Loading platform lifting device and vehicle

Abstract

The present invention provides a loading platform lifting device that allows for stable climbing onto and off the loading platform of a vehicle using the loading platform as a stepping stool. [Solution] The loading platform lifting device 40 is mounted on a vehicle 10 having a loading platform 30 and is used for loading and unloading cargo by moving up and down between the ground and the floor surface 31 of the loading platform 30. The device comprises a loading platform 45 that moves up and down in a substantially horizontal position, a drive device 50 that moves the loading platform 45 up and down, and a control device 100 that controls the drive device 50. The control device 100 stops the loading platform 45 at a preset third position P3 between a first position P1 which is at substantially the same height as the ground and a second position P2 which is at substantially the same height as the floor surface 31 of the loading platform 30.

Description

Technical Field

[0004] ,

[0005] ,

[0001] The present invention relates to a load receiving platform lifting device and a vehicle equipped with the load receiving platform lifting device.

Background Art

[0002] Vehicles equipped with a load receiving platform lifting device for lifting and lowering a load receiving platform have been conventionally known. For example, Patent Document 1 discloses a vehicle including a load bed, a loading platform (load receiving platform), and a parallel link mechanism for supporting the loading platform, and a load receiving device for lifting and lowering the loading platform by the operation of the parallel link mechanism. When using the loading platform in the vehicle described in Patent Document 1, the loading platform is lifted and lowered in a substantially horizontal posture. The vehicle described in Patent Document 1 stores the loading platform in two modes: a floor pressing state in which the loading platform is folded and pulled under the floor, and a standing storage state in which the loading platform is vertically leaned against the rear surface of the load bed.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] In a vehicle equipped with a load receiving platform lifting device, in the operation of loading and unloading goods, an operator may climb onto and off the load bed using the load receiving platform as a step. In that case, the operator positions the load receiving platform at an intermediate height between substantially the same height as the ground and substantially the same height as the load bed. However, since there is variation in the operation of moving the load receiving platform, the load receiving platform may not be positioned at an appropriate height as a step. Therefore, the operation of climbing onto and off the load bed using the load receiving platform as a step cannot always be performed stably.

[0005] The present invention has been made in view of the above, and its purpose is to provide a loading platform lifting device that allows for stable climbing onto and off the loading platform of a vehicle using the loading platform as a stepping stool. [Means for solving the problem]

[0006] The loading platform lifting device disclosed herein is mounted on a vehicle having a loading platform and is used for loading and unloading cargo by moving up and down between the ground and the floor surface of the loading platform, and comprises a loading platform that moves up and down in a substantially horizontal position, a drive device for moving the loading platform up and down, and a control device for controlling the drive device. The control device includes an intermediate stop unit that stops the loading platform at a preset third position between a first position which is substantially the same height as the ground and a second position which is substantially the same height as the floor surface of the loading platform.

[0007] With this loading platform lifting device, the loading platform can be stopped at a predetermined third position. When using the loading platform as a stepping stone to climb onto and off the loading platform, setting the height of the loading platform to the third position prevents the height of the loading platform from changing each time work is performed. This allows for stable climbing onto and off the loading platform using the loading platform as a stepping stone.

[0008] In one preferred embodiment, the loading platform lifting device further comprises: an operating unit connected to the control device and operating the drive device via the control device; and a mode selection unit connected to the control device and capable of selecting one mode from a plurality of modes, including a first mode and a second mode, for control of the drive device. The control device is configured such that, when the first mode is selected, the operating unit can operate the drive device even when the loading platform is in the third position. The intermediate stop unit stops the loading platform at the third position, even when the operating unit is operating the drive device, when the second mode is selected.

[0009] In this configuration, after the loading platform is stopped at the third position in the second mode, it cannot be raised or lowered unless the mode is changed to the first mode. Therefore, it is possible to prevent the loading platform from being moved from the third position due to operational errors of the control unit, etc.

[0010] In another preferred embodiment, the loading platform lifting device further comprises an operating unit connected to the control device and for operating the drive device via the control device. The intermediate stop unit prevents the operation of the drive device by the operating unit after the loading platform has been stopped at the third position until predetermined conditions are met.

[0011] According to this configuration, once the loading platform is stopped at the third position, it cannot be raised or lowered unless predetermined conditions are met. Therefore, it is possible to prevent the loading platform from being moved from the third position due to operational errors or other reasons.

[0012] According to one preferred embodiment of the above, the operating unit is equipped with a button for raising and lowering the loading platform. The predetermined condition includes the cessation of pressing the button after the loading platform has stopped at the third position.

