forklift

Abstract

To provide a forklift capable of carrying cargo without damaging the same.SOLUTION: A forklift includes an operation control unit 114 that controls reach operation of a mast and controls up-and-down operation of a fork along the mast based on an operator's operation accepted by an operation unit 34. The operation control unit 114 executes at least one of a first control to stop reach-in operation of the mast when the detection result of a loading sensor 40 indicates that the fork is loaded with a cargo and the reach amount detected by a reach amount sensor 44 is a first threshold value or less, and a second control to stop the lowering operation of the fork when the detection result of the loading sensor 40 indicates that the fork is loaded with a cargo and the height detected by a lifting height sensor 42 is a second threshold value or less.SELECTED DRAWING: Figure 3

Description

[Technical field]

[0001] The present invention relates to a forklift. [Background technology]

[0002] 2. Description of the Related Art Conventionally, there is known a technique for transporting cargo using a forklift without damaging the cargo (see, for example, Patent Document 1). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2006-206243 A Summary of the Invention [Problem to be solved by the invention]

[0004] Here, when a driver operates a reach forklift, in a reach-out state, the driver may mistakenly lower the forks downward and reach in the mast, causing the load to hit the reach leg. Also, when a driver operates a reach forklift, in a reach-in state, the driver may mistakenly lower the forks downward, causing the load to hit the reach leg. Therefore, when a driver operates a reach forklift, it may be difficult for the driver to transport the load without hitting the reach leg. [Means for solving the problem]

[0005] A forklift that achieves the above-mentioned object is provided with a mast that moves back and forth along a pair of left and right reach legs located forward of a vehicle body, and a pair of left and right forks are provided in front of the mast, and is equipped with a load sensor that detects whether or not a load is loaded on the forks, an operation unit that receives operations of the forklift by a driver, a reach amount sensor that detects the reach amount of the mast, a height sensor that detects the height of the forks, and an operation control unit that controls the reach operation of the mast and the up and down movement of the forks along the mast based on the operation of the driver received by the operation unit, wherein the operation control unit executes at least one of a first control that stops a reach-in operation of the mast when the detection result of the load sensor indicates that the forks are loaded with a load and the reach amount detected by the reach amount sensor is equal to or less than a first threshold, and a second control that stops a lowering operation of the forks when the detection result of the load sensor indicates that the forks are loaded with a load and the height detected by the height sensor is equal to or less than a second threshold.

[0006] According to this configuration, even if the driver makes an incorrect operation, the operation control unit stops the operation of the mast and the forks so that the load does not hit the reach leg, allowing the forklift to transport the load without causing damage.

[0007] In the forklift, the first threshold value and the second threshold value are values ​​based on a size of the own device, and the larger the size of the own device, the larger the value is. Generally, the larger the forklift is, the larger the load it can transport. With this configuration, the operation control unit executes the first control and the second control based on the first threshold and the second threshold, which are larger as the size of the forklift increases. This allows the forklift 10 to transport a load that is large according to its own size without damaging the load.

[0008] In the forklift, the first threshold value and the second threshold value are values ​​based on a shape of the luggage. According to this configuration, the operation control unit stops the operation of the mast and forks based on the first threshold and the second threshold according to the shape of the luggage, allowing the luggage to be transported without causing damage.

[0009] The forklift further includes an input unit that receives input from the occupant specifying the first threshold value and the second threshold value, and a determination unit that determines the first threshold value and the second threshold value based on the input to the input unit, and the operation control unit executes at least one of the first control and the second control based on the first threshold value and the second threshold value determined by the determination unit.

[0010] According to this configuration, the operation control unit stops the operation of the mast and the forks based on the first threshold and the second threshold desired by the occupant, making it possible to transport luggage without causing damage to the luggage.

