Belt conveyor stopping device and abnormal location detection system

Abstract

To provide a belt conveyor stopping device capable of detecting an abnormal part of a belt conveyor and an abnormal part detection system equipped with the same.SOLUTION: A belt conveyor stopping device of the present invention is a device for stopping a belt conveyor in operation, and is equipped with a "towline switch" having a towline and a "detection light" outputting visible light. Among these, the towline switch stops the belt conveyor when the towline is pulled, and the detection light connected to the towline switch outputs visible light when the towline switch stops the belt conveyor.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to a belt conveyor for sending slip generated by tunnel excavation to the portal side. More specifically, it relates to a belt conveyor stop device capable of detecting an abnormal location when an abnormality occurs in the belt conveyor and an abnormal location detection system equipped with the same.

Background Art

[0002] It is said that approximately two-thirds of the land in our country is mountainous. Therefore, roads, railways, etc. (hereinafter referred to as "roads, etc.") necessarily have sections passing through mountainous areas. In order to construct roads, etc. in this mountainous area, it is common to adopt either an excavation method that excavates a part of the slope or a tunnel method that drills through the ground. The tunnel method generally has a tendency for the construction cost per unit length (construction cost per unit length of roads, etc.) to be higher than that of the excavation method. On the other hand, it has a tendency for the amount of excavated soil (i.e., the amount of waste soil) to be less than that of the excavation method, and it also has the feature that the degree of freedom in the linear planning of roads, etc. is high (for example, it can take shortcuts). It is said that the number of tunnels constructed in the country so far exceeds 10,000.

[0003] As a construction method for mountain tunnels, until the 1970s, the "lagging method" that combined steel arch supports with wooden laggings to support the ground was the mainstream. Currently, however, NATM (New Austrian Tunneling Method) that actively utilizes the strength of the ground has become the mainstream. The main feature of NATM is the design concept that expects the strength (arch effect) possessed by the ground. Therefore, compared with the conventional lagging method, the scale of tunnel support work can be reduced, and moreover, the construction speed can be increased, so the construction cost can be reduced.

[0004] Furthermore, since the full-scale implementation of NATM in Japan, excavation technology has advanced dramatically, and various auxiliary methods have been developed to accommodate various types of ground conditions. In addition, mechanical excavation has become an option in addition to blasting excavation. There are also several methods for transporting the rock fragments (rock mass broken into smaller pieces by blasting) and soil (hereinafter collectively referred to as "spoils") generated by blasting excavation out of the mine. These include the "tire type," which transports the spoil by loading it onto dump trucks, the "rail type," which transports the spoil using rails laid inside the mine, and the "belt conveyor type," which transports the spoil using a continuous belt conveyor system installed inside the mine.

[0005] Of these methods, belt conveyor type spoil transport generally requires the installation of equipment for the entire length of the tunnel (excavation length), but it can be carried out in parallel with other processes (e.g., concrete spraying), thus shortening the excavation cycle. Furthermore, it does not use fossil fuels like dump trucks, so it does not have a negative impact on the environment (especially the underground environment), and it is more economically advantageous than other methods when the excavation length is long. For these reasons, belt conveyor type spoil transport tends to be adopted for relatively long tunnels such as those for Shinkansen (e.g., the Chuo Shinkansen maglev line) and expressways.

[0006] Typically, a continuous belt conveyor system consists of a belt conveyor, a mobile crusher, a tailpiece trolley, a belt storage device, a main drive device, etc. This belt conveyor is an endless belt that circulates between a head pulley on the mine entrance side and a tail pulley (tailpiece trolley) on the working face side; in other words, the head pulley and tail pulley function as reversal points for the endless belt. More specifically, at the head pulley on the mine entrance side, the endless belt moves from the top surface to the bottom surface and reverses from movement towards the mine entrance to movement towards the working face, and at the tail pulley on the working face side, the endless belt moves from the bottom surface to the top surface and reverses from movement towards the working face to movement towards the mine entrance. As a result, the spoil placed on the top surface of the endless belt is transported to near the mine entrance.

