Safety band use state confirmation system

Abstract

To provide a safety band use state confirmation system capable of confirming a use state as to whether a hook of a safety band is used in a dangerous area.SOLUTION: A safety band use state confirmation system includes: an IC tag 2 that is attached to a safety band 1 or an accessory of the safety band 1; first trigger signal transmission means 3 that is installed at an entrance part of a dangerous area Z1 and transmits a first trigger signal 31; and second trigger signal transmission means 4 that is installed at a safety region Z2 communicating with the entrance part of the dangerous area Z1 and transmits a second trigger signal 41. The IC tag 2 has a detection function of detecting a use state as to whether or not a hook of the safety band 1 is used, and a transmission function of transmitting a use state signal representing the detected use state. When receiving the first trigger signal 31, the IC tag 2 enters an on-mode in which the detection function and the transmission function are activated. When receiving the second trigger signal 41, the IC tag 2 enters an off-mode in which at least one of the detection function and the transmission function is not activated.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a safety belt use status confirmation system for confirming whether or not a hook of a safety belt is being used in a dangerous area. [Background technology]

[0002] When working in dangerous areas such as high-altitude work areas or pit areas, workers are required to wear safety harnesses to prevent falls, etc. The safety harness comprises a belt worn around the worker's body, a lifeline connected to the belt, and a hook attached to the end of the lifeline. Workers ensure safety when working in dangerous areas by wearing the belt around their body and attaching the hook to a lifeline or similar installed in the dangerous area.

[0003] In order to reliably prevent accidents such as falls, it is necessary for workers to use safety harnesses correctly. In particular, since workers sometimes forget to fasten the hook to the lifeline or the like in dangerous areas, mechanisms have been proposed for checking whether the hook is fastened to the lifeline or the like, i.e., whether the hook is in use.

[0004] For example, Patent Document 1 proposes a "safety belt hook fastening / detachment confirmation system that can detect whether the hook is fastened to the hook holder and issue an alarm if it is fastened to a safety belt comprising a belt worn on the body of a worker, a lifeline connected to the belt, a hook attached to the end of the lifeline, and a hook holder for fastening the hook to the belt, wherein the system comprises means for defining a high-altitude work area in the workplace, means for detecting whether the worker is within the high-altitude work area is attached to the safety belt, and the alarm is issued only when the worker is within the high-altitude work area, and the means for defining the high-altitude work area defines the high-altitude work area using an AC induction magnetic field." [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Patent No. 7378134 Summary of the Invention [Problem to be solved by the invention]

[0006] In the system of Patent Document 1, an AC induction magnetic field is transmitted by an AC induction magnetic field transmitting means installed at a high-altitude work site as a means for defining the high-altitude work area, thereby defining the high-altitude work area. However, it is not always easy to cover and define danger areas such as high-altitude work areas and pit areas using the AC induction magnetic field transmitted by the AC induction magnetic field transmitting means. For example, if the danger area is large, multiple AC induction magnetic field transmitting means must be installed. Furthermore, if the danger area has an irregular shape, such as extending long in a specific direction, it is difficult to cover and define the danger area with the AC induction magnetic field transmitted by the AC induction magnetic field transmitting means. In this way, it may be difficult to cover and define the danger area with the AC induction magnetic field transmitted by the AC induction magnetic field transmitting means, and in such cases, it is not possible to determine whether or not a worker wearing a safety belt is in the danger area, and as a result, it becomes difficult to confirm the usage status, i.e., whether or not the hook of the safety belt is being used in the danger area.

[0007] The problem to be solved by the present invention is to provide a safety belt use status confirmation system that can confirm the use status of a safety belt, ie, whether or not the hook of the safety belt is being used in a dangerous area. [Means for solving the problem]

[0008] According to one aspect of the present invention, the following safety belt use status confirmation system is provided. A safety belt use status confirmation system that confirms the use status of a safety belt hook, An IC tag attached to a safety belt or its accessories; a first trigger signal transmitting means that is installed at an entrance to the dangerous area and that transmits a first trigger signal; a second trigger signal generating means that is installed in a safety area leading to an entrance of the danger area and that generates a second trigger signal; The safety belt use status confirmation system is characterized in that the IC tag has a function of receiving the first trigger signal and a function of receiving the second trigger signal, a detection function of detecting the use status, i.e., whether or not the hook of the safety belt is being used, and a transmission function of transmitting a use status signal representing the detected use status, and further, when the first trigger signal is received, the IC tag goes into an on mode in which the detection function and the transmission function are functional, and when the second trigger signal is received, the IC tag goes into an off mode in which at least one of the detection function and the transmission function is not functional. [Effects of the Invention]