[0011] In the forklift truck, the reach amount sensor and the lift height sensor are wire type sensors. Effect of the Invention

[0012] According to the present invention, a reach forklift can transport a load without hitting the reach leg. [Brief description of the drawings]

[0013] [Figure 1] Side view of a forklift. [Diagram 2] FIG. [Diagram 3] FIG. 2 is a diagram showing the configuration of a control device. [Figure 4] FIG. 13 is a diagram used to explain a scene in which a reach action is stopped. [Diagram 5]A diagram used to explain the scene when the up and down movement of the forks is stopped. [Figure 6] 4 is a flowchart showing an example of control by the control device. [Figure 7] FIG. [Figure 8] FIG. 4 is a diagram showing an example of a display image. [Figure 9] FIG. 2 is a diagram showing the configuration of a control device. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0014] <Embodiment> DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, an embodiment of a forklift according to the present invention will be described with reference to the drawings. [Forklift 10 configuration] As shown in FIG. 1 and FIG. 2, the forklift 10 includes, for example, a vehicle body 11, a reach leg 12, front wheels 13, rear wheels 14, a loading device 21, an operation unit 34, a load sensor 40, a lifting height sensor 42, and a reach amount sensor 44. The forklift 10 also includes, for example, a hydraulic mechanism 52 and a control device 100. The forklift 10 may be operated manually by an operator riding on the forklift 10, or may be switched between automatic and manual operation. In other words, the forklift 10 may be operated manually by an operator. In the following description, the terms front, rear, left, right, top, bottom, and bottom refer to the front, rear, left, right, top, and bottom with respect to the forklift 10. The front and rear direction may also be referred to as the traveling direction of the forklift 10. The left and right direction may also be referred to as the vehicle width direction of the forklift 10. The up and down direction may also be referred to as the height direction of the forklift 10.

[0015] The reach legs 12 are disposed forward of the vehicle body 11. Two reach legs 12 are provided spaced apart from each other in the left-right direction. The pair of left and right reach legs 12 extend forward from the vehicle body 11. One front wheel 13 is provided on each reach leg 12. The rear wheels 14 are provided on the vehicle body 11. The rear wheels 14 are, for example, steered wheels and drive wheels.

[0016] The loading device 21 is provided forward of the vehicle body 11. The loading device 21 includes a mast 22, a lift bracket 25, a fork 26, a lift cylinder 31, a tilt cylinder 32, and a reach cylinder 33.

[0017] The mast 22 is a multi-stage mast. The mast 22 includes an outer mast 23 and an inner mast 24. The inner mast 24 is provided so as to be movable up and down relative to the outer mast 23.

[0018] The lift bracket 25 is fixed to the inner mast 24. The forks 26 are fixed to the lift bracket 25. Two forks 26 are provided spaced apart from each other in the left-right direction. The lift bracket 25 is a member for fixing the pair of left and right forks 26 to the inner mast 24.

[0019] The lift cylinder 31 is a hydraulic cylinder. The lift bracket 25 moves up and down by supplying and discharging hydraulic oil to the lift cylinder 31. The forks 26 move up and down together with the lift bracket 25.

[0020] The tilt cylinder 32 is a hydraulic cylinder. The lift bracket 25 tilts in the front-rear direction by supplying and discharging hydraulic oil to the tilt cylinder 32. The tilting includes forward tilting, which tilts the lift bracket 25 forward, and rearward tilting, which tilts the lift bracket 25 rearward. The fork 26 tilts together with the lift bracket 25.

[0021] The reach cylinder 33 is a hydraulic cylinder. The mast 22 moves in the front-rear direction by supplying and discharging hydraulic oil to the reach cylinder 33. The forks 26 move in the front-rear direction together with the mast 22. Hereinafter, moving the forks 26 forward by the reach cylinder 33 will be referred to as a reach-out operation, and moving the forks 26 backward by the reach cylinder 33 will be referred to as a reach-in operation.

[0022] The operation unit 34 accepts operations by an occupant of the forklift 10. The operation unit 34 includes a lift operation unit 35, a tilt operation unit 36, and a reach operation unit 37. The lift operation unit 35 is operated by the occupant of the forklift 10. In this embodiment, the lift operation unit 35 is a lever. The lift operation unit 35 tilts forward or backward from a neutral position. The lift operation unit 35 is operated by the occupant of the forklift 10 when raising or lowering the forks 26.

[0023] The tilt operation unit 36 ​​is operated by the driver of the forklift 10. In this embodiment, the tilt operation unit 36 ​​is a lever. The tilt operation unit 36 ​​tilts forward or backward from a neutral position. The tilt operation unit 36 ​​is operated by the driver of the forklift 10 when tilting the forks 26.

