Forklift, forklift control system, weight detection device, weight detection method, and weight detection program

Abstract

A forklift according to an embodiment includes a traveling body, a fork, and a sensor. The fork is provided in front of the traveling vehicle body, and has a recess at least at a distal end thereof. The sensor is housed in the recessed portion and detects a condition around the tip portion.

Description

Technical Field

[0001] The disclosed technical solution relates to a forklift, a control system of the forklift, a weight detection device, a weight detection method, and a weight detection program. Background Art

[0002] In the prior art, a forklift has been proposed that uses a camera provided at the base end of a fork to photograph the end side of the fork and automatically controls the fork (for example, refer to Patent Document 1).

[0003] Prior Art Documents

[0004] Patent Documents

[0005] Patent Document 1: Japanese Unexamined Patent Application Publication No. 2022-17613.

[0006] However, in the existing technology, since the fork is photographed from the base end side of the fork, the fork itself is included in the photographed image, and thus the condition of the end of the fork shown in the photographed image may be obstructed by the fork. Summary of the Invention

[0007] The present invention has been made in view of the above circumstances, and an object thereof is to provide a forklift, a control system of the forklift, a weight detection device, a weight detection method, and a weight detection program that can more accurately grasp the condition of the end of the fork.

[0008] A forklift according to one aspect of the technical solution includes a traveling vehicle body, a fork, and a sensor. The fork is provided in front of the traveling vehicle body and has a concave portion at least at the end portion. The sensor is accommodated in the concave portion and detects the condition around the end portion.

[0009] (Advantages of the Invention)

[0010] According to one aspect of the technical solution, the condition of the end of the fork can be more accurately grasped. Brief Description of the Drawings

[0011] Figure 1 It is a schematic side view of a forklift according to the first embodiment.

[0012] Figure 2 It is a diagram showing an example of the arrangement of a condition detection sensor.

[0013] Figure 3 It is a block diagram showing an example of the functional configuration of a control device.

[0014] Figure 4 It is a block diagram showing an example of the functional configuration of a weight detection device.

[0015] Figure 5 It is a diagram showing an example of associated information.

[0016] Figure 6 is a flowchart showing the processing procedure of the processing executed by the control device according to the first embodiment.

[0017] Figure 7 is a flowchart showing the processing procedure of the processing executed by the weight detection device according to the first embodiment.

[0018] Figure 8 is a diagram showing an example of the arrangement of the condition detection sensor according to a modification of the first embodiment.

[0019] Figure 9 is a diagram showing an example of the arrangement of the condition detection sensor according to a modification of the first embodiment.

[0020] Figure 10 is a schematic side view of the forklift according to the second embodiment.

[0021] Figure 11 is a diagram showing an example of the configuration of the window portion according to the second embodiment.

[0022] Figure 12 is a diagram (part 1) showing an example of the condition detection at the fork tip according to the second embodiment.

[0023] Figure 13 is a diagram (part 2) showing an example of the condition detection at the fork tip according to the second embodiment.

[0024] Figure 14 is a diagram showing an example of the width adjustment of the fork according to the second embodiment.

[0025] Figure 15 is a diagram showing an example of the configuration of the window portion according to a modification of the second embodiment.

[0026] Figure 16 is a diagram showing the control system of the forklift according to the third embodiment.

[0027] Figure 17 is a diagram (part 1) showing the fork insertion hole detection portion according to the third embodiment.

[0028] Figure 18 is a diagram (part 2) showing the fork insertion hole detection portion according to the third embodiment.

[0029] Figure 19 is a diagram showing the fork insertion hole detection portion according to Modification 1 of the third embodiment.

[0030] Figure 20 is a diagram showing the fork insertion hole detection portion according to Modification 2 of the third embodiment.

[0031] Figure 21 This is a diagram showing an overview of the forklift according to the fourth embodiment.

[0032] Figure 22 This is a diagram showing an example of the condition detection of the fork tip according to the fourth embodiment.

[0033] Figure 23 This is a diagram showing another example of the condition detection of the fork tip according to the fourth embodiment.

[0034] Figure 24 This is a flowchart showing an example of the process of the processing executed by the control device according to the fourth embodiment.

[0035] Figure 25 This is a schematic side view of the forklift according to the fifth embodiment.

[0036] Figure 26 This is a schematic top view of the forklift according to the fifth embodiment.

[0037] Figure 27 This is a flowchart explaining the detection process according to the fifth embodiment.

[0038] Figure 28 This is a diagram showing the state where the fork is tilted upward according to the sixth embodiment.

[0039] Figure 29 This is a flowchart explaining the travel permission process according to the sixth embodiment.

[0040] Figure 30 This is a diagram schematically showing an example of the hardware configuration of a computer that functions as a control device and / or a weight detection device. Detailed Embodiments

[0041] Hereinafter, the present invention will be described by way of embodiments. However, the following embodiments do not limit the invention claimed. In addition, the combinations of the features described in the embodiments are not necessarily all essential for the technical solution of the invention.

[0042] (First Embodiment)

[0043] Figure 1 This is a schematic side view of the forklift 1 according to the first embodiment. Figure 1 The shown forklift 1 is a schematic diagram, and a part of the configuration is omitted for convenience of explanation. In addition, the forklift 1 shown in the present disclosure travels by automatic control. That is, the forklift 1 shown in the present disclosure transports the load by autonomous driving without a driver. In addition, the forklift 1 is not limited to being unmanned, and may be configured for manual driving by a person. Alternatively, the forklift 1 may be configured to be able to switch between an unmanned mode and a manned mode.

[0044] As shown in Figure 1 Figure 1, the forklift 1 includes a traveling vehicle body 2, a fork 3, a lifting unit 4, a condition detection sensor 5, a load sensor 6, a control device 10, and a weight detection device 20.

[0045] The traveling vehicle body 2 is a vehicle body that travels on a road surface R in a warehouse or the like. The traveling vehicle body 2 drives the wheels in contact with the road surface R to travel on the road surface R.

[0046] The fork 3 is a member for placing a pallet loaded with a load, and is composed of a pair (i.e., two members) on the left and right. The fork 3 is lifted by being inserted into the fork insertion holes provided in the pallet to carry the pallet.

[0047] The lifting unit 4 raises and lowers the fork 3 in accordance with the control of the control device 10. Thereby, the height position of the fork 3 can be changed.

[0048] The condition detection sensor 5 is a sensor provided at the distal end portion of the fork 3 and for detecting the condition around the distal end portion of the fork 3. The condition detection sensor 5 is, for example, a camera, a Lidar (Light Detection And Ranging), a radar device, or the like.

[0049] The load sensor 6 is a sensor for detecting the load applied to the fork 3. When a pallet is placed on the fork 3, the load sensor 6 detects the total weight of the pallet and the load as the load.

[0050] The control device 10 is a control device for controlling the entire forklift 1. Specifically, the control device 10 controls the wheels of the traveling vehicle body 2 to control the automatic traveling on the road surface R. In addition, the control device 10 controls the lifting unit 4 to control the automatic lifting of the fork 3. In addition, the detailed configuration and processing of the control device 10 will be described later.

[0051] The weight detection device 20 detects the weight of the pallet and the load placed on the fork 3. Specifically, the weight detection device 20 detects the weight of the pallet, the weight of the load, the weight of the outer packaging of the load, the weight of the contents of the load, and the like. In addition, the method for detecting the weight performed by the weight detection device 20 will be described later.

[0052] Next, Figure 2 a setting example of the condition detection sensor 5 will be described using Figure 2 FIG. 2 is a diagram showing a setting example of the condition detection sensor 5. In Figure 2 FIG. 2, a view of the fork 3 as viewed from the distal end side toward the proximal end side (viewed from the negative X-axis direction) is shown.

[0053] As shown in Figure 2As shown, the fork 3 has a recess 3a at least at its end portion. The condition detection sensor 5 is arranged to be received in the recess 3a. Specifically, the recess 3a of the fork 3 is shaped such that the portion on the road surface R side (negative Y-axis direction side) where the traveling vehicle body 2 travels is recessed. That is, the condition detection sensor 5 is arranged on the road surface R side of the fork 3. Thus, even when a tray is placed on the fork 3, contact between the condition detection sensor 5 and the tray can be avoided.

[0054] In addition, as Figure 2 shown, the depth (length in the Y-axis direction) of the recess 3a is longer than the height (length in the Y-axis direction) of the condition detection sensor 5. That is, the end on the road surface R side of the recess 3a is closer to the road surface R than the end on the road surface side of the condition detection sensor 5. Thus, even when an object contacts from the road surface R side of the fork 3, contact between the object and the condition detection sensor 5 can be avoided.

[0055] In addition, as Figure 1 shown, the end of the fork 3 is located in front (negative X-axis direction side) compared to the condition detection sensor 5. Thus, even when an object contacts from the end of the fork 3, contact between the object and the condition detection sensor 5 can be avoided.

[0056] In addition, by arranging the condition detection sensor 5 at the end of the fork 3, information of the fork 3 is not included in the detection result of the condition detection sensor 5 (the fork 3 is not captured in the captured image), so that the condition at the end of the fork can be grasped more accurately.

[0057] As a result, even in a situation where, for example, a tray is placed at a high position (a position higher than the operator's line of sight height), the fork 3 can be reliably inserted into the tray.

[0058] Furthermore, the recess 3a may be shaped such that only the place where the condition detection sensor 5 is arranged is recessed, or may be shaped such that the portion on the road surface R side in the fork 3 is recessed as a whole. In other words, the recess 3a may be shaped to be recessed from the end portion of the fork 3 to the base end portion on the traveling vehicle body 2 side. Thus, the position in the front-rear direction (X-axis direction) of the condition detection sensor 5 can be adjusted.

[0059] Furthermore, the recess 3a is not limited to being arranged at the portion on the road surface R side in the fork 3, and the surface on the front side (negative X-axis direction side) in the fork 3 may be recessed.

[0060] Next, Figure 3 and Figure 4 are used to illustrate a functional configuration example of the control device 10 and the weight detection device 20. Figure 3 is a block diagram showing a functional configuration example of the control device 10. Figure 4 is a block diagram showing a functional configuration example of the weight detection device 20.

