such as a bearing 1307. The drive unit thus configured is fixed to the main body housing 1308. The photoconductor drum 1309 is attached to the portion of the drum drive shaft 1305 protruding inward from the main body housing 1308. Hereinafter, an assembly process of such a photosensitive drum driving device will be described.

First, as shown in FIG. 14, a second sheet metal 1302 having a motor 1303 as a drive source fixed at a predetermined position and manufactured by press working or the like is positioned on the first sheet metal 1301. For relative positioning of both, hole portions 1301A and 1302A formed at predetermined positions of both and hole portions 1301B and 1302B into which screws for fastening both are inserted.
Is used. Then, as shown in FIG.
By inserting screws into 01B and 1302B, the second sheet metal 1302 side and the first sheet metal 1301 are fastened and fixed.

After the first sheet metal 1301 and the second sheet metal 1302 are fixed, as shown in FIG. 16, the drum drive shaft 1305 having the gear 1306 attached thereto is inserted into the holes of the first sheet metal 1301 and the second sheet metal 1302. Parts 1301A and 1
Insert so as to penetrate 302A. At that time, the drum drive shaft 1305 is attached via a bearing 1307 so as to be rotatably held. This constitutes one drive unit.

After the drive unit is constructed, as shown in FIG. 17, the end portion of the drum drive shaft 1305 is attached to the main body housing 130.
The drive unit is attached to the main body housing 1308 so as to pass through the hole formed in 8 and project inward. And
At a predetermined position of the first sheet metal 1301, the drive unit side is fastened and fixed to the main body housing 1308 with screws.
Finally, as shown in FIG. 18, the drum drive shaft 1305 protruding inward from the main body housing 1308 is attached to the photosensitive drum 13.
It is inserted into the side surface of 09 to support the photoconductor drum 1309. In this way, such a photosensitive drum driving device is assembled.

[0008]

However, in the conventional assembling method as described above, the axis center of the drum drive shaft 1305 is the hole portions 1301A and 1302A formed in the first sheet metal 1301 and the second sheet metal 1302. Determined by relative position. Then, these hole portions 1301A and 1
The relative position of 302A is determined by the state of the second sheet metal 1302 fixed to the first sheet metal 1301.

That is, when the second sheet metal 1302 is appropriately bent and is properly fixed to the first sheet metal 1301, the center of the drum drive shaft 1305 is arranged at a predetermined position. By engaging the photosensitive drum 1309 with the drum drive shaft 1305, the power of the motor 1303 is properly transmitted to the photosensitive drum 1309. However, if the second sheet metal 1302 is fixed to the first sheet metal 1301 without being properly bent, the center of the drum drive shaft 1305 becomes improper and the motor 130
The power of No. 3 may not be properly transmitted to the photosensitive drum 1309.

FIG. 19 is a view showing a state in which the second sheet metal 1302 is fixed to the first sheet metal 1301 without being appropriately bent, and FIG. 20 shows the drum drive shaft 1305 in the state shown in FIG. The enlarged view of the drum drive shaft 1305 periphery when inserted is shown.

FIG. 19 shows a case where the length of the lower surface 1902 is bent shorter than the length of the upper surface 1901 shown in the drawing in the step of bending the second sheet metal 1302. By fixing the second sheet metal 1302 to the first sheet metal 1301, the second sheet metal 1302
The hole 1302A formed at the predetermined position of the first sheet metal 13
01 is arranged slightly below the hole 1301A formed at the predetermined position.

The hole portion 1301 having such a positional relationship
When the drum drive shaft 1305 is inserted into A and 1302A, the drum drive shaft 1305 is attached in a state in which the shaft center is inclined upward from the originally intended position, as shown in FIG. That is, originally, when the shaft center of the drum drive shaft 1305 should be arranged on the alternate long and short dash line A, the axial center of the drum drive shaft 1305 is located at the position of the alternate long and short dash line B due to a defect in the bending accuracy of the second sheet metal 1302. Deviated. Such a drum drive shaft 1
When the photoconductor drum 1309 is attached to the 305,
The constant speed rotational movement of the motor 1303 causes the photosensitive drum 1309
Then, it is transmitted as a non-uniform rotational motion, and uneven rotation, so-called jitter occurs.

In order to prevent such a problem, when manufacturing the second sheet metal 1302, it is necessary to perform a bending process with high accuracy. Since high precision is required for the bending process, there is a problem that the unit price of parts is increased due to an improvement in mold precision and an increase in manufacturing man-hours.

Further, the first sheet metal 1301 and the second sheet metal 130
As a means for determining the distance between the two and the positions of the holes 1301A and 1302A of both, it is conceivable to use the axial length of the reference shaft provided on one of the metal plates. However, even in this case, it is necessary to guarantee the verticality when manufacturing a highly accurate shaft and fixing it to one of the metal plates by crimping or the like. Therefore, the unit price of the component and the number of inspection man-hours may increase, resulting in an increase in product cost.

The present invention has been made in view of the above circumstances, and it is possible to reliably prevent a defect due to the positional relationship between the drum drive shaft and the photosensitive drum while preventing an increase in product cost. An object of the present invention is to provide a method for assembling a photosensitive drum driving device and an electrophotographic recording apparatus.

[0016]

According to the present invention, there is provided a drive shaft which is coaxially engaged with a photosensitive drum, a first flat metal plate having a first hole portion through which the drive shaft is passed, and the first metal plate. A first part when the flat part is connected to the first sheet metal and the flat part is connected to the first sheet metal and the drive system for driving the drive shaft is housed in the recess. A second sheet metal having a second hole for passing a drive shaft on a plane of a recess parallel to the sheet metal, and parallelism between the first sheet metal and the second sheet metal inserted into the first hole and the second hole. In a method of assembling a photosensitive drum driving device, the reference member serving as a reference for forming the first sheet metal and the second sheet metal are first combined to form a reference member in the first hole portion and the second hole portion. Both the first step of inserting and the second sheet metal while maintaining the parallelism between the first sheet metal and the second sheet metal with reference to the reference member. A second step of fixing, a third step of removing the next first hole and the second reference member from the hole, then the first
And a fourth step of inserting the drive shaft into the hole and the second hole.

