Alarm device and alarm sounding method

Abstract

To provide an alarm device capable of shortening a difference between a time at which an alarm condition is satisfied and a time at which an alarm is actually issued, compared to a conventional alarm device, when a plurality of alarms are issued in order.SOLUTION: An alarm device 1 includes an acquisition unit 3 that acquires a plurality of types of safety information 20 that are information related to safety of a vehicle 22, and an alarm unit 5 that determines whether or not a plurality of alarm conditions are satisfied based on the safety information 20 and, when it is determined that the plurality of alarm conditions are satisfied, issues alarms corresponding to the plurality of alarm conditions in order from an alarm having an earlier time at which it is determined that the alarm conditions are satisfied, and the alarm device 1 is mounted on the vehicle 22, and the safety information 20 includes information indicating a first time that is a time at which the safety information 20 is generated or transmitted / received, and the alarm unit 5 acquires a current time when an order of issuing an alarm corresponding to one of a plurality of alarm conditions comes, and does not issue an alarm corresponding to one of the alarm conditions when a time difference between the first time and the current time of the safety information 20 serving as a basis of determining that one of the alarm conditions is satisfied is equal to or larger than a time threshold.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to an alarm device and an alarm sounding method. [Background technology]

[0002] Some vehicle-mounted devices, such as drive recorders, can sound various alarms to call attention to improve safety while driving. For example, a safety system is known that receives identification signals emitted by tags carried by workers around the vehicle to determine the distance between the vehicle and the worker, and issues a warning sound or voice alert to the vehicle crew when the distance is within a predetermined value, thereby preventing contact between the vehicle and the worker (Patent Document 1). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Publication No. 2020-125171 Summary of the Invention [Problem to be solved by the invention]

[0004] However, when there are multiple conditions for issuing an alarm, the technology for issuing an alarm using a warning sound or voice, as in Patent Document 1, cannot issue alarms corresponding to multiple conditions simultaneously. Instead, when multiple conditions are met, the alarms must be issued one by one in order. Therefore, the later the alarm is issued, the later the alarm is issued from the time the alarm condition is met. For example, when an alarm is to be issued when the distance between a vehicle and a worker is within a predetermined distance, if the alarm is issued too late compared to the time the distance becomes within the predetermined distance, the alarm may be issued after the worker has moved away from the vehicle and exceeded the predetermined distance. In this case, the alarm is issued even if there is no worker near the vehicle. As a result, the alarm is issued too late to the vehicle crew, making it impossible to take measures to improve safety during driving.

[0005] The present invention has been made to solve such problems, and its purpose is to provide an alarm device and an alarm sounding method that, when multiple alarms are sounded in sequence, can shorten the time between the time when the alarm conditions are met and the time when the alarm is actually sounded, compared to conventional methods. [Means for solving the problem]

[0006] The warning device of the present invention comprises an acquisition unit that acquires multiple types of safety information that is information related to the safety of the vehicle, and an alarm unit that determines whether multiple predetermined warning conditions are met based on the safety information, and if it is determined that the conditions are met, issues warnings corresponding to the multiple warning conditions in order, starting with the warning that was determined to satisfy the warning conditions earliest.The warning device is mounted on the vehicle, and the safety information includes information indicating a first time, which is the time at which the safety information was generated or transmitted / received, and the alarm unit acquires the current time when it is its turn to issue the warning corresponding to one of the multiple warning conditions, and if the time difference between the first time in the safety information, which is the basis for determining that one of the warning conditions is met, and the current time, is equal to or greater than a predetermined time threshold, the warning corresponding to one of the warning conditions is not issued.

[0007] The alarm sounding method of the present invention comprises an acquisition unit that performs an acquisition process of acquiring multiple types of safety information that is information related to the safety of the vehicle, and an alarm unit that performs an alarm process of determining whether multiple predetermined alarm conditions are met based on the safety information, and if it is determined that the safety information is met, issuing alarms corresponding to the multiple alarm conditions in order starting with the alarm that was determined to satisfy the alarm conditions earliest, and is a method of sounding an alarm for an alarm device mounted on the vehicle, wherein the safety information includes information indicating a first time, which is the time at which the safety information was generated or transmitted / received, and in the alarm process, when it is the turn to issue the alarm corresponding to one of the multiple alarm conditions, the current time is acquired, and if the time difference between the first time in the safety information, which is the basis for determining that one of the alarm conditions is met, and the current time, is equal to or greater than a predetermined time threshold, the alarm corresponding to one of the alarm conditions is not issued. [Effects of the Invention]

[0008] According to the present invention, when multiple alarms are issued in sequence, the time difference between the time when the alarm conditions are satisfied and the time when the alarm is actually issued can be made shorter than in the past. [Brief explanation of the drawings]

