JP2022190544A - forklift - Google Patents

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

The present invention relates to forklifts.

Conventionally, there is known a technique of transporting cargo by a forklift without damaging it (see, for example, Patent Literature 1).

Japanese Patent Application Laid-Open No. 2006-206243

Here, when a crew member operates a reach-type forklift truck, in the reach-out state, there is a case where the load hits the reach leg by erroneously operating the reach-out state and causing the mast to reach-in while the forks are lowered. Further, when a crew member operates a reach-type forklift truck, if the fork is lowered by mistake in the reach-in state, the load may hit the reach leg. Therefore, when an occupant operates a reach-type forklift, it may be difficult to carry the load without hitting the reach leg.

A forklift that achieves the above object is a forklift that includes a mast that moves back and forth along a pair of left and right reach legs arranged in front of the vehicle body, and a pair of left and right forks in front of the mast, A load sensor that detects whether or not a load is loaded, an operation unit that receives an operator's operation of the forklift, a reach sensor that detects the reach of the mast, and a lift that detects the height of the fork. a sensor; and an operation control unit that controls the reach operation of the mast and controls the up-and-down operation of the fork along the mast based on the occupant's operation received by the operation unit, wherein the operation control unit When the detection result of the load sensor indicates that the cargo is loaded on the fork and the reach amount detected by the reach amount sensor is equal to or less than a first threshold value, the mast A first control for stopping the reach-in operation, a detection result of the load sensor indicating that the load is loaded on the forks, and a height detected by the lift sensor being equal to or less than a second threshold. In this case, at least one of second control for stopping the lowering operation of the fork is executed.

According to such a configuration, the operation control unit stops the operation of the mast and fork so that the load does not hit the reach leg even if the passenger makes an erroneous operation. This allows the forklift to transport the load without damaging it.

In the above forklift truck, the first threshold value and the second threshold value are values based on the size of the own device, and the larger the size of the own device, the larger the value.
In general, the larger the forklift, the larger the load it can carry. According to such a configuration, the operation control unit executes the first control and the second control based on the first and second thresholds having larger values as the size of the forklift is larger. As a result, the forklift 10 can carry a load without damaging it, even if the load is large according to the size of the forklift truck 10 itself.

In the above forklift, the first threshold value and the second threshold value are values based on the shape of the load.
According to such a configuration, the operation control unit stops the operation of the mast and the fork based on the first threshold value and the second threshold value according to the shape of the cargo, so that the cargo can be transported without being damaged. can.

In the forklift, an input unit that receives input from the occupant specifying the first threshold value and the second threshold value, and a determination that determines the first threshold value and the second threshold value based on the input to the input unit. and the operation control unit performs at least one of the first control and the second control based on the first threshold and the second threshold determined by the determination unit. It is characterized by executing control.

According to such a configuration, the operation control unit can stop the operation of the mast and fork based on the first threshold value and the second threshold value desired by the occupant, and can transport the cargo without damaging it.

In the above forklift, the reach sensor and the height sensor are wire sensors.

According to the present invention, a reach-type forklift truck can carry a load without hitting the reach leg.

Side view of a forklift. A perspective view of a forklift. The figure which shows the structure of a control apparatus. The figure used for description of the scene which stops reach operation|movement. The figure used for description of the scene which stops the up-and-down motion of a fork. 4 is a flowchart showing an example of control by the control device; A perspective view of a forklift. The figure which shows an example of a display image. The figure which shows the structure of a control apparatus.

