Belt conveyor meandering correction device

Abstract

To provide a meandering correction device which can correct meandering of a belt conveyor in real time with a simple structure, and is applicable to all types of belt conveyors.SOLUTION: A meandering correction device comprises: temperature sensors for detecting temperature of a casing which accommodates, therein, an endless annular belt of a belt conveyor in a manner of covering a periphery of the endless annular belt; at least one pair of support means displaceably supporting respectively both axial end side of a rotation shaft of at least one pulley of a pair of pulleys which is disposed on inner peripheral sides of both ends in the longitudinal direction of the belt and rotatably supports the belt; and control means for variably controlling support positions of the rotary shaft supported by at least the pair of support means based on temperature information from the temperature sensor.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a meandering correction device for correcting meandering of a belt in a belt conveyor. [Background Art]

[0002] Conventionally, as a device for correcting meandering of a belt of a belt conveyor, there has been known a meandering correction device provided with a pair of correction rollers, which are in contact with a belt so as to sandwich the belt from above and below, and a pair of detection rollers, which are arranged on both sides of the belt and rotatable with respect to a swinging member that swings around a central axis perpendicular to the traveling direction of the belt (see, for example, Patent Document 1). [Prior Art Documents] [Patent Documents]

[0003] [Patent Document 1] Japanese Unexamined Patent Application Publication No. 2020-186085 [Summary of the Invention] [Problem to be Solved by the Invention]

[0004] However, in the meandering correction device of the prior art disclosed in the above Patent Document 1, when the detection roller on the side of the belt comes into contact with the belt, the swinging member swings, and the correction roller tilts around the central axis accordingly, thereby changing the position where the belt is sandwiched to correct the meandering. For this reason, there is a problem that the number of parts is large, the structure is complicated, and mechanical wear is likely to occur in relation to meandering correction. In addition, since it has a structure in which a pair of correction rollers are in contact with each other so as to sandwich the belt between the upper and lower sides, there is also a problem that it cannot be applied to a bucket-type belt conveyor.

[0005] The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a meandering correction device for a belt conveyor that can correct belt meandering in real time with a simple structure applicable to all types of belt conveyors. [Means for Solving the Problem]

[0006] The belt conveyor meandering correction device according to the present invention comprises: a temperature sensor unit for detecting the temperature of a casing housed inside so as to cover the circumference of the endless annular belt of the belt conveyor; at least one set of support means for displaceably supporting both axial ends of the rotation axis of at least one of a pair of pulleys arranged on the inner circumference side of both longitudinal ends of the belt and supporting the belt in a rotatable manner; and a control means for variably controlling the support position of the rotation axis by at least the pair of support means based on temperature information from the temperature sensor unit.

[0007] In one embodiment of the present invention, the temperature sensor units are provided on both ends of the belt in the short direction intersecting the longitudinal direction, and the control means determines the amount of displacement of the belt due to the temperature difference in the short direction of the casing based on the temperature information from the respective temperature sensor units, and controls at least one of the support means to vary the support position of the rotation shaft according to the determination result.

[0008] In another embodiment of the present invention, the system further includes a displacement detection sensor unit capable of detecting the actual displacement of the belt, and the control means varies the support position of the rotation shaft when at least one of the displacement of the belt based on the determination result and the actual displacement of the belt detected by the displacement detection sensor unit exceeds a predetermined value set in advance.

[0009] In yet another embodiment of the present invention, the displacement detection sensor is provided on both ends of the belt in the short direction intersecting the longitudinal direction.

[0010] In yet another embodiment of the present invention, the at least one set of support means includes a plurality of bearing portions that each pivotally support the axial ends of the rotating shaft and are slidable in the longitudinal direction along the slide guide of the casing, and a plurality of telescopic mechanism portions, each having one end attached to the casing and the other end connected to the plurality of bearing portions so as to be displaceable relative to each other.

