JP2000194245A - Image forming device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve the transfer deviation of an image by a very simple constitution and also to satisfy all of the compactification of a device main body, the reduction of a cost, the improvement of a service performance or the like by a simple constitution. SOLUTION: Relating to the image forming device, driving force from a motor (driving source) provided for an image forming device main body is transmitted to a fixing feeding unit 126 attachably/detachably provided for the image forming device main body through gears (motive power transmitting means) 145 and 147. In this case, the motor can be moved profiling the position of the fixing feeding unit each time when the fixing feeding unit 126 is attached to the image forming device main body. Thus, the transfer of motive power to the fixing feeding unit 126 attachable/detachable to/from the image forming device main body is smoothly executed, and vibration or the like is minimized, so that the problem of the transfer deviation or the like is solved.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image forming apparatus such as a copying machine or a printer employing an electrophotographic system.

[0002]

2. Description of the Related Art FIG. 6 shows an example of a conventional general copying machine.

FIG. 6 is a cross-sectional view of a conventional copying machine. In a lower half portion of an apparatus main body 106 of the copying machine, a sheet feeding cassette 11 having a plurality of sheet materials 103 stacked therein is stacked.
The sheet material 103 accommodated in each of the sheet cassettes 18 is provided with a sheet feeding roller 119.
a, 119b, 119c, and a transport roller 120 to a resist roller 122 via a transport path 121.

The sheet material 103 conveyed to the registration roller 112 is conveyed substantially horizontally (in the direction of arrow b in FIG. 2) from the right to the left in FIG. And a transfer separation charger that is disposed in the vicinity of the photosensitive drum 101 (downward in the figure), which is rotating in the direction of arrow g in the figure. 102 and between. Then, the sheet material 103 starts to contact the photosensitive drum 101 in the transfer area a, and the photosensitive drum 10
1 is transferred. The photosensitive drum 10
The untransferred toner left on 1 is stored in cleaner 112.

[0005] The sheet material 103 is provided on the photosensitive drum 1.
With the rotation of No. 01, the paper passes through the transfer area a and is sent in the direction of arrow b in the figure. A sheet conveying device 136 including a conveying belt 108 and a suction fan 109, which are wound around a driving roller 104 and a driven roller 105 and driven in the direction of arrow b, is disposed downstream of the feeding direction.

The sheet material 103 sent out from the transfer area a moves on the conveyor belt 108 with the suction fan 109.
The fixing inlet guide 123
Along the nip d of the fixing device 125 including the fixing roller 110 and the pressure roller 111, where the toner image is fixed.

When such copying machines are classified, for example, by unit, an image forming unit including a cleaner 112 and a photosensitive drum 101, and a fixing and conveying unit 1 from a registration roller 122 to a fixing device 125 via a conveying unit.
26 (of course, there are many other units when viewed from the entire image forming apparatus).

The rollers provided in the unit are transmitted with driving force from a motor (not shown) provided in the image forming apparatus main body 106 via gears, belts, and couplings. Alternatively, each roller is driven by mounting an individual motor dedicated to the unit on each unit. in this case,
The motor is mounted on the unit side or the image forming apparatus main body 106 side.

[0009]

However, the conventional image forming apparatus has the following problems.

For example, when a dedicated motor for a fixing device is provided in a fixing device provided in a fixing / conveying unit provided detachably, a large torque is required to rotationally drive the fixing device. Even if the fixing / conveying unit is mounted on the image forming apparatus by the positioning means, if various vibrations from the motor are large, the entire unit will vibrate, and image blurring which cannot be ignored in image formation will occur. was there.

When the fixing device dedicated motor of the fixing device provided in the fixing / conveying unit provided detachably is attached to the main body of the image forming device, a slight error due to a dimensional error of the image forming device and the fixing / conveying unit. Misalignment occurs. Conventionally, in order to avoid this misalignment, the misalignment has been absorbed by means of a coupling or the like which is rotated by receiving a driving force transmitted from a motor. In some cases, image blurring may occur, and the image may not be in line with the recent trend toward higher image quality.

Conventionally, a flywheel or the like is mounted on a fixing roller or the like in order to prevent an image shift occurring due to the above-mentioned reason. However, due to the flywheel or the like, extra load and inertia force are generated on each transmission gear. However, it was necessary to use metal gears instead of resin gears.

In the case where a fixing device dedicated motor is provided in a fixing device provided in a fixing / conveying unit provided detachably, an electric connector between the main body of the image forming apparatus and the fixing / conveying unit includes an electric supply cord and Since the number of signal lines and the like increases and the number of pins increases accordingly, a large connector is required, which deviates from the idea of compact image forming apparatuses in recent years.

