JP2002303337A - Driving transmitting device and image forming device provided with it - Google Patents

Abstract

PROBLEM TO BE SOLVED: To simplify design of a driving transmitting device using a clutch, to secure inexpensive and sufficient strength and to securely prevent a clutch on a rotation axis from rotating with the rotation axis. SOLUTION: A plurality of gear shafts 11 are integrally formed on a resin frame 10 provided in a device body of an image forming device, gears 12 are provided at the gear shaft. A rotation axis 20 is provided through the resin frame, and a clutch 16 and a clutch gear 12a having an outer diameter 'd' larger than the diameter 'D' of the clutch 16 are rotatably provided at some of the rotation axes. In the clutch gear, a gear train 13 is constituted with the gear 12. In the meantime, a rising piece 24 is integrally formed in parallel with the rotation axis 20, and an engagement part 25 engaged with the clutch for preventing its rotation is provided at the rising piece.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] 1. Field of the Invention [0002] The present invention relates to an image forming apparatus such as a copier, a facsimile, a printer, or a multifunction peripheral thereof. Also, for example, in such an image forming apparatus, the present invention relates to a drive transmission device that transmits a driving force of a drive motor to an image carrier, a developing device, a toner replenishing device, a paper feed roller, a transport roller, a registration roller, a fixing device, and the like.

[0002]

2. Description of the Related Art Conventionally, in a drive transmission device of an image forming apparatus, when a clutch is present in a gear train, for example, as shown in FIG. Was separately attached to the frame 5 with the mounting screw 4, thereby preventing the clutch 1 from rotating on the rotating shaft 6.

However, in such a conventional drive transmission device, since the metal detent member 3 is provided separately from the metal frame 5, the number of parts increases, the cost increases, and the weight increases. there were.

Therefore, in a conventional drive transmission device, as shown in FIG. 8, for example, a cylindrical portion 7 is formed integrally with a resin frame 5, and the cylindrical portion 7 has a notch in a part of the outer periphery. 7a
And an inwardly protruding engagement portion 7 on the inner surface.
In some cases, b is formed linearly in the axial direction, and the rotary shaft 6 is inserted into the cylindrical portion 7 through the resin frame 5 from the inner surface side.

[0005] The rotating shaft 6 is inserted through a center hole of a clutch gear 8 constituting a gear train (not shown).
Of the clutch gear 8 inserted in the center of the
And the clutch 1. And the clutch gear 8
Are engaged with other gears constituting the gear train through the notch 7a, and the clutch 1 is engaged with the locking groove 2a of the projection 2 thereof.
The rotation is prevented by inserting the engaging portion 7b into the inside.

The clutch 1 transmits the rotation of the clutch gear 8 to the rotating shaft 6 by energizing the clutch gear 1, and stops the energization of the clutch gear 8 by energizing the clutch gear 8.
The transmission of rotation from the shaft to the rotating shaft 6 is interrupted.

As described above, the clutch 1 is mounted on the resin frame 5.
The engagement portion 7b that engages with and prevents the rotation of the clutch 1 is formed by integral molding. For example, in a drive transmission device used in an image forming apparatus, the clutch 1 is detented without providing an independent clutch detent member. The number of parts can be reduced, and the weight of the frame 5 integrally formed with the engaging portion 7b can be reduced by using a resin material.

[0008]

However, in the conventional drive transmission device as shown in FIG. 8, since the resin frame 5 must be made of a hard material, it is made of glass fiber-containing polyphenylene ether (PPE) or the like. I was
Then, in order to maintain sufficient strength, the portion for stopping the rotation of the clutch 1 is formed in a cylindrical shape to form the cylindrical portion 7.

However, this has the following problems. There is a restriction that the outer diameter of the clutch gear 8 must be smaller than the outer diameter of the clutch 1 so that the clutch 1 can be housed in the cylindrical portion 7.

In order to engage another gear with the clutch gear 8, a notch 7 a must be provided in the cylindrical portion 7, which complicates the shape, increases the mold cost, and increases the cost.

When the clutch gear 8 meshes with a plurality of gears, the notches 7a must be enlarged or the number thereof increased, and the strength of the cylindrical portion 7 decreases.

