Safety device

Abstract

To provide a safety device capable of effectively preventing an object from coming into contact with a rotating body which advances a working machine in an advancing direction by rotating.SOLUTION: A safety device attached to a work machine having a rotating body that causes the work machine to travel in a traveling direction by rotating, the safety device comprising a sensor that detects an object in front of the rotating body in the traveling direction, wherein the sensor outputs a signal for causing the work machine to perform a predetermined operation when the object is detected. At least a part of the sensor may be attached to a position overlapping the rotating body as viewed in the traveling direction.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present disclosure relates to safety devices. [Background technology]

[0002] Patent Document 1 discloses a contact sensor that detects when a person enters a work area around a construction vehicle, and a method for using the contact sensor. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent No. 3126710 Summary of the Invention [Problem to be solved by the invention]

[0004] However, the technology disclosed in Patent Document 1 may not be able to effectively prevent objects from coming into contact with rotating bodies that rotate to propel the work machine, such as the crawlers of a crawler-type work machine.

[0005] Therefore, in one aspect, the present invention aims to provide a safety device that can effectively prevent objects from coming into contact with a rotating body that rotates to move a work machine in a traveling direction. [Means for solving the problem]

[0006] In one embodiment, A safety device that is attached to a work machine having a rotating body that rotates to cause the work machine to travel in a forward direction, a sensor for detecting an object in front of the rotating body in the traveling direction; A safety device is provided in which the sensor outputs a signal to cause a predetermined action to be taken on the work machine when the object is detected. [Effects of the Invention]

[0007] According to one aspect, the present invention can effectively prevent objects from coming into contact with a rotating body that rotates to move a work machine in a traveling direction. [Brief explanation of the drawings]

[0008] [Figure 1] FIG. 2 is a side view showing the configuration of the safety device of the present embodiment. [Figure 1A] FIG. 2 is a top view showing the configuration of the safety device of the present embodiment. [Figure 2] FIG. 1 is a diagram illustrating an example of a work machine. [Figure 2A] FIG. 1 is a diagram illustrating an example of a work machine. [Figure 3] FIG. 10 is a diagram illustrating the function of a safety device. [Figure 4] FIG. 10 is a side view showing the configuration of a safety device provided with a plurality of sensors. [Figure 4A] 5 is a front view (viewed from the right side of FIG. 4) showing the configuration of a safety device provided with a plurality of sensors. DETAILED DESCRIPTION OF THE INVENTION

[0009] FIG. 1 is a side view showing the configuration of the safety device of this embodiment, FIG. 1A is a top view showing the configuration of the safety device of this embodiment, FIGS. 2 and 2A are diagrams showing an example of a work machine, and FIG. 3 is a diagram showing the function of the safety device.

[0010] As shown in FIGS. 1 and 1A, the safety device of this embodiment includes a tape-shaped sensor 20 (tape switch) and a support member 30 that supports the sensor 20.

[0011] As shown in Figure 3, the sensor 20 has a switch 22 whose state changes depending on whether or not pressure is applied. For example, if the switch 22 is in the on state under normal circumstances when no pressure is applied to the sensor 20, when an object comes into contact with the sensor 20 and the sensor 20 is deformed in a direction that causes it to be crushed (a direction that reduces its thickness) due to the pressure, the switch 22 changes state to the off state. When using this type of sensor 20, the switch 22 can be inserted in series, for example, in a limit switch for a safety lever that ensures safety when getting on a backhoe, or in the line of a fuse connected to the engine. In this case, special control devices and control panels are not required, which allows for cost reduction.

[0012] Furthermore, when switch 22 is in the off state under normal circumstances when no pressure is applied to sensor 20, if an object comes into contact with sensor 20 and the pressure causes sensor 20 to deform in a direction that crushes it, switch 22 will turn on.

[0013] As shown in FIGS. 1 and 1A, the support member 30 has an attachment portion 31 to which the sensor 20 is attached, and a support portion 32 connected to the attachment portion 31. Furthermore, magnet plates 4A, 4B, and 4C, each using a neodymium magnet, are attached to the support member 30 (support portion 32). To enhance the versatility of the safety device, the shape and size of the support member 30 may be made variable. For example, the length (the length in the left-right direction in FIG. 1) of the support portion 32 of the support member 30 may be variable.