According to this, the first sheet metal and the second sheet metal are fixed while inserting the reference member into the first hole portion and the second hole portion into which the drum drive shaft is inserted. The coaxiality between the first sheet metal and the second hole is surely maintained, and the parallelism between the first sheet metal and the second sheet metal is secured. A drum drive shaft is inserted into the first hole portion and the second hole portion, and the photosensitive drum is engaged with the drum drive shaft. Therefore, the axial center parallelism between the photoconductor drum and the drum drive shaft is appropriately maintained, and it is possible to reliably prevent problems caused by the positional relationship between the drum drive shaft and the photoconductor drum.

[0018]

BEST MODE FOR CARRYING OUT THE INVENTION A method of assembling a photoconductor drum drive device according to a first aspect of the present invention comprises a drive shaft coaxially engaged with the photoconductor drum, and a first hole through which the drive shaft passes. A first sheet metal having a planar shape, a flat portion connected to the first sheet metal, and a concave portion opened toward the first sheet metal, and a drive system for driving the drive shaft is housed in the concave portion. And a second drive shaft which passes the drive shaft on a flat surface of the recess which is parallel to the first sheet metal when the flat portion is connected to the first sheet metal.
A second sheet metal having a hole; and a reference member which is inserted into the first hole and the second hole and serves as a reference for forming parallelism between the first sheet metal and the second sheet metal. A first step of inserting the reference member into the first hole portion and the second hole portion in a state in which the first sheet metal and the second sheet metal are combined with each other. And a second step of fixing both the first sheet metal and the second sheet metal while maintaining the parallelism with respect to the reference member,
Next, a third step of removing the reference member from the first hole portion and the second hole portion, and a fourth step of inserting the drive shaft into the first hole portion and the second hole portion next. To do.

According to this method, while the reference member is inserted into the first hole portion and the second hole portion, the first sheet metal and the second sheet metal are maintained parallel to each other with the reference member as a reference. Fix it. The first fixed in the state of maintaining parallelism
A drive shaft that is coaxially engaged with the photosensitive drum is inserted into the first hole portion and the second hole portion formed in the sheet metal and the second sheet metal, respectively. According to this, the first sheet metal and the second sheet metal are fixed while inserting the reference shaft into the first hole portion and the second hole portion into which the drum drive shaft is inserted.
The coaxiality with the hole is surely maintained, and the parallelism between the first sheet metal and the second sheet metal is secured. A drum drive shaft is inserted into the first hole portion and the second hole portion, and the photosensitive drum is engaged with the drum drive shaft. For this reason, the axial center parallelism between the photosensitive drum and the drum drive shaft is appropriately maintained, and the uniform rotational movement of the motor is transmitted to the photosensitive drum as non-uniform rotational movement, causing uneven rotation. That situation can be reliably avoided.

Further, when ensuring the parallelism between the first sheet metal and the second sheet metal, the reference member is inserted and fixed in the first hole portion and the second hole portion formed in each. Therefore, it is not necessary to form a reference axis on one of the metal plates, which has a highly accurate length and needs to guarantee the perpendicularity with respect to the metal plate, unlike the related art. Therefore, since it is possible to avoid an increase in the unit price of parts due to an increase in the number of manufacturing steps, it is possible to prevent an increase in product cost.

According to a second aspect of the present invention, there is provided a method for assembling a photosensitive drum driving device, which has a planar shape having a drive shaft coaxially engaged with the photosensitive drum and a first hole portion through which the drive shaft passes. A first sheet metal, a flat portion connected to the first sheet metal, and a recessed portion opening toward the first sheet metal, and a drive system for driving the drive shaft is housed in the recessed portion and the flat portion. A second sheet metal having a second hole portion for passing the drive shaft on a plane of the concave portion which is parallel to the first sheet metal when connecting with the first sheet metal, and the first hole portion and the second hole. A method of assembling a photosensitive drum driving device, comprising: a reference member that is inserted into a portion and serves as a reference for forming parallelism between the first sheet metal and the second sheet metal. The reference member in the first hole portion and the second hole portion in a state of being combined with the second sheet metal. The first step of inserting the first sheet metal and the second sheet metal in the direction from the first sheet metal to the second sheet metal while maintaining the parallelism between the first sheet metal and the second sheet metal with reference to the reference member. A second step of fixing with a screw, a third step of removing the reference member from the first hole portion and the second hole portion, and then a driving shaft in the first hole portion and the second hole portion. And a second step of inserting the first sheet metal into the apparatus main body in a direction from the second sheet metal to the first sheet metal.
And a fifth step of fixing with screws.

According to this method, while the reference member is inserted into the first hole portion and the second hole portion, the first sheet metal and the second sheet metal are maintained parallel to each other with the reference member as a reference. Fix it. The first fixed in the state of maintaining parallelism
A drive shaft that is coaxially engaged with the photosensitive drum is inserted into the first hole portion and the second hole portion formed in the sheet metal and the second sheet metal, respectively. According to this, the first sheet metal and the second sheet metal are fixed while inserting the reference shaft into the first hole portion and the second hole portion into which the drum drive shaft is inserted.
The coaxiality with the hole is surely maintained, and the parallelism between the first sheet metal and the second sheet metal is secured. A drum drive shaft is inserted into the first hole portion and the second hole portion, and the photosensitive drum is engaged with the drum drive shaft. For this reason, the axial center parallelism between the photosensitive drum and the drum drive shaft is appropriately maintained, and the uniform rotational movement of the motor is transmitted to the photosensitive drum as non-uniform rotational movement, causing uneven rotation. That situation can be reliably avoided.

Further, when ensuring the parallelism between the first sheet metal and the second sheet metal, the reference shafts are inserted and fixed in the first hole portion and the second hole portion respectively formed therein. Therefore, it is not necessary to form a reference axis on one of the metal plates, which has a highly accurate length and needs to guarantee the perpendicularity with respect to the metal plate, unlike the related art. Therefore, since it is possible to avoid an increase in the unit price of parts due to an increase in the number of manufacturing steps, it is possible to prevent an increase in product cost.

