JPH04144849A - Supporting device of endless belt - Google Patents

Abstract

PURPOSE:To always keep the attitude of a specified part of an endless belt constant and positively adjust the alignment by providing an attitude supporting device for the belt, which presses the internal peripheral surface of the endless belt in the whole area in the width direction, near rolls provided with an alignment adjusting device. CONSTITUTION:A belt supporting device 3 rotating an endless belt while supporting it comprises a drive roll 3a and tension roll 3b arranged spacedly with each other and an alignment adjusting device displacing the roll 3b and an endless belt attitude supporting device comprising rotary rolls 31a and 31b arranged on the internal periphery of the belt 1 near the rolls 3a and 3b. The belt 1 is fitted around the rolls 3a, 3b, 31a and 31b, and the carrying surface of a recording sheet S is supported flat by the rotary rolls 31a and 31b. In the next step, the rolls 31a and 31b as an endless belt attitude supporting device press against the internal peripheral surface of the belt 1 in the whole area in the width direction being pivotally supported by the frame body of the device.

Description

Detailed Description of the Invention [Field of Industrial Application] The present invention relates to a support device for an endless belt that carries and conveys a conveyed material such as paper, cloth, film, or an electrostatic latent image, and particularly relates to an endless belt support device that supports and conveys a conveyed material such as paper, cloth, film, or an electrostatic latent image. The present invention relates to a support device for an endless belt that requires strict flatness on the recording sheet conveyance surface.

(Prior Art) Conventionally, this type of endless belt support device has been used, for example, as a photoreceptor belt that carries and conveys an electrostatic latent image in a multicolor image recording device such as a copying machine or a printer, or as a photoreceptor belt that carries and conveys an electrostatic latent image. It is used as an endless belt to transport recording sheets on which images are recorded.

As shown in FIG. 3, such a multicolor image recording apparatus, for example, a multicolor image recording apparatus having an endless belt for conveying a recording sheet on which an image is to be recorded, has a recording sheet supply section 4 and a recording sheet feeding section 4. A discharge section 7, an endless belt 1 that forms a conveyance path for the recording sheet S between them, and toner images (possible) of four colors (cyan, magenta, yellow, and black) arranged along the endless belt 1. 4 sets of visible image forming units) 2a, 2b forming a visual image)
, 2c, 2d, etc. are the main parts.

The visible image forming units 2a, 2b, 2c, and 2d each include a photoreceptor drum 21, which is an electrostatic latent image carrier, and
A charger 22, an exposure device 23 which is an electrostatic latent image writing means,
It includes a developing device 24, a transfer device 25, and a cleaner 26, and sequentially transfers toner images corresponding to image information of each color onto the recording sheet S conveyed by the endless belt 1 in multiple layers. Furthermore, the endless belt l is an endless belt that has flatness under a predetermined tension.
For example, a belt made of rubber or resin having a predetermined elasticity, or a metal belt whose surface is coated is used, and the endless belts 1 are arranged at a predetermined distance from each other in order to convey the recording sheets S. It is supported by an endless belt support device consisting of a pair of rolls and the like.

This endless belt support device consists of a pair of rolls 3a
, 3b, alignment adjustment means (not shown), etc., and when the endless belt moves, the downstream roll 3a is used as a drive roll, and the upstream roll 3b is used as a tension roll. The drive roll 3a is arranged to advance the endless belt 1 at a constant speed, and is, for example, a substantially cylindrical roll rotated by a servo motor, and the tension roll 3b applies a predetermined tension to the endless belt 1. For example, it is a substantially cylindrical roll having a predetermined pressure spring and a driven roll without driving force. In addition, an alignment adjusting means (not shown) is for correcting the misalignment of the endless belt 1 by vertically swinging (displacing) the rotating shaft of the roll with respect to the initial setting position, and is used to correct the misalignment of the endless belt 1. It may be disposed on one or both of them, such as the photoreceptor belt drive mechanism of our copying machine FX-9200.

Note that the roll 4b provided in the multicolor image recording apparatus described above is a supply roll that supplies the recording sheet S, the tacking roll 5 is for adsorbing the recording sheet S to the endless belt 1, and the cleaner 8 is for supplying the recording sheet S. It is for removing paper dust and toner adhering to the outer peripheral surface of the belt 1, and the rolls 3c and 3d are driven rolls without driving force.

However, in such a multicolor image recording apparatus, when the endless belt 1 shifts, the alignment adjusting means displaces the rolls 3a and 1 or 3b, thereby returning it to its original position. and the displacement of l or 3b is the displacement of these rolls 3a, 3b
This is a cause of impairing the flatness of the endless belt 1 that is stretched between them. When the flatness of the endless belt 1 is impaired, the visible image forming units 2a, 2b, 2c disposed along the endless belt 1,
There has been a problem in that the distance between each of the belts 2d and the endless belt 1 changes, resulting in unevenness between the distances, resulting in color shifts and transfer omissions in multicolor images.