[0007] Blasting only breaks the bedrock into relatively large chunks, and this mass cannot be transported by a belt conveyor in this state. Therefore, a mobile crusher further crushes the rock mass generated by blasting into smaller pieces. The crushed rock (spoil) is then fed into the spoil input section (input hopper) of the tailpiece trolley and then placed on a belt conveyor to be transported towards the tunnel entrance. The tailpiece trolley is equipped with self-propelled means such as crawlers or tires, and can move (advance) as the tunnel face progresses. As the tailpiece trolley moves forward, the belt conveyor is pulled, and the belts stored in the belt storage device are sequentially unfurled to extend the belt conveyor.

[0008] Incidentally, in continuous belt conveyor systems, depending on the horizontal alignment of the deployed endless belt or the condition of the load (i.e., the spoil), the endless belt may approach one of the frames, a phenomenon known as "deviation" or "swerving." If this deviation is significant, it can make normal spoil transport difficult, such as causing the load to spill due to the tilt of the endless belt or damaging the endless belt by contact with the frame. Furthermore, it can even lead to industrial accidents, such as injuries to workers.

[0009] Therefore, the "Industrial Safety and Health Regulations" mandate the installation of emergency pull-cord switches on belt conveyors. An emergency pull-cord switch stops the belt conveyor when the pull-cord is pulled, thus preventing industrial accidents by emergency stopping the belt conveyor in the event of an accident. In conventional technologies such as Patent Document 1, the operating status of the emergency pull-cord switch was monitored using a control panel installed outside the mine. [Prior art documents] [Patent Documents]

[0010] [Patent Document 1] Japanese Patent Publication No. 2018-21363 [Overview of the project] [Problems that the invention aims to solve]

[0011] Emergency pull-out switches are placed along the belt conveyor at predetermined intervals. Therefore, when applied to long-distance tunnels, a large number of emergency pull-out switches will be installed. Furthermore, the pull-out cords of the emergency pull-out switches may be pulled by workers at their own discretion, or they may be pulled by falling material (in the case of tunnels, spoil). When the belt conveyor makes an emergency stop, it is necessary to identify the location of the abnormality, and therefore it is necessary to identify which emergency pull-out switch was activated. Of course, when a worker pulls the cord, the location of the abnormality can be identified, but when the cord is pulled due to falling spoil, the location of the abnormality cannot be identified immediately. Traditionally, when the cord was pulled by someone other than a worker, the only way to check was to check it at a control panel outside the tunnel or via a network built inside the tunnel.

[0012] However, conventional verification methods, namely those using control panels and underground networks, only indicate the approximate location of the activated emergency pull-out switch and cannot pinpoint the exact location of the malfunction. Therefore, in practice, workers rely on the approximate location obtained from control panels, etc., to travel to the site and search for the activated emergency pull-out switch. While it is true that an activated emergency pull-out switch can be visually identified by a change in the orientation of its hook, as shown in Figure 6 (especially the arrows), the change is minute, and detecting the hook orientation in the dusty underground environment is not easy. In particular, in recent years, there has been a trend to place belt conveyors at relatively high positions to make effective use of underground space, making it even more difficult to detect changes in the emergency pull-out switch (Figure 6).

[0013] The object of the present invention is to solve the problems of the prior art, namely, to provide a belt conveyor stopping device that can detect abnormal locations on a belt conveyor and an abnormal location detection system equipped therewith. [Means for solving the problem]

[0014] The present invention focuses on the fact that when a pull-cord switch is activated to stop a belt conveyor, a detection lamp associated with the pull-cord switch outputs visible light, and is an invention based on a completely new idea.

[0015] The belt conveyor stopping device of the present invention is a device for stopping a belt conveyor in operation, and is equipped with a "pull rope switch" having a pull rope and a "detection lamp" that emits visible light. The pull rope switch stops the belt conveyor when the pull rope is pulled, and the detection lamp connected to the pull rope switch emits visible light when the pull rope switch stops the belt conveyor.