[0061] First, use Figure 3 to illustrate an example of the functional configuration of the control device 10. As Figure 3 shown, the control device 10 includes a communication unit 11, a control unit 12, and a storage unit 13. The control unit 12 includes a detection unit 121 and an operation control unit 122.

[0062] The communication unit 11 is implemented, for example, by a NIC (Network Interface Card). The communication unit 11 is connected to a network via wire or wirelessly. For example, the communication unit 11 is connected to a server device that manages the forklift 1 in a communicable manner.

[0063] The control unit 12 automatically controls the traveling vehicle body 2 and the fork 3 (lifting unit 4) based on the information detected by the condition detection sensor 5.

[0064] The detection unit 121 detects the condition around the end of the fork 3 based on the information detected by the condition detection sensor 5. For example, the detection unit 121 detects a captured image captured by a camera, information (position information, shape information) of a target detected by a Lidar or radar device as the surrounding condition.

[0065] In addition, the detection unit 121 detects pallets existing around the forklift 1 based on the captured image and the information of the target. For example, the detection unit 121 detects the number of pallets and the positions of the pallets based on pattern matching using the captured image and the shape information in the information of the target.

[0066] In addition, the detection unit 121 determines whether the detected pallet is loaded with a load. For example, the detection unit 121 determines whether each pallet is loaded with a load based on pattern matching using the captured image and the shape information in the information of the target.

[0067] The operation control unit 122 automatically controls the traveling vehicle body 2 and the fork 3 based on the information detected by the detection unit 121. For example, the operation control unit 122 determines the pallet at the position closest to the forklift 1 among the pallets loaded with loads, and automatically controls the determined pallet as the handling target. In addition, the pallet as the handling target is not limited to the pallet at the position closest to the forklift 1, and may also be a pallet existing in a specific area.

[0068] Specifically, the motion control unit 122 determines the orientation of the pallet to be transported and controls the traveling vehicle body 2 to move to a position where the forklift 1 faces the front of the pallet. For example, when the pallet is rectangular in a top view, the motion control unit 122 determines any one of the four sides constituting the rectangular shape as the front of the pallet. Next, after moving to the front of the pallet, the motion control unit 122 determines the position of the fork insertion hole of the pallet. For example, the motion control unit 122 determines the position of the fork insertion hole based on the captured image obtained by the detection unit 121 and the shape information of the target object (pallet).

[0069] Next, the motion control unit 122 controls the lifting unit 4. After aligning the height position of the fork 3 with the determined position of the fork insertion hole, it controls the traveling vehicle body 2 to insert the fork 3 into the fork insertion hole. Then, after inserting the fork 3 into the fork insertion hole, the motion control unit 122 controls the lifting unit 4 to raise the fork 3, thereby lifting the pallet. Then, the motion control unit 122 automatically calculates the route (e.g., the shortest distance route) to the target position where the pallet is to be placed. Then, the motion control unit 122 controls the traveling vehicle body 2 to move along the route to the target position. After reaching the target position, it controls the lifting unit 4 to place the pallet at the target position. Then, after placing the pallet, the motion control unit 122 determines the pallet to be the next transportation object and transports them in sequence.

[0070] Next, Figure 4 is used to illustrate a functional configuration example of the weight detection device 20. As Figure 4 shown, the weight detection device 20 includes a communication unit 21, a control unit 22, and a storage unit 23. The control unit 22 includes a detection unit 221, a determination unit 222, an estimation unit 223, and a storage processing unit 224.

[0071] The communication unit 21 is implemented, for example, by a NIC (Network Interface Card) or the like. The communication unit 21 is connected to the network by wire or wirelessly. For example, the communication unit 21 is connected to the server device that manages the forklift 1 in a communicable manner. In addition, the communication unit 11 and the communication unit 21 may also be a single communication unit shared by the control device 10 and the weight detection device 20.

[0072] The association information 231 stored in the storage unit 23 is information generated by the storage processing unit 224 described later. Figure 5 is a diagram showing an example of the association information 231. As Figure 5 shown, the association information 231 includes "pallet ID", "category", "variety", "quantity", and "weight".

[0073] "Pallet ID" is identification information for identifying a pallet. "Category" is information indicating the type of outer packaging in the load. "Variety" is information indicating the variety of the contents. "Quantity" is information indicating the quantity of the load. "Weight" is information indicating the weight of the contents.

[0074] The control unit 22 detects the appearance information of the load loaded on the pallet inserted by the fork 3, determines the outer packaging other than the contents in the load based on the detected appearance information, and estimates the weight of the contents based on the determined outer packaging. Thus, the weight of the contents can be detected based on the weight of the outer packaging (e.g., cardboard box, etc.) that houses the contents in the load.

[0075] The detection unit 221 detects the appearance information of the load loaded on the pallet inserted by the fork 3. For example, the detection unit 221 detects the captured image captured by the camera of the condition detection sensor 5 and the shape information of the target detected by the Lidar, radar device, etc. of the condition detection sensor 5 as the appearance information.

[0076] In addition, the detection unit 221 detects (acquires) the load applied to the fork 3 when the pallet is lifted by the fork 3 from the load sensor 6. That is, the detection unit 221 detects the load of the load sensor as the total weight of the pallet and the load.

[0077] In addition, the detection unit 221 detects the weight of the pallet. For example, the detection unit 221 uses the condition detection sensor 5 such as a camera to detect the weight information recorded on the pallet, thereby detecting the weight of the pallet. The weight information is, for example, encoded information embedded with the weight information of the pallet. The encoded information is a QR code or a barcode. In addition, the weight information can be, in addition to the encoded information, information directly printed with the weight of the pallet on the pallet.

[0078] The determination unit 222 determines the outer packaging other than the contents in the load based on the appearance information detected by the detection unit 221. For example, the determination unit 222 determines the outer packaging based on the captured image and the shape information of the target. The outer packaging is, for example, a member that houses the contents, such as a cardboard box, wrapping paper, packaging material, box body, housing, etc. In addition, the determination unit 222 determines the category (raw material of the cardboard box, etc.) of the determined outer packaging.

[0079] In addition, the determination unit 222 determines the load information related to the load based on the appearance information. Regarding the load information, for example, the variety of the contents and the quantity of the load (the number of cardboard boxes, etc.) are determined. For example, the determination unit 222 determines the load information based on the captured image and the shape information of the target. The variety of the load can be determined, for example, based on the information printed on the cardboard box as the outer packaging.

[0080] The estimation unit 223 estimates the weight of the contents based on the determined outer packaging. First, the estimation unit 223 estimates the weight of the determined outer packaging. For example, the estimation unit 223 estimates the weight of the outer packaging based on the size, raw materials, etc. of the outer packaging. Then, the estimation unit 223 estimates the weight of the contents based on the estimated weight of the outer packaging and the load detected by the load sensor 6. More specifically, the estimation unit 223 estimates the weight of the contents by subtracting the weight of the pallet and the weight of the outer packaging from the above-mentioned load. That is, the estimation unit 223 estimates the weight of the contents as the weight obtained by subtracting the weight of the pallet and the weight of the outer packaging from the load (the total weight of the pallet and the loaded goods).

[0081] The storage processing unit 224 associates the load information determined by the determination unit 222 with the weight of the contents estimated by the estimation unit 223 and stores it as the association information 231 in the storage unit 23. In addition, for the storage processing unit 224, the association object of the load information is not limited to the weight of the contents, and may also be the weight of the load including the weight of the outer packaging, and further, may also be the total weight of the pallet including the weight of the pallet. Thus, the operation of the operator to record the weight of the load (contents) on paper for each pallet can be eliminated.

[0082] Next, use Figure 6 to illustrate the processing procedure of the processing executed by the control device 10 according to the first embodiment. Figure 6 It is a flowchart showing the processing procedure of the processing executed by the control device 10 according to the first embodiment.

[0083] The control unit 12 uses the condition detection sensor 5 to detect the pallet (step S101). Then, the control unit 12 controls the traveling vehicle body 2 to move it near the pallet (step S102).

[0084] Next, the control unit 12 detects the position of the fork insertion hole of the pallet (step S103), and controls the lifting unit 4 to move the fork 3 to the height position of the fork insertion hole (step S104).

[0085] Next, the control unit 12 moves the traveling vehicle body 2 to insert the fork 3 into the pallet (step S105), and controls the lifting unit 4 to raise the fork 3 to lift the pallet (step S106).

[0086] Next, the control unit 12 controls the traveling vehicle body 2 in the state where the pallet is lifted to move it to the target position (step S107), and at the target position, controls the lifting unit 4 to lower the fork 3 to place the pallet (step S108), and ends the processing.

[0087] Next, use Figure 7To illustrate the processing procedure of the weight detection device 20 according to the first embodiment. Figure 7 It is a flowchart showing the processing procedure of the weight detection device 20 according to the first embodiment.

[0088] The control unit 22 detects the appearance information of the load loaded on the tray (step S201).

[0089] Next, the control unit 22 detects the load applied to the fork 3 from the load sensor 6 in a state where the tray is lifted by the fork 3 (step S202).

[0090] Next, the control unit 22 determines the outer packaging of the load based on the appearance information (step S203), and estimates the weight of the outer packaging (step S204).

[0091] Next, the control unit 22 estimates the weight of the contents based on the load applied to the fork 3 and the weight of the outer packaging (step S205). Next, the control unit 22 determines the load information related to the load based on the appearance information (step S206).

[0092] Next, the control unit 22 stores the association information 231 associating the determined load information with the estimated weight of the contents in the storage unit 23 (step S207), and ends the processing.

[0093] Next, use Figure 8 and Figure 9 To illustrate the setting example of the condition detection sensor 5 when the tip of the fork 3 is tapered. Figure 8 and Figure 9 It is a diagram showing the setting example of the condition detection sensor 5 according to the first modification example and the second modification example. In Figure 8 shows a side view of observing the tip of the fork 3 from the side (positive Z-axis direction), and in Figure 9 shows a bottom view of observing the tip of the fork 3 from the road surface R side (negative Y-axis direction).