<Embodiment>
An embodiment of a forklift truck according to the present invention will be described below with reference to the drawings.
[Configuration of forklift 10]
As shown in FIGS. 1 and 2, the forklift 10 includes, for example, a vehicle body 11, a reach leg 12, a front wheel 13, a rear wheel 14, a cargo handling device 21, an operation unit 34, a load sensor 40, and a lifting height. A sensor 42 and a reach sensor 44 are provided. The forklift 10 also includes, for example, a hydraulic mechanism 52 and a control device 100 . The forklift 10 may be manually operated by an operator on board the forklift 10, or may be switched between automatic operation and manual operation. That is, the forklift 10 may be any one that can be manually operated by the operator. In the following description, front, rear, left, right, up and down refer to front, rear, left, right, up and down with respect to the forklift 10 . The front-rear direction can also be said to be the traveling direction of the forklift 10 . The left-right direction can also be said to be the vehicle width direction of the forklift 10 . The vertical direction can also be said to be the height direction of the forklift 10 .

The reach leg 12 is arranged forward of the vehicle body 11 . Two reach legs 12 are provided so as to be separated from each other in the left-right direction. A pair of left and right reach legs 12 extend forward from the vehicle body 11 . One front wheel 13 is provided for each reach leg 12 . The rear wheels 14 are provided on the vehicle body 11 . The rear wheels 14 are, for example, steering wheels and driving wheels.

The cargo handling device 21 is provided forward of the vehicle body 11 . The cargo handling 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 .

Mast 22 is a multistage mast. The mast 22 has an outer mast 23 and an inner mast 24 . The inner mast 24 is provided so as to be able to move up and down with respect to the outer mast 23 .

A lift bracket 25 is fixed to the inner mast 24 . A fork 26 is secured to the lift bracket 25 . Two forks 26 are provided so as to be separated 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 .

The lift cylinder 31 is a hydraulic cylinder. The lift bracket 25 moves up and down by supplying and discharging working oil to the lift cylinder 31 . The fork 26 moves up and down together with the lift bracket 25.

The tilt cylinder 32 is a hydraulic cylinder. The lift bracket 25 tilts in the front-rear direction by supplying and discharging working oil to the tilt cylinder 32 . The tilt includes a forward tilt that tilts the lift bracket 25 forward and a rearward tilt that tilts the lift bracket 25 backward. Fork 26 tilts together with lift bracket 25 .

The reach cylinder 33 is a hydraulic cylinder. The mast 22 moves in the front-rear direction by supplying and discharging working oil to the reach cylinder 33 . The fork 26 moves forward and backward together with the mast 22 . Hereinafter, advancing the fork 26 by the reach cylinder 33 is called reach-out operation, and retreating the fork 26 by the reach cylinder 33 is called reach-in operation.

The operation unit 34 receives an operation by an occupant on the forklift 10 . The operating section 34 includes a lift operating section 35 , a tilt operating section 36 and a reach operating section 37 . The lift operation unit 35 is operated by the crew of the forklift 10 . The lift operation part 35 of this embodiment is a lever. The lift operation unit 35 tilts forward or backward from the neutral position. The lift operation unit 35 is operated by the crew of the forklift 10 when the forks 26 are raised and lowered.

The tilt operation unit 36 is operated by the crew of the forklift 10 . The tilt operation unit 36 of this embodiment is a lever. The tilt operation unit 36 tilts forward or backward from the neutral position. The tilt operation part 36 is operated by the passenger of the forklift 10 when tilting the fork 26 .

The reach operation unit 37 is operated by the crew of the forklift 10 . The reach operating portion 37 of this embodiment is a lever. The reach operating portion 37 tilts forward or backward from the neutral position. The reach operation part 37 is operated by the crew of the forklift 10 when moving the forks 26 in the front-rear direction.

The loading sensor 40 detects whether or not the forks 26 are loaded with cargo. The loading sensor 40 is implemented by, for example, a lever-type sensor that is pushed down when the fork 26 is loaded with cargo. The load sensor 40 supplies the control device 100 with information indicating that the fork 26 is loaded with a load.

