Sensing method for start and stop of belt conveyor

Abstract

To provide a sensing method for the start and stop of a belt conveyor which is free from deterioration due to friction associated with an operation of the belt conveyor, does not require stopping the belt conveyor during installation and adjustment, and can safely detect the start and stop of the belt conveyor.SOLUTION: A sensing method for the start and stop of a belt conveyor senses the start and stop of the belt conveyor by at least one start and stop sensor selected from the group consisting of a vibration sensor and a sound sensor installed at a position not in contact with an operation part of the belt conveyor.SELECTED DRAWING: None

Description

[Technical field]

[0001] The present invention relates to a method for detecting the start and stop of a belt conveyor. [Background technology]

[0002] Conventionally, the following technologies have been used to detect the start and stop of belt conveyors: (1) Merrick-type belt scale (conveyor scale) (Non-patent document 1) (2) Roller Encoder (Rotary Encoder) (Non-Patent Document 2) (3) Current value of the belt conveyor motor [Prior art documents] [Non-patent literature]

[0003] [Non-Patent Document 1] Journal of the Japan Paper and Pulp Technology Association, Vol. 23, No. 4, pp. 36-43, "Easy Instrument Accounting for Field Operators (7)" https: / / www.jstage.jst.go.jp / article / jtappij1955 / 23 / 4 / 23_4_36 / _pdf [Non-Patent Document 2] Meritec Corporation website "What is an encoder?" https: / / e-meltec.jp / about-encorder Summary of the Invention [Problem to be solved by the invention]

[0004] Of the above-mentioned belt conveyor start / stop detection methods (1) to (3), (1) and (2) require contact between the belt conveyor and a start / stop sensor such as a belt scale or an encoder, and have a moving part that moves in accordance with the movement of the belt, which can lead to malfunctions due to corrosion or dust, and deterioration due to friction. In addition, it is complicated because it is necessary to adjust the degree of contact between the belt conveyor and the start / stop sensor. Furthermore, it is necessary to install and adjust the sensor while the belt conveyor is stopped, which requires the factory to stop operating. The above (3) is not suitable for monitoring because measuring the current value is dangerous.

[0005] The present invention aims to provide a method for detecting the start and stop of a conveyor belt, which is free of deterioration due to friction associated with the operation of the conveyor belt, does not require stopping the conveyor belt during installation and adjustment, and can safely detect the start and stop of the conveyor belt. [Means for solving the problem]

[0006] The present invention provides the following [1] to [3]. [1] A method for detecting the start and stop of a belt conveyor, comprising detecting the start and stop of the belt conveyor using at least one start / stop sensor selected from the group consisting of a vibration sensor and a sound sensor installed in a position not in contact with the moving part of the belt conveyor. [2] The method for starting and stopping a belt conveyor described in [1] above, further comprising a start / stop determination step for determining that the belt conveyor is stopped if the data obtained from the start / stop sensor is below a threshold value, and determining that the belt conveyor is operating if the data obtained from the start / stop sensor is above the threshold value. [3] The method for starting and stopping a belt conveyor described in [2] above, further comprising controlling operation of other equipment based on the result of the judgment in the start / stop judgment process. Effect of the Invention

[0007] According to the method for detecting the start / stop of a conveyor belt of the present invention, it is possible to provide a method for detecting the start / stop of a conveyor belt that is free of deterioration due to friction associated with the operation of the conveyor belt, does not require stopping the conveyor belt during installation and adjustment, and can safely detect the start / stop of the conveyor belt. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0008] A method for detecting start / stop of a conveyor belt according to the present invention will be described below. The method for detecting the start and stop of a belt conveyor according to the present invention is a method for detecting the start and stop of a belt conveyor, which detects the start and stop of the belt conveyor using at least one type of start and stop sensor selected from the group consisting of a vibration sensor and a sound sensor installed in a position not in contact with the moving part of the belt conveyor. Vibrations and sounds are generated when the belt conveyor is in operation, and no vibrations or sounds are generated when it is stopped. According to the present invention, the start and stop of the belt conveyor is detected by at least one start / stop sensor selected from the group consisting of a vibration sensor and a sound sensor, so that the start and stop of the belt conveyor can be detected reliably. Note that there are vibrations and sounds that are not caused by the belt conveyor around the start / stop sensor, but these surrounding vibrations and sounds are weaker than the vibrations and sounds caused by the target belt conveyor, so they can be distinguished. In addition, according to the present invention, the start / stop sensor does not come into contact with the moving part of the belt conveyor, so there is no deterioration due to friction caused by the operation of the belt conveyor, and there is no need to stop the belt conveyor during installation and adjustment. In addition, since the start / stop sensor does not measure the current value of the moving part of the belt conveyor, start / stop detection can be performed safely.