[0014] 2 and 2A, the work machine 50 may be a relatively small heavy machine such as a mini backhoe or a small aerial work vehicle. The work machine 50 is provided with a crawler 52 as a rotating body, and travels in a predetermined direction corresponding to the rotation direction of the crawler 52 as the crawler 52 rotates.

[0015] In the example shown in Figures 2 and 2A, work machine 50 has part 51 (Figure 2A) made of a magnetic material to which support member 30 can be attached. Part 51 is located near crawler 52 and functions as a frame that rotatably supports crawler 52. Therefore, part 51 does not rotate even when crawler 52 rotates. As shown in Figure 2, support member 30 is detachable from part 51 via magnet board 4A, magnet board 4B, and magnet board 4C. This makes it possible to apply the safety device to a variety of work machines at low cost. It also reduces the cost of restoring the safety device to a detached state.

[0016] When the support member 30 is attached to the portion 51 via the magnet boards 4A, 4B, and 4C, the attachment portion 31 and the sensor 20 are arranged to extend in a direction substantially parallel to the drive shaft (not shown) of the crawler 52 in the vicinity of the crawler 52. The state of the switch 22 is output as a signal via the cable 21 (FIGS. 2 and 3). Incidentally, by inserting a slip ring in the path of the cable 21, twisting of the cable 21 can be prevented. Furthermore, instead of using the cable 21, the state of the switch 22 may be output via wireless communication.

[0017] Next, the operation of the safety device of this embodiment will be described. By attaching the support member 30 to the portion 51 via the magnet boards 4A, 4B, and 4C, the sensor 20 can detect an object.

[0018] When the crawler 52 is driven and the work machine 50 moves in one direction (to the right in Figures 1 and 1A), the sensor 20 attached to the mounting portion 31 is positioned ahead of the crawler 52 in the direction of travel of the work machine 50.

[0019] When an object (including a person) comes into contact with the sensor 20, the sensor 20 deforms, causing the state of the switch 22 to change, and a predetermined detection signal is output via the cable 21. This detection signal functions, for example, as a limit switch or as a signal corresponding to the disconnection state of a fuse line connected to the engine, as described above, or is input to a control device (not shown) of the work machine 50. When the limit switch or the fuse line connected to the engine is disconnected, the rotation of the crawler 52 can be directly stopped. When the detection signal is input to the control device, the rotation of the crawler 52 can be stopped by control from the control device. This causes the traveling work machine 50 to stop. Furthermore, when this detection signal is output, along with the stopping of traveling, an alarm may be issued, for example, to notify the worker that an object has been detected by the sensor 20.

[0020] In this embodiment, the sensor 20 is provided ahead of the crawler 52 in the direction of travel of the work machine 50. Therefore, the sensor 20 can detect an object before the object comes into contact with the crawler 52. Therefore, the object can be effectively prevented from coming into contact with the crawler 52.

[0021] As in this embodiment, it is desirable that at least a portion of the sensor 20 be attached in a position that overlaps with the crawler 52 when viewed in the direction of travel of the work machine 50. If this condition is met, it is possible to detect objects in a position in front of the crawler 52 in the direction of travel of the work machine 50. Therefore, it is possible to effectively detect objects that may come into contact with the crawler 52. However, by providing the sensor 20 beyond the area that overlaps with the crawler 52 in the direction of travel of the work machine 50, it is possible to detect objects over a wider range. Therefore, it is possible to effectively prevent, for example, moving objects (such as people) from coming into contact with the crawler 52.

[0022] Although a single sensor 20 is used in the above embodiment, a plurality of sensors 20 may be provided in the safety device.

[0023] FIG. 4 is a side view showing the configuration of a safety device provided with a plurality of sensors, and FIG. 4A is a front view (viewed from the right side of FIG. 4) showing the configuration of a safety device provided with a plurality of sensors.