[0024] The reach operation unit 37 is operated by the driver of the forklift 10. In this embodiment, the reach operation unit 37 is a lever. The reach operation unit 37 tilts forward or backward from a neutral position. The reach operation unit 37 is operated by the driver of the forklift 10 when moving the forks 26 in the forward or backward direction.

[0025] The loading sensor 40 detects whether or not a load is loaded on the forks 26. The loading sensor 40 is realized, for example, by a lever-type sensor that is pressed when a load is loaded on the forks 26. The loading sensor 40 supplies information indicating that a load is loaded on the forks 26 to the control device 100.

[0026] The height sensor 42 detects the height of the forks 26 raised and lowered by the lift cylinder 31. The height of the forks 26 is, for example, the height from the ground surface of the forklift 10 to the surface on which the forks 26 carry a load. The height sensor 42 is realized by, for example, a wire-type sensor. In detail, the height sensor 42 detects the height of the forks 26 based on the amount of wire that is pulled out in response to the lifting operation of the forks 26 and wound up in response to the lowering operation of the forks 26. The height of the forks 26 is, for example, smallest when the forks 26 are moved to the lowest position and largest when the forks 26 are moved to the highest position. The height sensor 42 supplies information indicating the detected height of the forks 26 to the control device 100.

[0027] The reach amount sensor 44 detects the amount of movement of the mast 22 by the reach cylinder 33. In the following description, the amount of movement of the mast 22 is referred to as the reach amount. The reach amount sensor 44 is realized by, for example, a wire-type sensor. In detail, the reach amount sensor 44 detects the reach amount based on the amount of wire that is pulled out in response to the reach-out operation of the mast 22 and wound up in response to the reach-in operation of the mast 22. For example, the reach amount takes a smallest value when the mast 22 is moved to a position closest to the vehicle body 11, and takes a large value when the mast 22 is moved to an end of the reach leg 12 opposite to the end on the vehicle body 11 side. The reach amount sensor 44 supplies information indicating the detected reach amount to the control device 100.

[0028] The hydraulic mechanism 52 is a member for controlling the supply and discharge of hydraulic oil to the hydraulic equipment. The hydraulic equipment includes the lift cylinder 31, the tilt cylinder 32, and the reach cylinder 33. The hydraulic mechanism 52 includes a pump that discharges the hydraulic oil, and a control valve that controls the supply and discharge of the hydraulic oil to the hydraulic equipment.

[0029] The control device 100 controls each unit included in the forklift 10. The control device 100 will be described in detail below. [Control device configuration] 3, the control device 100 is connected to the operation unit 34, the load sensor 40, the lifting height sensor 42, and the reach amount sensor 44, and the control device 100 acquires various information from each unit. In addition, the control device 100 is connected to a hydraulic mechanism 52, and the control device 100 controls each unit.

[0030] The control device 100 includes, for example, a control unit 110 and a storage unit 200. The control unit 110 is realized by, for example, a hardware processor such as a CPU (Central Processing Unit) executing a program (software). Some or all of these components may be realized by hardware (including circuitry) such as an LSI (Large Scale Integration), an ASIC (Application Specific Integrated Circuit), an FPGA (Field-Programmable Gate Array), or a GPU (Graphics Processing Unit), or may be realized by a combination of software and hardware. The program is stored in the storage unit 200 in advance.

[0031] The storage unit 200 is realized by a storage device (a storage device having a non-transitory storage medium) such as an HDD (Hard Disk Drive) or a flash memory, or a removable storage medium such as a DVD or a CD-ROM. For example, the storage unit 200 stores first threshold information 202 indicating a first threshold and second threshold information 204 indicating a second threshold. Details of the first threshold information 202 and the second threshold information 204 will be described later.

[0032] The control unit 110 includes, for example, an acquisition unit 112 and an operation control unit 114. The acquisition unit 112 acquires, for example, information indicating the amount of operation input to the operation unit 34 from the operation unit 34. The acquisition unit 112 acquires information indicating that luggage PG is loaded on the forks 26 from the loading sensor 40. The acquisition unit 112 acquires information indicating the height of the forks 26 from the lifting height sensor 42. The acquisition unit 112 acquires information indicating the reach amount from the reach amount sensor 44.

