JP2008007246A - Belt adjusting device, belt adjusting method, and belt conveyance device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a belt conveyance device used to convey parts to make a close inspection of precision parts, in particular, a belt conveyance device having: a conveyor steel-made belt having large width, and a small interval between a driving pulley and a driven pulley; a belt adjusting device for adjusting a running position of the belt with desired high precision; and a belt adjusting method. <P>SOLUTION: The belt adjusting device which prevents meandering of the belt driven by a pulley and conveying articles to adjust its circumferentially moving position, is provided with: a position detection means for detecting a reference position in the circumferential direction of the belt per circumferential turn of the belt; a displacement detection sensor for detecting an amount of displacement for a reference position in the transverse direction of the belt at the reference position in the circumferential direction, and a pulley control mechanism for controlling arrangement of the pulley so as to make a difference in circumferential length between a belt edge on one side and a belt edge on the other side in accordance with the amount of displacement. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a belt adjusting device and a belt adjusting method, and more specifically, a belt adjusting device, a belt adjusting method, and a belt adjusting method that adjust a traveling position by preventing meandering of a belt that is driven by a pulley and conveys an article. The present invention relates to a transport device including the device.

As an apparatus for conveying various articles, a conveying apparatus having a belt is generally used. As an example, in a manufacturing process of a BGA (Ball Grid Array) type semiconductor package, a belt transfer device is used in which the manufactured BGA type semiconductor package is transferred to an image processing inspection device for product defect inspection and inspection is performed. Is used.
However, in a belt conveying apparatus used for conveying parts in such a precision part inspection, a device for adjusting the belt traveling position with high accuracy is required.
Here, as a mechanism for stabilizing the traveling position, a meshing mechanism using a gear and a groove is conceivable. However, when the belt is made of steel, if a groove for gears is provided in the belt, the belt that is used under a large tension breaks from the portion of the groove, compared to a belt that does not have a groove. Durability will be significantly reduced.
On the other hand, a mechanism for adjusting the traveling position with high accuracy by providing flanges at both ends of the pulley supporting the belt is also conceivable. However, when the belt is made of steel, the belt edge is in contact with the flange, so that the durability of the belt is significantly reduced as compared with the case where no flange is provided at both ends of the pulley.
Therefore, in a belt conveyance device using a steel belt, a pulley having no meshing mechanism or flange is used.
With such a pulley, it is difficult to adjust the belt position, and it is particularly difficult to adjust the belt position with high accuracy.

A belt adjusting device for a belt conveying device using a conventional meshing mechanism and a pulley having no flange is described in JP-A-6-305542 and includes a belt adjusting device 110 shown in FIG. Has been proposed.
In this conventional example, in a belt device 110 that conveys an article placed on the belt 116 by passing the belt 116 around at least two drive pulleys 113 and 114, the crossing angle of the one drive pulley 114 with respect to the belt 116 is set. A meandering correction device 120 that changes and corrects the meandering of the belt 116 and a tension applying device 117 that presses the other driving pulley 113 against the belt 116 are characterized.
According to this conventional example, as shown in FIG. 6, one drive roller 114 on which the belt 116 is stretched changes the crossing angle with respect to the belt 116 by the meandering correction device 120, and the other drive roller 113 also has this. Since the crossing angle changes following this, the meandering of the belt is quickly corrected. In addition, since the other driving roller 113 is always pressed against the belt by the tension applying device 117, the pressure on the belt of the other driving roller 113 is adjusted in response to the change in the angle of the one driving roller 114, and The driving force can be reliably maintained. In this apparatus, the belt position is adjusted by controlling the drive pulley 114 while the detection unit 130 constantly detects the belt position.

JP-A-6-305542

  Even with the conventional belt adjusting device shown in FIG. 6, it is possible to adjust the belt position which does not require so high accuracy. However, as the belt is made of steel and the distance between the driving pulley and the driven pulley is narrower and the width of the belt is wider, it is conventionally difficult to control the belt position adjustment with a desired high accuracy. It was supposed to be.