A lift sensor 42 detects the height of the fork 26 lifted by the lift cylinder 31 . The height of the fork 26 is, for example, the height from the ground surface of the forklift 10 to the surface of the fork 26 on which a load is loaded. The elevation sensor 42 is implemented by, for example, a wire sensor. Specifically, the height sensor 42 detects the height of the fork 26 based on the amount of wire that is pulled out as the fork 26 is lifted and wound as the fork 26 is lowered. For example, the height of the fork 26 takes the smallest value when the fork 26 is moved to the lowest position, and takes the largest value when the fork 26 is moved to the highest position. The height sensor 42 supplies information indicating the detected height of the fork 26 to the control device 100 .

The reach 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 reach amount. The reach sensor 44 is implemented by, for example, a wire sensor. Specifically, the reach amount sensor 44 detects the reach amount based on the amount of wire pulled out according to the reach-out operation of the mast 22 and wound up according to the reach-in operation of the mast 22 . The reach amount takes the smallest value, for example, when the mast 22 is moved to the position closest to the vehicle body 11, and the mast 22 is located at the end of the reach leg 12 opposite to the end on the vehicle body 11 side. Takes the largest value when moved to the end. The reach amount sensor 44 supplies information indicating the detected reach amount to the control device 100 .

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

The control device 100 controls each part of the forklift 10 . Details of the control device 100 will be described below.
[Configuration of control device]
As shown in FIG. 3, the control device 100 is connected to the operation section 34, the load sensor 40, the height sensor 42, and the reach sensor 44, and the control device 100 acquires various information from each section. A hydraulic mechanism 52 is connected to the control device 100, and the control device 100 controls each part.

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

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

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

The motion control unit 114 controls the reach motion of the mast 22 based on the operation of the occupant of the forklift 10 received by the operation unit 34 , and controls the vertical motion of the fork 26 along the mast 22 .

[Stop reach operation]
As shown in FIG. 4, when the forks 26 are loaded with the cargo PG and the height of the forks 26 is lower than the height of the reach leg 12, when the mast 22 is moved toward the vehicle body 11, the front surface SF1 of the reach leg 12 may be hit by the baggage PG. In this case, the reach-in operation of the mast 22 is preferably stopped so that the reach amount does not become smaller than the first threshold value Th1. The first threshold Th1 is, for example, a value indicating the length of the reach leg 12 in the front-rear direction. In the following description, control for stopping the reach-in operation of the mast 22 when the reach amount is equal to or less than the first threshold value Th1 is referred to as first control.

[Stopping the lowering operation of the fork 26]
As shown in FIG. 5, when the fork 26 and the reach leg 12 face each other vertically with the load PG loaded on the fork 26, when the fork 26 is lowered, the load PG hits the upper surface SF2 of the reach leg 12. may be lost. In this case, the fork 26 is preferably stopped from descending so that the height of the fork 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 load PG. In the following description, control for stopping the lowering operation of the fork 26 when the fork height is equal to or less than the second threshold Th2 is referred to as second control.

The motion control unit 114 stops the reach-in motion of the mast 22 and the lowering motion of the fork 26 in the scenes shown in FIGS. 4 and 5 . Details of the operation of the control device 100 will be described below with reference to flowcharts.

[flowchart]
The flowchart shown in FIG. 6 is repeatedly executed at all times or at predetermined time intervals. The control device 100 controls the reach operation of the mast 22, the up-down operation of the fork 26, and the drive of the rear wheel 14 based on the operation of the occupant on the operation unit 34, separately from the flowchart shown in FIG. It is executed concurrently with the control of the flow chart shown.

First, the operation control unit 114 determines whether or not the load PG is loaded on the fork 26 based on the detection result of the load sensor 40 acquired by the acquisition unit 112 (step S100). When the motion control unit 114 determines that the cargo PG is loaded on the forks 26, the crew member's operation on the operation unit 34 is an operation to instruct the reach operation (specifically, the reach-in operation) of the mast 22. It is determined whether or not (step S102). When the operation control unit 114 determines that the occupant's operation on the operation unit 34 does not instruct the reaching operation of the mast 22, the operation control unit 114 instructs the fork 26 to move up and down (specifically, to move down). It is determined whether or not there is (step S104). If the operation control unit 114 determines that the reach operation of the mast 22 and the vertical operation of the fork 26 have not been instructed, the process proceeds to step S100.

