JPH04140246A - Belt drive device - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a drive device for a flat belt, particularly a belt drive device for a photoreceptor belt, a transfer conveyance belt, etc. of a device using an electrophotographic method. .

(Prior Art) Conventionally, for example, in an electrophotographic device, a photoreceptor layer or a dielectric layer is formed on the surface of a plurality of roller members arranged substantially parallel to each other in order to make the device lighter and more compact. 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,
This type of flat belt is difficult to deform elastically, so it absorbs dimensional errors in related parts, installation errors in roller members, unbalanced belt tension, and uneven belt circumference by deforming the belt itself. As a result, there was a problem in that meandering was likely to occur when the flat belt ran.

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

As a conventional technique for preventing belt meandering as described above, a guide for preventing meandering is provided on the belt as shown in Japanese Patent Laid-Open No. 56-127501 and Japanese Patent Laid-Open No. 59-205052. , Japanese Patent Publication No. 57-603
As shown in Japanese Patent No. 47, it has been proposed to forcibly prevent the flat belt from meandering by providing a regulating member. Also, Utility Model Application Publication No. 58-110609 and Utility Model Application No. 61-48
Some devices use a complicated mechanism structure to correct meandering, as shown in Japanese Patent No. 457.

(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 forced to stop receiving due to external factors, so it may not be possible to establish the mechanism depending on the conditions of the combination of the flat belt and the roller member. . That is, the greater the shearing force caused by meandering of the flat belt, the greater the strength of the guide and regulating member needs to be. Further, it is necessary to increase the buckling strength of the flat belt itself in the width direction, and at the same time, it is necessary to increase the strength of the end portions of the flat belt so as not to damage the ends thereof. Therefore, if the belt thickness becomes thinner, it becomes difficult to employ the above method. Furthermore, when providing a guide on a flat belt, it is necessary to provide the guide with high precision, and it has been extremely difficult to form this guide, especially in the case of a seamless belt.

In addition, in this type of bell (drive device), slippage may occur between the flat belt and some roller members due to dimensional errors in related parts, installation errors in the roller members, etc. However, the flat belt If the coefficient of friction between the roller member and the
Wrinkles may occur on the flat belt, and damage may occur on the flat belt and roller members.

On the other hand, Utility Model Application No. 58-110609, Utility Model Application No. 64-
The method disclosed in Japanese Patent No. 48457 uses a complicated mechanism to correct the meandering, which is expensive and requires extra space, which not only leads to an increase in the size of the device as a whole, but also requires a complicated mechanism to correct the meandering. The number of points is large, and the number of failure-causing factors increases accordingly, making it difficult to say that the reliability of the device is sufficiently ensured. Also,
As described above, when the coefficient of friction between the flat belt and the roller member is very large, slippage between the two is restricted, which may impede the meandering elimination operation.

On the other hand, if the coefficient of friction between the flat belt and the roller member is small, is the tension of the flat belt increased to ensure that the driving force is transmitted from the mouth member to the flat belt?
This poses a problem in the durability of the flat belt, making it impossible to extend the life of the flat belt.

The coefficient of friction between the flat belt and the roller member is susceptible to the effects of temperature and humidity because they are in direct contact with each other, and it has been difficult to maintain this frictional force constant at a predetermined value. . Another possibility is to form the surface of the force member with an uneven surface to prevent direct contact between the flat belt and the roller member, but this will increase the thrust force as the driving force transmission ability improves. Therefore, the flat belt is likely to be damaged.

The present invention has been made in view of these points, and
Without complicated processing on roller members and flat belts,
To provide a belt drive device which has a simple mechanism, requires a small space, can prevent belt meandering at low cost, and ensures running stability.

(Means for Solving the Problem) In order to achieve the above object, the present invention displaces the spindle of the roller member in a predetermined direction by the running motion force of the flat belt when meandering occurs in the flat belt. This eliminates meandering and prevents damage to the flat belt and roller members. Specifically, the invention according to claim (1) provides a flat belt and a plurality of rollers around which the flat belt is stretched, at least one of which serves as a meandering adjustment roller member with a support shaft displaceably supported. a meandering detection means for detecting meandering of the flat belt, and receiving an output of the meandering detection means and displacing the spindle of the meandering adjustment roller member so as to move the flat belt in a direction opposite to the meandering direction. The roller displacing means is provided, and at least one of the roller members other than the meandering adjustment roller member is configured to have a large number of needle-shaped bodies protruding from the roller surface.