[0009] According to the safety belt use state confirmation system of the present invention, it is possible to confirm the use state of whether or not the hook of the safety belt is being used in a dangerous area. [Brief explanation of the drawings]

[0010] [Figure 1] 1 is a conceptual diagram of a safety belt use state confirmation system according to an embodiment of the present invention; [Figure 2] 1 is a schematic diagram of a safety belt constituting a safety belt use state confirmation system according to embodiment A of the present invention. [Figure 3] FIG. 3 is a perspective view of a hook holder portion of the safety belt of FIG. 2. [Figure 4] 3 is a perspective view of the main part showing a state in which the hook of the safety belt of FIG. 2 is hung on a hook holder. FIG. [Figure 5] A block diagram showing the configuration of the IC tag attached to the hook holder part of the safety belt in Figure 2. [Figure 6] FIG. 10 is a conceptual diagram of a main part of a safety belt use state confirmation system according to embodiment B of the present invention. [Figure 7] FIG. 7 is a block diagram showing an example of the configuration of the IC tag in FIG. 6. [Figure 8] FIG. 10 is a conceptual diagram of a main part of a safety belt use state confirmation system according to embodiment C of the present invention. [Figure 9] FIG. 10 is a schematic diagram of the main parts of the safety belt used in embodiment C. [Figure 10] FIG. 9 is a block diagram showing an example of the configuration of the IC tag in FIG. 8. DETAILED DESCRIPTION OF THE INVENTION

[0011] A safety belt use status confirmation system according to an embodiment of the present invention is conceptually shown in Figure 1. The safety belt use detection system shown in the figure comprises an IC tag 2 attached to a safety belt 1 worn by a worker or its accessories, a first trigger signal emitting means 3 installed at the entrance to a danger zone Z1 and emitting a first trigger signal 31, and a second trigger signal emitting means 4 installed at a safety zone Z2 leading to the entrance to the danger zone Z1 and emitting a second trigger signal 41.

[0012] Although details will be described later, the IC tag 2 has a function to receive a first trigger signal 31 and a function to receive a second trigger signal 41, a detection function to detect the usage state, i.e., whether or not the hook of the safety belt 1 is in use, and a transmission function to transmit a usage state signal indicating the detected usage state, and is further characterized in that when the first trigger signal 31 is received, the IC tag 2 goes into an on mode in which the detection function and the transmission function are functional, and when the second trigger signal 41 is received, the IC tag 2 goes into an off mode in which at least one of the detection function and the transmission function is not functional.

[0013] Since the IC tag 2 is attached to the safety belt 1 worn by the worker or its accessories, when the IC tag 2 receives the first trigger signal 31, it can be assumed that the worker is in the danger zone Z1, and on the other hand, when the IC tag 2 receives the second trigger signal 41, it can be assumed that the worker is in the safety zone Z2. When the IC tag 2 receives the first trigger signal 31, it goes into the on mode in which the detection function and the transmission function are functioning, and when it receives the second trigger signal 41, it goes into the off mode in which at least one of the detection function and the transmission function is not functioning, so that when the worker is in the danger zone Z1, i.e., in the danger zone Z1, it can be confirmed whether the hook of the safety zone 1 is being used or not.

[0014] The IC tag 2 can include an alarm unit that receives the use status signal transmitted by the transmission function and outputs an alarm when the received use status signal indicates that the hook is not in use.

[0015] The safety belt use status confirmation system may further include an alarm 5 installed in the danger zone Z1 as shown in Fig. 1. This alarm 5 receives the use status signal transmitted by the transmitting function, and outputs an alarm when the received use status signal indicates that the hook is not in use.