[0016] The belt conveyor stopping device of the present invention may also be configured such that the pull rope switch has a "contact changeover switch" and two or more "cable contacts". In this case, the two "lighting cables" connected to the detection lamp are each connected to different cable contacts. When the pull rope is pulled, the contact changeover switch connects the cable contacts to which the lighting cables are connected, causing the detection lamp to emit visible light as an electric current is generated.

[0017] The belt conveyor stopping device of the present invention may also be equipped with a portable detection light. In this case, the detection light is attached to two detachable lighting cables. The detection light, when removed from the lighting cables, emits visible light when the power is operated.

[0018] The abnormal location detection system of the present invention is a system for detecting abnormal locations on a belt conveyor using the belt conveyor stopping device of the present invention, and comprises a belt conveyor and a belt conveyor stopping device. The belt conveyor stopping devices are installed at multiple locations along the belt at intervals. The abnormal location on the belt conveyor can be detected by the output of visible light from a detection lamp associated with the pull rope switch that stops the belt conveyor. [Effects of the Invention]

[0019] The belt conveyor stopping device and the abnormal location detection system of the present invention have the following effects. (1) It can be installed retrospectively not only for a newly established (i.e., a tunnel where excavation is about to start) continuous belt conveyor system but also for an existing (i.e., an operating) continuous belt conveyor system. (2) By making the detection lamp portable, as a result, flashlights will be arranged at regular intervals. Therefore, this detection lamp can be effectively utilized when the lighting in the mine is interrupted. (3) The detection lamp used as a flashlight can be battery-powered. Therefore, wiring facilities for the detection lamp are unnecessary, and there are no special restrictions on its installation location. That is, it can be easily placed in the mine without any particular obstacles.

Brief Description of the Drawings

[0020] [Figure 1] Tunnel cross-sectional view schematically showing the belt conveyor stopping device of the present invention. [Figure 2] (a) Side view schematically showing a detection lamp connected to a draw rope switch via a lighting cable, (b) Partial side view schematically showing a lighting cable detachably connected by a connecting fixture. [Figure 3] Side view schematically showing a draw rope switch and a detection lamp connected by a lighting cable composed of a lower cable, an upper cable, and an intermediate cable. [Figure 4] (a) Model diagram schematically showing a situation where electricity is flowing through the draw rope switch, (b) Model diagram schematically showing a situation where no electricity is flowing through the draw rope switch. [Figure 5] Side view schematically showing the abnormal location detection system of the present invention. [Figure 6] Side view schematically showing an emergency draw rope switch actuated by pulling the draw rope.

Embodiments for Carrying out the Invention

[0021] Examples of the implementation of the belt conveyor stopping device and abnormal location detection system of the present invention will be explained with reference to the figures. The present invention can be applied to various places and facilities that use continuous belt conveyor systems, such as earthwork sites and quarries that transport soil and crushed rock, factories that manufacture products on a line, and logistics centers that sort delivered goods. It can also be applied to ordinary belts (belts that are not endless) as well as endless belts, but for convenience, an example of its application to a continuous belt conveyor system (endless belt) used for transporting spoil in tunnel excavation will be explained here.

[0022] 1. Belt conveyor stopping device The belt conveyor stopping device of the present invention will be described with reference to the figures. The abnormal location detection system of the present invention consists of belt conveyor stopping devices arranged at multiple locations along the belt conveyor 200. Therefore, the belt conveyor stopping device of the present invention will be described first, and then the abnormal location detection system of the present invention will be described.

[0023] Figure 1 is a schematic diagram of the belt conveyor stopping device 100 of the present invention, and is a cross-sectional view of a tunnel cut in a vertical plane. As shown in this figure, the belt conveyor stopping device 100 of the present invention is configured to include a pull rope switch 110 and a detection light 120, and may also be configured to include a lighting cable 130.

