JP2001100476A - Drive connection device and image forming device using it - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a drive connection device provided with accurate rotary transmission characteristics and a good operability at attaching/detaching. SOLUTION: A connecting member 35 is arranged on a driving member 31 so that it may be moved in an axial direction, and the movement of the connection member 35 in the axial direction is controlled by an axial direction control member 38, and also, the movement of the member 35 in the rotating direction is controlled by a rotating direction control member 39. Besides, an energizing means 41 for energizing the member 35 so that the member 35 may come into contact with the member 38 is arranged. Besides, a driven member control means 48 for controlling the movement of a driven member 11 toward the driving member 31, positioning means 43 and 47 for making the axial center of the member 11 align with the axial center of the member 31 are arranged. And, pressuring means 42 and 46 for bringing the connecting member 35 into contact with the member 38 in accordance with the rotary movement of the driving member 31, and also bringing the driven member 11 into contact with at least one of the driving member 31 on the member 38 are arranged.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] 1. Field of the Invention [0002] The present invention relates to a drive connecting device and an image forming apparatus using the same.

[0002]

2. Description of the Related Art Conventionally, for example, a photoconductor in an image forming apparatus is detachably connected to a drive shaft for driving the photoconductor. At the time of maintenance work such as cleaning or replacement, or during jam clearance, the connection between the photoconductor and the drive shaft is released so that the photoconductor can be pulled out to the front side of the device, and when the necessary work is completed and the photoconductor is pushed back The photosensitive member is connected to the drive shaft.

There are the following three systems for connecting such a photosensitive member so as to be rotatable with respect to a drive shaft.
In the first method, as shown in FIG. 7, a rotating shaft 102 of a photoconductor 101 and a driving shaft 103 are arranged in parallel, and a gear 104 provided at one end of the photoconductor 101 is connected to a driving gear 10 of the driving shaft 103.
5 and is connected. The second scheme is
As shown in FIG. 8, the rotation shaft 102 of the photoconductor 101 and the drive shaft 103 are arranged on the same axis, and a claw 106 is provided at one end of the rotation shaft 102 of the photoconductor 101, while a claw 107 is provided at one end of the drive shaft 103. Is provided so as to be biased toward the photoconductor 101 by a spring 109, and the claws 106 of the photoconductor 101 are engaged with the claws 107 of the sleeve 108 of the drive shaft 103 to be connected. In the third method, as shown in JP-A-63-8655, the rotating shaft and the driving shaft of the photosensitive member are arranged on a coaxial line, a male screw is formed at one end of the rotating shaft of the photosensitive member, and the other end is formed at the other end. In this method, a spring for urging the photoconductor in the axial direction is provided, and a male screw of the photoconductor is screwed and connected to a female screw formed at one end of the drive shaft.

[0004]

SUMMARY OF THE INVENTION
In the first method, the connection / removal of the connection between the photosensitive member 101 and the drive shaft 103 is good, but the pitch unevenness caused by the one-pitch meshing accuracy of the gears 104 and 105 and the color misregistration caused by the total meshing error. There is a problem that image noise appears and a high-quality image cannot be obtained. In addition, the second
In the method (1), the connection and disconnection of the photosensitive member 101 and the drive shaft 103 is good, as in the first method.
Even if the members 107 are connected to each other, if the shaft is eccentric between the photosensitive member 101 and the drive shaft 103, there is a problem in that the photosensitive member 101 may have uneven rotation, causing a color shift in an image. Further, in the third method, although the rotation transmission accuracy is high, it is necessary to make the spring force of the spring provided on the photoreceptor larger than the frictional force of the cleaning member and each seal member that comes into contact with the photoreceptor as well as the weight of the photoreceptor. Therefore, there is a problem that a large operation force is required when the photosensitive member is pushed into the apparatus, and the operability is not preferable.

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and has as its object to provide a drive coupling device having high-precision rotation transmission and good operability at the time of attachment and detachment, and an image forming apparatus using the same. It is an issue.