  The present invention has been made in view of the above circumstances, and is a belt conveying device used for conveying parts in precision inspections of precision parts. In particular, the conveying belt is made of steel, and a driving pulley and a driven pulley. Belt adjusting device, belt adjusting method and belt adjusting device capable of adjusting the belt running position with a desired high accuracy with respect to a belt having a narrow width and a wide belt width. The purpose is to do.

  The present invention solves the above-described problems by the solving means described below.

  A belt adjustment device according to the present invention detects a belt reference position in the belt adjustment device for each belt rotation in a belt adjustment device that adjusts a running position by preventing meandering of a belt that is driven by a pulley to convey an article. A position detection means, a displacement detection sensor for detecting a displacement amount relative to the lateral reference position of the belt at the circumferential reference position, and a belt edge between one belt edge and the other belt edge according to the displacement amount; And a pulley control mechanism for controlling the arrangement of the pulleys so as to cause a length difference.

  Storage means for storing the first displacement amount, which is the displacement amount with respect to the lateral reference position of the belt, which is detected first, and the second displacement amount which is detected after one round of the belt; The calculating means for calculating the difference between the first displacement amount and the second displacement amount, and depending on the value of the difference, a circumferential length difference is generated between one belt edge and the other belt edge. And a pulley control mechanism for controlling the arrangement of the pulleys.

  The pulley whose arrangement is controlled by the pulley control mechanism is a driven pulley.

  Here, it is effective that the displacement detection sensor is provided at a position immediately after the belt passes through the driven pulley.

  In addition, a rear displacement detection sensor for detecting the rear displacement amount of the belt is provided at a position behind the position where the displacement detection sensor is installed and where the belt approaches the drive pulley, and according to the rear displacement amount, It is characterized by comprising a pulley control mechanism for controlling the arrangement of the driven pulley so as to generate a circumferential length difference between one belt edge and the other belt edge.

  In addition, the pulley control mechanism rotates around the intermediate point on the rotation axis of the driven pulley in the same plane that includes the rotation axis of the drive pulley and the rotation axis of the driven pulley. A pulley operating unit that controls the arrangement of the driven pulley so as to cause a length difference is provided.

  The belt adjustment method according to the present invention is a belt adjustment method for adjusting a traveling position by preventing meandering of a belt that is driven by a pulley to convey an article, and detects a reference position in the circumferential direction of the belt for each rotation of the belt. The pulley detects a displacement amount with respect to the lateral reference position of the belt at the circumferential reference position, and generates a circumferential length difference between one belt edge and the other belt edge according to the displacement amount. The first displacement amount is stored as the first displacement amount, and the first displacement amount detected after one round of the belt is stored as the second displacement amount. The difference between the amount and the second displacement amount is calculated, and the arrangement of the pulleys is controlled so as to generate a circumferential length difference between one belt edge and the other belt edge according to the difference value. With features That.

  A conveying device according to the present invention is a conveying device that conveys an article placed on or adsorbed on a belt driven by a pulley, and includes a belt adjusting device having the characteristics described in paragraphs 0008 to 0013. The belt running position can be adjusted by the belt adjusting device when the belt is driven.

  According to claim 1, since it is possible to detect the amount of displacement in the lateral direction relative to the lateral reference position of the belt at the same position in the circumferential direction of the belt, the edge portion structure of the belt can be detected. Further, it is possible to accurately detect the amount of displacement of the belt without being affected by dimensional errors in manufacturing. Also, since the arrangement of the pulleys is controlled so as to generate a circumferential length difference between one belt edge and the other belt edge based on the displacement, the displacement is out of the reference range due to the circumferential length difference. It is possible to correct the running position of the belt within the reference range.

