JPH07181773A - Photosensitive drum drive mechanism - Google Patents

Abstract

(57) [Summary] (Correction) [Purpose] To provide a photosensitive drum drive mechanism that enables switching between full-color mode and monochrome mode using a single drive motor. A drive selection member 4 connected to a drive shaft 2 of a photosensitive drum drive motor 1 and idling when a rotation restriction force of a predetermined amount or more is received, and a drive selection member stopped at a first position
A stop member 5, a second stop member 6 that stops the drive selection member in the second position, a transmission rotary body 7 that transmits a driving force, and a drive selection member that is attached to the first shaft 8 and is rotationally driven by the transmission rotary body. Is in the first position, the first rotary member 10 that rotationally drives the monochrome photosensitive drum 16 and the color photosensitive drums 23 and 28 that are mounted on the second shaft 9 and the drive selection member is in the first position. 31 is rotationally driven, and the monochrome photosensitive drum 16 is rotationally driven when it is in the second position.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a photosensitive drum driving mechanism, and more particularly to an electrophotographic apparatus capable of switching between a monochrome mode using a monochrome photosensitive drum and a full color mode using a monochrome photosensitive drum and a color photosensitive drum. The present invention relates to a photosensitive drum driving mechanism in a color printer of the type.

[0002]

2. Description of the Related Art In an electrophotographic color printer, a full color mode and a monochrome mode can be switched and used. Usually, in the monochrome mode, added value is added so that the monochrome mode can be used at a higher speed than in the full color mode. For this reason, conventionally, a total of two drive motors each provided with a drive motor for driving three color photosensitive drums for three primary colors and a motor for driving a monochrome photosensitive drum have been provided.

In the monochrome mode, only the monochrome photosensitive drum is used, whereas in the full color mode, the monochrome photosensitive drum is used together with the three color photosensitive drums for the three primary colors. A photosensitive drum is also used together. Therefore, in the full color mode of the conventional electrophotographic color printer, the drive motor for driving the color photosensitive drum and the drive motor for driving the monochrome photosensitive drum are used at the same time.

[0004]

In the conventional electrophotographic color printer, the color and monochrome photosensitive drums are driven by their own drive motors, respectively. If the rotation accuracy and the rotation characteristics are not matched, color misregistration occurs and it is difficult to obtain a high-definition color image. Further, there is a problem that a special control is required to match the rotation accuracy and the rotation characteristics of the plurality of drive motors, resulting in a significant increase in cost.

SUMMARY OF THE INVENTION Therefore, an object of the present invention is to solve the above problems of the prior art, and to use a single drive motor in an electrophotographic color printer to switch between a full color mode and a monochrome mode for a photosensitive drum drive mechanism. Is to provide.

[0006]

In order to achieve the above object, a photosensitive drum driving mechanism according to the present invention includes a monochrome mode in which a monochrome photosensitive drum is used and a full-color mode in which the monochrome photosensitive drum and a color photosensitive drum are used. In a photosensitive drum drive mechanism in an electrophotographic color printer capable of switching between modes, a drive for idling when a photosensitive drum drive motor and a drive shaft of the photosensitive drum drive motor are connected and a rotation limiting force of a predetermined amount or more is received. A selection member; a first stop member for applying a rotation restriction force of a predetermined amount or more to the drive selection member to stop the drive selection member at a first position; A second stop member for applying a limiting force to stop the drive selection member in the second position, and the photosensitive drum mounted on the drive shaft. The transmission rotating body that transmits the driving force of the drive motor, and the monochrome when the drive selecting member is mounted on the first shaft connected to the drive selecting member and is rotationally driven by the transmitting rotating body and is in the first position. A first rotating body that rotationally drives the photosensitive drum for use, and a color that is mounted on a second shaft connected to the drive selecting member and is rotationally driven by the transmitting rotating body when the drive selecting member is in the first position. A second rotary member that rotationally drives the photosensitive drum for use in black and white and rotates the photosensitive drum for monochrome when in the second position.

A photosensitive drum driving mechanism in an electrophotographic color printer capable of switching between a monochrome mode using a monochrome photosensitive drum and a full color mode using the monochrome photosensitive drum and the color photosensitive drum is used. A drive motor, a drive selection member which is connected to the drive shaft of the photosensitive drum drive motor and idles when a rotation limiting force of a predetermined amount or more is received, and the rotation limiting force of a predetermined amount or more is added to the drive selecting member. A first stop member that stops the drive selection member at a first position; and a second stop member that applies the rotation restriction force of a predetermined amount or more to the drive selection member and stops the drive selection member at a second position. Connected to the drive selection member and a transmission rotating body that is mounted on the drive shaft and transmits the drive force of the photosensitive drum drive motor. A first rotary member mounted on a first shaft and rotationally driven by the transmission rotary member to drive the monochrome photosensitive drum to rotate when the drive selection member is in the first position or the second position; A second shaft which is mounted on a second shaft connected to the member and is rotationally driven by the transmission rotary member to rotationally drive the color photosensitive drum when the drive selection member is in the first position;
And a rotating body.