[0006]

According to the present invention, there is provided a drive connecting device for rotatably connecting a driven member to a drive member, wherein the drive member is axially movable with respect to the drive member. A connection member provided on at least one of the drive member and the connection member, and an axial restriction member for restricting an axial movement amount of the connection member; and at least one of the drive member and the connection member. A rotation direction regulating member provided on one of the members, for regulating movement of the connecting member in the rotational direction, an urging means for urging the connecting member to contact the axial direction regulating member, and the driven member Driven member restricting means for restricting the movement of the driven member in the direction, positioning means for aligning the axis of the driven member with the axis of the driving member, and rotation of the driving member More said connecting member is brought into contact with said axial restriction member, and the one having a pressing means for abutting at least one of the driven member to the driving member or the axial direction regulating member.

In the configuration of the present invention, when the driven member is brought close to the driving member and the driving member is rotated, the rotational force of the driving member is converted into an axial pressing force on the connecting member and the driven member by the pressing means. You. Thus, the connecting member comes into contact with the axial direction regulating member, and the driven member comes into contact with at least one of the driving member and the axial direction regulating member. As a result, the driving member and the connecting member are integrated via the axial regulating member, and the connecting member and the driven member are integrated, and as a result, the driving member and the driven member are integrated. Therefore, the rotation of the driving member is transmitted to the driven member with high accuracy. Also, the driven member is brought close to the driving member,
By simply rotating the driven member, the driving member and the driven member are integrally connected, so that there is no need to press the driven member toward the driving member, and the urging force of the urging means for urging the connecting member is reduced. It is small and operability is good.

[0008] It is preferable that the connecting member is a cylindrical sleeve provided on the driving member.

Preferably, the axial direction regulating member is a projection fixed to the driving member, and the projection is preferably engaged with a notch formed on an end face of the connecting member. Alternatively, it is preferable that the axial direction regulating member is a flange formed on an outer peripheral surface of the driving member, and the flange is in surface contact with an end surface of the connecting member. Alternatively, the axial restriction member is
It comprises a projection fixed to the driving member and a ring externally provided on the driving member, wherein the projection is engaged with a notch formed on an end face of the connection member, and the ring is connected to an end face of the connection member. Surface contact is preferred.

It is preferable that the rotation direction regulating member is a projection fixed to the driving member, and the projection is fitted in a notch formed in an axial direction from an end surface of the connecting member.

The driven member restricting means comprises a leading end of the driving member and a deepest portion of a connecting hole formed in an end face of the driven member. It is preferable to restrict the movement of the driven member in the axial direction by contacting the driven member.

Preferably, the positioning means comprises a tapered surface formed at the tip of the driving member and a tapered hole formed at the end surface of the driven member.

It is preferable that the pressing means is composed of a male screw formed on an outer peripheral surface of the connecting member and a female screw formed on an inner peripheral surface of a connecting hole formed on an end surface of the driven member.

According to another aspect of the present invention, there is provided a cylindrical electrostatic latent image carrier which is a driven member rotatably connected by a driving member, and the electrostatic latent image carrier. Latent image forming means for forming a latent image corresponding to the image,
And a means for developing a latent image formed on the electrostatic latent image carrier, as a drive connection device that rotatably connects the driven member to the drive member,
The drive coupling device is used.

According to this image forming apparatus, since the drive connecting device having high-precision rotation transmission is used for connecting the electrostatic latent image carrier and the driving member, an image having no rotation unevenness and no color shift is provided. Can be formed.

[0016]

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

FIG. 1 shows a tandem-type full-color printer which is an embodiment of an image forming apparatus using a drive connecting device according to the present invention for a photosensitive drum. This printer is
The paper feeding / conveying unit 1 includes an exposure unit 2, a developing unit 3, an intermediate transfer unit 4, a transfer unit 5, and a fixing / discharge unit 6. Note that, of these components, the exposure unit 2 and the development unit 3
And the intermediate transfer unit 4 includes yellow, magenta, cyan,
Each of the image forming stations Y, M, C, and K for each color of black is provided.

