Worker Detection System

Abstract

To notify a worker or the like on an outer side of a refrigerated warehouse of a stop of a forklift when the forklift for performing a cargo handling work inside the refrigerated warehouse is emergently stopped due to a failure or the like.SOLUTION: A worker detection system includes: a refrigerated warehouse 4; a forklift 1 for performing a cargo handling work inside the refrigerated warehouse 4; an in-warehouse determination section 21 for determining whether the forklift 1 is positioned inside the refrigerated warehouse 4; a stop determination section 22 for determining whether the forklift 1 is stopped for a predetermined time; and a notification section 3 for issuing a notification that the forklift 1 is stopped inside the refrigerated warehouse 4 to an outer side of the refrigerated warehouse 4. The notification section 3 issues a notification when the forklift 1 is positioned inside the refrigerated warehouse 4 and also the forklift 1 is stopped for a predetermined time.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a worker detection system equipped with a forklift for handling cargo inside a refrigerated warehouse. [Background technology]

[0002] It is known that loading and unloading work is performed using a forklift inside a refrigerated warehouse where cargo is stored in a refrigerated or frozen state. When a forklift performs loading and unloading work inside a refrigerated warehouse for more than a certain period of time, the low temperature can cause the hydraulic hoses of the hydraulic equipment installed on the forklift to harden, the battery performance to deteriorate, and so on, which can lead to the forklift breaking down.

[0003] When a forklift used for loading and unloading operations in a refrigerated warehouse comes to an emergency stop due to a breakdown or other reason, there is a risk that the operator will leave the forklift behind and go outside the warehouse, resulting in the forklift not being found for a long time.

[0004] In addition, in an order-picking forklift (see Patent Document 1), in which the driving section rises and falls together with the forks, if the forklift makes an emergency stop due to a malfunction or other reason while the driving section is raised, the operator may not be able to get down to the ground and may be trapped inside the refrigerated warehouse together with the forklift that has stopped in an emergency for a long period of time.

[0005] Patent Document 2 discloses a technology that warns an operator to leave a refrigerator when a forklift performs loading and unloading work inside the refrigerator for a certain period of time or more. However, the operator may not notice the warning or may ignore the warning and continue the loading and unloading work, which may cause the forklift to break down and make an emergency stop. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] Patent Publication No. 2022-56041 [Patent Document 2] JP 2010-173760 A Summary of the Invention [Problem to be solved by the invention]

[0007] Therefore, the problem that the present invention aims to solve is to provide a worker detection system that can notify workers outside a refrigerated warehouse when a forklift performing loading and unloading operations inside the refrigerated warehouse makes an emergency stop due to a malfunction or the like. [Means for solving the problem]

[0008] In order to solve the above problems, the worker detection system according to the present invention is a worker detection system including a refrigerated warehouse and a forklift performing loading and unloading work inside the refrigerated warehouse. The worker detection system further includes an inside determination unit that determines whether the forklift is located inside the refrigerated warehouse, a stop determination unit that determines whether the forklift has been stopped for a predetermined time, and an alarm unit that notifies the outside of the refrigerated warehouse that the forklift has been stopped inside the refrigerated warehouse. The alarm unit is configured to notify the outside of the refrigerated warehouse when the forklift is located inside the refrigerated warehouse and has been stopped for the predetermined time.

[0009] The forklift is preferably configured so that the driving section in which the operator sits cannot be raised or lowered, and the stop determination section is preferably configured to determine whether either the traveling drive section, which drives the forklift in forward and backward travel directions, or the turning drive section, which drives the forklift in a turning direction, has stopped.

[0010] In addition, the forklift is preferably configured to raise and lower the driving section in which the operator sits together with the forks, and the stop determination section is preferably configured to determine whether any of the travel drive section that drives the forklift in forward and backward travel directions, the rotation drive section that drives the forklift in a rotation direction, or the lifting drive section that drives the driving section in a lifting and lowering direction has stopped.

