Safety equipment and garbage collection vehicles

Abstract

To provide a safety device capable of enhancing safety without reducing working efficiency, and a refuse collecting vehicle having the safety device.SOLUTION: A safety device used in a refuse collecting vehicle 1 having a loading device includes: an electrode part 10 which is separated from a vehicle body of the refuse collecting vehicle 1 and is installed on an approach side of a person 6; an electrostatic capacitance sensor 20 which applies a signal to the electrode part 10, and measures electrostatic capacitance between the electrode part 10 and the vehicle body changed by a degree of approach of the person 6 to the electrode 10, and a degree of further approach of a partial body of the person 6 approaching the electrode part 10 to the vehicle body or the loading device from the position; and control means 30 which uses a change in the electrostatic capacitance measured by the electrostatic capacitance sensor 20, in control.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a safety device that detects the approach of a person to a machine in operation in order to prevent an accident such as the person being caught in the machine, and to a garbage collection vehicle equipped with the safety device. [Background technology]

[0002] FIG. 10 is a schematic diagram of a conventional rotary garbage collection vehicle, where FIG. 10(a) is a side view and FIG. 10(b) is a perspective view of a drop box. The refuse collection vehicle 1 is equipped with a dump box 2 having an inlet 2a at the rear through which refuse (garbage) is dumped, and a storage box 3 for storing the dumped garbage. Inside the dump box 2, a loading device having movable parts such as a push plate 2b and a rotating plate 2c is provided. While a worker is manually loading garbage into the trash box 2, the rotating plate 2c rotates near the loading port 2a. This raises the risk of an accident in which the worker gets caught in the rotating plate 2c. This risk is particularly high when the loading device is operating continuously. This concern is the same for press-type refuse collection vehicles, and even for vehicles or devices other than refuse collection vehicles, if they have moving parts such as rotating mechanisms or cutting mechanisms, there is a possibility of serious accidents occurring, such as being caught or pinched in the moving parts. Therefore, it is necessary to prevent workers from carelessly approaching these machines while they are in operation.

[0003] Patent document 1 discloses a monitoring system for a garbage collection vehicle equipped with a loading device that sends garbage from a garbage dump box into a garbage storage box, and includes an imaging means that captures images of the garbage dump opening and the area outside it, an image processing device that recognizes the presence of a person within the imaging range based on an input image captured by the imaging means, and a control device that controls the stopping of the operation of the loading device. Patent document 2 also discloses a safety device for a garbage truck that includes a proximity switch that activates when the rotating plate of the garbage loading device reaches the beginning of a dangerous operating range within the range of motion of the rotating plate where an entrapment accident may occur, a timer that starts when the proximity switch is activated and stops after a certain period of time, an electromagnetic wave sensor that is located at the rear of the garbage truck near the garbage inlet and can detect human bodies, a voice switch that is located near the garbage inlet and activates when it detects a sound above a certain volume, and a control unit that brings the garbage loading device to an emergency stop when the electromagnetic wave sensor or voice switch is activated during the timer's operating time. Furthermore, Patent Document 3 discloses an electrode system of an electrostatic proximity sensor that is attached to the surface of an automobile bumper to detect a human body or the like approaching the bumper. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Laid-Open No. 2004-269137 [Patent Document 2] Japanese Patent Application Laid-Open No. 2015-040102 [Patent Document 3] Japanese Patent Application Laid-Open No. 2010-276524 Summary of the Invention [Problem to be solved by the invention]

[0005] The monitoring system described in Patent Document 1 requires an imaging device and an image processing device, which can lead to high costs. Furthermore, the system stops the operation of the loading device when it detects that a person is in a restricted area. However, even if a worker is close to the refuse collection vehicle, depending on their posture, the risk may not be high enough to stop the operation of the loading device. If the loading device is stopped until the risk is not so high, workers may turn off the monitoring system to avoid a decrease in work efficiency. Furthermore, the safety device described in Patent Document 2 requires multiple sensors and timers, which makes the configuration complex and expensive. Furthermore, when the rotating plate is in a dangerous range where it could be caught in something and cause an accident, an electromagnetic wave sensor installed below the bumper or elsewhere detects a human body and brings the rotating plate to an emergency stop. Therefore, similar to Patent Document 1, the rotating plate is stopped even when the risk is not that high. Therefore, in the case of Patent Document 2, there is also a possibility that workers will turn off the monitoring system to avoid a decrease in work efficiency. Furthermore, the electrode system of Patent Document 3 does not relate to a safety device used in a machine having a moving part. SUMMARY OF THE INVENTION It is therefore an object of the present invention to provide a safety device that can improve safety without reducing work efficiency, and a garbage collection vehicle equipped with the safety device. [Means for solving the problem]

