JP5056320B2 - Rotating body support structure and image forming apparatus - Google Patents

Description

  The present invention relates to a rotating body support structure and an image forming apparatus.

  Patent Document 1 discloses a technique in which a stainless steel washer is disposed between a rotating gear and a housing that supports the gear.

By placing a stainless steel washer on the part where the end face of the rotating gear and the housing rub, it is possible to prevent the gear from being worn by rubbing during rotation and to rotate the gear (rotating body) for a long time. Yes.
JP 2006-38132 A

  An object of the present invention is to reduce wear and smoothly rotate a rotating body over a long period of time.

  The rotating body support structure according to claim 1 of the present invention includes a rotating body that is rotatably supported, a support member that contacts the axial end of the rotating body and supports the rotating body, and the support member A friction portion that is provided at a position that contacts the end portion and is rubbed against the end portion by being filled with a lubricant, and a holding portion that is connected to the friction portion and holds the lubricant outside the position that contacts the end portion. And a lubricant reservoir portion in which is formed.

  The rotating body support structure according to a second aspect of the present invention is characterized in that, in the first aspect, the holding portion communicates with an external space.

  The rotating body support structure according to claim 3 of the present invention is characterized in that in claim 1 or 2, the end portion is provided with a diffusing means for diffusing the lubricant reservoir.

  The rotating body support structure according to claim 4 of the present invention is characterized in that, in claim 3, the diffusing means is a recess facing the lubricant reservoir.

  The rotating body support structure according to claim 5 of the present invention is the rotating body support structure according to claim 3 or 4, wherein the diffusing means communicates with an external space via the lubricant reservoir. Features.

  The rotating body support structure according to claim 6 of the present invention is the rotating body support structure according to claim 4 or 5, characterized in that the recess has a portion that does not face the lubricant reservoir. .

  The rotating body support structure according to claim 7 of the present invention is the rotating body support structure according to any one of claims 1 to 6, wherein the lubricant reservoir portion is a first annular groove constituting the friction portion. And the second annular groove provided outside the first annular groove and constituting the holding portion, and the second annular groove and the first annular groove are connected to each other by being recessed from a portion in contact with the end portion. A connecting portion, wherein the first and second annular grooves are concentric circles of the rotating body.

  An image forming apparatus according to an eighth aspect of the present invention includes the rotating body support structure according to any one of the first to seventh aspects, wherein the rotating body support structure transmits a driving force. To do.

  According to the configuration of the first aspect of the present invention, the lubricant consumed by the rotation of the rotating body is supplied from the holding unit, and a lubricating effect is obtained as compared with the case where the present configuration is not provided. And the wear of the support member is reduced, and the rotating body can be smoothly rotated over a long period of time.

  According to the configuration of the second aspect of the present invention, the lubricant can be filled from the outside space, the assembling property and workability can be improved, and the lubricant can be easily replenished according to the amount of lubricant consumed. .

  According to the configuration of the third aspect of the present invention, the lubricant can be supplied uniformly by diffusing the lubricant. Further, the supply of the lubricant from the holding unit to the friction unit is promoted.

  According to the configuration of the fourth aspect of the present invention, the concave portion captures the lubricant and diffuses, whereby a lubricating effect can be obtained.

  According to the fifth aspect of the present invention, the lubricant can be filled into the diffusing means from the external space, and the assemblability and workability are improved and the lubricant is easily replenished according to the amount of lubricant consumed. can do.

  According to the configuration of the sixth aspect of the present invention, the lubricant in the concave portion of the facing portion is pulled by the rotation of the rotating body, and the lubricant is supplied to the concave portion of the facing portion.

  According to the configuration of the seventh aspect of the present invention, the friction portions are evenly contacted regardless of the rotational position of the rotating body, and the lubricant is evenly supplied from the holding portion via the connection portion.

  According to the structure of Claim 8 of this invention, since a rotary body is rotated with the rotational force transmitted by the rotary body support structure in any one of Claim 1-7, it does not have this structure. As compared with the image forming apparatus, wear is reduced, and the rotating body can be smoothly rotated over a long period of time.

  An example of an embodiment according to the present invention will be described with reference to the drawings.