[0033] The operation control unit 114 controls the reach operation of the mast 22 based on the operation of the driver of the forklift 10 received by the operation unit 34, and controls the up and down movement of the forks 26 along the mast 22.

[0034] [Stop Reaching] As shown in Fig. 4, when the fork 26 is loaded with luggage PG and the height of the fork 26 is lower than the height of the reach leg 12, moving the mast 22 toward the vehicle body 11 may cause the luggage PG to hit the front surface SF1 of the reach leg 12. In this case, it is preferable that the reach-in operation of the mast 22 is stopped so that the reach amount does not become smaller than a first threshold value Th1. The first threshold value Th1 is, for example, a value indicating the length of the reach leg 12 in the front-rear direction. In the following description, the control for stopping the reach-in operation of the mast 22 as the reach amount is equal to or smaller than the first threshold value Th1 will be referred to as a first control.

[0035] [Fork 26 stops descending] As shown in Fig. 5, when the forks 26 are loaded with luggage PG and the forks 26 and the reach legs 12 face each other in the vertical direction, the luggage PG may hit the upper surface SF2 of the reach leg 12 when the forks 26 are lowered. In this case, it is preferable that the lowering operation of the forks 26 is stopped so that the height of the forks 26 does not become smaller than the second threshold value Th2. The second threshold value Th2 is, for example, a value indicating the sum of the height of the reach leg 12 and the thickness of the pallet used by the forklift 10 to transport the luggage PG. In the following description, the control to stop the lowering operation of the forks 26 when the fork height is equal to or smaller than the second threshold value Th2 is referred to as the second control.

[0036] 4 and 5, the operation control unit 114 stops the reach-in operation of the mast 22 and stops the lowering operation of the forks 26. Hereinafter, the operation of the control device 100 will be described in detail with reference to a flowchart.

[0037] [flowchart] The flowchart shown in Fig. 6 is executed constantly or repeatedly at predetermined time intervals. The control device 100 executes controls related to the reach operation of the mast 22, the up and down operation of the forks 26, and the drive of the rear wheel 14 based on the operation of the operation unit 34 by the rider in parallel with the control of the flowchart shown in Fig. 6.

[0038] First, the operation control unit 114 determines whether or not baggage PG is loaded on the forks 26 based on the detection result of the loading sensor 40 acquired by the acquisition unit 112 (step S100). When the operation control unit 114 determines that baggage PG is loaded on the forks 26, it determines whether or not the occupant's operation on the operation unit 34 is an operation instructing a reach operation of the mast 22 (specifically, a reach-in operation) (step S102). When the operation control unit 114 determines that the occupant's operation on the operation unit 34 is not an operation instructing a reach operation of the mast 22, it determines whether or not the operation instructs an up-down operation of the forks 26 (specifically, a lowering operation) (step S104). When the operation control unit 114 determines that the reach operation of the mast 22 and the up-down operation of the forks 26 are not instructed, it advances the process to step S100.

[0039] When the operation control unit 114 determines that at least one of the reach operation of the mast 22 and the up / down operation of the forks 26 has been instructed, it determines whether or not the reach amount detected by the reach amount sensor 44 is equal to or less than the first threshold value Th1 (step S106). When the operation control unit 114 determines that the reach amount detected by the reach amount sensor 44 is not equal to or less than the first threshold value Th1, it advances the process to step S100.

[0040] When the operation control unit 114 determines that the reach amount detected by the reach amount sensor 44 is equal to or less than the first threshold value Th1, it determines whether or not the height of the forks 26 detected by the height sensor 42 is equal to or less than the second threshold value Th2 (step S108). When the operation control unit 114 determines that the height of the forks 26 detected by the height sensor 42 is not equal to or less than the second threshold value Th2, it advances the process to step S100.

[0041] When the operation control unit 114 determines that the reach amount is equal to or less than the first threshold value Th1 and that the height of the forks 26 is equal to or less than the second threshold value Th2, it executes the first control and stops the reach-in operation of the mast 22 (step S110). When the operation control unit 114 determines that the reach amount is equal to or less than the first threshold value Th1 and that the height of the forks 26 is equal to or less than the second threshold value Th2, it executes the second control and stops the lowering operation of the forks 26 (step S112). After executing the process of step S112, the operation control unit 114 advances the process to step S100.

