Industrial Vehicles

Abstract

To provide an industrial vehicle capable of easily switching between a normal mode and an operation limit mode that temporarily cancels an operation stop mode and restricts to low-speed running, even when an operator takes a posture of looking back when going backwards.SOLUTION: An industrial vehicle is provided with a car body, a drive seat provided in the car body, an obstacle detector that is mounted on the car body and detects an obstacle at the rear of the car body, a running drive device that generates driving force for running, and a controller that controls the running drive device. The controller switches from a normal mode M1 with no running limit to an operation stop mode M2 that stops running when the obstacle detector detects the obstacle. A mode switching device that temporarily cancels the operation stop mode M2 is provided behind a seat surface of the drive seat, and the controller temporarily cancels the operation stop mode M2 when the mode switching device is operated, and switches to the normal mode M1 or an operation limit mode M3 that limits to low-speed running.SELECTED DRAWING: Figure 4

Description

[Technical field]

[0001] The present invention relates to an industrial vehicle. [Background technology]

[0002] As a conventional technique related to industrial vehicles, for example, a construction vehicle disclosed in Patent Document 1 is known. The construction vehicle disclosed in Patent Document 1 is equipped with an actuator, an operating device, an obstacle detection device, a controller, and a control release device. The operating device is a device for instructing the operation of the actuator, and the obstacle detection device is a device for detecting surrounding obstacles. The controller performs operation limit control that limits the operation of the actuator when the obstacle detection device detects an obstacle. The control release device is a device for instructing the release of the operation limit control.

[0003] The controller has a normal mode in which the operation restriction control is enabled, and a temporary release mode in which the operation restriction control is temporarily released. In the normal mode, the controller transitions to the temporary release mode due to the operation of the control release device, and in the temporary release mode, the controller returns to the normal mode when a predetermined condition not due to the operation of the control release device is satisfied.

[0004] Specifically, if the ON time of the control release switch as a control release device is a short button press that stops pressing the control release switch before the release mode discrimination time is reached, the control mode state is switched to "temporary release." If the 3D sensor, which is an obstacle detection device, is in the "detection" state, detecting one or more obstacles around the vehicle body, the control mode state is not switched from "temporary release," and the non-detection time is reset to the initial value. The control release switch as a control release device is provided in the driver's cab.

[0005] According to the construction vehicle disclosed in Patent Document 1, the operation of the control release device switches the vehicle from a normal mode in which operational restrictions are activated to a temporary release mode in which operational restrictions are not activated, making it possible to ensure workability in situations where objects necessary for work are present around the vehicle body. In addition, when a predetermined condition not caused by the operation of the control release device is met in the temporary release mode, the vehicle returns to the normal mode without the operation of the control release device, making it possible to reduce the possibility of an accident occurring due to contact between the construction machine and nearby workers. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] Patent Publication No. 2021-50545 Summary of the Invention [Problem to be solved by the invention]

[0007] However, the construction vehicle disclosed in Patent Document 1 has a problem in that the control release device is provided in the driver's cab and is not necessarily provided in a position that corresponds to the operator's driving posture. For example, when reversing a forklift as an industrial vehicle, the operator may take a posture in which he looks back and steers with his left hand. In this case, even if a release switch for releasing the operation restriction of the forklift is provided in the driver's seat, it is difficult for the operator to operate the release switch. In particular, in the case of a forklift, since it is often necessary to repeatedly move forward and backward in narrow places surrounded by shelves that may become obstacles, it is required to release the restriction so that the operator's intention is quickly reflected.

[0008] The present invention has been made in consideration of the above problems, and an object of the present invention is to provide an industrial vehicle that can easily switch from the operation stop mode to an operation restricted mode that restricts driving to a low speed or to a normal mode, even if the operator looks back while reversing. [Means for solving the problem]

[0009] In order to solve the above problems, the present invention provides an industrial vehicle comprising a vehicle body, a driver's seat provided on the vehicle body, an obstacle detector mounted on the vehicle body and detecting obstacles rear of the vehicle body, a traveling drive device that generates driving force for traveling, and a controller that controls the traveling drive device, wherein the controller switches from a normal mode with no operation restrictions to an operation stop mode that stops operation when the obstacle detector detects an obstacle, and a mode switch that temporarily releases the operation stop mode is provided behind the seating surface of the driver's seat, and when the mode switch is operated, the controller temporarily releases the operation stop mode and switches to an operation restriction mode that restricts traveling to low speeds or the normal mode.

[0010] In the present invention, when the obstacle detector detects an obstacle, the normal mode with no travel restriction is switched to an operation stop mode in which travel is stopped, but the operation stop mode can be temporarily released by operating the mode switch to switch to an operation restricted mode in which travel is restricted to low speed or to the normal mode. Since the mode switch is provided behind the seat surface of the driver's seat, the mode switch is located in a position that is easy to operate for an operator who looks back when reversing. Therefore, even if the operator looks back when reversing, the operation stop mode can be temporarily released and the mode can be easily switched to the operation restricted mode or the normal mode by operating the steering wheel.

