JPH04148744A - Manufacture of roller member for belt drive device - Google Patents

Abstract

PURPOSE:To facilitate the manufacture of a tapered roller member by fitting tapered pieces in which respective shaft holes are bored, with their smaller diameter ends located on the inner sides over both ends of the rotary shaft extending beyond a roller member of a uniform diameter. CONSTITUTION:A driven roller member 3 comprises a straight cylindrical portion 33 of a uniform diameter and tapered pieces 34 connected to both ends of the straight portion 33 with its belt contact surface made of compound elastomer 35. The tapered piece 34 is tapered inward and made to have a friction coefficient greater than that of said belt contact surface. When manufacturing this driven roller member 3, the straight portion 33 is made through which a driven shaft 32 is inserted with its both ends extending beyond both ends of the straight portion 33. The tapered piece 34 is made separately with a shaft hole 34a bored therethrough and fitted with its smaller diameter end located on the inner side over the shaft 32 on both sides of the straight portion 33. Thus the manufacture of the tapered driven roller member 3 is facilitated.

Description

Detailed Description of the Invention (Industrial Application Field) The present invention relates to flat belt drive devices, particularly roller members in belt drive devices such as photoreceptor belts and transfer conveyance belts of equipment using electrophotography. The present invention relates to a manufacturing method.

(Prior Art) Conventionally, for example, in an electrophotographic apparatus, for the purpose of making the apparatus lighter and more compact, a plurality of roller members arranged substantially parallel to each other have a surface formed with a photosensitive layer or a dielectric layer. It is known to span a flat belt and use the flat belt as a photoconductor belt or a transfer conveyance belt instead of a photoconductor drum.

However, flat belts used for such purposes are often formed from a material with low elongation and high strength, such as a plastic film or metal foil, as a base material. Therefore,
Since this type of flat belt is difficult to deform elastically, it is possible to absorb dimensional errors in related parts, installation errors in roller members, unbalanced belt tension, uneven belt circumference, etc. by deforming the belt itself. As a result, there is a problem in that meandering tends to occur when the flat belt runs.

However, in such an electrophotographic apparatus, high precision and high resolution are required in order to perform accurate image formation, so it is necessary to prevent the flat belt from meandering.

As a conventional technique for preventing such belt meandering, a guide for preventing meandering is provided on the belt as shown in Japanese Patent Application Laid-open No. 56-127501 and Japanese Patent Application Laid-open No. 59-205052. , Japanese Patent Publication No. 57-6034
As shown in Japanese Patent No. 7, it has been proposed to forcibly prevent meandering of the flat belt by providing a regulating member. Also,
Utility Model Application Publication No. 58-110609 and Utility Model Application No. 64-484
As shown in Japanese Patent No. 57, there are some devices that use a complicated mechanism structure to correct meandering.

(Problem to be solved by the invention) However, JP-A-56-127501, JP-A-59-205052 and JP-A-57-6034
In the configuration shown in Publication No. 7, the flat belt is forcibly stopped by an external member, so the strength of the guide and regulating member must be reduced as the shifting force increases as the flat belt meanders. need to be increased. Further, it is necessary to increase the buckling strength in the width direction of the flat belt itself, and at the same time, it is necessary to increase the edge strength. Further, when providing a guide on a flat belt, it is necessary to provide the guide with high precision, and especially in the case of a seamless belt, forming the guide itself is extremely difficult.

Also, Utility Model Application Publication No. 58-110609, Utility Model Application No. 64-
The method disclosed in Japanese Patent No. 48457 uses a complicated mechanism to correct meandering, which is expensive and requires extra space, and the complicated mechanism has a large number of parts, which increases the number of parts that cause failures. Therefore, the reliability was low.

Therefore, both ends of one roller member are made variable, and
It has been considered to form tapered portions on both sides of one roller member, so that when the flat belt meanderes and rides on the tapered portion, one end of the roller member is displaced to correct the meandering.