Further, when fixing the first sheet metal and the second sheet metal, the first sheet metal and the second sheet metal are fixed with the first screw in the direction toward the second sheet metal, while the second sheet metal is fixed with the first sheet metal. When fixing the sheet metal to the main body of the apparatus, it is fixed with the second screw in the direction from the second sheet metal to the first sheet metal. In this way, by making the fixing directions of the first screw and the second screw opposite to each other, it is possible to surely determine which screw fixes which member. Therefore, after the assembly work of the photoconductor drum drive device is completed, when the serviceman removes the photoconductor drum drive device from the apparatus main body for troubleshooting, the first screw is mistakenly removed, and as a result, the drum drive shaft is removed. It is possible to surely avoid a situation in which the parallelism of the shaft center is disturbed.

According to a third aspect of the present invention, in the method of assembling the photosensitive drum driving device according to the second aspect, the screw hole formed in the first sheet metal used for fixing to the second sheet metal is:
It is characterized in that it is larger than the screw hole formed in the second sheet metal.

According to this method, the screw hole for inserting the first screw is inserted after the screw hole formed in the first sheet metal to be inserted first passes through the screw hole formed in the first sheet metal. Is larger than the screw hole formed in the second sheet metal. According to this, even when the screw hole formed in the second sheet metal is slightly displaced from the screw hole formed in the first sheet metal,
If the screw hole formed in the first sheet metal is within the allowable range,
The sheet metal and the second sheet metal can be securely fixed. Accordingly, for example, it is possible to avoid a situation in which the screw cannot be inserted, which may occur when the screw holes formed in the first sheet metal and the second sheet metal have the same size.
The work of fixing the first sheet metal and the second sheet metal can be simplified.

Further, by making the screw holes of the first sheet metal larger than the screw holes of the second sheet metal, for example, when the second sheet metal is produced by bending, the bending accuracy of the concave portion of the second sheet metal is relaxed. Even with this, the second sheet metal and the first sheet metal can be fixed while maintaining the positional relationship between the second hole portion of the second sheet metal and the first hole portion of the first sheet metal, and the bending error of the concave portion of the second sheet metal is Since it can be absorbed by the screw holes of the first sheet metal, it is not necessary to improve the processing accuracy of the second sheet metal, and the cost can be reduced accordingly.

According to a fourth aspect of the present invention, in the method of assembling the photosensitive drum driving device according to the second or third aspect, the inserting direction of the reference member is the same as the fixing direction of the first screw. Is characterized by.

According to this method, when the work of fixing the first screw after inserting the reference member is performed, both works can be performed from the same direction. This eliminates the need to move the position of the operator's body or to move the object of the assembly work. Therefore, it is possible to improve the efficiency of the assembly work of the present photosensitive drum drive device.

According to a fifth aspect of the present invention, there is provided a method of assembling an electrophotographic recording apparatus, comprising a drive shaft which is coaxially engaged with a photosensitive drum, and a planar shape having a first hole through which the drive shaft is passed. 1 sheet metal, a flat portion connected to the first sheet metal, and the first
A recess that opens toward the sheet metal, a drive system that drives the drive shaft is housed in the recess, and the flat portion is parallel to the first sheet metal when the flat portion is connected to the first sheet metal. A second sheet metal having a second hole for passing the drive shaft on the plane of the recess, and parallelism between the first sheet metal and the second sheet metal inserted into the first hole and the second hole. A method of assembling a photosensitive drum driving device, comprising: a reference member that serves as a reference for forming the first sheet metal and the second sheet metal in a state where the first sheet metal and the second sheet metal are combined. A first step of inserting the reference member into the hole, and a second step of fixing the first sheet metal and the second sheet metal while maintaining the parallelism between the first sheet metal and the second sheet metal with reference to the reference member; The first
It comprises a third step of removing the reference member from the hole and the second hole, and a fourth step of inserting the drive shaft into the first hole and the second hole.

According to this method, while the reference member is inserted into the first hole portion and the second hole portion, the first sheet metal and the second sheet metal are kept parallel to each other with reference to the reference member. Fix it. The first fixed in the state of maintaining parallelism
A drive shaft that is coaxially engaged with the photosensitive drum is inserted into the first hole portion and the second hole portion formed in the sheet metal and the second sheet metal, respectively. According to this, the first sheet metal and the second sheet metal are fixed while inserting the reference shaft into the first hole portion and the second hole portion into which the drum drive shaft is inserted.
The coaxiality with the hole is surely maintained, and the parallelism between the first sheet metal and the second sheet metal is secured. A drum drive shaft is inserted into the first hole portion and the second hole portion, and the photosensitive drum is engaged with the drum drive shaft. For this reason, the axial center parallelism between the photosensitive drum and the drum drive shaft is appropriately maintained, and the uniform rotational movement of the motor is transmitted to the photosensitive drum as non-uniform rotational movement, causing uneven rotation. That situation can be reliably avoided.

Further, when securing the parallelism between the first sheet metal and the second sheet metal, the reference shafts are inserted and fixed in the first hole portion and the second hole portion formed in each. Therefore, it is not necessary to form a reference axis on one of the metal plates, which has a highly accurate length and needs to guarantee the perpendicularity with respect to the metal plate, unlike the related art. Therefore, since it is possible to avoid an increase in the unit price of parts due to an increase in the number of manufacturing steps, it is possible to prevent an increase in product cost.

In the method of assembling the electrophotographic recording apparatus according to the sixth aspect of the present invention, the electrophotographic recording apparatus is fixed to the apparatus main body having a drive shaft coaxially engaged with the photosensitive drum and a first hole portion through which the drive shaft passes. Having a flat first sheet metal, a flat portion connected to the first sheet metal, and a recess opening toward the first sheet metal, and a drive system for driving the drive shaft is housed in the recess. And a second sheet metal having a second hole for passing the drive shaft on the plane of the recess which is parallel to the first sheet metal when the flat portion is connected to the first sheet metal, and the first hole portion. And a reference member which is inserted into the second hole and serves as a reference for forming parallelism between the first sheet metal and the second sheet metal. First
A first step of inserting the reference member into the first hole portion and the second hole portion in a state where the sheet metal and the second sheet metal are combined;
Next, with the reference member as a reference, the first sheet metal and the second sheet metal
A second step of fixing both with a first screw in a direction from the first sheet metal to the second sheet metal while maintaining parallelism with the sheet metal; and then from the first hole portion and the second hole portion The third step of removing the reference member, and then the first hole and the second
The fourth step of inserting the drive shaft into the hole, and then the second step
A fifth step of fixing the first sheet metal to the apparatus main body with the second screw in the direction from the sheet metal to the first sheet metal.