[0011] In the above industrial vehicle, the mode switch may be an operation button provided at the rear of the operator's seat. In this case, since the mode switch is an operation button provided at the rear of the driver's seat, the operation button at the rear of the driver's seat is easy to operate for an operator who is in a position that requires him to look back when reversing.

[0012] In addition, the above-mentioned industrial vehicle may be equipped with a head guard covering the upper part of the driver's seat, a rear pillar supporting the head guard and positioned rearward of the driver's seat, and a rear assist grip arranged along the rear pillar, and the mode switch may be configured to be a bar-shaped operation button arranged opposite the pillar side of the rear assist grip. In this case, since the mode switch is a bar-shaped operation button provided facing the rear pillar side of the rear assist grip, an operator who looks back when reversing can operate the mode switch while holding the rear assist grip. This makes it easier to temporarily release the operation stop mode and switch to the operation limited mode or normal mode.

[0013] Also, The present invention relates to an industrial vehicle comprising a vehicle body, a driver's seat provided on the vehicle body, an obstacle detector mounted on the vehicle body and detecting an obstacle behind the vehicle body, a travel drive device that generates a driving force for travel, and a controller that controls the travel drive device, wherein the controller switches from a normal mode with no operation restrictions to an operation stop mode in which operation is stopped when the obstacle detector detects an obstacle, and a mode switch that temporarily releases the operation stop mode is provided behind the seat surface of the driver's seat, a head guard covering an upper portion of the operator's seat, the mode switch being a proximity sensor installed on the head guard facing downward, the proximity sensor being installed so as to match the position of the head of an operator looking back; The controller is characterized in that, when the proximity sensor detects the head, it temporarily cancels the operation stop mode and switches to an operation limited mode that limits driving to a low speed or to the normal mode. In the present invention, The mode switch is a proximity sensor installed on the head guard, and is installed so as to match the position of the operator's head when the operator looks back. Therefore, when the operator looks back to move backward, the stop mode can be temporarily released and the operation mode can be easily switched to the operation limited mode or normal mode without operating the mode switch.

[0014] In the above industrial vehicle, the controller may be configured to temporarily cancel the operation stop mode and switch to the operation restricted mode while the mode switch is being operated. In this case, the operation stop mode is temporarily released and switched to the operation limited mode while the mode switch is being operated, and when the operation of the mode switch is no longer performed, the operation stop mode can be restored.

[0015] In the above-described industrial vehicle, the controller may be configured to continue releasing the operation stop mode when the vehicle speed is equal to or greater than a preset threshold value in the operation restricted mode. In this case, when the vehicle is in the operation restriction mode and the vehicle speed is above a preset threshold, the operation stop mode continues to be released, so that the vehicle can continue to travel at a vehicle speed above the threshold without returning to the operation stop mode, which stops travel, regardless of whether the mode switch is operated or not. Effect of the Invention

[0016] According to the present invention, an industrial vehicle can be provided that can easily switch from the operation stop mode to an operation restriction mode that restricts driving to a low speed or a normal mode even if the operator looks back while reversing. [Brief description of the drawings]

[0017] [Figure 1] FIG. 1 is a side view of a forklift according to a first embodiment. [Diagram 2] FIG. 1 is a rear view of a forklift according to a first embodiment. [Diagram 3] 1 is a schematic configuration diagram of a forklift according to a first embodiment. [Figure 4] FIG. 13A is a diagram showing a schematic relationship between a normal mode, an operation stop mode, and an operation restriction mode, and FIG. 13B is a list diagram showing the relationship between the operation restriction level and a path. [Diagram 5] FIG. 4 is a plan view for explaining the operation of the forklift. [Figure 6] FIG. 6 is a rear view of the forklift according to the second embodiment. [Figure 7] FIG. [Figure 8] FIG. 13(a) is a rear view of a forklift according to a third embodiment, and FIG. 13(b) is a side view of a main portion of the forklift. [Figure 9] FIG. 10 is a diagram showing operation buttons according to a modified example. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0018] (First embodiment) A forklift as an industrial vehicle according to a first embodiment will be described below with reference to the drawings. The forklift of this embodiment is a counterweight type forklift equipped with a counterweight. The terms "front / back", "left / right" and "up / down" that specify directions are based on the state in which the forklift operator is seated in the driver's seat and facing the forward direction of the forklift.

[0019] As shown in Fig. 1, the forklift 10 is provided with a loading device 12 at the front of a vehicle body 11. A driver's seat 13 is provided near the center of the vehicle body 11. Driving wheels 14 serving as front wheels are provided at the front of the vehicle body 11, and steering wheels 15 serving as rear wheels are provided at the rear of the vehicle body 11. A counterweight 16 is provided at the rear of the vehicle body 11, and the counterweight 16 is used to adjust the vehicle weight and achieve weight balance in the vehicle body 11. The forklift 10 of this embodiment is an electric forklift with a single steering wheel 15.