[0042] [When either the first control or the second control is executed] In addition, the operation control unit 114 may execute only the first control when it determines that the reach amount is equal to or less than the first threshold value Th1, and may execute only the second control when it determines that the height of the fork 26 is equal to or less than the second threshold value Th2.

[0043] For example, in a situation where the operator of the forklift 10 can recognize the state of the upper surface SF2 of the reach leg 12 but has difficulty in recognizing the state of the front surface SF1 of the reach leg 12, the operation control unit 114 may execute only the first control without executing the second control. In this case, the operation control unit 114 does not execute the processes of steps S104, S108, and S112. In detail, when the operation control unit 114 determines in the process of step S102 that the reach operation of the mast 22 has not been instructed, the operation control unit 114 advances the process to step S100. Moreover, when the operation control unit 114 determines in the process of step S106 that the reach amount is equal to or less than the first threshold value Th1, the operation control unit 114 does not execute the process of step S108, but advances the process to step S110, and after executing the process of step S110, advances the process to step S100.

[0044] In addition, depending on the situation, when the operator of the forklift 10 can recognize the state of the front surface SF1 of the reach leg 12 but has difficulty in recognizing the state of the upper surface SF2 of the reach leg 12, the operation control unit 114 may execute only the second control without executing the first control. In this case, the operation control unit 114 does not execute the processes of steps S102, S106, and S110. In detail, when the operation control unit 114 determines in the process of step S100 that the baggage PG is loaded on the fork 26, the operation control unit 114 advances the process to step S104. When the operation control unit 114 determines in the process of step S104 that the height of the fork 26 is equal to or less than the second threshold value Th2, the operation control unit 114 does not execute the process of step S110 and advances the process to step S112. After executing the process of step S112, the operation control unit 114 advances the process to step S100.

[0045] [Effects of the forklift of this embodiment] According to the present embodiment described above in detail, the following effects are achieved. (1) When the detection result of the load sensor 40 indicates that luggage PG is loaded on the fork 26 and the reach amount detected by the reach amount sensor 44 is less than or equal to the first threshold value Th1, the operation control unit 114 executes a first control to stop the reach-in operation of the mast 22.

[0046] According to this configuration, when the driver of the forklift 10 mistakenly performs an excessive reach-in operation of the mast 22, the operation control unit 114 executes the first control to stop the mast 22 and prevent the cargo PG from hitting the front surface SF1 of the reach leg 12. Therefore, the forklift 10 can transport the cargo PG without causing damage to the cargo PG.

[0047] (2) When the detection result of the loading sensor 40 indicates that luggage PG is loaded on the forks 26 and the height of the forks 26 detected by the lifting height sensor 42 is below the second threshold value Th2, the operation control unit 114 executes a second control to stop the lowering operation of the forks 26.

[0048] According to this configuration, when the driver of the forklift 10 erroneously lowers the forks 26 too far, the operation control unit 114 executes the second control to stop the forks 26 and prevent the cargo PG from hitting the upper surface SF2 of the reach leg 12. Therefore, the forklift 10 can transport the cargo PG without damaging it.

[0049] [First threshold Th1 and second threshold Th2: size of forklift] The first threshold value Th1 and the second threshold value Th2 may be values ​​based on the size of the forklift 10, for example. In general, the larger the size of the forklift 10, the larger the load PG that the forklift 10 can transport. Load PG transported by a large forklift 10 is more likely to protrude beyond the forks 26 toward the mast 22 or below the upper surface of the forks 26 than load PG transported by a small forklift 10.

[0050] Hereinafter, a case will be described in which the first threshold value Th1 and the second threshold value Th2 are determined based on the largest luggage PG among the luggage PG that the forklift 10 can carry. In this case, the first threshold value Th1 is a value corresponding to the length between the position where the end of the luggage PG on the vehicle body 11 side is closest to the front surface SF1 of the reach leg 12 and does not contact the reach leg 12, and the position where the mast 22 is reached in the farthest and does not contact the vehicle body 11. The second threshold value Th2 is a value corresponding to the length from the position where the bottom of the luggage PG is closest to the upper surface SF2 of the reach leg 12 and does not contact the upper surface SF2 to the ground surface of the forklift 10 when the luggage PG is located above the reach leg 12. Therefore, the first threshold value Th1 and the second threshold value Th2 become larger as the size of the luggage PG increases in accordance with the size of the forklift 10.