The invention according to claim (2) provides a flat belt, and a plurality of roller members around which the flat belt is stretched, at least one of which serves as a meandering adjustment roller member whose shaft end portion is displaceably supported. A meandering detection means rotatably supported on at least one shaft end of the meandering adjustment roller member independently of the meandering adjustment roller member; and a flat belt connected to the meandering detection means and connected to the meandering detection means. roller displacement means for displacing the shaft end of the meandering adjustment roller member in a predetermined direction by converting the rotational motion into linear motion when the meandering adjustment roller member contacts and a rotational torque is applied; At least one of the roller members other than the roller member for use is configured such that a large number of needle-shaped bodies are protruded from the roller surface.

In the invention described in claim (3), the needle-shaped body is arranged so as to face outward in the radial direction of the roller from the surface of the roller.

In the invention described in claim (4), the needle-like body is made of organic fiber.

The invention described in claim (5) is the belt drive device according to claim (4), in which the needle-shaped body is made of aramid fiber.

The invention described in claim (6) is the belt drive device described in claim (4), in which the needle-shaped body is made of polyester fiber.

The invention described in claim (1) is a belt drive device according to claim (1), (2), or (3), in which the needle-like body is made of carbon fiber.

In the invention described in claim (8), the length of the needle-like body is 1 to 10 m.
I configured it to m.

In the invention described in claim (9), the length of the needle-shaped body protruding from the roller surface is set to 0.01 to 1.

The invention described in claim flol has a structure in which a photoreceptor layer or a dielectric layer is formed on the surface of a flat belt.

(effect) Next, the operation of the present invention with the above configuration will be described.

In the invention described in claim (1), when a meandering line occurs in the flat belt, the meandering detecting means detects the meandering and sends an output to the roller displacement means. Then, the spindle of the meandering adjustment roller member is displaced in a predetermined direction by the operation of the roller displacement means, thereby eliminating the meandering. □At least one of the roller members other than the meandering adjustment roller member has a large number of needle-shaped bodies protruding from the roller surface, so that the frictional force between the roller and the flat belt can be adjusted. If slippage occurs between the roller and the flat belt, allowing the slippage can prevent damage to the roller and the flat belt. Further, since the meandering adjustment roller member is not provided with a needle-shaped body, the coefficient of friction between the meandering adjustment roller member and the flat belt is high, and thereby the meandering elimination operation can be performed reliably.

In the invention as set forth in claim (2), when a meandering line occurs in the flat belt, the flat belt comes into contact with the meandering detecting means, and rotational torque acts on the meandering detecting means. Then, the roller displacement means converts the rotational motion caused by the rotational torque into linear motion, thereby displacing the shaft end of the meandering adjustment roller member in a predetermined direction.

This eliminates the meandering pattern in the same way as the effect of claim (1) described above.

In the invention described in claim (3), the needle-shaped body is disposed so as to face outward in the radial direction of the roller from the surface of the roller, so that the flat belt and the roller do not come into direct contact with each other, and the needle-shaped body can move the flat belt to a predetermined position without directly contacting the roller. It is possible to obtain a coefficient of friction of , and to ensure the holding force of the flat belt in the roller member.

In the invention described in claims (4), (5), (6), and (7), the needle-shaped body can be embodied, and the 1 yen between the flat belt and the roller can be embodied.
The friction coefficient can be easily set.

In the invention described in claim (8), the length of the needle-like body is 1 to 10
+nm, the amount of protrusion from the roller surface is set by polishing the roller or the like. Thereby, the amount of protrusion can be easily set.

In the invention described in claim (9), the necessary friction coefficient between the flat belt and the roller member can be arbitrarily set by setting the protruding length of the needle-shaped body from the roller surface to 0.01 to 1 mm. I can do it.

