Industrial vehicle

Abstract

To provide an industrial vehicle that is able to realize stable traveling corresponding to the layout of a construction site while sufficiently securing workability.SOLUTION: A forklift 1 includes: a map information storage unit 16 that stores map information including layout information of a traveling area 21 in which an own vehicle travels and vehicle speed limit area information in the traveling area 21; a position sensor 11 that acquires position information of the own vehicle; and a traveling control unit 15 that controls traveling of the own vehicle. The vehicle speed limit area information includes a limit direction relative to a vehicle speed limit area 26. The traveling control unit 15 limits a vehicle speed of the own vehicle when the own vehicle enters the vehicle speed limit area 26 from a direction coinciding with the limit direction, based on the position information; and does not limit the vehicle speed of the own vehicle when the own vehicle enters the vehicle speed limit area 26 from a direction not coinciding with the limit direction.SELECTED DRAWING: Figure 2

Description

Technical Field

[0001] The present disclosure relates to industrial vehicles.

Background Art

[0002] As a type of industrial vehicle, there is, for example, a forklift described in Patent Document 1. In Patent Document 1, a forklift is equipped with a speed limiting device. The speed limiting device limits the traveling speed of the vehicle based on parameters such as the load capacity of the forks, the tipping moment of the mast, the height position of the forks, and the tilting angle of the mast back and forth.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] Technologies such as that of the above-mentioned Patent Document 1 aim to achieve stable running of industrial vehicles by limiting the traveling speed of the vehicle based on information of the own vehicle. However, at the site where industrial vehicles are actually introduced, there may be a need for driving rules according to the layout of the site. In this case, simply limiting the traveling speed of the vehicle based on information of the own vehicle may overly restrict the running of the industrial vehicle and reduce workability.

[0005] The present disclosure has been made to solve the above problems, and an object thereof is to provide an industrial vehicle that can realize stable running according to the layout of the site while sufficiently ensuring workability.

Means for Solving the Problems

[0006] The gist of the present disclosure is as follows.

[0007] [1] An industrial vehicle comprising: a storage unit that stores map information including layout information of a driving area in which the own vehicle travels and speed limit area information in the driving area; a position information acquisition unit that acquires position information of the own vehicle; and a driving control unit that controls the driving of the own vehicle, wherein the speed limit area information includes a limiting direction for the speed limit area, and the driving control unit implements a speed limit of the own vehicle when the own vehicle enters the speed limit area from a direction that coincides with the limiting direction based on the position information, and does not implement the speed limit of the own vehicle when the own vehicle enters the speed limit area from a direction that does not coincide with the limiting direction.

[0008] In this industrial vehicle, when the own vehicle enters the speed limit area from a direction that coincides with the limiting direction, the speed limit is implemented, and when the own vehicle enters the speed limit area from a direction that does not coincide with the limiting direction, the speed limit is not implemented. The speed limit area and the limiting direction for the speed limit area can be preset based on the layout of the driving area of the industrial vehicle. Therefore, in this industrial vehicle, while the speed limit can be appropriately implemented according to the layout of the site, unnecessary implementation of the speed limit can be avoided even in the same speed limit area. Accordingly, in this industrial vehicle, stable driving according to the layout of the site can be realized while sufficiently ensuring workability.

[0009] [2] The industrial vehicle according to [1], wherein when the driving control unit implements the speed limit of the own vehicle, it decreases the speed of the own vehicle at a constant acceleration until it reaches the end point of the speed limit area. In this case, rapid speed changes can be avoided in the speed limit area, and the driving stability can be further improved.

[0010] [3] The industrial vehicle according to [1] or [2], further comprising a weight information acquisition unit that acquires weight information of the own vehicle, wherein when the driving control unit implements the speed limit of the own vehicle, it decreases the speed of the own vehicle at a smaller acceleration as the weight of the own vehicle is larger. In this case, by reducing the deceleration according to the weight of the own vehicle, the driving stability can be ensured.

[0011] [4] A fork for holding a load, and a lift height information acquisition unit for acquiring lift height information of the fork. When implementing the vehicle speed limit of the host vehicle, the travel control unit decreases the speed of the host vehicle with a smaller acceleration as the lift height of the fork is greater. The industrial vehicle according to any one of [1] to [3]. In this case, by reducing the deceleration according to the lift height of the fork, the stability of travel can be ensured.