The above-mentioned components are well known and will be briefly described here. First, the paper feeding / transporting unit 1 includes a cassette 7
The sheet 8 accommodated in the printer 1 is fed one by one by a feed roller 9, and is conveyed to the transfer unit 5 via a conveying roller 10 a.
The exposure unit 2 forms a latent image on the photoconductor 11 based on the image. The developing unit 3 develops the latent image formed on the photoreceptor 11 using toner and makes the latent image visible. The intermediate transfer section 4 applies the toner image elicited on the photoconductor 11 to the roller 1.
Intermediate transfer belt 13 supported by 2a, 12b, 12c
The primary transfer is performed thereon. The transfer section 5 secondarily transfers the toner image on the intermediate transfer belt 13 to the sheet 8. Fixing / ejection unit 6
Fixes the toner image transferred onto the sheet 8 and discharges the sheet 8 onto the discharge tray 14 via the transport roller 10b.

The photosensitive member 11 is composed of a cylindrical drum, and as shown in FIG.
5 and 16 are rotatably supported between a front frame 18 and a rear frame 19 of the frame 17, and a photoconductor assembly 20 is provided.
It is configured as This photoconductor assembly 20 includes:
The front frame 18 is housed in the main body so as to overlap or be flush with the main body front frame 21 of the printer, and is pulled out of the main body along the guide rail (not shown) in the direction of arrow a, and in the direction of arrow b. It can be pushed into the body and positioned and fixed by the pins 22.

The photosensitive member 11 is driven by a drive unit 24 provided on a rear frame 23 of the main body. The drive unit 24 includes a motor 25
A drive shaft 3 having an intermediate shaft 28 having a first reduction gear 27 meshed with a pinion 26 of the motor 25 and a third reduction gear 30 meshing with a second reduction gear 29 of the intermediate shaft 28
1 is supported on a frame 32. Drive shaft 31
Has a flywheel 33 at one end, and is connected to the rotating shaft 16 of the photoreceptor 11 via a drive connecting device 34 according to the present invention.

The drive connecting device 34 separates the rotating shaft 16 of the photosensitive member 11 from the drive shaft 31 of the drive unit 24 when the photosensitive member assembly 20 is pulled out from the printer body, and also connects the photosensitive member assembly 20 to the printer body. When pushed, the rotating shaft 16 of the photoconductor 11 is connected to the driving shaft 31 so as to be rotatable. Therefore, the drive member of the drive connection device 34 of the present invention is the drive shaft 31 of the drive unit 24, and the driven member is the rotation shaft 16 of the photoconductor 11.

The drive connecting device 34 has a connecting sleeve 35 as a connecting member as shown in FIG.
The connecting sleeve 35 is cylindrical and is externally movably mounted on an end of the drive shaft 31. Connecting sleeve 3
At one end of 5, a plurality of V-shaped notches 36, preferably 3
U-shaped notch 3 extending in the axial direction at the other end
7 are formed. On the outer peripheral surface of the drive shaft 31, a drive pin 38 as an axial direction regulating member for regulating an axial movement amount of the connection sleeve 35 is engaged so as to engage with the V-shaped notch 36 of the connection sleeve 35. The projections are provided in the direction perpendicular to the core by the number corresponding to the notches 36. Further, the U-shaped notch 37 of the connection sleeve 35 is used.
On the outer peripheral surface of the drive shaft 31, a guide pin 39 serving as a rotation direction regulating member for regulating the movement of the coupling sleeve 35 in the rotational direction is provided so as to protrude in a direction perpendicular to the axis. I have. The drive pin 38 and the guide pin 39
Instead of being provided on the drive shaft 31, it may be provided on the coupling sleeve 35 so as to slide in the axial groove provided on the drive shaft 31.

The drive shaft 31 between the end surface of the connection sleeve 35 and the retaining ring 40 attached to the drive shaft 31 has a coil as biasing means for biasing the connection sleeve 35 so as to contact the drive pin 38. A spring 41 is provided. An external thread 42 is formed on the outer peripheral surface of the connection sleeve 35. The male screw 42, together with the female screw 46 of the rotating shaft 16 of the photoreceptor 11, which will be described later, causes the connecting sleeve 35 to abut on the drive pin 38 by the rotation of the drive shaft 31, and
This constitutes a pressing means for bringing the photoconductor 11 into contact with the tip of the drive shaft 31. A tapered tapered surface 43 is formed at the tip of the drive shaft 31. This tapered surface 43
Together with the tapered hole 47 of the rotating shaft 16 of the photoreceptor 11, which will be described later, constitutes a positioning means for making the axis of the photoreceptor 11 coincide with the axis of the drive shaft 31. The distal end of the drive shaft 31 is connected to a tapered hole 4 of a rotation shaft 16 of the photosensitive member 11 described later.
Together with the deepest part 48 of 7, a driven member regulating means for regulating the movement of the photoconductor 11 in the direction of the drive shaft 16 is constituted.