When the operation control unit 114 determines that at least one of the reach operation of the mast 22 and the vertical operation of the fork 26 is instructed, the reach amount detected by the reach amount sensor 44 is equal to or less than the first threshold value Th1. It is determined whether or not there is (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, the process proceeds to step S100.

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 Th1, the height of the fork 26 detected by the lift sensor 42 is equal to or less than the second threshold Th2. It is determined whether or not (step S108). If the motion control unit 114 determines that the height of the forks 26 detected by the lift sensor 42 is not equal to or less than the second threshold Th2, the process proceeds to step S100.

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

[When executing one of the first control and the second control]
In addition, when the reach amount is determined to be equal to or less than the first threshold Th1, the operation control unit 114 may execute only the first control. If so, only the second control may be executed.

For example, when the occupant of the forklift 10 can recognize the state of the upper surface SF2 of the reach leg 12 depending on the situation, but it is difficult to recognize the state of the front surface SF1 of the reach leg 12, the operation control unit 114 does not execute the second control, Only the first control may be executed. In this case, the operation control unit 114 does not execute the processes of steps S104, S108, and S112. Specifically, when the operation control unit 114 determines in the process of step S102 that the reaching operation of the mast 22 has not been instructed, the process proceeds to step S100. Further, when it is determined in 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, proceeds to step S110, and executes the process of step S110. After that, the process proceeds to step S100.

In addition, when the occupant of the forklift 10 can recognize the state of the front surface SF1 of the reach leg 12 depending on the situation, but it is difficult to recognize the state of the upper surface SF2 of the reach leg 12, the operation control unit 114 does not execute the first control. Only the second control may be executed. In this case, the operation control unit 114 does not execute the processes of steps S102, S106, and S110. Specifically, when the operation control unit 114 determines in the process of step S100 that the load PG is loaded on the forks 26, the process proceeds to step S104. If the motion control unit 114 determines in step S104 that the height of the fork 26 is equal to or less than the second threshold value Th2, the process proceeds to step S112 without executing the process of step S110. After executing the process of step S112, the operation control unit 114 advances the process to step S100.

[About the effects of the forklift of the present embodiment]
According to this embodiment detailed above, the following effects are obtained.
(1) The operation control unit 114 determines that the detection result of the load sensor 40 indicates that the load PG is loaded on the forks 26, and the reach amount detected by the reach amount sensor 44 is equal to or less than the first threshold value Th1. When indicating that, the first control for stopping the reach-in operation of the mast 22 is executed.

According to this configuration, when the occupant of the forklift 10 erroneously causes the mast 22 to reach-in excessively, the operation control unit 114 stops the mast 22 by executing the first control, and the front surface SF1 of the reach leg 12 to prevent the baggage PG from hitting the . Therefore, the forklift 10 can transport the cargo PG without damaging it.

(2) The operation control unit 114 determines that the detection result of the load sensor 40 indicates that the load PG is loaded on the forks 26, and that the height of the forks 26 detected by the lifting height sensor 42 exceeds the second threshold value Th2. When indicating the following, the second control is executed to stop the lowering operation of the fork 26 .

According to this configuration, when the occupant of the forklift 10 erroneously lowers the fork 26 too much, the operation control unit 114 stops the fork 26 by executing the second control, and the upper surface SF2 of the reach leg 12 is detected. to prevent the baggage PG from hitting the . Therefore, the forklift 10 can transport the cargo PG without damaging it.