[0013] In this configuration, after pressing the button to stop the loading platform in the third position, the operation is stopped, and the next button press becomes effective. Therefore, restarting the drive unit becomes very easy.

[0014] In another preferred embodiment, the loading platform lifting device further comprises a foot switch provided on the loading platform. The predetermined condition includes the foot switch being pressed and then released.

[0015] In this configuration, since the foot switch on the loading platform was pressed and then released, it can be inferred that after the worker stepped onto the loading platform, they either climbed onto the loading platform or stepped off onto the ground. In such a situation, it is considered acceptable to move the loading platform from the third position. Therefore, the fact that the foot switch was pressed and then released is an appropriate condition for reactivating the operation of the control unit.

[0016] In another preferred embodiment, the loading platform lifting device further comprises an imaging device for imaging the loading platform. The control device includes a person recognition unit that recognizes a person from the image captured by the imaging device. The predetermined condition includes the determination by the person recognition unit that a person has moved away from the loading platform after getting on it.

[0017] In this configuration, the image captured by the imaging device can be used to recognize that a worker has stepped onto the loading platform and then moved away from it. Therefore, the determination made by the person recognition unit based on the image from the imaging device is appropriate as a condition for reactivating the operation of the control unit.

[0018] In another preferred embodiment, the loading platform lifting device further comprises a human presence sensor for detecting a person on the loading platform. The control device comprises a human presence recognition unit for acquiring the detection result of the human presence sensor. The predetermined condition includes the determination by the human presence recognition unit that a person has stepped onto the loading platform and then left it.

[0019] In this configuration, the detection result of the human presence sensor can be used to recognize that a worker has stepped onto the loading platform and then left it. Therefore, the determination made by the human presence sensor is appropriate as a condition for reactivating the operation of the control unit.

[0020] In another preferred embodiment, the loading platform lifting device further comprises a weight sensor for measuring the weight of an object placed on the loading platform. The predetermined condition includes that the weight measured by the weight sensor has increased and then decreased.

[0021] According to such an aspect, it is possible to estimate that the operator has left the loading platform after getting on the loading platform from the increase or decrease in the weight measured by the weight sensor. Therefore, the determination based on such a weight sensor is appropriate as a condition for making the operation of the operation unit effective again.

[0022] According to a preferred aspect, when the intermediate stop unit raises the loading platform from the first position, the loading platform is stopped at the third position, and when the loading platform is lowered from the second position, the loading platform is stopped at a fourth position different from the third position and between the first position and the second position.

[0023] The appropriate height of the step when getting on the platform and the appropriate height of the step when getting off the platform can be different heights. According to such an aspect, the third position mainly used when getting on the platform and the fourth position mainly used when getting off the platform can be set as appropriate heights of the step when getting on the platform and when getting off the platform, respectively.

[0024] According to a preferred aspect, when the loading platform is raised from the state where it is in the first position for a predetermined time or when the loading platform is lowered from the state where it is in the second position for a predetermined time, it is regarded that the loading platform has reached the third position. <>

[0025] According to such an aspect, it is possible to determine whether the loading platform has reached the third position by a simple method of time management.

[0026] According to a preferred aspect, the loading platform lifting device is connected to the control device and further includes a registration operation unit capable of operating to register the third position in the control device.

[0027] According to such an aspect, for example, the third position can be set as a position preferred by the operator according to the height of the operator or the like.

[0028] The vehicle disclosed herein comprises a vehicle body, a cargo bed mounted on the vehicle body, and a cargo bed lifting device as described in any one of the above. With such a vehicle, it is possible to stably climb onto and off the cargo bed of the vehicle using the cargo bed as a stepping stool. [Effects of the Invention]

[0029] According to the present invention, it is possible to stably climb onto and off a loading platform using the loading platform as a stepping stool. [Brief explanation of the drawing]

[0030] [Figure 1] This is a side view of the vehicle. [Figure 2] This is a rear view of the vehicle. [Figure 3] This is a side view showing an enlarged view of the rear of the vehicle. [Figure 4] This is a plan view of the control terminal. [Figure 5] This is a control block diagram for the vehicle. [Figure 6] This is a side view of the vehicle with the tailgate in the intermediate position when raised and in the intermediate position when lowered. [Figure 7] This is a flowchart showing the procedure for loading cargo. [Figure 8] This is a side view of a vehicle equipped with a tailgate lifter and a foot switch. [Figure 9] This is a side view of a vehicle equipped with a tailgate lift and an imaging device. [Figure 10] This is a side view of a vehicle equipped with a tailgate lift and a motion sensor. [Figure 11] This is a side view of a vehicle equipped with a tailgate lifter and a weight sensor. [Figure 12] This is a plan view of an operating terminal that allows the operator to set the intermediate position during upward movement and the intermediate position during downward movement. [Modes for carrying out the invention]

[0031] Embodiments of the present invention will be described below with reference to the drawings. It should be noted that the embodiments described herein are not intended to particularly limit the present invention.

