JPH0830061A - Motor driving device - Google Patents

Abstract

PURPOSE:To prevent the sticking of foreign objects fallen at the time of attaching an attachable/detachable unit to a supporting shaft and incursion thereof between gears and to prevent generation of noises, vibrations and sudden wear in a motor driving device for attaching the attachable/detachable unit into a device main body freely attachably/detachably. CONSTITUTION:In a device man body side to which a developing unit 25 (attachable/detachable unit is fitted, the supporting shaft 48 of a gear 55 is covered by a color member 50, a coil spring 51 is wound on the supporting shaft 48 via the color member 50 and near its tip, the gear 55 is integrally provided so as to be freely slidable on the color member 50 and rotatable. The gear 55 is pressed to the tip direction of the supporting shaft 48 by means of the coil spring 51 and enagaged with a gear 60 provided in another developing unit 25 in an engaging position. Thus, when the developing unit 25 is attached into the device main body, the gear 55 is slid on the color member 50, a the supporting shaft 48 is kept covered by the color member 50.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention
The present invention relates to a motor drive device, such as a copying machine or a facsimile, which has a detachable unit such as a developing unit and a cleaning unit that is detachably attached to the inside of an apparatus body and transmits the rotation of a drive motor to the detachable unit to drive the detachable unit.

[0002]

2. Description of the Related Art Conventionally, among motor drive devices of this type, for example, laser printers, there is a device in which, for example, a developing unit is detachably mounted in the main body of the device and is replaceable. Then, as shown in FIG. 12, for example, as shown in FIG.
And the drive motor 2 is attached to the frame 1.
Further, on the frame 1, the support shafts 3 and 4 are erected in parallel above the drive motor 2 in the figure, and the gears 5 and 6 are rotatably supported by the support shafts 3 and 4, respectively. A coil spring 7 is wound around 3 to urge the gear 5 toward the tip end of the support shaft 3, and the gear portion 6 meshed with the motor gear 2a is meshed with the tooth portion 5a of the gear 5 at the bias position. On the other hand,
On the developing unit side on the left side of the drawing, a gear 9 is fixed to a support shaft 8a of a developing sleeve 8 provided in the developing unit, and the gear 9 is meshed with a tooth portion 5b of the gear 5.

By the way, when the developing unit is mounted in the main body of the apparatus, the gear 9 is butted against the gear 5 when the developing unit is inserted in the direction of arrow A in the figure, and the gear 5 is inserted as shown in FIG. The coil spring 7 is bent by sliding. Then, after the developing unit is assembled, when the drive motor 2 is operated, the gear 5 is rotated to release the abutment, and the gear 5 is slid back by the urging force of the coil spring 7, as shown in FIG. It again meshed with the gear 9 and transmitted the rotation to the gear 9.

[0004]

By the way, when the developing unit is mounted, foreign matter such as scattered developer or dust attached to the gear 9 of the developing unit 1 falls due to the vibration of the mounting. However, conventionally, when the developing unit is attached, as shown in FIG. 13, when the gear 5 is slid along with the insertion of the developing unit, the support shaft 3 is exposed at the tip end side thereof, so that the foreign matter that has fallen on the tip end side is retained. It adheres and further enters between the support shaft 3 and the gear 5, which causes noise and vibration, and the contact surface between the support shaft 3 and the gear 5 is rapidly worn away. It was

Therefore, an object of the present invention is to prevent foreign matter from adhering to the support shaft and entering the space between gears when the detachable unit is attached in the motor drive device as described above,
The purpose is to prevent abnormalities such as noise, vibration, and sudden wear.

[0006]

Therefore, the present invention provides
For example, as in the following embodiment shown in FIGS.
A detachable unit such as the developing unit 25 is detachably attached to the inside of the apparatus main body 11, and a frame 45 and a support shaft 48 standing on the frame 45 are attached to the apparatus main body 11 side.
A first gear, such as a gear 55, which transmits the rotation of the drive motor 47 and rotatably supports the drive motor 47 about the support shaft 48, and the first gear wound around the support shaft 48 to support the first gear. A coil spring 51 for urging the shaft 48 toward the tip end direction is provided, and when the detachable unit is attached to the inside of the apparatus main body 11, the detachable unit is inserted and the first gear is protruded. In the motor drive device, a second gear, such as a gear 60, which is applied and further inserted and whose first gear is slid in the axial direction of the support shaft 48 to bend the coil spring 51, is provided in the motor drive device. A collar member 50 is provided on the outer periphery of the first gear, and the first gear is slidable on the collar member 50 through the collar member 50, but is rotatable integrally therewith. Provided with, made by winding the coil spring 51 to the support shaft 48, characterized in that.

