JP6642066B2 - Support member, image carrier, image forming apparatus - Google Patents

Description

  The present invention relates to a support member, an image carrier, and an image forming apparatus.

  A sliding member that slidably contacts the inner wall surface of the photosensitive drum and presses the inner wall surface with a predetermined force is disposed inside the photosensitive drum in the image forming apparatus described in Patent Document 1.

JP 08-54804 A

  In this way, by arranging the sliding contact member inside the photoconductor drum, vibration of the photoconductor drum caused when the photoconductor drum is charged by a voltage obtained by superimposing an AC voltage on a DC voltage is to be suppressed.

  The sliding contact member (supporting member) described in Patent Literature 1 has a separation portion that is partially separated in the circumferential direction and a single groove that faces the separation portion in the axial direction of the photosensitive drum (cylinder). It is formed to extend. The sliding member has a C-shaped cross section in which both ends are opposed to each other.

  Here, in a state in which the sliding contact member is supported inside the photosensitive drum, the distance between one end and the other end tends to increase. Therefore, the photoconductor drum may be deformed.

  An object of the present invention is to suppress deformation of a cylindrical body as compared with a case where a C-shaped support member having only one groove is used.

The support member according to the first aspect is supported inside a cylinder constituting the image holding member, and is formed in an arc shape in which a part extending in an axial direction of the cylinder is formed in a part in a circumferential direction. A first groove portion formed on the opposite side of the separation portion with respect to the center of the cylindrical body and extending in the axial direction when viewed from the axial direction while being supported inside the body; A pair of second grooves extending in the axial direction, having a symmetry with respect to a straight line passing through the spaced portion and the center of the cylindrical body, when viewed from the axial direction. It is characterized by the following.

The support member according to a second aspect is the support member according to the first aspect , wherein the first groove portion is formed on an outer peripheral side, and the pair of second groove portions is formed on an inner peripheral side. And

The support member according to a third aspect is the support member according to the second aspect , wherein a gate mark is formed on a portion of an outer surface located radially outside the second groove, and the second groove and the second groove are formed. The portion where the gate mark is located at the bottom of the groove formed between the outer surface and the outer surface is thicker than other portions.

The support member according to a fourth aspect is the support member according to the third aspect , wherein the thick part provided at the bottom of one of the second grooves and the thick part provided at the bottom of the other second groove. Are shifted in the longitudinal direction of the second groove.

The image holding body according to a fifth aspect is a cylindrical body that holds an image on a surface in a cylindrical shape, and the support member according to any one of the first to fourth aspects supported inside the cylindrical body. , Is provided.

An image forming apparatus according to a sixth aspect provides the image holding body according to the fifth aspect , a charging device that charges the image holding body, and an exposure that forms an electrostatic latent image by exposing the charged image holding body. And a developing device for developing the electrostatic latent image formed on the surface of the image holding member as a toner image, and a transfer device for transferring the toner image to a recording medium.

According to the support member of the first aspect, the deformation of the cylindrical body can be suppressed as compared with the case where a support member having a C-shaped cross section in which only one groove is formed is used.

According to the support member of the second aspect, the deformation of the cylindrical body can be suppressed as compared with the case where all the grooves are formed on the same surface.

According to the support member of the third aspect , at the time of molding, compared with the case where the resin flows in from the thin portion at the bottom of the groove, the flowability of the resin flowing from the portion of the gate mark of the thick portion is increased. Can be.

According to the support member of the fourth aspect , the silencing effect can be enhanced as compared with the case where the thick portion is provided at the central portion in the length direction of the second groove portion.

According to the image carrier of the fifth aspect , the density unevenness of the image formed on the image carrier is reduced as compared with the case where the support member according to any one of the first to fourth aspects is not provided. Can be suppressed.

According to the image forming apparatus of the sixth aspect , the density unevenness of the output image can be suppressed as compared with the case where the image holding member according to the fifth aspect is not provided.

(A) (B) It is sectional drawing which showed the support member which concerns on 1st Embodiment of this invention. It is the figure which showed the deformation mode of the cylinder when the support member which concerns on 1st Embodiment of this invention is supported by the cylinder. FIG. 2 is a perspective view illustrating a support member according to the first embodiment of the present invention. (A) (B) It is an expanded sectional view showing each slot in a support member concerning a 1st embodiment of the present invention. FIG. 2 is a cross-sectional view illustrating the image carrier according to the first embodiment of the present invention. FIG. 2 is a schematic configuration diagram illustrating an image forming unit of the image forming apparatus according to the first embodiment of the present invention. FIG. 1 is a schematic configuration diagram illustrating an image forming apparatus according to a first embodiment of the present invention. (A) (B) It is sectional drawing which showed the support member which concerns on the comparative example with respect to the support member which concerns on 1st Embodiment of this invention. It is a drawing showing a deformation mode of a cylinder when a support member according to a comparative example is supported by a cylinder with respect to the support member according to the first embodiment of the present invention. (A) (B) It is sectional drawing which showed the support member which concerns on 2nd Embodiment of this invention. It is the figure which showed the deformation mode of the cylinder when the support member which concerns on 2nd Embodiment of this invention is supported by the cylinder. (A) (B) It is sectional drawing which showed the support member which concerns on 3rd Embodiment of this invention. It is the figure which showed the deformation mode of the cylinder when the support member which concerns on 3rd Embodiment of this invention was supported by the cylinder. (A) (B) It is sectional drawing which showed the support member which concerns on 4th Embodiment of this invention. It is the figure which showed the deformation mode of the cylinder when the support member which concerns on 4th Embodiment of this invention is supported by the cylinder. It is a perspective view showing the support member concerning a 5th embodiment of the present invention. (A) is a front view of the support member according to the fifth embodiment of the present invention, and (B) is a cross-sectional view along the line AA of (A). (A) (B) It is sectional drawing which showed the metal mold | die structure used for shape | molding the support member which concerns on 5th Embodiment of this invention. It is a figure which shows the support member which concerns on 6th Embodiment of this invention, (A) is a front view, (B) is sectional drawing which followed the BB line of (A). It is a top view showing operation of a support member concerning a 6th embodiment of the present invention. It is a figure showing the relation between noise peak frequency and noise grade value of a 6th embodiment of the present invention, and a comparative example.