  According to the second aspect of the present invention, the lateral displacement of the belt can be accurately determined at the same position in the circumferential direction of the belt without being affected by the edge structure of the belt or the manufacturing dimensional error. It becomes possible to detect. Here, the previously detected lateral displacement amount is stored as the first displacement amount, the lateral displacement amount detected after the belt has made a full turn is stored as the second displacement amount, and the first displacement amount is stored. Since the difference between the first displacement amount and the second displacement amount is calculated, it is possible to quantitatively grasp how much the belt is displaced in the lateral direction by the difference amount. As a result, since the arrangement of the pulleys is controlled so as to generate a circumferential length difference between one belt edge and the other belt edge based on the difference amount, the belt running position is determined by the circumferential length difference. Can be corrected toward a desired position.

  According to claim 3, the belt adjusting device according to claim 2 does not have to be used together with the belt adjusting device according to claim 1, and can be carried out alone.

  According to claim 4, when the belt is driven by the driving pulley and is located on the most flat surface traveling from the driven pulley to the driving pulley, the lateral displacement amount of the belt is detected, Controlling the arrangement of the driven pulley corresponding to the upstream side in the belt traveling direction at the time is effective for adjusting the belt position with high accuracy.

  According to claim 5, the belt lateral displacement amount is detected when the belt is driven by the drive pulley as described in the preceding paragraph and is on the surface running from the driven pulley toward the drive pulley, and the driven pulley In this case, it is effective to provide a detection sensor for detecting the amount of displacement relative to the lateral reference position of the belt immediately after the belt is sent out from the driven pulley. Since this information can be immediately reflected in the control of the driven pulley, it is effective in that the belt position is adjusted with high accuracy.

  According to the sixth aspect of the present invention, the rear displacement detection sensor is provided as another sensor for detecting the rearward displacement amount of the belt at a position behind the position where the displacement detection sensor is installed and ahead of the belt reaching the drive pulley. By providing, it is possible to monitor whether the lateral displacement of the belt is within the reference value at the position before the drive pulley enters under the situation where the belt position is adjusted by the front displacement detection sensor. Furthermore, the arrangement of the pulleys can be controlled so as to generate a circumferential length difference between one belt edge and the other belt edge based on the amount of rearward displacement. It becomes possible to correct the position toward the desired position.

  According to claim 7, by controlling the driven pulley to rotate in the same plane including the rotating shaft of the driving pulley and the rotating shaft of the driven pulley, with the horizontal intermediate point on the rotating shaft of the driven pulley as the center, It is possible to generate a difference in belt circumference necessary for correcting the belt running position to a desired lateral position.

According to claim 8, by detecting the amount of displacement in the lateral direction relative to the lateral reference position of the belt at the same position in the circumferential direction of the belt, the edge portion structure and manufacturing of the belt The belt displacement can be accurately detected without being affected by the above dimensional error. Also, by controlling the arrangement of the pulleys so as to generate a circumferential length difference between one belt edge and the other belt edge based on the displacement amount, the displacement is out of the reference range due to the circumferential length difference. It is possible to correct the running position of the belt within the reference range.
At the same time, the amount of displacement that is detected first is stored as the first amount of displacement, and the amount of displacement detected after the belt has made one turn is stored as the second amount of displacement. When the difference between the first displacement amount and the second displacement amount is calculated, it is possible to quantitatively grasp how much the belt is displaced in the lateral direction by the difference amount. By controlling the arrangement of the pulleys so as to generate a circumferential length difference between one belt edge and the other belt edge based on the difference amount, the belt running position is set to a desired position based on the circumferential length difference. It becomes possible to correct for

  According to claim 9, the conveying device according to the present invention is provided with the belt adjusting device having the characteristics described in paragraphs 0016 to 0022, and the conveying belt is driven by the pulley and is running. Thus, it is possible to convey the article placed or adsorbed while adjusting the running position by preventing the belt from meandering.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
FIG. 1 is a schematic diagram showing an example of a belt adjusting device 1 according to the first embodiment of the present invention. FIG. 2 is a schematic view of the belt adjusting device 1 as viewed from above. FIG. 3 is an explanatory diagram of a mechanism for controlling the arrangement of pulleys. FIG. 4 is a schematic view of the belt adjustment device 1 according to the second embodiment of the present invention as viewed from above.
FIG. 5 is a measurement diagram showing how the belt is adjusted when the belt adjusting method according to the present invention is carried out using the belt adjusting device according to the embodiment of the present invention.