[0094] As Figure 8 and Figure 9As shown, the end portion of the fork 3 has an inclined surface 3b on the road surface R side (the surface on the negative Y-axis side) that becomes thinner as it approaches the end of the fork 3 (the negative X-axis direction). Specifically, the end portion of the fork 3 has an inclined surface 3b on the end side among the surfaces on the road surface R side, and a flat surface 3c on the base end side (the positive X-axis direction side). That is, in the end portion of the fork 3, a part corresponding to the inclined surface 3b has a tapered shape, and the remaining portion corresponding to the flat surface 3c has a uniform thickness (the length in the Y-axis direction). In other words, the end portion of the fork 3 has the following gradient shape: the surface on the road surface R side is thinner at the end of the fork 3 compared to the opposite side surface (the surface on the positive Y-axis side).

[0095] Moreover, the concave portion 3a is provided over the inclined surface 3b and the flat surface 3c. In addition, the concave portion 3a can also be provided only on the inclined surface 3b among the inclined surface 3b and the flat surface 3c. That is, the concave portion 3a has a shape in which at least a part of the inclined surface 3b is recessed.

[0096] Moreover, the condition detection sensor 5 is housed in the concave portion 3a at the position of the inclined surface 3b. In addition, when the concave portion 3a is provided over the inclined surface 3b and the flat surface 3c, the condition detection sensor 5 can also be housed in the concave portion 3a at the position of the flat surface 3c.

[0097] In this way, by providing the concave portion 3a on the road surface R side, the condition detection sensor 5 can be provided even if the end portion of the fork 3 has a tapered shape.

[0098] (Second Embodiment)

[0099] Refer to Figures 10 - 15 to describe the forklift 1 according to the second embodiment. Figure 10 is a schematic side view of the forklift 1 according to the second embodiment. In addition, the description of the same components as in the first embodiment is omitted.

[0100] As Figure 10 shown, the forklift 1 according to the second embodiment includes a traveling vehicle body 2, a fork 3, a lifting unit 4, a condition detection sensor 5, a load sensor 6, a control device 10, and a weight detection device 20. The configurations of the traveling vehicle body 2, the fork 3, the lifting unit 4, the condition detection sensor 5, the load sensor 6, the control device 10, and the weight detection device 20 are the same as those in the first embodiment, so the description is omitted.

[0101] Figure 11 is a diagram showing a configuration example of the window portion 7 according to the second embodiment. In Figure 11 , the cross-section taken along line III-III in Figure 10 is shown. In addition, in Figure 11 , a view of the fork 3 observed obliquely from below from the end side toward the base end side is shown.

[0102] As Figure 11 shown, a window portion 7 is formed at the end portion of the fork 3. The window portion 7 is formed to open in a manner communicating with the inside of the recess 3a at the end portion of the fork 3. The window portion 7 is formed at least on either the upper side or the side of the condition detection sensor 5 disposed inside the recess 3a. In the second embodiment, the window portion 7 is formed on the upper side of the condition detection sensor 5 and on the respective sides of the left and right (the positive and negative directions of the Z axis).

[0103] According to this configuration, the condition detection sensor 5 can be used to detect the conditions above and on the side of the fork 3 via the window portion 7 formed at the end portion of the fork 3. Thereby, the condition at the end of the fork can be grasped more accurately. In addition, by enabling the detection of the conditions above and on the side of the fork 3, accurate insertion of the fork 3 into the fork insertion hole 8 of the tray P can be achieved. In addition, when the window portion is formed on the side of the condition detection sensor 5, adjustment in the width direction of the fork 3 becomes easy. In addition, since the window portion 7 serves as a weight reduction portion at the end portion of the fork 3, weight reduction of the fork 3 can also be achieved.

[0104] In addition, the window portion 7 is not limited to the configuration of being formed on the upper side and the left and right sides of the condition detection sensor 5. For example, it may be formed only on the upper side of the condition detection sensor 5, or for example, only on the outer side among the left and right sides of the condition detection sensor 5.

[0105] In addition, the window portion 7 is formed as a rectangular hole. In addition, the window portion 7 is not limited to a rectangular hole. For example, it may be a circular hole or an elliptical hole.

[0106] In addition, the window portion 7 is covered with a glass member 7a. The glass member 7a is, for example, a member made of transparent tempered glass. When the condition detection sensor 5 is a camera, the glass member 7a is preferably colorless and transparent. In addition, when the condition detection sensor 5 is a Lidar or a radar device, the glass member 7a does not necessarily have to be transparent.

[0107] The glass member 7a is provided corresponding to the opening (inside) shape of the window portion 7. In other words, the glass member 7a is provided to fill the window portion 7. Therefore, the glass member 7a is substantially coplanar with the outer peripheral surface of the fork 3.

[0108] According to this configuration, for example, even when the fork 3 is moved, breakage of the condition detection sensor 5 due to external forces such as contact between the fork 3 and the tray P can be suppressed, and in addition, accumulation of dust and the like that have invaded from the window portion 7 on the condition detection sensor 5 can be suppressed. Thereby, the durability of the condition detection sensor 5 can be improved.

[0109] In addition, since the glass member 7a is a member made of tempered glass, the glass member 7a can ensure appropriate strength.

[0110] In addition, the glass member 7a can be formed, for example, to be thinner than the thickness of the window portion 7 inside the window portion 7. Additionally, the glass member 7a can be set to be thinner than the thickness of the window portion 7 and be substantially coplanar with the outer peripheral surface of the fork 3 at the outermost side of the window portion 7. In this case, in the case of the window portion 71 above the condition detection sensor 5, the glass member 7a is substantially coplanar with the upper surface of the fork 3, and in the case of the window portions 72 and 73 on the left and right sides of the condition detection sensor 5, the glass member 7a is substantially coplanar with the left and right side surfaces of the fork 3, respectively.

[0111] Similarly in this case, since the glass member 7a is a member made of tempered glass, even if the glass member 7a is formed to be thinner than the thickness of the window portion 7, the glass member 7a can ensure appropriate strength.

[0112] Further, in the case where the fork 3 is constituted by a pair of left and right ones, for example, the window portion 7 and the glass member 7a are provided on the left and right forks 3L and 3R, respectively.

[0113] Next, an example of the condition detection of the fork end according to the second embodiment will be described using Figure 12 and 13. Figure 12 and 13 are diagrams showing an example of the condition detection of the fork end according to the second embodiment. In Figure 12 , a schematic cross-section of the tray P and the fork 3 inserted into the fork insertion hole 8 of the tray P as viewed from the side (viewed from the positive Z-axis direction) is shown. In Figure 13 , a schematic cross-section of the tray P and the fork 3 inserted into the fork insertion hole 8 of the tray P as viewed from above (viewed from the positive Y-axis direction) is shown.

[0114] As shown in Figure 12 and 13, in the forklift 1 (refer to Figure 10 ), the fork 3 is inserted into the fork insertion hole 8 of the tray P, and the condition detection sensor 5 is used to detect whether the end portion has reached the exit on the side opposite to the entrance (insertion port) of the fork 3 (that is, whether the end portion of the fork 3 has protruded from the fork insertion hole 8).

[0115] In this case, as shown in Figure 12 , the condition detection sensor 5 detects the condition above the fork 3, so that it can be detected whether the end portion of the fork 3 has protruded from the exit of the fork insertion hole 8. Additionally, in this case, as shown in Figure 13 , the condition detection sensor 5 detects the condition on the left and right sides of the fork 3, so that it can be detected whether the end portion of the fork 3 has protruded from the exit of the fork insertion hole 8.

[0116] Next, an example of the adjustment of the width D (left and right width) of the fork 3 according to the second embodiment will be described using Figure 14 .Figure 14 This is a diagram showing an example of adjusting the width D of the fork 3 according to the first embodiment. In Figure 14 , a diagram of the fork 3 as viewed from the distal end side toward the proximal end side (viewed from the negative X-axis direction) is shown.

[0117] As Figure 14 shown, in the forklift 1 (refer to Figure 10 ), window portions 7 (72, 73) are formed on the opposing sides (the inner sides of the two forks, i.e., the inner sides of the forks 3L and 3R) of a plurality of forks 3, for example, a pair of left and right forks 3 (3L, 3R). Thus, the condition detection sensor 5 detects the left and right intervals between the two forks, i.e., forks 3L and 3R, and adjusts the width D between forks 3L and 3R.

[0118] In this case, the left and right intervals between the two forks, i.e., forks 3L and 3R, can be detected using the condition detection sensors 5 of the respective two forks, i.e., forks 3L and 3R, or the left and right intervals between the two forks, i.e., forks 3L and 3R, can be detected using the condition detection sensor 5 of any one of the two forks, i.e., forks 3L and 3R.

[0119] According to this configuration, adjustment in the width D direction between the two forks, i.e., forks 3L and 3R, can be performed, and thus more accurate insertion of the fork 3 into the fork insertion hole 8 can be achieved.

[0120] Next, the forklift according to the modified example of the second embodiment will be described using Figure 15 . Figure 15 This is a diagram showing a configuration example of the window portion 7 according to the modified example of the second embodiment. In Figure 15 , similar to Figure 11 , a cross-section taken along line III-III in Figure 10 is shown. In Figure 15 , a diagram of the fork 3 as viewed obliquely from below from the distal end side toward the proximal end side is shown.

[0121] In addition, in the modified example of the second embodiment described below, the member covering the window portion 7 (the mesh member 7b described later) is different from the above-described second embodiment. Therefore, in the following description, the same reference numerals are given to the same or equivalent parts as those in the second embodiment, and sometimes the description of the same or equivalent parts as those in the second embodiment is omitted.

[0122] As Figure 15 shown, also in the second embodiment, a window portion 7 is formed at the distal end portion of the fork 3. The window portion 7 is formed to open in a manner communicating with the inside of the recess 3a at the distal end portion of the fork 3. The window portion 7 is formed at least on either the upper side or the side of the condition detection sensor 5 disposed inside the recess 3a. In the modified example of the second embodiment, the window portion 7 is formed on the upper side and the respective side portions on the left and right (the positive and negative directions of the Z-axis) of the condition detection sensor 5.