<First embodiment>
An example of a support member, an image carrier, and an image forming apparatus according to a first embodiment of the present invention will be described with reference to FIGS. The arrow H shown in the figure indicates the apparatus vertical direction (vertical direction), the arrow W indicates the apparatus width direction (horizontal direction), and the arrow D indicates the apparatus depth direction (horizontal direction).

(overall structure)
As shown in FIG. 7, the image forming apparatus 10 according to the present embodiment includes a storage unit 14 that stores a sheet member P as a recording medium from below in a vertical direction (direction of an arrow H) and upward. A transport unit 16 that transports the sheet member P stored in the storage unit 14, an image forming unit 20 that forms an image on the sheet member P transported from the storage unit 14 by the transport unit 16, and a document that reads the read document G The reading unit 22 is provided in this order.

(Container)
The accommodating portion 14 is provided with an accommodating member 26 that can be pulled out from the apparatus main body 10A of the image forming apparatus 10 to the near side in the apparatus depth direction, and the sheet member P is stacked on the accommodating member 26. Further, the storage unit 14 is provided with a delivery roll 32 that sends out the stacked sheet members P to a transport path 28 that configures the transport unit 16.

(Transport section)
The transport unit 16 is disposed on the downstream side in the transport direction of the sheet member P with respect to the delivery roll 32 (hereinafter, referred to as “the downstream side in the transport direction”), and separates and transports the sheet members P one by one. A roll 34 is provided.

  In the transport path 28, on the downstream side in the transport direction with respect to the separation roll 34, a positioning roller 36 that stops the sheet member P once and sends the sheet member P to a transfer position T described later at a predetermined timing. Are located.

  Further, a discharge roll 76 that discharges the sheet member P on which an image has been formed by the image forming unit 20 to a discharge unit 74 formed above the image forming unit 20 is disposed at the end side of the transport path 28. .

(Document scanning section)
The document reading unit 22 is provided with a light source 44 that irradiates light to the read document G conveyed by the automatic document feeder 40 that conveys the read document G, or to the read document G placed on the platen glass 42. .

(Image forming unit)
As shown in FIG. 6, the image forming unit 20 includes an image holding member 56 and a charging roll 58 as an example of a charging device for charging the surface of the image holding member 56. The image forming unit 20 also includes an exposure device 60 (see FIG. 7) that exposes the charged image carrier 56 based on the image data to form an electrostatic latent image, and develops the electrostatic latent image to form a toner. A developing device 62 for visualizing the image.

  Further, the image forming unit 20 includes a transfer roll 64 that transfers the toner image formed on the surface of the image holding member 56 to the sheet member P conveyed along the conveyance path 28. The image forming unit 20 includes a heating roller 66H and a pressure roller 66N, and includes a fixing device 66 (see FIG. 7) that heats and presses the toner image on the sheet member P to fix the toner image on the sheet member P. ing. Further, the image forming unit 20 includes a cleaning blade 68 that scrapes off the toner remaining on the image carrier 56 after the transfer of the toner image from the image carrier 56 to clean the image carrier 56.

  The details of the image carrier 56 and the charging roll 58 will be described later.

(Operation of the overall configuration)
In the image forming apparatus 10, an image is formed as follows.
First, the charging roll 58 to which the voltage is applied comes into contact with the surface of the image carrier 56 to uniformly negatively charge the surface of the image carrier 56 at a predetermined potential. Subsequently, the exposure device 60 irradiates exposure light onto the charged surface of the image carrier 56 based on the image data read by the document reading unit 22 or data input from the outside to form an electrostatic latent image.

  As a result, an electrostatic latent image corresponding to the image data is formed on the surface of the image carrier 56. Further, this electrostatic latent image is developed by the developing device 62 and is visualized as a toner image.

  Then, the sheet member P sent from the storage member 26 to the transport path 28 by the sending roll 32 is sent to the transfer position T at a timing determined by the positioning roll 36. At the transfer position T, the toner image formed on the surface of the image holding member 56 is transferred to the sheet member P by nipping and conveying the sheet member P between the image holding member 56 and the transfer roll 64.

  The toner image transferred to the sheet member P is fixed to the sheet member P when the sheet member P passes between the heating roll 66H and the pressure roll 66N. Then, the sheet member P having the toner image fixed on its surface is discharged to a discharge unit 74 by a discharge roll 76.

(Main configuration)
Next, the image carrier 56 and the charging roll 58 will be described.
(Charging roll)
As shown in FIG. 5, the charging roll 58 extends in the depth direction of the apparatus, and has a shaft portion 58A formed of a metal material (for example, stainless steel), and a cylindrical rubber material into which the shaft portion 58A is inserted. And a roll portion 58B formed by the above.