In the invention described in the claim (lot), by forming a photoreceptor layer or a dielectric layer on the surface of the flat belt, the flat belt can be provided as a photoreceptor belt or a transfer conveyance belt for electrophotography, and can be stably used. Image quality is what you get.

(Example) Hereinafter, an example of the present invention will be described in detail with reference to the drawings.

FIG. 1 shows a flat belt drive housed within an electrophotographic apparatus according to the present invention. In FIG. 1 showing the entire 3-axis photoreceptor belt drive device, 1, 2.3 are as follows:
a first, a second and a thirtieth arm member, each supporting the support shaft 1;
a, 2a, 3a, and elastic rollers lb, 2b formed concentrically with the support shafts 1a, 2a, 3a and having a slightly larger diameter, excluding the left and right ends of the support shafts 1a, 2a, 3a. , 3b. As the material of the elastic rollers 1b, 2b3b, for example, EPDM crosslinked rubber is used.

Further, a photoreceptor belt 4, which is a flat belt in the present invention and has a photoreceptor layer formed on the surface of a base material, is runnably stretched over each of the roller members 1, 2.3. The photoreceptor belt 4 is adapted to function as a photoreceptor of an electronic device.

The base material of the photoreceptor belt 4 is, for example, biaxially oriented polyester, and has a tensile modulus of 2 (
It is set at 10 kg/mm' or more.

The tenth roller member 1 is connected to the support shaft 1a or the drive shaft of the drive motor 5, and can transmit the driving force of the drive motor 5, so that it functions as a so-called drive roller.

The 20th roller member 2 is a so-called driven roller, and its axis is
The tenth member is arranged at an angle with respect to the axis of the member 1.

For example, only the six-direction side shaft end portion of the support shaft 2a is allowed to withstand slight displacement (for example, 1 m) in the C direction with respect to the horizontally parallel position with the 10th member 1.

The 30th radial member 3 is a meandering adjustment roller member according to the present invention, and its axis is arranged substantially parallel to the axis of the 10th radial member 1. Further, the 30th L member 3 is given a biasing force in the C direction by springs 3c, 3c disposed at both left and right axial ends thereof, and the tension of the photoreceptor belt 4 is adjusted by this biasing force. It looks like this.

By arranging each roller member 1, 2.3 in this way, each roller member 1. 2. The photoreceptor belt 4, which is stretched around the photoreceptor belt 3, is configured to always meander in six directions.

Further, as shown in FIGS. 2 and 3, the shaft end portion of the support shaft 3a of the 30th ring member 3 is rotatably supported by the lower frame 8a via a bushing 7, which is a bearing member. The lower frame 8a is engaged with the upper frame 8b fixedly attached to the movable member 6 via the slide ring 9 so as to be able to approach and separate from the shaft end of the tenth member 1. No. 30-Rabu Shrine 3
At a position inside the mounting position of the lower frame 8a of the support shaft 3a, the meandering detection member 11 or the 30th-ra member 3 serves as meandering detection means.
It is disposed coaxially with and rotatably independent of the 30th ring member 3, and a ring member 12 is attached at the outer position.

The meandering detection member 11 has a small gap between its inner end surface and the side end of the elastic roller 3b, and the diameter of the inner end surface is the same as or slightly smaller than the diameter of the elastic roller 3b. There is. The meandering detection member 11 also has a running surface 11a whose diameter increases as it moves away from the end face of the elastic roller 3b, and when meandering occurs in the photoreceptor belt 4, the meandering displacement causes the photoreceptor belt 4 to run It is designed to ride on the surface 11a.

Further, one end of the string member 13 attached and fixed to the fixing member S is connected to the meandering detection member 11, and when the photoreceptor belt 4 meanders, the photoreceptor belt 4 or the other end of the string member 13 is connected to the meandering detection member 11. When the string member 13 is wound around the meandering detecting member 11 due to the rotation of the meandering detecting member 11, the string member 13 is wound around the meandering detecting member 11.
- move the shaft end of the support shaft 3a of the roller member 3 in a direction away from the shaft ends of the support shafts 1a and 2a of the other roller members 1.2, that is,
It is designed to be displaced in the direction B in FIG. This constitutes a roller displacement means that displaces the shaft end of the support shaft 3a in a predetermined direction when rotational torque acts on the meandering detection member 11.