[0024] The following will provide a detailed explanation of each of the main elements that constitute the belt conveyor stopping device 100 of the present invention.

[0025] (Tug rope switch) As previously described, the pull rope switch 110 stops the belt conveyor 200 when its pull rope is pulled. Therefore, the pull rope switch 110 is positioned to the side of the belt conveyor 200. For example, in Figure 1, the belt conveyor 200, which constitutes a continuous belt conveyor system, is installed on a belt conveyor frame MB, and the pull rope switch 110 is also installed on this belt conveyor frame MB to the side of the belt conveyor 200. When adjusting the installation height of the pull rope switch 110, it is also possible to install the pull rope switch 110 on a pull rope switch frame MS, as shown in Figure 1.

[0026] The pull rope switch 110 used in the belt conveyor stopping device 100 of the present invention can be manufactured as a dedicated component, or a conventional general-purpose emergency pull rope switch can be used. Generally, emergency pull rope switches are broadly classified into manual reset type and automatic reset type, but both can be used as the pull rope switch 110.

[0027] (Detection light) The detection light 120 emits visible light when the pull rope switch 110 is activated, that is, when the belt conveyor 200 is stopped. Therefore, the detection light 120 is connected to the pull rope switch 110 via the lighting cable 130, as shown in Figure 2(a). The detection light 120 can also be installed on a detection light stand MF attached to the tunnel lining concrete LC (usually secondary sprayed concrete), as shown in Figure 1. In this case, it is preferable to position the detection light stand MF (i.e., the detection light 120) below the belt conveyor 200 at a height that is within reach of a person.

[0028] If the detection light 120 is positioned within reach of a person, and the pull-cord switch 110 (i.e., the belt conveyor 200) is positioned relatively high, then a lighting cable 130 of considerable length is required. In this case, the pull-cord switch 110 and the detection light 120 can be connected with a single continuous lighting cable 130, or they can be connected using an intermediate cable. Specifically, as shown in Figure 3, the lighting cable 130 is composed of a lower cable 131, an upper cable 132, and an intermediate cable 133. One end of the lower cable 131 is connected to the detection light 120, and one end of the upper cable 132 is connected to the pull-cord switch 110. The other ends of the lower cable 131 and the upper cable 132 are then connected to the ends of the intermediate cable 133, respectively.

[0029] To connect lighting cables 130 together (for example, the lower cable 131 and the intermediate cable 133), it is advisable to use a connecting jig CN as shown in Figure 2(b). The connecting jig CN shown in this figure consists of a concave jig CNa and a convex jig CNb, and the two are connected by inserting a part of the convex jig CNb into the concave jig CNa, meaning that the lighting cables 130 can be connected to each other in a detachable manner. For example, by attaching the concave jig CNa to the end of the lower cable 131 and the convex jig CNb to the end of the intermediate cable 133, and then connecting the convex jig CNb and the concave jig CNa, the lower cable 131 and the intermediate cable 133 are electrically connected. Note that as long as the lighting cables 130 can be electrically connected to each other, various conventionally used connecting jig CN structures, such as clip-type connectors, can be used, not limited to the structure shown in Figure 2(b).

[0030] The mechanism by which the detection light 120 outputs visible light when the pull rope switch 110 is activated will be explained below. The pull rope switch 110 is powered by electricity supplied from a power supply device installed outside the mine, for example, meaning that electricity flows through the pull rope switch 110 (current is generated). The pull rope switch 110 also has a contact changeover switch 111 and two or more cable contacts 112, and the cable from the power supply device is connected to these cable contacts 112. For example, in Figure 4, the pull rope switch 110 has three cable contacts 112 (first cable contact 112a, second cable contact 112b, and third cable contact 112c), and two cables (pull rope cable EC1 and pull rope cable EC2) are connected to the power supply device, and one pull rope cable EC1 is connected to the first cable contact 112a, while the other pull rope cable EC2 is connected to the third cable contact 112c.