The gear meshing with the clutch gear 8 must be prevented from hitting the clutch 1, and the thrust direction of the gear meshing with the clutch gear 8 is regulated.

Accordingly, a first object of the present invention is to provide a drive transmission device using a clutch which solves these problems, simplifies design, secures sufficient strength at a low cost, and provides a rotary shaft. The object of the present invention is to reliably prevent the clutch on the rotating shaft from rotating together.

A second object of the present invention is to provide a drive transmission device using a clutch, which restricts the movement of the clutch in the thrust direction of the rotary shaft without separately providing an E-ring or a snap ring, thereby reducing the number of parts. And to reduce the weight.

[0015] A third object of the present invention is to facilitate attachment and detachment of a clutch to and from a resin frame.

A fourth object of the present invention is to prevent the clutch from rotating without increasing the size of the drive transmission device using the clutch.

A fifth object of the present invention is to prevent the strength of the resin frame from being significantly reduced.

A sixth object of the present invention is to provide an image forming apparatus provided with a drive transmission device which has achieved the above-mentioned objects.

[0019]

In order to achieve the first object, the invention according to the first aspect has a clutch and an outer diameter larger than the outer diameter on a rotating shaft passing through a resin frame. In a drive transmission device including a clutch gear, a rising piece is formed integrally with the resin frame, and the rising piece is provided with an engaging portion that engages with the clutch to prevent rotation thereof. It is characterized by.

According to a second aspect of the present invention, there is provided a drive transmission device including a clutch and a clutch gear having an outer diameter larger than the outer diameter on a rotating shaft passing through the resin frame to achieve the second object. , A rising piece is formed on the resin frame by integral molding, and the rising piece is provided with an engaging portion that engages with a clutch and regulates movement in the thrust direction.

According to a third aspect of the present invention, in order to achieve the third object together with the first or second object, the drive transmission device according to the first or second aspect,
The clutch is engaged with or released from the clutch using the elasticity of the rising piece.

According to a fourth aspect of the present invention, the first to third aspects described above.
In order to achieve the fourth object together with any one of the above objects, in the drive transmission device according to claim 1, 2 or 3, the engagement portion where the engagement portion engages with the clutch is located inside the outer diameter of the clutch gear. Characterized in that it is provided in

According to a fifth aspect of the present invention, there is provided the first to fourth aspects.
In order to achieve the fifth object together with any one of the above objects, the drive transmission device according to any one of claims 1, 2, 3, and 4, wherein a reinforcing rib is formed on the resin frame.

According to a sixth aspect of the present invention, there is provided an image forming apparatus for achieving the sixth object.
A drive transmission device according to 2, 3, 4, or 5 is provided.

[0025]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 shows a schematic internal configuration of a laser copying machine.

In the figure, reference numeral 50 denotes a copying machine main body.
An automatic document feeder 53 is mounted on the apparatus main body 50 so as to cover the contact glass 52 on the image reader 51 so as to be freely opened and closed.

When making a copy with this laser copying machine, an original is set on the automatic original feeder 53 and
Alternatively, the automatic document feeder 53 is opened, the document is directly set on the contact glass 52, and a start switch provided on an operation unit (not shown) is pressed.

Then, when a document is set on the automatic document feeder 53, the contents of the document conveyed onto the contact glass 52 by the automatic document feeder 53 or when the document is directly set on the contact glass 52 Then, the content of the document on the contact glass 52 is read by the image reading device 51.

Further, the drum-shaped image carrier 55 is rotated clockwise, and the surface thereof is uniformly charged by the charging device 56. Next, writing is performed by irradiating a laser beam with an optical writing device 57 in accordance with the contents read by the image reading device 51, and an electrostatic latent image is formed on the surface of the image carrier 55. Thereafter, toner is adhered by the developing device 58 to visualize the electrostatic latent image,
An image is formed on the image carrier 55.

On the other hand, the sheet is fed from the sheet cassette 61 by rotating the sheet feeding roller 60, conveyed by the conveying roller 63 through the conveying path 62, and the leading end thereof is pressed against the registration roller 64. Alternatively, the manual feed sheet is fed from above the manual feed tray 66 by rotating the paper feed roller 65, conveyed through the conveyance path 62, and the leading end thereof is pressed against the registration roller 64.

