JPH1039713A - Recorder - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a recorder which eliminates irregularity in the rotation of a photoreceptor drum so as to stably obtain a high quality image. SOLUTION: In the recorder while records by rotating and driving the photoreceptor drum 501, the photoreceptor drum 501 can be attached/detached by the rotating force of an ultrasonic motor (motor for rotating and driving the photoreceptive drum) 1001. Because the rotary shaft 1005 of the ultrasonic motor 1001 and the photoreceptor drum are satisfactorily connected without play, the high quality image with very little color-slippage is obtained in the multicolor recorder equipped with the plurality of photoreceptive drums, and the high quality image free of image expansion and contraction in the rotating direction of the photoreceptor drum is obtained in the recorder equipped with the single photoreceptor drum.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] 1. Field of the Invention [0002] The present invention relates to a recording apparatus for recording by rotating a photosensitive drum.

[0002]

2. Description of the Related Art Heretofore, in this type of recording apparatus, the mounting and dismounting of the photosensitive drum has been performed manually. In order to facilitate the attachment and detachment of the photosensitive drum in such a recording apparatus, it is necessary to couple the drive shaft of the photosensitive drum drive motor and the photosensitive drum with a coupling or the like.

[0003]

However, if the photosensitive drum and the drive shaft are coupled by a coupling or the like in order to facilitate the mounting and dismounting of the photosensitive drum, unevenness in rotation of the photosensitive drum due to looseness of the coupling portion or the like is caused. This has been a factor that hinders improvement in image quality.

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and an object of the present invention is to provide a recording apparatus capable of eliminating rotation unevenness of a photosensitive drum and stably obtaining a high-quality image. is there.

[0005]

According to a first aspect of the present invention, there is provided a recording apparatus for recording by rotating a photosensitive drum, wherein the photosensitive drum is rotated by a rotational force of a motor for rotating the photosensitive drum. The drum is detachable.

According to a second aspect of the present invention, in the first aspect of the present invention, when the photosensitive drum is mounted, the photosensitive drum rotation drive motor rotates in the same direction as that during image recording.

According to a third aspect of the present invention, in the first aspect of the invention, when the photosensitive drum is detached, the photosensitive drum rotation driving motor rotates in a direction opposite to that during image recording.

According to a fourth aspect of the present invention, in the first aspect of the present invention, there is provided a photosensitive drum rotation preventing means for preventing the relative rotation between the rotating shaft of the photosensitive drum rotation driving motor and the photosensitive drum when the photosensitive drum is attached or detached. It is characterized by having.

According to a fifth aspect of the present invention, in the fourth aspect of the invention, a part of the photosensitive drum rotation preventing means is provided on a support shaft opposite to a rotation shaft of the photosensitive drum rotation drive motor. It is characterized by.

According to a sixth aspect of the present invention, in the fifth aspect of the present invention, the photosensitive drum rotation preventing means includes a one-way or two-way portion provided on the support shaft and one provided on the photosensitive drum side. It is characterized in that it is formed with a hole, a two-way hole or a substantially rectangular hole.

According to a seventh aspect of the present invention, in the fifth aspect of the invention, the photosensitive drum rotation preventing means is constituted by a clutch provided on the support shaft.

According to an eighth aspect of the present invention, in the invention of the fourth to sixth or seventh aspects, even when the photosensitive drum is removed, the same photosensitive drum rotation preventing means as when the photosensitive drum is mounted is used.

According to a ninth aspect of the present invention, in the first to seventh or eighth aspects, the photosensitive drum rotation driving motor is an ultrasonic motor.

According to a tenth aspect of the present invention, in the first to seventh or eighth aspects, the photosensitive drum rotation driving motor is a stepping motor.

An eleventh aspect of the present invention is characterized in that, in the first to ninth or tenth aspects, the same number of photosensitive drums and photosensitive drum rotation driving motors are provided.

The twelfth aspect of the present invention is the first to tenth aspects.
Alternatively, in the invention according to the eleventh aspect, a plurality of photosensitive drums are provided.

Therefore, according to the present invention, the motor rotating shaft and the photosensitive drum are satisfactorily connected to each other without play using the rotational force of the motor. , A high-quality image is obtained, and in a recording apparatus having a single photosensitive drum, a high-quality image without image expansion and contraction in the photosensitive drum rotation direction can be obtained.