A flange 44 is inserted into and fixed to one end of the photoconductor 11, and a rotating shaft 16 is protruded from an end surface of the flange 44 in the axial direction of the photoconductor 11. This rotating shaft 1
6, a connection hole 45 having the same axis as the photoconductor 11 is formed. On the inner peripheral surface of the connection hole 45, a female screw 46 to be screwed with the male screw 42 of the connection sleeve 35 is formed. The direction of the female screw 46 is
Is rotated in the rotation direction at the time of image formation.
In the direction in which it is screwed into the male screw 42. Connection hole 45
A tapered hole 47 is formed at the back of the photoconductor 11, and the deepest portion 48 of the tapered hole 47 is located on the axis of the photoconductor 11.

Next, the drive coupling device 34 having the above-described configuration is used.
The operation of will be described.

First, the operation of connecting the rotating shaft 16 of the photoconductor 11 to the drive shaft 31 when the photoconductor assembly 20 pulled out from the printer main body is pushed into the main body will be described. As shown in FIG. 3, the rotation shaft 16 of the photoconductor 11 approaches the drive shaft 31 as the photoconductor assembly 20 is pushed. Even if the axis of the rotation shaft 16 of the photoconductor 11 is slightly displaced from the axis of the drive shaft 31, the edge of the connection hole 45 of the rotation shaft 16 of the photoconductor 11 has the tapered surface 43 at the tip of the drive shaft 31. 4A, the rotating shaft 1 of the photoconductor 11 is attached to the tip of the driving shaft 31 as shown in FIG.
The 6 connection holes 45 are fitted. At this time, since the end face of the connection sleeve 35 is pressed against the edge of the connection hole 45 of the photoconductor 11, the connection sleeve 35 retreats rightward in FIG. This allows
The front frame 18 of the photoconductor assembly 20 is fixed at a regular position with respect to the main body front frame 21. As described above, when the photoreceptor assembly 20 is pushed into the main body, the photoreceptor 11 can be driven by the drive shaft 31 as in the related art, because the force only needs to overcome the urging force of the coil spring 41 of the coupling sleeve 35.
This eliminates the need to press with a strong force, thereby improving operability.

When a sensor (not shown) detects that the front frame 18 of the photoreceptor assembly 20 is fixed at a proper position with respect to the main body front frame 21, the motor 25 of the drive unit 24 is driven based on this detection signal. Then, the drive shaft 31 rotates in the direction of the arrow in FIG. 4A via the first, second, and third reduction gears 27, 29, and 30. At this time, the coupling sleeve 35 rotates in the same direction as the drive shaft 31 via the guide pin 39. As a result, the male screw 42 on the outer peripheral surface of the coupling sleeve 35 urged toward the photoconductor 11 by the coil spring 41 and the rotating shaft 16 of the photoconductor 11
The engagement of the connection hole 45 with the internal thread 46 of the connection shaft 45 starts, and the connection sleeve 35 moves in the axial direction toward the tip of the drive shaft 31 while being screwed into the connection hole 45 of the rotating shaft 16 of the photoconductor 11. When the V-shaped notch 36 at the end of the connecting sleeve 35 comes into contact with the drive pin 38, further movement of the connecting sleeve 35 is restricted. As a result, with the rotation of the coupling sleeve 35 whose movement in the axial direction is restricted, the photosensitive member 1 is rotated.
One rotation shaft 16 moves in the axial direction toward the drive shaft 31. At this time, even if the axis of the rotation shaft 16 of the photoconductor 11 is slightly shifted from the axis of the drive shaft 31, the drive shaft 31 is inserted into the tapered hole 47 of the connection hole 45 of the rotation shaft 16 of the photoconductor 11. Since the leading end is guided, the axis of the rotating shaft 16 of the photoconductor 11 coincides with the axis of the driving shaft 31. Eventually,
As shown in FIG. 4B, the deepest portion 48 of the tapered hole 47 of the photoconductor 11 contacts the tip of the drive shaft 31 and
Is further restricted in the axial direction, and the rotation shaft 16 and the drive shaft 31 of the photoconductor 11 are firmly connected on the same axis. As a result, the torque of the drive shaft 31 is
Is transmitted to the rotating shaft 16 of the photoreceptor 11 with good rotation transmission accuracy, and the photoreceptor 11 is driven to rotate, so that a good image without image unevenness and color shift can be formed.