  As shown in FIG. 1, the belt 2 is supported by a drive pulley 12 and a driven pulley 11 that are rotatably supported. By appropriately setting the distance between the driving pulley 12 and the driven pulley 11, tension is applied to the belt 2. In terms of design, each pulley is installed so that the rotation shaft of the drive pulley 12 and the rotation shaft of the driven pulley 11 are parallel to each other. The belt 2 is driven in the direction of arrow A with a driving force applied by the driving pulley 12.

Here, the drive pulley 12 is a pulley for applying a driving force to the belt 2. The driving pulley 12 is connected to a driving source 17 to generate a driving force. Here, the drive source 17 is an electric motor as an example.
When the belt 2 is made of steel or the like, the drive pulley 12 does not have a meshing mechanism such as providing a gear on the drive pulley 12 and providing a gear groove corresponding to the belt 2. Therefore, the driving force of the driving pulley 12 is transmitted to the belt 2 by the frictional force between the driving pulley 12 and the belt 2.

On the other hand, the driven pulley 11 is a pulley that does not drive itself but rotates by the frictional force with the belt 2 driven by the driving pulley 12 while supporting the belt 2 and applying tension.
In carrying out the present invention, the driven pulley 11 is not limited to the one having no driving force, and may be a pulley having a driving force for driving the belt together with the driving pulley 12.

  Both the driving pulley 12 and the driven pulley 11 do not have flanges at both ends. Therefore, if any one of the driving pulley 12 and the driven pulley 11 is improperly arranged, the belt 2 is displaced from the predetermined traveling position. As a result, the belt 2 may come off from the pulley, or the belt 2 may meander.

Reference numeral 13 denotes a displacement detection sensor. The displacement detection sensor 13 is provided above one of the belt edges 3a or 3b. The displacement detection sensor 13 detects the lateral displacement amount of the belt 2, that is, the displacement amount between the actual belt edge position and the design reference belt edge position perpendicular to the belt running direction. Is done.
Normally, the displacement detection point 18 at which the amount of displacement is detected is provided at the position of the belt edge 3a. However, the displacement detection point 18 is provided on the surface of the belt 2 other than the belt edges 3a and 3b. Alternatively, the difference between the design reference position and the actual running position may be detected to determine the lateral displacement amount of the belt.
When the driven pulley 11 is controlled as in this embodiment, it is effective to provide the displacement detection sensor 13 immediately after the belt 2 is fed out from the driven pulley 11.

The belt adjusting apparatus 1 according to the present invention includes detection means for detecting a circumferential reference position 14 which is a reference position in the direction in which the belt travels.
The detection method may be any method such as a contact method, an image processing method, and an electric method. In addition, when the drive source 17 is a stepping motor, it is also possible to detect the circumferential reference position 14 by counting the number of steps when the belt 2 rotates once.
The circumferential reference position 14 is detected every time the belt 2 circulates, and the lateral displacement amount of the belt 2 when the belt 2 is at that position is detected.
Normally, steel belts do not have the same width in all circumferential positions because of the structure, and also include manufacturing errors, and the edges are wavy. The detection accuracy was poor.
However, according to the present invention, since the displacement amount can be detected at the same circumferential reference position 14, the displacement amount of the belt 2 can be accurately determined without being affected by the edge portion structure of the belt 2 or manufacturing dimensional errors. It becomes possible to detect.
A plurality of circumferential reference positions 14 may be provided.