[0011] Preferably, the interior determination unit is configured to determine that the forklift is located inside the refrigerated warehouse when an outside air temperature sensor provided on the forklift indicates that the outside air temperature is equal to or lower than a predetermined temperature.

[0012] The notification unit may change the notification operation depending on the stopping conditions of the forklift.

[0013] The notification unit may also include any one of an alarm unit, a lamp unit, a projector unit, and a monitor unit installed outside the refrigerated warehouse. Effect of the Invention

[0014] According to the present invention, when a forklift performing loading and unloading operations inside a refrigerated warehouse makes an emergency stop, workers outside the refrigerated warehouse can be notified of this, thereby preventing the forklift that has stopped in an emergency from being discovered inside the refrigerated warehouse for a long period of time and preventing the operator from being trapped together with the forklift that has stopped in an emergency. [Brief description of the drawings]

[0015] [Figure 1] 1 is a schematic diagram showing a worker detection system according to a first embodiment. [Diagram 2] FIG. 1 is a block diagram showing a worker detection system according to a first embodiment. [Diagram 3] FIG. 4 is a flowchart showing a control method of the notification unit. [Figure 4] FIG. 11 is a schematic diagram showing a worker detection system according to a second embodiment. [Diagram 5] FIG. 11 is a block diagram showing a worker detection system according to a second embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0016] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, an embodiment of a worker detection system according to the present invention will be described with reference to the drawings.

[0017] [First embodiment] A first embodiment of a worker detection system will be described.

[0018] 1, the worker detection system includes a forklift 1, a determination unit 2, a notification unit 3, and a refrigerated warehouse 4. The refrigerated warehouse 4 is configured to maintain the interior of the warehouse at a predetermined low temperature, and is configured to store cargo P in a refrigerated or frozen state on shelves L installed within the warehouse.

[0019] The forklift 1 is configured to handle and transport cargo P. The forklift 1 enters and exits the refrigerated warehouse 4 through an entrance / exit 40, and performs handling work inside and outside the refrigerated warehouse 4.

[0020] In this embodiment, the forklift 1 is a reach forklift. The forklift 1 includes a driving section 16 on which an operator O rides, and the driving section 16 is configured not to ascend or descend. The forklift 1 is configured such that the forks provided in front of the driving section 16 ascend or descend and move forward or backward.

[0021] The driving unit 16 is provided with a steering wheel and a number of operation levers that are operated by an operator O riding on the driving unit 16. When the operator O operates the steering wheel and the number of operation levers, the forklift 1 travels forward and backward and turns, and the forks provided on the forklift 1 are configured to rise and lower and move forward and backward.

[0022] 2, the forklift 1 includes a control unit 10, an outside air temperature sensor 11, a traveling drive unit 12, a turning drive unit 13, and a communication unit 15. The control unit 10 is connected to the outside air temperature sensor 11, the traveling drive unit 12, the turning drive unit 13, and the communication unit 15 via a communication line (bus), and is configured to control these.

[0023] The control unit 10 is composed of, for example, a CPU (Central Processing Unit), an input / output interface, a ROM, a RAM, etc., and stores programs for processing information.

[0024] The outside air temperature sensor 11 is configured to detect the outside air temperature, and is configured, for example, by an NTC thermistor.

[0025] The communication unit 15 is configured to transmit the outside air temperature detected by the outside air temperature sensor 11, etc. The communication unit 15 includes a wireless communication circuit, and performs a process of transmitting and receiving communication data. The wireless communication circuit is a circuit for performing wireless communication, and is connected to a communication antenna. The wireless communication circuit is configured to perform a process of transmitting and receiving communication data using wireless communication such as WiFi, based on a wireless communication method that complies with a known communication standard.

[0026] The traveling drive unit 12 is made up of an electric motor provided at the rear of the forklift 1, and is configured to drive the forklift 1 in the forward and backward directions by rotating the rear wheels in forward and reverse directions. The turning drive unit 13 is made up of an electric motor provided at the rear of the forklift 1, and is configured to drive the forklift 1 in the turning direction by rotating the rear wheels.