[0016] 1, the safety belt use status confirmation system can further include a signal receiving means 6 that receives the use status signal transmitted by the transmission function. The signal receiving means 6 can have the function of transmitting the received use status signal directly to an external management computer (not shown), and can also have the function of determining the use status, whether the hook of the safety belt 1 is in use, from the received use status signal and transmitting the determined information to the external management computer (not shown). Furthermore, the signal receiving means 6 can also have the function of the alarm 5. That is, the signal receiving means 6 can also have the function of receiving the use status signal transmitted by the transmission function and outputting an alarm when the received use status signal indicates that the hook is not in use. In this case, the signal receiving means 6 also functions as the alarm 5, and a separate alarm 5 is not required. The signal receiving means 6 can directly receive the use status signal transmitted by the transmission function, or can receive it via a mobile terminal or the like.

[0017] As can be seen from the above explanation, the transmission function in the present invention collectively refers to the function of transmitting the usage status signal to, for example, the alarm unit inside the IC tag, and the function of transmitting the usage status signal to the outside of the IC tag (for example, the alarm device 5 and signal receiving means 6).

[0018] Below, a more specific embodiment will be described, focusing on the functions of the IC tag. Note that in the following explanation, a specific explanation of the first trigger signal emitting means 3 and the second trigger signal emitting means 4 shown in Fig. 1 will be omitted, but it is assumed that the first trigger signal emitting means 3 emits a first induced magnetic field as a first trigger signal 31, and the second trigger signal emitting means 4 emits a second induced magnetic field as a second trigger signal 41.

[0019] <Embodiment A> Fig. 2 shows a safety belt 1A constituting the safety belt usage status confirmation system of embodiment A. The safety belt 1A includes a belt 11A worn around the worker's body, a lifeline 12A connected to the belt 11A, a hook 13A attached to the end of the lifeline 12A, and a hook holder 14A for hanging the hook 13A on the belt 11A. In this embodiment, the hook holder 14A is formed in a hook holder portion 15A, and an IC tag 2A is attached to this hook holder portion 15A as shown in Fig. 3. In this embodiment, a magnet 16A is attached to the hook 13A. As shown in Figure 4, hook 13A is normally (before use) hung on hook holder 14A. When hook 13A is hung on hook holder 14A, magnet 16A attached to hook 13A is positioned near hook holder 14A.

[0020] The configuration of the IC tag 2A is shown in a block diagram in Figure 5. The IC tag 2A is installed near the hook holder 14A and includes a magnetic sensor as a means for detecting the magnetic field of the magnet 16A, a warning means, a display means, an AC induction magnetic field receiving means, a transmission circuit and an antenna, a tag control means for controlling these, and a battery.

[0021] When the magnetic sensor detects magnetism, the tag control means determines that the hook 13A is hung on the hook holder 14A, and further determines based on this determination that the usage state of the hook 13A is "hook not in use." When the magnetic sensor does not detect magnetism, the tag control means determines that the hook 13A is not hung on the hook holder 14A, and further determines based on this determination that the usage state of the hook 13A is "hook in use." That is, in this embodiment, the tag control means and the magnetic sensor of the IC tag 2A work together to perform the detection function of detecting the usage state of whether or not the hook 13A of the safety belt 1A is in use.

[0022] The detected use state is transmitted as radio waves containing a use state signal indicating the use state (hook in use or not in use) together with the unique identification number of the IC tag 2A via the transmission circuit and antenna. The use state signal is also transmitted from the tag control means to the warning means and display means, which are the alarm unit. That is, in this embodiment, the tag control means, transmission circuit, and antenna of the IC tag 2A work together to perform the transmission function of transmitting a use state signal indicating the use state, whether or not the hook 13A of the safety belt 1A is in use.

[0023] The AC induction magnetic field receiving means receives the first induction magnetic field as the first trigger signal 31 transmitted by the first trigger signal transmitting means 3 shown in Fig. 1 and the second induction magnetic field as the first trigger signal 41 transmitted by the second trigger signal transmitting means 4. That is, in this embodiment, the AC induction magnetic field receiving means performs the function of receiving the first trigger signal 31 and the function of receiving the second trigger signal 41.

[0024] When the AC induction magnetic field receiving means receives the first trigger signal 31, the tag control means determines that the worker wearing the safety belt 1A is in a dangerous area, and sets the IC tag 2A in an on mode in which the detection function and the transmission function are functional. On the other hand, when the AC induction magnetic field receiving means receives the second trigger signal 41, the tag control means determines that the worker wearing the safety belt 1A is in a safe area, and sets the IC tag 2A in an off mode in which at least one of the detection function and the transmission function is not functional.