[0032] [Configuration of vehicles with tailgate lifters] Figure 1 is a side view of a vehicle 10 with a tailgate lifter (hereinafter also simply referred to as vehicle 10) according to one embodiment. Figure 2 is a rear view of vehicle 10. As shown in Figure 1, the vehicle 10 according to this embodiment comprises a vehicle body 20, a cargo box 30, a tailgate lifter 40, a control device 100 for controlling the tailgate lifter 40, and an operating terminal 200 for operating the tailgate lifter 40.

[0033] The vehicle body 20 comprises a cab 21 having a driver's seat (not shown) inside, a chassis frame 22 supporting the cab 21, left and right front wheels 23 located at the front of the chassis frame 22, and left and right rear wheels 24 located at the rear of the chassis frame 22.

[0034] The cargo box 30 is mounted on the vehicle body 20. More specifically, the cargo box 30 is mounted on the chassis frame 22. The cargo box 30 is supported by the chassis frame 22 and is located behind the cab 21. The cargo box 30 comprises a floor surface 31 on which cargo is placed and a rear door 32. The rear door 32 is located on the rear of the cargo box 30 and is configured to be openable and closable. As shown in Figure 2, the rear door 32 includes a left door 32L and a right door 32R. The left door 32L rotates on its left end and can be opened until it contacts the left side of the cargo box 30. The right door 32R rotates on its right end and can be opened until it contacts the right side of the cargo box 30. Note that the cargo box 30 is an example of a loading platform for cargo, and the loading platform does not have to be configured as a covered box. The loading platform may be, for example, a platform like the loading platform of a truck, which does not have a rear door and is open at the top.

[0035] The tailgate lifter 40 is mounted on the vehicle body 20. The tailgate lifter 40 is fixed to the chassis frame 22. The tailgate lifter 40 is used to lift and lower cargo during loading and unloading operations. The tailgate lifter 40 is located at the rear of the cargo box 30.

[0036] Figure 3 is an enlarged side view of the rear of the vehicle 10. As shown in Figure 3, the tailgate lifter 40 comprises a bracket 41, a support frame 42, a rear bumper 43, a pair of left and right link arms 44, a tailgate 45, and a drive unit 50 for the link arms 44. The bracket 41 is fixed to the chassis frame 22. The support frame 42 is fixed to the bracket 41. The support frame 42 is a frame formed in a U-shape in plan view. The rear side of the support frame 42 is open. The rear bumper 43 is stretched between the left and right rear ends of the support frame 42.

[0037] A pair of link arms 44 are mounted on a support frame 42 and are configured to rotate vertically. The base ends (front ends) of the link arms 44 are supported by the support frame 42 so as to be able to rotate vertically. The base ends of the pair of link arms 44 are each attached to the left and right sides of the support frame 42. The tip ends (rear ends) of the link arms 44 support the tailgate 45 so as to be able to rotate vertically.

[0038] The drive unit 50 raises and lowers the tailgate 45. Here, the drive unit 50 deploys, retracts, and raises and lowers the tailgate 45. However, the tailgate 45 may also be deployed and retracted manually by an operator. As shown in Figure 3, the drive unit 50 is configured to raise and lower the tailgate 45 while maintaining a nearly horizontal position between a ground-level position P1, which is behind the cargo box 30 and at approximately the same height as the ground, and a raised position P2, which is adjacent to the rear of the cargo box 30 and at approximately the same height as the cargo box 30. In Figure 3, the tailgate 45 in the raised position P2 is shown by a solid line, and the tailgate 45 in the ground-level position P1 is shown by a dashed line. The tailgate 45 is an example of a loading platform on which cargo can be placed during loading and unloading.

[0039] The drive unit 50 here rotates the link arm 44 and the tailgate 45 to extend and retract the tailgate 45, as well as raise and lower it. The drive unit 50 is equipped with a lift cylinder 52 and a tilt cylinder 53 that extend and retract by a hydraulic pump 51 (see Figure 1). When the lift cylinder 52 extends and retracts, the link arm 44 rotates, and the tailgate 45 rises and lowers. When the tilt cylinder 53 extends and retracts, the tailgate 45 rotates to assume a nearly vertical or nearly horizontal position.