However, in this belt drive device, if the parallel portion and the tapered portion of the tapered roller member are integrally processed, there is a problem in that productivity is low. In other words, since the round bar material is cut, there are problems in that productivity is low and costs are high.

Furthermore, when the roller member is made of a rubber material, there is a problem in that the dimensions vary widely.

On the other hand, if a metallic roller member is used, there is a problem that if foreign matter gets mixed in between the roller member and the flat belt, the flat belt will become damaged and damaged due to unevenness.

The present invention has been made in view of the above, and aims to improve the productivity of a roller member with a tapered portion and extend its life.

(Means for Solving the Problems) In order to achieve the above object, the means taken by the present invention are as follows:
The parallel part and the tapered part are created separately.

Specifically, the means taken by the invention according to claim (1) is that first, a flat belt is runnably stretched around a plurality of roller members, and at least one of the plurality of roller members is In a belt drive device, the belt drive device is composed of a parallel part formed to have a substantially uniform outer diameter and equipped with a rotating shaft, and a tapered part provided at both ends or one end and having a larger diameter toward the outside. The subject is a method for manufacturing roller members.

Then, while a parallel portion is produced by making the rotating shaft protrude to both sides, a tapered portion in which a shaft hole is formed separately from the parallel portion is produced. Thereafter, the tapered portion is fitted onto the rotating shaft of the parallel portion with its small diameter side facing inside.

In addition, the measures taken by the invention according to claim (2) are as follows:
A flat belt is freely runnable around a plurality of roller members, and a few of the plurality of roller members (one roller member is a parallel belt having a substantially uniform outer diameter and a rotating shaft). and a tapered part provided at both ends or one end and having a larger diameter toward the outside, and at least one roller corresponding to at least the end on the tapered part side of the roller member with a tapered part. The present invention is directed to a method of manufacturing a roller member in a belt drive device in which the end portion of the member is supported movably in a predetermined direction perpendicular to the rotational axis so that the belt tension can be varied by a roller support member.

Then, while a parallel portion is produced by making the rotating shaft protrude to both sides, a tapered portion in which a shaft hole is formed separately from the parallel portion is produced. Thereafter, the tapered portion is fitted onto the rotating shaft of the parallel portion with its small diameter side facing inside.

(Function) With the above configuration, in the invention according to claim (1), the roller member with a tapered portion is manufactured by separately manufacturing the parallel portion and the tapered portion, and then attaching the parallel portion and the tapered portion. That will happen.

Then, the flat belt runs between the plurality of roller members due to the rotation of the drive-side roller member.

In particular, in the invention according to claim (2), when the flat belt snakes, the side end of the flat belt rides on the tapered part of the roller member with a tapered part, the tension on the end side increases, and the flat belt It moves in the opposite direction to the meandering direction, and the meandering of the flat belt is automatically corrected.

(Freezing effect of the invention) Therefore, according to the invention according to claim (1), since the tapered portion and the parallel portion are manufactured separately to manufacture the roller member with the tapered portion, the tapered portion and the parallel portion are manufactured separately. Since the roller member can be manufactured easily and productivity can be improved, it can be made inexpensive.

Further, when the roller member with the tapered portion is formed of an elastic material such as a rubber material, it is possible to manufacture a high-precision bearing member with little variation in dimensions.

Further, according to the invention according to claim (2), when the flat belt meanderes using the roller member with the tapered portion, the tension at the end of the flat belt on the meandering side increases. As a result, the meandering is automatically and reliably corrected, so that the flat belt can run stably, and especially when applied to an electrophotographic apparatus, reliable image formation can be performed.

Furthermore, since there is no guide member or the like as in the conventional belt, the flat belt is not damaged and its life can be extended. Furthermore, since meandering can be corrected with a simple configuration, it can be applied to various devices.