  Further, both end portions of the shaft portion 58A are exposed to the outside from the roll portion 58B, and are rotatably supported by the pair of bearing members 102. A biasing member 104 for biasing each bearing member 102 toward the image holding member 56 is disposed on the opposite side of the image holding member 56 with the shaft portion 58A interposed therebetween. With this configuration, when the roll portion 58B of the charging roll 58 is pressed against the image holding member 56 and the image holding member 56 rotates, the charging roll 58 rotates following the rotation.

  A superimposed voltage obtained by superimposing an AC voltage on a DC voltage is applied from the power supply 106 to the shaft portion 58A.

(Image carrier)
As shown in FIG. 5, the image holding body 56 has a cylindrical tube 108 extending in the device depth direction, and a device depth direction in the tube 108 (a direction similar to the axial direction of the tube 108 in the present embodiment). And a transmission member 110 fixed to one end (upper side in the figure) of the transmission member 110. Further, the image holding body 56 includes a support member 112 fixed to the other end side (the lower side in the drawing) of the cylinder 108 in the apparatus depth direction. Further, the image holding member 56 includes a support member 116 which is disposed inside the cylinder 108 and suppresses a cross section of the cylinder 108 from being periodically deformed. The details of the support member 116 will be described later.

  The cylinder 108 is obtained by applying a photosensitive layer to an outer surface of a base material formed of a metal material in a cylindrical shape. In the present embodiment, the base of the cylinder 108 is an aluminum tube, and the thickness of the cylinder 108 is 0.8 [mm]. The outer diameter of the cylinder 108 is 30 [mm], and the length of the cylinder 108 in the device depth direction is 340 [mm].

  The transmission member 110 is formed in a disk shape with a resin material, and is fixed to one end of the cylinder 108 by partially fitting the inside of the cylinder 108, and closes one end of the opened cylinder 108. I have. Further, the transmission member 110 is formed with a cylindrical through hole 110A passing through the center F of the cylindrical body 108. A plurality of recesses 110B are formed on the outer surface of the transmission member 110 facing outward in the apparatus depth direction so as to sandwich the through hole 110A.

  The support member 112 is formed in a disc shape from a resin material, and is fixed to the other end of the cylinder 108 by partially fitting the inside of the cylinder 108, and closes the other end of the opened cylinder 108. are doing. Further, the support member 112 is formed with a cylindrical through hole 112A passing through the center F of the cylindrical body 108.

[Others]
As shown in FIG. 5, a motor 80 that generates a rotational force transmitted to the image holding member 56 (the transmission member 110) is disposed at one end of the image holding member 56 in the apparatus depth direction.

  The motor 80 is mounted on a plate-like frame 84. Further, the motor shaft portion 80A of the motor 80 is inserted into the through hole 110A of the transmission member 110. A plate-shaped bracket 88 having a bent tip inserted into the recess 110B of the transmission member 110 is fixed to the outer peripheral surface of the motor shaft 80A. Thus, the transmission member 110 transmits the rotational force generated by the motor 80 to the cylinder 108.

  On the other hand, a stepped cylindrical shaft member 90 that rotatably supports the image holding member 56 (support member 112) is disposed on the other end side of the image holding member 56 in the apparatus depth direction. The shaft member 90 is attached to a plate-like frame member 92.

  The shaft member 90 has a shaft portion 90C that extends above the center F of the cylindrical body 108 and is inserted into the through hole 112A of the support member 112. A gap is provided between the inner peripheral surface of the through hole 112A and the outer peripheral surface of the shaft portion 90C, and the support member 112 functions as a so-called sliding bearing with respect to the shaft portion 90C.

  In this configuration, when the motor 80 is operated, the motor shaft 80A rotates. The rotation of the motor shaft 80A is transmitted to the cylinder 108 via the bracket 88 and a transmission member 110 fixed to one end of the cylinder 108. Then, the support member 112 fixed to the other end side of the cylindrical body 108 rotates with respect to the shaft portion 90C, so that the image holding body 56 rotates around the center F.

(Support member)
Next, the support member 116 supported inside the cylinder 108 will be described.
As shown in FIG. 5, the support member 116 is fitted into the inside of the cylinder 108 and is supported at the center of the cylinder 108 in the apparatus depth direction. Then, as shown in FIG. 1 (B), the arc-shaped outer peripheral surface 118 of the support member 116 contacts the inner surface 108A of the cylinder 108 and presses the inner surface 108A, so that the support member 116 becomes cylindrical. 108.

  Specifically, the support member 116 is formed using a resin material. The support member 116 has a separation portion 116A formed in a part in the circumferential direction in the apparatus depth direction (the axial direction of the cylindrical body 108), and has a circular arc shape with both ends facing each other when viewed from the apparatus depth direction. I have. The support member 116 extends in the apparatus depth direction, as shown in FIG. In the present embodiment, the support member 116 is formed using ABS resin (acrylonitrile butadiene styrene). The thickness of the support member 116 is 4 [mm], and the length of the support member 116 in the apparatus depth direction is 100 [mm].

  Further, a portion of the support member 116 opposite to the separated portion 116A with respect to the center F of the cylinder 108 is shown in FIG. 1B with the support member 116 being supported inside the cylinder 108. Thus, the groove 116B as an example of the first groove is formed when viewed from the apparatus depth direction. The groove 116B is formed on the outer peripheral surface 118 of the support member 116, and extends in the apparatus depth direction. In the present embodiment, the groove width of the groove 116B is 2 [mm] and the thickness of the groove is 1 [mm], that is, the depth of the groove 116B of the present embodiment is 3 [mm].