[0006] The safety device of the present invention as set forth in claim 1 comprises: moving part Equipped with machine A safety device for use in Machinery and moving parts The electrode unit 10 is installed on the side of the person 6 approaching the electrode unit 10 at a distance from the electrode unit 10, and a signal is applied to the electrode unit 10 to measure the degree of approach of the person 6 to the electrode unit 10 and the degree to which the person 6 approaches the electrode unit 10 and moves part of their body from that position. machine or moving part The electrode part 10 changes depending on the degree to which it is brought closer to the machine a capacitance sensor 20 for measuring the capacitance between the electrodes; and a control means 30 for using the change in capacitance measured by the capacitance sensor 20 for control. a support 50 having one end fixed to the machine and the other end to which the electrode unit 10 is attached; Equipped with The support 50 has an insulating member 53 that insulates the machine from the electrode unit 10. It is characterized by:

[0007] The present invention as set forth in claim 2 is the safety device as set forth in claim 1, wherein the control means 30 controls the capacitance in proportion to the change in capacitance. moving part The present invention is characterized in that the operating speed is changed in stages.

[0008] The present invention as set forth in claim 3 is the safety device as set forth in claim 2, wherein the control means 30 is configured to: moving partThe feature is that the above is stopped.

[0009] The present invention as set forth in claim 4 is the safety device as set forth in claim 3, wherein the control means 30, when the state in which the capacitance exceeds a predetermined value continues for a predetermined time, moving part is moved in the direction opposite to the direction of movement before the stop.

[0010] The present invention as set forth in claim 5 is characterized in that, in the safety device as set forth in any one of claims 1 to 4, it further comprises an alarm means 40, and the control means 30 issues a gradual alarm to the person 6 by the alarm means 40 in proportion to the change in capacitance.

[0011] The present invention as set forth in claim 6 is a safety device as set forth in any one of claims 1 to 5, wherein the electrode unit 10 comprises an insulator 13, a transmitting electrode 11 in contact with one surface of the insulator 13 and to which a signal is applied, and a transmitting electrode 11 in contact with the other surface of the insulator 13. machine and a shield electrode 12 for suppressing the parasitic capacitance generated between the machine The present invention is characterized in that the sensor is disposed in a state facing the sensor.

[0012] The present invention as set forth in claim 7 is characterized in that in the safety device as set forth in claim 6, the upper and lower ends of the insulator 13 protrude beyond the upper and lower ends of the transmitting electrode 11 and the upper and lower ends of the shield electrode 12. 。

[0013] request request 8 The garbage collection vehicle 1 of the present invention described above comprises the following: 7 1. A safety device according to claim 1, further comprising:

[0014] Claim 9 The invention as described is defined in claims 8 The garbage collection vehicle 1 described above is characterized in that an electrode unit 10 is disposed near an inlet 2a through which garbage is thrown.

[0015] Claim 10The invention as described is defined in claims 9 The garbage collection vehicle (1) described above is characterized in that the electrode part (10) has a function as an emergency stop plate (4b) that brings the operation of the movable part of the garbage collection vehicle (1) to an emergency stop by displacement.