According to this method, while the reference member is inserted into the first hole portion and the second hole portion, the first sheet metal and the second sheet metal are kept parallel to each other with the reference member as a reference. Fix it. The first fixed in the state of maintaining parallelism
A drive shaft that is coaxially engaged with the photosensitive drum is inserted into the first hole portion and the second hole portion formed in the sheet metal and the second sheet metal, respectively. According to this, the first sheet metal and the second sheet metal are fixed while inserting the reference shaft into the first hole portion and the second hole portion into which the drum drive shaft is inserted.
The coaxiality with the hole is surely maintained, and the parallelism between the first sheet metal and the second sheet metal is secured. A drum drive shaft is inserted into the first hole portion and the second hole portion, and the photosensitive drum is engaged with the drum drive shaft. For this reason, the axial center parallelism between the photosensitive drum and the drum drive shaft is appropriately maintained, and the uniform rotational movement of the motor is transmitted to the photosensitive drum as non-uniform rotational movement, causing uneven rotation. That situation can be reliably avoided.

Further, when ensuring the parallelism between the first sheet metal and the second sheet metal, the reference shafts are inserted and fixed in the first hole portion and the second hole portion formed in each. Therefore, it is not necessary to form a reference axis on one of the metal plates, which has a highly accurate length and needs to guarantee the perpendicularity with respect to the metal plate, unlike the related art. Therefore, since it is possible to avoid an increase in the unit price of parts due to an increase in the number of manufacturing steps, it is possible to prevent an increase in product cost.

Further, when fixing the first sheet metal and the second sheet metal, both are fixed by the first screw in the direction from the first sheet metal to the second sheet metal, while the first sheet metal is fixed by the first screw. When fixing the sheet metal to the main body of the apparatus, it is fixed with the second screw in the direction from the second sheet metal to the first sheet metal. In this way, by making the fixing directions of the first screw and the second screw opposite to each other, it is possible to surely determine which screw fixes which member. Therefore, it is possible to surely avoid a situation in which another screw is erroneously removed when it is necessary to remove one of the screws for some reason after the assembly work of the photosensitive drum drive device is completed.

A seventh aspect of the present invention is the method of assembling the electrophotographic recording apparatus according to the sixth aspect, wherein the screw holes formed in the first sheet metal used for fixing the second sheet metal are It is characterized in that it is larger than the screw hole formed in the two sheet metal.

According to this method, the screw hole for inserting the first screw is inserted after the screw hole formed in the first sheet metal to be inserted first passes through the screw hole formed in the first sheet metal. Is larger than the screw hole formed in the second sheet metal. According to this, even when the screw hole formed in the second sheet metal is slightly displaced from the screw hole formed in the first sheet metal,
If the screw hole formed in the first sheet metal is within the allowable range,
The sheet metal and the second sheet metal can be securely fixed. Accordingly, for example, it is possible to avoid a situation in which the screw cannot be inserted, which may occur when the screw holes formed in the first sheet metal and the second sheet metal have the same size.
The work of fixing the first sheet metal and the second sheet metal can be simplified.

According to an eighth aspect of the present invention, in the method of assembling the electrophotographic recording apparatus according to the sixth aspect, the inserting direction of the reference member is the same as the fixing direction of the first screw. To do.

According to this method, when the work of fixing the first screw after inserting the reference member is performed, both works can be performed from the same direction. This eliminates the need to move the position of the operator's body or to move the object of the assembly work. Therefore, it is possible to improve the efficiency of the assembly work of the present photosensitive drum drive device.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

FIG. 1 shows an electrophotographic recording apparatus 100 to which a photosensitive drum driving device according to an embodiment of the present invention is applied.
2 is a schematic configuration diagram of FIG. As shown in FIG. 1, the electrophotographic recording apparatus 100 is provided with a reading unit 101 for reading a document on an upper part thereof, and a main body unit 102 for performing paper feeding, transfer, recording, and fixing processes below the reading unit 101.

A paper feed cassette 103 is installed at the bottom of the main unit 102. The uppermost sheet from the bundle of sheets set in the sheet cassette 103 is the pickup roller 1.
It is taken out by 04.

The paper taken out from the paper feed cassette 103 is sent by the paper feed roller 105 to the paper path 106 formed from the bottom of the main body unit 102 upward. The paper path 106 includes a plurality of carrying rollers 10 as a paper carrying means in the paper carrying device according to the present invention.
7, 108 and 109 are arranged. Conveyor roller 1
Reference numerals 07, 108 and 109 denote main body unit 1 not shown.
The open / close cover 02 is replaceable.

In this embodiment, the case where the upper and lower three conveying rollers are arranged is shown, but the present invention is not limited to this and can be applied regardless of the number of conveying rollers. For example, the present invention can be applied to the case where there is a single transport roller.

In the present embodiment, the transport rollers 107, 108 and 109 arranged on the paper path 106 will be described, but the present invention is not limited to this. As long as it is a conveyance roller that conveys a sheet and needs to be replaced, the conveyance roller at any position of the electrophotographic recording apparatus 100 can be applied.

The sheet conveyed by the conveying roller 109 arranged at the uppermost position is conveyed to the registration roller 111 by the conveying roller 110. Registration roller 111
A photosensitive drum 112 that rotates in the direction of the arrow in the figure is arranged at the destination of the sheet conveyed by. Photoconductor drum 112
Is rotatably supported by the side surface of the photosensitive drum driving device according to the present embodiment.

Above the photoconductor drum 112, an LSU (Laser) for forming a latent image on the surface of the photoconductor drum 112.
Scan Unit) 113 is arranged. Photoconductor drum 1
A developing device 114 for adhering a developing material (toner) to the latent image formed on the image forming apparatus 12 is disposed adjacent to the photosensitive drum 112. The developer is agitated inside the developing device 114.
It is provided with a stirring roller for conveying and a developing roller for adhering a developing material to the photosensitive drum 112.