[0025] In the IC tag 2A, the warning means and display means are an alarm unit that receives the use status signal transmitted by the transmission function and outputs an alarm when the received use status signal indicates that the hook is not in use. In this embodiment, the alarm is output as sound from the warning means and as light from the display means.

[0026] <Embodiment B>

[0027] Fig. 6 conceptually shows the main parts of the safety belt use status confirmation system of embodiment B. The safety belt use status confirmation system shown in the figure comprises a long main rope 7, a hook 11B to which a safety belt 1B is attached via a lifeline 12B, an IC tag 2B attached to the hook 11B, and a long trigger signal emitting means (hereinafter referred to as "third trigger signal emitting means") 8 that is provided on the main rope 7 and emits a trigger signal (hereinafter referred to as "third trigger signal") 81 of the IC tag 2B.

[0028] In this embodiment, the IC tag 2B is attached to the tip of the hook 11B of the safety belt 1B. As a result, when the hook 11B is hung on the main rope 7, as shown in Figure 6, the IC tag 2B is reliably positioned near the main rope 7.

[0029] In this embodiment, the third trigger signal transmitting means 8 includes a long U-shaped conductor built into the main rope 7 along its longitudinal direction, and transmits a third trigger signal 81 so as to extend over an area adjacent to the main rope 7. In this embodiment, the third trigger signal 81 is transmitted as an AC induced magnetic field. This AC induced magnetic field is transmitted when an AC current applied by a transmitter 82 shown in FIG. 6 flows through the conductor.

[0030] The configuration of the IC tag 2B is shown in a block diagram in Figure 7. The IC tag 2B includes a magnetic field sensor unit that detects the AC induction magnetic field, which is the third trigger signal, a radio wave transmitter unit, an alarm unit, a control unit that controls these, and a battery as a power source.

[0031] In this embodiment, when the magnetic field sensor unit detects an AC induced magnetic field, which is the third trigger signal, the control unit determines that the hook 11B is hooked on the master rope 7, and further determines based on this determination that the usage state of the hook 11B is "hook in use." When the magnetic field sensor unit does not detect an AC induced magnetic field, which is the third trigger signal, the control unit determines that the hook 11B is not hooked on the master rope 7, and further determines based on this determination that the usage state of the hook 11B is "hook not in use." In other words, in this embodiment, the control unit and magnetic field sensor unit of the IC tag 2B work together to perform the detection function of detecting the usage state, i.e., whether or not the hook 13A of the safety belt 1B is in use.

[0032] The detected use state is transmitted as radio waves including a use state signal indicating the use state (hook in use or not in use) together with the unique identification number of the IC tag 2A via the radio wave transmitting unit. The use state signal is also transmitted from the control unit to the alarm unit. That is, in this embodiment, the control unit and radio wave transmitting unit of the IC tag 2B cooperate to perform the transmitting function of transmitting a use state signal indicating the use state, whether the hook 11B of the safety belt 1B is in use or not.

[0033] In the IC tag 2B, the magnetic field sensor unit receives a first induced magnetic field as a first trigger signal 31 transmitted by the first trigger signal transmitting means 3 shown in Fig. 1, and a second induced magnetic field as a first trigger signal 41 transmitted by the second trigger signal transmitting means 4. That is, in this embodiment, the magnetic field sensor unit also performs the function of receiving the first trigger signal 31 and the function of receiving the second trigger signal 41.

[0034] In this embodiment, when the magnetic field sensor unit receives the first trigger signal 31, the control unit of the IC tag 2B determines that the worker wearing the safety belt 1B is in a dangerous area, and sets the IC tag 2B to an ON mode in which the detection function and the transmission function are functioning. On the other hand, when the magnetic field sensor unit receives the second trigger signal 41, the control unit determines that the worker wearing the safety belt 1B is in a safe area, and sets the IC tag 2B to an OFF mode in which at least one of the detection function and the transmission function is not functioning.

[0035] The alarm section of the IC tag 2B receives the use status signal transmitted by the transmission function, and outputs an alarm when the received use status signal indicates that the hook is not in use.