Further, the belt adjusting device 1 includes a pulley control mechanism 21 that controls the arrangement of the pulleys.
When the displacement amount with respect to the lateral reference position of the belt detected at the circumferential reference position 14 reaches a predetermined value, the pulley control mechanism 21 changes one belt edge and the other belt edge according to the displacement amount. The arrangement of the pulleys is controlled so as to cause a difference in circumference between the two (hereinafter, this control is referred to as “X control”).
As an example, when the belt 2 is a steel belt and is displaced by a certain amount or more in the direction B during traveling, the driven pulley 11 is rotated in the clockwise direction in FIG. As a result, the peripheral length of the edge 3a is increased, the peripheral length of the edge 3b is decreased, and the running direction of the belt 2 is corrected in the direction opposite to the B direction due to the difference in peripheral length. As an example, the rotation center 33 passes through the intersection of the driven pulley lateral center 31 and the driven pulley shaft center 32 and is set perpendicular to a plane including the rotation axis of the drive pulley and the rotation axis of the driven pulley. The
Here, in the case where the belt 2 is made of a material other than steel, the rotational direction of the driven pulley 11 may be corrected counterclockwise even when the displacement in the same direction B is the same. That is, the rotation direction and the rotation amount of the driven pulley 11 are appropriately set according to the material of the belt and the lateral displacement amount of the belt.
Usually, the driven pulley 11 is controlled. Note that the drive pulley 12 may be controlled in addition to the driven pulley 11 or in place of the driven pulley 11.

  The pulley control mechanism 21 is configured such that a linear motion motor 22 is connected to the driven pulley 11 via a link block 24 as shown in FIG. In this operation, when the rod 23 of the linear motor 22 pushes the link block 24 at the action point 27 of the link block 24, the driven pulley 11 connected to the reaction point 28 is pushed with 29 as the rotation fulcrum. The rotation fulcrum 29 is decentered closer to the reaction point 28 than the intermediate point between the action point 27 and the reaction point 28. Therefore, the pushing length of the driven pulley 11 is converted to a minute length compared to the pushing length of the linear motor 22, and the rotational resolution of the driven pulley 11 can be made fine. At the same time, the pushing force of the driven pulley 11 is amplified compared to the pushing force of the linear motor 22.

Subsequently, 15 is a storage / calculation unit. Here, the operation of the storage / calculation unit 15 is such that the circumferential reference position 14 is detected for each rotation of the belt, and the lateral displacement amount of the belt 2 when the belt 2 is at that position is detected by the displacement detection sensor 13. The detected displacement amount, the first detected lateral displacement amount is stored as the first displacement amount, and the detected lateral displacement amount after the belt has made one turn is stored as the second displacement amount. . Thereafter, the difference between the first displacement amount and the second displacement amount is calculated.
When the difference amount becomes a predetermined value, the driven pulley 11 is driven by the pulley control mechanism 21 so as to cause a circumferential length difference between one belt edge and the other belt edge according to the difference amount. (Hereinafter, this control is referred to as “Y control”).
Usually, the driven pulley 11 is controlled. The drive pulley 12 may be controlled in addition to the driven pulley 11 or in place of the driven pulley 11.
As an effect of the Y control based on the difference amount, if the lateral displacement amount is within the reference value, the X control based on the displacement amount is not normally performed. For example, during one round of the belt, If a sudden displacement occurs in which the displacement fluctuates from the lower limit of the reference value to the upper limit of the reference value at once, it is predicted that the displacement will subsequently deviate from the reference value. Rather than responding with X control after that, it is possible to immediately grasp such belt running disturbance and respond quickly with Y control. As a result, it is possible to adjust the belt position with higher accuracy and precision. And
Here, regarding the X control and the Y control, only one of them may be carried out for belt position adjustment, or they may be used in combination.