Then, the registration roller 64 is rotated in synchronization with the above-mentioned image on the image carrier 55, and the sheet is fed under the image carrier 55 to be transferred to the transfer / conveyance device 67.
To transfer the image on the image carrier 55 to a sheet. The image-transferred sheet is conveyed by the transfer / conveyance device 67 and is transferred to the fixing device 6.
Then, the transfer image is fixed by the fixing device 68 and discharged to the outside of the copier main body 50 by the discharge roller 69.

When an image is to be formed on the back side of the sheet, the sheet after the image is fixed is placed in the double-sided recording device 70, and then reversed and re-entered in the conveying path 62, and the image formed on the image carrier 55 is formed separately. After the image is fixed on the back surface of the copier and the transferred image is fixed, the sheet on which double-side recording has been performed is discharged to the outside of the copying machine main body 50 by the discharge roller 69.

After transferring the image, the surface of the image bearing member 55 is cleaned by a cleaning device 71 to remove the residual toner, and is then discharged by a discharging device (not shown) to prepare for the next image formation starting from charging.

In the illustrated laser copying machine, as shown in FIG. 2, a pair of resin frames 10 are attached to and fixed to a base frame (not shown) at the front and rear inside the copying machine main body 50 so as to face each other. And these frames 1
In the interval 0, the image carrier 55, the charging device 56, the optical writing device 57, the developing device 58, the paper feed rollers 60 and 65, the transport rollers 63, the registration rollers 64, and the transfer transport device 6
7, fixing device 68, discharge roller 69, double-sided recording device 7
0, and supports the cleaning device 71 and the like.

FIG. 3 shows one of a pair of resin frames 10 to which the drive transmission device according to the present invention is attached.

The resin frame 10 is made of polybutylene terephthalate (PBT), and a gear shaft 11 is appropriately formed on the outside by integral molding. A gear 12 is rotatably attached to each gear shaft 11.

The resin frame 10 is provided with a rotating shaft 20 penetrating therethrough. Then, the above-described gear 12 and a clutch gear 1 to be attached to the rotation shaft 20 thereof, for example, will be described later.
The gear train 13 is constituted together with 2a and the like. This gear train 1
3, the drive force of a drive motor (not shown) is applied to the image carrier 55, the developing device 58, and the developing device 5 (not shown).
8, a toner supply device for supplying toner,
65, a transfer roller 63, a registration roller 64, a fixing device 68 and the like.

In the illustrated example, a plurality of gears 1 constituting the gear train 13 are mounted on a resin frame 10 holding the gear train 13.
Since the second gear shaft 11 is formed by integral molding, the drive transmission device can rotatably support the gear 12 without providing an independent gear shaft, thereby reducing the number of parts and a frame having the gear shaft 11 integrally. 10 can be made of a resin material to reduce the weight.

Further, in the illustrated example, since the reinforcing ribs 14 are integrally formed around the resin frame 10 to form a box shape as a whole, the strength is increased and the strength of the frame is greatly increased by using a resin material. It can be prevented from lowering. Of course, the reinforcing ribs 14 are
Not limited to the periphery of the resin frame 10, but may be appropriately provided in other portions of the resin frame 10.

By the way, in the example shown in FIG.
And a clutch 16. The clutch 16 is rotatably provided on a rotating shaft 20 that penetrates the resin frame 10 together with the clutch gear 12a. The outer diameter d of the clutch gear 12a is larger than the outer diameter D of the clutch 16.

Here, the clutch 16 is provided on a rotating shaft such as a toner supply roller for supplying toner to the developing device 58, a paper supply roller 60/65, or a conveyance roller 63, which needs to control rotation or rotation stop.

FIG. 4A shows another example of a state in which the clutch 16 is attached to the resin frame 10. (B) shows a part of the resin frame 10. (C)
The case where the clutch 16 is attached to and detached from the resin frame 10 is shown.