  In the present embodiment, an example adopted in an image forming apparatus as an example of a rotating body support structure will be described with reference to FIGS.

<Overall configuration>
First, the overall configuration of the image forming apparatus according to the present embodiment will be described.

  As illustrated in FIG. 10, the image forming apparatus 10 includes a housing 12, and a sheet material supply device 14 is disposed in the lower portion of the housing 12. In addition, a discharge unit 16 that discharges a sheet material on which an image is formed is formed on the top of the housing 12.

  Further, the sheet material supply device 14 is provided with a detachable paper feed cassette 18, and the sheet material P is stacked and accommodated in the paper feed cassette 18. Further, the paper feed cassette 18 is provided with a bottom plate 20. When the paper feed cassette 18 is attached to the sheet material supply device 14, the bottom plate 20 is moved upward by an elevating means (not shown) and is The sheet material P laminated on the sheet is pressed against the pickup roll 22. Further, when the paper feeding cassette 18 is pulled out from the housing 12, the bottom plate 20 is moved downward by the lifting means to replenish the paper feeding cassette 18 with the sheet material P.

  Next to the pickup roll 22, a paper feed roll 24 and a separation roll 26 are provided for conveying the sheet material P sent out by the pickup roll 22 one by one.

  In addition, a registration roll 28 that temporarily stops the sheet material P and passes between a later-described photosensitive unit 30 and a transfer unit 32 at a predetermined timing is provided on the downstream side of the sheet material conveyance path of the sheet feeding roll 24. Yes.

  Further, a photosensitive unit 30, a transfer unit 32, a fixing device 36, and the like are provided between the registration roll 28 and the discharge unit 16, and a power supply unit 41 for driving and controlling them in the other housing 12. , And a control unit 44 is arranged. The photosensitive unit 30 is provided with a photosensitive frame 46, and four photosensitive drums 40 are rotatably supported on the photosensitive frame 46.

  An exposure device 62 that writes a latent image on the photoconductor drum 40 with a laser beam is disposed on the back side of the photoconductor unit 30 at a position corresponding to each photoconductor drum 40 and is charged by a charging device 48 described later. A latent image is formed by irradiating the photosensitive drum 40 with a laser.

  Further, around each photosensitive drum 40, a latent image written on each photosensitive drum 40 by an exposure device 62 and a charging device 48 provided with a charging roll for charging the photosensitive drum 40 like a developer. Development unit 50 that develops a toner image with (toner), neutralization device 52 that neutralizes the photoreceptor drum 40 after transfer, and development that removes the developer (toner) remaining on the photoreceptor drum 40 after transfer. A cleaning device 54 is provided as agent removal means.

  The photoconductor unit 30 is a unit in which four photoconductor drums 40, a charging device 48, a developing unit 50, a charge removal device 52, and a cleaning device 54 are held by a photoconductor frame 46 and integrated. It is detachable with respect to.

  The details of a rotation support structure for a gear, which is an example of a rotating body that transmits a rotational force to the photosensitive drum 40, will be described later.

  On the other hand, the four toner boxes 56 corresponding to the four developing units 50 are connected to the back side of the photoreceptor unit 30. The toner box 56 is for magenta, yellow, cyan, and black, and includes a toner supply unit 58 and a toner collection unit 60 that are integrated. Further, the toner supply unit 58 is connected to the developing unit 50 and supplies toner of each color to the developing unit 50. The toner collection unit 60 is connected to the cleaning device 54 and collects toner of each color.

  The transfer unit 32 is disposed on the front side of the photoconductor unit 30 so as to face the photoconductor unit 30. The transfer unit 32 has two support rolls 64 provided in the vertical direction, a transport belt 66 wound around the two support rolls 64, and the photosensitive drums 40 across the transport belt 66. A transfer roll 68 provided at the position is provided. As a result, the sheet material P is nipped and conveyed by the photosensitive drum 40 and the transfer roll 68 so that the toner image formed on the photosensitive drum 40 is transferred to the sheet material P.

  Further, downstream of the photoreceptor unit 30, a fixing device 36 that fixes the toner image transferred to the sheet material P to the sheet material P, and a discharge roll 38 that discharges the sheet material P on which the toner image is fixed to the discharge unit 16. Is provided.