When a motor dedicated to the fixing device of the fixing device provided in the fixing / conveying unit provided detachably is attached to the main body of the image forming device, a slight error due to a dimensional error of the image forming device and the fixing / conveying unit. Misalignment occurs. In order to avoid this misalignment, the position of the input gear provided in the fixing / conveying unit and the position of the gear transmitted and output from the motor attached to the image forming apparatus main body are assembled using a jig in pursuit of precision. However, increasing the number of man-hours during factory assembly was a problem. Further, if any trouble occurs in the market, and if this fixing / conveying unit is replaced by a service person, its position cannot be adjusted, thereby causing vibration and image displacement.

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and its object is to improve the transfer error of an image with a very simple configuration, to reduce the size of the apparatus body,
An object of the present invention is to provide an image forming apparatus capable of satisfying all of cost reduction, improvement of serviceability, and the like with a simple configuration.

[0016]

In order to achieve the above object, according to the first aspect of the present invention, a driving force from a driving source provided in an image forming apparatus main body is provided so as to be insertable into and removable from the image forming apparatus main body. An image forming apparatus that transmits power to the unit via a power transmission unit, wherein the drive source is configured to be movable in accordance with the position of the unit each time the unit is mounted on the image forming apparatus main body.

According to a second aspect of the present invention, in the first aspect of the invention, the driving source is constituted by a motor, and a positioning member is provided on one of a motor support plate or the unit to which the motor is attached, and the other is provided. A fitting hole is formed in the hole.

According to a third aspect of the present invention, in the second aspect of the present invention, the motor is supported by the motor support plate via an elastic member.

According to a fourth aspect of the present invention, in the second or third aspect, the power transmission means is constituted by a gear,
2.2 the motor or motor support plate as a gear module
It is characterized by being movable up to five times.

According to a fifth aspect of the present invention, in the first aspect, a positioning member is provided on one of the unit and the image forming apparatus main body, and a fitting hole is formed on the other.

According to a sixth aspect of the present invention, in the fifth aspect of the invention, the driving source is supported by an image forming apparatus main body via an elastic member.

According to a seventh aspect of the present invention, in the second or fifth aspect, the positioning member also serves as an input gear shaft or an output gear shaft.

According to an eighth aspect of the present invention, in the second, fifth or seventh aspect of the present invention, a pressure angle at which a tangential force acts on a unit-side input gear which is removably provided to the output gear. Wherein the positioning member is provided in the direction of.

According to a ninth aspect of the present invention, in the third or sixth aspect, the hardness of the elastic member below the image forming apparatus main body is set higher than that of the elastic member above the image forming apparatus main body. It is characterized by the following.

According to the invention described in claim 1, 2, or 5,
Power is smoothly transferred to a unit that can be inserted into and removed from the image forming apparatus main body, vibrations and the like are minimized, and problems such as transfer deviation are solved.

According to the third, fourth or sixth aspect of the present invention,
The movement of the motor or the motor support plate becomes possible, and since this movement amount is 2.25 times that of the gear module, it is possible to correct the shift amount corresponding to the height of the gear teeth, which occurs when the movement occurs. Backlash is also absorbed.

According to the seventh aspect of the present invention, since the positioning member also serves as the shaft of the input gear or the shaft of the output gear, the size and cost of the image forming apparatus main body can be reduced.

According to the eighth aspect of the present invention, since the positioning member is provided in the direction of the pressure angle at which the tangential force acts on the input gear on the unit side, the vibration generated from the motor or the like is further reduced, and the image quality is improved. The level is raised.

According to the ninth aspect, the hardness of the elastic member on the lower side of the main body of the image forming apparatus is set higher than that of the elastic member on the upper side of the main body of the image forming apparatus. Falling to is prevented.

[0030]

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

FIG. 1 is a perspective view showing the structure of a drive transmission system of the image forming apparatus according to the present invention, and FIG. 2 is a perspective view of FIG. Since the basic configuration of the image forming apparatus according to the present invention is the same as that shown in FIG. 6, in the following description, the same elements as those shown in FIG.

In FIG. 6, a transfer area a composed of a photosensitive drum 101 and a transfer separation charger 102 and a fixing device 1
A sheet material conveying device 136 is disposed between the fixing roller 110 and the nip d of the pressure roller 111.
The sheet conveying device 136 includes a conveying belt 108 and a driving roller 104 as a driving unit of the conveying belt 108.
Roller 105 and conveyor belt 1 as driven means
A suction fan 109 is provided as air suction means for suctioning the sheet material 103 passing over the area 08.

The driving roller 104 for driving the transport belt 108 is disposed on the downstream side in the sheet transport direction and is driven to rotate, and the driven roller 105 is rotatably supported.