[0036] Furthermore, the safety belt use status confirmation system of this embodiment is equipped with a signal receiving means 6B that receives the use status signal transmitted by the transmission function. The signal receiving means 6B can have the function of transmitting the received use status signal directly to an external management computer (not shown), and can also have the function of determining the use status, whether or not the hook 11B of the safety belt 1B is in use, from the received use status signal and transmitting the determined information to the external management computer (not shown). Furthermore, the signal receiving means 6B can also have the function of an alarm. That is, the signal receiving means 6B can have the function of receiving the use status signal transmitted by the transmission function and outputting an alarm when the received use status signal indicates that the hook is not in use. The signal receiving means 6B can directly receive the use status signal transmitted by the transmission function, or can receive it via a mobile terminal or the like.

[0037] In this embodiment, the safety belt 1B is equipped with one hook 11B, but it may also be equipped with two hooks. In this case, an IC tag is attached to each hook, and the usage status of each hook can be detected. The signal receiving means 6B receives a usage status signal for each hook indicating whether the hook is in use or not, and comprehensively determines the usage status of the hook based on each usage status signal. For example, if all usage status signals indicate that the hook is not in use, it can be determined that the hook is not in use and an alarm can be output. Alternatively, if any one usage status signal indicates that the hook is not in use, it can be determined that the hook is not in use and an alarm can be output. The signal receiving means 6B can also transmit the usage status of these hooks and the determination results to an external management computer (not shown).

[0038] <Embodiment C> In the previous embodiments A and B, an IC tag is attached to a safety belt, but in this embodiment, an IC tag is attached to an accessory to the safety belt. Fig. 8 conceptually shows the main parts of the safety belt use state confirmation system of embodiment C. Fig. 9 also shows the main parts of the safety belt used in embodiment C. In this embodiment, a hook lock detection item 9 is used as an accessory to the safety belt 1C to detect whether or not the hook 11C of the safety belt 1C is hooked on the life rope 7, and an IC tag 2C is attached to this hook lock detector 9. The hook lock detector 9 is an item that a worker wearing the safety belt 1C carries with him when heading towards a danger area. In other words, the accessory to the safety belt is an item that a worker wearing the safety belt carries with him when heading towards a danger area.

[0039] As shown in Figure 8, the hook engagement detection item 9 includes an item main body 91 that is detachably installed so as to surround the periphery of the master rope 7. This item main body 91 can move freely along the laying direction of the master rope 7 (horizontal in this embodiment), and has a shape that clamps both sides of the hook 11C when the hook 11C is hung on the master rope 7. Specifically, the item main body 91 includes a shutter 911, and when the item main body 91 is attached to or detached from the master rope 7, the shutter 911 is in a raised state, and when the hook 11C is hung on the master rope 7, the shutter 911 is in a lowered state. The center of gravity of the item main body 91 is set so that when installed so as to surround the periphery of the master rope 7, it assumes the posture shown in Figure 8.

[0040] An IC tag 2C is attached to the article main body 91 in order to detect the presence of the hook 11C when the hook 11C is hung on the main rope 7. In this embodiment, a magnet 13C is attached to the hook 11C, and the IC tag 2C detects the presence of the hook 11C by detecting the magnetism of the magnet 13C. Therefore, when the hook 11C is hung on the main rope 7, the magnet 13C attached to the hook 11C is positioned in the vicinity of the IC tag 2C.

[0041] The configuration of tag 2C is shown in a block diagram in Figure 10. Tag 2C has a magnetic sensor as a means for detecting the magnetic field of magnet 13C, a warning means, a display means, an AC induction magnetic field receiving means, a transmission circuit and an antenna, a tag control means for controlling these, and a battery.

[0042] When the magnetic sensor detects magnetism, the tag control means determines that the hook 11C is present, i.e., that the hook 11C is hooked on the main rope 7, and further determines based on this determination that the usage status of the hook 11C is "hook in use." Also, when the magnetic sensor does not detect magnetism, the tag control means determines that the hook 11C is not present, i.e., that the hook 11C is not hooked on the main rope 7, and further determines based on this determination that the usage status of the hook 11C is "hook not in use."

[0043] The detected use state is transmitted as radio waves containing a use state signal indicating the use state (hook in use or not in use) together with the unique identification number of the IC tag 2A via the transmission circuit and antenna. The use state signal is also transmitted from the tag control means to the warning means and display means, which are the alarm unit. That is, in this embodiment, the tag control means, transmission circuit, and antenna of the IC tag 2C work together to perform the transmission function of transmitting a use state signal indicating the use state, whether the hook 11C of the safety belt 1C is in use or not.