[0123] According to this configuration, it is possible to use the condition detection sensor 5 to detect the conditions above and on the sides of the fork 3 through the window portion 7 formed at the end portion of the fork 3. Thus, it is possible to more accurately grasp the condition of the fork tip. In addition, by enabling the detection of the conditions above and on the sides of the fork 3, accurate insertion of the fork 3 into the fork insertion hole 8 (refer to Figure 12 and 13) of the tray P (refer to Figure 12 and 13) can be achieved. In addition, when a window portion is formed on the side of the condition detection sensor 5, adjustment in the width D (refer to Figure 14 ) direction of the fork 3 becomes easy. In addition, since the window portion 7 serves as a weight-reducing portion at the end portion of the fork 3, weight reduction of the fork 3 can also be achieved.

[0124] In addition, the window portion 7 is not limited to the configuration of being formed above and on the left and right sides of the condition detection sensor 5. For example, it may be formed only above the condition detection sensor 5, or for example, only on the outer side among the left and right sides of the condition detection sensor 5.

[0125] In addition, the window portion 7 is formed as a rectangular hole. In addition, the window portion 7 is not limited to a rectangular hole, and for example, it may be a circular hole or an elliptical hole.

[0126] In addition, the window portion 7 is covered with a mesh member 7b having a mesh. The mesh member 7b is, for example, made of metal. In addition, the mesh member 7b may be made of a hard raw material other than metal (for example, hard synthetic resin). In this case, engineering plastics or the like can be used as the mesh member 7b.

[0127] The mesh member 7b is arranged to correspond to the opening shape of the window portion 7. The mesh member 7b is substantially coplanar with the outer peripheral surface of the fork 3.

[0128] According to this configuration, for example, even when the fork 3 is operated, breakage of the condition detection sensor 5 due to external forces such as contact between the fork 3 and the tray P can be suppressed. Thus, the durability of the condition detection sensor 5 can be improved.

[0129] In addition, since the mesh member 7b is a metal member, the mesh member 7b can ensure appropriate strength.

[0130] In addition, when the fork 3 is composed of, for example, a pair of left and right parts, the window portion 7 and the mesh member 7b are respectively provided on the left and right forks 3L and 3R.

[0131] In addition, in the above-described second embodiment and the modified example of the second embodiment, the glass member 7a or the mesh member 7b is configured to be provided as a member for covering the window portion 7. However, the member for covering the window portion 7 is not limited thereto. For example, it may also be a member made of an acrylic resin (acrylic member). Even when using this acrylic member, it is possible to suppress breakage of the condition detection sensor 5 and the accumulation of dust and the like on the condition detection sensor 5, and the durability of the condition detection sensor 5 can be improved.

[0132] In addition, when the condition detection sensor 5 is a camera, the acrylic member needs to be transparent. However, when the condition detection sensor 5 is a Lidar or a radar device, the acrylic member does not necessarily have to be transparent.

[0133] In addition, when the condition detection sensor 5 is a Lidar or a radar device, as a member for covering the window portion 7, for example, a cloth member (cloth member) that transmits light and radio waves can be used. In addition, the cloth member in this case is, for example, a reinforced cloth with a resin coating applied thereto. Therefore, the cloth member can ensure appropriate strength. Even when using this cloth member, it is possible to suppress breakage of the condition detection sensor 5 and the accumulation of dust and the like on the condition detection sensor 5, and the durability of the condition detection sensor 5 can be improved.

[0134] Furthermore, as a member for covering the window portion 7, a shutter-like member (shutter member) formed by arranging a plurality of plates in parallel at a given interval can also be used. In addition, since a gap is formed in the shutter member, even when the condition detection sensor 5 is a camera, it is possible to detect the conditions above and to the side of the fork 3 from the gap. Even when using this shutter member, it is possible to suppress breakage of the condition detection sensor 5 and the accumulation of dust and the like on the condition detection sensor 5, and the durability of the condition detection sensor 5 can be improved.

[0135] In addition, when using the shutter member, if the shutter member is configured to be able to control the opening and closing of the window portion 7, for example, the shutter member can also be controlled to open the window portion 7 when the fork 3 is inserted into the fork insertion hole 8 of the tray P, and to close the window portion 7 in other cases.

[0136] (Third Embodiment)

[0137] Refer to Figures 16 - 20 to describe the forklift 1 according to the third embodiment. Figure 16 is a diagram showing the control system of the forklift 1 according to the third embodiment. In addition, the description of the same configurations as those in the above-described embodiments is omitted.

[0138] As Figure 16As shown, the control system 100 of the forklift 1 includes the forklift 1, the control device 10, the pallet P, and the fork insertion hole detection unit 8A. The forklift 1 includes a traveling vehicle body 2, a fork 3, a lifting unit 4, a condition detection sensor 5, a load sensor 6, a control device 10, and a weight detection device 20. The traveling vehicle body 2, the fork 3, the lifting unit 4, the condition detection sensor 5, the load sensor 6, the control device 10, and the weight detection device 20 have the same configurations as those in the above-described embodiment, and thus the description thereof is omitted.

[0139] The fork insertion hole detection unit 8A detects the fork insertion hole 8. The fork insertion hole detection unit 8A includes a fork-side communication unit 81 and a pallet-side communication unit 82.

[0140] Next, Figure 17 and Figure 18 will be used to describe the fork insertion hole detection unit 8A according to the third embodiment. Figure 17 and Figure 18 are diagrams showing the fork insertion hole detection unit 8A according to the third embodiment. In Figure 17 , a diagram of the fork insertion hole 8 viewed obliquely from below is shown. In Figure 18 , an example of a block diagram showing a control system for fork insertion hole detection is shown.

[0141] As Figure 17 shown, the insertion port 8a, which is the entrance of the fork 3 in the fork insertion hole 8 of the pallet P, has, for example, a horizontally long rectangular shape with its long side extending in the left-right direction (Z-axis direction).

[0142] The fork 3 is provided with a fork-side communication unit 81 near the end portion of the fork 3. The pallet P is provided with a pallet-side communication unit 82 near the insertion port 8a in the fork insertion hole 8 of the pallet P. The fork-side communication unit 81 and the pallet-side communication unit 82 can communicate with each other wirelessly. The fork-side communication unit 81 and the pallet-side communication unit 82 perform short-range communication such as infrared communication, for example.

[0143] The fork-side communication unit 81 and the pallet-side communication unit 82 form a part of the fork insertion hole detection unit 8A.

[0144] As Figure 18 shown, the fork insertion hole detection unit 8A includes the fork-side communication unit 81, the pallet-side communication unit 82, the condition detection sensor 5, and the control unit 12 of the control device 10. In the fork insertion hole detection unit 8A, when the fork 3 approaches the fork insertion hole 8 of the pallet P to a distance at which communication can be established between the fork-side communication unit 81 and the pallet-side communication unit 82, communication starts between the fork-side communication unit 81 and the pallet-side communication unit 82.

[0145] In the fork insertion hole detection unit 8A, the fork-side communication unit 81 and the pallet-side communication unit 82 communicate, so that in the control unit 12, the position of the fork insertion hole 8 is detected based on the detection result of the condition detection sensor 5. In the fork insertion hole detection unit 8A, for example, communication is performed until the fork 3 becomes in a posture facing the fork insertion hole 8. If the fork 3 becomes in a posture facing the fork insertion hole 8, the position of the fork insertion hole 8 is detected by using the condition detection sensor 5. Then, the control device 10 automatically controls the traveling vehicle body 2 and the fork 3 based on the detection of the fork insertion hole 8 by the fork insertion hole detection unit 8A.

[0146] According to this configuration, the fork insertion hole 8 is detected by the fork insertion hole detection unit 8A, so that it is easier for the fork 3 to find the fork insertion hole 8, and the insertion of the fork 3 into the fork insertion hole 8 can be performed more accurately and easily.

[0147] In addition, the detection of the fork insertion hole 8 can be achieved through the communication between the fork-side communication unit 81 and the pallet-side communication unit 82.

[0148] Next, Figure 19 will be used to describe the control system 200 of the forklift related to the modification of the third embodiment. Figure 19 FIG. is a diagram showing the fork insertion hole detection unit 8B related to Modification 1 of the third embodiment. In Figure 19 FIG., a diagram of observing the fork insertion hole 8 from obliquely below is shown.

[0149] As Figure 19 shown, the pallet P has a mark 83 applied to the outer peripheral portion of the insertion opening 8a of the fork 3 in the fork insertion hole 8. The mark 83 is applied to the four corners of the horizontally long rectangular insertion opening 8a. The mark 83 shows the four corners of the insertion opening 8a, thereby making the shape of the insertion opening 8a clear.

[0150] The marks 83 at the four corners of the insertion opening 8a form a part of the fork insertion hole detection unit 8B.

[0151] In the fork insertion hole detection unit 8B, since the pallet P has the mark 83 applied to the insertion opening 8a of the fork insertion hole 8, the position of the fork insertion hole 8 is detected in the control unit 12 based on the detection result of the condition detection sensor 5 ( Figure 6 the process of step S106 in FIG.). In the fork insertion hole detection unit 8B, the position of the fork insertion hole 8 is detected based on the captured image of the condition detection sensor 5 such as a camera. Then, the control device 10 automatically controls the traveling vehicle body 2 and the fork 3 based on the detection of the fork insertion hole 8 by the fork insertion hole detection unit 8B.

[0152] According to this configuration, it is easy for the condition detection sensor 5 such as a camera to recognize the insertion opening 8a from the mark 83 on the outer peripheral portion of the insertion opening 8a, so that the fork insertion hole 8 can be detected more accurately and easily.

[0153] Next, use Figure 20 to illustrate the forklift control system 300 related to the modification of the third embodiment. Figure 20 is a diagram showing the fork insertion hole detection unit 8C related to Modification 2 of the third embodiment. In Figure 20 it shows a view of the fork insertion hole 8 observed obliquely from below.

[0154] As Figure 20 shown, the pallet P has a light-emitting portion 84 that emits light on the outer peripheral portion of the insertion port 8a of the fork 3 provided in the fork insertion hole 8. The light-emitting portion 84 is provided at the four corners of the horizontally long rectangular insertion port 8a. The light-emitting portion 84 is, for example, an LED (Light-Emitting Diode). The light-emitting portion 84 emits light at the four corners of the insertion port 8a, thereby making the shape of the insertion port 8a clear.

[0155] The light-emitting portions 84 at the four corners of the insertion port 8a form a part of the fork insertion hole detection unit 8C.