[0009] [Figure 1] 1 is a configuration diagram showing an alarm device according to an embodiment of the present invention; [Figure 2] FIG. 10 is a diagram showing distance information and acceleration information. [Figure 3] FIG. 10 is a diagram for explaining a procedure for calculating the distance between the vehicle and workers around the vehicle. [Figure 4] 10 is a diagram showing the relationship between the RSSI (Received Signal Strength Indicator) of a signal emitted by a beacon and the distance between a vehicle and the beacon. FIG. [Figure 5] 10A and 10B are diagrams showing the relationship between time, the timing of sending and receiving a signal from a beacon, and the timing of sounding an alarm, where (a) is an example of this embodiment, (b) is an example of the prior art, and (c) is another example of this embodiment. [Figure 6] FIG. 10 is a diagram showing priority order information. [Figure 7] 1 is a flowchart showing an outline of the procedure of an alarm sounding method using an alarm device according to an embodiment of the present invention. [Figure 8] 8 is a flowchart for sounding a human approach alarm in FIG. 7. DETAILED DESCRIPTION OF THE INVENTION

[0010] The present invention will be described below in accordance with preferred embodiments. Note that the present invention is not limited to the embodiments shown below and can be modified as appropriate without departing from the spirit of the present invention. In addition, in the embodiments shown below, some components are omitted from illustration and description, but it goes without saying that publicly known or well-known technologies are applied as appropriate to the details of the omitted technologies within the scope of the content described below.

[0011] First, with reference to FIGS. 1 to 6, an outline of the configuration of an alarm device according to an embodiment of the present invention will be described. FIG. 1 is a configuration diagram showing an alarm device according to an embodiment of the present invention. FIG. 2 is a diagram showing distance information and acceleration information. FIG. 3 is a diagram for explaining a procedure for calculating the distance between the vehicle and a worker around the vehicle. FIG. 4 is a diagram showing the relationship between the RSSI of a signal emitted by a beacon and the distance between the vehicle and the beacon. FIG. 5 is a diagram showing the relationship between time, the timing of transmission and reception of a signal from a beacon, and the timing of sounding an alarm, where (a) is an example of this embodiment, (b) is an example of the prior art, and (c) is another example of this embodiment. FIG. 6 is a diagram showing priority information. The alarm device 1 shown in FIG. 1 is mounted on a vehicle 22, such as a forklift, as the host vehicle, and includes an acquisition unit 3 and an alarm unit 5. The alarm device 1 shown in FIG. 1 also includes a power supply unit 12.

[0012] The acquisition unit 3 acquires multiple types of safety information 20, which is information related to the safety of the vehicle 22, and in FIG. 1 includes a first acquisition unit 3a and a second acquisition unit 3b. The first acquisition unit 3a acquires distance information 23 (safety information) shown in FIGS. 1 and 2 as one of the multiple types of safety information 20. The distance information 23 is information indicating the distance between the beacon 11 and the alarm device 1 shown in FIGS. 1 and 3, and in this case, is radio waves emitted by the beacon 11. As shown in FIG. 3, this embodiment illustrates a case in which the alarm device 1 is mounted on the vehicle 22 and the worker 31 (pedestrian) carries the beacon 11, so the distance information 23 is information indicating the distance between the worker 31 and the vehicle 22.

[0013] The beacon 11 shown in FIG. 1 includes a transmitter 11a, a time setting unit 11b, and a battery 11c. The transmitter 11a generates distance information 23 at predetermined time intervals and transmits it to the first acquisition unit 3a. The time setting unit 11b sets first time information 23b (information indicating a first time) to the distance information 23 when the distance information 23 is generated. Therefore, as shown in FIG. 2, the distance information 23 includes the first time information 23b. The first time information 23b is information indicating a first time, which is the time when the distance information 23 is generated or transmitted / received, and in this embodiment, it is information (a timestamp value) indicating the generation time when the distance information 23 is generated. The battery 11c is a power source that operates the transmitter 11a and the time setting unit 11b.

