JP4316726B2 - Endless belt and image forming apparatus - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an endless belt used in a photosensitive belt such as a laser beam printer, an intermediate transfer device, a transfer separation device, a charging device, and a fixing device, and more particularly to correction of the belt misalignment.
[0002]
[Prior art]
An endless photosensitive belt used in an electrophotographic apparatus is made of a plastic material having a small elongation. When this type of endless belt is wound around a roller and stretched, it is rotated due to a slight imbalance in tension, parallelism error between rollers that stretch the endless belt, and circumferential length differences on both sides of the endless belt. Deviation occurs.
[0003]
In order to correct such a deviation of the belt, the endless photosensitive belt is provided with meandering prevention ribs on both side edges of the inner surface, and the taper piece is a meandering prevention guide provided with the meandering prevention ribs positioned on the roller end faces. It is configured so as to correct the deviation by making contact with. This meandering prevention rib is configured by bonding an elastic rib base with a pressure-sensitive adhesive or by curing and molding room temperature curable silicone rubber into a rib shape.
[0004]
[Problems to be solved by the invention]
The meandering prevention rib formed by adhering the rib base with a pressure-sensitive adhesive is a rib base over time because the pressure-sensitive adhesive is viscoelastic when a pressing load in the roller axial direction is generated due to the deviation of the belt. May be displaced or peeled off. In addition, since the meandering prevention rib formed by curing and molding the room temperature curable silicone rubber has low wear resistance, if the deviation of the belt is large, the meandering prevention rib is heavily worn, and the wear powder enters between the belt surface and the roller. For this reason, there are problems that cracks occur in the belt, and wear powder aggregates, resulting in poor cleaning.
[0005]
One object of the present invention is to provide an endless belt provided with a meandering prevention rib having a large wear resistance and a deviation correction effect.
[0006]
Another object of the present invention is to provide an image forming apparatus provided with an endless belt having a large displacement correction effect.
[0007]
[Means for Solving the Problems]
The present invention provides an endless belt in which a meander-preventing rib base is formed by adhering a meander-preventing rib base with an adhesive to both side edges of the belt base, the meander-preventing rib base is made of heat vulcanized rubber, and the adhesive is wherein by forming a soft room temperature curing rubber than meandering prevention rib substrate, thereby improving the wear resistance with increasing the tear strength and tensile strength of the meandering prevention rib.
[0008]
An unevenness into which an adhesive enters the adhesive surface of the meandering prevention rib base is provided, and the unevenness makes the effect even more remarkable by forming the recess in an undercut.
[0009]
The endless belt is an endless belt used for any of a photosensitive belt, an intermediate transfer device, a transfer separation device, a charging device, and a fixing device.
Further, an endless belt is wound around the driving roller, the driven roller, and the tension roller. The tension roller is supported by a tension arm that is rotatably attached to a support point, and the tension arm is pulled by a tension spring. In the image forming apparatus that applies tension by pressing the tension roller against the endless belt,
The endless belt is the above-mentioned endless belt, and the tension arm is disposed at both ends of the driving roller and engages with the driving roller and a taper piece that is rotatably arranged with respect to the driving shaft of the driving roller. The meandering prevention rib is positioned on the outer side in the axial direction of the driving roller and is close to the taper piece. It is.
[0010]
DETAILED DESCRIPTION OF THE INVENTION
Embodiments of the present invention will be described with reference to the drawings.
[0011]
FIG. 1 is a side view showing an endless photosensitive belt and its surrounding components in the image forming apparatus. The endless photosensitive belt 1 is wound around a driving roller 2, a driven roller 3, and a tension roller 4.
[0012]
The tension roller 4 is supported by a tension arm 6 rotatably attached to a support point 5, and pulls the tension arm 6 with a tension spring 7 to press the tension roller 4 against the photosensitive belt 1 to give tension. The tension arm 6 is pulled back by a correction link 9 that is positioned at both ends of the drive roller 2 and engages with a taper piece 8 that is rotatably arranged with respect to the drive roller 2 and the drive shaft 2a. Try to reduce the tension.