[0027] The communication unit 15 is configured to transmit output data indicating whether the traveling drive unit 12 and the turning drive unit 13 are stopped or not.

[0028] 2, the determination unit 2 includes a control unit 20, an interior determination unit 21, a stop determination unit 22, and a communication unit 23. The control unit 20 is connected to the interior determination unit 21, the stop determination unit 22, and the communication unit 23 via a communication line (bus), and is configured to control these. The communication unit 23 is configured to receive information transmitted from the communication unit 15 of the forklift 1. The interior determination unit 21 is configured to determine whether or not the forklift 1 is located inside the refrigerated warehouse 4.

[0029] The refrigerated warehouse 4 is set so that the temperature inside the warehouse is equal to or lower than a predetermined temperature lower than the temperature outside the warehouse in order to store the cargo P in a refrigerated or frozen state. Therefore, the interior determination unit 21 is configured to determine that the forklift 1 is located inside the refrigerated warehouse 4 when the outside air temperature detected by the outside air temperature sensor 11 is equal to or lower than the predetermined temperature.

[0030] Further, the stop determination unit 22 is configured to determine whether the forklift 1 is stopped. The stop determination unit 22 is configured to determine whether either the traveling drive unit 12 or the slewing drive unit 13 has been stopped for a predetermined time based on communication data transmitted from the communication unit 15 of the forklift 1. If either the traveling drive unit 12 or the slewing drive unit 13 has been stopped for a predetermined time, the forklift 1 has been brought to an emergency stop due to a malfunction or the like, and therefore cannot stop inside the refrigerated warehouse 4 and cannot go outside.

[0031] 2, the notification unit 3 includes a control unit 30, an alarm unit 31, and a communication unit 32. The alarm unit 31 is configured to notify the outside of the refrigerated warehouse 4 that the forklift 1 is stopped inside the refrigerated warehouse 4. The communication unit 32 is configured to receive communication data transmitted from the communication unit 22 of the determination unit 2.

[0032] The control unit 30 is connected to the alarm unit 31 and the communication unit 32 via a communication line (bus) and is configured to control them. Based on the determination result of the determination unit 2, the control unit 30 controls the alarm unit 31 to be activated when the forklift 1 is located inside the refrigerated warehouse 4 and the forklift 1 (either the traveling drive unit 12 or the slewing drive unit 13) has been stopped for a predetermined time.

[0033] A control method of the notification unit 3 by the control unit 30 will be described with reference to FIG. The interior determination unit 21 determines whether or not the forklift 1 is located inside the refrigerated warehouse 4 (Step S1). Then, when the interior determination unit 21 determines that the forklift 1 is located inside the refrigerated warehouse 4, the stop determination unit 22 determines whether or not either the traveling drive unit 12 or the slewing drive unit 13 of the forklift 1 has been stopped for a predetermined time (Step S2).

[0034] Then, when the forklift 1 is located inside the refrigerated warehouse 4 and either the traveling drive unit 12 or the slewing drive unit 13 of the forklift 1 has been stopped for a predetermined time, the interior determination unit 21 and the stop determination unit 22 activate the alarm unit 31 to emit an alarm sound outside the refrigerated warehouse 4, thereby notifying the user that the forklift 1 has been made an emergency stop inside the refrigerated warehouse 4 (step S3).

[0035] When the interior judgment unit 21 does not judge that the forklift 1 is located inside the refrigerated warehouse 4 (step S1), or when the stop judgment unit 22 judges that either the traveling drive unit 12 or the slewing drive unit 13 of the forklift 1 has not been stopped for a predetermined time (step S2), the judgment operations of the interior judgment unit 21 and the stop judgment unit 22 are repeated so that the alarm unit 31 is not activated.