As described above, steel belts are usually not the same in width at all circumferential positions in the structure, and also include manufacturing errors, and the edges are wavy. In the displacement detection, the detection accuracy was poor. Therefore, in particular, the belt position adjustment is controlled with a desired high precision as the belt 2 is made of steel and the distance between the drive pulley 12 and the driven pulley 11 is narrower or the lateral width of the belt 2 is wider. It was considered difficult.
However, according to the present invention, the steel belt having a narrow interval between the drive pulley 12 and the driven pulley 11 and a wide lateral width is not affected by the edge structure or manufacturing dimensional error. As a result, it is possible to accurately detect the amount of displacement of the belt, and as a result, it has been possible to adjust the belt position with high accuracy, which has been considered difficult.
Here, FIG. 5 shows a measurement result in which the meandering belt converges with a precise adjustment of the circulating belt when X control and Y control are used together. From this figure, it can be seen that the position adjustment with respect to the lateral reference position of the belt is realized with very high accuracy.

FIG. 4 shows a belt adjusting device 1 according to the second embodiment of the present invention. Backward displacement detection for detecting the amount of displacement of the belt 2 with respect to the lateral reference position at a position behind the installation position of the displacement detection sensor 13 and ahead of the belt 2 reaching the drive pulley 12. A sensor 16 is provided. This displacement amount is referred to as a backward displacement amount.
The arrangement of the driven pulley 11 is controlled so as to generate a circumferential length difference between one belt edge and the other belt edge in accordance with the rearward displacement amount (hereinafter, this control is referred to as “Z control”). .
Usually, the driven pulley 11 is controlled. The drive pulley 12 may be controlled in addition to the driven pulley 11 or in place of the driven pulley 11.
The effect of the backward displacement detection sensor 16 is whether the lateral displacement of the belt is within the reference value at the position before the drive pulley 12 enters under the situation where the belt position is adjusted by X control or Y control. It is to monitor.
By performing Z control in addition to X control and Y control, it is possible to adjust the belt position with higher accuracy and precision.

  By using the belt adjusting device having the configuration described above as an example, the belt adjusting method according to the present invention can be carried out.

In addition, by including the belt adjusting device having the configuration described above, it is possible to implement the conveying device according to the present invention.
Here, the conveyance device can convey the article by placing it on the outer surface of the belt 2 in the loop shape and on the upper surface. Further, by providing a mechanism (not shown) that is provided between the driven pulley 11 and the drive pulley 12 and sucks articles to the outer surface of the belt 2 by the action of suction from the inside of the belt 2 that is in a loop shape. The articles can be adsorbed and conveyed on both the outer surface of the looped belt 2 and the upper surface, and the outer surface of the belt 2 and the lower surface.
The conveying device can adjust the traveling position by preventing the belt 2 from meandering under the condition where the belt 2 is traveling.

  As described above, the case where the belt 2 is a steel belt has been described as an example. However, the belt adjusting device, the belt adjusting method, and the conveying device including the belt adjusting device according to the present invention can be used for belts other than steel. Of course you can.

It is the schematic which shows the example of the belt adjustment apparatus which concerns on 1st embodiment of this invention. It is the schematic which looked at the belt adjustment apparatus shown in FIG. 1 from the upper surface. It is explanatory drawing of the mechanism which controls arrangement | positioning of the pulley shown in FIG. It is the schematic which shows the example of the belt adjustment apparatus which concerns on 2nd embodiment of this invention. It is a measurement figure which shows the mode of belt adjustment at the time of implementing the belt adjustment method which concerns on this invention using the belt adjustment apparatus which concerns on embodiment of this invention. It is the schematic which shows an example of the belt adjustment apparatus which concerns on the conventional embodiment.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Belt adjustment apparatus 2 Belt 3a, 3b Belt edge 11 Driven pulley 12 Drive pulley 13 Displacement detection sensor 14 Circumferential direction reference position 15 Memory | storage / calculation part 16 Backward displacement detection sensor 17 Drive source 18 Displacement detection point 21 Pulley control mechanism 22 Linear motion Motor 23 Rod 24 Link block 27 Action point 28 Reaction point 29 Rotation fulcrum 31 Driven pulley lateral center 32 Driven pulley shaft center 33 Rotation center 41 Conveyed goods