According to a second aspect of the present invention, as in the following embodiment shown in FIG. 6, for example, in the motor drive unit according to the first aspect, the coil spring 51 is connected to the first coil spring 51.
It is provided between the gear and the collar member 50. According to the third aspect, for example, FIG.
In the motor drive device according to the second aspect of the present invention, the collar member 50 urged by the coil spring 51 is received by the support shaft 48.

According to a fourth aspect of the present invention, in the motor drive device according to the first aspect, for example, as in the following embodiments shown in FIGS.
8a to cover the support shaft 48, and the base 4 of the support shaft 48.
The collar member 50, which is engaged with 8c to prevent the collar from coming off, is attached to the support shaft 48. According to a fifth aspect of the invention, as in the following embodiments shown in FIGS. 8 to 11, in the motor drive device of the fourth aspect, the first gear that is biased by the coil spring 51 is It is characterized in that it is received by the collar member 50.

[0009]

According to the present invention, when the detachable unit is mounted in the apparatus main body 11, the second gear is brought into contact with the first gear together with the insertion of the detachable unit, and the collar member 50 is also attached with the second gear. The first gear is slid to bend the coil spring 51. When the drive motor 47 is operated after the attachment / detachment unit is assembled, the first gear is rotated together with the collar member 50 to release the abutment, and the coil spring 51 urges the first gear on the collar member 50. Slide the gear back and back again
And meshes with the gear of the second gear to transmit the rotation to the second gear.

According to the second aspect of the present invention, when the first gear rotates, the collar member 50 rotates integrally with it, and the coil spring 51 also rotates. According to the third aspect, the collar member 50 is rotated while being separated from the frame 45 and in contact with the support shaft 48.

According to the fourth aspect of the present invention, the collar member 50 is covered by covering the tip portion 48a of the support shaft 48, and the collar member 50 is engaged with the base portion 48c of the support shaft 48 to prevent the support shaft 48 from coming off. The coil spring 51 according to claim 5
The collar member 50 receives the first gear urged by.

[0012]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 4 shows a schematic structure of a color laser copying machine which is an embodiment of the present invention.

This color laser copying machine is designated by reference numeral 10 in the drawing.
The apparatus main body 11 is placed on the paper storage stand indicated by, and the color scanner 12 is placed thereon. The paper storage stand 10 is equipped with paper feed cassettes 13 and 14 therein. The color scanner 12 is provided with a contact glass 15 for setting a copy document G on the upper surface thereof, and has a light source 16 and a mirror 1 inside.
7a, 17b, 17c, an image forming lens 18, and a color sensor 19, and read a color image of the original G for each color separation light of black, blue, yellow, and red to convert it into an electric image signal. To do.

Inside the apparatus main body 11, a drum-shaped photosensitive member 20 is provided substantially at the center thereof. Around the photoconductor 20, a charger 21, a developing unit 25,
An intermediate transfer belt unit 24, a photoconductor cleaning unit 23, and a static eliminator 22 are provided. Further, an optical writing unit 26 is provided on the photoconductor cleaning unit 23,
A belt cleaning unit 27 is provided on the developing unit 25 side of the intermediate transfer belt unit 24. Further, a carrier 28 is provided below the developing unit 25, and the carrier 2
8 is provided with a paper transfer unit 29 on the right side in FIG.
Is provided.

The intermediate transfer belt unit 24 stretches the transfer belt 30 between a plurality of rollers such as a drive roller 35, a bias roller 36, and a driven roller 37, which are sequentially provided in the direction of the arrow. The transfer belt 30 can be driven in the direction of the arrow at the same speed as the photoconductor 20 by appropriately controlling the driving force transmitted from a driving motor (not shown). In addition, the developing unit 25
Are black from the top in the driving direction of the photoconductor 20 (Blac
k) ・ Yellow ・ Red (Magenta)
・ Blue (Cyan) developing devices 25a ・ 25b ・ 25c ・
25d.

Further, the apparatus main body 11 is provided with a paper feed cassette 33 on the bottom thereof and a paper feed cassette 34 on the right side in the drawing. Then, sheets of various sizes are stored in the sheet feeding cassettes 33 and 34 and the sheet feeding cassettes 13 and 14 described above. A manual paper feed tray 38 is provided above the paper feed cassette 34.