[0036] With the worker detection system of the above embodiment, when either the traveling drive unit 12 or the slewing drive unit 13 of the forklift 1 is brought to an emergency stop inside the refrigerated warehouse 4 due to a malfunction or the like, the notification unit 3 can notify the operator that the forklift 1 has been brought to an emergency stop inside the refrigerated warehouse 4. Therefore, even if the operator O goes outside the refrigerated warehouse 4 leaving the forklift 1 that has been brought to an emergency stop behind, the forklift 1 that has been brought to an emergency stop will not go undiscovered for a long period of time.

[0037] [Second embodiment] A second embodiment of the worker detection system will be described below. Note that, in order to avoid duplication, descriptions of the same configuration as in the first embodiment may be omitted.

[0038] 4, the worker detection system includes a forklift 1, a determination unit 2, a notification unit 3, and a refrigerated warehouse 4. The refrigerated warehouse 4 is configured to maintain the interior of the warehouse at a predetermined low temperature, and is configured to store cargo P in a refrigerated or frozen state on shelves L installed within the warehouse.

[0039] The forklift 1 is configured to handle and transport cargo P. The forklift 1 enters and exits the refrigerated warehouse 4 through an entrance / exit 40, and performs handling work inside and outside the refrigerated warehouse 4.

[0040] In this embodiment, the forklift 1 is configured as an order-picking forklift. The forklift 1 includes a driving section 16 on which an operator O rides, and the driving section 16 is configured to rise and fall together with the forks. The forklift 1 raises the driving section 16 together with the forks, scoops up a pallet with the forks, and the operator O riding on the driving section 16 can load and unload packages P on the pallet.

[0041] The driving unit 16 is provided with a steering wheel and a plurality of operation levers that are operated by an operator O riding on the driving unit 16. When the operator O operates the steering wheel and the plurality of operation levers, the forklift 1 travels forward and backward and turns, and the driving unit 16 moves up and down together with the forks.

[0042] 5, the forklift 1 includes a control unit 10, an outside air temperature sensor 11, a travel drive unit 12, a swivel drive unit 13, a lift drive unit 14, and a communication unit 15. The control unit 10 is connected to the outside air temperature sensor 11, the travel drive unit 12, the swivel drive unit 13, the lift drive unit 14, and the communication unit 15 via a communication line (bus), and is configured to control these.

[0043] The outside air temperature sensor 11 is configured to detect the outside air temperature. The communication unit 15 is configured to transmit the outside air temperature detected by the outside air temperature sensor 10 and the like.

[0044] The traveling drive unit 12 is configured to drive the forklift 1 in the forward and backward directions. The slewing drive unit 13 is configured to drive the forklift 1 in the slewing direction. The lifting drive unit 14 includes a pump and an electric motor that supply and discharge hydraulic oil to a lift cylinder provided on the lifting mast, and is configured to lift and lower the fork and driving unit 16 along the lifting mast by driving the pump and the electric motor.

[0045] The communication unit 15 is configured to transmit output data indicating whether the traveling drive unit 12, the turning drive unit 13, and the lifting drive unit 14 are stopped or not.

[0046] 5, the determination unit 2 includes a control unit 20, an interior determination unit 21, a stop determination unit 22, and a communication unit 23. The control unit 20 is connected to the interior determination unit 21, the stop determination unit 22, and the communication unit 23 via a communication line (bus), and is configured to control these. The communication unit 23 is configured to receive information transmitted from the communication unit 15 of the forklift 1. The interior determination unit 21 is configured to determine whether or not the forklift 1 is located inside the refrigerated warehouse 4.

[0047] The stoppage determination unit 22 is configured to determine whether the forklift 1 is stopped or not. The stoppage determination unit 22 is configured to determine whether any of the traveling drive unit 12, the slewing drive unit 13, and the lifting drive unit 14 has been stopped for a predetermined time based on communication data transmitted from the communication unit 15 of the forklift 1.