[0156] In the fork insertion hole detection unit 8C, since the pallet P has the light-emitting portion 84 provided in the insertion port 8a of the fork insertion hole 8, the position of the fork insertion hole 8 is detected in the control unit 12 based on the detection result of the condition detection sensor 5. In the fork insertion hole detection unit 8C, the position of the fork insertion hole 8 is detected based on the captured image of the condition detection sensor 5 such as a camera. Then, the control device 10 automatically controls the traveling vehicle body 2 and the fork 3 based on the detection of the fork insertion hole 8 by the fork insertion hole detection unit 8C.

[0157] According to this configuration, the condition detection sensor 5 such as a camera can easily recognize the insertion port 8a based on the light of the light-emitting portion 84 on the outer peripheral portion of the insertion port 8a, so that the detection of the fork insertion hole 8 can be performed more accurately and easily.

[0158] (Fourth Embodiment)

[0159] Refer to Figures 21 - 24 to illustrate the forklift 1 related to the fourth embodiment. Figure 21 is a diagram showing an overview of the forklift 1 related to the fourth embodiment. In addition, the description of the same configurations as those in the above embodiments is omitted.

[0160] As Figure 21 shown, the forklift 1 related to the fourth embodiment includes a traveling vehicle body 2, a fork 3, a lifting unit 4, a condition detection sensor 5, a load sensor 6, a control device 10, and a weight detection device 20. The configurations of the traveling vehicle body 2, the fork 3, the lifting unit 4, the condition detection sensor 5, the load sensor 6, the control device 10, and the weight detection device 20 are the same as those in the first embodiment, so the description is omitted. In addition, inFigure 21 shows a state where the pallet P is loaded with the load L.

[0161] Figure 22 is a diagram showing an example of the condition detection of the tip of the fork 3 according to the fourth embodiment. In Figure 22 shows a schematic cross-sectional view of the pallet P and the fork 3 inserted into the fork insertion hole 8 of the pallet P as viewed from the side (positive Z-axis direction).

[0162] As Figure 22 shown, when the fork 3 is inserted into the fork insertion hole 8 of the pallet P, the control device 10 detects that the tip of the fork 3 has been inserted into the fork insertion hole 8 based on the sensing result of the condition detection sensor 5.

[0163] In Figure 22 the example, the condition detection sensor 5 detects the condition below the fork 3. For example, the condition detection sensor 5 is a Lidar, a radar device, etc., and detects information on the target objects around the fork 3.

[0164] In this case, when the fork 3 is inserted into the fork insertion hole 8 of the pallet P, for example, the sensing result of the condition detection sensor 5 changes from the road surface R to the pallet P. When the condition detection sensor 5 detects the pallet P, the detection unit 131 of the control device 10 determines that the tip of the fork 3 has been inserted into the fork insertion hole 8.

[0165] Alternatively, when the condition detection sensor 5 is a camera, when the area of the pallet P (hereinafter, also referred to as the pallet area) included in the captured image becomes equal to or greater than the insertion threshold, the detection unit 131 of the control unit 12 determines that the tip of the fork 3 has been inserted into the fork insertion hole 8.

[0166] The detection unit 131 determines the pallet area included in the captured image based on the color of the pallet P, for example. For example, when the ratio of the pallet area in the captured image becomes equal to or greater than the insertion threshold, the detection unit 131 determines that the tip of the fork 3 has been inserted into the fork insertion hole 8.

[0167] At this time, the detection unit 131 can also detect the edge of the pallet area. For example, based on the inclination of the edge, the detection unit 131 can determine whether the fork 3 has been inserted horizontally with respect to the long side direction of the fork insertion hole 8 of the pallet P.

[0168] When the fork 3 is not inserted horizontally with respect to the long side direction of the fork insertion hole 8, the motion control unit 122 controls the forklift 1 so that the fork 3 is inserted horizontally with respect to the long side direction of the fork insertion hole 8. Thereby, the forklift 1 can lift the pallet P more safely.

[0169] The detection unit 131 that has detected that the tip of the fork 3 has been inserted into the fork insertion hole 8 then determines whether the tip has protruded (projected) from the fork insertion hole 8.

[0170] Figure 23 It is a diagram showing another example of the condition detection of the tip of the fork 3 related to the fourth embodiment. In Figure 23 , a schematic cross-sectional view is shown of the pallet P and the fork 3 inserted into the fork insertion hole 8 of the pallet P as viewed from the side (positive Z-axis direction).

[0171] As Figure 23 shown, when the fork 3 extends from the fork insertion hole 8 of the pallet P, the control device 10 detects the situation where the tip of the fork 3 has extended from the fork insertion hole 8 based on the sensing result of the condition detection sensor 5.

[0172] For example, the condition detection sensor 5 is a Lidar, a radar device, etc., and detects information on an object below the fork 3. In this case, when the fork 3 extends from the fork insertion hole 8 of the pallet P, for example, the sensing result of the condition detection sensor 5 changes from the pallet P to the road surface R. When the condition detection sensor 5 detects the road surface R, the detection unit 131 determines that the tip of the fork 3 has extended from the fork insertion hole 8.

[0173] Alternatively, when the condition detection sensor 5 is a camera, when the area of the pallet P included in the captured image (hereinafter, also referred to as the pallet area) becomes below the protrusion threshold, the detection unit 131 determines that the tip of the fork 3 has extended from the fork insertion hole 8.

[0174] The detection unit 131 determines the pallet area included in the captured image based on the color of the pallet P, for example. For example, when the ratio of the pallet area in the captured image becomes below the protrusion threshold, the detection unit 131 determines that the tip of the fork 3 has extended from the fork insertion hole 8.

[0175] At this time, the detection unit 131 can also detect the edge of the pallet area. For example, the detection unit 131 can determine whether the fork 3 has been inserted horizontally with respect to the long side direction of the fork insertion hole 8 of the pallet P according to the inclination of the edge.

[0176] When the fork 3 is not inserted horizontally with respect to the long side direction of the fork insertion hole 8, the motion control unit 122 controls the forklift 1 so that the fork 3 is inserted horizontally with respect to the long side direction of the fork insertion hole 8. Thereby, the forklift 1 can lift the pallet P more safely.

[0177] Here, in order for the forklift 1 to safely carry the load L, it is important to lift the pallet P more stably. Even if the end portion of the fork 3 does not protrude from the fork insertion hole 8 of the pallet P, the forklift 1 can still lift the pallet P. However, when the end portion of the fork 3 protrudes from the fork insertion hole 8 of the pallet P, the forklift 1 can lift the pallet P more safely compared to when it does not protrude. This is because when the end portion of the fork 3 protrudes from the fork insertion hole 8 of the pallet P, the contact portion between the fork 3 and the pallet P becomes larger, and the fork 3 can support the pallet P more stably. Therefore, by lifting the pallet P with the fork 3 in a state where the end portion of the fork 3 has protruded from the fork insertion hole 8 of the pallet P, the forklift 1 can carry the load L more safely.

[0178] In addition, the determination performed by the detection unit 131 is not limited to the above examples. For example, the detection unit 131 can also determine whether the end portion of the fork 3 has been inserted into the fork insertion hole 8 or the end portion of the fork 3 has protruded from the fork insertion hole 8 based on the difference in brightness around the end portion of the fork 3.

[0179] For example, in the case where the captured image is dark, more specifically, when the average brightness value of the captured image is less than the brightness threshold, the detection unit 131 determines that the end portion of the fork 3 has been inserted into the fork insertion hole 8.

[0180] For example, in the case where the captured image is bright, more specifically, when the average brightness value of the captured image is equal to or greater than the brightness threshold, the detection unit 131 determines that the end portion of the fork 3 has protruded from the fork insertion hole 8.

[0181] In addition, here, the detection unit 131 uses the captured image of the camera to determine whether the periphery of the end portion of the fork 3 is bright. However, the method for the detection unit 131 to determine brightness is not limited to this. For example, when the condition detection sensor 5 is a brightness sensor, the detection unit 131 determines whether the periphery of the end portion of the fork 3 is bright based on the brightness detected by the brightness sensor.

[0182] For example, in the case where the periphery of the end portion of the fork 3 is dark, more specifically, when the detection result (brightness value) of the brightness sensor is less than the threshold, the detection unit 131 determines that the end portion of the fork 3 has been inserted into the fork insertion hole 8.

[0183] For example, in the case where the periphery of the end portion of the fork 3 is bright, more specifically, when the detection result (brightness value) of the brightness sensor is equal to or greater than the threshold, the detection unit 131 determines that the end portion of the fork 3 has protruded from the fork insertion hole 8.

[0184] Figure 24 It is a flowchart showing an example of the process of the processing executed by the control device 10 according to the fourth embodiment.

[0185] The control unit 12 of the control device 10 uses the condition detection sensor 5 to detect the pallet P (step S301). Next, the control unit 12 controls the traveling vehicle body 2 to move it near the pallet P (step S302).

[0186] Next, the control unit 12 detects the position of the fork insertion hole 8 of the pallet P (step S303), and controls the lifting unit 4 to move the fork 3 to the height position of the fork insertion hole 8 (step S304).

[0187] The control unit 12 moves the traveling vehicle body 2 to insert the fork 3 into the pallet P (step S305). The control unit 12 determines whether the end of the fork 3 has protruded from the pallet P (step S306).

[0188] When the end of the fork 3 has not protruded from the pallet P (step S306; NO), the control unit 12 returns to step S305 to insert the fork 3 into the pallet P. On the other hand, when the end of the fork 3 has protruded from the pallet P (step S306; YES), the control unit 12 controls the lifting unit 4 to raise the fork 3 to lift the pallet P (step S307).

[0189] The control unit 12 controls the traveling vehicle body 2 while carrying the pallet P to move it to the target position (step S308). The control unit 12 controls the lifting unit 4 at the target position to lower the fork 3 to place the pallet P (step S309), and ends the process.

[0190] (Fifth Embodiment)

[0191] Refer to Figures 25 - 27 to describe the forklift 1 according to the fifth embodiment. Figure 25 is a schematic side view of the forklift according to the fifth embodiment. Figure 26 is a schematic top view of the forklift 1 according to the fifth embodiment. In addition, descriptions of the same configurations as those in the above embodiments are omitted.