[0012] [5] It includes a reading unit for reading a first code and a second code arranged in the travel area. When the reading unit reads the codes in the order of the first code and the second code, the travel control unit determines that the host vehicle has entered the vehicle speed limit area from a direction that coincides with the restriction direction. When the reading unit reads the codes in the order of the second code and the first code, the travel control unit determines that the host vehicle has entered the vehicle speed limit area from a direction that does not coincide with the restriction direction. The industrial vehicle according to any one of [1] to [4]. In this case, the restriction direction in the vehicle speed limit area can be distinguished by a simple process. Also, by simply swapping the arrangement of the first coat and the second code, the change of the restriction direction can be easily performed.

Effect of the Invention

[0013] According to the present disclosure, stable travel according to the layout of the site can be realized while sufficiently ensuring workability.

Brief Description of the Drawings

[0014]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Figure 8

Figure 9

Mode for Carrying Out the Invention

[0015] Hereinafter, with reference to the drawings, a preferred embodiment of an industrial vehicle according to one aspect of the present disclosure will be described in detail.

[0016] FIG. 1 is a schematic side view showing the configuration of an industrial vehicle according to an embodiment of the present disclosure. In the present embodiment, as shown in FIG. 1, a forklift 1 is exemplified as the industrial vehicle. The forklift 1 may be either a manually operated vehicle or an automatically operated vehicle. The forklift 1 is, for example, a counterbalanced forklift. The forklift 1, for example, unloads a pallet P on which a load L is placed from a truck bed or the like, and travels to a predetermined load unloading position while holding it with the forks 7.

[0017] The forklift 1 includes a vehicle body 2, a pair of left and right front wheels 3 disposed at the front of the vehicle body 2, a pair of left and right rear wheels 4 disposed at the rear of the vehicle body 2, a mast 5 attached to the front end of the vehicle body 2, a pair of left and right forks 7 attached to the mast 5 via a lift bracket 6 so as to be liftable, a lift cylinder 8 for lifting and lowering the forks 7 via the lift bracket 6, and a tilt cylinder 9 for tilting the mast 5.

[0018] Figure 2 is a block diagram showing the functional components of the industrial vehicle shown in Figure 1. As shown in Figure 2, the forklift 1 includes a position sensor (position information acquisition unit) 11, a weight sensor (weight information acquisition unit) 12, a lift height sensor (lift height information acquisition unit) 13, a travel drive unit 14, a travel control unit 15, and a map information storage unit (storage unit) 16.

[0019] The position sensor 11 is a part that acquires the position information of the own vehicle. The acquisition of the position information is not particularly limited, and for example, indoor positioning technologies using UWB (Ultra Wide Band) or AR markers can be used. The position information includes, for example, coordinate information indicating the planar position of the own vehicle in the travel area 21 (see Figure 3). The position sensor 11 outputs the acquired position information of the own vehicle to the travel control unit 15.

[0020] The weight sensor 12 is a part that acquires the weight information of the own vehicle. The weight information acquired by the weight sensor 12 may be information indicating the weight of the load L held by the fork 7, or may be information indicating the total weight of the weight of the load L held by the fork 7 and the weight of the own vehicle. The weight sensor 12 outputs the acquired weight information of the own vehicle to the travel control unit 15.

[0021] The lift height sensor 13 is a part that acquires the lift height information of the fork 7. The lift height of the fork 7 is the height from the ground on which the forklift 1 travels to the upper surface of the horizontal part of the fork 7. The lift height sensor 13 outputs the acquired lift height information of the fork 7 to the travel control unit 15.

[0022] The travel drive unit 14 is a drive unit that drives the forklift 1 to travel. The travel drive unit 14 includes, for example, a travel motor, a steering motor, etc. Although not shown, the forklift 1 is provided with a lift drive unit in addition to the travel drive unit 14. The lift drive unit is a drive unit that expands and contracts the lift cylinder 8. The lift drive unit is constituted by, for example, an electromagnetic control valve arranged between a hydraulic pump and the lift cylinder 8.