[0008]

When the first or second stop member applies a rotation limiting force of a predetermined amount or more to the drive selection member, the drive selection member stops at the first position or the second position via the torque limiter bearing. When the drive selection member is in the first position, the first rotating body rotationally drives the monochrome photosensitive drum, the second rotating body rotates the color photosensitive drum, and when the drive selecting member is in the second position. Since the two rotating bodies drive the monochrome photosensitive drum to rotate, the monochrome photosensitive drum and the color photosensitive drum can be independently driven by the single photosensitive drum drive motor.

Further, the drive selection member is at the first position or the second position.
The first rotating body rotationally drives the monochrome photosensitive drum when the drive selecting member is in the second position when the drive selecting member is in the second position.
Since the rotating body rotationally drives the monochrome photosensitive drum, the monochrome photosensitive drum and the color photosensitive drum can be independently driven by the single photosensitive drum drive motor.

[0010]

Embodiments of the present invention will be described below with reference to the drawings. A first embodiment of the present invention will be described with reference to FIGS. In FIG. 1, reference numeral 1 denotes a photosensitive drum drive motor, and a torque limiter bearing 3 is rotatably mounted on a drive shaft 2 of the photosensitive drum drive motor 1. The torque limiter bearing 3 normally rotates in a state of being fixed to the drive shaft 2, and idles around the drive shaft 2 when the force that impedes the rotation exceeds a predetermined magnitude. A triangular plate-shaped drive selection member 4 is fixed around the torque limiter bearing 3. The drive selection member 4 normally rotates around the drive shaft 2 and runs idle through the torque limiter bearing 3 when receiving a rotation limiting force of a predetermined magnitude or more.

Within the range in which the drive selection member 4 rotates about the drive shaft 2, a first stop member 5 for applying a rotation limiting force to the drive selection member 4 to stop the drive selection member 4 at the first position, and the drive selection member 4 are provided.
And a second stop member 6 for applying a rotation limiting force to stop at a second position. The 1st stop member 5 and the 2nd stop member 6 have stop parts 6a and 6b which can be projected. When the stopper 6a or the stopper 6b is projected by a control device (not shown), the stopper 6a contacts the peripheral edge of the drive selection member 4 and a rotation limiting force is applied to the drive selection member 4, so that the drive selection member 4 is in the first position or the second position. Stop at position. Similarly,
The stopping portion 6a or the stopping portion 6 is controlled by a control device (not shown).
Drive selection member 4 which has been stopped when b is retracted
Rotates with the drive shaft 2 until the stop 6a or the stop 6b is next projected.

Here, the first position means a position where the periphery of the drive selection member 4 rotates clockwise as shown in FIG. 2 and is stopped by the first stop member 5. The second position means a position where the periphery of the drive selection member 4 rotates clockwise as shown in FIG. 3 and is stopped by the second stop member 6. At the tip of the drive shaft 2, a transmission rotating body 7 formed of a gear for transmitting the driving force of the photosensitive drum drive motor 1 to the photosensitive drum is fixed.

A first shaft 8 and a second shaft 9 are erected on the drive selection member 4. A first rotating body 10 formed of a gear is rotatably fixed to the first shaft 8, and a second rotating body 11 formed of a gear is rotatably fixed to the second shaft 9. The teeth of the gears of the first rotating body 10 and the second rotating body 11 correspond to the transmission rotating body 7
Is in a position where it always meshes with the teeth of the gear of
The second rotating body 11 is rotating in response to the rotation of the transmitting rotating body 7.

A monochrome photosensitive drum drive gear 12 is fixed to a shaft 13 at a position where the teeth of the first rotating body 10 can mesh with each other. A belt gear 14 is fixed to the other end of the shaft 13 and is drivingly connected to a belt gear 18 fixed to a driving shaft 17 of a monochrome photosensitive drum 16 by a driving belt 15.

A color photosensitive drum drive gear 19 is fixed to the shaft 20 at a position where the teeth of the second rotating body 11 can mesh with each other. A belt gear 21 is fixed to the other end of the shaft 20. One end of the cylindrical connecting body 22 is connected to the tip end of the belt gear 22 on an extension of the axis of the shaft 20, and the other end of the cylindrical connecting body 22 is fixed to the drive shaft 24 of the color drum 23. The drum 23 is rotated via the cylindrical connecting body 22. Further, drive belts 26 and 27 are mounted adjacent to each other at the end of the gear 21. Drive belt 2
The other end of 6 is mounted on a belt gear 30 fixed to the tip of a drive shaft 29 of the color photosensitive drum 28, and the color photosensitive drum 28 is rotationally driven via a drive belt 26.
The other end of the drive belt 27 has the color photosensitive drum 31.
The color photosensitive drum 31 is mounted on a belt gear 33 fixed to the front end of the drive shaft 32, and is rotationally driven via the drive belt 27.