  In addition, the support member 116, in a state where the support member 116 is supported inside the cylindrical body 108, is symmetrical with respect to a straight line E1 passing through the center and the center F of the separated portion 116A when viewed from the apparatus depth direction. A pair of groove portions 116G is formed as an example of the pair of second groove portions. Note that the center of the separation portion 116A is the middle of the space formed between the one end portion 116C and the other end portion 116D of the support member 116 constituting the separation portion 116A.

  Each groove 116G is formed on the inner peripheral surface 120 of the support member 116, and extends in the apparatus depth direction. Further, each of the grooves 116G is formed in the circumferential direction at an intermediate position between the separation part 116A and the groove 116B. Further, in a state where the support member 116 is supported inside the cylindrical body 108, when viewed from the apparatus depth direction, the angle formed between the straight line E3 passing through the center in the circumferential direction of the pair of groove portions 116G and the above-described straight line E1 is: 90 degrees. The straight line E3 and the straight line E1 intersect at the center F. In the present embodiment, the groove width of the groove portion 116G is 2 [mm], and the groove depth is 3 [mm].

  The outer diameter of the support member 116 in a free state where the support member 116 is not supported inside the cylinder 108 is larger than the inner diameter of the cylinder 108 by 0.2 [mm] (FIG. 1). (A)).

  In this configuration, when supporting the support member 116 inside the cylindrical body 108, first, the support member 116 is gripped by a chuck (not shown). When the support member 116 is grasped, the groove 116B and the pair of grooves 116G of the support member 116 are deformed so that the separation distance K1 of the separation part 116A is shortened (FIGS. 1A and 1B). )reference). Then, the support member 116 is bent, and in this bent state, the support member 116 is inserted into the cylindrical body 108.

  Here, the deformation of the groove 116B causes the support member 116 to bend in the device width direction (left-right direction in the figure), and the pair of grooves 116G deforms, thereby causing the support member 116 to move in the device vertical direction (vertical direction in the figure). To bend.

  4B, the vicinity of the groove 116B of the support member 116 in a free state is indicated by a two-dot chain line, and the vicinity of the groove 116B of the support member 116 supported inside the cylinder 108 is indicated by a solid line. It is shown.

  As shown in FIG. 4B, in a state where the support member 116 is supported inside the cylindrical body 108, the open side of the groove 116B becomes narrow, so that the groove 116B is deformed. By deforming the groove 116B in this manner, the outer peripheral surface 118 near the groove 116B is considered to be depressed as compared with the free state.

  Further, in FIG. 4A, the vicinity of the groove 116G of the support member 116 in the free state is indicated by a two-dot chain line, and the vicinity of the groove 116G of the support member 116 supported inside the cylinder 108 is indicated by a solid line. It is shown.

  As shown in FIG. 4A, in a state where the support member 116 is supported inside the cylindrical body 108, the open side of the groove 116G is narrowed, so that the groove 116G is deformed. By deforming the groove 116G in this manner, the outer peripheral surface 118 near the groove 116G is considered to protrude as compared with the free state.

(Operation of the main part configuration)
Next, the operation of the main part configuration will be described.
When the surface of the image carrier 56 is charged, a superimposed voltage obtained by superimposing an AC voltage (1 kHz to 3 kHz) on a DC voltage is applied from the power supply 106 to the shaft portion 58A of the charging roll 58 (see FIG. 5). An alternating electric field is generated between the charging roll 58 and the image carrier 56 by the AC voltage forming the superimposed voltage. Accordingly, a periodic (2 kHz to 6 kHz) electrostatic attraction force is generated between the image holding member 56 and the charging roll 58. This electrostatic attraction force becomes a vibrating force on the cylinder 108. However, a support member 116 whose outer peripheral surface 118 is in contact with the inner surface 108 </ b> A of the cylindrical body 108 is supported inside the cylindrical body 108. For this reason, even if the cross section of the cylindrical body 108 changes periodically and the cylindrical body 108 tries to vibrate, the vibration of the cylindrical body 108 is suppressed.

  Next, a description will be given of an evaluation result obtained by evaluating the deformation of the cross section of the cylindrical body 108 by the finite element method simulation using the support member 116 according to the first embodiment and the support member 200 according to the comparative example.

  First, the configuration of the support member 200 according to the comparative embodiment will be described below. Note that the description of the support member 200 will be mainly given of portions different from the support member 116.

  In a state where the support member 200 is not supported inside the cylindrical body 108 (free state), the support member 200 is located between the center of the separated portion 200A and the center of the separation portion 200A when viewed from the apparatus depth direction, as shown in FIG. It is formed symmetrically with respect to a straight line E4 passing through the center of the groove 200B. Specifically, the support member 200 is formed by connecting a circular arc-shaped portion 202 on the right side in the drawing and a circular arc-shaped portion 204 on the left side in the drawing by a groove 200B.

  Further, the support member 200 is not provided with a pair of grooves that are symmetric with respect to the straight line E4. Thus, the support member 200 has a C-shaped cross section.