[0016] Claim 11 The invention as described is defined in claims 8 or claims 9 The garbage collection vehicle 1 described above is characterized in that the electrode section 10 functions as a reflector 7 that reflects light from behind the vehicle. [Brief explanation of the drawings]

[0017] [Figure 1] 1 is a diagram showing the rear of a garbage collection vehicle equipped with a safety device according to an embodiment of the present invention; [Figure 2] A conceptual diagram of the change in capacitance due to the electrodes and the human body when the rotary garbage collection vehicle is viewed from the side. [Figure 3] Schematic diagram of the electrode part as viewed from the side [Figure 4] A diagram showing the surroundings of the support [Figure 5] Simplified circuit diagram of the same capacitance sensor [Figure 6] An explanatory diagram of the signal voltage (signal output value) for each state of the same worker [Figure 7] An explanatory diagram of the signal voltage (signal output value) for each state of the same worker [Figure 8] Schematic diagram of an electrode part according to another example, seen from the side [Figure 9] FIG. 10 is a diagram showing another example of an electrode installation method. [Figure 10] Schematic diagram of a conventional rotary garbage collection vehicle DETAILED DESCRIPTION OF THE INVENTION

[0018] A safety device according to a first embodiment of the present invention is a safety device used in a machine having a moving part, and comprises an electrode unit that is installed away from the machine on the side where a person approaches, a capacitance sensor that applies a signal to the electrode unit and measures the capacitance between the electrode unit and the machine, which changes depending on the degree of approach of the person to the electrode unit and the degree of further approach of the person who has approached the electrode unit to the machine or the moving part, and control means that uses the change in capacitance measured by the capacitance sensor for control. According to this embodiment, safety can be improved without reducing the work efficiency of the machine. In addition, since the system can be configured without using a camera or image processing device, it is possible to suppress the increase in costs that would otherwise be incurred by providing a safety device.

[0019] A second embodiment of the present invention is the safety device according to the first embodiment, wherein the control means changes the operating speed of the movable part in stages in proportion to a change in the capacitance. According to this embodiment, frequent emergency stops of the moving parts are suppressed, so that work efficiency can be maintained and safety can be improved.

[0020] A third embodiment of the present invention is a safety device according to the second embodiment, wherein the control means stops the moving part when the capacitance exceeds a predetermined value. According to this embodiment, safety can be further improved.

[0021] In a fourth embodiment of the present invention, in the safety device according to the third embodiment, the control means moves the movable part in the direction opposite to the direction of movement before stopping when the state in which the electrostatic capacitance exceeds a predetermined value continues for a predetermined time. According to this embodiment, the movable part is automatically reversed a certain amount, thereby making it possible to release a person from being caught (entrapped).

[0022] A fifth embodiment of the present invention is a safety device according to any one of the first to fourth embodiments, further comprising an alarm means, and the control means causes the alarm means to issue a gradual alarm to a person in proportion to a change in capacitance. According to this embodiment, people can perform work while intuitively and immediately grasping the level of danger based on the volume of the alarm sound and the illumination, color, or flashing speed of the warning light, making it easier to maintain work efficiency while improving safety.

[0023] A sixth embodiment of the present invention is a safety device according to any one of the first to fifth embodiments, wherein the electrode portion comprises an insulator, a transmitting electrode in contact with one surface of the insulator and to which a signal is applied, and a shield electrode in contact with the other surface of the insulator and which suppresses parasitic capacitance occurring between the transmitting electrode and the machine, and the shield electrode is arranged facing the machine. According to this embodiment, the degree of approach of a person can be detected with high accuracy.

[0024] A seventh embodiment of the present invention is a safety device according to the sixth embodiment, in which the upper and lower ends of the insulator protrude beyond the upper and lower ends of the transmitting electrode and the upper and lower ends of the shield electrode. According to this embodiment, it is possible to effectively prevent the transmission electrode and the shield electrode from being electrically connected via an object containing a lot of water or moisture at low cost.

[0025] An eighth embodiment of the present invention is a safety device according to any one of the first to seventh embodiments, which is provided with a support tool having one end fixed to a machine and the other end to which an electrode part is attached, and the support tool has an insulating member that insulates the machine from the electrode part. According to this embodiment, the support has a simple structure, yet has sufficient strength, and can prevent the electrode portion from being electrically connected to the vehicle body.

[0026] A refuse collection vehicle according to a ninth embodiment of the present invention is equipped with a safety device according to any one of the first to eighth embodiments. According to this embodiment, safety can be improved without reducing the operational efficiency of the refuse collection vehicle. In addition, since the system can be configured without using a camera or image processing device, it is possible to suppress the increase in costs that would otherwise be incurred by providing a safety device.