[0011] In yet another embodiment of the present invention, the plurality of telescopic mechanisms consist of one of an air cylinder, a hydraulic cylinder, and an electrically operated ball screw. [Effects of the Invention]

[0012] According to the present invention, belt meandering can be corrected in real time with a simple structure applicable to all types of belt conveyors. [Brief explanation of the drawing]

[0013] [Figure 1] This is a schematic front view of a belt conveyor illustrating the configuration of a meandering correction device according to one embodiment of the present invention. [Figure 2] This is a schematic side view showing the overall appearance of a belt conveyor to which the meandering correction device has been applied. [Figure 3] This is an enlarged view of section A in Figure 2. [Figure 4] Figure 3 is an enlarged cross-sectional view of the BB line. [Figure 5] This flowchart shows an example of the procedure for correcting belt meandering using the same meandering correction device. [Figure 6] This is a schematic diagram illustrating how the belt's meandering is corrected by the meandering correction device. [Modes for carrying out the invention]

[0014] Hereinafter, a belt conveyor meandering correction device according to an embodiment of the present invention will be described in detail with reference to the attached drawings. However, the following embodiments are not intended to limit the invention according to each claim, and not all combinations of features described in the embodiments are necessarily essential to the solution of the invention. In addition, in the following embodiments, the same or corresponding components are denoted by the same reference numerals, and redundant descriptions are omitted. Furthermore, in the embodiments, the arrangement, scale, and dimensions of each component may be exaggerated or reduced and may not correspond to the actual components, and some components may be omitted from the description.

[0015] Figure 1 is a schematic front view of a belt conveyor illustrating the configuration of a meandering correction device according to one embodiment of the present invention. Figure 2 is a schematic side view illustrating the overall appearance of a belt conveyor to which the meandering correction device is applied. Figure 3 is an enlarged view of section A in Figure 2. Figure 4 is an enlarged cross-sectional view of line BB in Figure 3.

[0016] As shown in Figure 1, a meandering correction device 10 according to one embodiment of the present invention is applied to a belt conveyor 1 and automatically corrects the meandering of the belt 2 of the belt conveyor 1. The meandering correction device 10 may consist of, for example, a sensor unit 11, a control unit 12, and a support unit 13. In this explanation, the state shown in Figure 1 is considered the front view of the belt conveyor 1, the depth direction of the paper in Figure 1 is considered the front-to-back direction, and the lateral direction of the paper in Figure 1 is considered the left-to-right direction.

[0017] The sensor unit 11 includes, for example, a pair of temperature sensors 14 and 15 and a pair of displacement detection sensors 16 and 17. Each of the sensors 14 to 17 is provided, for example, on both ends of the belt 2 in the short direction intersecting the longitudinal direction. The pair of temperature sensors 14 and 15 are provided on the outer wall portion 5b of the casing 5 at both ends of the belt 2 in the short direction. The pair of temperature sensors 14 and 15 each detect the temperature at the outer wall portion 5b of the casing 5 to which they are attached.

[0018] The pair of displacement detection sensors 16 and 17 are attached to the outer wall 5b of the casing 5 at both end sides in the widthwise direction of the belt 2. The pair of displacement detection sensors 16 and 17 penetrate the outer wall 5b of the casing 5 and face the internal space, and respectively detect, for example in a non-contact manner, the actual position of the side end of the belt 2 on the inner wall 5a side. Note that the displacement detection sensors 16 and 17 may be of a type that detects the actual position of the side end of the belt 2 by contact.

[0019] The control unit 12 is composed of devices such as an arithmetic processing unit and a personal computer (PC), and controls the operation of the support unit 13 based on detection signals from the sensor unit 11. The control unit 12 stores, for example, data indicating the degree of distortion related to temperature information of the casing 5. In addition, the control unit 12 stores various preset data (including threshold values, etc.) that define criteria for determining the displacement amount, such as how much the belt 2 is displaced and meanders depending on the degree of distortion of the casing 5 caused by temperature, and what degree of displacement is allowable.

[0020] The support unit 13 supports the tail pulley 4, which is at least one of a pair of pulleys that rotatably supports the belt 2 of the belt conveyor 1. The support unit 13 includes, for example, left and right pulley support mechanisms 20 and 30 that are at least one set of support means provided on both sides in the widthwise direction of the belt 2. Details of the meandering correction device 10 configured as described above will be described later.

[0021] The belt conveyor 1 to which the meandering correction device 10 is applied is a so-called bucket-type belt conveyor as shown in FIGS. 2 to 4, but is not limited thereto. The belt conveyor 1 is arranged, for example, outdoors, and is configured to include an endless annular belt 2, a plurality of bucket units 9 attached to the belt 2, the head pulley 3 and the tail pulley 4 as said pair of pulleys, and a casing 5.