[0014] The first acquisition unit 3a shown in FIG. 1 includes a receiving unit 10a and a measuring unit 10b. The receiving unit 10a receives distance information 23. The measuring unit 10b calculates the distance between the vehicle 22 and the worker 31 from the distance information 23 received by the receiving unit 10a. Specifically, as shown in FIG. 4, the measuring unit 10b calculates the distance between the beacon 11 and the vehicle 22 from the strength (signal strength) of the radio waves indicating the received distance information 23, and determines this as the distance between the worker 31 and the vehicle 22. Because the distance information 23 is radio waves emitted by the beacon 11, it is attenuated as it propagates through the air. Therefore, the signal strength of the distance information 23 received by the first acquisition unit 3a decreases as the distance between the vehicle 22 and the beacon 11 increases. Conversely, the signal strength of the distance information 23 received by the first acquisition unit 3a increases as the distance between the vehicle 22 and the beacon 11 decreases. 4, if the first acquisition unit 3a stores in advance the correlation between the signal strength of the distance information 23 received by the first acquisition unit 3a and the distance between the vehicle 22 and the beacon 11, the distance between the vehicle 22 and the beacon 11 can be found from the signal strength of the received distance information 23. Also, if a crew member such as a driver of the vehicle 22 carries a beacon 11, when the crew member receives signals from multiple beacons 11 while aboard the vehicle 22, the beacon 11 that is closest to the alarm device 1 will be the beacon 11 carried by the crew member. Therefore, when no signal is received from any beacon 11, the acquisition unit 3 can also determine that no crew member is aboard the vehicle 22.

[0015] The second acquisition unit 3b shown in FIG. 1 acquires acceleration information 21 (safety information) indicating the acceleration of the vehicle 22 from the acceleration sensor 9. As shown in FIG. 2, the acceleration information 21 includes an acceleration acquisition value 21a and first time information 21b (information indicating a first time). The acceleration acquisition value 21a is information indicating the acceleration acquired by the acceleration sensor 9. The first time information 21b is information indicating a first time, which is the time when the distance information 23 is generated or transmitted / received. The acceleration sensor 9 shown in FIG. 1 is a known sensor such as a capacitance type or strain gauge type, and includes a detection unit 9a and a time setting unit 9b. The detection unit 9a detects acceleration to acquire the acceleration acquisition value 21a and transmits acceleration information 21, which is information including the acceleration acquisition value 21a, to the second acquisition unit 3b. If the acceleration sensor 9 is a capacitance type, the detection unit 9a includes an electrode that detects acceleration and acquires it as the acceleration acquisition value 21a, and an output port that transmits the acceleration information 21 including the acceleration acquisition value 21a to the second acquisition unit 3b. The time setting unit 9b sets first time information 21b to the acceleration information 21 when the distance information 23 is generated. The first time information 21b is information indicating the first time, which is the time when the acceleration information 21 is generated or transmitted / received, and in this embodiment, it is information indicating the time when the acceleration acquisition value 21a is generated. Note that while Fig. 1 illustrates a configuration in which the acceleration sensor 9 is provided outside the alarm device 1, the alarm device 1 may have the acceleration sensor 9 built in.

[0016] The alarm unit 5 shown in FIG. 1 issues a corresponding alarm when a predetermined alarm condition is met. Specifically, the alarm unit 5 is a speaker that determines whether the predetermined alarm condition is met based on the safety information 20 and issues an alarm, such as an audio alarm, when it determines that the predetermined alarm condition is met. For example, when the distance between the vehicle 22 and a worker 31 around the vehicle 22 indicated by distance information 23, which is one of the safety information 20, is within a predetermined distance threshold, the alarm unit 5 determines that there is a possibility of contact between the worker 31 and the vehicle 22 and issues an alarm. In the following description, the condition that the distance between the worker 31 and the vehicle 22 indicated by the distance information 23 is within a predetermined distance threshold is referred to as a proximity condition. In the following description, an alarm issued when the proximity condition is met is referred to as a human proximity alarm. A specific example of a human proximity alarm is an audio alarm, such as "There is a person nearby," that notifies the driver of the vehicle 22 that the worker 31 is approaching. Note that such an audio alarm takes time from the start to the end of sounding. Therefore, while the human approach alarm is sounding, the alarm unit 5 does not determine whether the distance between the vehicle 22 and the worker 31 around the vehicle 22, as indicated by the distance information 23, satisfies the approach condition. Furthermore, what is meant here by the distance between the vehicle 22 and the worker 31 around the vehicle 22 being within a predetermined distance threshold, more precisely, means that the position of the vehicle 22 relative to the worker 31 is within the distance threshold.

