JP2016017992A - Rotating body driving device and image forming apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a rotating body driving device capable of suppressing the occurrence of fluctuation in rotational speed and the occurrence of vibration in a rotating body and a driving source due to a deflection angle between the rotary shaft of the rotating body and the driving shaft of the driving source, with inexpensive and simple structure.SOLUTION: A rotating body driving device 50 is provided that includes a rotating body 1 and a driving shaft 51a for rotationally driving the rotating body 1 with driving force from a driving source 51, and that rotates the rotating body by connecting and fixing a rotary shaft 1a of the rotating body and the driving shaft. The driving source is fixed to an image forming apparatus body through a support member 70 being an elastic body. The support member has a single plate shape and includes torsion parts 71a, 71b, 72a, 72b having lower torsional rigidity than rigidities of the rotary shaft, the driving shaft and support places 101, 102 of the image forming apparatus body supporting the rotary shaft and the driving shaft, and the support member can deform in a torsion direction.SELECTED DRAWING: Figure 5

Description

  The present invention relates to a rotating body driving device that transmits a driving force from a driving source to drive a rotating body, and an image forming apparatus such as a printer, a facsimile machine, and a copying machine that includes the rotating body driving device.

Conventionally, various shaft couplings have been used to absorb the deflection angle between the shafts when the transmission shaft and the transmission shaft are connected and fixed. For example, in Patent Document 1, the following flexible shaft is used. Joints have been proposed.
The flexible shaft coupling includes a hub having a cylindrical hub body to which the transmission shaft is coupled and two approximately 180-degree arc-shaped leaf springs for each transmission shaft.
The hub body has one end in the axial direction of the hub body connected to the transmission shaft, and two arc springs at the other end. Specifically, the small-diameter end faces of the two arc-shaped leaf springs face the circumference of the hub body on the cylindrical end faces and the circumferential surface of the hub body, and are Two arc-shaped leaf springs are provided so as to leave a gap in the radial direction. The hub body is coupled to one end side in the circumferential direction on the small-diameter end face of each of the two arc-shaped leaf springs.

The two hubs of the flexible shaft joint have the same configuration, and of the cylindrical end faces of the hub body provided in the hub, the end faces on the end side having the leaf springs in the axial direction are mutually axial. It is provided so as to face each other with a gap.
The two leaf springs provided in one hub are connected to the hub body of the circumferential end not connected to the hub body and the two leaf springs provided in the other hub. The other end portion in the circumferential direction is joined, and the entire flexible shaft coupling is integrally formed.

In the flexible shaft joint configured as described above, the first leaf spring and the second leaf spring which are alternately combined in the torque transmitting portion are deformed by the elastic deformation accompanied by the axial deflection and slight torsional deformation. It is said that the declination can be adjusted.
Patent Document 2 proposes a rotary shaft coupling in which rubber or resin is foam-filled inside a helical metallic elastic member in order to suppress the deflection angle and vibration due to the deflection angle. There has also been proposed a rotary shaft coupling in which a vibration damping layer is formed by immersing, coating, or spraying uncured rubber or resin on the surface of a metallic elastic member. According to these, the declination is absorbed by the elasticity of the metallic elastic member, and the vibration generated in the rotary shaft joint can be absorbed by the vibration damping layer.

An electrophotographic image forming apparatus includes a rotating body such as a photoconductor and a developing roller, and rotates the rotating body to form an image. As this type of image forming apparatus, a driving source for driving the rotating body is fixed inside the image forming apparatus, and a driving shaft of the driving source and a rotating shaft of the rotating body are connected and fixed, whereby the rotating body is fixed. 2. Description of the Related Art An image forming apparatus including a rotating body driving device that rotates is known.
When the rotating shaft of the rotating body and the drive shaft of the driving source are fixed, if the axis of the rotating shaft of the rotating body and the driving shaft of the driving source is fixed in a declined state, the rotating body and the driving source Variations in the rotational speed and vibration of the drive shaft may occur, affecting the printing process such as exposure and transfer, and may adversely affect print quality.

  However, when the flexible shaft coupling of Patent Document 1 is used to absorb this declination, the configuration of the flexible shaft coupling is complicated, resulting in a problem that the manufacturing cost increases. Moreover, in order to absorb this declination, when the rotating shaft coupling of patent document 2 is used, multiple parts which comprise a rotating shaft coupling are needed, or manufacturing processes, such as immersion and application | coating, are needed. In addition, difficulty in manufacturing a container filled with rubber or resin is also expected, and there is a problem that the cost of parts and manufacturing costs associated with these increase.

  The present invention has been made in view of the above-described problems, and its object is to reduce the rotational speed fluctuation and vibration of the rotating body and the driving source due to the deviation angle between the rotating shaft of the rotating body and the driving shaft of the driving source. An object of the present invention is to provide a rotating body drive device that can be suppressed with an inexpensive and simple structure.