[0040] As shown in Figure 1, in the retracted position, the tailgate 45 is in a nearly vertical position and is in contact with the rear of the cargo box 30. When the tailgate 45 is deployed, as shown in Figure 3, the tailgate 45 takes a nearly horizontal position. When the tailgate 45 is lowered to its lowest position in the deployed state, it reaches a contact position P1 that is approximately the same height as the ground. When the tailgate 45, loaded with cargo, is raised to the raised position P2 at the contact position P1, the height of the tailgate 45 becomes approximately the same as the floor surface 31 of the cargo box 30. At this time, the tailgate 45 is adjacent to the rear of the cargo box 30 so that there is no gap between it and the cargo box 30 that would hinder cargo handling. This makes it easy to load cargo, especially cargo loaded on a cart with wheels, into the cargo box 30.

[0041] The operating terminal 200 is a terminal for operating the tailgate lifter 40. In this embodiment, the operating terminal 200 is a remote control that is separated from the vehicle body 20 and connected by a cable. However, the operating terminal 200 may be, for example, buttons provided on the vehicle body 20. In this embodiment, the operating terminal 200 is connected to the control device 100 by a wire, but it may also be connected wirelessly.

[0042] Figure 4 is a plan view of the operating terminal 200. As shown in Figure 4, the operating terminal 200 includes a mode selection unit 210 and an operating unit 220. The mode selection unit 210 and the operating unit 220 are connected to the control device 100.

[0043] As shown in Figure 4, the mode selection unit 210 includes a mode selection switch 211 that can switch the operating mode of the tailgate lifter 40 between normal mode M1 and step mode M2. In this embodiment, there are two selectable modes, but the mode selection unit 210 may be configured to select one mode from three or more modes. The mode selection unit 210 is related to the control of the drive unit 50 and should be configured to select one mode from a plurality of modes, including normal mode M1 and step mode M2.

[0044] As will be explained in more detail later, Step Mode M2 ​​is a mode in which the tailgate 45 is stopped at a predetermined height suitable for use as a stepping stool when a worker uses the tailgate 45 as a stepping stool to climb onto the cargo box 30. Normal Mode M1 is a mode for normal loading operations in which the tailgate 45 can be moved to any position between the ground position P1 and the raised position P2 without any particular restrictions. Situations in which Normal Mode M1 may be used include, for example, when storing or unfolding the tailgate 45, when workers do not climb onto or off the cargo box 30 (for example, when there are two workers, one on the ground and the other on the cargo box 30).

[0045] The operating unit 220 is connected to the control device 100 and operates the drive unit 50 via the control device 100. As shown in Figure 4, the operating unit 220 includes an open / close button 221, an up button 222, and a down button 223. The open / close button 221 is a button for unfolding and retracting the tailgate 45. While the open side of the open / close button 221 is pressed, the tailgate 45 unfolds. That is, the tailgate 45 tilts toward a nearly horizontal position. When the open / close button 221 is released, the tailgate 45 stops. While the closed side of the open / close button 221 is pressed, the tailgate 45 retracts. That is, the tailgate 45 stands up toward a nearly vertical position. When the open / close button 221 is released, the tailgate 45 stops.

[0046] The upper button 222 is a button that raises the deployed tailgate 45. While the upper button 222 is pressed, the tailgate 45 rises. When the upper button 222 is released, the tailgate 45 stops. The lower button 223 is a button that lowers the deployed tailgate 45. While the lower button 223 is pressed, the tailgate 45 lowers. When the lower button 223 is released, the tailgate 45 stops. The upper button 222 and the lower button 223 are buttons that raise and lower the tailgate 45. In this embodiment, the buttons that raise and lower the tailgate 45 are divided into the upper button 222 and the lower button 223, but it may also be a single button that can be operated in multiple directions. The buttons that raise and lower the tailgate 45 do not have to be mechanical buttons, but may be, for example, buttons on a screen such as a touch panel.

[0047] However, when step mode M2 ​​is selected, even if the up button 222 is pressed, the tailgate 45 will stop at a predetermined intermediate position P3 during upward movement (see Figure 6). In this embodiment, the tailgate 45 cannot be moved from the intermediate position P3 during upward movement unless the mode is set to normal mode M1. Also, when step mode M2 ​​is selected, even if the down button 223 is pressed, the tailgate 45 will stop at a predetermined intermediate position P4 during downward movement (see Figure 6). In this embodiment, the tailgate 45 cannot be moved from the intermediate position P4 during downward movement unless the mode is set to normal mode M1. The intermediate positions P3 during upward movement and P4 during downward movement will be described later.