The suction fan 1 is provided inside the conveyor belt 108.
The suction fan 109 sucks the sheet material 103 on the transport belt 108 to the transport belt 108.

In the transfer area a, the photosensitive drum 1
The sheet material 103 onto which the toner image on the sheet No. 01 has been transferred is rotated as shown in FIG.
, And is attracted to the conveyor belt 108 by the action of the suction fan 109, so that the conveyor belt 1
08. Here, the conveyance belt 108 is a motor 137 already attached to the image forming apparatus main body 106.
Since the sheet material 103 is rotated by transmitting the driving force from the sheet material 103 (see FIG. 2), the sheet material 103 is conveyed in contact with the conveyance belt 108. After that, the sheet material 103 is conveyed on the conveyance belt 108, and its front edges are fixed along the fixing entrance guide 123 by the fixing roller 110 and the pressure roller 11 of the fixing device 125.
1 and is conveyed by the rotational force of the fixing roller 110 and the pressing roller 111,
8 discharges the image forming apparatus main body 106.

In the event that the conveyance failure of the sheet material 103 occurs in the fixing / conveying unit 126, since the entire fixing / conveying unit 126 is configured to be able to be inserted into and removed from the image forming apparatus main body 106, the conveyance failure occurs. The processing of the sheet material 103 is easily performed.

In the above configuration, the fixing roller 110, the driving roller 104, and the paper discharging roller 138 are connected to a dedicated motor 137 (FIG. 2) attached to the main body 106 of the image forming apparatus.
).

As shown in FIG. 2, the dedicated motor 137 is fixed to a motor support plate 139 with screws 140.
This motor support plate 139 is a rear plate 141 of the image forming apparatus main body.
Are fixed by screws 140 via an elastic member 142. The elastic member 142 is preferably made of a rubber-based material having a vibration absorbing and vibration damping effect.

As shown in FIG. 1, the motor support plate 139 has a circular hole 1 into which a pin 143 as a positioning member provided in the fixing and conveying unit 126 is fitted.
44 are formed. The dedicated motor 13 is provided in the vicinity of the motor support plate 139 where the circular hole 144 is formed.
7 is penetrated, and a drive gear 145 for driving output is attached to an end of the output shaft 146.

On the other hand, a drive input gear (idler gear) 1 is attached to the positioning pin 143 of the fixing and conveying unit 126.
A driving force is distributed to the fixing roller 110, the transport belt driving roller 104, the paper discharge roller 138, and the like via the gear 147.

After the fixing / conveying unit 126 is pulled out,
When this is mounted on the image forming apparatus main body 106 again,
Pin 1 for positioning the fixing and conveying unit 126
43 is a circular hole 1 for fitting provided in the motor support plate 139.
44.

The motor support plate 139 is connected to the fixing conveyance unit 12.
6 is slidably moved along the rear side plate 141 of the image forming apparatus main body in accordance with the positioning pins 143 of FIG.
m or less). At this time, the amount of movement of the output shaft or the input shaft in the normal direction is 2.2 in the module of the gears 145 and 147.
By lowering the hardness of the elastic member 142 so that the elastic member 142 can move up to five times, it is possible to avoid the tooth bottom contact between the gears 145 and 147.

The movement of the motor support plate 139 due to the equalization is absorbed by the elastic deformation of the elastic member 142.

As shown in FIG. 3A, the elastic member 142 is inserted into a circular hole formed in the motor support plate 139 and the rear plate 141 of the main body of the image forming apparatus. 140 is screwed and inserted. A nut 142n is screwed into the end of the screw 140, and if the screw 140 is turned from the state shown in FIG. 3A, the nut 142n moves along the screw 140, as shown in FIG. Since the elastic member 142 expands as described above, the motor support plate 139 is elastically tightened and supported by the rear plate 141 of the image forming apparatus main body.

Here, the hardness of the elastic member 142 on the lower side of the image forming apparatus main body is determined by the elastic member 1 on the upper side of the image forming apparatus main body.
If it is higher than 42, the motor 137 or the motor support plate 139 will not fall or tilt.

The fixing transport unit positioning pin 143 is connected to the fitting circular hole 1 formed in the motor support plate 139.
When the motor support plate 139 is equalized by being fitted to the motor support plate 139, the motor support plate 139 is provided on the output gear 145 attached to the output shaft 146 of the motor 137 fixed to the motor support plate 139 by screws 140 and the fixing and conveying unit 126. Input gear 1 rotatably mounted on positioning pin 143
47 is optimally positioned and power is smoothly transmitted.

The input gear 147 is constantly biased toward the output gear 145 by biasing means (not shown).
For this reason, even if the peaks of the output gear 145 and the input gear 147 hit each other and they do not mesh well, the input gear 14
7 when the output gear 145 is rotated by a minute,
45 and 147 mesh well. At this time, the amount of movement of the output shaft or the input shaft in the direction of the normal is the gear 145, 147.
The gear 145, 147 can be prevented from contacting the bottom of the gear by making it movable up to 2.25 times of the module.

The direction of the pressure angle at which the tangential force acts by engaging with the input gear 147 on the side of the fixing and conveying unit 126 provided so as to be insertable into and removable from the output gear 145 transmitting the driving force from the motor 137 (see FIG. 4). The pressure angle in this case is 20
°) includes the motor 137 or the motor support plate 139.
Fixing transport unit positioning pin 1 for preventing
43 are arranged.

The present embodiment can be applied to a unit in which an image shift may occur due to rotational driving of the cleaner 112, the photosensitive drum 101, the developing container, and the like. When individual motors are provided for each unit, all motors can be made the same.

In this embodiment, the elastic member 1
As for 42, the motor support plate 139 is elastically supported by using a material mainly made of rubber, but a long screw 140 shown in FIG.
L on the rear plate 141 of the main body of the image forming apparatus, and the spring 1 between the motor support plate 139 and the head 140H of the screw 140L.
If a structure is adopted in which the motor support plate 139 is supported by contracting the motor support plate 139, the movement by the equalization becomes smooth, and there is no worry about the motor support plate 139 falling off.

The dedicated motor 137 is connected to the motor support plate 139.
It is also possible to fix the motor support plate 139 to the rear plate 141 of the image forming apparatus main body with the screw 140 via an elastic member 142 via a screw 140.

[0052]

As is apparent from the above description, according to the present invention, the driving force from the driving source provided in the image forming apparatus main body is supplied to the unit provided in the image forming apparatus main body so as to be insertable and removable. In the image forming apparatus that transmits the image data through the transmission unit, the drive source is configured to be movable in accordance with the position of the unit each time the unit is mounted on the image forming apparatus main body. In addition, it is possible to obtain an effect that all of the image forming apparatus main body such as downsizing, cost reduction, and serviceability can be satisfied with a simple configuration.

[Brief description of the drawings]

FIG. 1 is a perspective view illustrating a configuration of a drive transmission system of an image forming apparatus according to the present invention.

FIG. 2 is a perspective view of FIG. 1 as viewed from the rear.

FIG. 3 is a cross-sectional view showing a mounting structure of a motor support plate to a rear side plate of the image forming apparatus main body.

FIG. 4 is a diagram illustrating a meshing state of an output gear and an input gear.

FIG. 5 is a cross-sectional view showing a structure for attaching a motor support plate to a rear side plate of the image forming apparatus main body.

FIG. 6 is a sectional view of a conventional image forming apparatus.

[Explanation of symbols]

 106 Image forming apparatus 126 Fixing / conveying unit (unit) 137 Motor (drive source) 139 Motor support plate 140 Screw 142 Elastic member 143 Positioning pin (positioning member) 144 Circular hole (fitting hole)

Claims (9)

[Claims] 1. An image forming apparatus for transmitting a driving force from a driving source provided in an image forming apparatus main body to a unit removably provided in the image forming apparatus main body via a power transmitting means, wherein the driving source is An image forming apparatus, wherein the unit is configured to be movable in accordance with the position of the unit each time the unit is mounted on the image forming apparatus main body. 2. The apparatus according to claim 1, wherein the drive source is a motor, and a positioning member is provided on one of the motor support plate or the unit to which the motor is mounted, and a fitting hole is formed on the other. 2. The image forming apparatus according to 1. 3. The image forming apparatus according to claim 2, wherein said motor is supported by said motor support plate via an elastic member. 4. An image forming apparatus according to claim 2, wherein said power transmission means is constituted by a gear, and said motor or said motor supporting plate is movable up to 2.25 times a module of said gear. . 5. The image forming apparatus according to claim 1, wherein a positioning member is provided on one of the unit and the main body of the image forming apparatus, and a fitting hole is formed on the other. 6. The image forming apparatus according to claim 5, wherein said driving source is supported by an image forming apparatus main body via an elastic member. 7. The image forming apparatus according to claim 2, wherein the positioning member also serves as an input gear shaft or an output gear shaft. 8. The positioning member is provided in a direction of a pressure angle at which a tangential force acts on an input gear of a unit which is provided so as to be insertable into and removable from the output gear. , 5 or 7. 9. The image forming apparatus according to claim 3, wherein the hardness of the elastic member below the image forming apparatus main body is set higher than that of the elastic member above the image forming apparatus main body.