[0044] The AC induction magnetic field receiving means receives the first induction magnetic field as the first trigger signal 31 transmitted by the first trigger signal transmitting means 3 shown in Fig. 1 and the second induction magnetic field as the first trigger signal 41 transmitted by the second trigger signal transmitting means 4. That is, in this embodiment, the AC induction magnetic field receiving means performs the function of receiving the first trigger signal 31 and the function of receiving the second trigger signal 41.

[0045] When the AC induction magnetic field receiving means receives the first trigger signal 31, the tag control means determines that the worker wearing the safety belt 1C is in a dangerous area, and sets the IC tag 2C in an on mode in which the detection function and the transmission function are functional. On the other hand, when the AC induction magnetic field receiving means receives the second trigger signal 41, the tag control means determines that the worker wearing the safety belt 1C is in a safe area, and sets the IC tag 2C in an off mode in which at least one of the detection function and the transmission function is not functional.

[0046] In the IC tag 2C, the warning means and display means are an alarm unit that receives the use status signal transmitted by the transmission function and outputs an alarm when the received use status signal indicates that the hook is not in use. In this embodiment, the alarm is output as sound from the warning means and as light from the display means.

[0047] In the embodiments A to C, an AC induction magnetic field is used as the trigger signal, but other than the AC induction magnetic field, for example, an electric wave can also be used as the trigger signal. In addition, in the embodiments A to C, a high-altitude work area is assumed as a dangerous area, but the dangerous area is not limited to a high-altitude work area, and for example, a pit area leading to an underground structure also falls under the dangerous area. In short, a dangerous area is an area where the use of a safety harness is required. 1 shows a case where the danger area and the safety area are at different height levels, but the danger area and the safety area may be at the same height level. In this case, the first trigger signal transmitting means may be installed at the entrance to the danger area, and the first trigger signal transmitting means may be installed in the safety area leading to the entrance to the danger area. [Explanation of symbols]

[0048] 1 Safety harness 1A Safety Belt 11A Belt 12A Lifeline 13A Hook 14A Hook holder 15A Hook holder part 16A magnet 1B Safety belt 11B hook 12B Lifeline 1C Safety belt 11C Hook 12C Lifeline 13C magnet 2, 2A, 2B, 2C IC tags 3. First trigger signal transmission means 31 First Trigger Signal 4. Second trigger signal generating means 41 Second trigger signal 5 alarm 6, 6A Signal Receiving Means 7. Main rope 8. Third trigger signal generating means 81 Third Trigger Signal 9 Hook-locking detection items 91 Item itself 911 shutter Z1 Danger Zone Z2 safety area

Claims

1. A safety belt use status confirmation system that confirms the use status of a safety belt hook, An IC tag attached to a safety belt or its accessories; a first trigger signal transmitting means that is installed at an entrance to the dangerous area and that transmits a first trigger signal; a second trigger signal generating means that is installed in a safety area leading to an entrance of the danger area and that generates a second trigger signal; The safety belt use status confirmation system is characterized in that the IC tag has a function of receiving the first trigger signal and a function of receiving the second trigger signal, a detection function of detecting the use status of whether or not the hook of the safety belt is in use, and a transmission function of transmitting a use status signal representing the detected use status, and further, when the first trigger signal is received, the IC tag goes into an on mode in which the detection function and the transmission function are functional, and when the second trigger signal is received, the IC tag goes into an off mode in which at least one of the detection function and the transmission function is not functional.

2. 2. The safety belt use status confirmation system according to claim 1, wherein the IC tag includes an alarm unit, the alarm unit receives the use status signal transmitted by the transmission function, and outputs an alarm when the received use status signal indicates that the hook is not in use.

3. 3. The safety belt use status confirmation system according to claim 1, further comprising an alarm device installed in a dangerous area, wherein the alarm device receives the use status signal transmitted by the transmitting function, and outputs an alarm when the received use status signal indicates that the hook is not in use.

4. 3. The safety belt use state confirmation system according to claim 1, further comprising a signal receiving means for receiving the use state signal transmitted by said transmitting function.

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