[0192] The forklift 1 includes a traveling vehicle body 2, a fork 3, a lifting unit 4, a first detection sensor 9, a load sensor 6, a second detection sensor 5, a control device 10, and a weight detection device 20. The configurations of the traveling vehicle body 2, the fork 3, the lifting unit 4, the load sensor 6, the control device 10, and the weight detection device 20 are the same as those in the above embodiments, and thus the descriptions are omitted.

[0193] The first detection sensor 9 is disposed on the traveling vehicle body 2. The first detection sensor 9 acquires information related to the conditions around the traveling vehicle body 2. The first detection sensor 9 acquires at least information related to the conditions on the front side (negative X-axis direction) of the traveling vehicle body 2. The first detection sensor 9 is arranged to acquire, for example, information related to the conditions on the front side of the traveling vehicle body 2 from between a pair of support portions 4a. The first detection sensor 9 can also acquire information related to the conditions on the side (Z-axis) side of the traveling vehicle body 2.

[0194] The first detection sensor 9 is, for example, a camera. The camera is mounted on the traveling vehicle body 2 so as to be able to photograph the vicinity in front of the traveling vehicle body 2. The camera includes, for example, an imaging element such as a CCD (Charge Coupled Device) or a CMOS (Complementary Metal Oxide Semiconductor), and a lens. The first detection sensor 9 can include at least one of a solid-state LiDAR (light detection and ranging), a multi-color laser coaxial displacement meter, or various other sensors. The first detection sensor 9 can include a MoPU (Motion Processing Unit). The MoPU is a unit that detects the motion of a high-resolution camera. The MoPU outputs, for example, motion information indicating the motion of an object photographed at a frame rate of 1000 frames per second or more, at a frame rate of 1000 frames per second or more. Further, vector information of the motion of a point indicating the existence position of the object along a given coordinate axis is output as the motion information. That is, the motion information output from the MoPU does not include information required to identify what the photographed object is (for example, a person or an obstacle), but only includes information indicating the motion (moving direction and moving speed) of the center point (or center of gravity point) of the object on the coordinate axes (x-axis, y-axis, z-axis).

[0195] The second detection sensor 5 (condition detection sensor 5) is disposed on the fork 3. The second detection sensor 5 is disposed in front compared with the first detection sensor 9. The second detection sensor 5 acquires information related to the conditions around the traveling vehicle body 2. The second detection sensor 5 acquires at least information related to the front side of the fork 3. The second detection sensor 5 can also acquire information related to at least one of the side and the lower side of the fork 3.

[0196] The second detection sensor 5 is, for example, a camera. Similar to the first detection sensor 9, the second detection sensor 5 can be a solid-state LiDAR or the like. The second detection sensor 5 can be a sensor with lower detection accuracy compared to the first detection sensor 9. For example, the second detection sensor 5 can be a camera with a smaller number of pixels compared to the first detection sensor 9.

[0197] Next, a flowchart of Figure 27 is referred to for explaining the detection process according to the fifth embodiment. Figure 27 is a flowchart for explaining the detection process according to the fifth embodiment. The detection process is a process of switching the detection sensors used in the travel control of the traveling vehicle body 2.

[0198] The control device 10 uses the first detection sensor 9 to determine whether the situation in front of the traveling vehicle body 2 can be detected (step S400). For example, the control device 10 determines whether the distance of the target object detected by the first detection sensor 9 is equal to or less than a preset given distance. When the distance of the target object detected by the first detection sensor 9 is equal to or less than the preset given distance, the control device 10 determines that the situation in front of the traveling vehicle body 2 cannot be detected by the first detection sensor 9. When the distance of the target object detected by the first detection sensor 9 is longer than the preset given distance, the control device 10 determines that the situation in front of the traveling vehicle body 2 can be detected by the first detection sensor 9.

[0199] When the control device 10 can detect the situation in front of the traveling vehicle body 2 using the first detection sensor 9 (step S400: Yes), it detects the situation around the front of the traveling vehicle body 2 based on the information detected by the first detection sensor 9 (step S401).

[0200] When the control device 10 cannot detect the situation in front of the traveling vehicle body 2 using the first detection sensor 9 (step S400: No), it detects the situation around the front of the traveling vehicle body 2 based on the information detected by the second detection sensor 5 (step S402).

[0201] In addition, when the control device 10 detects the situation around the front of the traveling vehicle body 2 based on the information detected by the second detection sensor 5, it can correct the information detected by the second detection sensor 5 according to the height of the fork 3. The height of the fork 3 is detected by the second detection sensor 5, for example. The height of the fork 3 can be detected based on the current lifting position of the fork 3, for example, the value of the control signal for controlling the fork 3 in the lifting unit 4. Additionally, a sensor for detecting the height of the fork 3 can be provided.

[0202] For example, the control device 10 corrects the information detected by the second detection sensor 5 based on the installation angle of the second detection sensor 5 relative to the fork 3 and the height of the fork 3, and calculates the distance from the end of the fork 3 to the target object. The installation angle is a preset angle. For example, when the second detection sensor 5 (for example, the optical axis of the lens of the camera) is installed obliquely downward, the control device 10 calculates the distance between the end of the fork 3 and the target object in the horizontal direction based on the installation angle (for example, the optical axis of the lens of the camera relative to the fork 3), the distance to the target object calculated using the information of the second detection sensor 5, and the height of the fork 3.

[0203] Thereby, the forklift 1 can further suppress contact between the forklift 1 and the target object.

[0204] (Sixth Embodiment)

[0205] Refer to Figures 28 - 29 to describe the forklift 1 according to the sixth embodiment. Figure 28 It is a diagram showing a state in which the fork according to the sixth embodiment is inclined upward. In addition, descriptions of the same configurations as those in the above embodiments are omitted.

[0206] As Figure 28 shown, the lifting unit 4 changes the inclination state of the fork 3. The lifting unit 4 rotates the fork 3 around the base end side of the fork 3 to change the inclination state of the fork 3. The inclination state of the fork 3 includes the inclination angle T of the fork 3. For example, as Figure 28 shown, the inclination angle T of the fork 3 is the inclination angle in the up and down directions with the horizontal direction as the reference angle.

[0207] In addition, the lifting unit 4 may also change the inclination state of the fork 3 integrally with a part of the lifting unit 4. For example, the lifting unit 4 includes a fixing part and an inclination part. The inclination part is integrated with the fork 3 and is configured to rotate relative to the fixing part. The inclination angle of the fork 3 may be the inclination angle relative to the fixing part.

[0208] The detection unit 121 detects the inclination of the fork 3. The detection unit 121 detects the inclination of the fork 3 based on the captured image and the information of the target object. For example, the detection unit 121 detects the inclination of the fork 3 based on the change in the position of the target object in the captured image. The detection unit 121 calculates the inclination angle T of the fork 3 based on, for example, the distance to the target object and the change in the up and down direction position of the target object in the captured image. For example, the detection unit 121 detects the inclination of the fork 3 based on the captured images before and after the operation control unit 122 outputs a signal for inclining the fork 3. The detection unit 121 uses the captured image before the operation control unit 122 outputs a signal for inclining the fork 3 and the captured image after the operation control unit 122 outputs a signal for inclining the fork 3 to detect the inclination of the fork 3.

[0209] When the detection unit 121 has a load placed on the fork 3, it determines whether the inclination of the fork 3 has reached a given inclination state.

[0210] The given inclination state is a pre-set state. The given inclination state is a state where the distal end portion of the fork 3 is located above the proximal end portion of the fork 3. When the forklift 1 is carrying a load, it inclines the fork 3 so that the pallet and the load do not fall from the fork 3 and the distal end portion of the fork 3 is located above the proximal end portion of the fork 3. The given inclination state is a state where the fork 3 is inclined so that the pallet does not fall from the fork 3.

[0211] When the inclination angle T of the fork 3 is equal to or greater than a given angle, the detection unit 121 determines that the inclination of the fork 3 is in the given inclination state. When the inclination angle T of the fork 3 is less than the given angle, the detection unit 121 determines that the inclination of the fork 3 is not in the given inclination state.

[0212] After lifting the pallet, the motion control unit 122 controls the lifting unit 4 to make the inclination of the fork 3 reach the given inclination state. The motion control unit 122 outputs a signal for controlling the lifting unit 4 to the lifting unit 4 so that the fork 3 reaches the given inclination state.

[0213] When the inclination of the fork 3 reaches the given inclination state, the motion control unit 122 automatically calculates the route (e.g., the shortest distance route) to the target position where the pallet is to be placed. Then, the motion control unit 122 controls the traveling vehicle body 2 to move along the route to the target position. After reaching the target position, it controls the lifting unit 4 to place the pallet at the target position. Then, after placing the pallet, the motion control unit 122 determines the next pallet to be carried and carries them in sequence.

[0214] When the inclination of the fork 3 does not reach the given inclination state after lifting the pallet, the motion control unit 122 prohibits the traveling of the traveling vehicle body 2. Until the inclination of the fork 3 reaches the given inclination state, the motion control unit 122 prohibits the traveling of the traveling vehicle body 2.

[0215] After the motion control unit 122 outputs a signal for controlling the lifting unit 4 to make the inclination of the fork 3 reach the given inclination state, it prohibits the traveling of the traveling vehicle body 2 until the inclination of the fork 3 reaches the given inclination state. After the motion control unit 122 outputs a signal for controlling the lifting unit 4 to make the inclination of the fork 3 reach the given inclination state, if the inclination of the fork 3 reaches the given inclination state, it starts the traveling of the traveling vehicle body 2.

[0216] The motion control unit 122 measures the time from when the signal for controlling the lifting unit 4 is output to the lifting unit 4. When the measured time reaches a given time and the inclination of the fork 3 has not yet become a given inclination state, the motion control unit 122 detects an abnormality in the lifting unit 4. When the motion control unit 122 detects an abnormality in the lifting unit 4, it notifies the occurrence of the abnormality. For example, the motion control unit 122 lights up a lamp to notify the occurrence of the abnormality. In addition, the method of notifying the occurrence of the abnormality is not limited to this. The occurrence of the abnormality can also be notified by sound. The motion control unit 122 can send a signal related to the occurrence of the abnormality to the server device that manages the forklift 1.