Now, when making a copy of the copy original G,
The original G is placed on the contact glass 15 and set, the paper size is appropriately selected, and copying is started.
Then, for example, the paper P is fed from the paper feed cassette 34 with an arrow A.
And the sheet P is conveyed to the lower side of the transfer belt 30 by the registration roller 39 at a timing.
The color scanner 12 reads, for example, a black image (first color image) on the copy document G and converts it into an image signal.

On the other hand, the photoconductor 20 is driven in the counterclockwise direction indicated by the arrow, and at that time, the surface thereof is uniformly charged by the charger 21.
An optical writing unit 2 is provided on the surface of the black image signal based on the black image signal.
At 6, a laser beam is irradiated to form an electrostatic latent image. Then
When passing through the position of the black developing device 25a, the electrostatic latent image is visualized by the black developer. Then, a predetermined bias voltage is applied to the bias roller 36 to transfer the black developer image onto the transfer belt 30. After the transfer, the surface of the photoconductor 20 is cleaned by the photoconductor cleaning unit 23.

Then, the color scanner 12 reads, for example, a blue image (second color image) on the copy original G and converts it into an image signal. Based on the blue image signal, the optical writing unit 26 similarly performs optical writing on the surface of the photoconductor 20 to form an electrostatic latent image on the photoconductor 20, and then passes through the position of the blue developing device 25d. At that time, the electrostatic latent image is developed with a blue developer. Then, while transferring the blue developer image to the transfer belt 30, the surface of the photoconductor 20 is cleaned again by the photoconductor cleaning unit 23. Then, by repeating this, the image of four colors is transferred to form a color image on the transfer belt 30.

Then, a predetermined bias voltage is applied to the transfer bias roller 29a of the paper transfer unit 29, the transfer bias roller 29a is brought into contact with the transfer belt 30, and the color image is applied to the paper P conveyed by the registration roller 39. Transfer at once. After the color transfer, the paper P is conveyed to the fixing device 32 by the conveying device 28, and the color image is fixed by the fixing device 32. After fixing, the paper P is discharged onto the paper discharge tray 41 by the paper discharge roller 40.

On the other hand, after color transfer, the transfer belt 30 is
The surface is cleaned by the belt cleaning unit 27 at the cleaning position indicated by reference character C in FIG.

By the way, the developing unit 25 described above is
It is detachably attached in the axial direction of the photoconductor 20 in the main body 11 of the apparatus, and is provided so that it can be taken in and out from the front side in FIG. And, in each of the developing devices 25a, 25b, 25c, 25d,
The developing paddle 42 and the developing sleeve 43 are rotated by a drive motor and a train wheel which are individually provided.

On the other hand, on the side of the apparatus main body 11 to which the developing unit 25 is attached, as shown in FIG. 1, a plate-like frame 45 is vertically provided. The drive motor and the train wheel are connected to the developing devices 25a, 25b, 25c, 25, respectively.
It is installed corresponding to the mounting position of d, and each is supported by the frame 45 (one of which is shown in FIG. 1).

Then, the drive motor 47 is attached to the frame 45.
Attach. Further, on the frame 45, the support shafts 48 and 49 are located above the drive motor 47 and toward the left side in the drawing.
Stand up and install parallel to each other. A collar member 50 is placed on the outer periphery of the upper support shaft 48 of them. A coil spring 51 is wound around the support shaft 48 via the collar member 50, and a gear 55 is provided near the tip thereof. The collar member 50 is made of, for example, a resin material in the shape of an elongated cylinder, and as shown in FIG. Also,
For example, as shown in FIG. 3, a convex portion b may be provided on the outer circumference over the entire length.

As shown in FIG. 1, the gear 55 is provided with tooth portions 55a and 55b having different diameters in the axial direction of the support shaft 48, and the central shaft hole 5 having a shape corresponding to the D shape of the collar member 50.
5c. Also, when the convex portion b is provided on the outer circumference, the central shaft hole 55c has a shape corresponding to the shape. Although the gear 55 is slidable on the collar member 50, it can be rotated integrally with the collar member 50. Then, the tip portion 48 of the support shaft 48
A stopper plate 52 is attached to the circumferential groove 48b provided on the outer periphery of a. Then, the coil spring 51 urges the gear 55 toward the tip of the support shaft 48. On the other hand, the gear 55
Is held together with the collar member 50 by a stopper plate 52 at the illustrated meshing position.