Below the photoconductor drum 112, a transfer device 115 for transferring the image formed by the developer adhering to the photoconductor drum 112 onto the conveyed paper is installed. The registration roller 111 controls the position adjustment between the image on the photosensitive drum 112 and the recording area of the paper.

Photosensitive drum 112 on which the image has been transferred
Unit 116 for cleaning the surface of
Are arranged adjacent to the photosensitive drum 112. The sheet on which the image is transferred is further conveyed by the conveyor belt 117. The fixing unit 1 is provided at the conveyance destination of the conveyance belt 117.
18 are arranged.

The fixing unit 118 includes a fixing roller 119.
And the pressure roller 12 arranged to face the fixing roller 119.
0, and a cleaning roller (not shown) for applying oil to enhance the peeling property of the toner remaining on the fixing roller 119. The fixing roller 119 applies heat to the recording surface of the paper, and the pressure roller 120 fixes the paper to the fixing roller 11.
By pressing between 9 and 9, the image is fixed on the paper.

The sheet discharged from the fixing unit 118 is discharged to the outside of the main body unit 102 by the discharge roller 121. The sheet discharged from the main body unit 102 is received on the sheet discharge tray 122.

A switching guide 124 is provided between the fixing unit 118 and the discharge roller 121 to switch between discharging the paper to the outside of the main body unit 102 and sending it to the double-sided path 123 for double-sided recording. The double-sided path 123 is formed downward from the vicinity of the switching guide 124, and is formed substantially horizontally in the middle thereof.

The sheet sent to the double-sided path 123 is temporarily drawn by the reverse roller 125 into the reverse path 126 formed on the extension of the downwardly formed portion 123A of the double-sided path 123. When the sheet is drawn into the reversing path 126, the reversing roller 125 reverses the sheet, and the part 123 of the double-sided path 123 is formed in a substantially horizontal direction.
Send to B. At this point, the front and back of the paper are reversed.

Double-sided path 123B formed in a substantially horizontal direction
The sheet fed into the sheet is conveyed by the conveying rollers 127, 128 and 129 formed on the double-sided path 123B. The double-sided path 123B is connected to the paper path 106 below the transport roller 110. Conveyor rollers 127, 12
The paper that has been conveyed to the paper path 106 by the double-sided path 123B by 8 and 129 is again conveyed to the photoconductor drum 11.
The image is formed on the back side of the sheet 2, which is then fed below.

A manual feed tray 1 for realizing paper feeding other than the paper feeding from the paper feeding cassette 103 on the side surface of the main body unit 102.
30 are provided. The uppermost sheet of the sheet bundle placed on the manual feed tray 130 is taken in by the pickup roller 131 and passed to the registration roller 111 by the conveyance roller 132.

FIG. 2 shows a sectional view of the photosensitive drum driving device according to the present embodiment after assembly, and FIG. 3 shows an exploded perspective view of the photosensitive drum driving device according to the present embodiment.

As shown in FIGS. 2 and 3, the photosensitive drum driving device 200 according to the present embodiment has the photosensitive drum 1 as shown in FIG.
It is installed on the opposite side of the photoconductor drum 112 with the inner housing 201 of the main body unit 102, which is arranged opposite to the side surface of the twelve 12, sandwiching the inner housing 201.

The present photosensitive drum driving device 200 has a shape in which a space for accommodating a motor described later is secured.
The drum drive shaft 202 is supported near its center. When the present photosensitive drum driving device 200 is installed, the drum drive shaft 202 passes through a hole 201A formed at a predetermined position of the inner casing 201 and engages with the side surface of the photosensitive drum 112. When properly engaged, the drum drive shaft 202
Engages with the photoconductor drum 112 coaxially and rotates integrally with the photoconductor drum 112.

In the present photosensitive drum driving device 200, a second sheet metal 204 having a shape opened to the first sheet metal 203 by a bending process or the like is connected to a first sheet metal 203 having a planar shape which is superposed on the inner casing 201. By doing so, a certain space is provided inside. The second sheet metal 204 is the first
The first sheet metal 203 is formed by the flat surface portion 211 parallel to the sheet metal 203.
Connected with. This connected first sheet metal 203 and second
The sheet metal 204 (hereinafter, referred to as “a pair of sheet metals”) is formed from the first sheet metal 203 to the second sheet metal 204 with respect to the inner casing 201.
It is fixed by a screw 206 from the side opposite to the screw 205 fixed in the direction toward. In the present embodiment,
Self-tapping type screws are used for the screws 205 and 206.

In the space inside the photosensitive drum driving device 200, the motor 2 as a drive source of the photosensitive drum 112 is provided.
07 is stored. The motor 207 uses the second sheet metal 20.
It is fixed to a predetermined position on the side surface of No. 4 above the drum drive shaft 202. The drive shaft of the motor 207 is
It passes through a hole 204A formed at a predetermined position of the second sheet metal 204 and projects to the outside of the second sheet metal 204.

The peripheral surface of the drive gear 208 attached to the end of the drum drive shaft 202 meshes with the drive shaft of the motor 207. As a result, the power of the motor 207 becomes
8 is transmitted to the drum drive shaft 202.

The drum drive shaft 202 is located at a position corresponding to the hole 201A formed in the inner casing 201, and is the first
The hole 203A formed in the sheet metal 203 and the second sheet metal 20.
It penetrates through the hole portion 204B formed in No. 4 (see FIG. 3). The drum drive shaft 202 has a hole 203A and a hole 2
Bearings 209 and 2 fitted in 04B respectively
It is rotatably held by 10.

Next, an assembling process of the photoconductor drum driving device 200 according to the present embodiment having the above-mentioned structure will be described.

First, as shown in FIG. 4, the second sheet metal 204 having the motor 207 fixed at a predetermined position and manufactured by press working or the like is aligned with the predetermined position of the first sheet metal 203. At this time, the alignment of both is performed by the holes 203A and 20A formed in the first sheet metal 203 and the second sheet metal 204, respectively.
4B is roughly aligned.