This limits the degree of displacement of the rolls 3a and l or 3b by the alignment adjusting means, and as a result, it is difficult to quickly and effectively correct the deviation of the endless belt 1 by the alignment adjusting means. The problem was that it was difficult.

[Problems to be Solved by the Invention] Therefore, as a result of intensive research in order to solve such problems, the present inventors have found that, in an endless belt support device, an alignment adjusting means is provided near the roll. By providing an endless belt posture holding means that presses almost the entire width direction of the inner circumferential surface of the endless belt to eliminate the roll effect caused by roll displacement, a predetermined portion of the endless belt is always kept in a constant posture (flat surface). ), and furthermore, it was discovered that the alignment adjustment of the endless belt could be performed quickly and effectively, and the present invention was completed.

That is, an object of the present invention is to provide an endless belt posture holding means in an endless belt support device, thereby ensuring flatness in the portion where flatness of the endless belt is required, and furthermore, making it possible to adjust the alignment of the endless belt. The aim is to actively carry out the following.

(Means for Solving the Problems) That is, the present invention spans an endless belt between a pair of rolls arranged at a predetermined distance from each other, and one or both of the pair of rolls is provided with an alignment belt. In an endless belt support device that is provided with an adjustment means and is capable of correcting deviation of the endless belt by displacing the roll by the alignment adjustment means, the inner periphery of the endless belt is located near the roll on which the alignment adjustment means is provided. The present invention is characterized in that an endless belt posture holding means is provided which presses substantially the entire widthwise area of the belt surface to eliminate the influence of displacement of the rolls.

Here, as the endless belt posture holding means, any means may be used as long as it is in pressure contact with the inner circumferential surface of the endless belt over substantially the entire width direction and eliminates the influence of displacement of the rolls. It may be a metal plate or a metal rod that has low frictional resistance with the circumferential surface, or a rotating roll with a small diameter that rotates while being pressed against the inner circumferential surface of the endless belt. Furthermore, these endless belt posture holding means may have a pressing spring so as to press against the inner circumferential surface of the endless belt with a constant urging force.

Therefore, the endless belt posture holding means is installed at both upstream and downstream ends in the belt movement direction of a region where flatness is required for the endless belt. Furthermore, when there is a material to be transported on this endless belt, it is preferable to have a position where the material to be transported is supported on the endless belt, and a device in which the material to be transported is constituted by the endless belt. In addition, when this endless belt posture holding means is provided on either the upstream side or the downstream side in the belt movement direction, a roll that does not have a complete alignment adjustment means is provided with a function substantially similar to that of the alignment adjustment means. By doing so, it is of course possible to obtain the same effect as when both of the rolls are provided with alignment adjusting means.

Furthermore, when the endless belt support device according to the present invention is used as a sheet conveying device for conveying a conveyed material,
The rotating rolls, metal rods, etc. constituting the above-mentioned endless belt posture holding means are made of small diameter ones, and the endless belt is bent from the upstream side to the downstream side of the endless belt with the rotating rolls etc. as a boundary to bend the conveyed material. By applying pressure to the peeling point, the conveyed material can be peeled more reliably.

[Function] According to the present invention, an endless belt is spanned between a pair of rolls arranged at a predetermined distance from each other, and one or both of the pair of rolls is displaced to provide an endless belt. In an endless belt support device equipped with an alignment adjustment means for correcting the deviation of the belt, the alignment adjustment means is in pressure contact with the inner circumferential surface of the endless belt over almost the entire width direction in the vicinity of the roll provided with the alignment adjustment means to adjust the displacement of the roll. Since the endless belt posture holding means is provided to eliminate the influence of Since it is not applied to the required portion, corrections to the shifting of the endless belt can be made quickly and effectively.

[Examples] Hereinafter, the present invention will be specifically described based on examples shown in the accompanying drawings.

FIG. 1 shows a case where an endless belt support device according to an embodiment of the present invention is used in a multicolor image recording device such as a printer.

This multicolor image recording apparatus includes a recording sheet supply section 4, a recording sheet discharge section 7, an endless belt 1 that forms a conveyance path for a recording sheet S between these, and an endless belt that supports this endless belt 1. A supporting device 3, and four sets of visible image forming units (2a, 2b) that form toner images (visible images) of four colors (cyan, magenta, yellow, and black) arranged along the endless belt 1. ,2
The main parts are composed of c, 2d, etc.

Here, the endless belt supporting device 3 that supports and advances the endless belt l includes a drive roll 3a and a tension roll 3 disposed at a predetermined distance from each other.
b, an alignment adjustment device (not shown) for displacing this tension roll 3b, and these rolls 3a, 3b.
and an endless belt posture holding device consisting of rotating rolls 31a and 31b disposed on the inner periphery of the endless belt near the endless belt. ,
A conveying surface for conveying the recording sheet S, which is a material to be conveyed, is formed such that its flatness is maintained by rotating rolls 31a and 31b. The roll 3a is the same as the conventional drive roll 3a, and the roll 3b is the same as the conventional tension roll 3b.