[0048] If either the traveling drive unit 12 or the slewing drive unit 13 has stopped for a predetermined time, the forklift 1 has been brought to an emergency stop due to a malfunction or the like, and is therefore unable to stop inside the refrigerated warehouse 4 and move out of the warehouse. Also, if the lift drive unit 14 has been stopped for a predetermined time while the driver's unit 16 on which the operator O sits is located at a high position, the forklift 1 has been brought to an emergency stop due to a malfunction or the like, and the operator O is unable to get down to the floor surface, and is also unable to move the forklift 1 out of the refrigerated warehouse 4.

[0049] 5, the notification unit 3 includes a control unit 30, an alarm unit 31, and a communication unit 32. The alarm unit 31 is configured to notify the outside of the refrigerated warehouse 4 that the forklift 1 is stopped inside the refrigerated warehouse 4. The communication unit 32 is configured to receive communication data transmitted from the communication unit 22 of the determination unit 2.

[0050] The control unit 30 is connected to the alarm unit 31 and the communication unit 32 via a communication line (bus) and is configured to control them. Based on the determination result of the determination unit 2, the control unit 30 controls the alarm unit 31 to be activated when the forklift 1 is located inside the refrigerated warehouse 4 and the forklift 1 (any of the traveling drive unit 12, the slewing drive unit 13, and the lifting drive unit 14) has been stopped for a predetermined time.

[0051] The control method of the notification unit 3 by the control unit 30 is the same as that in the first embodiment. 3, the interior determination unit 21 determines whether or not the forklift 1 is located inside the refrigerated warehouse 4 (step S1). Then, when the interior determination unit 21 determines that the forklift 1 is located inside the refrigerated warehouse 4, the stop determination unit 22 determines whether or not any of the traveling drive unit 12, the swivel drive unit 13, and the lifting drive unit 14 of the forklift 1 has been stopped for a predetermined time (step S2).

[0052] Then, when the interior judgment unit 21 and the stop judgment unit 22 determine that the forklift 1 is located inside the refrigerated warehouse 4 and any one of the travel drive unit 12, the swivel drive unit 13 and the lift drive unit 14 of the forklift 1 has been stopped for a predetermined time, an alarm sound is emitted outside the refrigerated warehouse 4 by actuating the alarm unit 31 to notify that the forklift 1 has come to an emergency stop inside the refrigerated warehouse 4 (step S3).

[0053] When the interior judgment unit 21 does not judge that the forklift 1 is located inside the refrigerated warehouse 4 (step S1), or when the stop judgment unit 22 judges that any of the travel drive unit 12, the swivel drive unit 13 and the lift drive unit 14 of the forklift 1 has not been stopped for a predetermined period of time (step S2), the judgment operations of the interior judgment unit 21 and the stop judgment unit 22 are repeated so that the alarm unit 31 is not activated.

[0054] With the worker detection system of the above embodiment, when any of the travel drive unit 12, the swivel drive unit 13, and the lift drive unit 14 of the forklift 1 is brought to an emergency stop inside the refrigerated warehouse 4 due to a malfunction or the like, the notification unit 3 can notify the operator that the forklift 1 has been brought to an emergency stop inside the refrigerated warehouse 4. Therefore, even if the operator O goes outside the refrigerated warehouse 4 leaving the forklift 1 that has been brought to an emergency stop behind, the forklift 1 that has been brought to an emergency stop will not go undiscovered for a long period of time.

[0055] Although the preferred embodiments of the present invention have been described above, the configuration of the present invention is not limited to these embodiments. For example, the following modifications are possible.

[0056] The means for determining whether or not the forklift 1 is located inside the refrigerated warehouse 4 is not limited to the above configuration. For example, the forklift 1 may be provided with a position sensor, and the interior determination unit 21 may store map information of the refrigerated warehouse 4, and the interior determination unit 21 may be configured to determine whether or not the forklift 1 is located inside the refrigerated warehouse 4 based on the coordinate position transmitted from the position sensor of the forklift 1.