[0031] Figure 4 is a schematic model diagram illustrating the relationship between the pull rope switch 110 and the current, where (a) shows the situation when electricity is flowing through the pull rope switch 110, and (b) shows the situation when electricity is not flowing through the pull rope switch 110. Furthermore, Figure 4(a) represents the normal state where the pull rope switch 110 is not activated (the belt conveyor 200 is not stopped), and Figure 4(b) represents the state where the pull rope switch 110 is activated (the belt conveyor 200 is stopped). In Figure 4(a), since the contact changeover switch 111 connects the first cable contact 112a and the third cable contact 112c, the electrical circuit consisting of the power supply unit ~ pull rope switch 110 ~ power supply unit is closed, meaning that electricity flows through the pull rope switch 110.

[0032] When the pull rope of the pull rope switch 110 is pulled, the belt conveyor 200 is stopped and the contact changeover switch 111 is switched. Specifically, as shown in Figure 4(b), the contact changeover switch 111 switches from a state where the first cable contact 112a and the third cable contact 112c are connected to a state where the second cable contact 112b and the third cable contact 112c are connected. As a result, the electrical circuit consisting of the power supply unit, the pull rope switch 110, and the power supply unit is opened, meaning that no electricity flows to the pull rope switch 110.

[0033] Meanwhile, two lighting cables 130 (a first lighting cable 130a and a second lighting cable 130b) are connected to the detection light 120, and each is connected to a cable contact 112. For example, in Figure 4, one of the first lighting cables 130a is connected to the second cable contact 112b, and the other second lighting cable 130b is connected to the third cable contact 112c.

[0034] As shown in Figure 4(a), when the pull-cord switch 110 is not activated, the contact changeover switch 111 connects the first cable contact 112a and the third cable contact 112c. As a result, the electrical circuit consisting of the detection light 120, the second cable contact 112b, the third cable contact 112c, and the detection light 120 is open, meaning that no electricity flows to the pull-cord switch 110. Naturally, the detection light 120 does not emit visible light at this time.

[0035] In contrast, as shown in Figure 4(b), when the pull rope switch 110 is activated, the contact changeover switch 111 connects the second cable contact 112b and the third cable contact 112c. As a result, the electrical circuit consisting of the detection light 120, the second cable contact 112b, the third cable contact 112c, and the detection light 120 is closed, meaning that electricity flows to the pull rope switch 110. Since the detection light 120 is powered by a dry cell battery or similar, the detection light 120 lights up, i.e., emits visible light.

[0036] In Figure 4, electricity flows to the pull-cord switch 110 when it is not activated, and does not flow to the pull-cord switch 110 when it is activated. However, the configuration is not limited to this; it is also possible to configure it so that electricity flows to the pull-cord switch 110 when it is activated, and does not flow to the pull-cord switch 110 when it is not activated. In any case, the detection light 120 is configured to output visible light when the pull-cord switch 110 is activated.

[0037] The detection light 120 can be made portable, meaning it can be used like a flashlight. In this case, the lighting cable 130 is configured to be detachably connected to the detection light 120, as shown in Figure 2(b). The detection light 120 is configured so that an internal electrical circuit is opened and closed by a control switch. Therefore, the worker can carry the detection light 120 after disconnecting it from the lighting cable 130, and can also turn on the detection light 120 (output visible light) by operating the control switch (i.e., operating the power supply).

[0038] 2. Anomaly detection system Next, the abnormal location detection system of the present invention will be explained with reference to the figures. The abnormal location detection system of the present invention is the belt conveyor stopping device 100 described so far, arranged along the belt conveyor 200. Therefore, explanations that overlap with those described for the belt conveyor stopping device 100 will be avoided, and only the contents specific to the abnormal location detection system of the present invention will be explained. In other words, contents not described here are the same as those described in "1. Belt Conveyor Stopping Device".