Next, the operation of this embodiment will be described with reference to FIGS. In order to select the full color mode, it is necessary to drive both the monochrome photosensitive drum 16 and the color photosensitive drums 23, 28, 231. For this purpose, the first stop member 5 is controlled by a control device (not shown).
Of the second stop member 6 is retracted, and the peripheral edge of the drive selecting member 4 rotating clockwise is brought into contact with the stop portion 5a. When the drive selection member 4 further tries to rotate, a rotation restriction force of a predetermined amount or more is applied to the peripheral edge. At this time, the torque limiter bearing 3 starts idling,
Only the drive shaft 2 rotates, and the drive selection member 4 fixed to the torque limiter bearing 3 stops at the first position as shown in FIG.

In this first position, the first rotating body 10
And the second rotator 11 are drivingly connected to the monochrome photosensitive drum drive gear 12 and the color photosensitive drum drive gear 19, respectively, so that the monochrome photosensitive drum 16 and the color photosensitive drums 23, 28 and 31 are driven together. To be done.

In order to select the monochrome mode, it is necessary to drive only the monochrome photosensitive drum 16. For this purpose, a stopper (6a) of the second stopper (6) is pushed out by a controller (not shown) and the stopper (5a) of the first stopper (5) is retracted, and the peripheral edge of the clockwise drive selecting member (4) is brought into contact with the stopper (6a). Let When the drive selection member 4 further tries to rotate, a rotation restriction force of a predetermined amount or more is applied to the peripheral edge,
The torque limiter bearing 3 starts idling, and the drive selection member 4 fixed to the torque limiter bearing 3 stops at the second position as shown in FIG.

In this second position, the second rotating body 11
Is drivingly connected to the monochrome photosensitive drum drive gear 12,
Only the monochrome photosensitive drum 16 is driven.

As described above, according to the structure of the present embodiment, when the rotation restriction force of a predetermined amount or more is applied to the drive selection member 4 by the first stop member 5 or the second stop member 6, the drive selection member 4 is driven. 4 stops at the first position or the second position via the torque limiter bearing 3, and when the drive selection member 4 is at the first position, the first rotating body 10 causes the monochrome photosensitive drum 16 to move.
And the second rotating body 11 rotates the photosensitive drum 2 for color.
3, 28, 31 are rotationally driven, and when the drive selection member 4 is at the second position, the second rotary body 11 rotationally drives only the monochrome photosensitive drum 16, so that the single photosensitive drum drive motor 1 The monochrome photosensitive drum 16 and the color photosensitive drums 23, 28, 31 can be independently driven.

As a result, in comparison with the case where the photosensitive drums for color and monochrome are driven by using the dedicated drive motors respectively, a high-definition color image is obtained without causing color misregistration in the full color mode. be able to. Further, when a plurality of drive motors are used, the cost required for matching the rotation accuracy and the rotation characteristics can be omitted, and the number of drive motors to be used can be reduced to a single cost.

Next, a second embodiment of the present invention will be described with reference to FIGS. 4 and 5, the first rotary body 10, the second rotary body 11, the monochrome photosensitive drum drive gear 12, the color photosensitive drum drive gear 19, etc. are the same as those of the first embodiment shown in FIGS. 1 to 3. The case where the left and right are arranged opposite to the example is shown.

In this embodiment, a diamond plate-shaped drive selecting member 104 is provided instead of the drive selecting member 4. The drive selection member 104 is rotatable in a clockwise normal direction indicated by an arrow h and a counterclockwise reverse direction indicated by an arrow i.

A third shaft (not shown) is erected on the drive selection member 104, and the third shaft 100 is provided at a position where the teeth of the second shaft 11 mesh with the third shaft. The third rotating body 100 is connected and driven via the second rotating body 11 according to the rotation of the drive shaft 2.

Further, in this embodiment, the first stopping member 105 and the second stopping member 106 are fixed type stoppers, and are always in a position where they can contact the drive selecting member 104.

FIG. 4 shows the arrangement in the full color mode, and FIG. 5 shows the arrangement in the monochrome mode. The first rotating body 10 is
In the full color mode, as in the case of the first embodiment, the driving gear 12 is directly connected to the monochrome photosensitive drum drive gear 12.
On the other hand, in the monochrome mode, the first rotating body 10
Unlike the case of the first embodiment, it is drivingly connected to the monochrome photosensitive drum drive gear 12 via the third rotating body 100.