That is, when the shaft end of the support shaft 3a is displaced in the B direction, a meandering component in the direction opposite to the A direction is generated in the photoreceptor belt 4, which cancels out the initial meandering component (A direction component). The shaft end of the support shaft 3a is displaced until the end of the support shaft 3a.

Further, as shown in FIG. 4, a spring 15 is connected to the ring member 12 at the end of the support shaft 3a, so that it is always biased in the opposite direction to the direction in which the string member 13 is displaced by the winding operation. The spring 15 suppresses displacement of the shaft end portion of the support shaft 3a by a predetermined amount or more. With this configuration, when the meandering component in the opposite direction due to the displacement of the shaft end of the support shaft 3a becomes larger than the initial meandering component,
The photoreceptor belt 4 starts meandering in the opposite direction, and the amount of riding on the meandering detection member 11 decreases, so the meandering detection member 11
The rotational torque of the support shaft 3a is also reduced, and as a result, the amount of displacement of the shaft end of the support shaft 3a by the spring 15 is also reduced.

Further, movement of the meandering detection member 11 toward the outside of the roller end is regulated by a stopper 16 .

As a feature of this example, as shown in FIG. 6, each of the roller members 1. 2. 3, each of the rollers 1b and 2b of the 1st member 1 and the 20th member 2 (FIG. 6 shows the 10th member 1) has a length of 11 to
Aramid fibers as multiple needle-shaped bodies formed to 10 mm 17.17. ... is contained, and a portion of the aramid fibers 17 protrudes radially outward from the rollers lb and 2b by a distance of 101 to 1 m+a.In other words, when the belt drive device is driven, the first and The rollers lb and 2b of the 20th roller member 1.2 are configured so that they do not contact the photoreceptor belt 4 directly but through this aramid fiber layer. body roller 1
After kneading the aramid fibers 17 into the rubber during molding of parts b and 2b, by polishing the surfaces of the elastic rollers 1b and 2b,
Aramid fiber] 7 is obtained by protruding a part of the fiber.

As for the operation of the present belt drive device having the above-described configuration, first, the second
Due to the inclined arrangement of the O-ra member 2, a force always acts on the photoreceptor belt 4 so as to displace it in the A direction.

Therefore, due to the displacement of the photoreceptor belt 4, the photoreceptor belt 4
When the end of the meandering detecting member 11 rides on the shaft 11H, as shown in FIG. 2a, and the string member 13 is wound up by the rotation.

By winding up the string member 13, the shaft end of the support shaft 3a, which is the end of the 30th member 3 on which the meandering detection member 11 is disposed, is displaced, and due to this displacement, the photoreceptor belt 4 is moved in the A direction. The photoreceptor belt 4 travels while being wound in the opposite direction, thereby controlling the displacement of the photoreceptor belt 4 in the incoming direction. At the same time, due to the displacement of the shaft end, the spring 15 is extended and a spring force is also applied, so the balance between the winding force of the string member 13 and the spring force of the spring 15 causes the displacement of the 30th-ring member 3. The amount is regulated, and the end of the photoreceptor belt 4 is maintained at a certain constant position.

Since the photoreceptor belt 4 travels in this manner, the meandering of the photoreceptor belt 4 is eliminated, and the amount of meandering of the photoreceptor belt 4 can be suppressed to, for example, 10-odd micrometers.

Since the aramid fibers 17 are protruded on the surfaces of the elastic rollers lb and 2b, the coefficient of friction between the elastic rollers 1b and 2b and the photoreceptor belt 4 is adjusted to an appropriate level of 9 when driven. Because of this setting, if slippage occurs between the two, this slippage is allowed and damage to the photoreceptor belt 4 and the elastic rollers lb, 2b is prevented. In addition, since the two are not in direct contact, the interface state is not affected by humidity or temperature. Therefore, the friction coefficient does not change depending on the environment and the running condition does not change, so the running condition is always stable. It is possible to obtain the running condition. Further, since the highly rigid fibers are in contact with the photoreceptor belt 4, the roller lb.