[0039] As shown in Figure 5, the abnormal location detection system 300 of the present invention comprises a belt conveyor 200 and a belt conveyor stopping device 100 positioned to the side of the belt conveyor 200. More specifically, multiple belt conveyor stopping devices 100 are installed along the belt conveyor 200, with predetermined intervals in the axial direction of the belt conveyor 200.

[0040] As explained above, when the pull rope switch 110 is activated and stops the belt conveyor 200, the detection light 120 emits visible light. Therefore, even in underground environments where dust and other particles tend to accumulate, or in cases where the belt conveyor 200 is placed at a relatively high position to make effective use of underground space, the detection light 120 that emits visible light can be easily found, and thus the location of any abnormalities in the belt conveyor 200 can be easily identified. For example, in Figure 5, the third detection light 120 from the left is lit, and it can be determined that the pull rope switch 110 associated with that detection light 120 has stopped the belt conveyor 200. In this way, with the abnormality detection system 300, even if a large number of pull rope switches 110 are installed, the activated pull rope switch 110 can be quickly identified without wasting time, and as a result, the location of any abnormalities in the belt conveyor 200 can be easily identified. Furthermore, by making the detection light 120 portable, flashlights can be placed in the mine at predetermined intervals, and the detection light 120 can be effectively utilized even when the lighting in the mine is interrupted, which is preferable. [Industrial applicability]

[0041] The belt conveyor stopping device and abnormal location detection system of the present invention can be used in tunnel excavation for various purposes, such as railway tunnels and road tunnels, as well as in any situation where rock is excavated and transported, such as in quarries. Considering that it can construct social infrastructure such as tunnel structures more safely, the present invention is not only industrially applicable but also has the potential to make a significant contribution to society. [Explanation of Symbols]

[0042] 100 Belt conveyor stopping device of the present invention 110 Pull rope switch 112 Cable contacts 111 Contact Selector Switch 112a First cable contact 112b Second cable contact 112c Third cable contact 120 detection lights 130 Lighting Cable 130a Cable for the first light 130b Cable for second lighting 131 Downward Cable 132 Upward Cable 133 Intermediate Cable 200 Belt Conveyor CN connection jig CNa concave side jig CNb convex side jig LC lining concrete MB Belt Conveyor Stand Mounting bracket for MF detection light MS pull-cord switch mounting base

Claims

1. A device for stopping a belt conveyor operating in a tunnel under excavation, A pull-cord switch, which is installed on a frame for a belt conveyor and has a pull cord, The system includes a detection lamp connected to the aforementioned pull-cord switch and emitting visible light, The aforementioned pull rope switch stops the belt conveyor when the pull rope is pulled. The detection light emits visible light when the pull rope switch stops the belt conveyor. The aforementioned detection light is installed on a mounting base for detection lights attached to the lining concrete and positioned below the mounting base for the belt conveyor. A belt conveyor stopping device characterized by the following features.

2. The aforementioned pull rope switch has a contact changeover switch and two or more cable contacts, The two lighting cables connected to the aforementioned detection lamp are each connected to different cable contacts. When the pull rope is pulled, the contact change switch connects the cable contacts to which the lighting cable is connected, causing the detection lamp to emit visible light. The belt conveyor stopping device according to claim 1, characterized in that it is a belt conveyor stopping device.

3. The aforementioned detection light is positioned within reach of a person, is detachably attached to two of the aforementioned lighting cables, and is portable. The detection lamp, which has been removed from the aforementioned lighting cable, outputs visible light when the power is operated. The belt conveyor stopping device according to feature 2.

4. A system for detecting an abnormal location on a belt conveyor using the belt conveyor stopping device described in any one of claims 1 to 3, The aforementioned belt conveyor and, The system includes belt conveyor stopping devices installed at multiple locations along the belt conveyor at intervals, When the pull rope switch that stops the belt conveyor stops the belt conveyor, the detection light emits visible light, thereby enabling the detection of abnormal areas in the belt conveyor. An abnormal location detection system characterized by the following features.

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