According to the configuration of this embodiment, the drive selection member 1
Since 04 can perform forward / reverse rotation motion, it is possible to quickly switch between the full-color mode and the monochrome mode.

Further, since the first stopping member 105 and the second stopping member 106 are of a fixed type, it is not necessary to control the withdrawal / removal of the stopper, so that the full color mode and the monochrome mode can be easily switched.

Needless to say, the present invention is not limited to these embodiments and can be modified in various ways.

For example, instead of the torque limiter bearing,
It is also possible to use a slide bearing which causes idling by receiving a predetermined rotation limiting force.

Any tooth profile may be used for each gear.

[0032]

As described above, according to the configuration of the present invention, the monochrome photosensitive drum and the color photosensitive drum are driven by the single photosensitive drum drive motor, and the full color mode and the monochrome mode are simplified. Can be switched to.

As a result, in comparison with the case where the photosensitive drums for color and monochrome are driven by using dedicated drive motors respectively, a high-definition color image can be obtained without causing color misregistration in the full color mode. be able to. Further, when a plurality of drive motors are used, the cost required for matching the rotation accuracy and the rotation characteristics can be omitted, and the number of drive motors to be used can be reduced to a single cost.

[Brief description of drawings]

FIG. 1 is a perspective view showing a first embodiment of a photosensitive drum driving mechanism of the present invention.

FIG. 2 is a sectional view showing the arrangement of a full color mode in the first embodiment of the present invention.

FIG. 3 is a sectional view showing the arrangement of the monochrome mode.

FIG. 4 is a sectional view showing the arrangement of a full color mode in a second embodiment of the photosensitive drum driving mechanism of the present invention.

FIG. 5 is a sectional view showing the arrangement of the monochrome mode.

[Explanation of symbols]

 1 Photosensitive Drum Drive Motor 2 Drive Shaft 3 Torque Limiter Bearing 4 Drive Selection Member 5 First Stopping Member 6 Second Stopping Member 7 Transmission Rotating Body 8 1st Shaft 9 2nd Shaft 10 1st Rotating Body 11 2nd Rotating Body 12 Monochrome Photosensitive drum drive gear 16 monochrome photosensitive drum 19 color photosensitive drum drive gear 23 color photosensitive drum 28 color photosensitive drum 31 color photosensitive drum

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Manabu Mikami 1 Komukai Toshiba-cho, Kouki-ku, Kawasaki-shi, Kanagawa Toshiba Research & Development Center

Claims (2)

[Claims] 1. A photosensitive drum driving mechanism in an electrophotographic color printer capable of switching between a monochrome mode using a monochrome photosensitive drum and a full color mode using the monochrome photosensitive drum and a color photosensitive drum. A drive motor, a drive selection member which is connected to the drive shaft of the photosensitive drum drive motor and idles when a rotation limiting force of a predetermined amount or more is received, and the rotation limiting force of a predetermined amount or more is added to the drive selecting member. A first stop member that stops the drive selection member at a first position; and a second stop member that applies the rotation restriction force of a predetermined amount or more to the drive selection member and stops the drive selection member at a second position. A transmission rotary member mounted on the drive shaft for transmitting the driving force of the photosensitive drum drive motor, and a first connected to the drive selection member. And a second shaft connected to the drive selecting member, the first rotating member being mounted on the first rotating body and rotationally driven by the transmission rotating body to rotationally drive the monochrome photosensitive drum when the drive selecting member is in the first position. Mounted on the drive roller and rotationally driven by the transmission rotator to rotationally drive the color photosensitive drum when the drive selection member is in the first position and rotationally drive the monochrome photosensitive drum when in the second position. A second rotating body; and a photosensitive drum drive mechanism. 2. A photosensitive drum driving mechanism in an electrophotographic color printer capable of switching between a monochrome mode using a monochrome photosensitive drum and a full color mode using the monochrome photosensitive drum and a color photosensitive drum. A drive motor, a drive selection member which is connected to the drive shaft of the photosensitive drum drive motor and idles when a rotation limiting force of a predetermined amount or more is received, and the rotation limiting force of a predetermined amount or more is added to the drive selecting member. A first stop member that stops the drive selection member at a first position; and a second stop member that applies the rotation restriction force of a predetermined amount or more to the drive selection member and stops the drive selection member at a second position. A transmission rotary member mounted on the drive shaft for transmitting the driving force of the photosensitive drum drive motor, and a first connected to the drive selection member. Connected to the drive selecting member and a first rotating body that is rotatably driven by the transmission rotating body and rotationally drives the monochrome photosensitive drum when the drive selecting member is in the first position or the second position. A second rotating body that is mounted on a second shaft that is rotationally driven by the transmission rotary body and that rotationally drives the color photosensitive drum when the drive selection member is at the first position. A photosensitive drum drive mechanism characterized by the above.