Furthermore, if the parallel portions of the tapered roller member are formed of fiber composite elastomer, foreign matter will be less likely to get mixed in between the flat belt and the roller member, and damage to the belt can be prevented.

(Example) Hereinafter, an example of the present invention will be described in detail based on the drawings.

As shown in FIG. 1, reference numeral 1 denotes a belt drive device, which is provided in an electrophotographic apparatus. The belt drive device 1 is configured such that a photoreceptor belt 4 is stretched between a driving roller member 2 and a driven roller member 3.

The photoreceptor belt 4 is composed of a wide flat belt, and although not shown, a photoreceptor layer is laminated on the surface of a base material, and the photoreceptor belt 4 functions as a photoreceptor in an electrophotographic apparatus. are doing.

Further, as the base material of the photoreceptor belt 4, for example, 2
Axially oriented polyester is used, and the tensile modulus is 2.
．． 00 kg/am' or more.

The drive-side roller member 2 is made up of a large-diameter elastic roller 21 and a small-diameter drive shaft 22 fitted and fixed thereto. Although not shown, both ends are rotatably supported by a fixed member.

A drive motor 23 is directly connected to one end of the drive shaft 22.

On the other hand, the driven roller member 3 is a roller member that is a feature of the present invention, and is constructed by fitting and fixing a small-diameter driven shaft 32 into a large-diameter roller main body 31, as shown in FIG. ing. The roller body 31 is made up of a parallel part 33 which is a perfect circle with a substantially uniform diameter, and tapered parts 34, 34 are connected to both ends of the parallel part 33, and the surface of the parallel part 33, which is the belt contact surface, is made of fiber composite elastomer. It consists of 35. The fiber composite elastomer 35 is an elastomer that is a composite of organic short fibers such as polyester fibers and aramid fibers, and is formed with the organic short fibers exposed on the surface so that the coefficient of friction against the photoreceptor belt 4 is reduced. It is configured. The blending amount of the short fibers is preferably 10 to 30% by volume, and the exposed length of the surface is preferably 0.01 to 11IIIl.

Further, the tapered portion 34 is formed in a tapered shape with a diameter increasing outward on both the left and right sides, and has a friction coefficient set to be larger than the friction coefficient of the belt contact surface made of the fiber composite elastomer 35. When the photoreceptor belt 4 meanders, the end portion of the belt rides on the tapered portion 34 to correct the meandering.

On the other hand, both ends of the driven shaft 32 are connected to roller support members 5, 5.
The roller support member 5 includes a bearing 51, a spring 52 attached to the bearing 51, and, although not shown, a fixed support having a long hole or the like into which the driven shaft 32 is inserted. It is made up of materials. The roller support member 5 is connected to the driven shaft 32 in the direction in which tension is applied to the photoreceptor belt 4, that is, in the direction in which the driven roller member 3 approaches and separates from the drive roller member 2.
The end of the frame is movably supported. Furthermore, the bearing 51
．． is rotatably fitted around the driven shaft 32, and the spring 52 has one end attached to a fixed member, and the driven shaft 32 is rotated in the direction of tension so as to apply tension to the photoreceptor belt 4. In other words, it is pulled in a direction away from the drive-side roller member 2.

Next, the operation of the belt drive device 1 will be explained together with the meandering correction operation.

First, when the photoreceptor belt 4 is stretched around both roller members 2.3, the driven roller member 3 is held against the spring 5.
2.52 in the direction away from the drive-side roller member 2, a predetermined tension is applied to the photoreceptor belt 4.

In this state, when the drive motor 23 is driven, the drive-side roller member 2 rotates and the photoreceptor belt 4 runs between the two-end roller members 2 and 3.