[0018]

Embodiments of the present invention will be described below with reference to the accompanying drawings.

First Embodiment First, the schematic structure and operation of a multicolor printing apparatus according to the present invention will be described with reference to FIG.

FIG. 3 is a sectional view of a main part of the multicolor recording apparatus.
In the multicolor recording apparatus, the transfer paper P is transported in the direction of the arrow shown in the figure. The transfer paper P is transported by rollers TR1 and TR1.
The transfer belt TF1 is satisfactorily guided on an endless transfer belt TF1 wound around TR2.
1 and the transfer blade T1 are transported to a black transfer position set so as to be held therebetween.

Around the photosensitive drum 501, a charging means C1, an exposing means E1, a developing means D1, and a cleaning means CB1 are provided, respectively. The photosensitive drum 501 rotates in the direction of the arrow shown in FIG. It is uniformly charged. When the uniformly charged photosensitive drum 501 receives the exposure from the exposing means E1, an electrostatic latent image is formed on the photosensitive drum 501, and the electrostatic latent image is formed on the developing sleeve of the developing means D1. The toner image is developed by the black toner carried on S1 and visualized as a black toner image. This black toner image is transferred onto the transfer paper P by the action of the transfer blade T1. The black toner image remaining on the photosensitive drum 501 without being transferred is removed and collected by the cleaning unit CB1, and the photosensitive drum 501 whose surface is cleaned is repeatedly subjected to an image forming process.

The transfer paper P to which the black toner image has been transferred is conveyed to the cyan transfer position set so as to be held between the photosensitive drum 502 and the transfer blade T2 as the next recording means. You. At this time, the charging means C
2, the photosensitive drum 5 by the exposing means E2 and the developing means D2.
02, a cyan toner image is formed, and this cyan toner image is transferred onto the transfer paper P by the action of the transfer blade T2.

Thereafter, the transfer paper P is similarly transferred to the photosensitive drum 5
No. 03 and the transfer blade T3 are conveyed to a magenta transfer position set so as to be held therebetween and receive the transfer of the magenta toner image formed on the photosensitive drum 503, and finally held between the photosensitive drum 504 and the transfer blade T4. The photosensitive drum 504 is transported to the yellow transfer position set to
The yellow toner image formed thereon is transferred. still,
In FIG. 3, C3 and C4 are charging means, E3 and E4 are exposure means, D3 and D4 are development means, S2, S3 and S4 are development sleeves, and CB2, CB3 and CB4 are cleaning means.

The multi-color toner image is transferred onto the transfer paper P through the above process, and the transfer paper P having received the transfer of the multi-color toner image is conveyed to the fixing means F1 and is subjected to heat and pressure to generate the multi-color toner image. The image is fixed.

In a recording apparatus using a single photosensitive drum, a desired single-color image can be obtained by using a single recording unit. However, the recording process is the same as that for obtaining a multicolor image. The description of them is omitted.

Here, the structure of the drive mechanism of the photosensitive drum 501 and the mounting / detaching structure will be described with reference to FIG. Note that the configuration and the attachment / detachment structure of the drive mechanisms of the other photosensitive drums 502, 503, and 504 are the same, and illustration and description thereof will be omitted.

FIG. 1 is a sectional view showing the structure of a drive mechanism for the photosensitive drum 501 and the mounting / removing structure.
Is rotationally driven by an ultrasonic motor 1001 fixed to the side plate 1002, and the rotating shaft 1 of the ultrasonic motor 1001
005 is detachable.

That is, a flange 501A is fitted to one end of the photosensitive drum 501, and a circular hole 501a and a female screw portion 501b having a larger diameter than the circular hole 501a are formed at the center of the flange 501A. I have.

On the other hand, the rotating shaft 10 of the ultrasonic motor 1001
05 has a large diameter part 1005a and a male screw part 1005b
The female screw portion 5 formed on the flange 501A of the photosensitive drum 501 is formed on the male screw portion 1005b.
01b is screwed.