[0023] The travel control unit 15 is a part that controls the travel of the forklift 1. Physically, it is a computer system composed of a CPU, RAM, ROM, input / output interfaces, etc. When in manual travel, the travel control unit 15 controls the travel drive unit 14 based on the operation data from the driver of the forklift 1, and when in automatic travel, it controls the travel drive unit 14 based on the pre-input operation data to make the forklift 1 travel. Also, the travel control unit 15 performs control related to vehicle speed limits during travel in the vehicle speed limit area 26 set in the travel area 21 of the forklift 1. When implementing the control related to vehicle speed limits, the travel control unit 15 refers to the map information stored in the map information storage unit 16.

[0024] Figure 3 is a diagram showing an example of the map information stored in the map information storage unit. As shown in Figure 3, the map information includes the layout information of the travel area 21 where the own vehicle travels and the vehicle speed limit area information in the travel area 21. In the example of Figure 3, in the travel area 21, there are a main road 22 with a wide road width and a plurality of narrow passages 25 with a narrow road width sandwiched between objects such as shelves 23 or walls 24. Each of the narrow passages 25 branches off from, for example, the main road 22 and extends in a direction orthogonal to the main road 22. In the travel area 21 shown by the map information, the areas of objects such as the main road 22, narrow passages 25, shelves 23, and walls 24 are represented by, for example, coordinate information indicating the planar positions of the corners of the areas.

[0025] The vehicle speed limit area 26 indicated by the vehicle speed limit area information is an area where the vehicle speed limit by the travel control unit 15 is implemented in the travel area 21. The vehicle speed limit area 26 is set for an area in the travel area 21 where attention is required for the travel of the forklift 1, such as an area with poor visibility. In the example of Figure 3, the vehicle speed limit area 26 is set over a predetermined distance at the end of the narrow passage 25, that is, at the entrance and exit of the narrow passage 25 with respect to the main road 22. The vehicle speed limit area 26 is represented by, for example, coordinate information indicating the planar positions of the corners of the area, similar to the areas of the objects in the travel area 21.

[0026] The vehicle speed limit area information is associated with information regarding the restricted direction for the vehicle speed limit area 26. The restricted direction indicates the driving direction in which the vehicle speed limit is imposed in the vehicle speed limit area 26. In the example of FIG. 3, in each of the vehicle speed limit areas 26, the restricted direction is set in the direction from the narrow passage 25 to the main passage 22.

[0027] Based on the position information received from the position sensor 11, the travel control unit 15 refers to the map information stored in the map information storage unit 16. When the host vehicle enters the vehicle speed limit area 26, it determines whether the entry direction thereof matches the restricted direction in the vehicle speed limit area 26. As shown in FIG. 4, when the entry direction of the host vehicle into the vehicle speed limit area 26 does not match the restricted direction, the travel control unit 15 does not implement the vehicle speed limit of the host vehicle, and controls the travel drive unit 14 so as to achieve the speed based on the driver's operation or a preset constant speed.

[0028] As shown in FIG. 5, when the entry direction of the host vehicle into the vehicle speed limit area 26 matches the restricted direction, the travel control unit 15 implements the vehicle speed limit of the host vehicle. In the present embodiment, whether the entry direction of the host vehicle matches the restricted direction is determined based on, for example, the coordinate information of the host vehicle based on the position information and the coordinate information of the vehicle speed limit area 26 based on the vehicle speed limit area information.

[0029] In the example of FIG. 6, one vehicle speed limit area 26 is represented by four coordinate information (10, 0), (10, 4), (20, 0), (20, 4) indicating the planar positions of the corners of the area. For such a vehicle speed limit area 26, when the coordinate information of the host vehicle acquired at a certain time is (9, 2) and the coordinate information of the host vehicle acquired at the next time is (11, 2), the travel control unit 15 determines that the host vehicle has entered the vehicle speed limit area 26 from the direction that matches the restricted direction.