[0022] The belt 2 is positioned so that its longitudinal direction is vertical. Multiple bucket sections 9 are arranged in multiples (for example, 3) along the short direction of the belt 2, and also at predetermined intervals along the longitudinal direction. The head pulley 3 and tail pulley 4 are positioned on the inner circumference of both ends of the belt 2 in the longitudinal direction.

[0023] The casing 5 covers the belt 2 to which multiple bucket sections 9 are attached and houses the belt conveyor 1 inside, functioning as the enclosure for the belt conveyor 1. The casing 5 is made of, for example, a cylindrical metal member with a rectangular horizontal cross-section. The casing 5 is provided with a head-side casing 6f on the upper head pulley 3 side, which houses a drive mechanism such as a motor that rotates the head pulley 3, and a workbench 6g for opening and closing an inspection door 6e on the rear side of the head pulley 3 to perform inspection work. The casing 5 is also provided with an inspection door 6b on the lower tail pulley 4 side, which opens and closes an inspection opening 6a on the front side, and multiple opening and closing doors 6d, 6d for opening and closing multiple discharge ports 6c, 6c near the bottom.

[0024] The head pulley 3 is driven by a drive mechanism to rotate the belt 2 in a circular motion, with both axial ends of its central rotating shaft 3a supported by fixed bearing portions 3b. The tail pulley 4 is positioned with both axial ends of its central rotating shaft 4a supported by pulley support mechanisms 20 and 30, respectively, so as to be displaceable. The belt 2 is guided by a guide roller mechanism 8 provided near the tail pulley 4 inside the casing 5 to maintain a predetermined tension between the head pulley 3 and the tail pulley 4 while circulating.

[0025] In a belt conveyor 1 configured in this way, for example, thermal expansion under direct sunlight outdoors can cause distortion in the casing 5, resulting in meandering of the belt 2 that travels around inside. In such cases, the meandering correction device 10 corrects the meandering of the belt 2 by, for example, displacing the rotation axis 4a of the tail pulley 4 in accordance with the amount of displacement of the belt 2 due to the deformation of the casing 5 caused by thermal expansion distortion. The meandering correction device 10 is configured to displace the rotation axis 4a by individually operating the left and right pulley support mechanisms 20 and 30 on both sides of the rotation axis 4a based on detection signals from the sensor unit 11, so that the meandering of the belt 2 can be detected immediately and corrected more precisely and accurately in real time.

[0026] In other words, the temperature sensors 14 and 15 of the sensor unit 11 are provided to detect, for example, the temperature of the left and right outer walls 5b of the casing 5. In the illustrated example, the temperature sensors 14 and 15 are provided at the ends of the short direction intersecting the longitudinal direction of the belt 2, near the center of the longitudinal direction of the casing 5, but are not limited to this. The temperature sensors 14 and 15 may also be provided on the inner wall 5a of the casing 5.

[0027] Each pair of pulley support mechanisms 20 and 30 is provided on the left and right outer wall portions 5b of the casing 5 near the tail pulley 4. Each pair of pulley support mechanisms 20 and 30 includes bearing portions 27 and 37 and left and right telescopic mechanism portions. The bearing portions 27 and 37 include rolling / sliding type bearings (e.g., spherical plain bearings) so that the rotation axis 4a of the tail pulley 4 can swing from side to side. The bearing portions 27 and 37 pivotally support both axial ends of the rotation axis 4a of the tail pulley 4.

[0028] The left and right telescopic mechanisms are, for example, electrically operated ball screws, one end of which is attached to the outer wall portion 5b of the casing 5, and the other end of which is connected to the bearing portions 27 and 37 so as to be relatively displaceable. The telescopic mechanisms may be constructed together with the electrically operated ball screws, or in place of the electrically operated ball screws, by telescopic structures such as air cylinders and hydraulic cylinders.

[0029] In other words, the telescopic mechanism includes drive motors 21 and 31, drive belts 22 and 32, screw shaft drive units 23 and 33, and screw shafts 24 and 34, respectively. The drive motors 21 and 31 and the screw shaft drive units 23 and 33 are attached to the outer wall 5b of the casing 5 via mounting plates 25 and 35.

[0030] The screw shaft drive units 23, 33 include screw shaft drive nut units 22b, 32b integrally provided with rotors 22a, 32a rotated by drive belts 22, 32, and upper and lower support units 23a, 33a that rotatably support the screw shaft drive nut units 22b, 32b via bearings 23b, 33b. The lower ends of the screw shafts 24, 34 are connected to bearing units 27, 37.