[0020] The driver's seat 13 in the vehicle body 11 is equipped with a driver's seat 17. The driver's seat 17 is equipped with a seat portion 18 having a seating surface on which the operator of the forklift 10 sits, and a backrest portion 19. The driver's seat 17 is located to the left of the center in the vehicle width direction (left-right direction) of the vehicle body 11, and can be rotated horizontally to a certain angle in a clockwise direction. By being located to the left of the center in the vehicle width direction of the vehicle body 11 and rotating to a certain angle in a clockwise direction, the operator can easily see behind the vehicle body 11 when the forklift 10 is moving backwards.

[0021] In the forklift 10 of this embodiment, as shown in Fig. 1 and Fig. 2, a seat index point SIP (Seat Index Point) is defined on the operator's seat 17. The seat index point SIP is a reference point of the seat defined by ISO (ISO 5353) or JIS (JIS A 8318) or the like, and is defined near the joint between the torso and thighs of a theoretical operator. As shown in Fig. 2, the operator's seat 17 of this embodiment is located to the left of the center in the vehicle width direction of the vehicle body 11, and therefore the seat index point SIP is located to the left of the center in the vehicle width direction of the vehicle body 11.

[0022] The cargo handling device 12 is equipped with a mast 20 having outer masts 21 and inner masts 22. The pair of left and right outer masts 21 are equipped with inner masts 22 that can slide inside the outer masts 21. A hydraulically operated tilt cylinder (not shown) is installed between the vehicle body 11 and the outer masts 21. The masts 20 tilt in the front-rear direction with their lower ends as a fulcrum by operation of the tilt cylinder. The masts 20 are provided with hydraulically operated lift cylinders 23. The inner masts 22 slide within the outer masts 21 and rise and fall by operation of the lift cylinders 23.

[0023] A pair of left and right forks 24 are attached to the mast 20 via lift brackets 25, and the lift brackets 25 are arranged to be raised and lowered relative to the inner mast 22. In other words, the lift brackets 25 can be raised and lowered relative to the mast 20. The left and right forks 24 have the same configuration.

[0024] The vehicle body 11 is provided with a head guard 26 that covers the upper part of the driver's seat 13. The head guard 26 is supported by a front pillar 27 erected from the front part of the vehicle body 11 and a rear pillar 28 erected from the rear part of the vehicle body 11. The head guard 26 is a known type. The head guard 26 is made up of a side beam 29 that is integrated with the front pillar 27 by a hollow structural member, and a lattice-shaped roof portion provided between a pair of left and right side beams 29. (not shown)and a rear beam 31 connecting the rear ends of the pair of left and right side beams 29. As shown in FIG. 2, the right rear pillar 28 is provided with a rear assist grip 32. The rear assist grip 32 is a handle that can be grasped. The rear assist grip 32 is used by the operator when reversing the forklift 10. ,right By gripping the rear assist grip 32 with the hand, the operator can easily maintain a posture looking backward.

[0025] 2, a pair of left and right rear combination lamps 33 are provided on the rear end surface of the rear beam 31. The rear combination lamps 33 are lamps in which a direction indicator 34, a brake light 35, and a back-up light 36 are integrally combined.

[0026] The forklift 10 of this embodiment is equipped with a front camera unit 40 and a rear camera unit 41 as obstacle detectors. The front camera unit 40 is a camera unit that detects obstacles in front of the vehicle body and is provided on the mast 20. The rear camera unit 41 is a camera unit that detects obstacles in the rear of the vehicle body and is provided on the rear beam 31 of the head guard 26. The front camera unit 40 and the rear camera unit 41 correspond to obstacle detectors. The cameras provided in the front camera unit 40 and the rear camera unit 41 are, for example, stereo cameras. The front camera unit 40 and the rear camera unit 41 process the captured images.

[0027] A controller 42 that controls each part of the forklift 10 is mounted on the vehicle body 11. As shown in Fig. 3, the controller 42 is connected to the front camera unit 40 and the rear camera unit 41. Since the controller 42 is connected to the front camera unit 40 and the rear camera unit 41, it determines the presence or absence of an obstacle from data obtained by image processing, and calculates the position of the obstacle and the distance to the obstacle.

[0028] The controller 42 is connected to a traveling drive device 43 that generates a driving force for traveling. As shown in Fig. 3, the controller 42 includes a CPU 44 as an arithmetic processing unit, and a storage unit 45 including a RAM, a ROM, and the like. The controller 42 may include dedicated hardware for executing at least a part of the various processes, such as an application specific integrated circuit (ASIC). The controller 42 may be configured as a circuit including one or more processors that operate according to a computer program, one or more dedicated hardware circuits such as an ASIC, or a combination thereof.