The holding force of the photoreceptor belt 2b to the photoreceptor belt 4 is sufficiently ensured, and the driving force from the tenth member 1 is reliably transmitted, which also allows the photoreceptor belt 4 to run stably. . Furthermore, aramid fibers 17 are provided on the 30th roller member 3, which is a meandering adjustment roller member, and the coefficient of friction between the 30th roller member 3 and the photoreceptor belt 4 is higher than that of other roller members. 1. 2 and the photoreceptor belt 4, this third
The meandering elimination operation in the 0-ra member 3, that is, the displacement movement of the photoreceptor belt 4 in the direction opposite to the direction A, is reliably performed, and the meandering elimination operation is performed smoothly.

In the configuration of this example, the protruding length of the needle-shaped body can be arbitrarily changed between 0.01 and 1 mm depending on the system requirements and the required friction coefficient between the belt and the roller.

In this example, the aramid fibers 17 are placed on the elastic roller 2b,
3b, and this elastic roller 2b.

Either the aramid fibers 17 are made to protrude from the surface by polishing the aramid fibers 3b, or the aramid fibers 17 are made to protrude from the surface of the
It may also be configured to be directly adhered to the surface.

Furthermore, in this example, the rollers lb and 2b are made of aramid fibers 17.
However, the present invention is limited to aramid fibers, and other organic fibers (e.g., PET, nylon, etc.)
Alternatively, carbon fiber or inorganic acicular filler (for example, silicon carbide, iron oxide, etc.) may be used.

It should be noted that the meandering detection member 11 of this example is arranged only on one side of the 30th La part shrine 3, but the present invention is not limited to this.
It may also be configured such that they are arranged at both left and right ends. Further, the structure may be such that two or more meandering adjustment roller members are provided with meandering detection members.

In addition, in this example, the 20th L member 2 is arranged at an angle so that the photoreceptor belt 4 meanders in the A direction in advance, but the 20th L member 2 is arranged parallel to the 10th L member 1. arranged,
In addition, the 30th round part shrine 3 may be arranged at an angle so that the photoreceptor belt 4 meanders in advance in the A direction.

Further, in the above-mentioned embodiments, an example is explained in which the application is applied to a photoreceptor belt drive device of an electrophotographic apparatus, but the present invention is not limited thereto, and may be applied to a drive device of a transfer conveyance device or a normal flat belt drive device. The same can be applied to devices.

Further, the present invention is not limited to a method in which meandering is detected by a meandering flat belt coming into contact with a meandering detection member, and in addition, the present invention is limited to a method in which meandering is detected by using various means such as an optical sensor. It can be applied to anything that has been done.

(Effects of the Invention) As described above, according to the present invention, the following effects are achieved.

According to the invention set forth in claim (1), at least one of the roller members other than the meandering adjustment roller member has a large number of needle-like bodies protruding from the roller surface, so that the roller and the flat belt are By adjusting the thick friction force between the roller and the flat belt, if slipping occurs between the roller and the flat belt, by allowing the slipping, damage to the roller and the flat belt can be prevented, and the reliability of the device can be improved. Furthermore, since the meandering adjustment roller member is not provided with any needle-shaped bodies, the coefficient of friction between the meandering adjustment roller member and the flat belt is high, and thereby the meandering elimination operation can be performed reliably.

According to the invention set forth in claim (2), the shaft end of the meandering adjustment roller member is moved to a predetermined position by converting the rotational motion caused by the rotational torque acting on the meandering detection means by the flat belt into linear motion by the roller displacement means. Since the meandering is eliminated by displacement in the direction, a mechanism for eliminating meandering can be obtained with a simple structure.

According to the invention set forth in claim (3), the needle-shaped body is disposed from the surface of the roller toward the outside in the radial direction of the roller, so that the flat belt and the roller do not come into direct contact with each other. , a predetermined coefficient of friction can be obtained, and a sufficient holding force of the flat belt in the roller member can be ensured.

According to the invention described in claims (4), 15), (6), and (7), the needle-like body can be embodied, and the friction coefficient between the flat belt and the roller can be easily set. .