Next, a description will be given of the operation when the connection between the rotation shaft 16 of the photoconductor 11 and the drive shaft 31 is released in order to pull out the photoconductor assembly 20 from the printer body. For this purpose, for example, a disconnection switch may be provided on the main body, and the user may first press the disconnection switch before pulling out the photoconductor assembly 20 from the main body. When the disconnection switch is pressed, the motor 25 of the drive unit 24 is driven to rotate in the reverse direction based on this signal, and the drive shaft 31 rotates in the reverse direction. As a result, the operation is the reverse of the connection,
The connection between the rotation shaft 16 of the photoconductor 11 and the drive shaft 31 is released. That is, the connection sleeve 35 is rotated in the reverse direction by the reverse rotation of the drive shaft 31, and accordingly, the rotating shaft 1 of the photoconductor 11 is first rotated.
The deepest portion 48 of the sixth tapered hole 47 is separated from the tip of the drive shaft 31, and then the connecting sleeve 35 is retracted, and the connection between the rotating shaft 16 of the photoconductor 11 and the drive shaft 31 is released. Thereby, the photoreceptor assembly 20 can be pulled out from the main body.

FIG. 5 shows a modified example of the drive coupling device 34. This drive coupling device 34 is provided with an annular flange 50 instead of the drive pin 38 which is an axial direction regulating member shown in FIG. 3, and the flange 50 has a tapered surface 51 facing the end surface of the coupling sleeve 35. It is formed. According to the drive coupling device 34, the tapered surface 51 of the flange 50 and the end surface of the coupling sleeve 35 are in surface contact with each other, so that the frictional contact between them makes the torque of the drive shaft 31 to the coupling sleeve 35 more accurate. Communication is performed.

FIG. 6 shows another modification of the connecting device 34. This coupling device 34 is provided with a drive pin 38 and a ring 52 instead of the drive pin 38 which is an axial direction regulating member shown in FIG. One end face of the ring 52 is formed with a V-shaped notch 53 for engaging the drive pin 38, and the other end face is formed with a tapered face 54 facing the end face of the coupling sleeve 35. The drive connecting device 34 can be used when the flange 50 cannot be formed as in the drive connecting device 34 of FIG. According to the drive connecting device 34, like the drive connecting device 34 of FIG.
Since the tapered surface 54 of the ring 52 is in surface contact with the end surface of the connection sleeve 35, the frictional contact between them allows more accurate transmission of torque from the drive shaft 31 to the connection sleeve 35.

The exposure unit 2 in the above embodiment is
A solid scanning print head such as an LED or a laser scanning print head can be used.

The relationship between the tapered hole 47 of the photosensitive member 11 and the tapered surface 43 of the drive shaft 31 is reversed.
A conical projection may be provided at the bottom of one connection hole 45, and a tapered hole for receiving the projection may be provided on the tip end surface of the drive shaft. Further, these do not necessarily have to be tapered, and may be such that the end surface of the drive shaft is made flat and the outer periphery thereof is chamfered.

In the above-described embodiment, the drive connection device according to the present invention is applied to a full-color printer, but it is needless to say that the drive connection device can also be applied to a monochrome printer, an LED printer, and the like.

[0034]

As is apparent from the above description, according to the drive coupling device of the present invention, high-precision rotation transmission and good operability can be obtained. Further, according to the image forming apparatus of the present invention, it is possible to form an image without rotation unevenness and without color shift.