[0051] The storage unit 200 stores a plurality of sets of threshold information, for example, first threshold information 202 and second threshold information 204, according to the size of the forklift 10. The control device 100 reads out from the storage unit 200, among the sets of threshold information stored in the storage unit 200, threshold information corresponding to the size of the forklift 10 on which the control device is mounted, and uses the read out threshold information for processing. The size of the forklift 10 may be specified at the time of shipment, or may be specified by referring to information indicating the size stored in a storage device such as the storage unit 200 provided in the forklift 10.

[0052] According to this configuration, the operation control unit 114 executes the first control and the second control based on the first threshold value Th1 and the second threshold value Th2, which are larger as the size of the forklift 10 increases. This allows the forklift 10 to transport a large load PG according to its own size without damaging the load PG.

[0053] [First threshold value Th1 and second threshold value Th2: Shape of luggage PG] The first threshold value Th1 and the second threshold value Th2 may be values ​​based on the shape of the luggage PG, for example. Here, the forklift 10 may transport luggage PG having a shape other than a square, such as having a convex portion or a concave portion. In detail, the forklift 10 may transport luggage PG having a shape that, when loaded onto the forks 26, protrudes beyond the forks 26 toward the mast 22 or protrudes below the upper surface of the forks 26.

[0054] In this case, the first threshold value Th1 is a value corresponding to the length between the position where the end of the luggage PG on the vehicle body 11 side is closest to the front surface SF1 of the reach leg 12 and does not contact the reach leg 12, and the position where the mast 22 is reached in furthest and does not contact the vehicle body 11. The second threshold value Th2 is a value corresponding to the length from the position where the bottom of the luggage PG is closest to the upper surface SF2 of the reach leg 12 and does not contact the upper surface SF2 to the ground surface of the forklift 10 when the luggage PG is located above the reach leg 12. Therefore, the first threshold value Th1 and the second threshold value Th2 become larger as the size of the luggage PG that can be loaded by the forklift 10 increases in accordance with the size of the forklift 10.

[0055] The storage unit 200 stores multiple sets of threshold information, for example, first threshold information 202 and second threshold information 204, according to the shape of luggage PG that the forklift 10 can transport. The control device 100 reads out from the storage unit 200, among the sets of threshold information stored in the storage unit 200, threshold information corresponding to the shape of luggage PG transported by the forklift 10 on which the control device is mounted, and uses the read out threshold information for processing. The shape of the luggage PG may be specified at the time of shipment or at the time of initial startup.

[0056] According to this configuration, the operation control unit 114 executes the first control and the second control based on the first threshold value Th1 and the second threshold value Th2 based on the shape of the luggage PG. This allows the forklift 10 to transport luggage PG without damaging it, even when the luggage PG has a shape other than a square.

[0057] [First threshold Th1 and second threshold Th2: Occupant designation] The first threshold value Th1 and the second threshold value Th2 may be specified by, for example, a driver of the forklift 10. In this case, as shown in Fig. 7, the forklift 10 further includes an input unit 60 that receives input from the driver. The input unit 60 is realized by, for example, an HMI (Human Machine Interface). The input unit 60 includes various display devices, speakers, buzzers, touch panels, switches, keys, etc.

[0058] As shown in FIG. 8, an image IM is displayed on the display device of the input unit 60 to prompt the occupant to input the first threshold value Th1 and the second threshold value Th2. The image IM includes, for example, a message MS prompting the occupant to input the first threshold value Th1 and the second threshold value Th2, a text box TX1, a text box TX2, and a numeric keypad image KY. The length of the luggage PG protruding from the fork 26 toward the vehicle body 11 is input in the text box TX1. The length of the luggage PG protruding downward from the bottom surface of the fork 26 is input in the text box TX2. The message MS is, for example, "Please input the amount of luggage protruding from the fork". The control device 100 stores information on the image IM in, for example, the storage unit 200, and causes the input unit 60 to display the image IM when the forklift 10 is started or when luggage PG is loaded onto the fork 26.