[0030] FIG. 7(a) is a diagram showing an example of vehicle speed limit. In the present embodiment, when the traveling control unit 15 implements the vehicle speed limit of the host vehicle, the speed of the host vehicle is decreased at a constant acceleration until it reaches the end point of the vehicle speed limit area 26. In the example of FIG. 7(a), the speed of the host vehicle at the start point P 0 of the vehicle speed limit area 26 is V 0 . When this is the case, the traveling control unit 15 decreases the speed of the host vehicle at a constant acceleration so that the speed of the host vehicle at the end point P 1 of the vehicle speed limit area 26 becomes V 0 smaller than V 1 . The limit speed V 1 at the end point P 1 of the vehicle speed limit area 26 is preset based on the layout of the traveling area, such as the passage width of the narrow passage 25, for example.

[0031] FIG. 7(b) is a diagram showing another example of vehicle speed limit. In this other example, when the traveling control unit 15 implements the vehicle speed limit of the host vehicle, the greater the load weight (the weight of the host vehicle), the smaller the acceleration at which the speed of the host vehicle is decreased. Further, when the traveling control unit 15 implements the vehicle speed limit of the host vehicle, the greater the lifting height of the fork 7, the smaller the acceleration at which the speed of the host vehicle is decreased.

[0032] In the example of FIG. 7(b), the acceleration of the vehicle speed limit is set in consideration of both the load weight and the lifting height of the fork 7. Also, among the load weight and the lifting height, the acceleration of the vehicle speed limit is set with priority given to the lifting height. In the example of FIG. 7(b), the load weight is distinguished as either high weight / low weight based on a predetermined threshold value, and the lifting height of the fork 7 is distinguished as either high lifting height / low lifting height based on a predetermined threshold value. Then, the acceleration for each condition is set so that the acceleration of the vehicle speed limit decreases in the order of low lifting height / low weight, low lifting height / high weight, high lifting height / low weight, and high lifting height / high weight.

[0033] As described above, in the forklift 1, when the host vehicle enters the vehicle speed limit area 26 from a direction that coincides with the restricted direction, vehicle speed limitation is implemented, and when the host vehicle enters the vehicle speed limit area 26 from a direction that does not coincide with the restricted direction, vehicle speed limitation is not implemented. The vehicle speed limit area 26 and the restricted direction for the vehicle speed limit area 26 can be preset based on the layout of the traveling area 21 of the forklift 1. For this reason, in the forklift 1, while being able to appropriately implement vehicle speed limitation according to the layout of the site, implementation of unnecessary vehicle speed limitation can also be avoided even in the same vehicle speed limit area 26. Therefore, in the forklift 1, stable traveling according to the layout of the site can be realized while sufficiently ensuring workability.

[0034] In the present embodiment, when implementing vehicle speed limitation of the host vehicle, the traveling control unit 15 decreases the speed of the host vehicle at a constant acceleration until reaching the end point of the vehicle speed limit area 26. Thereby, a rapid speed change can be avoided in the vehicle speed limit area 26, and the traveling stability can be further improved.

[0035] In the present embodiment, when implementing vehicle speed limitation of the host vehicle, the traveling control unit 15 includes a mode in which the greater the weight of the host vehicle, the smaller the acceleration at which the speed of the host vehicle decreases. In this case, by reducing the deceleration according to the weight of the host vehicle, traveling stability can be ensured. Further, in the present embodiment, when implementing vehicle speed limitation of the host vehicle, the traveling control unit 15 includes a mode in which the greater the lifting height of the fork 7, the smaller the acceleration at which the speed of the host vehicle decreases. In this case, by reducing the deceleration according to the lifting height of the fork 7, traveling stability can be ensured.

[0036] The present disclosure is not limited to the above embodiments. For example, in the example of FIG. 7(b), among the load weight and the lifting height, the acceleration of the vehicle speed limit is set with priority given to the lifting height. Conversely, the acceleration of the vehicle speed limit may be set with priority given to the load weight. In this case, for example, the acceleration for each condition may be set so that the acceleration of the vehicle speed limit decreases in the order of low lifting height / low weight, high lifting height / low weight, low lifting height / high weight, and high lifting height / high weight. Also, for example, in the example of FIG. 7(b), the acceleration of the vehicle speed limit is set in consideration of both the load weight and the lifting height of the fork 7, but the acceleration of the vehicle speed limit may be set in consideration of only one of the load weight and the lifting height of the fork 7.