Next, as shown in FIG. 5, the first sheet metal 203
And the second sheet metal 204 together, the first sheet metal 203
And holes 203 formed in each of the second sheet metal 204
The reference shaft 501 is inserted from the first sheet metal 203 side so as to penetrate A and 204B.

Here, the reference shaft 501 is the first sheet metal 203.
And the second sheet metal 204 is a reference axis of parallelism. The reference shaft 501 includes the first sheet metal 203 and the second sheet metal 20.
4 has a shape that matches the shape of the holes 203A and 204B formed in each of the four. In the present embodiment, the holes 203A and 204B have circular shapes of the same size,
The reference shaft 501 has a cylindrical shape having the same thickness.
In addition, the reference shaft 501 has a circumferential surface with holes 203A and 203A.
It matches the circular shape of 04B.

It should be noted that the reference shaft 501 is provided with a member 502 for restricting the insertion of the reference shaft 501 before a certain position during the insertion work into the pair of sheet metals. This member 50
2 may be integrally formed with the reference shaft 501 or may be separately attached.

By penetrating the reference shaft 501 into the holes 203A and 204B, the first sheet metal 203 and the second sheet metal 204 can be aligned in a fixed positional relationship. Further, the holes 203A and 204 having the same shape as the peripheral surface
Since it is inserted in B, the reference shaft 501 cannot be inserted unless it is inserted perpendicularly to them. Therefore, when the reference shaft 501 is inserted, the holes 203A and 20
The parallelism of the 1st sheet metal 203 and the 2nd sheet metal 204 in which 4B was formed will be ensured.

As shown in FIG. 6, the first sheet metal 203 and the second sheet metal 204 thus aligned in a fixed positional relationship are screwed 205 in the direction from the first sheet metal 203 to the second sheet metal 204. To conclude. When aligned by the reference shaft 501 in a fixed positional relationship, the hole 203B into which the screw 205 formed in the first sheet metal 203 is inserted and the second sheet metal 204.
The hole portion 204C into which the screw 205 formed in is inserted is arranged at a corresponding position.

In the present embodiment, when the screw 205 is fixed after inserting the reference shaft 501,
Both work is done from the same direction. This eliminates the need to move the position of the operator's body or to move the object of the assembly work. Therefore, it is possible to improve the efficiency of the assembly work of the present photosensitive drum drive device.

FIG. 7 shows an enlarged view of the fastening portion of the screw 205. As shown in FIG. 7, the hole 203 </ b> B into which the screw 205 formed in the first sheet metal 203 is inserted is the second sheet metal 204.
Has a diameter larger than that of the hole portion 204C into which the screw 205 formed in is inserted. The diameter of the hole 203B is
It has a smaller diameter than the umbrella portion of the screw 205. According to this, even if the hole portion 204C formed in the second sheet metal 204 is slightly deviated from the hole portion 203B formed in the first sheet metal 203, the hole portion 203 formed in the first sheet metal 203.
If the allowable range is B, the first sheet metal 203 and the second sheet metal 20
4 and 4 can be fixed reliably. Accordingly, for example, it is possible to avoid a situation in which the screw 205 cannot be inserted, which may occur when the holes formed in the first sheet metal 203 and the second sheet metal 204 have the same size. The work of fixing the first sheet metal 203 and the second sheet metal 204 can be simplified.

If the hole 203B for inserting the screw 205 and the hole 204C are set to have the same size, even if the first sheet metal 203 and the second sheet metal 204 are slightly misaligned, they are inserted in the hole 203B. It may happen that the screws 205 do not match the positions of the holes 204C and the screws 205 cannot be inserted into these holes. However, according to the present embodiment, if the hole portion 204C is inside the hole portion 203B, the screw 205 can be inserted into the hole portion 204C. It can be avoided.

Further, by making the hole portion 203B of the first sheet metal 203 larger than the hole portion 204C of the second sheet metal 204, for example, when the second sheet metal 204 is manufactured by bending, the second sheet metal 204 Even if the bending accuracy is relaxed, the second sheet metal 204 and the first sheet metal 203 are maintained while maintaining the positional relationship between the hole portion 204B of the second sheet metal 204 and the hole portion 203A of the first sheet metal 204 into which the drum drive shaft 202 is inserted. And can be fixed,
Since the bending error of the recess of the second sheet metal 204 can be absorbed by the hole 203B of the first sheet metal 203, it is not necessary to increase the processing accuracy of the second sheet metal 204, and the cost can be reduced accordingly.

When the positional relationship between the first sheet metal 203 and the second sheet metal 204 is fixed at the time when the pair of sheet metals are fastened with the screws 205, the first sheet metal 203 and the second sheet metal 204 are fixed as shown in FIG. The reference shaft 501 that has penetrated is pulled out.
Even when the reference shaft 501 is pulled out, the positional relationship between the first sheet metal 203 and the second sheet metal 204 is fixed, so that the parallelism between the first sheet metal 203 and the second sheet metal 204 is maintained.

After pulling out the reference shaft 501, as shown in FIG. 9, the drum drive shaft 202 having the drive gear 208 attached to one end thereof is provided with the hole 204 formed in the second sheet metal 204.
Insert from B. At that time, the drum drive shaft 202 is rotatably held by the bearing 210 and the bearing 209 fitted in the holes 203A and 204B, respectively.

The bearing 210 is the drum drive shaft 202.
Is attached to the hole 204 </ b> B according to the insertion of the drum drive shaft 202. On the other hand, the bearing 209 is fitted into the hole 203A from the direction opposite to the insertion direction of the drum drive shaft 202.

When the drum drive shaft 202 is inserted to a predetermined position, the peripheral surface of the drive gear 208 meshes with the drive shaft of the motor 207, as shown in FIG. In this way, the drive unit of the present photosensitive drum drive device is configured. Next, the drive unit is attached to the internal housing 201.

At the time of mounting, one end of the drum drive shaft 202 is inserted into the hole portion 201A formed in the inner casing 201. Then, the bearing 209 holding the drum drive shaft 202 is aligned so as to be housed in the hole 201A. Then, in a state where the first sheet metal 203 and the inner casing 201 are combined, as shown in FIG. 10, the drive unit is fastened with screws 206 from the first sheet metal 203 side.