[0009] In the present invention, the start / stop sensor is preferably not installed on moving parts such as the belt, rollers, or pulleys of the belt conveyor, but is preferably installed, for example, on a casing of a motor or the like, a stand around a moving part, or on a walkway located near the belt conveyor. In particular, when the start / stop sensor is a sound sensor, it is preferable to install it near the motor, rollers, or other places where sound is generated. In addition, when there is a non-target belt conveyor around the target belt conveyor, it is preferable to install the sound sensor as close as possible to the target belt conveyor. The start / stop sensor may be attached to the equipment surrounding the belt conveyor with adhesive or screws. It may also be attached to a fence installed on the sidewalk around the belt conveyor to prevent contact with the belt conveyor. The start / stop sensor installed on a plate may also be attached to the equipment surrounding the belt conveyor or to a fence to prevent contact.

[0010] The sound sensor may be of any type, such as electrodynamic, electrostatic, or piezoelectric, but it is particularly preferable to use an electrostatic type, which is highly stable and can be made compact. Vibration sensors are classified into acceleration detection types, speed detection types, displacement detection types, etc., and any type may be used. Among these, acceleration detection types are particularly preferred. Examples of acceleration detection types include piezoelectric types, electrodynamic types, and strain gauge types, but the piezoelectric type is preferred because it can cover a wide frequency range.

[0011] In the present invention, it is preferable to have a start / stop determination step of determining that the belt conveyor is stopped if the data obtained from the start / stop sensor is below a threshold value, and determining that the belt conveyor is operating if the data is above the threshold value. By setting the threshold value in this manner, it is possible to reliably prevent the start / stop sensor from malfunctioning due to vibrations or sounds from equipment other than the target belt conveyor.

[0012] The data obtained by the start / stop sensor may be transmitted to a PC via wire or wirelessly. In the present invention, the operation of other equipment may be controlled based on the judgment result in the start / stop judgment process. For example, it may be used to control the turning on / off of a patrol lamp that notifies the BC operation status.

[0013] One or more start / stop sensors may be installed in a position that does not contact the moving parts of the belt conveyor. If one sensor is installed, costs can be reduced. If two or more sensors are installed, even if one of the multiple start / stop sensors breaks down, the start / stop of the belt conveyor can be continuously detected. When two or more start / stop sensors are installed, it is preferable to determine "start" when two or more sensors detect "start", and to determine "stop" when only one sensor detects "start" but the other sensor detects "stop". This prevents the start / stop sensor from making an erroneous judgment due to vibrations or sounds other than those of the target belt conveyor. In the case of a single start / stop sensor, it is preferable that the sensor detects sound or vibration multiple times at intervals within a specified period of time, and if "start" is detected multiple times, it is judged as "start", and if "start" is detected only once and "stop" is detected the remaining times, it is judged as "stop". Furthermore, regardless of the number of start / stop sensors, sound or vibration may be detected multiple times or continuously at intervals within a specified time, and "on" or "off" may be determined based on the average value over a certain period of time. This prevents the start / stop sensor from making an erroneous determination due to vibrations or sounds other than those of the target belt conveyor.