[First Threshold Th1 and Second Threshold Th2: Size of Forklift]
The first threshold Th1 and the second threshold Th2 may be values based on the size of the forklift 10, for example. In general, the larger the forklift 10, the larger the load PG it can carry. A load PG carried by a large forklift 10 may protrude from the fork 26 to the mast 22 side or protrude below the upper surface of the fork 26 compared to the load PG carried by the small forklift 10. - 特許庁

A case where the first threshold value Th1 and the second threshold value Th2 are determined based on the largest load PG among the loads PG that can be loaded by the forklift 10 will be described below. In this case, the first threshold value Th1 is determined by the position where the end of the cargo PG on the vehicle body 11 side is closest to the front surface SF1 of the reach leg 12 and does not touch the reach leg 12, and the position where the mast 22 is most reach-in. , and a position not in contact with the vehicle body 11 . Further, the second threshold Th2 is the case where the load PG is above the reach leg 12, and the bottom of the load PG is closest to the top surface SF2 of the reach leg 12 and does not come into contact with the top surface SF2. is a value corresponding to the length up to . Therefore, the first threshold value Th1 and the second threshold value Th2 become larger values as the size of the load PG increases as the size of the forklift 10 increases.

The storage unit 200 stores, for example, a plurality of sets of threshold information including first threshold information 202 and second threshold information 204 according to the size of the forklift 10 . The control device 100 reads, from the storage unit 200, threshold information corresponding to the size of the forklift 10 on which the control device 100 is mounted, among the set of threshold information stored in the storage unit 200, and uses it 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 included in the forklift 10 .

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 that are larger as the size of the forklift 10 is larger. As a result, the forklift 10 can carry the load PG without damaging it, even when the load PG is large according to the size of the forklift truck 10 itself.

[First Threshold Th1 and Second Threshold Th2: Shape of Baggage PG]
Also, the first threshold Th1 and the second threshold Th2 may be values based on the shape of the package PG, for example. Here, the forklift 10 may transport a load PG having a shape other than square, such as having a convex portion or a concave portion. More specifically, the forklift 10 may carry a load PG that, when loaded on the forks 26, protrudes from the forks 26 to the mast 22 side or protrudes below the upper surface of the forks 26.例文帳に追加

In this case, the first threshold value Th1 is determined by the position where the end of the cargo PG on the vehicle body 11 side is closest to the front surface SF1 of the reach leg 12 and does not touch the reach leg 12, and the position where the mast 22 is most reach-in. , and a position not in contact with the vehicle body 11 . Further, the second threshold Th2 is the case where the load PG is above the reach leg 12, and the bottom of the load PG is closest to the top surface SF2 of the reach leg 12 and does not come into contact with the top surface SF2. is a value corresponding to the length up to . Therefore, the first threshold value Th1 and the second threshold value Th2 become larger values as the size of the load PG that can be loaded by the forklift 10 increases as the size of the forklift 10 increases.

The storage unit 200 stores, for example, a plurality of threshold information sets of first threshold information 202 and second threshold information 204 according to the shape of the load PG that the forklift 10 can carry. Of the set of threshold information stored in the storage unit 200, the control device 100 reads, from the storage unit 200, threshold information corresponding to the shape of the load PG carried by the forklift 10 on which the control device 100 is mounted, and uses it for processing. The shape of the parcel PG may be specified at the time of shipment or may be specified at the time of initial startup.

According to this configuration, the operation control unit 114 executes the first control and the second control based on the first threshold Th1 and the second threshold Th2 based on the shape of the package PG. As a result, the forklift 10 can carry a load PG having a shape other than a square shape without damaging the load PG.

[First Threshold Th1 and Second Threshold Th2: Occupant Designation]
Also, the first threshold Th1 and the second threshold Th2 may be specified by the crew member of the forklift 10, for example. In this case, as shown in FIG. 7, the forklift 10 further includes an input unit 60 that receives input from the passenger. The input unit 60 is implemented by, for example, an HMI (Human Machine Interface). The input unit 60 includes various display devices, speakers, buzzers, touch panels, switches, keys, and the like.