[0031] The bearing portions 27 and 37 are integrally formed with slider portions 26 and 36 that are slidable in the vertical direction. The slider portions 26 and 36 slide vertically between a pair of slide guide members 5c that extend vertically and are provided on the outer wall portion 5b of the casing 5. Together with the slider portions 26 and 36, the bearing portions 27 and 37 are displaced vertically at both axial ends of the rotating shaft 4a along the axial movement hole 5d that is formed to extend vertically between the slide guide members 5c. Since various known structures can be used for the above-described telescopic mechanism, a detailed explanation is omitted here.

[0032] With the telescopic mechanism configured in this way, the rotational drive by the drive motors 21 and 31 causes the rotors 22a and 32a and the screw shaft drive nut portions 22b and 32b to move the screw shafts 24 and 34 up and down via the drive belts 22 and 32, causing the bearing portions 27 and 37 to be displaced up and down. As a result, the rotation axis 4a of the tail pulley 4 is swung from side to side and tilted.

[0033] In the meandering correction device 10 configured in this way, for example, the control unit 12 determines the left-right distortion of the casing 5 based on the temperature difference derived from temperature information from temperature sensors 14 and 15, and also determines the amount of displacement of the belt 2 due to this distortion. If the amount of displacement of the belt 2 is such that meandering correction is necessary, the control unit 12 controls the expansion and contraction mechanisms of the pulley support mechanisms 20 and 30 based on information that defines the degree of oscillation of the rotating shaft 4a in relation to the distortion of the casing 5 included in the various data, and displaces the rotating shaft 4a so that the oscillation cancels out the meandering.

[0034] The meandering correction device 10 may be configured to determine the amount of belt 2 displacement using only the detection information from the displacement detection sensors 16 and 17. However, it is preferable to determine the amount of belt 2 displacement by combining the temperature sensors 14 and 15 with the displacement detection sensors 16 and 17. In this way, it is possible to determine the amount of belt 2 displacement in more detail and linearly compared to using only temperature information.

[0035] Figure 5 is a flowchart illustrating an example of the belt meandering correction procedure using a meandering correction device. Figure 6 is a schematic diagram illustrating how the belt meandering is corrected by the same meandering correction device. As shown in Figure 5, when the meandering correction process is started, the control unit 12 detects the temperature of the left and right sides of the casing 5 based on temperature information from temperature sensors 14 and 15 (step S100). Next, the control unit 12 determines the strain state of the casing 5 based on, for example, the temperature difference between the left and right sides of the casing 5, and determines the amount of displacement of the belt 2 on the left and right sides based on this (step S101).

[0036] Next, it is determined whether the amount of displacement of the belt 2 on the left and right sides is sufficient to correct the meandering (step S102). If it is determined that the amount of displacement of the belt 2 on the left and right sides is sufficient to correct the meandering (Yes in step S102), the actual amount of displacement of the belt 2 on the left and right sides (actual displacement) is detected based on the detection signals from the displacement detection sensors 16 and 17 (step S103).

[0037] Then, the control unit 12 determines whether the detected actual displacement of the belt 2 on the left and right sides is greater than or equal to a predetermined threshold (step S104). If it determines that the actual displacement is greater than or equal to a predetermined threshold (Yes in step S104), the control unit 12 calculates the amount of movement required for the left and right bearing sections 27 and 37 to correct the meandering that occurs in the expansion and contraction mechanism of the pulley support mechanisms 20 and 30 in accordance with the displacement of the belt 2, and performs control to change the support position of the rotation axis 4a of the tail pulley 4 by sending a drive signal to the drive motors 21 and 31 (step S105).

[0038] The predetermined threshold is used to determine, for example, that even if the temperature difference between the left and right sides of the casing 5 is greater than a predetermined value and it is judged that the belt 2 has been displaced to the extent that meandering correction is necessary, the actual amount of displacement of the belt 2 may not be sufficient to require meandering correction.

[0039] Once the support position of the rotating shaft 4a has been changed, a decision is made (step S106) to terminate the meandering correction operation according to a termination command issued by the operator via a button. If it is determined that the operation should not be terminated (No. in step S106), the process proceeds to step S100 and the subsequent processing is repeated.

[0040] On the other hand, if it is determined that the operation will be terminated (Yes in step S106), if it is determined in step S102 that the meandering correction is not necessary (No in step S102), or if it is determined in step S104 that the actual displacement is below a predetermined threshold (No in step S104), the series of meandering correction processes according to this flowchart will be terminated. In this way, it is possible to correct the meandering of the belt in real time with a simple structure.