[0027] A tenth embodiment of the present invention is a garbage collection vehicle according to the ninth embodiment, in which an electrode unit is disposed near the inlet through which garbage is thrown. According to this embodiment, the electrode unit does not get in the way of work when trash is being thrown in, and the electrode unit can be prevented from coming into contact with trash, etc. Furthermore, even if there is a difference in height between the surface that the tires of the trash collection vehicle are in contact with and the surface that the soles of the workers' feet are in contact with, it is possible to accurately detect the degree of approach of the worker.

[0028] An eleventh embodiment of the present invention is a garbage collection vehicle according to the tenth embodiment, in which the electrode portion functions as an emergency stop plate that, by displacement, brings the operation of the moving parts of the garbage collection vehicle to an emergency stop. According to this embodiment, it is possible to suppress an increase in the number of components and costs due to the provision of the electrode portion.

[0029] A twelfth embodiment of the present invention is a refuse collection vehicle according to the ninth or tenth embodiment, in which the electrode portion functions as a reflector that reflects light from behind the vehicle. According to this embodiment, it is possible to suppress an increase in the number of components and costs due to the provision of the electrode portion. [Example]

[0030] Hereinafter, a safety device and a garbage collection vehicle according to an embodiment of the present invention will be described. FIG. 1 is a view showing the rear of a garbage collection vehicle equipped with a safety device according to this embodiment. The rear door of the refuse collection vehicle 1 is pulled up to open the drop-in opening 2a. Although not shown in the figure, a loading device is provided inside the drop-in box 2. The vehicle body and the loading device are made mainly of metal such as steel and are electrically conductive. The refuse collection vehicle 1 is equipped with emergency stop switches 4 for emergency stopping the loading device, including emergency stop buttons 4a on the left and right sides of the inlet 2a and a rectangular emergency stop plate 4b below the inlet 2a. An operator can forcibly stop the operation of the loading device by pressing the emergency stop button 4a with his / her hand or by pushing and displacing the emergency stop plate 4b with his / her knee or the like. A table 5 that can rotate around a horizontal axis is provided at the bottom of the drop-in port 2a. The table 5 is in an unused state, standing approximately vertically, while the vehicle is moving, and is in an unused state, unfolded approximately horizontally as shown in Figure 1, when the vehicle is stopped at a garbage dump or the like and garbage is manually loaded.

[0031] The garbage collection vehicle 1 is equipped with a safety device. The safety device comprises an electrode unit 10 that is installed away from the garbage collection vehicle 1 on the side where a person (worker) approaches, a capacitance sensor 20 that applies a signal to the electrode unit 10 and measures the capacitance between the electrode unit 10 and the body of the garbage collection vehicle 1, control means 30 that uses the change in capacitance measured by the capacitance sensor 20 for control, and alarm means 40 that is installed near the drop box 2 and issues an alarm to the worker by sound or light. The electrode unit 10 is disposed near the input opening 2a. In this embodiment, the electrode unit 10 is disposed below the input opening 2a, and when the table 5 is in the usable state, the upper surface of the electrode unit 10 is covered by the table 5. By disposing the electrode unit 10 below the input opening 2a, the electrode unit 10 does not get in the way of the operation when inserting waste, and the electrode unit 10 can be prevented from coming into contact with the waste and being damaged.

[0032] Figure 2 is a conceptual diagram of the change in capacitance due to the electrode part and the human body when the rotary garbage collection vehicle is viewed from the side. Figure 2(a) shows the state when no human body is approaching, and Figure 2(b) shows the state when a human body is approaching. The electrode unit 10 is installed below the input port 2a. Between the electrode unit 10 and the body of the refuse collection vehicle 1, a circuit of a capacitance sensor 20 is provided. When no person (worker) 6 is approaching the rear of the refuse collection vehicle 1, a small parasitic capacitance occurs between the electrode unit 10 and the vehicle body, as shown in FIG. 2(a). When a worker 6 approaches the rear of the garbage collection truck 1 and the distance between the electrode unit 10 falls below a certain level, the capacitance between the electrode unit 10 and the vehicle body via the human body increases, as shown in Figure 2(b). This capacitance increases in proportion to the area and distance that the worker 6 faces the electrode, and further increases when the distance between the human body and the vehicle body or the rotating plate 2c decreases, such as when the worker 6 places his or her hand on the table 5 or inserts his or her hand into the inlet 2a to push garbage in. The capacitance sensor 20 measures the capacitance that changes depending on the degree of approach of the worker 6 to the electrode unit 10 and the degree of further approach of the worker 6 who has approached the electrode unit 10 to the body or loading device of the garbage collection truck 1.