A gear 56 is rotatably provided on the support shaft 49. The circumferential groove 4 on the outer circumference of the tip of the support shaft 49
A stopper 57 is attached to 9a to prevent the gear 56 from coming off. Then, the gear 56 is engaged with the motor gear 53 and the tooth portion 55a of the gear 55 at the meshing position, and the tooth portion 55b is engaged with the gear 60.

The gear 60 is provided on the other developing unit 25 side, for example, the developing sleeve 43 provided in the developing device 25a.
It is fixed to one end of the support shaft 43a. The developing sleeve 43 has bearing members 5 on both ends of the support shaft 43a.
It is rotatably supported by the opposing side plate 59 via the plate 8.

Now, in the above embodiment, the apparatus main body 1
When mounting the developing unit 25 in the No. 1 unit, the developing unit 25 should be inserted in the direction of the arrow A in the drawing and the gear 60
5 against the gear 55, and with the insertion,
As shown in, the gear 55 is slid on the collar member 50 to bend the coil spring 51.

When the drive motor 47 is operated after the developing unit 25 is assembled, the gear 55 is moved to the collar member 5.
0 and the abutment is released, the gear 55 is slid back on the collar member 50 by the urging force of the coil spring 51, and the gear 55 meshes with the gear 60 again.
Transmits the rotation to.

By the way, in the illustrated embodiment described above,
The front end of the coil spring 51 contacts the gear 55, and the rear end of the coil spring 51 is received by the frame 45. However, according to the present invention, as in the embodiment shown in FIG. 6, for example, a collar-shaped receiving portion 50c is provided at the right base end of the collar member 50 in the figure, and the receiving portion 50c is provided at the rear end side of the coil spring 51. You should try to accept it. Then, the coil spring 51 is provided between the collar member 50 and the gear 55.

When the gear 55 rotates, the gear 5 is rotated.
While rotating the collar member 50 integrally with 5, the coil spring 51 also rotates together between the collar member 50 and the gear 55. And the coil spring 5
Do not scratch the frame 45 at the rear end of 1 or hook the rear end on the frame 45.

Further, according to the present invention, as shown in FIG. 7, for example, a circumferential groove 48d is provided on the outer circumference of the base portion 48c of the support shaft 48, a stopper 65 is attached to the circumferential groove 48d, and a coil spring 51 is used. The biased collar member 50 may be received by the catch 65 of the support shaft 48.

Then, when the collar member 50 is rotated, the collar member 50 is separated from the frame 45 and the stopper 65 is provided.
Rotate while touching.

Further, although not shown, a stopper is not used, but a step portion is provided on the outer periphery of the base portion 48c of the support shaft 48, and the step portion of the support shaft 48 receives the collar member 50. When the member 50 rotates, the collar member 50 may be separated from the frame 45 and rotated while contacting the step.

By the way, according to the present invention, the collar member 50 may be constructed as shown in the following illustrated embodiments, for example.

That is, as shown in FIG. 8, the collar member 50 has a shape in which the left end portion 50e in the drawing has a closed opening, and the front end portion 50e is expanded in diameter to form a rearward facing step portion 50f. On the other hand, as shown in FIG. 9, a plurality of legs are extended rearward at the base end on the right side of the figure, and a claw portion 50g is formed inward at the tip of the leg.

When the collar member 50 is attached to the support shaft 48, the collar member 50 is engaged with the central shaft hole 55c of the gear 55. Then, after winding the coil spring 51 around the collar member 50,
The support shaft 48 is inserted therein, and as shown in FIG. 10, with the claw portions 50g of the collar member 50 elastically deformed, the support shaft 48 is slid over the support shaft 48. Then, as shown in FIG. 8, the tip end portion 48a of the support shaft 48 is covered with the tip end portion 50e of the collar member 50, and as shown in FIG.
Is engaged with the circumferential groove 48d of the support shaft 48 to prevent it from coming off. Then, the gear 55, which is biased by the coil spring 51 toward the tip of the support shaft 48, is attached to the circumferential projection 50 of the collar member 50.
Take it with f to prevent it from coming off.

[0038]

Therefore, according to the present invention, when the detachable unit is mounted in the main body of the apparatus, the first gear is slid on the collar member and the support shaft is covered with the collar member. Foreign matter that has fallen during attachment of the spindle is prevented from adhering to the spindle, and foreign matter is prevented from entering between the collar member that rotates integrally with the first gear and the spindle. It is possible to prevent the occurrence of abnormalities such as wear.

According to the second aspect, the coil spring is provided between the first gear and the collar member, and the first spring is provided.
When the gear is rotated, the collar member is rotated together with it, and the coil spring is also rotated.Therefore, the coil spring rubs the frame to generate a rubbing sound, or the trouble of being caught on the frame occurs. Can be prevented.