[0029] The traveling drive device 43 has a driving motor 46 for traveling to rotate the driving wheels 14, and a motor driver 47 for controlling the power supplied to the driving motor 46. The rotation of the driving motor 46 is transmitted to the driving wheels 14 via a power transmission mechanism, causing the driving wheels 14 to rotate. The motor driver 47 controls the power supply to the driving motor 46 based on a command from the controller 42. The motor driver 47 detects the rotation speed of the driving motor 46, and the controller 42 calculates the vehicle speed based on the rotation speed.

[0030] The controller 42 is connected to an accelerator pedal sensor 49 that detects the depression amount of the accelerator pedal 48 and a lever position sensor 51 that detects the position of the forward / reverse lever 50. The depression amount of the accelerator pedal 48 detected by the accelerator pedal sensor 49 and the position of the forward / reverse lever 50 detected by the lever position sensor 51 are transmitted to the controller 42. The accelerator pedal 48 and the forward / reverse lever 50 are both provided at the driver's seat 13. The forward / reverse lever 50 is positioned at any one of a forward position (F), a reverse position (R) and a middle position (N) by an operation of an operator. The controller 42 is also connected to an alarm device 52. The alarm device 52 is, for example, a display device (not shown) that displays a warning by lighting or an alarm sound generator (not shown) that generates an alarm sound by a buzzer or the like. In this embodiment, the alarm device 52 is activated when an obstacle is detected by the front camera unit 40 and the rear camera unit 41.

[0031] In this embodiment, an operation button 53 serving as a mode switch is provided on the back of the backrest 19 of the operator's seat 17 (see FIG. 2). The operation button 53 is a button for mainly switching the operation mode of the forklift 10 when moving backward, and is connected to the controller 42. The operation button 53 has a function of temporarily releasing the operation stop mode, which will be described next, and switching to the normal mode or the operation restricted mode. In this embodiment, the operation buttons 53 are provided on the left and right sides of the back, but are often viewed from the right rear pillar 28 side where the rear assist grip 32 is provided. The position of the operation button is rearward of the seat reference point SIP in the front-rear direction, and more specifically, rearward of the seat surface of the seat portion 18.

[0032] As shown in FIG. 4(a), the forklift 10 can be in one of three modes: a normal mode M1 in which the forklift 10 can travel freely without any restrictions, an operation stop mode M2 ​​in which the forklift 10 is restricted from traveling, and an operation restricted mode M3 in which the forklift 10 is restricted to traveling at a low speed below a predetermined speed.

[0033] The normal mode M1 is an unconditional restriction release mode in which the rear camera unit 41 does not detect any obstacles and the forklift 10 can travel freely without any restrictions. Therefore, when the operator depresses the accelerator pedal 48, the controller 42 controls the travel drive device 43 in accordance with the amount of depression of the accelerator pedal 48. The vehicle speed can be increased up to the maximum speed.

[0034] The operation stop mode M2 ​​is a mode in which operation is restricted and switched to by the controller 42 when an obstacle is detected by the rear camera unit 41 during reverse travel. In the operation stop mode M2, the controller 42 controls the traveling drive device 43 to stop the output of the drive motor 46, and the forklift 10 does not travel and remains stopped even if the operator depresses the accelerator pedal 48. Incidentally, if the front camera unit 40 detects an obstacle during forward travel, the controller 42 performs control to activate the warning device 52 but not to restrict operation.

[0035] The operation restriction mode M3 is a partial restriction release mode in which the operation restriction is partially released. Specifically, in the operation restriction mode M3, the controller 42 controls the traveling drive device 43 to suppress the output of the drive motor 46, and the forklift 10 can travel, but the vehicle speed is restricted to a predetermined vehicle speed or less (e.g., 3 km / h). Therefore, even if the operator depresses the accelerator pedal 48, the forklift 10 travels at a speed equal to or less than the predetermined vehicle speed.

[0036] In this embodiment, the controller 42 controls each mode and also controls switching of modes when specific conditions are satisfied. The controller 42 also switches modes in response to the operation of the operation button 53 by the operator.

[0037] If the mode switching from the normal mode M1 to the operation stop mode M2 ​​is defined as path A, path A is established under the condition that an obstacle is present within the detection range of the rear camera unit 41 in the normal mode M1 and the restriction release operation is not performed by operating the operation button 53. Also, if the mode switching from the operation stop mode M2 ​​to the operation restriction mode M3 is defined as path B, path B is established under the condition that an obstacle is present within the detection range S (see FIG. 5) of the rear camera unit 41 in the operation stop mode M2 ​​and the restriction release operation is performed by operating the operation button 53. Specifically, the controller 42 is set so that path B is established when the operation button 53 is continuously pressed in the operation stop mode M2. The condition for releasing the restriction by path B is that the operation button 53 is no longer pressed.

[0038] Furthermore, if the mode switching from the operation restricted mode M3 to the normal mode M1 is designated as path C, path C is established under the condition that there is no obstacle within the detection range of the rear camera unit 41 in the operation restricted mode M3, or the vehicle travels in a direction different from the detection range of the rear camera unit 41. In path C, the restriction release operation is not performed by operating the operation button 53. If the mode switching from the normal mode M1 to the operation restricted mode M3 is designated as path D, path D is established under the condition that there is an obstacle within the detection range of the rear camera unit 41 in the normal mode M1, and the restriction release operation is performed by operating the operation button 53.

[0039] If the mode switching from the operation restricted mode M3 to the operation stopped mode M2 ​​is Path E, then Path E is established under the condition that the forklift 10 is stopped in the operation restricted mode M3 and the restriction release operation is released. In Path E, the restriction release operation is not performed by operating the operation button 53. If the mode switching from the operation restricted mode M3 to the normal mode M1 is Path F, then Path F is established under the condition that an obstacle is present within the detection range of the rear camera unit 41 in the operation restricted mode M3 and the restriction release operation is performed by operating the operation button 53. Specifically, the controller 42 is set so that Path F is established by the operation button 53 being continuously pressed in the operation stopped mode M2. The condition for releasing the restriction by Path B is that the operation button 53 is no longer pressed.

[0040] A path G is set in which the normal mode M1 is not switched to any mode other than the normal mode M1, and the path G is established under the condition that a restriction release operation is performed by operating the operation button 53 in the normal mode M1. Specifically, the path G is set in the controller 42 so that the path G is established when the operation button 53 is pressed once in the normal mode M1. The condition for canceling the restriction release by the paths B, D, F, and G is that the vehicle speed of the forklift 10 becomes 0 for a period of time exceeding a preset time.

[0041] As shown in FIG. 4(b), operation restriction levels are set for each of the paths B, D, F, and G that require the release operation of the operation button 53. Level 1 is a level in which the mode is normal M1 before the release operation and there is no operation restriction after the release operation, and corresponds to path G. Level 2 is a level in which the mode is normal M1 before the release operation and there is no operation restriction after the release operation, and corresponds to path D. Level 3 is a level in which the mode is stopped before the release operation and there is no operation restriction after the release operation, and corresponds to path F. Level 4 is a level in which the mode is stopped before the release operation and there is no operation restriction after the release operation, and corresponds to path B.

[0042] No levels are set for Paths A, C, and E because they do not require the release operation of the operation button 53. In the case of Path F, which is Level 3, it is set so that it will not switch to Paths D and G even if it switches to normal mode M1 after the release operation of the operation restriction. The controller 42 displays each of the levels 1 to 4 and each of the modes M1 to M3 on a display device provided in the driver's seat 13.

[0043] The operation restrictions of both paths B and F are released by operating the operation button 53 in the operation stop mode M2. For the release of the operation restrictions in the operation stop mode M2, the operator selects a level in advance and sets it in the controller 42. As a result, when the operation button 53 is pressed in the operation stop mode M2, the operation restrictions are released corresponding to the paths of the set level. Also, the operation restrictions of both paths G and D are released by operating the operation button 53 in the normal mode M1. For the release of the operation restrictions in the normal mode M1, the operator selects a level in advance and sets it in the controller 42. As a result, when the operation button 53 is pressed in the normal mode M1, the operation restrictions are released corresponding to the paths of the set level.

[0044] Next, the operation of the forklift 10 of this embodiment will be described. As shown in Fig. 5, the case where the forklift 10 performs cargo handling work in the passage between shelves T1 and T2 will be described. The operation of the forklift 10 when moving backward will also be described. In Fig. 5, the area surrounded by a dashed line behind the forklift 10 is the detection range S in which the rear camera unit 41 detects obstacles.

[0045] As shown in FIG. 5, in an aisle between shelves T1 and T2, when the forklift 10 places a load (not shown) on shelf T1, for example, the operator of the forklift 10 enters the aisle between shelves T1 and T2 (see the forklift moving in the direction of arrow P1 in FIG. 5). At this time, the forklift 10 is traveling in normal mode M1 and is not subject to operational restrictions. When the forklift 10 enters the aisle, the operator repeatedly moves the forklift 10 forward and backward with respect to the destination on shelf T1, aligning the forklift 10 with the destination on shelf T1 (see the forklift moving in the direction of arrow P2 in FIG. 5). When moving forward, the operator places the forward / reverse lever 50 in the forward position and depresses the accelerator pedal 48, and when moving backward, the operator places the forward / reverse lever 50 in the reverse position and depresses the accelerator pedal 48.

[0046] When the forklift 10 moves backwards to align with the shelf T1, the rear camera unit 41 detects the rear shelf T2, which is included in the detection range S, as an obstacle. If the shelf T2 is detected as an obstacle and the operator does not operate the operation button 53, the controller 42 determines that the establishment condition of the path A is satisfied, and the forklift 10 enters the operation stop mode M2 ​​and is subject to operation restrictions. In the operation stop mode M2, the forklift 10 cannot travel.

[0047] If the forklift 10 had to stop traveling every time the rear camera unit 41 detected an obstacle while the forklift 10 was moving backwards, the efficiency of loading and unloading work by the forklift 10 would be significantly impaired. For this reason, the operator presses the operation button 53 while moving backwards. There are cases where the operation restriction is released after the operation restriction due to the operation stop mode M2 ​​is imposed, and cases where the operation restriction is released before the restriction is imposed so as not to switch from the normal mode M1 to the operation stop mode M2.

[0048] In the case of releasing the operation restriction after being subjected to the operation restriction by the operation stop mode M2, the operator operates the operation button 53 during reverse travel. Specifically, the operator takes a posture in which he or she looks back, steers the steering wheel (not shown) with the left hand, and continues to press the operation button 53 with the right hand. When the forward / reverse lever 50 is in the reverse position, the accelerator pedal 48 is depressed, and the operation button 53 is continued to be pressed, Path B or Path F is established.

[0049] If the level preset in the controller 42 is level 4, the controller 42 controls the traveling drive device 43 to switch to the operation restricted mode M3 by path B. If the level preset in the controller 42 is level 3, the controller 42 controls the traveling drive device 43 to switch to the normal mode M1 by path F. When switched to the normal mode M1, the forklift 10 can move backward without being restricted from operating. When switched to the operation restricted mode M3, the forklift 10 can move backward, but is restricted to a low speed.

[0050] Next, a case will be described in which the operation restriction is released before the restriction is imposed so as not to change from normal mode M1 to operation stop mode M2. In this case, the operator performs an operation of pressing the operation button 53 once in normal mode M1. Specifically, for example, the operator performs an operation of turning the right hand (or left hand) to the back of the driver's seat 17 and pressing the operation button 53 once in normal mode M1 (when moving forward or stopped). At this time, path D or path G is established.

[0051] If the level preset in the controller 42 is level 2, the controller 42 controls the traveling drive device 43 to switch to the operation restriction mode M3 by path D. Therefore, even if the rear camera unit 41 detects an obstacle during reverse travel in the operation restriction mode M3, the mode is not switched to the operation stop mode M2. If the level preset in the controller 42 is level 1, the controller 42 controls the traveling drive device 43 to continue the normal mode M1 without switching from the normal mode M1 to the operation stop mode M2 ​​by path G. Since the normal mode M1 by path G continues, the normal mode M1 is maintained even if the rear camera unit 41 detects an obstacle during reverse travel. If the vehicle speed of the forklift 10 exceeds a preset time and becomes 0, the release of the restriction by path G is canceled.

[0052] The operation restricted mode M3 is switched to the operation stopped mode M2 ​​when path E is established. Path E can be established if the condition that the restriction release by path B is released and the rear camera unit 41 detects an obstacle during reverse travel is satisfied. When the condition of path E is satisfied, the controller 42 controls the traveling drive device 43 to switch from the operation restricted mode M3 to the operation stopped mode M2. Also, the operation restricted mode M3 is switched to the normal mode M1 when path C is established. Path C is established when the obstacle detected by the rear camera unit 41 disappears or the forklift 10 moves in a direction in which the rear camera unit 41 no longer detects the obstacle (see the forklift 10 moving toward the arrow P3 in FIG. 5).

[0053] The forklift 10 according to the present embodiment has the following advantages. (1) When the rear camera unit 41, which is an obstacle detector, detects an obstacle, the normal mode M1, which has no travel restrictions, is switched to an operation stop mode M2, which stops travel, but by operating the operation button 53, which is a mode switcher, the operation stop mode M2 ​​is temporarily released and the mode is switched to an operation limit mode M3, which limits travel to a low speed, or to the normal mode M1. Since the operation button 53 is provided behind the seat surface of the driver's seat 17, the operation button 53 is located in a position that is easy to operate for an operator who looks back when reversing. Therefore, even if the operator looks back when reversing, the operator can perform a steering operation and easily switch to the operation limit mode M3, which temporarily releases the operation stop mode M2 ​​and limits travel to a low speed, or to the normal mode M1.

[0054] (2) The mode switch is an operation button 53 provided at the rear of the operator's seat 17. For this reason, the operation button 53 at the rear of the operator's seat 17 is easy to operate for an operator who looks back when reversing. In addition, providing the operation button 53 on the operator's seat 17 is convenient in terms of handling the harness that connects the operation button 53 and the controller 42, and makes the assembly work of the operation button 53 easier.

[0055] (3) The controller 42 temporarily cancels the operation stop mode M2 ​​and switches to the operation limited mode M3 while the operation button 53 is being operated. Therefore, when the operation button 53 is no longer being operated, it is possible to switch to the operation stop mode M2.

[0056] (4) Even if the operator looks back while reversing, the steering operation can be performed and the operation restriction can be temporarily released, so that the forklift 10 can travel while giving priority to the operator's intention even in a narrow environment surrounded by obstacles. As a result, it is possible to prevent a decrease in efficiency of loading and unloading work caused by operation restrictions due to the detection of obstacles.

[0057] (5) Since a path for releasing the restriction according to the level can be selected in advance and set in the controller 42, the operator's intention is more easily reflected by the release of the operation restriction by the operation button 53. Also, each operator can select a path for releasing the restriction according to the level in advance according to his / her preference and set it in the controller 42.

[0058] (6) In the operation stop mode M2, the operator can release the operation restriction by continuing to press the operation button 53, and can return to the operation stop mode M2 ​​by stopping pressing the operation button 53. Therefore, the operator can intuitively understand the restriction due to the detection of an obstacle and the release of the restriction by operating the operation button 53.

[0059] Second embodiment Next, a forklift according to a second embodiment will be described. In this embodiment, the configuration of the mode switch is different from that of the first embodiment. In this embodiment, the same configuration as that of the first embodiment will be described with reference to the first embodiment, and common reference numerals will be used.

[0060] 6, a forklift 60 of this embodiment has a rear assist grip 61 equipped with an operation button 62. The rear assist grip 61 is provided on the right rear pillar 28 so as to face the operator's seat 17.

[0061] As shown in Fig. 7, the rear assist grip 61 has a grip portion 63, an upper leg portion 64, and a lower leg portion 65. The grip portion 63 is a portion of the rear assist grip 61 that is approximately parallel to the rear pillar 28. The upper leg portion 64 extends from an upper end of the grip portion 63 of the rear assist grip 61 toward the rear pillar 28 and is fixed to the rear pillar 28. The lower leg portion 65 extends from a lower end of the grip portion 63 of the rear assist grip 61 toward the rear pillar 28 and is fixed to the rear pillar 28. The upper leg portion 64 is provided with a horn button (not shown) for generating a warning sound when operated by the operator.

[0062] The operation button 62 is a bar-shaped button that extends along the longitudinal direction of the grip portion 63, and is provided in a position facing the rear pillar 28. For this reason, the button is easy for the operator to operate while gripping the rear assist grip 61 when reversing.

[0063] In this embodiment, the controller 42 controls the traveling drive device 43 so that, in the case of restriction release by paths B and F, the restriction is released by pressing the operation button 62 once. The controller 42 controls the traveling drive device 43 so as to switch to the normal mode M1 when the vehicle speed is equal to or greater than a preset threshold in the operation restricted mode M3 resulting from release of the operation restriction in the operation stop mode M2. The threshold value of the vehicle speed is, for example, the maximum speed in the operation restricted mode M3 (e.g., 3 [km / h]). Note that the threshold value of the vehicle speed is not limited to the maximum speed in the operation restricted mode M3.

[0064] The forklift 60 according to this embodiment has the same effects as the effects (1), (4), and (5) of the first embodiment. In addition, when the vehicle speed is equal to or higher than a preset threshold in the operation restriction mode M3, the release of the operation restriction in the operation stop mode M2 ​​is continued, so that the vehicle can travel at a vehicle speed equal to or higher than the threshold without returning to the operation stop mode M2 ​​in which traveling is stopped regardless of whether the operation button 62 is operated. In addition, since the operation button 62 is a bar-shaped button, it is easy to press using multiple fingers, and can also be pressed with the bottom of the palm. Furthermore, since the operation button 62 is located on the side facing the rear pillar 28, objects are unlikely to interfere with the operation button 62, and the operator is unlikely to unintentionally release the restriction.

[0065] (Third embodiment) Next, a forklift according to a third embodiment will be described. In this embodiment, the configuration of the mode switch is different from that of the first embodiment. In this embodiment, the same configuration as that of the first embodiment will be described with reference to the first embodiment, and common reference numerals will be used.

[0066] As shown in Figures 8(a) and 8(b), in a forklift 70 of this embodiment, the head guard 26 is provided with a proximity sensor 71 serving as a mode switch. The proximity sensor 71 is a photoelectric sensor having a light receiving and emitting unit 72, and is fixed near the rear beam 31 of the head guard 26 with the light receiving and emitting unit 72 facing downward. The position of the light receiving and emitting unit 72 is located behind the operator's seat 17 in the front-to-rear direction. The proximity sensor 71 is connected to the controller 42, and a light beam from the light receiving and emitting unit 72 is reflected downward on the upper surface of the vehicle body, and the light receiving and emitting unit 72 receives the reflected light, but transmits a signal to the controller 42 when the reflected light is blocked.

[0067] The proximity sensor 71 is provided at a position where it can detect the head of the operator when the operator looks back, but does not detect the head of the operator when the operator looks forward. In other words, the proximity sensor 71 is installed so as to match the position of the head of the operator when he looks back.

[0068] In this embodiment, even if an obstacle is detected during reverse travel, the operation restriction of the operation stop mode M2 ​​can be released by detecting the head of the operator looking back when the proximity sensor 71 detects it. In other words, since the mode switch is the proximity sensor 71, the operation stop mode M2 ​​can be temporarily released and the mode can be easily switched to the normal mode M1 or the operation restriction mode M3 by the operator looking back to reverse travel without operating the mode switch.