[0017] For example, as shown in FIG. 5(a), assume that the beacon 11 transmits (transmits) distance information 23 at a predetermined time interval TA. Also, assume that the distance between the vehicle 22 and the worker 31 around the vehicle 22 is within the distance threshold from time t1 to time t5 in FIG. 5(a), satisfying the proximity condition for issuing a human approach alarm. Furthermore, assume that the time when the beacon 11 generates and transmits the distance information 23 is the same. In this case, a time difference ΔT (absolute value) occurs between the time when the distance information 23 is transmitted from the beacon 11 and the time when the alarm device 1 receives the distance information 23. Therefore, the alarm unit 5 starts sounding a human approach alarm at time t2, when the alarm unit 5 receives the distance information 23 indicated by the number "2" in FIG. 5(a) transmitted from the beacon 11 at time t1. In this case, if the alarm is audio, it takes time T1 from the time when the human approach alarm starts sounding at time t2 until it ends sounding at time t3. Therefore, of the distance information 23 transmitted from the beacon 11 between times t2 and t3, the alarm device 1 does not determine whether the distance information 23 indicated by numbers "3," "4," and "5" in FIG. 5(a) satisfies the alarm conditions for a human approach alarm. On the other hand, in FIG. 5(a), the distance between the worker 31 and the vehicle 22 remains within the distance threshold even after time t3 when the alarm stopped sounding, and the distance between the worker 31 and the vehicle 22 indicated by distance information 23 indicated by number "6" satisfies the conditions for issuing a human approach alarm. Therefore, when the alarm device 1 receives the distance information 23 indicated by number "6" at time t4, it determines that the alarm conditions are met and again sounds an alarm for time T1 until time t6. In other words, the alarm unit 5 does not determine whether the alarm conditions corresponding to the alarm currently sounding are met during time T1 while a certain alarm is sounding.

[0018] Furthermore, if the acceleration indicated by the acceleration information 21 exceeds a predetermined acceleration threshold, the alarm unit 5 determines that the vehicle 22 may have engaged in dangerous driving, such as sudden acceleration or deceleration, or may have been involved in a collision accident, and issues an alarm. The condition in which the acceleration indicated by the acceleration information 21 exceeds a predetermined acceleration threshold is hereinafter referred to as an acceleration / deceleration condition. Furthermore, the alarm issued when the acceleration / deceleration condition is satisfied is hereinafter referred to as a sudden acceleration / deceleration alarm. A specific example of a sudden acceleration / deceleration alarm is an audio alarm that notifies the driver of the vehicle 22 that sudden acceleration or deceleration has occurred, such as "This is sudden acceleration / deceleration, please be careful." With such an audio alarm, the time from when the alarm starts to when it ends is determined based on the length of the words.

[0019] In this embodiment, there are multiple alarms (human approach alarm and acceleration / deceleration alarm), and therefore multiple alarm conditions. Therefore, there are cases where multiple alarm conditions are met. For example, if an operator 31 is present within the distance threshold from the vehicle 22 and the vehicle 22 suddenly accelerates or decelerates, two alarm conditions, the approach condition and the acceleration / deceleration condition, are met. When the alarm unit 5 determines that multiple alarm conditions are met, it issues the corresponding alarms in order, starting with the alarm that was determined to satisfy the alarm condition earlier. For example, if the sudden acceleration / deceleration alarm was determined to satisfy the alarm condition earlier than the human approach alarm, the sudden acceleration / deceleration alarm is issued first, and then the human approach alarm is issued after the sudden acceleration / deceleration alarm has been issued. This is because, particularly when issuing alarms by voice, alarms corresponding to different alarm conditions cannot be sounded simultaneously.

[0020] On the other hand, when alarms are issued in order of the time at which the alarm conditions are determined to be met, an alarm for which the alarm conditions are determined to be met later is issued after an alarm for which the alarm conditions are determined to be met earlier has finished sounding. Therefore, the actual time at which an alarm is issued is delayed from the time at which the alarm conditions are determined to be met. For example, in FIG. 5(b), at time t3, the distance between the vehicle 22 and the worker 31 around the vehicle 22 is within the distance threshold, satisfying the condition for issuing a human proximity alarm. Therefore, the distance information 23 (number "6" in FIG. 5) transmitted by the beacon 11 at time t3 becomes safety information 20 indicating that the condition for issuing a human proximity alarm is met. The alarm device 1 receives this distance information 23 at time t4, but in FIG. 5(b), it also receives acceleration information 21 indicating that sudden acceleration / deceleration occurred at time tc, before time t4. Therefore, the alarm unit 5 of the alarm device 1 first sounds the sudden acceleration / deceleration alarm for which the alarm conditions are determined to be met earlier. If this alarm sounds for a time T2, in the prior art, a human approach alarm sounds at time t7 when the alarm finishes sounding. Therefore, the time t7 when the human approach alarm actually sounds is delayed by a time difference T3 from the time t3 when the distance information 23 (number "6" in FIG. 5(b)) that serves as the basis for satisfying the approach condition is generated and transmitted. However, at time t7, the distance between the vehicle 22 and the worker 31 around the vehicle 22 is not within the distance threshold. Therefore, the human approach alarm is issued even though the worker 31 has moved away from the vehicle 22, and the crew of the vehicle 22 feels that the alarm is delayed.