According to the third aspect of the present invention, the collar member urged by the coil spring is received by the support shaft, and the collar member is separated from the frame and rotated while being in contact with the support shaft, so that the friction is small. As a result, the rotational load of the first gear can be reduced.

According to the fourth aspect of the present invention, since the collar member is covered by covering the tip of the support shaft, foreign matter dropped when the detachable unit is attached is caught between the stopper and the tip of the support shaft. It also blocks intrusions, which results in noise, vibration,
It is possible to reliably prevent the occurrence of abnormalities such as sudden wear. Further, since the collar member is engaged with the base of the support shaft to prevent the collar member from coming off, it is possible to prevent the collar member from coming off without using a stopper plate or the like.

According to the fifth aspect of the invention, since the first gear that is biased by the coil spring is received by the collar member, the first gear can be easily provided without using a stopper or the like. It is possible to prevent the slipping out.

[Brief description of drawings]

FIG. 1 is a vertical sectional view showing a driving unit of a color laser copying machine according to an embodiment of the present invention in a state where a developing unit is attached.

FIG. 2 is a schematic configuration diagram showing a collar member in the drive unit and a gear attached to the support shaft via the collar member as viewed from the tip end side of the support shaft.

FIG. 3 is a similar schematic configuration diagram of another example.

FIG. 4 is an overall schematic configuration diagram of the color laser copying machine.

5 is a vertical cross-sectional view showing the drive unit shown in FIG. 1 in a state where a gear on the developing unit side is slid to bend a coil spring when the developing unit is attached.

FIG. 6 is a longitudinal sectional view of a portion in which a gear is supported by a support shaft covered with the collar member, which shows another embodiment of the present invention using a collar member having a receiving portion for receiving a coil spring.

FIG. 7 shows still another embodiment of the present invention in which a collar supports a collar member biased by a coil spring.
It is a partial longitudinal cross-sectional view in the receiving part.

FIG. 8 is a vertical cross-sectional view of another portion of the present invention in which the collar member is covered by covering the tip end portion of the support shaft, and in which the gear is supported by the support shaft covering the collar member.

FIG. 9 is a vertical cross-sectional view showing a state in which the claw portion of the collar member is engaged with the circumferential groove of the support shaft.

FIG. 10 is a partial vertical cross-sectional view showing a state in which the claw portion is elastically deformed when the collar member is mounted on the support shaft so as to be attached thereto.

FIG. 11 is a vertical cross-sectional view showing a state in which the claw portion is engaged with the circumferential groove of the support shaft.

FIG. 12 is a vertical cross-sectional view showing a drive unit of a conventional laser copying machine in a state where a developing unit is attached.

FIG. 13 is a vertical cross-sectional view showing the driving unit in a state where a gear on the developing unit side is slid to bend a coil spring when the developing unit is attached.

[Explanation of symbols]

 11 Device Main Body 25 Developing Unit (Detachable Unit) 45 Frame 47 Drive Motor 48 Spindle 48a Spindle Tip 48c Spindle Base 50 Collar Member 51 Coil Spring 55 Gear (First Gear) 60 Gear (Second Gear) )

Claims (5)

[Claims] 1. A detachable unit is detachably mounted in a main body of an apparatus, and a frame, a support shaft erected on the frame, and rotation of a drive motor are transmitted to the main assembly side of the device so that the support shaft mounts the same. A first gear that is rotatably supported as a center and a coil spring that is wound around the support shaft and biases the first gear toward the tip of the support shaft are provided, while the detachable unit side is provided. When mounting it in the apparatus body, the detachable unit is inserted and the first
A motor driving device provided with a second gear for abutting against and further inserting the first gear and sliding the first gear in the axial direction of the support shaft to bend the coil spring. A member is provided, and the first gear is slidable on the collar member via the collar member, but is provided so as to be rotatable integrally therewith, and the coil spring is wound around the spindle. Motor drive device. 2. The motor drive device according to claim 1, wherein the coil spring is provided between the first gear and the collar member. 3. The motor driving device according to claim 2, wherein the collar member urged by the coil spring is received by the support shaft. 4. The collar member according to claim 1, further comprising: a collar member that covers the tip end portion of the support shaft and covers the support shaft, and that engages with a base portion of the support shaft to prevent the collar from coming off. The described motor drive device. 5. The motor drive device according to claim 4, wherein the collar member receives the first gear urged by the coil spring.