According to the invention described in claim (8), the length of the needle-like body is 1 to 1.
By setting the length to 10 mm, the amount of protrusion from the roller surface can be easily set by polishing the roller or the like.

According to the invention set forth in claim (9), the necessary friction coefficient between the flat belt and the roller member can be arbitrarily set by setting the protrusion length of the needle-shaped body from the roller surface to 0.01 to 1 m+++. This can improve practicality.

According to the invention of claim (10), since a photoreceptor layer or a dielectric layer is formed on the surface of the flat belt, it can be provided as an electrophotographic photoreceptor belt or a transfer conveyance belt, and it can provide stable image quality. can get.

[Brief explanation of drawings]

1 to 6 show one embodiment of the present invention, FIG. 1 is a schematic perspective view of a belt drive device, FIG. 2 is a longitudinal sectional front view of the vicinity of the meandering detection member, and FIG. 3 is a view from inside thereof. Perspective view, 4th
The figure is a perspective view seen from the outside, FIG. 5 is a diagram for explaining the operation of the roller displacement means, and FIG. 6 is a partially cutaway front view of the 10th roller member. 1. 10th La member 2... 20th La member 3... 30th La member (meandering adjustment roller member) la
, 2a, 3a・Support shaft lb, 2b, 3b・Elastic roller photoreceptor belt (flat belt) 11...Meandering detection member (meandering detection means) 17.Aramid fiber (acicular body) Patent application Jinjin Bunt - Kagaku Co., Ltd., π) r Sea □ + 1 no Mae 1) Hiroshi Haka 1 person Figure Figure Figure 1 ・10th-Ra member 2・20th-Ra member 3...30th - La member (Meandering detection port 1a2a, 3a
...Support shafts 1b2b, 3b...Elastic roller 4...Photoreceptor belt (flat belt) 17...Aramid fiber (needle-like member) 3C1 搗ト伜/

Claims (10)

[Claims] (1) A flat belt, a plurality of roller members around which the flat belt is stretched, at least one of which serves as a meandering adjustment roller member whose spindle is displaceably supported, and detecting meandering of the flat belt. Meandering detection means; and roller displacement means for receiving the output of the meandering detection means and displacing the spindle of the meandering adjustment roller member so as to move the flat belt in a direction opposite to the meandering direction; A belt drive device characterized in that at least one of the roller members other than the roller member has a large number of needle-shaped bodies protruding from the roller surface. (2) a flat belt; a plurality of roller members around which the flat belt is stretched, at least one of which serves as a meandering adjustment roller member whose shaft end portion is displaceably supported; and the meandering adjustment roller member. Meandering detection means rotatably supported on at least one shaft end independently of the meandering adjustment roller member, and a flat belt connected to the meandering detection means and in contact with the meandering detection means to apply rotational torque. and a roller displacement means for displacing the shaft end of the meandering adjustment roller member in a predetermined direction by converting the rotational motion into a linear motion when the meandering adjustment roller member is moved. One is a belt drive device characterized by a large number of needle-shaped bodies protruding from the roller surface. (3) The belt according to claim (1) or (2), wherein the needle-like body is arranged from the surface of the roller to the outside in the radial direction of the roller. Drive device. (4) Claims (1), (2), or (3) characterized in that the needle-like bodies are made of organic fibers.
Belt drive device as described in section. (5) The belt drive device according to claim (4), wherein the needle-like body is made of aramid fiber. (6) The belt drive device according to claim (4), wherein the needle-like body is made of polyester fiber. (7) Claims (1), (2), or (3) characterized in that the needle-like body is made of carbon fiber.
Belt drive device as described in section. (8) Claims (1), (2), and (3) characterized in that the needle-like body has a length of 1 to 10 mm.
, (4), (5), (6), or (7). (9) The protruding length of the needle-shaped body from the roller surface is 0.0
Claim No. 1, characterized in that the diameter is 1 to 1 mm.
1), (2), (3), (4), (5), (
6), the belt drive device according to item (7) or item (8). (10) Claims (1), (2), (3), and (4) characterized in that the flat belt has a photoreceptor layer or a dielectric layer formed on its surface. , (5), (6), (7), (8), or (9).