  In this configuration, when supporting the support member 200 inside the cylindrical body 108, first, the support member 200 is gripped. When the support member 200 is gripped, the groove 200B is deformed so that the separation distance K1 of the separation part 200A is shortened (see FIGS. 8A and 8B). Then, the support member 200 is bent, and in this bent state, the support member 200 is inserted into the cylindrical body 108.

  FIG. 9 shows a result of a simulation using the support member 200 according to the comparative embodiment, and FIG. 2 shows a result of a simulation using the support member 116 according to the first embodiment. I have. The broken line shown in each figure shows the shape of the cylindrical body 108 that does not support the support members 116 and 200, and the solid line shown in each figure shows the shape of the cylindrical body 108 that supports the support members 116 and 200. I have. Note that the degree of deformation of the cylinder 108 is exaggerated so that the deformation of the cylinder 108 can be easily understood.

  As shown in FIG. 9, the cylindrical body 108 supporting the support member 200 according to the comparative embodiment is deformed so as to greatly expand in the width direction of the apparatus (the left-right direction in the figure). This is probably because the support member 200 is deformed in the support member 200 so as to bend in the device width direction (the left-right direction in the drawing) due to the deformation of the groove 200B. Further, it is considered that a groove for bending the support member 200 in the vertical direction of the apparatus is not formed in the support member 200.

  On the other hand, in the cylindrical body 108 supporting the support member 116 according to the first embodiment, as shown in FIG. 2, as compared with the cylindrical body 108 supporting the support member 200 in which only one groove is formed (see FIG. 2). 9), the deformation of the cylinder 108 in the apparatus width direction and the apparatus vertical direction (vertical direction in the figure) is suppressed. This is probably because the support member 116 according to the first embodiment has a pair of grooves 116G for bending the support member 116 in the vertical direction of the apparatus.

(Summary)
As described above, in the support member 116 of the first embodiment, the pair of grooves 116G for bending the support member 116 in the vertical direction of the device is formed. In comparison, deformation of the cylinder 108 is suppressed.

  Further, with respect to the image carrier 56, the deformation of the cylinder 108 is suppressed, so that the density unevenness of the toner image formed on the image carrier 56 is suppressed.

  Further, in the image forming apparatus 10, the density unevenness of the output image is suppressed by suppressing the density unevenness of the toner image on the image holding member 56.

<Second embodiment>
Next, an example of a support member, an image carrier, and an image forming apparatus according to a second embodiment of the present invention will be described with reference to FIGS. The same members and the like as those in the first embodiment are denoted by the same reference numerals, and the description thereof will be omitted, and portions different from the first embodiment will be mainly described.

  In a state where the support member 156 of the second embodiment is supported inside the cylinder 108, as shown in FIG. 10B, the support member 156 has a center of the cylinder 108 when viewed from the apparatus depth direction. A groove 156B as an example of a first groove is formed on the opposite side of the separating portion 116A across F. The groove 156B is formed on the inner peripheral surface 160 of the support member 156, and extends in the device depth direction.

  FIG. 11 shows a result of a simulation when the support member 156 according to the second embodiment is used.

  The support member 156 according to the second embodiment has a groove 116G for bending the support member 156 in the vertical direction of the device. For this reason, as shown in FIG. 11, the deformation of the cylinder 108 in the device width direction and the device vertical direction (vertical direction in the figure) is suppressed as compared with the support member 200 according to the comparative embodiment (see FIG. 9). ing. It is considered that the reason why the deformation mode is different from the case where the support member 116 according to the first embodiment is used is that the groove 156B is formed on the inner peripheral surface 160. Other operations are the same as those of the first embodiment.

<Third embodiment>
Next, an example of a support member, an image carrier, and an image forming apparatus according to a third embodiment of the present invention will be described with reference to FIGS. The same members and the like as those in the first embodiment are denoted by the same reference numerals, and the description thereof will be omitted, and portions different from the first embodiment will be mainly described.

  As shown in FIG. 12B, the outer peripheral surface 168 of the support member 166 of the third embodiment has a pair of second groove portions so as to be symmetric with respect to the straight line E1 when viewed from the device depth direction. A pair of grooves 166G is formed as an example.

  FIG. 13 shows a result of a simulation when the support member 166 according to the third embodiment is used.

  A groove 166G for bending the support member 166 in the vertical direction of the device is formed in the support member 166 according to the third embodiment. For this reason, as shown in FIG. 13, the deformation of the cylinder 108 in the apparatus width direction and the apparatus vertical direction (vertical direction in the figure) is suppressed as compared with the support member 200 according to the comparative embodiment (see FIG. 9). ing. It is considered that the reason why the deformation mode is different from the case where the support member 116 according to the first embodiment is used is that the groove 166G is formed on the outer peripheral surface 168. Other operations are the same as those of the first embodiment.

<Fourth embodiment>
Next, an example of a support member, an image carrier, and an image forming apparatus according to a fourth embodiment of the present invention will be described with reference to FIGS. The same members and the like as those in the first embodiment are denoted by the same reference numerals, and the description thereof will be omitted, and portions different from the first embodiment will be mainly described.

  In a state where the support member 176 of the fourth embodiment is supported inside the cylindrical body 108, as shown in FIG. 14B, the support member 176 has the center of the cylindrical body 108 as viewed from the apparatus depth direction. A groove 176B as an example of a first groove is formed on the opposite side of the separating portion 116A with respect to F. The groove 176B is formed on the inner peripheral surface 180 of the support member 176, and extends in the device depth direction.