[0033] FIG. 3 is a schematic diagram of the electrode portion as viewed from the side. The electrode unit 10 includes a metallic transmitting electrode 11 to which a signal from the capacitance sensor 20 is applied, a metallic shield electrode 12 that suppresses parasitic capacitance that occurs between the transmitting electrode 11 and the vehicle body, and an insulator 13 that shields and insulates the transmitting electrode 11 from the shield electrode 12. The transmitting electrode 11 is insulated from the shield electrode 12, and the shield electrode 12 is insulated from the vehicle body, with the shield electrode 12 installed facing the vehicle body. The transmitting electrode 11 faces the side from which the worker 6 is approaching. This allows the degree of approach of the worker 6 to be detected with high accuracy. The transmitting electrode 11, the shield electrode 12, and the insulator 13 are, for example, rectangular plate-shaped, but may also be U-shaped. Alternatively, the transmitting electrode 11 and the shield electrode 12 may be plate-shaped, with only the insulator 13 being U-shaped. The transmitting electrode 11 contacts one side of the insulator 13, and the shield electrode 12 contacts the other side of the insulator 13. By forming the insulator 13 to a predetermined thickness, the distance between the transmitting electrode 11 and the shield electrode 12 is maintained at a certain level or more so that the electrostatic capacitance between the transmitting electrode 11 and the shield electrode 12 does not become too large. The thickness of the insulator 13 is set to be equal to or greater than the thickness of the transmitting electrode 11 and the shield electrode 12, for example, 10 to 20 mm. The safety device includes a support 50, and the electrode unit 10 is connected to the rear surface of the vehicle body via the support 50. By forming the support 50 to a predetermined length, the distance between the shield electrode 12 and the vehicle body is maintained at a certain level so that the electrostatic capacitance between the shield electrode 12 and the vehicle body does not become too large. In addition, the support 50, which is present between the transmitting electrode 11, the shield electrode 12, and the vehicle body, has a relative dielectric constant of a certain level or less. The electrode section 10 configured in this manner is sturdy and will not be easily damaged even if the leg or the like of the worker 6 hits it.

[0034] FIG. 4 shows the periphery of the support tool, with FIG. 4(a) being a perspective view and FIG. 4(b) being a top view. One end of the support 50 is fixed to the vehicle body, and the electrode unit 10 is attached to the other end. The support 50 is preferably made of metal from the standpoint of strength, durability, etc., but insulation between the vehicle body and the electrode unit 10 is necessary. Therefore, the support 50 of this embodiment connects a first metal member 51 connected to the vehicle body and a second metal member 52 connected to the electrode unit 10 via two rubber insulating members 53. This makes it possible to prevent electrical connection between the electrode unit 10 and the vehicle body while ensuring sufficient strength of the support 50 despite its simple structure.