[0021] Therefore, in this embodiment, when it is the alarm unit 5's turn to issue an alarm corresponding to one of the alarm conditions, the alarm unit 5 performs the following process. First, it acquires the current time at the time when it is its turn to issue an alarm. For example, in FIG. 5C, at time t2, the alarm unit 5 determines that the approach condition is satisfied, but the other alarm conditions are not satisfied, and it is its turn to issue an alarm. Therefore, it acquires time t2 as the current time. On the other hand, the alarm unit 5 determines that the approach condition is satisfied at time t4, but determines that the acceleration / deceleration condition is satisfied at time tc. Therefore, it first sounds the sudden acceleration / deceleration alarm for which it determined that the alarm condition was satisfied earlier. Therefore, even if the alarm unit 5 determines that the approach condition is satisfied at time t4, it is not its turn to issue a human approach alarm until time t7. Therefore, at time t7, the alarm unit 5 acquires time t7 as the current time. Next, the alarm unit 5 determines whether the time difference between the generation time (first time) of the safety information 20, which is the basis for determining that one of the alarm conditions is satisfied, and the current time is equal to or greater than a predetermined time threshold Th. If the time is equal to or greater than the time threshold Th, the corresponding alarm is not issued. If the time is less than the time threshold Th, the corresponding alarm is issued. For example, at time t2, the alarm unit 5 calculates the time difference T4 between time t1, which is the time when the safety information 20 (number "2" in FIG. 5(c)) was generated, which is the basis for determining that one of the alarm conditions is met, and time t2, which is the current time. In this case, the time difference T4 is less than the time threshold Th, so the alarm unit 5 issues a human approach alarm corresponding to the approach condition at time t2. On the other hand, when it is the alarm unit 5's turn to issue a human approach alarm at time t7, the alarm unit 5 calculates the time difference T3 between time t3, which is the time when the safety information 20 (number "6" in FIG. 5(c)) was generated, which is the basis for determining that the approach condition is met, and time t7, which is the current time. Since the time difference T3 between time t3 and time t7 is equal to or greater than the time threshold Th, the alarm unit 5 does not issue a human approach alarm corresponding to the approach condition at time t7. The time threshold Th is a time that the driver of the vehicle 22 does not feel that there is a delay between the time when the alarm condition is satisfied and the time when the alarm is issued.

[0022] In this way, when it is the alarm unit 5's turn to issue an alarm, the alarm unit 5 will not issue an alarm if a time equal to or longer than the time threshold Th has elapsed since the safety information 20 on which the alarm is based was generated. Therefore, even when multiple alarm conditions are satisfied and the alarm device 1 issues alarms in order of the time at which it was determined that the alarm conditions were satisfied, it is possible to prevent a large discrepancy between the time at which the alarm conditions are satisfied and the time at which the alarm is actually issued.

[0023] On the other hand, if the alarm unit 5 determines that multiple alarm conditions are satisfied at the same time, it issues alarms corresponding to the multiple alarm conditions in order of decreasing priority according to a predetermined priority. For example, the alarm unit 5 has priority information 7 indicating the priority as shown in FIG. 1. The priority information 7 is information indicating the priority of multiple alarms. In FIG. 6, the alarm conditions are numbered from top to bottom in order of decreasing priority. Specifically, in FIG. 6, "No. 1" is the sudden acceleration / deceleration alarm, and "No. 2" is the human approach alarm. Therefore, in FIG. 6, the sudden acceleration / deceleration alarm has a higher priority than the human approach alarm. Therefore, if the alarm unit 5 determines that the acceleration / deceleration condition and the approach condition are satisfied at the same time, it first issues the sudden acceleration / deceleration alarm, and then issues the approach alarm after the sudden acceleration / deceleration alarm has been issued.

[0024] The reason why the sudden acceleration / deceleration warning has a higher priority than the human proximity warning is as follows. Whether the proximity condition, which is the warning condition for the human proximity warning, is met is determined by calculating the distance between the worker 31 and the vehicle 22 from the signal strength of the beacon 11 received by the acquisition unit 3, and determining whether the calculated distance is within the distance threshold. In other words, the distance between the worker 31 and the vehicle 22 is calculated "indirectly" from the signal strength. On the other hand, whether the acceleration / deceleration condition, which is the warning condition for the sudden acceleration / deceleration warning, is met is calculated "directly" from the acquired value of the acceleration sensor 9. Therefore, whether the acceleration / deceleration condition is met can be determined more clearly than whether the proximity condition is met. Therefore, by prioritizing the warning that can clearly determine whether the condition is met, safety can be further improved. By prioritizing the warnings in this way, even if multiple warning conditions are determined to be met at the same time, the warnings can be issued in an order that maximizes safety.