  Further, a pair of groove portions 176G as an example of a pair of second groove portions are formed on the outer peripheral surface 178 of the support member 176 so as to be symmetric with respect to the straight line E1 when viewed from the apparatus depth direction.

  FIG. 15 shows a result of a simulation when the support member 176 according to the fourth embodiment is used.

  The support member 176 according to the fourth embodiment has a groove 176G for bending the support member 176 in the vertical direction of the device. For this reason, as shown in FIG. 15, the deformation of the cylindrical body 108 in the apparatus width direction and the apparatus vertical direction (vertical direction in the figure) is suppressed as compared with the support member 200 according to the comparative embodiment (see FIG. 9). ing. The reason why the deformation mode is different from the case where the support member 116 according to the first embodiment is used is that the groove 176B is formed on the inner peripheral surface 180 and the groove 176G is formed on the outer peripheral surface 178. it is conceivable that. Other operations are the same as those of the first embodiment.

  Here, simulation results for the support members 116, 156, 166, and 176 of each embodiment will be compared. Then, when the support member 116 according to the first embodiment is used, as compared with the case where the support members 156, 166, and 176 according to the other embodiments are used, the apparatus width direction and the apparatus vertical direction (up and down in the drawing) (Direction), the deformation of the cylinder 108 is suppressed.

  This is because, by using the support member 116, the groove 116 </ b> B formed on the outer peripheral surface 118 of the support member 116 and the pair of grooves 116 </ b> G formed on the inner peripheral surface 120 correspond to the support member 156 according to another embodiment. This is probably because the grooves 166 and 176 are deformed to a similar degree.

  Although the present invention has been described in detail with respect to a specific embodiment, the present invention is not limited to this embodiment, and various other embodiments can be taken within the scope of the present invention. That will be apparent to those skilled in the art. For example, in the above-described embodiment, the angle formed by the line (line E3) connecting the center of the one of the grooves 116G, 166G, and 176G with the center F and the line E1 is 90 degrees when viewed from the device depth direction. However, the support members 116, 156, 166, and 176 may be bent in the vertical direction of the apparatus, and may be other than 90 degrees. In particular, if the above-described angle is 60 degrees or more and 120 degrees or less, the support members 116, 156, 166, and 176 are effectively bent in the vertical direction of the device.

  Further, in the above embodiment, when viewed from the apparatus depth direction, the groove portions 116G, 166G, and 176G are symmetrical with respect to the straight line E1, but any symmetry (a positional relationship in which the portions face each other) is sufficient. .

  Further, in the above embodiment, the support members 116, 156, 166, and 176 are circular in the free state, but need not be circular.

  Further, in the above embodiment, the groove portion is constituted by the pair of side surfaces and the bottom surface, but may be V-shaped or U-shaped.

  Further, in the above embodiment, a pair of grooves is formed in the support member with the straight line E1 as a line of symmetry, but another groove may be formed with the line E1 as a line of symmetry.

  Although not particularly described in the first embodiment, the thickness of the groove 116G may be smaller than the thickness of the groove 116B. That is, the depth of the groove 116G may be greater than the depth of the groove 116B. Thereby, the deformation of the cylindrical body is suppressed.

<Fifth embodiment>
Next, an example of the support member 300 according to the fifth embodiment of the present invention will be described with reference to FIGS. The description of the same members and the like as in the first embodiment will be omitted, and portions different from the first embodiment will be mainly described.

  As shown in FIG. 16, the outer peripheral surface 302 of the support member 300 according to the fifth embodiment is provided with a band-shaped step portion 304 extending in the longitudinal direction N (the depth direction of the device) of the support member 300. At the center in the width direction of the step portion 304, a separation portion 300A extending in the longitudinal direction N (device depth direction) is formed over the entire length, and the support member 300 is disposed in the longitudinal direction N (device depth direction). When viewed from above, both ends are in an arc shape facing each other.

  An outer groove portion 300B as an example of a first groove portion is formed in the support member 300 at a portion opposite to the separated portion 300A with respect to the center axis C of the support member 300. The outer groove portion 300B is formed on the outer peripheral surface 302 constituting the outer surface of the support member 300, and extends in the longitudinal direction N (the depth direction of the device).

  Further, in the support member 300, a first inner groove portion 300C and a second inner groove portion 300D as an example of a pair of second groove portions are formed symmetrically with respect to a straight line E6 passing through the center of the separation portion 300A and the central axis C. Have been. Note that the center of the separated portion 300A is an intermediate portion in a space formed between one end and the other end of the support member 300 constituting the separated portion 300A.

  Each of the inner grooves 300C and 300D is formed on the inner peripheral surface 306 of the support member 300 and extends in the longitudinal direction N (the depth direction of the apparatus). It is formed in the middle of the groove 300B. When the support member 300 is viewed from the longitudinal direction N (the depth direction of the apparatus), the angle formed by the straight line E7 passing through the center in the circumferential direction of the pair of inner grooves 300C and 300D and the straight line E6 is 90 degrees. The straight line E6 and the straight line E7 intersect at the center axis C.

  A first groove bottom 310 and a second groove bottom 312 are formed between the first inner groove 300C and the second inner groove 300D and the outer peripheral surface 302, as shown in FIG. 310 and 312 are formed thinner than the general portion 300F of the support member 300.