[0035] FIG. 5 is a simplified circuit diagram of a capacitance sensor. An example of a signal processing procedure on the circuit of the capacitance sensor 20 is shown below. (1) Outputs a square wave signal according to the oscillation frequency of the crystal oscillator. (2) Convert the output square wave signal to 500 kHz (divide by 500 kHz). (3) The converted transmission signal, which is a rectangular wave of 500 kHz, is output to the transmission electrode 11. (4) In the circuit indicated by the dotted line A, the signal is divided according to a voltage division ratio that changes according to the capacitance. When the worker 6 approaches the transmitting electrode 11, the impedance decreases via the human body. (5) A sine wave of a specific frequency (500 kHz) is extracted through the voltage follower circuit (dotted line B) and the bandpass filter circuit (dotted line C). (6) The detection circuit indicated by the dotted line D extracts the amplitude of the sine wave as a DC signal voltage. (7) The obtained signal voltage is output to the control means 30. Additionally, an active shield is connected downstream of the circuit indicated by dotted line A via a voltage follower circuit indicated by dotted line E as shield electrode 12. This reduces the parasitic capacitance between the vehicle body and transmitting electrode 11, making it possible to detect minute changes in capacitance. In order to prevent interference with surrounding electromagnetic noise, specific information may be added to the signal sent from the circuit. Also, in step (2) above, a frequency other than 500 kHz may be used for the square wave as appropriate. It may also be provided with a function to distinguish between wet dust or the like with a high dielectric constant and a human body. Alternatively, it is also effective to provide a function to automatically correct the detection sensitivity of the capacitance sensor 20 according to the surrounding environment. The bandpass filter and detector circuit may be replaced with other elements that have equivalent functions. Examples of bandpass filter circuit replacements include a circuit with multiple bandpass filters stacked on top of each other, or an active filter circuit using an amplifier. Examples of detector circuit replacements include a full-wave rectifier circuit, a bridge rectifier circuit, a Cockcroft-Walton circuit, or a (half-wave or full-wave) voltage doubler rectifier circuit. Instead of the bandpass filter and detector circuit, the signal can be input into a microcontroller or other device, and noise can be reduced or detected using digital signal processing.

[0036] 6 and 7 are explanatory diagrams of the signal voltage (signal output value) in each state of the worker. The sensing distance of the capacitance sensor 20 from the electrode part 10 is set to about 0 to 100 mm. Fig. 6(a) shows a state in which worker 6 is inserting garbage from a position more than 100 mm away from the insertion opening. Fig. 6(b) shows a state in which worker 6 is standing upright at a position more than 100 mm away from electrode unit 10. In either state, capacitance sensor 20 barely reacts. Furthermore, the capacitance sensor 20 does not react when dust is placed in the insertion port 2a or when dry dust comes into contact with the vicinity of the electrode portion 10, thereby reducing the possibility of false detection due to such dust. On the other hand, the capacitance sensor 20 reacts in all of the states shown in Figure 7. Figures 7(a) to (c) show the worker 6 leaning forward with his legs positioned approximately 100 mm from the electrode unit 10. The degree to which the upper body is inserted into the dropping box 2 is smallest in the state of Figure 7(a) and largest in the state of Figure 7(c). Figure 7(d) shows the worker 6 standing upright in a position where he is in close contact with the electrode unit 10. The signal output value is smallest in the state of Figure 7(a), and increases in the order of Figure 7(b), Figure 7(c), and Figure 7(d). The capacitance sensor 20 can respond according to the degree of proximity of a human body even through gloves or dry dust.

[0037] As described above, when the worker 6 approaches the electrode unit 10 or when the worker 6 enters the drop box 2 and the distance between the worker 6 and the vehicle body or the rotating plate 2c decreases, the capacitance increases and the signal output value increases. Therefore, the signal output value can be regarded as the danger level of the worker 6. The control means 30 controls the operation of the loading device and the warning issued by the warning means 40 based on the signal voltage output from the capacitance sensor 20. Because the signal output value output from the capacitance sensor 20 is continuous (analog value), the control means 30 can perform control based on the ambiguous state that the worker 6 is in, such as "safe - slightly dangerous (caution) - dangerous", rather than performing control that discretely divides the state that the worker 6 is in, such as "safe or dangerous".