[0025] Furthermore, if an alarm condition corresponding to an alarm with a higher priority than a certain alarm is met while the alarm is sounding, the alarm unit 5 does not need to stop the currently sounding alarm and sound the alarm with the higher priority. In this case, the alarm unit 5 sounds the alarm with the higher priority after the currently sounding alarm has stopped sounding. Therefore, the priority here refers to the order that determines which corresponding alarm should be sounded first when multiple alarm conditions are met at the same time. Note that even when sounding a higher priority alarm after the currently sounding alarm has stopped sounding, if the time difference ΔT between the first time and the current time is equal to or greater than the time threshold Th, the alarm with the higher priority does not need to be sounded.

[0026] 1 supplies power to drive the acquisition unit 3 and the alarm unit 5, and supplies power supplied from a power source external to the alarm device 1, such as the power source of the vehicle 22, to the acquisition unit 3 and the alarm unit 5. The alarm device 1 may be realized by storing a program that realizes the acquisition unit 3, the alarm unit 5, and the power supply unit 12 in a memory unit of a general-purpose computer and having the program executed by the central processing unit of the general-purpose computer. Alternatively, the alarm device 1 may be a dedicated machine equipped with circuits and devices that realize the acquisition unit 3, the alarm unit 5, and the power supply unit 12. This concludes the description of the outline of the configuration of the alarm device 1.

[0027] Next, an alarm sounding method using the alarm device 1 will be described. First, an overview of the alarm sounding method will be described. In the alarm sounding method of this embodiment, first, the acquisition unit 3 acquires safety information 20 (acquisition step). Next, based on the safety information 20, it is determined whether a plurality of predetermined alarm conditions are met, and if it is determined that they are met, the alarm unit 5 issues an alarm in order of the earliest time that the alarm conditions were determined to be met (alarm step). Also, in the alarm step, when it is the alarm unit 5's turn to issue an alarm corresponding to one of the alarm conditions, it acquires the current time. Furthermore, if the time difference ΔT between the time (first time) when the safety information 20, which is the basis for determining that one of the alarm conditions is met, was generated or transmitted / received and the current time, is equal to or greater than a predetermined time threshold Th, the alarm unit 5 does not issue an alarm corresponding to one of the alarm conditions.

[0028] In this way, in the alarm sounding method using the alarm device 1, when it is the turn to issue an alarm, if a time equal to or greater than the predetermined time threshold Tth has passed since the safety information 20 on which the alarm is based was generated, no alarm is issued. Therefore, when multiple alarm conditions are satisfied, even if the alarms are issued in order of the earliest time at which the alarm conditions were determined to be satisfied, it is possible to prevent a large discrepancy between the time at which the alarm conditions are satisfied and the time at which the alarm is actually issued.

[0029] Next, a method for sounding an alarm using the alarm device 1 will be described in more detail with reference to Figs. 7 and 8. Fig. 7 is a flowchart showing an outline of the steps of the method for sounding an alarm using the alarm device 1 according to an embodiment of the present invention. Fig. 8 is a flowchart for sounding a human approach alarm in Fig. 7. Here, an outline of the method for sounding an alarm will first be described with reference to Fig. 7. First, the acquisition unit 3 of the alarm device 1 acquires the safety information 20 (S1 in Fig. 7, acquisition step). Next, the alarm unit 5 of the alarm device 1 determines whether the alarm conditions are met based on the safety information 20, and if it is determined that the alarm conditions are met, the process proceeds to S3, and if it is determined that the alarm conditions are not met, the process returns (S2 in Fig. 7). If it is determined that the alarm conditions are met in S2, the alarm unit 5 determines whether only one alarm condition is met, and if it is determined that only one alarm condition is met, the process proceeds to S4, and if it is determined that not only one alarm condition is met, the process proceeds to S5 (S3 in Fig. 7). Note that a case in which not only one alarm condition is met in S3 refers to a case in which both the approach condition and the acceleration / deceleration condition are met. If it is determined in S3 that only one alarm condition is satisfied, the alarm unit 5 performs sounding processing for an alarm corresponding to the satisfied alarm condition and then returns (S4 in FIG. 7). The sounding processing is a process of issuing an alarm if a predetermined time threshold Tth or more has not elapsed since the safety information 20 serving as the basis for the alarm was generated or transmitted, and not issuing an alarm if the predetermined time threshold Tth has elapsed. If more than one alarm condition is satisfied in S3, the alarm unit 5 performs sounding processing for an alarm that was determined to have satisfied the alarm condition earlier than the time threshold Tth (S5 in FIG. 7). For example, if the time threshold for the sudden acceleration / deceleration alarm was determined to have satisfied the alarm condition earlier than the time threshold for the human approach alarm, the alarm unit 5 sounds the sudden acceleration / deceleration alarm in S5. Next, the alarm unit 5 performs sounding processing for an alarm that was determined to have satisfied the alarm condition later than the time threshold for the human approach alarm, and then returns (S6 in FIG. 7). For example, if the time threshold for the sudden acceleration / deceleration alarm was determined to have satisfied the alarm condition earlier than the time threshold for the human approach alarm, the alarm unit 5 sounds the human approach alarm in S6. S4, S5, and S6 are also referred to as alarm processes.