While the photoreceptor belt 4 is running, if the photoreceptor belt 4 meanders, for example, in the direction A in FIG.
The end of the photoreceptor belt 4 on the sideward direction rides on the tapered portion 34 . The end of the driven roller member 3 on the A direction side is slightly displaced in the direction approaching the driving roller member 2, while the end of the photoreceptor belt 4 on the A direction side is driven by the spring force of the spring 52. axis 32
Since it is being stretched, tension is applied to the photoreceptor belt 4, and a force is generated on the photoreceptor belt 4 in the opposite direction to the meandering direction (opposite to the direction A), so that the meandering is corrected.

Next, a method of manufacturing the driven roller member 3, which is a feature of the present invention, will be explained.

As shown in the third factor, first, the parallel part 33 of the driven roller member 3 is made, that is, the surface of the cylindrical material is formed of the fiber composite elastomer 35, and the driven shaft 32 is inserted into the parallel part 33, Both ends of the driven shaft 32 are made to protrude to both sides of the parallel portion 33, thereby fixing the parallel portion 33 and the driven shaft 32.

On the other hand, a tapered part 34 is produced separately from the parallel part 33, that is, the outer peripheral surface is formed into a tapered shape, and the shaft hole 3
Drill 4a.

After that, the driven shaft 32 is inserted into the shaft hole 34a of the tapered part 34, the tapered part 34 is fixed to the driven shaft 32, and the driven shaft 34 is fixed to the driven shaft 32.
The production of the side roller member 3 is completed.

In other words, if the parallel part 33 and the tapered part 34 were formed integrally, for example, if they were cut from a round bar, the productivity would be low and the cost would be high. If it is made of an elastic material, there will be large variations in dimensions. Therefore, after forming the parallel portion 33 and the tapered portion 34 separately, they are attached.

Therefore, since the tapered portion 34 and the parallel portion 33 are manufactured separately to manufacture the driven roller member 3 with the tapered portion, the driven roller member 3 can be easily manufactured. Since productivity can be improved, it can be made inexpensive.

Further, when the driven roller member 3 is formed of an elastic material such as a rubber material, it is possible to manufacture a highly accurate roller member with little variation in dimensions.

Further, it is possible to easily manufacture the driven roller member 3 in which the parallel portion 33 and the tapered portion 34 are made of different materials.

Furthermore, roller members 3a and 3 shown in FIGS. 4 and 5
b can be easily produced. In other words, as shown in FIG. 4, it is possible to easily manufacture a roller member 3a in which a true inner portion 34c having the same diameter as the parallel portion 33 is formed at the inner end of the tapered portion 34. Moreover, as shown in FIG.
Roller member 3 with tapered surfaces 33b formed at both ends of 3a
(b) can be easily manufactured, and a roller member corresponding to the type of belt can be easily manufactured to prevent the belt from waving.

On the other hand, the reason why the belt contact surface of the parallel portion 33 is made of the fiber composite elastomer 35 as described above is that the friction coefficient is large.
This is to reduce the coefficient of friction since the biasing force of meandering increases and correction becomes difficult.

Therefore, when the friction coefficient of the material of the roller member with respect to the belt was measured, the results as shown in Table 1 were obtained.

The principle of the measuring device used in this measurement is that, as shown in FIG. It is provided. Then, the load of the weight 82 is set to 0°385Kg and 1.75Kg.
The wind speed of the roller member 83 is 36a+a+
/S, the load is measured with the load cell 81 for 30 seconds. From these, the friction coefficient μ is calculated using the following formula (■).

u − (2XI n (TI /T2) ) /π
-... ■T1: Detected load T2 of the feed cell 81: Load table 1 of the weight 82 From Table 1 above, the driven roller member 3 is made of the fiber composite elastomer 35 to reduce the coefficient of friction.

Therefore, according to the belt drive device 1 provided with the driven roller member 3 with the tapered portion, when the photoreceptor belt 4 meanders, the tension at the end of the belt on the meandering side increases, and the driven roller member 3 This results in a decrease in the coefficient of friction on the meandering side. As a result, the meandering is automatically and reliably corrected, so that the photoreceptor belt 4 can run stably, and particularly when applied to an electrophotographic apparatus, reliable image formation can be performed.