Thus, the first sheet metal 203 and the second sheet metal 20 are
When fixing 4 and 4, the first sheet metal 203 to the second sheet metal 204
While fixing them with screws 205 in the direction toward
The first metal plate 203 to which the metal plate 204 is fixed is attached to the internal housing 20.
When fixing to No. 1, the screws 206 are fixed in the direction from the second sheet metal 204 to the first sheet metal 203. By setting the fixing directions of the screws 205 and 206 to be opposite to each other, it is possible to reliably determine which screw fixes which member. Therefore, it is possible to surely avoid a situation in which another screw is erroneously removed when it is necessary to remove one of the screws for some reason after the assembly work of the photosensitive drum drive device is completed.

FIG. 11 shows an enlarged view around the fastening portion of the screw 206. As shown in FIG. 11, the hole portion 203 </ b> C in which the screw 206 formed in the first sheet metal 203 is inserted is a hole portion 20 in which the screw 206 formed in the internal housing 201 is inserted.
It has a diameter larger than 1B. The hole 203C
Has a smaller diameter than the umbrella portion of the screw 206. The size relationship between the hole 203C and the hole 201B is similar to the size relationship between the hole 203B into which the screw 205 is inserted and the hole 204C.

The inner casing 201 is formed with a hole 201C for accommodating the umbrella portion of the screw 205 protruding from the first sheet metal 203. Even when the first sheet metal 203 is fitted to the inner casing 201, the umbrella portion of the screw 205 has the hole portion 20.
Go into 1C. Therefore, the umbrella portion of the screw 205 protruding from the first sheet metal 203 does not hinder the work of attaching the drive unit.

When the drive unit is fixed to the internal casing 201 with the screws 206, finally, as shown in FIG. 12, the photosensitive drum 112 is engaged with the drum drive shaft 202 protruding inside the internal casing 201. To meet. In this way, the assembly process of the photosensitive drum driving device 200 is completed.

As described above, according to the method of assembling the photosensitive drum driving device of the present embodiment, the reference member is the first hole and the second member.
With this reference member as a reference, the first
The two are fixed while maintaining the parallelism between the sheet metal and the second sheet metal. Further, a first hole portion and a second hole portion formed in each of the first sheet metal and the second sheet metal fixed while maintaining the parallelism.
A drive shaft that is coaxially engaged with the photosensitive drum is inserted into the hole. According to this, the first drum drive shaft is inserted
Since the first sheet metal and the second sheet metal are fixed while inserting the reference shaft into the hole portion and the second hole portion, the coaxiality between the first hole portion and the second hole portion is surely maintained, and 1st sheet metal and 2nd
The parallelism with the sheet metal is secured. These first hole and second
The drum drive shaft is inserted into the hole, and the photosensitive drum is engaged with the drum drive shaft. For this reason, the axial center parallelism between the photosensitive drum and the drum drive shaft is appropriately maintained, and the uniform rotational movement of the motor is transmitted to the photosensitive drum as non-uniform rotational movement, causing uneven rotation. That situation can be reliably avoided.

Further, when ensuring the parallelism between the first sheet metal and the second sheet metal, the reference member is fixed while being inserted into the first hole portion and the second hole portion formed respectively. Therefore, it is not necessary to form a reference axis on one of the metal plates, which has a highly accurate length and needs to guarantee the perpendicularity with respect to the metal plate, unlike the related art. Therefore, since it is possible to avoid an increase in the unit price of parts due to an increase in the number of manufacturing steps, it is possible to prevent an increase in product cost.

[0086]

As described above, according to the present invention,
While preventing an increase in product cost, it is possible to reliably prevent a defect due to the positional relationship between the drum drive shaft and the photosensitive drum.

[Brief description of drawings]

FIG. 1 is a schematic configuration diagram of an electrophotographic recording device to which a photosensitive drum driving device according to an embodiment of the present invention is applied.

FIG. 2 is a cross-sectional view of the photosensitive drum driving device according to the above embodiment after assembly.

FIG. 3 is an exploded perspective view of the photoconductor drum driving device according to the above embodiment.

FIG. 4 is a cross-sectional view of an assembly process of the photosensitive drum driving device according to the above embodiment.

FIG. 5 is a sectional view of an assembly process of the photosensitive drum driving device according to the above embodiment.

FIG. 6 is a cross-sectional view of an assembly process of the photosensitive drum driving device according to the above embodiment.

FIG. 7 is an enlarged view of a fastening portion of a screw that fastens the first sheet metal to the second sheet metal in the photosensitive drum driving device according to the above embodiment.

FIG. 8 is a sectional view of an assembly process of the photosensitive drum driving device according to the above embodiment.

FIG. 9 is a cross-sectional view of an assembly process of the photosensitive drum driving device according to the above embodiment.

FIG. 10 is a sectional view of an assembly process of the photosensitive drum driving device according to the above embodiment.

FIG. 11 is an enlarged view of a portion around the fastening portion of a screw that fastens the first sheet metal to the internal housing in the photosensitive drum driving device according to the above-described embodiment.

FIG. 12 is a cross-sectional view of an assembly process of the photosensitive drum drive device according to the above embodiment.

FIG. 13 is a cross-sectional view showing the configuration of a conventional photosensitive drum driving device.

FIG. 14 is a sectional view of an assembly process of a conventional photosensitive drum driving device.

FIG. 15 is a sectional view of an assembling process of a conventional photosensitive drum driving device.

FIG. 16 is a sectional view of an assembly process of a conventional photosensitive drum driving device.

FIG. 17 is a sectional view of an assembly process of a conventional photosensitive drum driving device.

FIG. 18 is a sectional view of an assembly process of a conventional photosensitive drum drive device.

FIG. 19 shows a second example of the conventional photosensitive drum driving device.
The figure showing a state in which the sheet metal is fixed to the first sheet metal without being appropriately bent.