When the photosensitive drum 501 is mounted (during wearing), the flange 501 of the photosensitive drum 501 is mounted.
A into the circular hole 501a formed in the ultrasonic motor 100
1 through the rotary shaft 1005 of FIG.
, And insert the female screw portion 501 b into the rotating shaft 5.
001 is fitted into the male screw part 5001b. And
In this state, the ultrasonic motor 1001 is driven to
05 is rotated in the same direction as the rotation direction at the time of recording, the male screw portion 5001b of the rotating shaft 5001 and the photosensitive drum 50 are rotated.
The female drum portion 501b formed on the first flange 501A is screwed into the photosensitive drum 501, and the photosensitive drum 501 is in the solid line direction in FIG. Insert direction). When the movement of the photosensitive drum 501 stops, the mounting of the photosensitive drum 501 is completed.

Therefore, the photosensitive drum 501 is connected to the flange 50
The outer end surface of the rotary shaft 500A contacts the end surface N of the large-diameter portion 5001a of the rotary shaft 5001 so that the axial positioning is accurately performed, and the rotary shaft is formed on the inner peripheral surface K of the circular hole 501a formed in the flange 501A. By inserting the 1005, positioning in the radial direction (that is, centering) is performed with high accuracy.

Next, when the photosensitive drum 501 in the mounted state is to be removed (during removal), the ultrasonic motor 1001 is driven to rotate the rotating shaft 1005 in the reverse direction.
Since the female screw portion 501b formed on the first flange 501A and the male screw portion 1005b of the rotating shaft 1005 are loosened and the photosensitive drum 501 moves in the direction of the dashed arrow in FIG. 1, the photosensitive drum 501 can be easily moved. Can be removed.

As described above, the photosensitive drum 501 and the other photosensitive drums 502 to 504 can be positioned and centered in the axial direction with high precision, and furthermore, there is no backlash in the connection with the rotating shaft 1005. Therefore, they rotate with high accuracy without rotation unevenness. Therefore, the registration of the image between the respective recording means is favorably performed, and a high-quality multicolor image can be stably obtained.

FIG. 2 schematically shows a drive system of each of the photosensitive drums 501 to 504. The other end of each rotary shaft 1005 is rotatably supported by a side plate 1008.

Next, the rotation control of the ultrasonic motor 1001 will be described.

FIG. 4 is a block diagram showing the configuration of the rotation control system of the ultrasonic motor 1001. As shown in FIG. 4, the ultrasonic motor 1001 is driven by the driver 101 to drive the photosensitive drums 501 (502 to 504). Rotate at a predetermined speed.

The encoder scale 3 is attached to the end of the photosensitive drum 501, and the encoder detector 3 detects a signal on the encoder scale 3 which rotates integrally with the photosensitive drum 501. The counter 103 counts the amount of signal moved during the rotation of the controller 103, and the value is counted by the controller 1.
Work on 04.

Then, the controller 104 operates the driver 101 so that the count value of the signal amount becomes equal to the set value.
To control the ultrasonic motor 1001 to control the rotation of the photosensitive drum 501 with high accuracy.

Similarly, by detecting a signal on the encoder scale 3 by the encoder detector 102B,
The absolute position of the photosensitive drum 501 during rotation is determined by a counter 103.
B counts and addresses the value to controller 104B.

In this embodiment, the encoder detectors 102 and 102B capable of detecting the encoder scale 3 from the surface of the photosensitive drum 501 (perpendicular to the photosensitive drum axis).
However, a configuration in which detection is performed from any direction may be adopted as long as the characteristics of the encoder can be sufficiently exhibited and the same behavior as the photosensitive drum 501 is performed. An encoder composed of the encoder scale 3 and the encoder detection unit 102 is an optical encoder,
Any type such as a magnetic type may be used.

In this embodiment, an ultrasonic motor is used as a drive source of the photosensitive drum, but a stepping motor may be used. Other motors may be used as long as they can rotate in both forward and reverse directions.

Further, in this embodiment, a screw is used at the joint between the photosensitive drum and the rotary shaft, but a bayonet or the like that can be satisfactorily coupled by using a rotational force may be used.

<Second Embodiment> Next, a second embodiment of the present invention will be described with reference to FIGS. 5 is a sectional view showing a state before the photosensitive drum is mounted, FIG. 6 is a sectional view showing a state after the photosensitive drum is mounted, FIG. 7 is a sectional view showing a state when the photosensitive drum is removed, and FIG. FIG. 9 is a perspective view of the opposite side plate, and FIG. 9 is a perspective view of the photosensitive drum support shaft on the side opposite to the motor side.