[0014] It is preferable to measure the frequency band of the vibration of the target belt conveyor, and determine that the start / stop sensor is "starting" when it detects the frequency band, and "stopping" when it does not detect the frequency band. This prevents the start / stop sensor from making an erroneous determination due to vibrations generated from sources other than the target belt conveyor. It is also preferable to measure the frequency band of the sound of the target belt conveyor, and determine that the start / stop sensor is "starting" when it detects the frequency band, and "stopping" when it does not detect the frequency band. This makes it possible to prevent the start / stop sensor from making an erroneous determination due to sounds emitted from sources other than the target belt conveyor.

[0015] It is preferable to measure the waveform pattern of the vibration of the target belt conveyor, and determine that the start / stop sensor is "starting" when it detects the waveform pattern, and "stopping" when it does not detect the waveform pattern. This makes it possible to prevent the start / stop sensor from making an erroneous determination due to vibrations generated from sources other than the target belt conveyor. It is also preferable to measure the waveform pattern of the sound of the target belt conveyor, and determine that the start / stop sensor is "starting" when it detects the waveform pattern, and "stopping" when it does not detect the waveform pattern. This makes it possible to prevent the start / stop sensor from making an erroneous determination due to sounds emitted from sources other than the target belt conveyor.

[0016] It is desirable to install the start / stop sensor in a location away from other operating equipment in order to reduce the influence of anything other than the target belt conveyor. In this case, it becomes easier to judge "start" and "stop". On the other hand, a start / stop sensor may be installed near a transfer point of the target belt conveyor. In this case, for example, the start and stop of the belt conveyor may be detected as follows. (1) Measure in advance the volume V1 when only the belt conveyor which has the lower volume during starting between the belt conveyor on the upstream side and the belt conveyor on the downstream side of the transfer section is in operation, the volume V2 when only the belt conveyor which has the higher volume during starting between the belt conveyor on the upstream side and the belt conveyor on the downstream side of the transfer section is in operation, and the volume V3 when both the belt conveyor on the upstream side and the belt conveyor on the downstream side of the transfer section are in operation. (2) The first threshold T1, the second threshold T2, the third threshold T3, and the fourth threshold T4 are set as follows. T1 <V1<T2<V2<T3<V3<T4 (3) When the start / stop sensor detects a sound less than the first threshold T1 or does not detect any sound, it determines that "both the belt conveyor with the lower volume and the belt conveyor with the higher volume are stopped," When the start / stop sensor detects a sound that is equal to or greater than the first threshold T1 and equal to or less than the second threshold T2, it determines that "only the belt conveyor with the lower volume is operating" (determined to be in an abnormal state), When the start / stop sensor detects a sound that exceeds the second threshold T2 and is equal to or lower than the third threshold T3, it determines that "only the belt conveyor with the louder sound is operating" (determined to be in an abnormal state), When the start / stop sensor detects a sound that exceeds the third threshold T3 and is equal to or lower than the fourth threshold T4, it determines that "both the belt conveyor with the quieter volume and the belt conveyor with the louder volume are operating."

[0017] A start / stop sensor may be installed near the transfer point of the target belt conveyor, and the start / stop of the belt conveyor may be detected as follows. (1) Measure in advance the volume V1 when only the belt conveyor which has the lower volume during starting between the belt conveyor on the upstream side and the belt conveyor on the downstream side of the transfer section is in operation, the volume V2 when only the belt conveyor which has the higher volume during starting between the belt conveyor on the upstream side and the belt conveyor on the downstream side of the transfer section is in operation, and the volume V3 when both the belt conveyor on the upstream side and the belt conveyor on the downstream side of the transfer section are in operation. (2A) The 1A threshold T1A, the 2A threshold T2A, and the 3A threshold T3A are set as follows. T1A <V1<V2<T2A<V3<T3A (3A) When the start / stop sensor detects a sound less than the first threshold T1 or does not detect any sound, it is determined that "both the belt conveyor with the lower volume and the belt conveyor with the higher volume are stopped," When the start / stop sensor detects a sound that is equal to or greater than the 1A threshold T1A and equal to or less than the 2A threshold T2A, it determines that "only one of the belt conveyors with the lower volume or the belt conveyor with the higher volume is operating" (determines that an abnormal state exists), When the start / stop sensor detects a sound that exceeds the second threshold T2A and is equal to or lower than the third threshold T3A, it determines that "both the belt conveyor with the quieter volume and the belt conveyor with the louder volume are operating."