[0030] Next, referring to Fig. 7, the sounding process when sounding a human approach alarm, specifically, the details of S6 in Fig. 7, will be described with reference to Fig. 8. First, the acquisition unit 3 determines whether it is receiving radio waves from the beacon 11, specifically, whether it has received at least one piece of distance information 23. If it is received, the process proceeds to S12, and if it is not received, the process proceeds to S13 (S11 in Fig. 8). If the distance information 23 is not received in S11, this means that a crew member is not on board the vehicle 22. Therefore, the acquisition unit 3 determines that there is no crew member information and returns to S11 (S13 in Fig. 8). If the distance information 23 is received in S11, the acquisition unit 3 recognizes the beacon 11 that is closest to the vehicle 22 among the beacons 11 indicated by the received distance information 23 as the beacon 11 carried by the crew member of the vehicle 22, and proceeds to S14 (S12 in Fig. 8). Next, the acquisition unit 3 determines whether it is receiving radio waves from a beacon 11 carried by a worker 31 other than the crew member, based on the distance between the beacon 11 and the vehicle 22 indicated in the received distance information 23. As a result, if it is determined that radio waves are being received, the process proceeds to S15, and if it is determined that radio waves are not being received, this step is repeated (S14 in FIG. 8). If it is determined in S14 that radio waves from a beacon 11 carried by a worker 31 other than the crew member are being received, the acquisition unit 3 measures the distance between the beacon 11 and the vehicle 22 using the measurement unit 10b and transmits the measurement result to the alarm unit 5 (S15 in FIG. 8). Next, the alarm unit 5 determines whether the distance between the beacon 11 and the vehicle 22 received from the acquisition unit 3 is within a distance threshold, and if it is within the distance threshold, the process proceeds to S17, and if it is not within the distance threshold, the process returns to S15 (S16 in FIG. 8). If it is determined in S16 that the distance between the beacon 11 and the vehicle 22 received from the acquisition unit 3 is within the distance threshold, the alarm unit 5 compares the time difference between the current time and the generation time of the received distance information 23 (S17 in FIG. 8) to determine whether it is less than the time threshold Th. As a result, if it is determined that it is less than the time threshold Th, the process proceeds to S19, and if it is determined that it is not less than the time threshold Th, the process proceeds to S20 (S18 in FIG. 8). If it is determined in S18 that the time difference is less than the time threshold Th, the alarm unit 5 issues an alarm and ends the flow of FIG. 8 (S19 in FIG. 8). If it is determined in S18 that the time difference is not less than the time threshold Th, the alarm unit 5 ends the flow of FIG. 8 without issuing an alarm (S20 in FIG. 8). The above is the details of sounding a human approach alarm in FIG. 7.

[0031] As described above, in the alarm device 1 and alarm sounding method of this embodiment, when the alarm conditions are satisfied and it is the alarm unit 5's turn to issue an alarm corresponding to the alarm conditions, the alarm unit 5 will not issue an alarm if a time equal to or greater than the time threshold Tth has elapsed since the safety information 20 on which the alarm is based was generated. Therefore, even when alarms are issued in order of the earliest time at which it was determined that the alarm conditions were satisfied, the difference between the time at which the alarm conditions were satisfied and the time at which the alarm is actually issued can be made shorter than before.

[0032] Furthermore, when multiple alarm conditions are determined to be satisfied at the same time, the alarm unit 5 of the alarm device 1 according to this embodiment issues alarms corresponding to the multiple alarm conditions in descending order of predetermined priority. By prioritizing the alarms in this way, even when multiple alarm conditions are determined to be satisfied at the same time, the alarms can be issued in an order that will further enhance safety.

[0033] Furthermore, the warning unit 5 of the warning device 1 according to this embodiment issues a warning corresponding to the sudden acceleration or deceleration first when the worker 31 approaches the vehicle 22 and the vehicle undergoes sudden acceleration or deceleration. Whether the worker 31 has approached is information that is indirectly acquired from the strength of the signal indicating the distance information 23 received from the beacon 11, whereas whether the vehicle has undergone sudden acceleration or deceleration is clear information that is directly acquired from the value acquired by the acceleration sensor 9. Therefore, with this configuration, safety can be further improved by prioritizing a warning based on clear information.