Also in this embodiment, the ultrasonic motor 2
001 is fixed to the side plate 2002, and a part of the rotating shaft 2005 of the ultrasonic motor 2001 has a large diameter portion 2005.
a and a male screw portion 2005b.

On the other hand, flanges 502A and 502B are fitted on both ends of the photosensitive drum 502, and a circular hole 502a and a female screw portion 502b are formed in one (motor side) flange 502A, and the other. As shown in FIG. 8, a circular hole 502c, a two-way hole 502d, and a circular hole 502e having a diameter larger than the maximum outer diameter of the hole 502d are formed in the flange 502B on the (non-motor side) side.

The distal end of the support shaft 2015 is fitted in the circular hole 502c formed in the flange 502B. As shown in FIG. 9, the support shaft 2015 is formed with a chamfered portion 2015a. I have.

The support shaft 2015 is integrally formed with the support shaft fixing member 2020 so as to protrude therefrom.
20 has two support shaft positioning pins 2021 protruding therefrom. The support shaft 2015, the support shaft fixing member 2020, and the support shaft positioning pin 2021 are integrated to form a support shaft unit 2030.

On the other hand, as shown in FIG. 8, holes 2012a, 2012a ', 2012b, 2012 into which the support shaft positioning pins 2012 are to be inserted are formed in the side plate 2012.
b ′ are provided, and the portions where the holes 2012b and 2012b ′ are provided are formed on the photosensitive drum 5 by bending or the like.
It protrudes at a position closer to 02.

Next, the operation of attaching and detaching the photosensitive drum 502 will be described. The description of the same parts as in the first embodiment is omitted.

First, when the photosensitive drum 502 is mounted (when the photosensitive drum 502 is mounted).
In FIG. 5, as shown in FIG. 5, the support shaft unit 2030 is mounted with the two-way portion 2015a of the support shaft 2015 inserted in the two-way hole 502d formed in the flange 502B of the photosensitive drum 504. ,At this time,
The positioning pins 2021 of the support shaft unit 2030 are inserted into the holes 2012a and 2012a 'of the side plate 2012.

The support shaft unit 2030 is connected to the side plate 2.
Immediately before hitting 012, external thread 2 of rotary shaft 2005
005b and the end of the female screw portion 502b on the photosensitive drum 502 side are in contact with each other. Here, as in the first embodiment, when the ultrasonic motor 2001 is driven and the rotating shaft 2005 rotates in the same direction as during recording, the photosensitive drum 502 advances in the direction of the arrow in FIG. At this time, the chamfered portion 2015 of the support shaft 2015
Since a is inserted into the two-way hole 502d formed in the flange 502B of the photosensitive drum 502, the photosensitive drum 502 does not rotate with the support shaft 2015.

Thus, as shown in FIG.
Outer end surface N ₂ 02 of the flange 502A and the rotation shaft 2005
Large the diameter end surface N ₁ part of 2005a are mounted to complete the photosensitive drum 502 in contact, at the same time when the pressing means (not shown) is released, the flange 502B of the beveled portion 2015a and the photosensitive drum 504 of the support shaft 2015 The formed two-way hole 502d is no longer in the inserted state, and the support shaft 20d is not inserted.
Reference numeral 15 indicates that the photosensitive drum 502 is supported only by the inner peripheral portion of the circular hole 502c. Since the inner peripheral portion of the circular hole 502c does not stop the rotation of the photosensitive drum 502, when the mounting of the photosensitive drum 502 is completed, the ultrasonic motor 200
The rotation of the photosensitive drum 502 causes the ultrasonic motor 20 to rotate.
01, and the support shaft 2015 only rotatably supports the photosensitive drum 502.

When removing the photosensitive drum 502 (during removal)
7, first, the support shaft unit 2030 is mounted in the holes 2012b and 2012b '. Since the holes 2012b and 2012b 'are provided at positions near the photosensitive drum 502 in the axial direction of the photosensitive drum 502 as described above, the chamfered portion 2015a of the support shaft 2015 is provided.
The support shaft 2015 and the photosensitive drum 502 are inserted again into the two-way hole 502d on the photosensitive drum 502 side.
Means that no relative rotation is performed. Then, by driving the ultrasonic motor 2001 to rotate the rotating shaft 2005 in a direction different from that during recording, the rotating shaft 2005 and the photosensitive drum 502 rotate relative to each other, and the photosensitive drum 502 is moved in a direction indicated by a broken line in the direction opposite to the direction of mounting. Move in the direction to disconnect.