[0041] It should be noted that the meandering correction process shown in the flowchart above is merely one example. For example, it is also possible to configure the system to perform meandering correction only when it is determined that the temperature detection of the casing 5 and the displacement detection of the belt 2 are performed in parallel, and the meandering correction is performed when it is determined that the result of either detection is sufficient. Alternatively, the system could be configured to constantly monitor the actual displacement of the belt 2, and when it is determined that the actual displacement is sufficient to require meandering correction, the degree of strain based on the temperature difference of the casing 5 is determined, and these factors are taken into consideration when performing meandering correction.

[0042] In step S105 above, the change in the support position of the rotation axis 4a of the tail pulley 4 is, for example, as shown in Figure 6, when it is determined that the belt 2 has meandered to the left of the casing 5, the bearing portion 27 of the pulley support mechanism 20 is moved downward from the casing 5 as indicated by the arrow in the figure, and the bearing portion 37 of the pulley support mechanism 30 is moved upward from the casing 5 as indicated by the arrow in the figure. This displaces the belt 2 as shown by the dashed line in the figure, correcting the meandering. If it is determined that the belt 2 has meandered to the right of the casing 5, the opposite control should be applied to the pulley support mechanisms 20 and 30.

[0043] In the above embodiment, a vertically arranged bucket-type belt conveyor was used as an example of the belt conveyor 1, but the invention is not limited to this, and the meandering correction device 10 can also be applied to a horizontally arranged conventional belt conveyor. Thus, the meandering correction device 10 of this embodiment is applicable to all types of belt conveyors and allows for real-time correction of belt meandering with a simple structure.

[0044] Although embodiments of the present invention have been described above, these embodiments are presented as examples and are not intended to limit the scope of the invention. These novel embodiments can be implemented in various other forms, and various omissions, substitutions, and modifications can be made without departing from the spirit of the invention. These embodiments and their variations are included in the scope and spirit of the invention, as well as in the claims of the invention and its equivalents. [Explanation of symbols]

[0045] 1 Belt conveyor 2 belts 3 Head Pulley 3a, 4a Rotation axis 5. Casing 5a Inner wall 5b Exterior wall 10. Meandering correction device 11 Sensor section 12 Control Unit 13 Support part 14,15 Temperature sensor 16,17 Displacement detection sensor 20,30 Pulley support mechanism

Claims

1. A temperature sensor unit that detects the temperature of a casing housed inside the endlessly ring-shaped belt of a belt conveyor, At least one set of support means that displaceably support the axial ends of the rotation axis of at least one of a pair of pulleys, which are arranged on the inner circumference side of both longitudinal ends of the belt and support the belt so as to be rotatable, A control means for variably controlling the support position of the rotating shaft by at least the pair of support means based on temperature information from the temperature sensor unit, Equipped with A device to correct the meandering of a conveyor belt.

2. The temperature sensor section is provided on both ends of the belt in the short direction intersecting the longitudinal direction. The control means determines the amount of belt displacement due to the temperature difference in the shorter direction of the casing based on the temperature information from the respective temperature sensor units, and controls at least one of the support means to vary the support position of the rotation shaft according to the determination result. A belt conveyor meandering correction device according to claim 1.

3. The system further includes a displacement detection sensor unit capable of detecting the actual displacement of the belt, The control means adjusts the support position of the rotation shaft when at least one of the amount of belt displacement based on the judgment result and the actual amount of belt displacement detected by the displacement detection sensor unit exceeds a predetermined value set in advance. A belt conveyor meandering correction device according to claim 2.

4. The displacement detection sensor unit is provided on both ends of the belt in the short direction intersecting the longitudinal direction. A belt conveyor meandering correction device according to claim 3.

5. The at least one set of support means is Multiple bearing portions that support both axial ends of the rotating shaft and are slidable in the longitudinal direction along the slide guide of the casing, It includes a plurality of telescopic mechanism parts, each having one end attached to the casing and the other end connected to the plurality of bearing parts in a manner that allows for relative displacement. A belt conveyor meandering correction device according to any one of claims 1 to 4.

6. The aforementioned multiple telescopic mechanisms consist of one of an air cylinder, a hydraulic cylinder, and an electrically operated ball screw. A device for correcting the meandering of a belt conveyor according to claim 5.

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