In order to achieve the above object, the present invention includes a rotating body and a driving shaft that rotates by receiving a driving force from a driving source, and the rotating shaft of the rotating body and the driving shaft are coupled and fixed. In the rotating body drive device for rotating the rotating body,
The drive source is fixed to the image forming apparatus main body via a support member that is an elastic body, and the support member supports the rotating shaft and the drive shaft. And a plurality of torsion portions having a torsional rigidity lower than that of the drive shaft, and the support member is deformable in a twisting direction with respect to the rotation shaft.

  ADVANTAGE OF THE INVENTION According to this invention, generation | occurrence | production of the rotational speed fluctuation | variation and vibration of a rotary body and a drive source by the deflection | deviation angle of the rotary shaft of a rotary body and the drive shaft of a drive source can be suppressed with an inexpensive and simple structure.

1 is a schematic configuration diagram illustrating a printer according to an embodiment. It is a schematic diagram which shows the conventional rotary body drive device. It is a schematic diagram which shows the case where the angle accuracy of the attachment surface of the drive source in the conventional rotary body drive device is not ensured. It is a schematic diagram which shows the structure of the rotary body drive device with which the printer which concerns on this embodiment was equipped. It is the schematic diagram which looked at the supporting member which the rotary body drive device has from the direction of arrow C shown in FIG.

Hereinafter, an embodiment in which the present invention is applied to a printer which is an electrophotographic image forming apparatus will be described with reference to the drawings.
First, an overall outline of the printer according to the present embodiment will be described. In the printer, those not conventionally mentioned as constituent elements of the present invention (constituent members) can be conventionally known ones.
FIG. 1 is a schematic configuration diagram illustrating a printer 100 which is an image forming apparatus according to the present embodiment.
In FIG. 1, a printer 100 forms an image on a transfer material (for example, recording paper) by an intermediate transfer method using a transfer belt 21. The printer 100 includes a transfer unit 20. The transfer means 20 stretches an endless transfer belt 21 by a plurality of rollers disposed inside the belt loop. The transfer belt 21 is moved endlessly in the clockwise direction in the figure by a transfer belt drive roller 22 that is rotated by a drive mechanism (not shown). Above the transfer belt 21, four process cartridges 10Y, 10M, 10C, and 10K for forming yellow, magenta, cyan, and black toner images are disposed along the surface movement direction of the transfer belt 21. ing. Hereinafter, Y, M, and C that are color-coded codes are omitted as appropriate.

  Each process cartridge 10 is provided with a photoreceptor 1. Each photoconductor 1 is rotationally driven in a counterclockwise direction in the drawing by a driving mechanism (not shown). A known charging unit, developing unit, and cleaning device (not shown) are provided around each photoconductor 1. An optical writing unit (not shown) is provided above the four process cartridges 10.

While the photoconductor 1 rotates counterclockwise in the figure, the surface thereof is uniformly charged by the charging means, and the uniformly charged surface of the photoconductor 1 is irradiated with laser light by an optical writing unit (not shown). As a result, an electrostatic latent image is carried. This electrostatic latent image is developed by the developing means to become a toner image.
A primary transfer roller 23 is arranged at a position facing the Y, M, C, and K photoconductors with the transfer belt 21 interposed therebetween to form a primary transfer nip. The Y, M, C, and K toner images respectively developed on the Y, M, C, and K photoconductors are primarily transferred onto the surface of the transfer belt 21 at the primary transfer nip.

On the downstream side of the transfer direction of the transfer belt 21 from the primary transfer nip, the secondary transfer roller 31 is in contact with the opposing roller 24 across the transfer belt 21 to form a secondary transfer nip. The toner image on the transfer belt 21 is secondarily transferred collectively to the transfer material 2 fed to the secondary transfer nip.
After the transfer material 2 is conveyed from the right side to the left side in the drawing by the secondary transfer roller 31, the toner image is fixed on the surface by the fixing unit 32. The fixing unit 32 fixes the toner image on the surface of the transfer material by pressing the heating roller against the transfer material while heating the heating roller at the nip between the heating roller 33 and the pressure roller 34.

  As a rotating body driving device (not shown) that rotates the photosensitive member 1, the transfer belt driving roller 22, and the like, an axis of a driving shaft of a driving motor that is a driving source and an axis of a rotating shaft of a rotating body that is a driven component are included. A system is employed in which the rotating body is driven by being connected to be connected on a coaxial line. This method vibrates the rotating body, which is a driven component, due to vibration in the speed reduction mechanism (for example, vibration at the time of meshing of teeth between gears) that occurs when a mechanism that decelerates using gears, belts, etc. is provided. This is a measure for preventing the image formation from adversely affecting the image formation.

Next, the configuration of the conventional rotating body driving device 50 will be described with reference to the drawings.
FIG. 2 is a schematic diagram showing a conventional rotating body driving device 50.
The photosensitive member 1 as a rotating body has a rotating shaft 1 a rotatably held via a bearing 101 a provided on an apparatus main body member 101 shown schematically in the image forming apparatus 100. The end of the rotating shaft 1 a of the photoreceptor 1 is fixed to the end 60 a of the joint 60. The other end 60b of the joint 60 fixes a drive shaft 51a of a drive motor 51 that is a drive source.
The drive motor 51 is fixed to a mounting surface 102 a of the apparatus main body member 102 shown schematically by a drive motor fixing screw 52. In the rotating body driving device 50 shown in FIG. 2, since the angle accuracy of the mounting surface 102a is ensured, the axis of the rotating shaft 1a of the photosensitive member 1 and the driving shaft 51a of the driving motor 51 are on the same axis. Is provided.

FIG. 3 is a schematic diagram showing a case where the angle accuracy of the mounting surface 102a of the apparatus main body member 102 of the conventional rotating body driving device 50 is not ensured. In FIG. 3, the inclination of the mounting surface 102a of the apparatus main body member 102 is emphasized. Further, the YZ coordinates shown in FIG. 3 indicate the axis of the rotating shaft 1a of the photosensitive member 1 as the Z axis and the vertical direction with respect to the axis of the rotating shaft 1a of the photosensitive member 1 as the Y axis.
The rotating body driving device 50 shown in FIG. 3 has the same configuration as the rotating body driving device 50 shown in FIG. 2 except for the angular accuracy of the mounting surface 102a of the apparatus main body member 102 and the joint 61 described later. Description is omitted.
In the conventional rotating body driving device shown in FIGS. 2 and 3, an example in which a photosensitive member is used as the rotating body has been described. However, the rotating shaft is connected and fixed to the driving shaft of the driving source to be driven to rotate. The rotating body is not limited to this.

As shown in FIG. 3, when the angle accuracy of the mounting surface 102a of the apparatus main body member 102 of the image forming apparatus is not ensured, the axis of the rotating shaft 1a of the photoreceptor 1 and the driving shaft 51a of the driving motor 51 are coaxial. In other words, the axis of the rotating shaft 1a of the photosensitive member 1 and the driving shaft 51a of the driving motor 51 are fixed in a state where they have an angle (declined).
As described above, when the axis of rotation of the rotating shaft 1a of the photosensitive member 1 and the driving shaft 51a of the driving motor 51 are fixed in a deviated state, they are indicated by arrows A and B in the drawing at the time of rotational driving or driving standby. As shown in the drawing, a load in a direction of bending from each shaft end toward each center occurs with respect to the rotating shaft of the rotating body and the driving shaft of the driving source. This load causes rotational speed fluctuations and vibrations of the rotating body and the driving shaft of the driving source, which may affect the printing process such as exposure and transfer, and adversely affect printing quality.

  The mounting surface 102a for fixing the drive motor 51 to the apparatus main body is such that the drive shaft 51a of the drive motor 51 is in the axial direction of the rotary shaft 1a of the photosensitive member 1 as in the rotary body drive device 50 shown in FIG. Ideally, the angle accuracy should be ensured so as to be on the coaxial line. However, as shown in FIG. 3, if this angular accuracy is not maintained, the axis of the rotating shaft 1a of the photosensitive member 1 and the driving shaft 51a of the driving motor 51 are not coaxial, and the rotating shaft of the photosensitive member 1 There is a declination between 1a and the drive shaft 51a of the drive motor 51.

  The cause of the deviation between the rotation shaft 1a of the photosensitive member 1 and the drive shaft 51a of the drive motor 51 is not limited to the case where the angle accuracy of the mounting surface 102a is not ensured. For example, the structure from the photoreceptor 1 to the drive motor 51 is generally composed of a combination of a plurality of parts, and the rotation shaft 1a of the photoreceptor 1 and the drive motor 51 are determined depending on the accuracy and assembly accuracy of the plurality of parts. It is difficult to fix the drive shaft 51a so that its axis is on the same axis. Further, due to the accuracy of the apparatus main body member 102 itself having the mounting surface 102a, it is difficult to fix the axis of the drive shaft 51a of the drive motor 51 to be coaxial with the axis of the rotation shaft 1a of the photoreceptor 1. It becomes.

  The conventional rotating body driving device 50 shown in FIG. 3 reduces the occurrence of loads in the direction of arrow A and the direction of arrow B generated on the rotating shaft 1a of the photosensitive member 1 and the driving shaft 51a of the driving motor 51 due to the declination. In order to achieve this, a joint 61 having elastic characteristics is used.

Next, an example in which the rotating body driving device according to the present invention is applied to a rotating body driving device that rotationally drives a photoconductor as a rotating body will be described with reference to the drawings.
FIG. 4 is a schematic diagram showing the configuration of the photosensitive member driving device in the present embodiment. In FIG. 4, the inclination of the mounting surface 102a of the apparatus main body member 102 is emphasized.

The rotating body driving device 50 is mainly composed of a photosensitive body 1 that is a rotating body, a driving motor 51 that is a driving source, and a support member 70 that fixes the driving motor 51.
The drive motor 51 is fixed to the support member 70 by a motor fixing screw 52, and the support member 70 is fixed to the attachment surface 102a of the apparatus main body member 102, so that it is indirectly fixed to the printer main body. In the present embodiment, the number of places where the drive motor 51 is fixed to the support member 70 is four, but the number of places fixed is not limited to this, depending on the specifications of the motor used.
The support member 70 is formed in a single plate shape, and the support member 70 is fixed to the attachment surface 102 a of the apparatus main body member 102 at two locations by support member fixing screws 53. The support member 70 is made of a SUS-based or copper-based metal material having an elastic property. The metal material preferably has a longitudinal elastic modulus of “phosphorus bronze (98E3 [N / mm2])” to “spring steel (206E3 [N / mm2]). This will be described in detail later.

Next, the support member 70 according to the present embodiment will be described in detail with reference to the drawings.
FIG. 5 is a schematic view of the support member 70 included in the rotating body driving device 50 as viewed from the direction of the arrow C shown in FIG.
The support member 70 includes a first fixing portion 74, a second fixing portion 76, a relay portion 75, a first twist portion that is a twist portion, and a second twist portion.
The first fixing portion 74 is an installation site for fixing the drive motor 51 to the support member 70, and is provided around the drive shaft hole 51 b for passing the drive shaft 51 a of the drive motor 51 and the drive shaft hole 51 b. There are four screw holes 52a for the motor fixing screw.

The relay portion 75 is provided with a gap with respect to the outer periphery of the first fixed portion 74 by two slits 73 a and 73 b provided on the inner peripheral surface of the relay portion 75. The two slits 73a and 74b form a pair of constricted portions 71a and 71b which are first twisted portions. The pair of constricted portions 71a and 71b form the inner peripheral surface of the relay portion 75 and the first fixing portion 74. Are joined. The relay portion 75 is coupled to a second fixing portion 76 described later by a pair of bridge portions 72 a and 72 b that are second twist portions provided on the outer peripheral surface of the relay portion 78.
The second fixing portion 76 is a fixing portion for fixing the support member 70 to the printer 100, and two fixing portions 76 a and 76 b that take a position with respect to the outer periphery of the relay portion 75 with a gap from the outer periphery. It consists of Each of the two fixing portions 76 a and 76 b has a screw hole 53 a for a supporting member fixing screw for fixing the supporting member 70 to the apparatus main body member 102.

In the present embodiment, four screw holes 52a for the motor fixing 52 are shown, but this is not restrictive depending on the specifications of the motor used. 5 shows two screw holes 53a for the fixing screw 53 for fixing the support member 70 to the apparatus main body member 102. However, depending on conditions such as the shape of the mounting surface 102a of the apparatus main body member 102, FIG. This is not the case.
Moreover, in this embodiment, although the 2nd fixing | fixed part 76 was comprised in two places of the fixing | fixed part 76a, 76b, it is not restricted to this. For example, the second fixing portion 76 may be provided so as to surround the outer periphery of the relay portion 75 with a gap.
In the present embodiment, the twisted portion of the support member 70 has a constricted shape such as the constricted portions 71a and 71b and the bridge portions 72a and 72b. However, the twisted portion in the support member of the present invention is not limited to this, and the twisted portion. It is sufficient that the torsional rigidity of the portion is lower than the rigidity of the apparatus main body member 101, the apparatus main body member 102, the rotating shaft 1a of the photosensitive member 1, and the driving shaft 51a. For example, the fixed portion 76 a may be formed in a rectangular shape, and the rectangular short side may be directly coupled to the relay portion 75.

Next, the operation of the support member 70 when the axis of the rotating shaft 1a of the photosensitive member 1 and the axis of the drive shaft 51a of the drive motor 51 are not on the same line (when a declination occurs) will be described.
The XY coordinates shown in FIG. 5 indicate the horizontal direction with respect to the axis of the rotating shaft 1a of the photoreceptor 1 as the X axis and the vertical direction as the Y axis.
When a declination that causes a load in the directions indicated by arrows A and B in FIG. 3 occurs, a load around the X axis in the XY coordinate axes shown in FIG. 5 is generated in the support member 70 via the drive shaft 51a. In the support member 70, deformation around the X axis occurs in the bridge portions 72a and 72b having the lowest torsional rigidity around the X axis. Due to the deformation of the bridge portions 72a and 72b around the X axis, the first fixing portion 74 coupled to the bridge portions 72a and 72b swings with respect to the rotation shaft 1a of the photosensitive member 1, and the rotation shaft 1a of the photosensitive member 1 is rotated. The deviation angle can be absorbed by adjusting the inclination of the drive shaft 51a of the drive motor 51 with respect to.

  Further, in the case of the declination in which a load around the Y axis in the XY coordinate axes shown in FIG. 5 is generated, a load around the Y axis is generated in the support member 70 via the drive shaft 51a. Deformation around the Y-axis occurs in the constricted portions 71a and 72b having low torsional rigidity. Due to the deformation of the constricted portions 71a and 72b around the Y axis, the relay portion 75 coupled to the constricted portions 71a and 72b and the first fixing portion 74 coupled to the relay portion 75 via the bridge portions 72a and 72b. Then, it swings around the Y axis with respect to the rotating shaft 1a of the photosensitive member 1. By the swing, the inclination of the drive shaft 51a of the drive motor 51 with respect to the rotation shaft 1a of the photoreceptor 1 can be adjusted, and the deviation angle can be absorbed.

  Further, in the case of a declination in which a load is generated in a direction other than the X-axis or the Y-axis in the XY coordinate axis shown in FIG. 5, each of the constricted portions 71a and 71b and the bridge portions 72a and 72b is deformed, The first fixed portion 74 swings with respect to the rotating shaft 1a of the photosensitive member 1, and the inclination of the driving shaft 51a of the driving motor 51 with respect to the rotating shaft 1a of the photosensitive member 1 can be adjusted to absorb the deviation angle. .

Here, if the axial direction of the rotating shaft 1a of the photosensitive member 1 is the Z-axis (not shown), a load around the Z-axis generated when the drive motor 51 is driven is generated on the support member 70 via the drive shaft 51a. At this time, a compressive load and a tensile load are applied to the constricted portions 71a and 71b and the bridge portions 72a and 72b of the support member 70 instead of a load due to torsion.
As a result of the inventors' sharp research, it has been found that the following problems arise when the declination is absorbed by using a joint formed of a rubber-based material or the like for the rotating body driving device. In other words, when a load around the rotating shaft of the rotating body such as the compression load and tensile load is applied to a joint formed of a rubber material or the like, the elasticity of the joint also works in the rotational direction of the drive shaft of the drive source. End up. For this reason, it became difficult to control the rotation of the drive source, and the rotation accuracy of the rotating body could not be ensured.

  On the other hand, the support member 70 used for the rotating body driving device 50 in the present embodiment has a single plate shape as a member used to absorb the declination, and therefore has high rigidity with respect to the rotation direction of the drive shaft 51a. The load of rotation control due to the compression load and the tensile load can be suppressed.

  As shown in FIG. 4, in the rotating body drive device 50 of the present invention, the drive motor 51 is fixed to the attachment surface 102 a of the device main body member 102 via the support member 70. The support member 70 is formed of a material having elastic characteristics, and absorbs the deflection angle between the rotating shaft 1a of the photosensitive member 1 and the driving shaft 51a of the driving motor as described above due to the elastic property. . Therefore, the rotating shaft 1a of the photosensitive member 1 which is a rotating member and the driving shaft 51a of the driving motor are fixed so that they are coaxial, and the rotating shaft 1a of the photosensitive member 1 and the driving shaft 51a of the driving motor 51 are bent. It is possible to reduce the generation of loads.

Further, in the rotating body driving device 50 of FIG. 4, the angle accuracy of the mounting surface 102a of the apparatus main body member 102 is not ensured as in the conventional rotating body driving device shown in FIG. However, unlike the rotating body drive device of FIG. 3, the drive motor 51 is fixed to the mounting surface 102a of the device body member 102 via the support member 70, so that the drive motor 51 is swung in accordance with the direction of the declination. Can move. Therefore, in the rotating body driving device 50 of the present embodiment shown in FIG. 4, the rotating shaft 1a of the photosensitive member 1 which is a rotating body and the driving shaft 51a of the driving motor are used regardless of the direction of the declination. It can be fixed so that the axis line is on the coaxial line.
Further, in the rotating body driving device 50 of the present embodiment, the deflection angle is absorbed by the support member 70 without using the elastic joint 61 like the conventional rotating body driving device 50 shown in FIG. The declination can be absorbed. Therefore, the joint can be formed in a simple shape with a simple cylindrical shape, and the cost can be reduced.

  Further, by using the above-mentioned metal material as the material for forming the support member 70, the rigidity against the compressive load and the tensile load in the rotation direction of the drive shaft 51a is increased as compared with the rubber-based material. Can do. Thereby, it becomes possible to perform rotational driving while suppressing vibration in the rotational direction of the drive shaft 51a, and it is possible to cope with a case where high-accuracy speed control is required when the drive motor 51 is driven.

In the present embodiment, the twisted portions are provided at a total of four locations including two locations that are symmetrical with respect to the drive shaft 51 a of the drive motor 51 and two locations that are orthogonal to the two locations. It was. Thereby, declination in all directions can be absorbed.
In addition, with such a configuration, when an angle between the rotation shaft of the rotating body and the drive shaft of the drive source occurs, only the torsion portion of the support member is deformed, and the drive motor together with the first fixing portion 74 51 can swing to absorb the declination.

  Moreover, in this embodiment, although the four twist parts were provided in the support member 70, if not only this but a pair of twist parts will be provided, the said deflection angle of one direction can be absorbed. For example, the support member 70 is fixed to the main body of the image forming apparatus by taking a position with a gap with respect to the outer periphery of the first fixing portion and the first fixing portion to which the driving source such as the driving motor 51 is fixed. It comprises the second fixed part. By connecting the outer peripheral surface of the first fixed portion and the inner peripheral surface of the second fixed portion with a pair of twisted portions that take positions symmetrical to the drive shaft of the drive source, the second fixed portion is connected to the drive source. It swings integrally and can absorb the deflection angle between the rotating shaft 1a of the photosensitive member 1 and the driving shaft 51a of the driving motor in any one direction.

What has been described above is merely an example, and the present invention has a specific effect for each of the following modes.
(Aspect A)
A rotating body such as the photosensitive member 1 and a driving shaft such as a driving shaft 51 a that rotates by receiving a driving force from a driving source such as the driving motor 51, and the rotating body such as the rotating shaft 1 a of the photosensitive member 1 rotates. In a rotary body drive device such as the rotary body drive device 50 that rotationally drives the rotary body by connecting and fixing the shaft and the drive shaft,
The drive source is fixed to the image forming apparatus main body via a support member such as a support member 70 that is an elastic body, and the support member is formed integrally as a whole and supports the rotating shaft and the drive shaft. The support portions of the image forming apparatus main body such as the apparatus main body members 101 and 102, the constricted portions 71a and 71b, the bridge portions 72a and 72b, etc. in which the torsional rigidity is lower than the rigidity of the rotating shaft and the driving shaft. A rotating body driving device having a twisted portion, wherein the support member is deformable in a twisting direction.

In this aspect, as described in the above embodiment, the declination between the rotation shaft 1a of the photosensitive member 1 and the drive shaft 51a of the drive motor can be absorbed by the elastic property of the support member 70. Thus, the drive motor 51 can be fixed so that the axis of the rotating shaft 1a of the photosensitive member 1 and the driving shaft 51a of the driving motor are on the same axis, and the driving of the rotating shaft 1a of the photosensitive member 1 and the driving motor 51 is possible. Generation | occurrence | production of the load which is going to bend the axis | shaft 51a can be reduced.
Further, since the deflection angle is absorbed by the support member 70, the deflection angle can be absorbed without using the elastic joint 61. Therefore, the joint can be a simple shape with a simple cylindrical shape, and the cost can be reduced.
Therefore, the rotational speed fluctuations of the rotating body such as the photosensitive member 1 and the driving source such as the driving motor due to the deviation angle between the rotating shaft of the rotating member such as the photosensitive member 1 and the driving shaft of the driving source such as the driving motor 51 or the like. Generation of vibration can be suppressed with an inexpensive and simple structure.

(Aspect B)
In Aspect A, the twisted portion is composed of a plurality of twisted portions, and the support member such as the support member 70 includes a first fixed portion such as a first fixed portion 74 to which the drive source such as the drive motor 51 is fixed. And a second fixing portion that is spaced from the outer periphery of the first fixing portion and is fixed to the main body of the image forming apparatus. The first fixing portion and the second fixing portion are And a pair of twisted portions.
According to this, as described in the above embodiment, the declination between the rotating shaft 1a of the photosensitive member 1 and the driving shaft 51a of the driving motor in any one direction is absorbed by the elastic property of the support member 70. be able to. Accordingly, the drive motor 51 can be fixed so that the axis of the rotation shaft 1a of the photoconductor 1 and the drive shaft 51a of the drive motor are on the same axis in any one direction. Moreover, generation | occurrence | production of the load which is going to bend the drive shaft 51a of the drive motor 51 can be reduced. Therefore, the driving of the rotating body such as the photosensitive member 1 and the driving motor is performed in an arbitrary direction by the deviation angle between the rotating shaft of the rotating body such as the photosensitive member 1 and the driving shaft of the driving source such as the driving motor 51. The fluctuation of the rotation speed of the source and the occurrence of vibration can be suppressed with an inexpensive and simple structure.

(Aspect C)
In Aspect A, the twisted portion is composed of a plurality of twisted portions, the support member such as the support member 70 has a single plate shape, and the first fixed portion 74 or the like to which the drive source is fixed is first. A fixing unit, a relay unit such as a relay unit 75 that surrounds the outer periphery of the first fixing unit with a gap, and a position with a gap with respect to the outer periphery of the relay unit are fixed to the image forming apparatus main body. A second fixing portion such as a second fixing portion 76, and the first fixing portion and the relay portion are coupled by a pair of first twisted portions such as constricted portions 71a and 71b, and the second fixing portion. The part and the relay part are coupled by a pair of second twisted parts such as bridge parts 72a and 72b, and the first twisted part and the second twisted part are the plurality of twisted parts.

In this aspect, as described in the above embodiment, the declination between the rotation shaft 1a of the photosensitive member 1 and the drive shaft 51a of the drive motor can be absorbed by the elastic property of the support member 70.
Specifically, when the horizontal direction with respect to the axis of the rotating shaft 1a of the photosensitive member 1 is the X axis and the vertical direction is the Y axis, the X axis is determined by the deviation angle between the rotating shaft 1a of the photosensitive member 1 and the driving shaft 51a of the driving motor. When a rotating load is generated, the load is transmitted to the support member 70 via the drive shaft 51a, and the bridge portions 72a and 72b having the lowest torsional rigidity around the X axis in the support member 70 are deformed around the X axis. Due to the deformation of the bridge portions 72a and 72b around the X axis, the first fixing portion 74 coupled to the bridge portions 72a and 72b swings with respect to the rotation shaft 1a of the photosensitive member 1, and the rotation shaft 1a of the photosensitive member 1 is rotated. The deviation angle can be absorbed by adjusting the inclination of the drive shaft 51a of the drive motor 51 with respect to.

Further, when a load around the Y axis is generated due to the deflection angle, this load is transmitted to the support member 70 via the drive shaft 51a, and the support member 70 has the lowest torsional rigidity around the Y axis at the constricted portions 71a and 72b. Deformation around the axis occurs. Due to the deformation of the constricted portions 71a and 72b around the Y axis, the relay portion 75 coupled to the constricted portions 71a and 72b, and the first fixing portion 74 coupled to the relay portion 75 and the bridge portions 72a and 72b, It swings around the Y axis with respect to the rotating shaft 1a of the photoreceptor 1. By this swing, the inclination of the drive shaft 51a of the drive motor 51 with respect to the rotation shaft 1a of the photoconductor 1 can be adjusted, and the deviation angle can be absorbed.
Further, when a load is generated in a direction that is neither the X axis nor the Y axis due to the declination, each of the constricted portions 71a and 71b and the bridge portions 72a and 72b is torsionally deformed, so that the rotation shaft 1a of the photosensitive member 1 is rotated. The first fixing portion 74 swings relative to the rotating shaft 1a of the photosensitive member 1, and the inclination of the driving shaft 51a of the driving motor 51 with respect to the rotating shaft 1a of the photosensitive member 1 can be adjusted to absorb the deviation angle.

  Furthermore, assuming that the axial direction of the rotating shaft 1a of the photosensitive member 1 is the Z axis, a load around the Z axis generated when the drive motor 51 is driven is generated in the support member 70 via the drive shaft 51a. At this time, a compressive load and a tensile load are applied to the constricted portions 71a and 71b and the bridge portions 72a and 72b of the support member 70 instead of a load due to torsion. The support member 70 in the present invention has a single plate shape as a member used to absorb the declination, and therefore has high rigidity in the rotation direction of the drive shaft 51a, and rotation control by the compression load and the tensile load. Can be suppressed.

Thus, as described in the above embodiment, the drive motor can cope with the deflection angles in all directions, and the axis of the rotation shaft 1a of the photosensitive member 1 and the drive shaft 51a of the drive motor are on the same axis. 51 can be fixed. Therefore, it is possible to reduce the generation of a load that tends to bend the rotating shaft 1a of the photosensitive member 1 and the driving shaft 51a of the driving motor 51.
In addition, since the support member 70 used to absorb the declination has a single plate shape, the rigidity is high in the rotation direction of the drive shaft 51a, and the rotation control load due to the compression load and the tensile load is suppressed. can do.
Therefore, the rotational speed fluctuations of the rotating body such as the photosensitive member 1 and the driving source such as the driving motor due to the deviation angle between the rotating shaft of the rotating member such as the photosensitive member 1 and the driving shaft of the driving source such as the driving motor 51 or the like. Generation of vibration can be suppressed with an inexpensive and simple structure.

(Aspect D)
In the aspect B or C, the support member such as the support member 70 is the direction of the apex of the angle formed by the axis of the rotating shaft of the rotating body such as the rotating shaft 1a of the photosensitive member 1 and the driving shaft such as the driving shaft 51a. Accordingly, the pair of twisted portions, the first twisted portion, or the second double twisted portion is twisted and deformed, thereby swinging the drive source.
Thereby, the deflection angles in all directions formed by the rotating shaft of the rotating body and the driving shaft of the rotating body driving device can be absorbed.

(Aspect E)
A rotating body such as the photosensitive member 1 and a driving shaft such as a driving shaft 51 a that rotates by receiving a driving force from a driving source such as the driving motor 51, and the rotating body such as the rotating shaft 1 a of the photosensitive member 1 rotates. In an image forming apparatus such as a printer 100 having a rotating body driving device such as the rotating body driving device 50 that rotationally drives the rotating body by connecting and fixing the shaft and the driving shaft, the rotating body driving device is an aspect. One embodiment of A to D was used.
As a result, in the image forming apparatus, fluctuations in rotational speed and vibrations of the rotating body and the rotating body drive device due to the declination between the rotating shaft of the rotating body and the drive shaft of the rotating body drive device can be generated with an inexpensive and simple structure. Can be suppressed.

(Aspect F)
In aspect E, the rotating body is a photoconductor.

(Aspect G)
In aspect E, the rotating body is a secondary transfer body.

DESCRIPTION OF SYMBOLS 1 Photoconductor 1a Rotating shaft 2 of photoconductor Transfer material 10 Process cartridge 20 Primary transfer means 21 Transfer belt 22 Transfer belt drive roller 23 Primary transfer roller 24 Opposed roller 31 Secondary transfer roller 32 Fixing means 50 Rotating body drive device 51 Drive motor 51a Drive shaft 51b Drive shaft hole 52 Motor fixing screw 52a Motor fixing screw screw hole 53 Support member fixing screw 53a Support member fixing screw screw hole 60a End portion 60b End portion 60 Joint 61 Joint 70 Support member 71 Constricted portion 72 Bridge Part 73 Slit 74 First fixing part 75 Relay part 76 Second fixing part 100 Printer 101 Apparatus main body member 101a Bearing 102 Apparatus main body member 102a Mounting surface

Japanese Patent No. 4359102 JP-A-6-313439

Claims (7)

A rotating body drive that includes a rotating body and a driving shaft that rotates by receiving a driving force from a drive source, and the rotating shaft of the rotating body and the driving shaft are coupled and fixed to each other to rotate the rotating body. In the device
The drive source is fixed to the image forming apparatus main body via a support member that is an elastic body, and the support member supports the rotating shaft and the drive shaft. And a rotating body drive device having a torsional portion having a torsional rigidity lower than that of the drive shaft, and wherein the support member is deformable in a torsional direction.   2. The rotating body drive device according to claim 1, wherein the torsional portion includes a plurality of torsional portions, and the support member is configured to have a first fixing portion to which the driving source is fixed and an outer periphery of the first fixing portion. And a second fixing portion that is fixed to the image forming apparatus main body, and the first fixing portion and the second fixing portion are coupled by a pair of twisted portions. A rotating body drive device.   2. The rotating body drive device according to claim 1, wherein the twisted portion is configured by a plurality of twisted portions, the support member has a single plate shape, the first fixed portion to which the drive source is fixed, and the first A relay portion that surrounds the outer periphery of the first fixing portion with a gap; and a second fixing portion that is positioned on the outer periphery of the relay portion and is fixed to the image forming apparatus main body. The first fixing part and the relay part are coupled by a pair of first twist parts, and the second fixing part and the relay part are coupled by a pair of second twist parts, and the first twist part and the first twist part A rotating body drive device, wherein two twisted portions are the plurality of twisted portions.   4. The rotating body drive device according to claim 2, wherein the support member includes the pair of twisted portions and the first twisted portion according to a direction of an apex of an angle formed by an axis of a rotating shaft of the rotating body and an axis of the driving shaft. A rotating body drive device characterized in that the drive source is swung by twisting and deforming one twisted part or the second double twisted part.   A rotating body drive that includes a rotating body and a driving shaft that rotates by receiving a driving force from a drive source, and the rotating shaft of the rotating body and the driving shaft are coupled and fixed to each other to rotate the rotating body. An image forming apparatus having the apparatus, wherein the rotating body driving device according to any one of claims 1 to 4 is used as the rotating body driving device.   6. The image forming apparatus according to claim 5, wherein the rotating body is a photoconductor.   6. The image forming apparatus according to claim 5, wherein the rotating body is a secondary transfer body.

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