[Brief description of the drawings]

FIG. 1 is a schematic view of a tandem-type full-color printer as an embodiment of an image forming apparatus using a drive connection device according to the present invention for a photosensitive drum.

FIG. 2 is a sectional view showing a photoreceptor assembly of the printer of FIG. 1 and a drive unit thereof.

FIG. 3 is a cross-sectional view of a drive connection device between a rotation shaft of the photoconductor and a drive shaft.

FIG. 4 is a cross-sectional view showing a state in which the drive connection device of FIG.

FIG. 5 is a cross-sectional view showing a modification of the drive coupling device of FIG. 3;

FIG. 6 is a cross-sectional view showing another modified example of the drive connection device of FIG. 3;

FIG. 7 is a diagram showing an example of a conventional drive connection device.

FIG. 8 is a view showing another example of a conventional drive coupling device.

[Explanation of symbols]

Reference Signs List 11 photoconductor (driven member) 31 drive shaft (drive member) 34 drive connection device 35 connection sleeve (connection member) 38, 50, 52 drive pin, flange, ring (axial direction restriction member) 39 guide pin (rotation direction) 40, retaining ring 41 coil spring (biasing means) 42, 46 male screw, female screw (pressing means) 43, 47 tapered surface, tapered hole (positioning means) 48 deepest part (driven member regulating means)

Claims (10)

[Claims] 1. A drive connecting device for rotatably connecting a driven member to a drive member, comprising: a connecting member provided on the drive member so as to be movable in an axial direction; An axial regulating member provided on at least one of the first and second members, for regulating an axial movement amount of the connecting member; and an axial regulating member provided on at least one of the driving member and the connecting member to move the connecting member in the rotational direction. A rotation direction regulating member for regulating, an urging means for urging the connecting member so as to contact the axial direction regulating member, and a driven member regulating member for regulating movement of the driven member in the direction of the driving member. Means, positioning means for aligning the axis of the driven member with the axis of the driving member, and rotating the driving member so that the connecting member abuts on the axial regulating member. And drive connection apparatus characterized by having a pressing means for abutting said driven member to at least one of the driving member or said axial restriction member. 2. The drive connection device according to claim 1, wherein the connection member is a cylindrical sleeve externally mounted on the drive member. 3. The drive coupling device according to claim 1, wherein the axial direction regulating member is a projection fixed to the driving member, and the projection is engaged with a notch formed on an end surface of the coupling member. 4. The drive coupling device according to claim 1, wherein the axial direction regulating member is a flange formed on an outer peripheral surface of the driving member, and the flange is in surface contact with an end surface of the coupling member. 5. The axial direction regulating member comprises a projection fixed to the driving member and a ring provided on the driving member, and the projection is engaged with a notch formed on an end face of the connecting member. The drive coupling device according to claim 1, wherein the ring is in surface contact with an end surface of the coupling member. 6. The rotation direction regulating member is a projection fixed to the driving member, and the projection is fitted into a notch formed in an axial direction from an end surface of the connecting member.
4. The drive coupling device according to claim 1. 7. The driven member restricting means comprises a tip of a driving member and a deepest portion of a connection hole formed in an end surface of the driven member, wherein the deepest portion of the connection hole of the driven member is a driving member. The drive coupling device according to claim 1, wherein the drive connection device restricts axial movement of the driven member by abutting on a tip of the drive member. 8. The drive coupling device according to claim 1, wherein the positioning means comprises a tapered surface formed at a distal end of the driving member and a tapered hole formed at an end surface of the driven member. 9. The pressing means comprises a male screw formed on an outer peripheral surface of a connecting member and a female screw formed on an inner peripheral surface of a connecting hole formed on an end surface of a driven member. 2. The drive coupling device according to claim 1. 10. A cylindrical electrostatic latent image carrier as a driven member rotatably connected by a driving member,
An image forming apparatus comprising: a latent image forming unit that forms a latent image corresponding to an image on the electrostatic latent image carrier; and a unit that develops a latent image formed on the electrostatic latent image carrier. An image forming apparatus using the drive connecting device according to any one of claims 1 to 9 as a drive connecting device that rotatably connects a driven member to a member.