[0037] Further, in the above embodiment, based on the coordinate information of the host vehicle based on the position information and the coordinate information of the vehicle speed limit area 26 based on the vehicle speed limit area information, it is determined whether the entry direction of the host vehicle matches the restricted direction. However, whether the entry direction of the host vehicle matches the restricted direction may be determined by reading a code arranged in the driving area 21. As the code, for example, a two-dimensional code such as a QR code can be used.

[0038] In this aspect, for example, as shown in FIG. 8, the forklift 1 has a reading unit 31 as a position information acquisition unit. The reading unit 31 is constituted by a code reader that reads a code, and outputs the information acquired by reading the code as position information to the travel control unit 15. In the example of FIG. 9, a first code 32A and a second code 32B are arranged in the travel area 21. The first code 32A is arranged close to the boundary of the vehicle speed limit area 26 outside the vehicle speed limit area 26 and close to the boundary of the vehicle speed limit area 26 inside the vehicle speed limit area 26.

[0039] When the reading unit 31 reads the codes in the order of the first code 32A and the second code 32B, the travel control unit 15 determines that the host vehicle has entered the vehicle speed limit area 26 from the direction that coincides with the restricted direction. When the reading unit 31 reads the codes in the order of the second code 32B and the first code 32A, the travel control unit 15 determines that the host vehicle has entered the vehicle speed limit area 26 from the direction that does not coincide with the restricted direction. According to such an aspect, the restricted direction in the vehicle speed limit area 26 can be distinguished by simple processing. Further, by simply swapping the arrangements of the first code 32A and the second code 32B, the change of the restricted direction can be easily performed.

[0040] In the above embodiment, the forklift 1 is exemplified as the industrial vehicle. However, the industrial vehicle to which the present disclosure is applied is not limited to the forklift, and can be widely applied to other manned transport vehicles, unmanned transport vehicles capable of autonomous driving, transport robots capable of autonomous driving, towing vehicles, and the like.

Explanation of Signs

[0041] 1... Forklift (industrial vehicle), 7... Fork, 11... Position sensor (position information acquisition unit), 12... Weight sensor (weight information acquisition unit), 13... Lifting height sensor (lifting height information acquisition unit), 15... Travel control unit, 16... Map information storage unit (storage unit), 21... Travel area, 26... Vehicle speed limit area, 31... Reading unit, 32A... First code, 32B... Second code.

Claims

1. A storage unit that stores map information including layout information of a driving area where the vehicle travels and vehicle speed limit area information in the driving area; A position information acquisition unit that acquires position information of the host vehicle; A travel control unit that controls the travel of the host vehicle, comprising: The vehicle speed limit area information includes a limit direction for the vehicle speed limit area; When the host vehicle enters the vehicle speed limit area from a direction that coincides with the limit direction based on the position information, the travel control unit implements a vehicle speed limit for the host vehicle. When the host vehicle enters the vehicle speed limit area from a direction that does not coincide with the limit direction, the travel control unit does not implement a vehicle speed limit for the host vehicle. An industrial vehicle.

2. When implementing a vehicle speed limit for the host vehicle, the travel control unit decreases the speed of the host vehicle at a constant acceleration until reaching the end point of the vehicle speed limit area. The industrial vehicle according to Claim 1.

3. Comprising a weight information acquisition unit that acquires weight information of the host vehicle; When implementing a vehicle speed limit for the host vehicle, the travel control unit decreases the speed of the host vehicle at a smaller acceleration as the weight of the host vehicle increases. The industrial vehicle according to Claim 1.

4. Forks for holding a load; A lift height information acquisition unit that acquires lift height information of the forks, comprising: When implementing a vehicle speed limit for the host vehicle, the travel control unit decreases the speed of the host vehicle at a smaller acceleration as the lift height of the forks increases. The industrial vehicle according to Claim 1.

5. Comprising a reading unit that reads a first code and a second code arranged in the driving area; The travel control unit: When the reading unit reads the codes in the order of the first code and the second code, it determines that the host vehicle has entered the vehicle speed limit area from a direction that coincides with the limit direction; When the reading unit reads the codes in the order of the second code and the first code, it determines that the host vehicle has entered the vehicle speed limit area from a direction that does not coincide with the limit direction. The industrial vehicle according to any one of Claims 1 to 4.

Images