Thus, according to the present embodiment, the mounting and dismounting of the photosensitive drum 502 can be performed reliably and easily.

Since the operation at the time of recording an electrophotographic image is the same as that of the first embodiment, the description thereof is omitted.

In the present embodiment, the configuration is adopted in which the rotation of the photosensitive drum when the photosensitive drum is attached or detached is realized by a two-way shaft and a hole. However, a structure in which a mechanism such as a clutch is provided on the shaft side is employed. May be.

[0057]

As is apparent from the above description, according to the present invention, in a recording apparatus that performs recording by rotating a photosensitive drum, the photosensitive drum can be detached by the rotational force of a photosensitive drum rotation driving motor. Accordingly, high-quality images can be stably obtained by eliminating rotation unevenness of the photosensitive drum.

[Brief description of the drawings]

FIG. 1 is a partial cross-sectional view illustrating a configuration of a photosensitive drum drive mechanism and a detachable structure of a photosensitive drum of a recording apparatus according to Embodiment 1 of the present invention.

FIG. 2 is a schematic plan view showing an arrangement of a photosensitive drum and an ultrasonic motor of the recording apparatus according to the first embodiment of the present invention.

FIG. 3 is a sectional view of a main part of the multicolor recording apparatus according to the first embodiment of the present invention.

FIG. 4 is a block diagram illustrating a configuration of a rotation control system of an ultrasonic motor in the recording apparatus according to the first embodiment of the present invention.

FIG. 5 is a cross-sectional view illustrating a state before mounting a photosensitive drum in the recording apparatus according to Embodiment 2 of the present invention.

FIG. 6 is a cross-sectional view illustrating a state after mounting a photosensitive drum in the recording apparatus according to Embodiment 2 of the present invention.

FIG. 7 is a cross-sectional view showing a state when a photosensitive drum is removed in a recording apparatus according to Embodiment 2 of the present invention.

FIG. 8 is a perspective view of a side plate on a side opposite to a motor side of the recording apparatus according to the second embodiment of the present invention.

FIG. 9 is a perspective view of a photosensitive drum support shaft on a side opposite to a motor side of the recording apparatus according to Embodiment 2 of the present invention.

[Explanation of symbols]

501 to 504 photosensitive drum 1001, 2001 ultrasonic motor (photosensitive drum rotation drive motor) 1005, 2005 rotating shaft 2015 support shaft 2020 support shaft unit

Claims (12)

[Claims] 1. A recording apparatus for performing recording by rotating a photosensitive drum, wherein the photosensitive drum is detachable by a rotating force of a motor for rotating the photosensitive drum. 2. The recording apparatus according to claim 1, wherein when the photosensitive drum is mounted, the photosensitive drum rotation drive motor rotates in the same direction as when recording an image. 3. The recording apparatus according to claim 1, wherein when the photosensitive drum is detached, the photosensitive drum rotation driving motor rotates in a direction opposite to the direction during image recording. 4. A recording apparatus according to claim 1, further comprising a photosensitive drum rotation preventing means for preventing relative rotation between a rotation shaft of the photosensitive drum rotation drive motor and the photosensitive drum when the photosensitive drum is attached or detached. 5. A recording apparatus according to claim 4, wherein a part of said photosensitive drum rotation preventing means is provided on a support shaft opposite to a rotation shaft of said photosensitive drum rotation drive motor. 6. The photosensitive drum rotation preventing means includes a one-way or two-way portion provided on the support shaft and a one-way or two-way or substantially rectangular hole provided on the photosensitive drum side. 6. The recording apparatus according to claim 5, wherein: 7. A recording apparatus according to claim 5, wherein said photosensitive drum rotation preventing means comprises a clutch provided on said support shaft. 8. The recording apparatus according to claim 4, wherein the same photosensitive drum rotation preventing means is used when removing the photosensitive drum as when mounting the photosensitive drum. 9. The recording apparatus according to claim 1, wherein said photosensitive drum rotation drive motor is an ultrasonic motor. 10. The photosensitive drum rotation driving motor is a stepping motor.
Or the recording device according to 8. 11. The recording apparatus according to claim 1, wherein the same number of photosensitive drums and photosensitive drum rotation motors are provided. 12. The recording apparatus according to claim 1, comprising a plurality of photosensitive drums.