<Operation of Image Forming Apparatus>
Next, the operation of the image forming apparatus 10 will be described.

  First, the charging device 48 negatively charges the surface of the photosensitive drum 40 with a predetermined charging portion potential. Further, the exposure device 62 exposes the surface of the photosensitive drum 40 so that the charged image portion on the photosensitive drum 40 has a predetermined exposure portion potential, thereby forming an electrostatic latent image.

  That is, on the basis of image data supplied from the control unit 44, a latent image corresponding to an image is formed on each photoconductive drum 40 by turning on and off a semiconductor laser (not shown) and performing modulation.

  Further, when the electrostatic latent image on the rotating photosensitive drum 40 passes through the developing unit 50, the toner of the developer G stored in the developing unit 50 adheres to the electrostatic latent image by electric force, and the electrostatic latent image Is visualized as a toner image.

  Therefore, the sheet material P placed on the paper feed cassette 18 is sent out by the pickup roll 22 and further conveyed one by one by the paper feed roll 24 and the separation roll 26 that are rotationally driven. The sheet material P is temporarily stopped by the resist roll 28 and is sent out between the photosensitive unit 30 and the transfer unit 32 at a predetermined timing. The sheet material P is held by the conveyance belt 66 and conveyed to the transfer unit 34 of each photoconductor drum 40, and the toner images on the photoconductor drum 40 are sequentially applied to the sheet material P when passing through the transfer unit 34. After being transferred, a color image is formed on the sheet material P.

  The toner image transferred to the sheet material P is fixed by the fixing device 36, and the sheet material P is discharged to the discharge unit 16 by the discharge roll 38.

<Rotating body support structure>
Next, a rotating body support structure for a gear, which is an example of a rotating body that transmits a rotational force to the photosensitive drum 40, will be described.

  As shown in FIG. 4, the photoconductor frame 46 on which the photoconductor drum 40 is supported is formed, for example, by filling a synthetic resin such as an ABS resin with a filler such as a glass fiber.

  As shown in FIG. 8, the housing 70 attached to the photoconductor frame 46 is made of sheet metal, and metal studs 72 to 82 are fixed to the housing 70 by caulking or the like.

  Further, the housing 70 is provided with a circular opening 84 through which a drive shaft of a drive motor 88 described later is inserted.

  Further, as shown in FIG. 6, a first reduction helical gear 92 that meshes with the drive gear 90 of the drive motor 88 is rotatably supported by the stud 74 that is arranged second from the end. The first reduction helical gear 92 includes a helical gear 92A having a large diameter and a helical gear 92B having a small diameter.

  Further, a second reduction helical gear 94 including a helical gear 94A that meshes with a small helical gear 92B of the first reduction helical gear 92 is rotatably supported on the stud 72 disposed at the end. The second reduction helical gear 94 includes a helical gear 94A having a large diameter and a helical gear 94B having a small diameter.

  The first reduction helical gear 92 and the second reduction helical gear 94 are formed by molding with a highly slidable resin such as polyacetal.

  Further, as shown in FIG. 7, the small helical gear 94 </ b> B of the second reduction helical gear 94 is meshed with a driven helical gear 98 provided at the end of the photosensitive drum 40. 40 is rotationally driven.

  On the other hand, as shown in FIG. 2, the front end of the stud 72 provided in the housing 70 is fitted into the insertion hole 102 provided in the photoconductor frame 46.

  Further, the second reduction helical gear 94 (rotary body) is provided with a cylindrical portion 94C through which the stud 72 (shaft) passes, and the end of the cylindrical portion 94C projects against the photoreceptor frame 46 (support member). An abutting surface 94D (end portion) to be applied is provided.

As shown in FIG. 3, the abutment surface of the second reduction helical gear 94 94D seating surface 104 (supporting member) in (see FIG. 2) is abutted photoreceptor frame 46, grease 1 09 as a lubricant A concave grease reservoir 106 (lubricant holding portion) filled with (see FIG. 2) is provided. In this embodiment, the grease 109 having a viscosity of 1050 cs (centipoise) at 40 ° C. of the base oil clay is used as an example so that the grease 109 is not scattered.