In addition, the rotating rolls 31a and 31b serving as the endless belt posture holding device are pivotally supported by a device frame (not shown) and are in pressure contact with the inner circumferential surface of the endless belt 1 over substantially the entire width direction, This is a driven roll that does not affect the progress of the endless belt l. Moreover, the roll diameter is formed smaller than the roll diameter of the drive roll 3a.

Further, the set position of the rotary roll 31a is a position where the recording sheet S is in pressure contact with the inner circumferential surface at the position where it is supplied, and the set position of the rotary roll 31b is a set position on the inner circumferential surface at the position where the recording sheet S is peeled off. This is the position where it comes into pressure contact with the

Note that the endless belt 1 is bent by the rotating rolls 31a and 31b from the upstream side to the downstream side of the rotating rolls 31a and 31b, and further bent by the rotating rolls 31a and 31b.
A peeling claw 9 that assists in peeling off the recording sheet S is provided near the outer peripheral surface of the portion bent by b.

In the multicolor image recording apparatus configured as described above, the recording sheet S carried in from the supply tray 4a via the supply roll 4b is adsorbed onto the endless belt 1 by the tacking roll 5, and then is moved along the endless belt 1. Accordingly, toner images of each color are sequentially transferred from each visible image forming unit 2, and a multicolor toner image is supported. and,
The recording sheet S, on which the toner image has been transferred, is peeled off at the bent portion and is discharged onto the recording sheet discharge section 7 via the fixing device 6, thereby completing the formation of the multicolor recorded image.

Incidentally, the deviation caused by the movement of the endless belt 1 is eliminated by an alignment adjustment device that displaces the tension roll 3b, but the flatness of the endless belt 1 is impaired during this adjustment. However, even during this adjustment, the alignment adjustment device does not affect the part of the endless belt 1 between the rotating rolls 31a and 31b due to the rotating rolls 31a and 31b, which are means for maintaining the posture of the endless belt. Multicolor images without color shift can be formed.

Next, FIG. 2 shows a multicolor image recording apparatus equipped with an endless belt support device according to another embodiment,
Unlike the embodiment shown in FIG. 1 above, the drive roll 3a itself, which is not provided with an alignment adjustment device, also has the function of a belt posture holding device, and the rotation of the drive roll 3a and the tension roll 3b provided on the side The attitude of the endless belt 1 is maintained by the rolls 31b. Note that the alignment adjustment device is provided on the tension roll 3b as in the embodiment shown in FIG.

In this embodiment, unlike the embodiment shown in FIG. 1 above, the belt posture holding device is simplified, thereby achieving the object of the present invention and simplifying the device and reducing cost. It is something.

[Effect] According to the endless belt support device of the present invention, near the roll provided with the alignment adjustment means, the inner circumferential surface of the endless belt is pressed over almost the entire width direction, thereby eliminating the influence of roll displacement. By installing an endless belt posture holding device, a predetermined part of the endless belt can always be kept in a constant posture (flat), and furthermore, the alignment of the endless belt can be actively adjusted. A support device can be provided.

[Brief explanation of drawings]

FIG. 1 is an explanatory diagram showing an embodiment of the endless belt support device according to the present invention, FIG. 2 is an explanatory diagram showing another embodiment of the endless belt support device according to the present invention, and FIG. 3 is an explanatory diagram showing an embodiment of the endless belt support device according to the present invention. FIG. 2 is an explanatory diagram showing a conventional example of a support device. [Description of symbols] (1)...Endless belt (3a)...Drive roll (31)...Rotating roll (3b)...Tension roll (S)...Recording sheet

Claims (4)

[Claims] (1) An endless belt is spanned between a pair of rolls arranged at a predetermined distance from each other, and one or both of the pair of rolls is provided with alignment adjustment means, and the rolls are adjusted by the alignment adjustment means. In an endless belt support device that can correct the misalignment of an endless belt by displacement, near the roll on which the above-mentioned alignment adjustment means is provided, there is a roller that is in pressure contact with the inner circumferential surface of the endless belt over almost the entire width direction. A support device for an endless belt, characterized in that it is provided with an endless belt posture holding means that eliminates the influence of displacement. (2) The pair of rolls is a drive roll located upstream in the belt movement direction and a tension roll located downstream, and at least an alignment adjustment means and an endless belt posture holding means are provided on the tension roll side. The endless belt support device according to item 1. (3) Claim 1 or 2, wherein the endless belt posture maintaining means is constituted by a rotating roll having a roll diameter smaller than that of the pair of rolls on which the endless belt is stretched.
Endless belt support device as described in Section 1. (4) The endless belt posture holding means disposed on the tension roll side is composed of a rotating roll with a small diameter, and the endless belt is bent from the upstream side to the downstream side of the rotating roll. The endless belt support device according to claim 2.