FIG. 20 is an enlarged view of the inserted drum drive shaft and its periphery in the state shown in FIG. 19;

[Explanation of symbols]

100 Electrophotographic recording device 101 reading unit 102 Main unit 107-109 Conveyor rollers 201 Internal housing 202 drum drive shaft 203 First sheet metal 204 second sheet metal 205,206 screw 207 motor 208 drive gear 209, 210 bearings 501 reference axis

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Kunihiro Tanaka             2-3-8 Shimo-Meguro, Meguro-ku, Tokyo Matsushita             Dentsu System Co., Ltd. (72) Inventor Masahiro Takizawa             2-3-8 Shimo-Meguro, Meguro-ku, Tokyo Matsushita             Dentsu System Co., Ltd. F term (reference) 2H035 CA07 CB01 CB04 CD01 CD05                       CG03                 2H071 CA02 CA05 EA06                 3J103 AA02 BA43 CA62 EA20 FA17                       FA18 GA57 GA58 GA60

Claims (8)

[Claims] 1. A first planar surface having a drive shaft coaxially engaged with the photosensitive drum and a first hole through which the drive shaft passes.
A sheet metal, a flat portion connected to the first sheet metal, and a concave portion opened toward the first sheet metal, and a drive system for driving the drive shaft is housed in the concave portion, and the flat portion is A second sheet metal having a second hole for passing the drive shaft on a plane of the recess which is parallel to the first sheet metal when connected to the first sheet metal; and the first hole and the second hole. A method of assembling a photosensitive drum driving device, comprising: a reference member that is inserted and serves as a reference for forming parallelism between the first sheet metal and the second sheet metal. A first step of inserting the reference member into the first hole portion and the second hole portion in a state where the two sheet metals are combined, and then the first sheet metal and the second sheet metal with reference to the reference member. A second step of fixing the two while maintaining parallelism, and then the first hole and the second hole And a fourth step of inserting the drive shaft into the first hole portion and the second hole portion, and a third step of removing the reference member from the portion. Assembly method. 2. A first planar shape having a drive shaft coaxially engaged with the photosensitive drum, and a first hole through which the drive shaft passes.
A sheet metal, a flat portion connected to the first sheet metal, and a concave portion opened toward the first sheet metal, and a drive system for driving the drive shaft is housed in the concave portion, and the flat portion is A second sheet metal having a second hole for passing the drive shaft on a plane of the recess which is parallel to the first sheet metal when connected to the first sheet metal; and the first hole and the second hole. A method of assembling a photosensitive drum driving device, comprising: a reference member that is inserted and serves as a reference for forming parallelism between the first sheet metal and the second sheet metal. A first step of inserting the reference member into the first hole portion and the second hole portion in a state where the two sheet metals are combined, and then the first sheet metal and the second sheet metal with reference to the reference member. While maintaining the parallelism, the first metal plate and the second metal plate are moved in the direction from the first metal plate to the second metal plate. The second step of fixing the drive shaft to the first hole and the second hole, and the third step of removing the reference member from the first hole and the second hole. A fourth step of inserting,
Next, a fifth step of fixing the first sheet metal to the apparatus main body with a second screw in the direction from the second sheet metal to the first sheet metal,
A method for assembling a photosensitive drum driving device, comprising: 3. The first member used for fixing to the second sheet metal.
3. The method of assembling the photosensitive drum driving device according to claim 2, wherein the screw hole formed in the sheet metal is larger than the screw hole formed in the second sheet metal. 4. The method of assembling the photosensitive drum driving device according to claim 2, wherein the inserting direction of the reference member is the same as the fixing direction of the first screw. 5. A first planar shape having a drive shaft coaxially engaged with the photosensitive drum, and a first hole through which the drive shaft passes.
A sheet metal, a flat portion connected to the first sheet metal, and a concave portion opened toward the first sheet metal, and a drive system for driving the drive shaft is housed in the concave portion, and the flat portion is A second sheet metal having a second hole for passing the drive shaft on a plane of the recess which is parallel to the first sheet metal when connected to the first sheet metal; and the first hole and the second hole. A method of assembling a photosensitive drum driving device, comprising: a reference member that is inserted and serves as a reference for forming parallelism between the first sheet metal and the second sheet metal. A first step of inserting the reference member into the first hole portion and the second hole portion in a state where the two sheet metals are combined, and then the first sheet metal and the second sheet metal with reference to the reference member. A second step of fixing the two while maintaining parallelism, and then the first hole and the second hole Assembly of an electrophotographic recording apparatus, comprising: a third step of removing the reference member from the portion, and a fourth step of inserting the drive shaft into the first hole portion and the second hole portion. Method. 6. A drive shaft which is coaxially engaged with the photosensitive drum, a planar first sheet metal fixed to an apparatus main body having a first hole portion through which the drive shaft is passed, and a connection with the first sheet metal. Has a flat surface portion and a recess opening toward the first sheet metal, the drive system for driving the drive shaft is housed inside the recess portion, and the flat surface portion is connected to the first sheet metal when the drive system is connected. A second sheet metal having a second hole for passing the drive shaft on a plane of the recess parallel to the first sheet metal; the first sheet metal and the first sheet metal inserted into the first hole and the second hole; A method of assembling an electrophotographic recording apparatus, comprising: a reference member serving as a reference for forming parallelism between two sheet metals, wherein the first sheet metal and the second sheet metal are first combined together. The first step of inserting the reference member into the one hole portion and the second hole portion, and then the reference member As a quasi-second, a second step of fixing the first sheet metal and the second sheet metal with a first screw in a direction from the first sheet metal to the second sheet metal while maintaining parallelism, and then the second step. A third step of removing the reference member from the first hole and the second hole, and a fourth step of inserting the drive shaft into the first hole and the second hole,
Next, a fifth step of fixing the first sheet metal to the apparatus main body with a second screw in the direction from the second sheet metal to the first sheet metal,
A method for assembling an electrophotographic recording apparatus, comprising: 7. The first used for fixing to the second sheet metal
7. The method of assembling an electrophotographic recording apparatus according to claim 6, wherein the screw hole formed in the sheet metal is larger than the screw hole formed in the second sheet metal. 8. The method of assembling an electrophotographic recording apparatus according to claim 6, wherein the inserting direction of the reference member is the same as the fixing direction of the first screw.