  As shown in FIG. 1, the grease reservoir 106 includes a first annular groove 106A provided so as to surround the insertion hole 102, and a second annular groove 106B provided so as to surround the first annular groove 106A. A connecting portion 106C that is recessed from the abutment surface 94D and connects the second annular groove 106B and the first annular groove 106A. The first annular groove 106A, the second annular groove 106B, and the connecting portion 106C The same rotation center as the rotation center of the second reduction helical gear 94 is shared.

Further, in this embodiment, the first annular groove 106A is provided at a position where it abuts with the end portion in the rotation axis direction of the second reduction helical gear 94, and is filled with grease 109 to constitute the friction portion 110. The groove 106B is connected to the first annular groove 106A via the connecting portion 106C, holds the grease 109 at a position where it does not contact the end portion in the rotation axis direction of the second reduction helical gear 94, and constitutes the holding portion 108. .

Furthermore, the holding part 108 has an open part 112 communicating with the external space, and the open part 112 is in contact with air. Depending on the consumption amount of the grease 109 from the opening portion 112, filling is appropriately performed.

  Further, the seat portion 104A of the seat surface 104 with which the abutting surface 94D comes into contact is recessed from the general surface of the seat surface 104, and the tip portion of the cylindrical portion 94C enters the grease reservoir portion 106.

On the other hand, as shown in FIG. 5, the abutting surface 94D of the second reduction helical gear 94 is provided with a concave circular recess 118 as an example of a diffusing means for diffusing the grease 109 .

  Specifically, as shown in FIG. 1, a part of the circular recess 118 faces the grease reservoir 106, and the other part of the circular recess 118 faces the seat 104 </ b> A of the seat surface 104. The position of the recess 118 is determined. Furthermore, the circular recess 118 communicates with the external space through the first annular groove 106A, the connecting portion 106C, the second annular groove 106B, and the opening portion 112 in this order.

  Next, the operation of the rotation support structure in which the second reduction helical gear 94 is supported on the seat surface 104 of the photoconductor frame 46 will be described.

  As shown in FIGS. 7 and 9, when the drive motor 88 is rotationally driven, the rotational drive force of the drive motor 88 is photosensitive via the first reduction helical gear 92 and the second reduction helical gear 94. It is transmitted to the body drum 40. As a result, a force in the thrust direction F acts on the first reduction helical gear 92 and the second reduction helical gear 94 as it rotates, and the second reduction helical gear 94 is applied to the photosensitive frame 46. A thrust force F acts on the surface. Then, the abutment surface 94D of the second reduction helical gear 94 is rubbed against the photoconductor frame 46.

  However, in this embodiment, as shown in FIG. 3, the seat surface 104 of the photoconductor frame 46 is provided with a grease reservoir 106 including a first annular groove 106A and a second annular groove 106B. As shown in FIG. 4, a circular recess 118 is provided on the abutment surface 94 </ b> D of the second reduction helical gear 94.

Accordingly, when the second reduction helical gear 94 rotates, the grease 109 is consumed (evaporated and deteriorated) by the cylindrical portion 94C of the second reduction helical gear 94 and the friction portion 110 where the abutting surface 94D and the grease 109 rub against each other. The However, the grease 109 that fills the second annular groove 106 and constitutes the opening portion 112 is supplied to the first annular groove 106A through the connection portion 106C. Thereby, the grease 109 consumed by the friction part 110 is replenished.

The circular recess 118 provided on the abutting surface 94D captures the grease 109 filled in the grease reservoir 106 and rotates the second reduction helical gear 94 so that the grease filled in the circular recess 118 is rotated. 109 is diffused to the seat 104A. Further, the supply of the lubricant from the holding unit 108 to the friction unit 110 is promoted by the rotation.

Here, as described above, a part of the circular recess 118 faces the grease reservoir 106, and the other part of the circular recess 118 faces the seat 104 </ b> A of the seat surface 104. For this reason, the grease 109 filled in the circular recess 118 from the portion facing the grease reservoir 106 is diffused directly to the seat 104 </ b> A of the photoconductor frame 46.