Claims (9)

In a belt adjustment device that adjusts the traveling position by preventing meandering of a belt that is driven by a pulley and conveys an article,
Position detecting means for detecting a reference position in the circumferential direction of the belt for each rotation of the belt;
A displacement detection sensor for detecting a displacement amount with respect to a lateral reference position of the belt at the circumferential reference position;
A belt adjustment comprising: a pulley control mechanism that controls the arrangement of the pulleys so as to cause a circumferential length difference between one belt edge and the other belt edge according to the displacement amount. apparatus. Storage means for storing the first detected displacement amount as the first displacement amount, and storing the first detected displacement amount as the second displacement amount;
An arithmetic means for calculating a difference between the first displacement amount and the second displacement amount;
A pulley control mechanism that controls the arrangement of the pulleys so as to generate a circumferential length difference between one belt edge and the other belt edge according to the difference value. Item 2. A belt adjusting device according to Item 1. In a belt adjustment device that adjusts the traveling position by preventing meandering of a belt that is driven by a pulley and conveys an article,
Position detecting means for detecting a reference position in the circumferential direction of the belt for each rotation of the belt;
A displacement detection sensor for detecting a displacement amount with respect to a lateral reference position of the belt at the circumferential reference position;
Storage means for storing the first detected displacement amount as the first displacement amount, and storing the first detected displacement amount as the second displacement amount;
An arithmetic means for calculating a difference between the first displacement amount and the second displacement amount;
A belt comprising a pulley control mechanism for controlling the arrangement of the pulleys so as to cause a difference in circumference between one belt edge and the other belt edge according to the difference value. Adjustment device. The belt adjusting device according to any one of claims 1 to 3, wherein the pulley whose arrangement is controlled by the pulley control mechanism is a driven pulley. The belt adjustment device according to any one of claims 1 to 4, wherein the displacement detection sensor is provided at a position immediately after the belt passes through the driven pulley. A rear displacement detection sensor for detecting a rear displacement amount of the belt is provided at a position behind the installation position of the displacement detection sensor and at a position ahead of the belt reaching the drive pulley.
A pulley control mechanism that controls the arrangement of the driven pulley so as to cause a circumferential length difference between one belt edge and the other belt edge according to the rearward displacement amount. Item 6. The belt adjusting device according to Item 5. The driven pulley rotates in the same plane including the rotating shaft of the driven pulley and the rotating shaft of the driven pulley, with the pulley control mechanism being centered on a lateral intermediate point on the rotating shaft of the driven pulley. The belt adjusting device according to claim 5, further comprising a pulley operating unit that controls an arrangement of the driven pulley so as to cause the circumference difference. In a belt adjustment method for adjusting a running position by preventing meandering of a belt driven by a pulley and conveying an article,
Detecting the circumferential reference position of the belt for each revolution of the belt,
Detecting a displacement amount with respect to a lateral reference position of the belt at the circumferential reference position;
According to the amount of displacement, controlling the arrangement of the pulleys so as to cause a circumferential length difference between one belt edge and the other belt edge,
The displacement amount, which is detected first is stored as a first displacement amount, and the displacement detected after one round of the belt is stored as a second displacement amount,
Calculating the difference between the first displacement amount and the second displacement amount;
A belt adjustment method, wherein the arrangement of the pulleys is controlled so as to generate a circumferential length difference between one belt edge and the other belt edge according to the difference value. A conveying device that conveys an article placed on or adsorbed to a belt driven by a pulley, comprising the belt adjusting device according to any one of claims 1 to 7, wherein the belt is driven when the belt is being driven. A conveyance device capable of adjusting a belt traveling position by a belt adjustment device.