[0013]
In the image formation, the endless photosensitive belt 1 stretched in this way is rotated in the direction of arrow Q, and the rotating endless photosensitive belt 1 is charged by a charger 10 and an electrostatic latent image is formed by exposure 11. Then, the developing device 12 develops the electrostatic latent image to form a toner image, and the toner image is transferred to the intermediate transfer drum 13. Residual toner remaining on the endless photosensitive belt 1 without being transferred is cleaned by a cleaner 14.
[0014]
FIG. 2 is a front view showing a winding structure of the endless photosensitive belt 1 around the driving roller 2 for belt deviation correction according to the present invention. The endless photosensitive belt 1 includes a photosensitive belt substrate 1a obtained by coating a photosensitive material on a sheet-like insulating substrate, and meandering prevention ribs 1b and 1c on both side edges of the inner surface (back surface) of the photosensitive belt substrate 1a. The meandering prevention ribs 1b and 1c are configured to be positioned on the outer side in the axial direction of the driving roller 2 around which the endless photosensitive belt 1 is wound, and are formed on the taper pieces 8 (8a and 8b) positioned at both ends of the driving roller 2. Keep close.
[0015]
When the endless photosensitive belt 1 is rotated by rotating the driving roller 2 around which the endless photosensitive belt 1 is wound, if the endless photosensitive belt 1 is shifted in either the left or right direction, the side edge on the opposite side to the offset direction is detected. The meandering prevention rib 1b (1c) of the tape contacts the taper piece 8a (8b), and the taper piece 8a (8b) in contact with the endless photosensitive belt 1 is rotated in the same direction. When the taper piece 8a (8b) rotates, the tension roller 4 is displaced by pulling the correction link 9a (9b) engaged with the taper piece 8a, (8b), and is opposite to the offset direction of the endless photosensitive belt 1. By easing the belt tension on the side, the offset of the endless photosensitive belt 1 is returned and corrected.
[0016]
Next, an embodiment of the meandering prevention ribs 1b and 1c in the endless photosensitive belt 1 will be described. Since the meandering prevention ribs 1b and 1c on both side edges have a symmetrical configuration, one meandering prevention rib 1b will be described as an example.
[0017]
FIG. 3 is a cross-sectional view showing an embodiment of the meandering prevention rib 1b in the endless photosensitive belt 1. As shown in FIG. Meandering prevention rib 1b is a meandering preventive ribs substrate 1b ₁ which is formed by thermally vulcanizing silicone rubber constituting adhered to the photosensitive belt substrate 1a by the adhesive 1b ₂ of RTV silicone rubber. The heat vulcanizing silicone rubber preferably has, for example, a hardness HS of 30 ° or more and a tensile strength of 6 MPa or more, and the room temperature curable silicone rubber adhesive has, for example, a tensile strength of 1.5 MPa or more. What has the characteristic is preferable.
[0018]
The meandering prevention rib 1b is always required to have wear resistance in order to come into contact with the taper piece 8a so that the force with which the belt is offset and the force to correct the offset are balanced, and the material is a heat vulcanizing silicone rubber or urethane rubber. Is suitable. Further, since a peeling force or a belt deformation force is applied to the adhesion surface of the meandering prevention rib substrate 1b ₁ , room temperature curable silicone rubber having a stable adhesion force is suitable for the adhesive 1b ₂ . Since this room temperature curable silicone rubber is softer than the heat vulcanizing type, it has an effect of reducing deformation to the belt surface due to a difference in rigidity between the photosensitive belt substrate 1a and the meandering prevention rib 1b at the portion around the roller. Incidentally, when the deformation of the belt surface is large, a crack is generated on the surface, and there is a problem that the crack is printed on the edge of the paper.
[0019]
4 to 7 show modifications of the adhesive surface between the photosensitive belt substrate 1a and the meandering prevention rib 1b.
[0020]
In the embodiment shown in FIG. 4, the notch 1b ₁₁ is formed on both side edges of the adhesion surface of the meandering prevention rib base 1b ₁ so that the adhesion surface is narrow, and the adhesive 1b ₂ is used as the side edge of the meandering prevention rib 1b. It is constructed so that it does not stick out.