[0069] (Modification) 9 is an example in which an operation button 82 is provided on a rear pillar 81 that does not have a rear assist grip. The operation button 82 is an easy-to-operate button that can be operated while gripping the rear pillar 81 when reversing.

[0070] The present invention is not limited to the above-described embodiment, and various modifications are possible within the scope of the spirit of the invention. For example, the following modifications may be made.

[0071] In the above embodiment (including the modified example), the mode switch is provided on either the driver's seat or the rear assist grip, but this is not limited to this. The driver's seat or the rear assist grip may each be provided with a mode switch. In the second embodiment, a bar-shaped operation button serving as a mode switch is provided on the rear assist grip of the rear pillar of the forklift as an industrial vehicle, but this is not limited to this. The mode switch may be a proximity sensor (photoelectric sensor or ultrasonic sensor) provided on the rear assist grip instead of the bar-shaped operation button. In this case, the restriction can be released when the rear assist grip is gripped, and there is no need to operate the mode switch. In the first embodiment, the operation button serving as the mode switch is provided on the backrest of the driver's seat, but this is not limited to this. The operation button may be provided on the seat or an accessory of the driver's seat as long as it is located behind the seat reference point or the seat surface and within the reach of the operator. In the above embodiment (including the modified example), the restriction is released by pressing and holding the operation button or by pressing the operation button once, but this is not limited to this. There is no particular limit to the number of times the operation button is pressed, and one of multiple restriction release paths may be selected depending on the number of times the operation button is pressed. In the above embodiment (including the modified example), a forklift is used as an example of an industrial vehicle, but the present invention is not limited to this. The industrial vehicle is not limited to a forklift, but may be, for example, a towing tractor or a construction vehicle that allows the operator to drive backwards while looking back. [Explanation of symbols]

[0072] 10, 60, 70 Forklift 11 Body 12 Cargo handling equipment 13 Driver's seat 17 Driver's seat 26 Head Guard 28, 81 Rear pillar 32, 61 Rear assist grip 40 Front camera unit 41 Rear camera unit 42 Controller 43 Traveling drive unit 46 Drive motor 47 Motor Driver 48 Accelerator pedal 49 Accelerator pedal sensor 50 Forward / reverse lever 51 Lever position sensor 53, 62, 82 Operation button (mode switch) 70 Forklift 71 Proximity sensor (mode switch) A, B, C, D, E, F, G Paths M1 Normal Mode M2 deactivation mode M3 operation restriction mode S Detection range T1, T2 shelves

Claims

1. The car body and A driver's seat provided in the vehicle body; an obstacle detector mounted on the vehicle body to detect an obstacle behind the vehicle body; A traveling drive device that generates a driving force for traveling; A controller for controlling the traveling drive device, In the industrial vehicle, the controller switches from a normal mode with no operation restriction to an operation stop mode in which operation is stopped when the obstacle detector detects an obstacle, a mode switch for temporarily releasing the operation stop mode is provided behind the seat surface of the driver's seat, The industrial vehicle is characterized in that, when the mode switch is operated, the controller temporarily cancels the operation stop mode and switches the mode to an operation limited mode which limits driving to a low speed or to the normal mode.

2. 2. The industrial vehicle according to claim 1, wherein the mode switch is an operation button provided at the rear of the driver's seat.

3. A head guard covering an upper portion of the driver's seat; a rear pillar supporting the head guard and positioned rearward of the driver's seat; A rear assist grip is provided along the rear pillar, 2. The industrial vehicle according to claim 1, wherein the mode switch is a bar-shaped operation button provided opposite to the pillar side of the rear assist grip.

4. A vehicle body, A driver's seat provided in the vehicle body; an obstacle detector mounted on the vehicle body to detect an obstacle behind the vehicle body; A traveling drive device that generates a driving force for traveling; A controller for controlling the traveling drive device, In the industrial vehicle, the controller switches from a normal mode with no operation restriction to an operation stop mode in which operation is stopped when the obstacle detector detects an obstacle, a mode switch for temporarily releasing the operation stop mode is provided behind the seat surface of the driver's seat, A head guard is provided to cover an upper portion of the driver's seat, the mode switch is a proximity sensor that is installed on the head guard and faces downward, The proximity sensor is installed so as to match the position of the head of an operator who looks back, The industrial vehicle is characterized in that, when the proximity sensor detects the head, the controller temporarily cancels the operation stop mode and switches to an operation restricted mode which restricts driving to a low speed or to the normal mode.

5. 4. The industrial vehicle according to claim 1, wherein the controller temporarily cancels the operation stop mode and switches the mode to the operation restriction mode while the mode switch is being operated.

6. 6. The industrial vehicle according to claim 5, wherein the controller switches the mode to the normal mode when the vehicle speed in the operation restriction mode is equal to or higher than a preset threshold value.

Images