In addition, since a guide member or the like is not provided as in the conventional case, the photoreceptor belt 4 is not damaged and its life can be extended. Furthermore, since meandering can be corrected with a simple configuration, it can be easily applied to electrophotographic apparatuses.

Moreover, since the driven roller member 3 is made of the fiber composite elastomer 35, the friction coefficient of the driving roller member 2 is increased, and reliable belt transmission can be performed.

In addition, since the friction coefficient in the thrust direction of the driven roller member 3 is reduced, meandering can be corrected by reducing the amount of displacement, that is, the amount of twist, of the roller member 3, and the frictional force can be applied to the photoreceptor. Belt 4. Since it is difficult to be influenced by the interface state between the roller member 3 and the driven roller member 3,
Environmental stability can be improved.

Further, since it is made of the fiber composite elastomer 35, foreign matter is less likely to get mixed in between the photoreceptor belt 4 and the driven roller member 3, and damage to the belt can be prevented.

Although this embodiment has been described with respect to an electrophotographic apparatus, the present invention may be applied to various apparatuses such as a transfer conveyance apparatus.

Further, in this embodiment, one driven roller member 3 is used, but a plurality of driven roller members 3 may be provided. In that case, the tapered portion 34 and the fiber composite elastomer 35 may be provided on at least one roller member. In addition, the tapered portion 34 may be provided only on one side,
Furthermore, the tapered roller member 3 and the roller member whose end portion is displaced may be separate.

Furthermore, the drive-side roller member 2 is not limited to the elastic roller 21.

Moreover, it goes without saying that the invention according to claim (1) can be applied to a roller member with a tapered portion that is not supported by the spring 52 or the like.

[Brief explanation of the drawing]

The drawings show an embodiment of the present invention, and FIG. 1 is an overall perspective view of a belt drive device, and FIG. 2 is a front view of a driven roller member. Figure 3 is an exploded perspective view of the driven roller member;
4 and '1s5 are front views showing other roller members. FIG. 6 is a schematic diagram of the friction coefficient measuring device. 1... Belt drive device 2... Drive side roller member 3... Driven side roller member (roller member with a tapered portion) 4... Photoreceptor belt (flat belt) 5... Roller support member 33.・Parallel portion 34 ・Tapered portion 35 ・Fiber composite elastomer 52 ・Spring

Claims (2)

[Claims] (1) A flat belt is freely runnable around a plurality of roller members, and at least one of the plurality of roller members has a substantially uniform outer diameter and is provided with a rotating shaft. A method for manufacturing a roller member for a belt drive device, which comprises a parallel portion and a tapered portion provided at both ends or one end and having a larger diameter toward the outside, wherein the rotating shaft is protruded to both sides. At the same time, create a tapered part with a shaft hole drilled separately from the parallel part, and then fit the tapered part to the rotating shaft of the parallel part with its small diameter side inside. A method of manufacturing a roller member in a belt drive device, characterized in that: (2) A flat belt is freely runnable around a plurality of roller members, and at least one of the plurality of roller members is formed to have a substantially uniform outer diameter and is provided with a rotating shaft. It is composed of a parallel part and a tapered part provided at both ends or one end and whose diameter becomes larger toward the outside, and at least one tapered part corresponding to at least the end on the tapered part side of the roller member with a tapered part. A method for manufacturing a roller member in a belt drive device, wherein the end portion of the roller member is supported by a roller support member so as to be movable in a predetermined direction perpendicular to the rotational axis so that the belt tension can be varied, the method comprising: A parallel part is created by making the shaft protrude to both sides, and a tapered part with a shaft hole is created separately from the parallel part, and then the tapered part is turned into a parallel part with its small diameter side inside. A method for manufacturing a roller member in a belt drive device, the roller member being fitted onto a rotating shaft.