In the example shown in FIG.
In addition, a rising piece 24 is formed integrally with the outer plate surface so as to be perpendicular to the outer plate surface so as to be parallel to the rotating shaft 20, and an engaging portion 25 protruding from the tip thereof is provided. , A through hole 26 is opened. Then, the rotating shaft 20 inserted from the inside into the through hole 26 is inserted into the center hole of the clutch gear 12 a constituting the gear train 13, and is also inserted into the center of the clutch 16. Gear 12a and clutch 16
I support.

Then, the starting piece 24 is made longer,
As shown in FIG. 4 (C), by bending using its own elasticity, the engaging portion 25 is engaged in the locking groove 22 of the protrusion 21 of the clutch 16 to prevent the clutch 16 from rotating. .
When the clutch 16 is removed from the resin frame 10, (A) the rising piece 24 is bent as indicated by a chain line, and the engagement of the engaging portion 25 of the rising piece 24 with the projection 21 of the clutch 16 is released. .

In the illustrated example, since the engaging portion 25 is engaged with or released from the clutch 16 by utilizing its own elasticity, the mounting screw is fastened or the fastening is released. In addition, the number of parts can be reduced by eliminating mounting screws and the like, and the clutch 16
Can be easily attached and detached.

In the illustrated example, by increasing the height h of the engaging portion 25, the engaging position at which the engaging portion 25 engages with the clutch 16 is provided inside the outer diameter of the clutch gear 12a. As a result, the clutch 1 can be increased without increasing the size.
6 can be stopped.

By the way, in the example shown in FIG.
, The rotation of the clutch 16 cannot be restricted, but the movement of the clutch 16 in the thrust direction of the rotating shaft 20 cannot be restricted. Therefore, when it is desired to regulate even the movement in the thrust direction, as shown in FIG.
5 has a mouth shape, and the protrusion 21 of the clutch 16 is inserted into the engagement portion 25.

In the example shown in FIG. 5, the engaging portion 25 that engages with the clutch 16 and regulates the movement in the thrust direction (the direction of the arrow a in the figure) is integrally formed on the resin frame 10 as described above. Therefore, the rotation of the clutch 16 can be prevented by the engaging portion 25 and the movement in the thrust direction can also be restricted. The movement in the thrust direction a can be restricted without providing an E-ring or a retaining ring. A frame 1 having a reduced number of parts and integrally having an engaging portion 25
0 can be made of a resin material to reduce the weight.

In the example shown in FIG. 6, a cage-shaped engaging portion 28 is integrally formed on the outside of the resin frame 10, and through holes 29 and 30 are formed at opposing positions, and the window 3 is formed on the outer periphery.
1 is provided. Then, the rotating shaft 20 passing through the through holes 29 and 30 is inserted into the clutch gear 12a and inserted into the clutch 16, and the clutch gear 12a and the clutch 16 are housed and supported in the engagement portion 28. At this time, the protrusion 21 of the clutch 16 is put into the window 31.

With such a structure, the rotation of the clutch 16 is prevented by the window 31 of the engaging portion 28, and the thrust direction of the clutch 16 is controlled by the resin frame 10 in which the engaging portion 28 is formed. a) can be restricted, and the movement in the thrust direction a can be restricted without providing an additional E-ring or retaining ring, thereby reducing the number of parts and the frame 1 having the engaging portion 28 integrally.
0 can be made of a resin material to reduce the weight.

[0051]

As described above, according to the first aspect of the present invention, a rising piece is formed integrally with the resin frame, and the rising piece is engaged with the clutch to prevent its rotation. Since the engaging portion is provided, in the drive transmission device using the clutch, the clutch is prevented from rotating by the rising piece without providing the independent clutch detent member, thereby reducing the number of parts and a frame having the engaging portion integrally. Can be made of a resin material to reduce the weight.

Further, since the rising piece for stopping the rotation of the clutch does not cover around the clutch gear, the clutch gear can be made larger than the clutch without being restricted by the outer diameter of the clutch gear. The frame shape is not complicated, the resin frame can secure sufficient strength, and the outer diameter of the clutch gear is larger than that of the clutch. it can.