[0018] A start / stop sensor may be installed near a transfer point of the target belt conveyor. In this case, for example, the start and stop of the belt conveyor may be detected as follows. (1) Measure in advance the vibration intensity S1 when only the belt conveyor having the smaller vibration intensity during starting between the belt conveyor on the upstream side and the belt conveyor on the downstream side of the transfer section is in operation, the vibration intensity S2 when only the belt conveyor having the larger vibration intensity during starting between the belt conveyor on the upstream side and the belt conveyor on the downstream side of the transfer section is in operation, and the vibration intensity S3 when both the belt conveyor on the upstream side and the belt conveyor on the downstream side of the transfer section are in operation. (2) The first threshold T1, the second threshold T2, the third threshold T3, and the fourth threshold T4 are set as follows. T1 <S1<T2<S2<T3<S3<T4 (3) When the start / stop sensor detects a vibration intensity less than the first threshold T1 or does not detect a sound, it determines that "both the belt conveyor with the lower vibration intensity and the belt conveyor with the higher vibration intensity are stopped," When the start / stop sensor detects a vibration intensity that is equal to or greater than the first threshold T1 and equal to or less than the second threshold T2, it determines that "only the belt conveyor with the smaller vibration intensity is operating" (determined to be in an abnormal state), When the start / stop sensor detects a vibration intensity that exceeds the second threshold T2 and is equal to or less than the third threshold T3, it determines that "only the belt conveyor with the greater vibration intensity is operating" (determined to be in an abnormal state), When the start / stop sensor detects a vibration intensity that exceeds the third threshold T3 and is equal to or less than the fourth threshold T4, it determines that "both the belt conveyor with the lower vibration intensity and the belt conveyor with the higher vibration intensity are operating."

[0019] A start / stop sensor may be installed near the transfer point of the target belt conveyor, and the start / stop of the belt conveyor may be detected as follows. (1) Measure in advance the vibration intensity S1 when only the belt conveyor having the smaller vibration intensity during starting between the belt conveyor on the upstream side and the belt conveyor on the downstream side of the transfer section is in operation, the vibration intensity S2 when only the belt conveyor having the larger vibration intensity during starting between the belt conveyor on the upstream side and the belt conveyor on the downstream side of the transfer section is in operation, and the vibration intensity S3 when both the belt conveyor on the upstream side and the belt conveyor on the downstream side of the transfer section are in operation. (2A) The 1A threshold T1A, the 2A threshold T2A, and the 3A threshold T3A are set as follows. T1A <s1<s2<t2a<s3<t3a(3A) When the start / stop sensor detects a vibration intensity less than the first threshold T1 or does not detect a vibration intensity, it is determined that "both the belt conveyor with the lower vibration intensity and the belt conveyor with the higher vibration intensity are stopped", When the start / stop sensor detects a vibration intensity that is equal to or greater than the first A threshold T1A and equal to or less than the second A threshold T2A, it determines that "only one of the belt conveyors with the lower vibration intensity and the belt conveyor with the higher vibration intensity is operating" (determines that an abnormal state exists), When the start / stop sensor detects a vibration intensity that exceeds the second threshold T2A and is equal to or lower than the third threshold T3A, it determines that "both the belt conveyor with the lower vibration intensity and the belt conveyor with the higher vibration intensity are operating."

Claims

1. A method for detecting start / stop of a belt conveyor, comprising detecting start / stop of the belt conveyor using at least one start / stop sensor selected from the group consisting of a vibration sensor and a sound sensor installed at a position not in contact with a moving part of the belt conveyor.

2. 2. The method for starting and stopping a belt conveyor according to claim 1, further comprising a start / stop determination step of determining that the belt conveyor is stopped if data obtained from the start / stop sensor is less than a threshold value, and determining that the belt conveyor is operating if data obtained from the start / stop sensor is equal to or greater than the threshold value.

3. The method for starting and stopping a belt conveyor according to claim 2, further comprising controlling operation of other equipment based on a result of the determination in the start / stop determination step.