Further, in the seat 104A, the grease 109 is diffused in a portion not facing the rotating circular recess 118 by capillary action with rotation. That is, the grease 109 in the circular recess 118 in the facing portion is pulled by the rotation of the rotating body, and the grease 109 is diffused to the facing portion (seat portion 104A).

In the assembly of the image forming apparatus according to the present embodiment, the second reduction helical gear 94, the stud 72, and the like are assembled on the seating surface 104 of the photoconductor frame 46, and finally the grease is released from the opening portion 112. 109 can also be filled.

  Although the present invention has been described in detail with respect to specific embodiments, the present invention is not limited to such embodiments, and various other embodiments are possible within the scope of the present invention. It is clear to the contractor. For example, although the above embodiment has been described using a gear as an example of a rotating body, other rotating bodies such as pulleys and sprockets may be used.

  In the above embodiment, the photosensitive drum is used as an example of the member that transmits the drive by the rotating body. However, the rotating body is another rotating member such as a transfer roll, a developing roll, a transport roll, and a fixing roll. Also good.

It is an expanded sectional view showing a rotating body support structure concerning an embodiment of the present invention, and showing a grease storage part, a circular crevice, etc. FIG. 4 is a cross-sectional view illustrating a rotating body support structure according to an embodiment of the present invention and showing a bearing surface of a photoconductor frame, a second reduction helical gear, and the like. FIG. 5 is an enlarged perspective view showing a seating surface of a photoconductor frame in a rotating body support structure according to an embodiment of the present invention. FIG. 2 is a perspective view showing a rotating body support structure according to an embodiment of the present invention and showing a photosensitive frame, a seating surface of the photosensitive frame, a photosensitive drum, and the like. It is the expansion perspective view showing the rotating body support structure concerning the embodiment of the present invention, and showing the abutting surface of the 2nd reduction helical gear. It is a perspective view showing a rotating body support structure according to an embodiment of the present invention and showing each reduction helical gear, a drive motor, and the like. It is the front view showing the rotary body support structure concerning the embodiment of the present invention, and showing each reduction helical gear, a drive motor, etc. It is the perspective view which showed the housing to which each reduction gearwheel gear used for the rotary body support structure which concerns on embodiment of this invention is attached. FIG. 2 is a perspective view showing a rotating body support structure according to an embodiment of the present invention, and showing a photosensitive frame, a driving motor, a photosensitive drum, and the like. 1 is a schematic configuration diagram illustrating an image forming apparatus employing a rotating body support structure according to an embodiment of the present invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Image forming apparatus 40 Photosensitive drum 46 Photosensitive body frame (support member)
72 Stud (shaft member)
94 Second reduction helical gear (rotating body)
94D Abutting surface 106 Grease reservoir 106A First annular groove 106B Second annular groove 106C Connection part 110 Friction part 112 Open part 118 Circular recess (diffusion means)

Claims (8)

A rotating body that is rotatably supported;
A support member that contacts the axial end of the rotating body and supports the rotating body;
Provided at a position where the end of the support member comes into contact with the end, and a friction part that is filled with a lubricant and rubs against the end, and holds the lubricant outside the position that is connected to the friction and comes into contact with the end A holding part, a lubricant reservoir part formed with,
A rotating body support structure comprising:   The rotating body support structure according to claim 1, wherein the holding portion communicates with an external space.   The rotating body support structure according to claim 1, wherein the end portion is provided with a diffusing means for diffusing the lubricant reservoir.   The rotating body support structure according to claim 3, wherein the diffusing means is a recess facing the lubricant reservoir.   5. The rotating body support structure according to claim 3, wherein the diffusing unit communicates with an external space via the lubricant reservoir.   The rotating body support structure according to claim 4 or 5, wherein the concave portion includes a portion that does not face the lubricant reservoir. The lubricant reservoir portion includes a first annular groove that constitutes the friction portion;
A second annular groove provided outside the first annular groove and constituting the holding portion;
A connection portion that is recessed from a portion that contacts the end portion and connects the second annular groove and the first annular groove;
The rotating body support structure according to any one of claims 1 to 6, wherein the first and second annular grooves are concentric circles of the rotating body. The rotating body support structure according to any one of claims 1 to 7,
The image forming apparatus according to claim 1, wherein the rotating body support structure transmits a driving force.