[0034] Although the present invention has been described above based on the embodiments, the present invention is not limited to the above embodiments, and modifications may be made without departing from the spirit of the present invention, and other techniques may be appropriately combined to the extent possible. Furthermore, publicly known or well-known techniques may be combined to the extent possible.

[0035] For example, in the above embodiment, two warning conditions, a person approach warning and a sudden acceleration / deceleration warning, are exemplified as warning conditions, but there may be three or more warning conditions. For example, a sudden turn warning indicating that the vehicle 22 has made a sudden turn may be added as a warning condition. The sudden turn warning has a higher priority than, for example, a person approach warning and a lower priority than a sudden acceleration / deceleration warning.

[0036] In the above-described embodiment, the first time is the time when the safety information 20 is generated, but the first time may be the time when the safety information 20 is transmitted or received. The time when the safety information 20 is transmitted may be assigned by the time assigning units 9b and 11b when the safety information 20 is transmitted. The time when the safety information 20 is received may be assigned by the acquiring unit 3 when the safety information 20 is received.

[0037] Furthermore, in the above embodiment, the distance between the beacon 11 and the vehicle 22 is calculated from the signal strength of the safety information 20 transmitted (sent) by the beacon 11, but the means for calculating the distance is not limited to calculating it from the signal strength. For example, the beacon 11 may transmit information including its own position information obtained from a GPS (Global Positioning System) satellite to the acquisition unit 3 as the safety information 20, and the acquisition unit 3 may then calculate the distance between the beacon 11 and the vehicle 22 from the position information upon receiving the safety information 20.

[0038] In the above embodiment, a forklift is used as an example of the vehicle 22, but the type of vehicle 22 is not particularly limited, and it may be a heavy machine, a truck, or a passenger car. [Explanation of symbols]

[0039] 1:Alarm device 3: Acquisition part 5: Alarm section 20:Safety information 21: Acceleration information (safety information) 21b: First time information (information indicating the first time) 22: Vehicle 23: Distance information (safety information) 23b: First time information (information indicating the first time) 31: Worker (pedestrian) Th: Time threshold ΔT: time difference

Claims

1. An alarm device mounted on a vehicle, comprising: an acquisition unit that acquires multiple types of safety information that is information related to the safety of the vehicle; and an alarm unit that determines whether multiple predetermined alarm conditions are met based on the safety information, and when it is determined that the safety information is met, issues alarms corresponding to the multiple alarm conditions in order starting from the alarm that was determined to satisfy the alarm condition earliest, the safety information includes information indicating a first time that is a time when the safety information is generated or transmitted / received, The alarm unit When it is the turn to issue the alarm corresponding to one of the plurality of alarm conditions, the current time is acquired, and when the time difference between the first time of the safety information, which is the basis for determining that one of the alarm conditions is satisfied, and the current time is equal to or greater than a predetermined time threshold, the alarm corresponding to one of the alarm conditions is not issued. An alarm device characterized by:

2. When the times at which it is determined that a plurality of the alarm conditions are satisfied are the same, the alarm unit issues alarms corresponding to the plurality of alarm conditions in a predetermined order of priority.

2. The alarm device according to claim 1 .

3. the safety information includes distance information indicating a distance between the vehicle and a pedestrian around the vehicle and acceleration information indicating an acceleration of the vehicle; The warning may include: a human proximity alarm that is issued when the distance between the pedestrian and the vehicle indicated by the distance information satisfies a proximity condition that is the alarm condition, that is, the distance between the pedestrian and the vehicle is within a predetermined distance threshold; a sudden acceleration / deceleration warning that is issued when an acceleration / deceleration condition, which is the warning condition, is satisfied, that is, the acceleration indicated by the acceleration information exceeds a predetermined acceleration threshold value; and and The sudden acceleration / deceleration warning has a higher priority than the human proximity warning.

3. The alarm device according to claim 2.

4. 1. A method for sounding an alarm for an alarm device mounted on a vehicle, comprising: an acquisition unit that performs an acquisition step of acquiring multiple types of safety information that are information related to the safety of the vehicle; and an alarm unit that performs an alarm step of determining whether multiple predetermined alarm conditions are met based on the safety information, and, if it is determined that the safety information is met, issuing alarms corresponding to the multiple alarm conditions in order from the alarm that was determined to satisfy the alarm condition earliest, the safety information includes information indicating a first time that is a time when the safety information is generated or transmitted / received, In the warning step, When it is the turn to issue the alarm corresponding to one of the plurality of alarm conditions, the current time is acquired, and when the time difference between the first time of the safety information, which is the basis for determining that one of the alarm conditions is satisfied, and the current time is equal to or greater than a predetermined time threshold, the alarm corresponding to one of the alarm conditions is not issued. An alarm sounding method comprising:

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