[0217] In addition, when the inclination of the fork 3 is no longer in the given inclination state during the movement of the traveling vehicle body 2 to the target position, the motion control unit 122 can prohibit the traveling of the traveling vehicle body 2. When the inclination of the fork 3 is no longer in the given inclination state during the movement of the traveling vehicle body 2 to the target position, for example, the motion control unit 122 decelerates the traveling vehicle body 2 and stops the traveling vehicle body 2.

[0218] Next, with reference to Figure 29 the flowchart to describe the travel permission process according to the sixth embodiment. Figure 29 It is a flowchart showing the travel permission process according to the embodiment. Here, it is assumed that the pallet to be carried is determined and the fork 3 has been inserted into the fork insertion hole of the pallet.

[0219] The control device 10 controls the lifting unit 4 (step S500). Specifically, the control device 10 uses the fork 3 to lift the pallet and controls the lifting unit 4 to make the inclination of the fork 3 a given inclination state.

[0220] The control device 10 determines whether the inclination of the fork 3 has become a given inclination state (step S501). Specifically, the control device 10 determines whether the inclination angle T of the fork 3 is equal to or greater than a given angle.

[0221] When the inclination of the fork 3 has become a given inclination state (step S501: Yes), specifically, when the inclination angle T of the fork 3 is equal to or greater than the given angle, the control device 10 moves the traveling vehicle body 2 to the target position (step S502).

[0222] When the inclination of the fork 3 has not become a given inclination state (step S501: No), specifically, when the inclination angle T of the fork 3 is less than the given angle, the control device 10 prohibits the traveling of the traveling vehicle body 2 (step S503).

[0223] The control device 10 determines whether a measurement time has elapsed from the output of the signal for controlling the lifting unit 4 to the lifting unit 4 for a given time (step S504). Specifically, the control device 10 determines whether the measurement time has elapsed for a given time from the output of the signal for controlling the lifting unit 4 to the lifting unit 4 when tilting the fork 3. When the measurement time has not elapsed for the given time (step S504: No), the control device 10 returns to step S501 and repeats the above process.

[0224] When the measurement time has elapsed for the given time (step S504: Yes), the control device 10 notifies an abnormality of the lifting unit 4 (step S505). That is, when a signal for controlling the lifting unit 4 is output to make the tilt of the fork 3 a given tilt state, but the tilt of the fork 3 does not become the given tilt state for a time longer than the given time, the control device 10 notifies an abnormality of the lifting unit 4.

[0225] The control device 10 can set a given tilt state based on at least one of the weight of the load placed on the fork 3, the height of the fork 3, and the traveling speed of the traveling vehicle body 2. Specifically, the control device 10 sets a given angle based on at least one of the weight of the load placed on the fork 3, the height of the fork 3, and the traveling speed of the traveling vehicle body 2. For example, the greater the weight of the load, the greater the given angle set by the control device 10. In addition, the higher the height of the fork 3, the greater the given angle set by the control device 10. In addition, the greater the traveling speed of the traveling vehicle body 2, the greater the given angle set by the control device 10. The traveling speed is, for example, the upper limit traveling speed of the traveling vehicle body 2. The upper limit traveling speed can be set in advance or can be set according to the type of the load, the weight of the load, and the like.

[0226] Thereby, the forklift 1 can suppress the situation where the load falls from the fork 3 during traveling.

[0227] In addition, the control device 10 can determine whether the tilt angle T of the fork 3 has become a reference angle. In other words, the control device 10 can determine whether the fork 3 is in a horizontal state. The tilt of the fork 3 can include a state where the tilt angle T of the fork 3 becomes a reference angle. When the traveling speed of the traveling vehicle body 2 is low, for example, when the traveling speed of the traveling vehicle body 2 is below a preset safe speed, the forklift 1 can travel with the tilt angle T of the fork 3 as the reference angle. The safe speed is, for example, a speed at which the pallet does not fall from the fork 3 even if the tilt angle of the fork 3 is the reference angle.

[0228] Next, Figure 30 the hardware configurations of the control device 10 and the weight detection device 20 will be described. Figure 30FIG. 0 schematically shows an example of the hardware configuration of a computer 1200 that functions as a control device 10 and / or a weight detection device 20. A program installed in the computer 1200 can cause the computer 1200 to function as one or more “units” of the device according to the present embodiment, or can cause the computer 1200 to execute operations associated with the device according to the present embodiment or the one or more “units”, and / or can cause the computer 1200 to execute a process according to the present embodiment or a stage of the process. Such a program may be executed by the CPU 1212 in order to cause the computer 1200 to execute certain operations associated with some or all of the blocks in the flowcharts and block diagrams described in this specification.

[0229] The computer 1200 according to the present embodiment includes a CPU 1212, a RAM 1214, and a graphics controller 1216, which are interconnected through a main controller 1210. The computer 1200 further includes input / output units such as a communication interface 1222, a storage device 1224, a DVD drive, and an IC card drive, which are connected to the main controller 1210 via an input / output controller 1220. The DVD drive may be a DVD-ROM drive, a DVD-RAM drive, or the like. The storage device 1224 may be a hard disk drive, a solid state drive, or the like. The computer 1200 further includes an input / output unit such as a ROM 1230 and a keyboard, which are connected to the input / output controller 1220 via an input / output chip 1240.

[0230] The CPU 1212 operates in accordance with programs stored in the ROM 1230 and the RAM 1214, and thereby controls each unit. The graphics controller 1216 acquires image data generated by the CPU 1212 in a frame buffer or the like provided in the RAM 1214 or itself, and causes the image data to be displayed on a display device 1218.

[0231] The communication interface 1222 communicates with other electronic devices through a network. The storage device 1224 stores programs and data used by the CPU 1212 in the computer 1200. The DVD drive reads programs or data from a DVD-ROM or the like and provides them to the storage device 1224. The IC card drive reads programs and data from an IC card and / or writes programs and data to the IC card.

[0232] The ROM 1230 stores therein a boot program executed by the computer 1200 at activation and / or a program dependent on the hardware of the computer 1200. The input / output chip 1240 may also connect various input / output units to the input / output controller 1220 through a USB port, a parallel port, a serial port, a keyboard port, a mouse port, or the like.

[0233] The program is provided by a computer-readable storage medium such as a DVD-ROM or an IC card. The program is read from the computer-readable storage medium and installed in the storage device 1224, the RAM 1214, or the ROM 1230, which are examples of computer-readable storage media, and is executed by the CPU 1212. The information processing described in these programs is read by the computer 1200, facilitating the cooperation between the program and the various types of hardware resources described above. The apparatus or method may be configured to implement the operation or processing of information according to the use of the computer 1200.

[0234] For example, in the case of performing communication between the computer 1200 and an external device, the CPU 1212 may execute a communication program loaded into the RAM 1214 and command the communication interface 1222 to perform communication processing based on the processing described in the communication program. Under the control of the CPU 1212, the communication interface 1222 reads the transmission data stored in the transmission buffer provided in a recording medium such as the RAM 1214, the storage device 1224, the DVD-ROM, or the IC card, transmits the read transmission data to the network, or writes the received data received from the network into the reception buffer provided on the recording medium, etc.

[0235] In addition, the CPU 1212 may read all or a required part of a file or a database stored in an external recording medium such as the storage device 1224, a DVD drive (DVD-ROM), an IC card, etc. in the RAM 1214, and perform various types of processing on the data on the RAM 1214. Then, the CPU 1212 may write the processed data back to the external recording medium.

[0236] Various types of information such as various types of programs, data, tables, and databases may be stored in the recording medium and undergo information processing. The CPU 1212 may perform various types of processing on the data read from the RAM 1214, including various types of operations, information processing, condition determination, conditional branching, unconditional branching, retrieval / replacement of information, etc. specified by the instruction sequence of the program described anywhere in the present disclosure, and write the result back to the RAM 1214. In addition, the CPU 1212 may retrieve information in files, databases, etc. in the recording medium. For example, in the case where a plurality of entries are stored in the recording medium, and each entry has an attribute value of a first attribute associated with an attribute value of a second attribute, the CPU 1212 may search the plurality of entries for an entry that matches the condition specifying the attribute value of the first attribute, and read the attribute value of the second attribute stored in the entry, thereby obtaining the attribute value of the second attribute associated with the first attribute that satisfies a predetermined condition.

[0237] The above-mentioned program or software module can be stored in a computer-readable storage medium on or near the computer 1200. Additionally, a recording medium such as a hard disk or RAM provided within a dedicated communication network or a server system connected to the Internet can be used as the computer-readable storage medium, thereby providing the program to the computer 1200 via the network.

[0238] In the flowcharts and block diagrams in this embodiment, the boxes can represent stages of a process of performing operations or "parts" of a device having the function of performing operations. Specific stages and "parts" can be implemented by dedicated circuits, programmable circuits provided together with computer-readable instructions stored on a computer-readable storage medium, and / or processors provided together with computer-readable instructions stored on a computer-readable storage medium. The dedicated circuits can include digital and / or analog hardware circuits and can include integrated circuits (ICs) and / or discrete circuits. The programmable circuits can include, for example, reconfigurable hardware circuits such as field-programmable gate arrays (FPGAs) and programmable logic arrays (PLAs), which include logical products, logical sums, exclusive ORs, negative logical products, negative logical sums, and other logical operations, flip-flops, registers, and storage elements.

[0239] The computer-readable storage medium can include any tangible device capable of storing instructions executable by an appropriate device, so that the computer-readable storage medium having instructions stored therein has a product, and the product includes instructions that can be executed to create a unit for performing the operations specified in the flowchart or block diagram. As examples of the computer-readable storage medium, it can include electronic storage media, magnetic storage media, optical storage media, electromagnetic storage media, semiconductor storage media, etc. As more specific examples of the computer-readable storage medium, it can include floppy disks (registered trademark), magnetic disks, hard disks, random access memories (RAMs), read-only memories (ROMs), erasable programmable read-only memories (EPROMs or flash memories), electrically erasable programmable read-only memories (EEPROMs), static random access memories (SRAMs), compact disc read-only memories (CD-ROMs), digital versatile discs (DVDs), Blu-ray discs (registered trademark), memory sticks, integrated circuit cards, etc.