[0038] The control means 30 changes the operating speed of the loading device in stages according to the voltage value from the capacitance sensor 20. For example, if the voltage value is lower than a first predetermined value, i.e., if the risk is low, the operating speed of the rotating plate 2c is normal; if the capacitance is equal to or greater than the first predetermined value and less than a second predetermined value, i.e., if the risk is medium, the operating speed is slower than normal; and if the capacitance is equal to or greater than the second predetermined value, i.e., if the risk is high, the rotating plate 2c is stopped. Methods for suppressing the speed include reducing the engine speed of the hydraulic drive source and slowing the operating speed by controlling the flow rate of the hydraulic circuit. In this way, safety can be improved by changing the operating speed of the loading device based on the distance between the worker 6 and the electrode unit 10 or the distance between the worker 6 and the vehicle body or the loading device, and stopping the device when the risk level increases. Furthermore, when the risk level is medium, the operation of the loading device slows down, reducing the efficiency of garbage collection. Therefore, the worker 6 will maintain an appropriate distance from the garbage collection vehicle 1 to avoid the loading device slowing down or stopping due to a further increase in the risk level. This prevents the loading device from making frequent emergency stops, maintaining work efficiency and improving safety. Furthermore, maintaining work efficiency also reduces the likelihood that the worker 6 will turn off the power to the safety device to avoid a decrease in work efficiency. The control means 30 also controls the alarm means 40 to issue a stepped alarm in accordance with the voltage value from the capacitance sensor 20. For example, if the alarm means 40 has a speaker, the volume of the alarm sound increases as the voltage value increases. If the alarm means 40 has a warning light, the illumination intensity or color of the warning light is changed as the voltage value increases, or the blinking rate is increased if the warning light is blinking. This allows the worker 6 to perform work while intuitively and immediately grasping the level of danger based on the volume of the alarm sound or the illumination intensity, color, or blinking rate of the warning light, making it easier to maintain work efficiency while improving safety.

[0039] If the degree of approach (risk level) exceeds a second predetermined value and continues for a predetermined time, the control means 30 moves the rotating plate 2c slightly in the opposite direction to the direction of movement before it was stopped. If the high-risk state does not disappear even after the rotating plate 2c has stopped, there is a possibility that the worker 6 is unable to move because his / her hand has become caught or pinched in the rotating plate 2c. Since it is impossible for the worker 6 in this state to perform the reversing operation himself / herself, the rotating plate 2c is automatically reversed a certain amount to free the worker 6 from the caught (pinched) state. In addition, an angle sensor or the like may be provided to detect the position of the rotating plate 2c when the loading device makes an emergency stop, and based on the results, it may be used to auxiliary determine whether the worker 6 is caught and unable to move.

[0040] As described above, the safety device of the present invention can increase safety without reducing the operational efficiency of the refuse collection vehicle 1. Furthermore, since the safety device can be configured without using a camera or image processing device, the safety device can be provided at low cost. It is also possible to install a human body detection sensor of a different type from the capacitance sensor 20 and use it to assist the judgment of the control means 30. For example, an ultrasonic or radar detection device is installed above the insertion port 2a, and ultrasonic or radar is emitted downward to detect a human body attempting to enter the insertion port 2a, which is a dangerous area. The control means 30 combines the detection results of this device with those of the capacitance sensor 20 to determine control. This can improve the accuracy of the safety device. Furthermore, although the electrode unit 10 is disposed below the input port 2a in the above-described embodiment, the electrode unit 10 can also be disposed near the input port 2a, on the side or top surface of the input port 2a. By disposing the electrode unit 10 on the side or top surface of the input port 2a, it is possible to accurately detect the degree of approach of the worker 6 even when the tires of the garbage collection truck 1 and the soles of the worker's 6 are not at the same height on the ground in places where there are differences in floor elevation to allow for loading and unloading of luggage onto trucks, such as the back yard of a hotel or store facility. Note that the electrode unit 10 can also be installed in at least two locations, below, on the side, and on the top surface of the input port 2a.

[0041] FIG. 8 is a schematic diagram of an electrode portion according to another example, as viewed from the side. If water accumulates on the upper surface of the electrode unit 10 or if water droplets adhere to the lower surface of the electrode unit 10, there is a possibility that the transmitting electrode 11 and the shield electrode 12 may be electrically connected via the water. Therefore, it is preferable to implement measures in the electrode unit 10 to prevent electrical connection between the transmitting electrode 11 and the shield electrode 12 due to water or an object containing a lot of moisture. As a countermeasure, in the electrode unit 10 according to this example, the upper and lower ends of the insulator 13 are made to protrude further than the upper and lower ends of the transmitting electrode 11 and the shield electrode 12. This makes it possible to effectively prevent the transmitting electrode 11 and the shield electrode 12 from being electrically connected via water while suppressing an increase in cost due to the countermeasure.