[0059] As shown in FIG. 9, in this case, the control unit 110 further includes a determination unit 118 in addition to the above-mentioned configuration. The determination unit 118 determines a first threshold value Th1 and a second threshold value Th2 based on an input to the input unit 60 acquired by the acquisition unit 112. For example, the determination unit 118 determines a value obtained by adding a value input to the text box TX1 and a value indicating the length of the reach leg 12 in the front-rear direction as the first threshold value Th1, and stores the determined first threshold value Th1 in the storage unit 200 as first threshold value information 202. The determination unit 118 determines a value obtained by adding a value input to the text box TX2 and a value indicating the height of the reach leg 12 as the second threshold value Th2, and stores the determined second threshold value Th2 in the storage unit 200 as second threshold value information 204.

[0060] In this case, the operation control unit 114 executes at least one of the first control and the second control based on the first threshold information 202 indicating the first threshold Th1 determined by the determination unit 118, and the second threshold information 204.

[0061] Here, the shape of the luggage PG transported by the forklift 10 may vary each time. In this case, it is preferable that the first threshold value Th1 and the second threshold value Th2 are specified each time according to the shape of the luggage PG to be transported. According to this configuration, the operation control unit 114 executes the first control and the second control based on the first threshold value Th1 and the second threshold value Th2 specified by the driver. As a result, the forklift 10 can transport luggage PG of different shapes each time without causing damage to the luggage PG.

[0062] Each embodiment can be modified as follows: The embodiments and the following modifications can be combined with each other to the extent that there is no technical contradiction. The height sensor 42 and the reach sensor 44 may be realized by a sensor other than a wire-type sensor. More specifically, they may be an optical sensor or an encoder capable of detecting the height and reach of the forks 26. They may also be an image processing device that captures images of the forks 26 and the mast 22 and processes the generated images to detect the height and reach of the forks 26.

[0063] The forklift 10 may be remotely operated. In this case, an operator operates the forklift 10 at a remote location away from the forklift 10. The operator operates an operation terminal provided at a remote location. As the operation terminal, a dedicated device or a mobile communication terminal such as a tablet terminal may be used. The operation terminal includes an operation unit that operates the forklift 10, an operation amount detection unit that detects the operation amount of the operation unit, and a communication device. The operation unit may be a physical member such as a lever, or may be a symbol that functions as the operation unit displayed on a touch panel. When the operation terminal displays a symbol that functions as the operation unit on a touch panel, the loading operation of the forklift 10 is performed by operating the touch panel. For example, the loading operation of the forklift 10 is performed by the operator's tap operation or slide operation on the touch panel. In this case, the operation amount is the number of taps or the amount of slide, and the touch panel functions as the operation amount detection unit. The communication device generates data in a predetermined format and transmits the data to the forklift 10. The communication device transmits information that allows the control device 100 to determine whether the operation unit is being operated, such as the operation amount of the operation unit. Therefore, the same control as when an operator is riding on the forklift 10 can be performed.

[0064] The forklift 10 includes an on-board communication device. The on-board communication device receives data transmitted from the communication device and outputs it to the control device 100. The control device 100 operates the forklift 10 according to the data transmitted from the communication device. The control device 100 controls the loading device 21 according to the operation of the operation unit. The control device 100 determines whether the operation unit is operated or not from the data transmitted from the communication device. In this case, it can be said that the on-board communication device functions as an acquisition unit. [Explanation of symbols]

[0065] 10...forklift, 11...vehicle body, 12...reach leg, 22...mast, 26...fork, PG...baggage, 34...operation unit, 40...load sensor, 42...lifting height sensor, 44...reach amount sensor, 114...motion control unit.