  Further, on the outer peripheral surface 302 of the support member 300, a first flat surface 302A and a second flat surface 302B are formed over the entire area in the longitudinal direction N at a portion intersecting the straight line E7 described above. 302B is formed so as to be orthogonal to the straight line E7. Gate traces 314A and 314B are formed on each of the flat surfaces 302A and 302B. The gate traces 314A and 314B are portions located radially outward from the respective inner groove portions 300C and 300D. It is provided at the center in the longitudinal direction N (the apparatus depth direction).

  That is, the support member 300 is formed by resin molding using a mold as shown in FIG. The support member 300 forms a hollow portion and slides to both sides in the longitudinal direction, a core 320 that forms the outer groove portion 300B side from the above-described straight line E6, and forms a separated portion 300A side from the straight line E6. And a cavity mold 324 that is formed. Between the core mold 322 and the cavity mold 324, gate portions 326A and 326B into which resin is injected are set, and the support member 300 is formed by the resin injected from the gate portions 326A and 326B provided on both sides. Is done. The gate portions 326A and 326B are set on the flat surfaces 302A and 302B described above, and the gate marks 314A and 314B described above remain on the flat surfaces 302A and 302B (see FIGS. 16 and 17).

  As shown in FIG. 17, in the groove bottoms 310 and 312 located inside the gate traces 314A and 314B, a portion where the gate traces 314A and 314B are located is formed thicker inward than other portions. . Accordingly, the first thick portion 310A and the second thick portion 312A are provided at the positions of the first groove bottom 310 and the second groove bottom 312 where the gate traces 314A and 314B are located.

  In the support member 300 according to the fifth embodiment, the space between the core mold 322 and the core 320 and the space between the cavity mold 324 and the core 320, which form the groove bottoms 310 and 312 at the time of molding, are the thick portions 310A and 312A. Is set to be wider than other portions. Gate portions 326A and 326B of a mold are set at portions of the gate traces 314A and 314B on the radially outer side of the thick portions 310A and 312A.

  For this reason, the resin flowing from the gate portions 326A and 326B is diffused after flowing into a large space forming the thick portions 310A and 312A. Thereby, the fluidity of the injected resin can be increased as compared with a case where the resin is directly injected into a narrow space where the thin groove bottom portions 310 and 312 are formed. In addition, by setting the gate portions 326A and 326B at the groove bottom portions 310 and 312, formation of a weld line at the groove bottom portions 310 and 312 can be prevented. Other operations are the same as those of the first embodiment.

<Sixth embodiment>
FIGS. 19 and 20 are views showing a support member 300 according to the sixth embodiment of the present invention. Since the sixth embodiment is a modification of the fifth embodiment, the same members and the like as those of the fifth embodiment are denoted by the same reference numerals and the description thereof will be omitted, and portions different from the fifth embodiment will be mainly described. explain.

  That is, as shown in FIG. 19, gate traces 314A and 314B are formed in the central portion in the longitudinal direction N on each of the flat surfaces 302A and 302B of the support member 300. 9 shows traces of the gate portions 326A and 326B of the mold described in the embodiment (see FIG. 8). As shown in FIG. 19B, the groove bottoms 310 and 312 located inside the gate traces 314A and 314B are formed such that the portions where the gate traces 314A and 314B are located are thicker than other portions. Thick portions 310A and 312A are provided at the portions of the groove bottoms 310 and 312 where the gate traces 314A and 314B are located.

  The first thick portion 310 </ b> A formed in the first groove bottom 310 has a longitudinal N center position of the first thick portion 310 </ b> A from the longitudinal N center position of the first groove bottom 310 to one end side of the support member 300. It is provided staggered. Further, the second thick portion 312A formed on the second groove bottom 312 is such that the center position in the longitudinal direction N of the second thick portion 312A is different from the center position in the longitudinal direction N of the second groove bottom 312 in the other direction. It is provided shifted to the end side. Thereby, both thick portions 310A and 312A are arranged at positions shifted in different directions.

  In the first groove bottom 310, the length of the first one-side component 310B that forms one end of the first thick portion 310A is the first other-end configuration that forms the other end of the first thick portion 310A. The length is set shorter than the length of the portion 310C. The length of the second end portion 312B constituting one end of the second groove bottom 312 from the second thick portion 312A is the second end forming the other end of the second thick portion 312A. The length is set longer than the length of the side component 312C.

  In the sixth embodiment, when the support member 300 is deformed in the radial direction due to the vibration from the cylindrical body, the groove bottoms 310 and 312 are formed on both sides of the high rigidity thick parts 310A and 312A. 310B, 310C, 312B, 312C are displaced in the radial direction.

At this time, in the first groove bottom 310, the first one-side component 310B at one end from the first thick portion 310A is set shorter than the first other-side component 310C at the other end. Therefore, as shown in FIG. 19, the radial displacement H1 of the first end-side component 310B is smaller than the radial displacement H2 of the first other-end component 310C, and the first groove bottom is formed. The entire 310 is tilted. As a result, in the region on the side of the separated portion 300A from the first inner groove portion 300C, as shown in FIG. 20, a part of the force generated in the radial direction is converted into displacement in the longitudinal direction N of the support member 300, and And friction between the outer peripheral surface 302 and the outer peripheral surface 302 to absorb vibration energy.
Thereby, the silencing effect can be enhanced as compared with the case where the region on the side of the separated portion 300A from the first inner groove portion 300C is displaced only in the radial direction.