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

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

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

Here, the shape of the load PG transported by the forklift 10 may differ each time. In this case, the first threshold value Th1 and the second threshold value Th2 are preferably designated each time according to the shape of the load 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 Th1 and the second threshold Th2 specified by the occupant. As a result, the forklift 10 can carry the load PG without damaging it, even when the load PG has a different shape each time.

Each embodiment can be modified and implemented as follows. The embodiments and the following modifications can be implemented in combination with each other within a technically consistent range.
O The lift sensor 42 and the reach sensor 44 may be implemented by sensors other than wire sensors. Specifically, it may be an optical sensor or an encoder capable of detecting the height and reach of the fork 26 . Alternatively, the image processing device may detect the height and reach of the fork 26 by imaging the fork 26 and the mast 22 and processing the generated image.

o The forklift 10 may be remotely operated. In this case, the operator operates the forklift 10 at a remote location away from the forklift 10 . An operator operates an operation terminal provided at a remote location. As the operation terminal, a dedicated device can be used, or a mobile communication terminal such as a tablet terminal can be used. The operation terminal includes an operation unit that operates the forklift 10, an operation amount detection unit that detects an 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 touch panel displaying a symbol that functions as the operation unit. When the operation terminal displays a symbol functioning as an operation unit on the touch panel, the cargo handling operation of the forklift 10 is performed by operating the touch panel. For example, the cargo handling operation of the forklift 10 is performed by an 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 an operation amount detection unit. The communication device generates data in a predetermined format and transmits this data to the forklift 10 . The communication device transmits information that allows the control device 100 to determine whether or not the operation unit is being operated, such as the operation amount of the operation unit. Therefore, the same control can be performed as when the crew is on the forklift 10 .

The forklift 10 includes an in-vehicle communication device. The in-vehicle communication device receives data transmitted from the communication device and outputs the data 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 cargo handling device 21 according to the operation of the operation unit. The control device 100 determines whether or not the operation unit is being operated from the data transmitted from the communication device. in this case. It can be said that the in-vehicle communication device functions as an acquisition unit.

DESCRIPTION OF SYMBOLS 10... Forklift, 11... Vehicle body, 12... Reach leg, 22... Mast, 26... Fork, PG... Load, 34... Operation part, 40... Loading sensor, 42... Lifting height sensor, 44... Reach amount sensor, 114... Operation control Department.

Claims (5)

A forklift having a mast that moves back and forth along a pair of left and right reach legs arranged in front of a vehicle body, and a pair of left and right forks in front of the mast,
a load sensor that detects whether or not a load is loaded on the fork;
an operation unit that receives a crew member's operation of the forklift;
a reach sensor for detecting the reach of the mast;
a lift sensor that detects the height of the fork;
an operation control unit that controls the reach operation of the mast and controls the up-down operation of the fork along the mast based on the occupant's operation received by the operation unit;
When the detection result of the load sensor indicates that the cargo is loaded on the fork and the reach amount detected by the reach amount sensor is equal to or less than a first threshold value. a first control for stopping the reach-in operation of the mast; a detection result of the load sensor indicating that the load is loaded on the forks; When indicating that it is below the threshold, at least one of the second control for stopping the lowering operation of the fork is executed.
A forklift characterized by: The first threshold and the second threshold are values based on the size of the device itself, and the larger the size of the device itself, the larger the value.
A forklift according to claim 1. The first threshold and the second threshold are values based on the shape of the package,
A forklift according to claim 1 or 2. an input unit that receives input from the occupant designating the first threshold and the second threshold;
A determination unit that determines the first threshold and the second threshold based on the input to the input unit,
The operation control unit performs 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 according to any one of claims 1 to 3. The reach sensor and the lift sensor are wire sensors,
A forklift according to any one of claims 1 to 4.

Images