This makes it easy to design, secures sufficient strength at low cost, and reliably prevents the clutch on the rotating shaft from rotating together with the rotating shaft.

According to the second aspect of the present invention, a rising piece is formed on the resin frame by integral molding, and the rising piece is provided with an engaging portion that engages with the clutch and regulates the movement in the thrust direction. Therefore, in the drive transmission device using the clutch, the movement of the clutch in the thrust direction of the rotating shaft is restricted without providing an E-ring or a retaining ring, thereby reducing the number of parts and integrally forming the engaging portion. The frame can be made of a resin material to reduce the weight.

According to the third aspect of the present invention, the engaging portion is
Since the clutch engages or disengages the clutch by utilizing the elasticity of the rising piece, in addition to the effects of the above-described invention of claim 1 or 2, the mounting screw is fastened or the fastening is released. This eliminates the need for mounting screws and the like, thereby reducing the number of components and facilitating attachment and detachment of the clutch to and from the frame.

According to the fourth aspect of the present invention, the engagement position at which the engagement portion engages with the clutch is provided inside the outer diameter of the clutch gear. In addition to the effect, the clutch can be prevented from rotating without increasing the size.

According to the fifth aspect of the present invention, since the reinforcing rib is formed on the resin frame, in addition to the effects of any of the first to fourth aspects of the present invention, the strength is increased and the metal frame is replaced with a metal material. By using the resin material, it is possible to prevent the strength of the frame from being greatly reduced.

According to a sixth aspect of the present invention, an image forming apparatus includes the drive transmission device according to any one of the first, second, third, fourth, and fifth aspects. Image forming apparatus can be provided.

[Brief description of the drawings]

FIG. 1 is a schematic diagram showing the internal configuration of a laser copying machine.

FIG. 2 is a perspective view of a pair of resin frames provided in the copying machine main body.

FIG. 3 is an exploded perspective view of the drive transmission device according to the present invention, which is attached to one of the resin frames.

FIG. 4A is a perspective view showing a state in which a clutch is attached to the resin frame. (B) is a partial perspective view of the resin frame. (C) is a perspective view explaining the case where a clutch is attached to and detached from a resin frame.

FIG. 5 is a perspective view of another example of a state in which a clutch is attached to a resin frame.

FIG. 6A is a perspective view of still another example of a state in which a clutch is attached to a resin frame. (B) is a longitudinal sectional view of the resin frame.

FIG. 7 is a partial perspective view of a conventional drive transmission device including a clutch.

FIG. 8 is a partial perspective view of another conventional drive transmission device including a clutch.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Resin frame 12 Gear 14 Reinforcement rib 16 Clutch 20 Rotating shaft 24 Start-up piece 25 Engagement part D Outer diameter of clutch d Outer diameter of clutch gear a Thrust direction

Continued on front page F term (reference) 2C058 AC08 AF17 AF29 BA12 2H071 CA02 CA05 DA08 DA12 DA15 DA22 DA23 3F049 DA12 EA01 LA01 LB03 3J056 AA62 BE01 BE09 GA11

Claims (6)

[Claims] 1. A drive transmission device comprising a clutch and a clutch gear having an outer diameter larger than an outer diameter of a rotating shaft passing through a resin frame, wherein a rising piece is formed integrally with the resin frame. A drive transmission device comprising: a rising piece provided with an engagement portion that engages with the clutch to prevent rotation thereof. 2. A drive transmission device comprising a clutch and a clutch gear having an outer diameter larger than its outer diameter on a rotating shaft penetrating the resin frame, wherein a rising piece is formed integrally with the resin frame. A drive transmission device comprising: a rising piece provided with an engagement portion that engages with the clutch and regulates movement in a thrust direction thereof. 3. The drive transmission device according to claim 1, wherein the engagement portion is engaged with or released from the clutch using the elasticity of the rising piece. 4. The drive transmission device according to claim 1, wherein an engagement position at which the engagement portion engages with the clutch is provided inside an outer diameter of the clutch gear. 5. The drive transmission device according to claim 1, wherein a reinforcing rib is formed on the resin frame. 6. An image forming apparatus comprising the drive transmission device according to claim 1, 2, 3, 4, or 5.