Further, in the second groove bottom 312, as shown in FIG. 19, the length dimension of the second one end component 312B on one end side from the second thick portion 312A is changed to the second other end configuration on the other end side. It is set longer than the section 312C. For this reason, the radial displacement H3 of the second end component 312B is greater than the radial displacement H4 of the second end component 312C, and the second groove bottom 312 is inclined as a whole. As a result, in the region closer to the separated portion 300A than the second inner groove portion 300D, a part of the force generated in the radial direction is converted into displacement in the longitudinal direction N of the support member 300, as shown in FIG. And friction between the outer peripheral surface 302 and the outer peripheral surface 302 to absorb vibration energy.
Thereby, the silencing effect can be enhanced as compared with the case where the region on the side of the separated portion 300A from the second inner groove portion 300D is displaced only in the radial direction. Other operations are the same as those of the first and fifth embodiments.

  FIG. 21 shows the sixth embodiment (embodiment) having the above-described configuration, and the first and second thick portions 310A and 312A provided at the center position in the longitudinal direction N of the first and second groove bottom portions 310 and 312. It is a figure showing the test result with the comparative example given, and shows the result of having set up support member 300 of an embodiment and support member of a comparative example to a plurality of models A to E, and comparing noise.

  The noise test is performed on the frequency at which the noise peaks, and the noise grade value when the noise is a predetermined allowable value is G3. The noise grade value is degraded as G4 and G5 increase, and is improved as G2 and G1 decrease.

  From this test result, when the support member 300 of the embodiment was used, the noise grade value was “G3” in the model A, which was the same as that of the comparative example. You can see that it has improved.

10 Image Forming Apparatus 56 Image Carrier 58 Charging Roll (Example of Charging Apparatus)
60 Exposure device 62 Developing device 64 Transfer roll (an example of a transfer device)
108 Cylindrical body 116 Supporting member 116A Separating part 116B Groove (an example of a first groove)
116G groove (an example of a second groove)
118 outer peripheral surface 120 inner peripheral surface 156 support member 156B groove (an example of a first groove)
160 Inner peripheral surface 166 Support member 166G Groove (example of second groove)
168 Outer peripheral surface 176 Support member 176B Groove (an example of a first groove)
176G groove (an example of a second groove)
178 Outer peripheral surface 180 Inner peripheral surface 300 Support member 300A Separation portion 300B Outer groove (an example of a first groove)
300C First inner groove (an example of the second groove)
300D Second inner groove (an example of a second groove)
302 Outer peripheral surface 306 Inner peripheral surface 308 Gate mark 310A First thick portion 312A Second thick portion 314A Gate mark 314B Gate mark

Claims (8)

Supported inside the cylindrical body that constitutes the image carrier,
An arcuate shape in which a separation portion extending in the axial direction of the cylindrical body is formed in a part in the circumferential direction,
The axial length is not more than half the axial length of the cylindrical body,
It is arranged on the central side in the axial direction of the cylindrical body,
A first groove portion formed on the opposite side of the separation portion with respect to the center of the cylindrical body and extending in the axial direction when viewed from the axial direction while being supported inside the cylindrical body,
In a state supported by the inside of the cylindrical body, when viewed from the axial direction, the pair of symmetrical members extend symmetrically with respect to a straight line passing through the spaced portion and the center of the cylindrical body, and extend in the axial direction. A groove,
A support member comprising: Supported inside the cylindrical body that constitutes the image carrier,
An arcuate shape in which a separation portion extending in the axial direction of the cylindrical body is formed in a part in the circumferential direction,
A first groove portion formed on the opposite side of the separation portion with respect to the center of the cylindrical body and extending in the axial direction when viewed from the axial direction while being supported inside the cylindrical body,
Formed on the inner peripheral side of the cylindrical body and having a symmetry with respect to a straight line passing through the separated portion and the center of the cylindrical body when viewed from the axial direction in a state supported by the inside of the cylindrical body. And a pair of second grooves extending in the axial direction,
A support member comprising: Supported inside the cylindrical body that constitutes the image carrier,
An arcuate shape in which a separation portion extending in the axial direction of the cylindrical body is formed in a part in the circumferential direction,
On the outer peripheral side of the cylindrical body, in a state supported inside the cylindrical body, when viewed from the axial direction, formed on the opposite side of the separated portion with respect to the center of the cylindrical body, the axial direction A first groove extending to
Formed on the inner peripheral side of the cylindrical body and having a symmetry with respect to a straight line passing through the separated portion and the center of the cylindrical body when viewed from the axial direction in a state supported by the inside of the cylindrical body. And a pair of second grooves extending in the axial direction,
A support member comprising: The support member according to claim 1, wherein the first groove portion is formed on an outer peripheral side, and the pair of second groove portions are formed on an inner peripheral side . A gate mark is formed on a portion of the outer surface located radially outward from the second groove portion, and a portion where the gate mark is located at a groove bottom formed between the second groove portion and the outer surface. The supporting member according to claim 3, wherein the supporting member is a thicker portion than other portions. The thick portion provided at the bottom of one of the second grooves and the thick portion provided at the bottom of the other second groove are shifted in the longitudinal direction of the second groove. Support members . A cylindrical body that holds an image on the surface in a cylindrical shape,
The support member according to any one of claims 1 to 6, which is supported inside the cylindrical body,
An image carrier comprising: An image carrier according to claim 7,
A charging device for charging the image holding member,
An exposure device that exposes the charged image carrier to form an electrostatic latent image,
A developing device for developing the electrostatic latent image formed on the surface of the image holding member as a toner image,
A transfer device for transferring the toner image to a recording medium,
An image forming apparatus comprising: