JPH0367829A - Conveyance device - Google Patents

Abstract

PURPOSE:To automatically correct the widthwise positional deviation of a transfer belt by providing an eccentric roller rotatably following the transfer belt deviated positionally widthwise in the rotation under the condition of rotating coaxially with and independently of a rotatable member, while providing a means for increasing an urging force of an urging means in accordance with the rotation of the eccentric roller. CONSTITUTION:When a transfer belt 30 is positionally widthwise deviated during the rotation of a rotatable member 27, an eccentric roller 40 rotatably follows the transfer belt 30. Then, an urging means (compression spring) 39 urges the end of the rotatable member 27 at the rotating eccentric roller 40 side in the direction of increasing the tension of the transfer belt 30, so that the positional deviation of the transfer belt 30 is corrected.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a conveyance device suitable for use in a transfer paper conveyance system of a copying machine, a printer, or the like.

(Conventional technology) A conventional conveying device of this type is shown in FIGS. 10 to 13.

In FIGS. 1O and 11, 100 is an endless conveyor belt, and this conveyor belt 100 is connected to a driving roller 101.
, is stretched around the driven roller 102. Followed roller 10
Both ends of the rotation shaft 103 of No. 2 are inserted into guide holes 105 of side plates 104 arranged on both sides of the conveyor belt 100. Further, the rotating shaft 103 includes solenoids 106a and 1.
A spring 107 connected to the conveyor belt 100 is locked, and this spring 107 is attached to the rotating shaft 1 in the direction of pulling the conveyor belt 100.
03 has an equal 6-tension elastic force on both ends. On the other hand, the rotation shaft 108 of the drive roller 101 is held at a predetermined position by a bearing (not shown) on the side plate 104. In addition, 109a and 109b are between the side plates 104,
Conveyor belt 1. This is a detection means provided along the width direction of OO.

In the above configuration, when the drive roller lO1 is rotated in the direction of the arrow by a motor (not shown), the conveyor belt 100 also rotates in the direction of the arrow, and the object placed on the conveyor belt lOO is conveyed. During conveyance, if the conveyor belt lOO is misaligned, for example in the direction B in the figure, the detection means 109a
detects this and sends a signal to a control circuit (not shown), turning on the solenoid 109a and pulling the spring 107 in the direction of arrow A, so that the lower end of the driven roller 102 in the figure is stronger than the upper end. The conveyor belt lOO is in a tensioned state. As a result, the conveyor belt lOO gradually moves in the downward direction in the figure, and the positional deviation is corrected.

In addition, what is shown in FIGS. 12 and 13 is a conveyor belt N
0(l) in the width direction of the guide roller 110a.

110b is provided. This guide roller 110a
, 110b are held by a vertical rotation axis 111. Note that the end of the rotating shaft 103 of the driven roller 102 is
The difference from FIGS. 1O and 11 is that, like the drive roller 101, it is held at a predetermined position relative to the side plate 104.

In the case shown in FIGS. 12 and 13, when a positional shift occurs in the width direction during the rotation of the conveyor belt lOO, the conveyor belt 10
0 side edge 100a is the guide roller 110a (or 110
b), and the guide roller 11Oa (or 110b) applies a reaction force in the straightening direction to the conveyor belt).
100 positional deviations are corrected.

(Problems to be Solved by the Invention) However, the above conventional example has the following drawbacks.

■ In the conveying device shown in FIGS. 10 and 11, the detection means 109a, 109b and the solenoids 106a, 106
b. Furthermore, a control circuit (not shown) is required to operate these, which not only complicates the structure but also increases manufacturing costs.

■ Similarly, in the conveyance device shown in Figs. 10 and 11,
Mechanical noise is generated every time the solenoids 106a and 106b operate, which is undesirable.

12 and 13, the conveyor belt 100 comes into sliding contact with the guide roller 110a or 110b every time the conveyor belt 100 is misaligned, so it is easily worn out and the life of the conveyor belt lOO is shortened.

■ When sliding on the guide rollers 110a and 110b, the side edge 100a of the conveyor belt (100) is wavy, so the conveyor belt (conveyor belt)
Conveyance defects such as misalignment or falling off of the conveyed object on the conveyance sheet 100 occur.

The present invention has been made to solve the above-mentioned problems, and it is an object of the present invention to provide a conveying device equipped with a conveyor belt misalignment correcting mechanism that has a simple structure, is free from mechanical noise, and can be manufactured at low cost.

Another object of the present invention is to provide a conveying device that not only maintains the durability of the conveyor belt but also prevents conveyance defects due to waving of the side edges.

(Means for Solving the Problems) In order to achieve the above object, the present invention provides a conveying device having two endless conveyor belts and a rotating member on which the conveyor belt is stretched, in which at least one side edge of the conveyor belt is fixed. A biasing means for biasing the end of the rotating member in the direction in which the conveyor belt is stretched is provided on the outside of the rotary member, and an eccentric roller that rotates following the conveyor belt that shifts in position in the width direction during rotation is attached to the rotating member. The roller is coaxial with the rotating member and rotates separately from the rotating member, and is provided with means for increasing the urging force of the urging means in response to the rotation of the eccentric roller.

(Function) The function of the present invention based on the above configuration is that when the conveyor belt is displaced in the width direction while the rotating member is rotating, the eccentric roller rotates to follow the conveyor belt.

Then, the biasing means biases the end of the rotating member on the side where the eccentric roller rotates in a direction that increases the tension of the conveyor belt.

(Example) Next, the present invention will be explained based on the example shown in FIGS. 1 to 9.

FIG. 2 shows a schematic configuration of an image forming apparatus l to which the present invention is applied.

In the figure, reference numeral 2 denotes an apparatus main body, and above the apparatus main body 2, optical means such as a light source 39, reflection mirrors 4, 5, and 6, an optical lens 7, and reflection mirrors 8, 9, and 10 are arranged. 11
is a photosensitive drum provided approximately at the center of the main body 2 of the apparatus, and around this photosensitive drum 11 is a negative charger 12. Developing device 13
．． Pre-transfer charger 14. Image forming means such as a cleaner 15 is arranged.

Below the device main body 2, there is a power cellar) 1 that stores the transfer paper P.
6 is installed. 17 is a paper feed roller that carries out the transfer paper P from the cassette 16; 18° 19.20 is a conveyance path 21
This is a pair of conveyor rollers provided inside. In addition, 22 is a fixing device,
23 is a paper discharge section, and 24 is a re-conveyance path.

Reference numeral 25 denotes a conveying device provided below the photosensitive drum 11. This conveying device 25 includes a driving roller 26 and a driven roller (rotating member) 27 arranged parallel to each other, and a separate conveying device provided between the driving roller 26 and the driven roller 27. 28, 29, and an endless conveyor belt (30) stretched around the outer periphery of these loaves 26, 27, 28, 29. Note that a transfer roller 31 is provided with the conveyor belt 30 sandwiched between the photosensitive drum 11, and is connected to a high-voltage power source (not shown).

FIGS. 1 and 3 are detailed views of the conveying device 25. FIG. The conveyor belt 30 is made of a resin material such as polyester in order to be charged. Also, the drive roller 26
The rotating shaft 32 is held by bearings 34 on side plates 33 provided on both sides of the conveyor belt 30.

Both ends of the rotating shaft 35 of the driven roller 27 are held by bearings 37 movably mounted in a guide hole 36 provided in the side plate 33 so as to face the driving roller 26 . A slide member 38 is slidably provided in the guide hole 36 at a position closer to the drive roller 26 side. A compression spring 39 is interposed between the slide member 38 and the bearing 37, and biases the bearing 7 in the direction of arrow E with a predetermined force.
(conveyor bell stretched over the driving roller 26 and driven roller 27)
30 to maintain proper tension.

Reference numeral 40 denotes an eccentric roller having a protrusion 41 near the side plate 33. The eccentric roller 40 is assembled to the rotating shaft 35 in a loosely fitted manner, and is coaxial with the rotating member 27 and connected to the rotating member 27. It rotates separately. This eccentric roller 40 is provided outward (closer to the side plate 33) at a predetermined distance from the side edge 30a of the conveyor belt 30 in a fixed position. In addition, the rotating shaft 3
5 is provided with a fixture 42 as shown in FIG. 3, so that the eccentric roller 40 can be maintained in close proximity to the driven roller 26.

The guide hole 36 provided in the side plate 33 has an inner (
A bin 43 is provided protruding toward the transport belt 30 side), and a dogleg-shaped link 44 that swings about the bin 43 as a fulcrum is attached. A guide groove 45 is provided in one arm 44a of this link 44, and this guide groove 45
A bottle 46 protruding from the slide member 38 is inserted therein. Further, the other arm 47 of the link 44 is in contact with the outer peripheral surface of the eccentric roller 40 so as to straddle the rotating shaft 35 .

It goes without saying that the configuration shown in the first figure is also provided on the side plate 33 on the opposite side that sandwiches the conveyor belt 30 and the rotating shaft 35, as shown in FIG.

Next, the operation of the above embodiment will be explained.

First, when a copy button (not shown) of the image forming apparatus L is pressed, an original (not shown) is scanned by optical means, and the photosensitive drum 11 is exposed to reflected light H to form an electrostatic latent image. After being developed by the device 13, the photosensitive drum 11 is rotated in the direction of the arrow to move to the transfer position.

On the other hand, the transfer paper P in the cassette 18 is carried out by the paper feed roller 17 and reaches the transfer section via the conveyance path 21. This transfer paper P is transferred to the conveyor belt 3 in a timely manner.
It is placed on the transfer paper P and is electrostatically attracted by the charging of the transfer roller 31, and the development on the photosensitive drum 11 is transferred to the transfer paper P.
transferred on top. Thereafter, the transfer paper P, which is conveyed in the direction of arrow F in FIG. The paper will be discharged to the outside through the paper discharge section 23.

By the way, during the above operation, in the conveyance device 25, the drive roller 26 is rotated in the direction of the arrow F by a motor (not shown), and the conveyance belt 30 is rotated in the direction of the arrow F. As shown in FIG. 3, when the conveyor belt 30 is in a normal position contacting only the outer peripheral surface of the driven roller 27 (in a state where there is no positional deviation in the width direction), the protruding portion of the eccentric roller 40 41 is link 4 as shown in Figure 4.
It is not in contact with the arm 47 of No. 4. Therefore, a certain tension is ensured by the predetermined urging force (in the direction of arrow E) of the compression spring 39, and the driving roller 26 and the driven roller 27 are in a parallel state.

Furthermore, if a positional shift occurs in the width direction during the rotation of the conveyor belt 30, for example, a certain amount of shift in the direction of arrow G in FIG. It will be in a state where it is on top of the surface. Then, eccentric roller 40
As shown in FIG. 5, the link rotates in the direction of the arrow following the conveyor belt 30, and the protrusion 41 contacts the arm 47, causing the link 44 to rotate around the pin 43 in the direction of the arrow and return. Performs periodic operation. Therefore, the pin 46 moves to the right in the drawing by the guide groove 45 of the arm 44a,
The slide member 38 slides in the direction of arrow J. the result,
The end of the rotating shaft 35 (only the upper end in FIG. 3) is urged more strongly in the direction of the arrow by the elastic force of the compression spring 39, increasing the tension of the conveyor belt 30.

On the other hand, the eccentric roller 40 on the opposite side (lower side in FIG. 3) is still in a stationary state, and the biasing force against the end of the one-rotation shaft 35 remains unchanged. Therefore, the conveyor belt 30 gradually moves in the width direction from the side with higher tension to the side with lower tension, and the driven roller 2
It returns to the normal tensioning position where it contacts only the outer circumferential surface of 7. In this state, both eccentric rollers 40 provided on the rotating shaft 35 do not rotate.

Further, even when the conveyor belt 30 is displaced downward in FIG. 3, it is returned to its original position by the same action as described above.

The positional deviation correction operation of the conveyor belt 30 is performed by eccentric rollers 4
0. Link 44. Since it is mechanically controlled by the slide member 38, etc., there is no need for a special control circuit that is required when conventional solenoids, detection means, etc. are used, and the structure is simple and can be manufactured at low cost. There is no noise at times. Also, as in the past,
Since there is no regulating member that comes into sliding contact with the side edge 30a of the conveyor belt 30, there is no wear on the conveyor belt 30 due to contact, and the conveyor belt 30 is wavy and the transfer material P is not displaced or falls off. Therefore, transfer defects will not occur.

FIG. 6 shows another embodiment.

A bracket 48 is provided on the surface of the side plate 33 on the conveyor belt 30 side.
There is a leaf spring 50 fixed to , and this leaf spring 50 moves the driven roller 27 in the direction of arrow E by coming into contact with the eccentric roller 40.
(Figure 7). When the conveyor belt 30 is displaced in the same manner as described above, the eccentric roller 40 follows and rotates as shown in FIG. ) 30 becomes stronger, one end side of the driven roller 27 is more strongly biased. As a result, the conveyor belt 30 gradually moves from the high tension side to the low tension side L, and returns to its normal state.

In this embodiment as well, it is needless to say that biasing means having the same configuration are installed on the side plates 33 on both sides sandwiching the conveyor belt 30.

FIG. 9 shows yet another embodiment.

In this embodiment, one side plate 33 (upper side in the drawing)
Links 44 similar to FIG. 1 only on the sides. Eccentric roller 40. A slide member 38 and the like are provided, and only a compression spring 39a is provided on the other side. Further, one end of the compression spring 39a is directly fixed to the side plate 33, and the guide hole (not particularly shown) is also short. Furthermore, the compression spring 39a is set to have a larger elastic force than the other compression spring 39.

Therefore, in this embodiment, the conveyor belt 30 rotating in the F direction always tends to be displaced in the arrow G direction. And eccentric roller 40. Link 44, slide member 3
8 etc. act in the same manner as described above, and are returned to their normal positions and try to shift their positions again. In this way, the conveyor belt 30 rotates while repeatedly shifting and returning.

(Effects of the Invention) Since the present invention is constructed as described above, it is possible to automatically correct misalignment of the conveyor belt in the width direction by only mechanical operation. Therefore, there is no need for a special control circuit such as a conventional conveying device using a solenoid, a detection means, etc., the structure is simple, it can be manufactured at low cost, and no noise is generated during operation. In addition, unlike in the past, there is no regulating member that slides into contact with the side edges of the conveyor belt, so there is no wear on the conveyor belt due to contact, and there is no risk of the conveyor belt waving, causing the conveyed object to shift its position or fall off. It has various effects such as:

[Brief explanation of drawings]

1 to 9 show embodiments of the present invention, FIG. 1 is a perspective view of the first embodiment, FIG. 2 is a schematic front sectional view of an image forming apparatus to which the invention is applied, and FIG. 3 is a perspective view of the first embodiment. A plan view of the first embodiment, FIGS. 4 and 5 are explanatory diagrams showing the operation of the first embodiment, FIG. 6 is a perspective view of the second embodiment, and FIGS. 7 and 8 are illustrations of the second embodiment. 9 is a plan view showing the third embodiment; FIGS. 10 and 11 are plan views and front views showing the first conventional example; FIGS. 12 and 13 The figures are a plan view and a front view showing a second conventional example. Explanation of symbols 25... Conveying device 27... Followed roller (rotating member) 30... Conveying belt 30a... Side edge of the conveying belt 39... Compression spring (biasing means) 40... Eccentricity Colo 6 Figure 1 Figure 4 Jυ Figure 10 Figure 11 Figure 12 Z (/4 IC) lj 10a 11 03 Figure 13

Claims (1)

[Claims] In a conveying device having an endless conveyor belt and a rotating member on which the conveyor belt is stretched, an end of the rotating member is attached to the outside of at least one side edge of the conveyor belt in the direction in which the conveyor belt is stretched. In addition, an eccentric roller is provided coaxially with the rotating member and rotates separately from the rotating member, and the eccentric roller is coaxial with the rotating member and rotates separately from the rotating member. A conveying device characterized by being provided with means for increasing the urging force of the urging means in response to rotation.