[0042] Figure 9 shows another example of how to install the electrode unit, where Figure 9(a) shows the state in which the rear door is fully open, and Figure 9(b) shows the state in which the rear door is about 1 / 3 open. 9(a), the electrode unit 10 functions as an emergency stop plate 4b, and the worker 6 can bring the loading device to an emergency stop by displacing the electrode unit 10 forward with his knee or the like. By providing the electrode unit 10 and the emergency stop plate 4b integrally in this way, it is possible to suppress an increase in the number of parts and costs due to the provision of the electrode unit 10. The electrode unit 10 shown in FIG. 9(b) has a transmitting electrode 11 that functions as a reflector 7 that reflects light from behind the vehicle. A reflector (reflector) 7 is particularly required for large garbage collection vehicles 1, but by integrating the electrode unit 10 and the reflector 7, it is possible to ensure installation space for the reflector 7 and to suppress the increase in the number of parts and costs that would be caused by providing the electrode unit 10. Furthermore, the electrode unit 10 shown in FIG. 9(b) has a shape that is longer in the vertical direction than the electrode unit 10 shown in FIG. 9(a). By increasing the area of ​​the electrode unit 10 in this way, the approach of the worker 6 can be detected with even greater accuracy. [Industrial Applicability]

[0043] The present invention can be used as a safety device for devices such as refuse collection vehicles, scrap processing devices, and crushing devices, which may injure people if they approach them. [Explanation of symbols]

[0044] 1. Refuse collection truck 2 Input box 2a Inlet 2b Push-in plate 2c Rotating plate 3 Storage Box 4 Emergency stop switch 4a Emergency stop button 4b Emergency stop plate 5 tables 6 people (workers) 7 Reflector 10 Electrode section 11 Transmitting electrode 12 Shield electrode 13 Insulators 20 Capacitive Sensor 30 Control Means 40 Alarm means 50 Supports 51 First metal member 52 Second metal member 53 Insulating materials

Claims

1. A safety device for use in a machine with moving parts, comprising: an electrode unit installed on a side close to a person and away from the machine and the moving part; a capacitance sensor that applies a signal to the electrode unit and measures the capacitance between the electrode unit and the machine, which changes depending on the degree of approach of the person to the electrode unit and the degree to which the person who has approached the electrode unit moves a part of their body further toward the machine or the moving part from that position; a control means for using the change in capacitance measured by the capacitance sensor for control; a support having one end fixed to the machine and the other end to which the electrode unit is attached, A safety device characterized in that the support tool has an insulating member that insulates the machine from the electrode portion.

2. 2. The safety device according to claim 1, wherein the control means changes the operating speed of the movable part in stages in proportion to the change in the capacitance.

3. 3. The safety device according to claim 2, wherein the control means stops the moving part when the capacitance exceeds a predetermined value.

4. 4. The safety device according to claim 3, wherein the control means moves the movable part in a direction opposite to the direction of movement before the movable part was stopped when the state in which the capacitance exceeds the predetermined value continues for a predetermined time.

5. 5. The safety device according to claim 1, further comprising an alarm means, wherein the control means causes the alarm means to issue a step-by-step alarm to the person in proportion to the change in capacitance.

6. 6. The safety device according to claim 1, wherein the electrode portion comprises an insulator, a transmitting electrode in contact with one surface of the insulator and to which the signal is applied, and a shield electrode in contact with the other surface of the insulator and which suppresses parasitic capacitance occurring between the transmitting electrode and the machine, and the shield electrode is disposed facing the machine.

7. 7. The safety device according to claim 6, wherein the upper and lower ends of the insulator protrude beyond the upper and lower ends of the transmitting electrode and the upper and lower ends of the shield electrode.

8. A refuse collection vehicle comprising the safety device according to any one of claims 1 to 7.

9. 9. The refuse collection vehicle according to claim 8, wherein the electrode portion is disposed near an inlet through which refuse is thrown.

10. 10. The refuse collection vehicle according to claim 9, wherein the electrode portion functions as an emergency stop plate that, when displaced, brings the operation of the movable portion of the refuse collection vehicle to an emergency stop.

11. 10. A refuse collection vehicle according to claim 8, wherein the electrode portion functions as a reflector that reflects light from behind the vehicle.

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