[0021]
In the embodiment shown in FIG. 5, as a countermeasure against belt deformation, a plurality of narrow grooves 1b ₁₂ are formed on the contact surface of the meandering prevention rib base 1b ₁ to strengthen the adhesive force and generate belt cracks. In this configuration, the amount of the adhesive 1b ₂ can be increased, and the rigidity reduction effect of the bonded portion can be obtained.
[0022]
In the embodiment shown in FIG. 6, the adhesive 1b ₂ is used as a countermeasure against belt deformation that strengthens the adhesive force and generates belt cracks by forming a wide groove 1b ₁₃ on the contact surface of the meandering prevention rib substrate 1b ₁ . It is possible to increase the amount and obtain the rigidity reduction effect of the bonded portion.
[0023]
In the embodiment shown in FIG. 7, the groove 1b ₁₄ on the contact surface of the meandering prevention rib base 1b ₁ is formed so as to be undercut with respect to the peeling direction to further strengthen the adhesive force.
[0024]
【The invention's effect】
According to the present invention, the meandering prevention rib base is made of heat vulcanized rubber, and the adhesive for adhering the meandering prevention rib base to the belt base is made of a room temperature curing rubber softer than the meandering prevention rib base. Accordingly, to improve the wear resistance with increasing the tear strength and tensile strength of the meandering preventive ribs, it is possible to maintain the surface of the endless belt to a normal state.
[0025]
Particularly in an endless photosensitive belt, high image quality can be maintained.
[Brief description of the drawings]
FIG. 1 is a side view showing an endless photosensitive belt portion in an image forming apparatus according to an embodiment of the present invention.
FIG. 2 is a front view showing a winding structure of an endless photosensitive belt around a driving roller for belt deviation correction according to an embodiment of the present invention.
FIG. 3 is a cross-sectional view showing an example of meandering prevention ribs in the endless photosensitive belt according to the embodiment of the invention.
FIG. 4 is a cross-sectional view showing another example of the meandering prevention rib in the endless photosensitive belt according to the embodiment of the invention.
FIG. 5 is a cross-sectional view showing still another example of the meandering prevention rib in the endless photosensitive belt according to the embodiment of the invention.
FIG. 6 is a cross-sectional view showing still another example of the meandering prevention rib in the endless photosensitive belt according to the embodiment of the invention.
FIG. 7 is a cross-sectional view showing still another example of the meandering prevention rib in the endless photosensitive belt according to the embodiment of the invention.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Endless photosensitive belt 1a Photosensitive belt base | substrate 1b, 1c Meander prevention rib 1b ₁ Meander prevention rib 1b ₂ Adhesive 2 Drive roller 3 Follower roller 4 Tension roller 6 Tension arm 7 Tension spring 8 Taper piece 9 Correction link

Claims (5)

In an endless belt in which a meandering prevention rib base is formed by adhering a meandering prevention rib base with an adhesive to both side edges of the belt base,
An endless belt, wherein the meandering prevention rib base is made of heat vulcanized rubber, and the adhesive is made of a room temperature curing type rubber softer than the meandering prevention rib base . 2. The endless belt according to claim 1, wherein the adhesive surface of the meandering prevention rib base is provided with irregularities into which an adhesive enters. The endless belt according to claim 2, wherein the concave and convex portions have a concave portion formed as an undercut. 4. The endless belt according to claim 1, wherein the endless belt is an endless belt used for any one of a photosensitive belt, an intermediate transfer device, a transfer separation device, a charging device, and a fixing device. Endless belt characterized by. An endless belt is wound around the drive roller, driven roller, and tension roller,
In the image forming apparatus, the tension roller is supported by a tension arm rotatably attached to a support point, and the tension roller is pressed against the endless belt by pulling the tension arm with a tension spring.
The endless belt is the endless belt according to any one of claims 1 to 3,
The tension arm is disposed at both ends of the drive roller, and is pulled back by a correction link that engages with the drive roller and a taper piece that is rotatably arranged with respect to the drive shaft of the drive roller, and thereby the belt tension by the tension roller is increased. Configured to weaken,
2. The image forming apparatus according to claim 1, wherein the meandering prevention rib is positioned on the outer side in the axial direction of the drive roller and is close to the taper piece.

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