[0240] The computer-readable instructions can include source code or object code described in any combination of one or more programming languages such as assembly instructions, instruction set architecture (ISA) instructions, machine instructions, machine-dependent instructions, microcode, firmware instructions, state-setting data, and object-oriented programming languages such as Smalltalk (registered trademark), JAVA (registered trademark), C++, etc., and conventional programming languages such as the "C" programming language or similar programming languages.

[0241] To cause a processor or programmable circuit of a general-purpose computer, a special-purpose computer, or other programmable data processing device to execute computer-readable instructions for generating units for performing the operations specified in a flowchart or block diagram, the computer-readable instructions can be provided locally or via a wide area network (WAN) such as a local area network (LAN) or the Internet to the processor or programmable circuit of the general-purpose computer, special-purpose computer, or other programmable data processing device. Examples of the processor include a computer processor, a processing unit, a microprocessor, a digital signal processor, a controller, a microcontroller, and the like.

[0242] As described above, the forklift 1 according to the embodiment includes a traveling vehicle body 2, a fork 3, and a sensor (condition detection sensor 5). The fork 3 is provided in front of the traveling vehicle body 2 and has at least a recess 3a at its end portion. The sensor is accommodated in the recess 3a and detects the condition around the end portion.

[0243] With such a configuration, the condition of the fork end can be grasped more accurately.

[0244] In addition, as described above, the weight detection device 20 according to the embodiment includes a detection unit 221, a determination unit 222, and an estimation unit 223. The detection unit 221 detects appearance information of the load loaded on the pallet inserted by the fork 3. The determination unit 222 determines the outer packaging other than the contents in the load based on the detected appearance information. The estimation unit 223 estimates the weight of the contents based on the determined outer packaging.

[0245] With such a configuration, the weight of the contents in the load can be detected.

[0246] Although the present invention has been described above using embodiments, the technical scope of the present invention is not limited to the scope described in the above embodiments. It is obvious to those skilled in the art that various changes or improvements can be made to the above embodiments. It is clear from the claims that the forms after such changes or improvements are also included in the technical scope of the present invention.

[0247] It should be noted that regarding the execution order of each process such as actions, processes, steps, and stages in the devices, systems, programs, and methods shown in the claims, specifications, and drawings, as long as it is not specifically expressed by "before", "prior to", etc., and the output of the previous process is not used in the subsequent process, it can be implemented in any order. For the action flows in the claims, specifications, and drawings, even if they are described for convenience using "first", "next", etc., it does not mean that they must be implemented in that order.

[0248] Explanation of reference numerals

[0249] 1 Forklift

[0250] 2 Traveling vehicle body

[0251] 3 Fork

[0252] 3a Concave part

[0253] 4 Lifting part

[0254] 4a Support part

[0255] 5 Condition detection sensor (second detection sensor)

[0256] 6 Load sensor

[0257] 7 Window part

[0258] 7a Glass member

[0259] 7b Mesh member

[0260] 8 Fork insertion hole

[0261] 8A - 8C Fork insertion hole detection part

[0262] 8a Insertion port

[0263] 9 First detection sensor

[0264] 10 Control device

[0265] 11, 21 Communication part

[0266] 12, 22 Control part

[0267] 13, 23 Storage part

[0268] 20 Weight detection device

[0269] 71 - 73 Window part

[0270] 81 Fork - side communication part

[0271] 82 Tray - side communication part

[0272] 83 Mark

[0273] 84 Light - emitting part

[0274] 100, 200, 300 Control system

[0275] 121 Detection part

[0276] 122 Action control part

[0277] 131, 221 Detection part

[0278] 222 Determination part

[0279] 223 Estimation part

[0280] 224 Storage Processing Unit

[0281] 231 Association Information

[0282] L Load

[0283] P Pallet

[0284] R Road Surface

Claims

1. A forklift truck, comprising: A traveling vehicle body; Forks, which are provided in front of the traveling vehicle body and have at least a concave portion at the end portion; and A sensor, which is accommodated in the concave portion and detects the condition around the end portion.

2. The forklift truck according to claim 1, wherein The concave portion has the following shape: the portion on the road surface side where the traveling vehicle body travels among the end portions is recessed.

3. The forklift truck according to claim 2, wherein The end portion has an inclined surface on the road surface side where the fork becomes thinner toward the end, The concave portion has the following shape: at least a part of the inclined surface is recessed.

4. The forklift truck according to claim 2, wherein The concave portion has a shape that is recessed from the end portion to the base end portion on the traveling vehicle body side.

5. The forklift truck according to claim 1, wherein The end of the end portion is located in front of the sensor.

6. The forklift truck according to claim 1, wherein The forklift truck further comprises a control device for automatically controlling the traveling vehicle body and the forks, The control device detects the position of the fork insertion hole in the tray based on the information detected by the sensor, and automatically inserts the fork into the fork insertion hole.

7. The forklift truck according to claim 1, wherein The forklift truck has a window portion at the end portion, and the window portion is formed by opening at least one of above and side of the sensor.

8. The forklift truck according to claim 7, wherein The window portion is covered by a glass member.

9. The forklift truck according to claim 7, wherein The window portion is covered by a grid member.

10. The forklift truck according to any one of claims 7 to 9, wherein There are multiple forks, The window portion is formed on the opposite side surfaces of the multiple forks.

11. The forklift truck according to claim 1, wherein The forklift truck has a determination unit, and the determination unit determines whether the end portion of the fork has protruded from the fork insertion hole provided in the tray based on the sensing result of the sensor.

12. The forklift truck according to claim 11, wherein The sensor has a camera, the camera photographs the condition around the end portion, and outputs an image, When the ratio of the tray area included in the image to the image is below the protrusion threshold, the determination unit determines that the end portion has protruded from the fork insertion hole.

13. The forklift truck according to claim 12, wherein When the ratio of the tray area to the image becomes below the protrusion threshold after the end portion is inserted into the fork insertion hole, the determination unit determines that the end portion has protruded from the fork insertion hole.

14. The forklift truck according to claim 11, wherein The determination unit determines whether the end portion of the fork has been inserted into the fork insertion hole.

15. The forklift truck according to claim 14, wherein The sensor has a camera, the camera photographs the condition around the end portion, and outputs an image, When the ratio of the pallet area contained in the image to the image is above the insertion threshold, the determination unit determines that the tip has been inserted into the fork insertion hole.

16. The forklift according to claim 1, wherein the forklift is provided with a control device that detects the tilt of the fork based on information detected by the sensor.

17. The forklift according to claim 16, wherein when the tilt of the fork does not reach a given tilt state while the fork is loaded with goods, the control device prohibits the running vehicle body from running.

18. The forklift according to claim 17, wherein the control device sets the given tilt state according to at least one of the weight of the goods placed on the fork, the height of the fork, and the running speed of the running vehicle body.

19. The forklift according to claim 16, wherein the control device controls the fork and the running vehicle body based on information detected by the sensor.

20. A forklift, comprising: a running vehicle body; a fork provided in front of the running vehicle body; a first detection sensor provided on the running vehicle body; a second detection sensor provided on the fork; and a control device that detects the condition in front of the running vehicle body based on information detected by at least one of the first detection sensor and the second detection sensor, the control device detects the condition in front of the running vehicle body based on information detected by the second detection sensor when it is impossible to detect the condition in front of the running vehicle body based on information detected by the first detection sensor due to the goods placed on the fork.

21. The forklift according to claim 20, wherein the control device controls the running of the running vehicle body based on the condition in front of the running vehicle body.

22. The forklift according to claim 20, wherein when the control device detects the condition in front of the running vehicle body using the second detection sensor, it corrects the information detected by the second detection sensor according to the height of the fork.

23. A control system for a forklift, comprising: a forklift having a running vehicle body, a fork, and a sensor, the fork being provided in front of the running vehicle body and having a recess at least at the tip, the sensor being accommodated in the recess and detecting the condition around the tip; a pallet having a fork insertion hole for inserting the fork; a fork insertion hole detection unit that detects the fork insertion hole; and a control device that automatically controls the running vehicle body and the fork according to the detection of the fork insertion hole by the fork insertion hole detection unit.

24. The control system for a forklift according to claim 23, wherein the fork insertion hole detection unit has a fork-side communication unit provided on the fork and a pallet-side communication unit provided on the pallet, and communication is performed between the fork-side communication unit and the pallet-side communication unit.

25. The control system for a forklift according to claim 23, wherein The fork insertion hole detection unit has a mark applied to the outer peripheral portion of the insertion opening of the fork insertion hole.

26. The control system of a forklift according to claim 23, wherein The fork insertion hole detection unit has a light-emitting unit that is provided on the outer peripheral portion of the insertion opening of the fork insertion hole and emits light.

27. A weight detection device, comprising: A detection unit that detects the appearance information of the load loaded on the pallet inserted by the fork; A determination unit that determines the outer packaging other than the contents in the load based on the detected appearance information; and An estimation unit that estimates the weight of the contents based on the determined outer packaging.

28. The weight detection device according to claim 27, wherein The detection unit uses a load sensor provided on the fork to detect the load applied to the fork, The estimation unit estimates the weight of the outer packaging and estimates the weight of the contents based on the load and the weight of the outer packaging.

29. The weight detection device according to claim 28, wherein The detection unit detects the weight of the pallet, The estimation unit estimates the weight of the contents by subtracting the weight of the pallet and the weight of the outer packaging from the load.

30. The weight detection device according to claim 29, wherein The detection unit detects the weight information recorded at the pallet using a sensor, thereby detecting the weight of the pallet.

31. The weight detection device according to claim 30, wherein The weight information is encoded information in which the weight of the pallet is embedded.

32. The weight detection device according to claim 27, wherein The weight detection device further includes a storage processing unit that stores, in a storage unit, the load information related to the load determined based on the appearance information in association with the estimated weight of the contents.

33. A weight detection method, executed by a computer, the weight detection method including: A detection step of detecting the appearance information of the load loaded on the pallet inserted by the fork; A determination step of determining the outer packaging other than the contents in the load based on the detected appearance information; and And An estimation step of estimating the weight of the contents based on the determined outer packaging.

34. A weight detection program that causes a computer to execute the following process: A detection process of detecting the appearance information of the load loaded on the pallet inserted by the fork; A determination process of determining the outer packaging other than the contents in the load based on the detected appearance information; and An estimation process of estimating the weight of the contents based on the determined outer packaging.

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