[0024] The safety device shown in FIGS. 4 and 4A includes a pair of sensors 20 and a support member 30A that supports the pair of sensors 20.

[0025] The support member 30 has a pair of attachment portions 31A to which the sensors 20 are respectively attached. Furthermore, magnet plates 4D, 4E, 4F and 4G using neodymium magnets are attached to the support member 30A.

[0026] When the support member 30A is attached to the portion 51 via the magnet boards 4D, 4E, 4F and 4G, the pair of attachment portions 31A are arranged at different heights near the crawler 52 so as to extend in a direction approximately parallel to the drive shaft (not shown) of the crawler 52.

[0027] 4 and 4A, a pair of sensors 20 are provided at positions at different heights. This allows the detection range of an article to be expanded from a low position to a high position, and objects in front of the crawler 52 can be detected with higher accuracy. This further improves the functionality of the safety device.

[0028] In this embodiment, it is preferable to configure a circuit including the switch 22 so that a detection signal is output when either of the pair of sensors 20 detects an object. For example, if the switch 22 is in an on state when no pressure is applied to the sensor 20 and is turned off when an object comes into contact with the sensor 20, the pair of switches 22 can be connected in series. Alternatively, if the switch 22 is in an off state when no pressure is applied to the sensor 20 and is turned on when an object comes into contact with the sensor 20, the pair of switches 22 can be connected in parallel. This makes it possible to output the logical sum of the detection results (detection results indicating contact of an object) of the pair of sensors 20 as a detection signal.

[0029] There is no limitation on the number of sensors 20. For example, in particular when the height (diameter) of a rotating body such as the crawler 52 is large, the number of sensors 20 may be three or more in order to expand the object detection range. Also, multiple sensors 20 may be arranged in the horizontal direction.

[0030] As described above, according to this embodiment, the sensor 20 is provided to detect an object ahead of the rotating crawler 52 in the direction of travel, and when an object is detected, the sensor 20 outputs a signal to cause the work machine 50 to perform a predetermined operation. This makes it possible to effectively prevent objects from coming into contact with the rotating body that rotates to move the work machine 50 in the direction of travel.

[0031] For example, in narrow work sites where a mini-backhoe is used, there are cases where people and heavy machinery work together. In such work sites, there is a risk of contact with nearby workers when the mini-backhoe is reversing. The safety devices of the above embodiments make it possible to stop a work machine 50 such as a mini-backhoe with a simple configuration. This makes it possible to prevent contact between the work machine 50 and workers at a relatively low cost. Note that by additionally attaching a similar sensor 20 so that it protrudes at the same height as the counterweight of the mini-backhoe, contact with parts other than the crawler 52 can also be prevented.

[0032] Although the embodiments have been described in detail above, they are not limited to the specific embodiments, and various modifications and changes are possible within the scope of the claims. For example, in the embodiments, crawlers 52 are used as examples of rotating bodies, but the rotating body is not limited to this and may include, for example, tires, rollers, etc. Furthermore, in the embodiments, a so-called tape switch is used as the sensor 20, but a so-called whisker limit switch or the like may also be used. [Explanation of symbols]

[0033] 20 sensors 22 Switch 30 Support member 30A Support member 50 Work Machinery 51 parts 52 Crawler

Claims

1. A safety device that is attached to a work machine having a rotating body that rotates to cause the work machine to travel in a forward direction, a sensor for detecting an object in front of the rotating body in the traveling direction; A safety device in which the sensor outputs a signal to cause the work machine to perform a predetermined operation when the object is detected.

2. The safety device according to claim 1 , wherein at least a portion of the sensor is attached at a position overlapping the rotating body when viewed in the traveling direction.

3. The safety device according to claim 1 , wherein the signal causes the rotating body to stop rotating as the predetermined action.

4. 2. The safety device of claim 1, wherein the sensor comprises a switch that outputs the signal when contacted by the object.

5. a support member for supporting the sensor; 2. The safety device according to claim 1, wherein the support member is detachably attached to a portion of the work machine other than the rotating body.

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