[0057] The control unit 30 of the notification unit 3 may change the notification operation depending on the stopping conditions of the forklift 1. For example, the sound emitted from the alarm unit 31 may be increased in volume or changed as the stopping time of the forklift 1 increases. The sound emitted from the alarm unit 31 may be increased in volume or changed depending on which of the traveling drive unit 12, the slewing drive unit 13, and the lifting drive unit 14 of the forklift 1 has stopped.

[0058] In the above embodiment, the notification unit 3 is equipped with the alarm unit 31, but it may also be equipped with, for example, a lamp unit that emits light in a conspicuous color to notify those in the vicinity at the entrance or exit of the refrigerated warehouse 4, or a projector unit or monitor unit that projects letters, images, figures, etc. onto a wall to notify those in the vicinity that the forklift 1 has stopped.

[0059] As described above, the worker detection system according to the present invention includes the refrigerated warehouse 4, the forklift 1 performing loading and unloading work within the refrigerated warehouse 4, the interior determination unit 21 determining whether the forklift 1 is located within the refrigerated warehouse 4, the stop determination unit 22 determining whether the forklift 1 has been stopped for a predetermined time, and the notification unit 3 that notifies the outside of the refrigerated warehouse 4 that the forklift 1 has been stopped within the refrigerated warehouse 4. The notification unit 3 is configured to issue a notification when the forklift 1 is located within the refrigerated warehouse 4 and has been stopped for the predetermined time.

[0060] Therefore, when the forklift 1 is brought to an emergency stop inside the refrigerated warehouse 4 due to a breakdown or the like, the notification unit 3 can notify the operator that the forklift 1 has been brought to an emergency stop inside the refrigerated warehouse 4. Therefore, even if the operator O goes outside the refrigerated warehouse 4 leaving the forklift 1 that has been brought to an emergency stop behind, the forklift 1 that has been brought to an emergency stop will not go undiscovered for a long period of time. [Explanation of symbols]

[0061] 1. Forklift 2 Judgment section 3. Notification Department 4. Refrigerated Warehouse 16 Driving Department 12 Travel drive unit 13 Swivel drive unit 14 Lifting drive unit 21 Warehouse Judgment Unit 22 Stop judgment section O Operator

Claims

1. A worker detection system including a refrigerated warehouse and a forklift that performs loading and unloading work inside the refrigerated warehouse, an interior determination unit that determines whether the forklift is located inside the refrigerated warehouse; a stop determination unit that determines whether the forklift has been stopped for a predetermined period of time; An alarm unit that notifies the outside of the refrigerated warehouse that the forklift is stopped inside the refrigerated warehouse, The notification unit is configured to notify the outside of the refrigerated warehouse when the forklift is located inside the refrigerated warehouse and the forklift has been stopped for a predetermined time. A worker detection system comprising:

2. The forklift is configured not to raise or lower the driving section on which the operator sits, The stop determination unit is configured to determine whether or not either a traveling drive unit that drives the forklift in forward and backward travel directions or a turning drive unit that drives the forklift in a turning direction has stopped.

2. The worker detection system according to claim 1 .

3. The forklift is configured to raise and lower a driving section on which an operator sits together with the forks, The stop determination unit is configured to determine whether any of a traveling drive unit that drives the forklift in forward and backward travel directions, a rotation drive unit that drives the forklift in a rotation direction, and a lift drive unit that drives the driving unit in a lift direction is stopped.

2. The worker detection system according to claim 1,

4. The interior determination unit is configured to determine that the forklift is located inside the refrigerated warehouse when the exterior air temperature is equal to or lower than a predetermined temperature using an exterior air temperature sensor provided on the forklift.

2. The worker detection system according to claim 1 .

5. The notification unit changes the notification operation depending on a stopping condition of the forklift.

2. The worker detection system according to claim 1,

6. The notification unit includes any one of an alarm unit, a lamp unit, a projector unit, and a monitor unit installed outside the refrigerated warehouse.

6. The worker detection system according to claim 1,

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