Claims

1. A forklift truck including a mast that moves forward and backward along a pair of left and right reach legs disposed forward of a vehicle body, and a pair of left and right forks disposed forward of the mast, a load sensor for detecting whether or not a load is loaded on the fork; An operation unit that receives an operation of the forklift by a driver; a reach amount sensor that detects the reach amount of the mast; A height sensor for detecting the height of the forks; and an operation control unit that controls a reach operation of the mast and controls an up-down operation of the fork along the mast based on the operation of the occupant received by the operation unit, the operation control unit executes at least one of a first control for stopping a reach-in operation of the mast when the detection result of the loading sensor indicates that the baggage is loaded on the forks and the reach amount detected by the reach amount sensor is equal to or less than a first threshold value, and a second control for stopping a lowering operation of the forks when the detection result of the loading sensor indicates that the baggage is loaded on the forks and the height detected by the height sensor is equal to or less than a second threshold value; The first threshold value and the second threshold value are values ​​based on a size of the host device, and the larger the size of the host device, the larger the values ​​are. A forklift truck characterized by:

2. A forklift truck including a mast that moves forward and backward along a pair of left and right reach legs disposed forward of a vehicle body, and a pair of left and right forks disposed forward of the mast, a load sensor for detecting whether or not a load is loaded on the fork; An operation unit that receives an operation of the forklift by a driver; a reach amount sensor that detects the reach amount of the mast; A height sensor for detecting the height of the forks; and an operation control unit that controls a reach operation of the mast and controls an up-down operation of the fork along the mast based on the operation of the occupant received by the operation unit, the operation control unit executes at least one of a first control for stopping a reach-in operation of the mast when the detection result of the loading sensor indicates that the baggage is loaded on the forks and the reach amount detected by the reach amount sensor is equal to or less than a first threshold value, and a second control for stopping a lowering operation of the forks when the detection result of the loading sensor indicates that the baggage is loaded on the forks and the height detected by the height sensor is equal to or less than a second threshold value; The first threshold value and the second threshold value are values ​​based on the shape of the baggage. A forklift truck characterized by:

3. The first threshold value and the second threshold value are values ​​based on the shape of the baggage.

2. The forklift according to claim 1.

4. an input unit that receives an input from the occupant specifying the first threshold value and the second threshold value; a determination unit that determines the first threshold value and the second threshold value based on an input to the input unit, The operation control unit executes at least one of the first control and the second control based on the first threshold value and the second threshold value determined by the determination unit. A forklift truck according to any one of claims 1 to 3.

5. A forklift truck including a mast that moves forward and backward along a pair of left and right reach legs disposed forward of a vehicle body, and a pair of left and right forks disposed forward of the mast, a load sensor for detecting whether or not a load is loaded on the fork; An operation unit that receives an operation of the forklift by a driver; a reach amount sensor that detects the reach amount of the mast; A height sensor for detecting the height of the forks; and an operation control unit that controls a reach operation of the mast and controls an up-down operation of the fork along the mast based on the operation of the occupant received by the operation unit, the operation control unit executes at least one of a first control for stopping a reach-in operation of the mast when the detection result of the loading sensor indicates that the baggage is loaded on the forks and the reach amount detected by the reach amount sensor is equal to or less than a first threshold value, and a second control for stopping a lowering operation of the forks when the detection result of the loading sensor indicates that the baggage is loaded on the forks and the height detected by the height sensor is equal to or less than a second threshold value; an input unit that receives an input from the occupant specifying the first threshold value and the second threshold value; a determination unit that determines the first threshold value and the second threshold value based on an input to the input unit, The operation control unit executes at least one of the first control and the second control based on the first threshold value and the second threshold value determined by the determination unit. A forklift truck characterized by:

6. The reach amount sensor and the lift height sensor are wire-type sensors. A forklift truck according to any one of claims 1 to 5.

7. A forklift truck including a mast that moves forward and backward along a pair of left and right reach legs disposed forward of a vehicle body, and a pair of left and right forks disposed forward of the mast, a load sensor for detecting whether or not a load is loaded on the fork; An operation unit that receives an operation of the forklift by a driver; a reach amount sensor that detects the reach amount of the mast; A height sensor for detecting the height of the forks; and an operation control unit that controls a reach operation of the mast and controls an up-down operation of the fork along the mast based on the operation of the occupant received by the operation unit, the operation control unit executes at least one of a first control for stopping a reach-in operation of the mast when the detection result of the loading sensor indicates that the baggage is loaded on the forks and the reach amount detected by the reach amount sensor is equal to or less than a first threshold value, and a second control for stopping a lowering operation of the forks when the detection result of the loading sensor indicates that the baggage is loaded on the forks and the height detected by the height sensor is equal to or less than a second threshold value; The reach amount sensor and the lift height sensor are wire-type sensors. A forklift truck characterized by:

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