[0048] Figure 5 is a control block diagram of the vehicle 10. As shown in Figure 5, the drive unit 50 is equipped with a motor 51M that drives the hydraulic pump 51. The vehicle 10 is equipped with a battery 11 that drives the motor 51M. The battery 11 is connected to the motor 51M by operating a switch (not shown) provided on the vehicle 10. An upward valve 54 and a downward valve 55 are provided between the hydraulic pump 51 and the lift cylinder 52. An extension valve 56 and a retraction valve 57 are provided between the hydraulic pump 51 and the tilt cylinder 53. The control device 100 is connected to the upward valve 54, the downward valve 55, the extension valve 56, and the retraction valve 57 of the drive unit 50 and controls their operation. When the upward valve 54 is opened, the lift cylinder 52 retracts and the tailgate 45 rises. When the downward valve 55 is opened, the lift cylinder 52 extends and the tailgate 45 lowers. When the deployment valve 56 is opened, the tilt cylinder 53 extends and the tailgate 45 rotates in the deployment direction. When the storage valve 57 is opened, the tilt cylinder 53 retracts and the tailgate 45 rotates in the storage direction. The mode selection switch 211, open / close button 221, up button 222, and down button 223 of the operating terminal 200 are connected to the control device 100.

[0049] As shown in Figure 5, the drive unit 50 includes a downward sensor Sl that detects when the tailgate 45 is in the ground position P1, and an upward sensor Sh that detects when the tailgate 45 is in the raised position P2. The downward sensor Sl and the upward sensor Sh are connected to the control unit 100 and transmit signals to the control unit 100 according to the detection results.

[0050] As shown in Figure 5, the control device 100 includes a mode switching unit 110 that switches modes according to the selection made by the mode selection switch 211, a first control unit 120 that controls the operation of the drive unit 50 in normal mode M1, and a second control unit 130 that controls the operation of the drive unit 50 in step mode M2. When normal mode M1 is selected, the first control unit 120 allows the drive unit 50 to be operated by the operation unit 220 even when the tailgate 45 is in the intermediate position P3 when raised or the intermediate position P4 when lowered. The first control unit 120 allows the tailgate 45 to be moved to any position between the ground position P1 and the raised position P2 without any particular restrictions.

[0051] The second control unit 130 includes a first intermediate position registration unit 131, a second intermediate position registration unit 132, and an intermediate stop control unit 133. The first intermediate position registration unit 131 registers the intermediate position P3 during the rise. The intermediate position P3 during the rise is set between the ground position P1 and the rise position P2. In this embodiment, the first intermediate position registration unit 131 registers the time for raising the tailgate 45. Hereinafter, this predetermined time will also be referred to as the rise time Tu. The intermediate position P3 during the rise is managed by the time Tu for raising the tailgate 45 from the state where the tailgate 45 is at the ground position P1.

[0052] The second intermediate position registration unit 132 has the lowering intermediate position P4 registered. The lowering intermediate position P4 is set between the ground position P1 and the raised position P2, and is different from the raised intermediate position P3. However, the lowering intermediate position P4 may be the same position as the raised intermediate position P3. In this embodiment, the second intermediate position registration unit 132 has the time for lowering the tailgate 45 registered. Hereinafter, this predetermined time will also be called the lowering time Td. The lowering intermediate position P4 is managed by the time Td for lowering the tailgate 45 from the state in the raised position P2.

[0053] The intermediate stop control unit 133 controls the drive unit 50 to stop the tailgate 45 at the intermediate position P3 during upward movement. Figure 6 is a side view of the vehicle 10 with the tailgate 45 in the intermediate position P3 during upward movement and the intermediate position P4 during downward movement. In Figure 6, the tailgate 45 when it is in the intermediate position P3 during upward movement is shown with a solid line. The intermediate stop control unit 133 considers that the tailgate 45 has reached the intermediate position P3 during upward movement when it has been raised for a predetermined upward time Tu from the ground position P1. In this embodiment, when raising the tailgate 45 from the ground position P1 in step mode M2, it is not possible to lower the tailgate 45 midway. However, even in step mode M2, if the up button 222 is not pressed, the tailgate 45 can be stopped midway before it reaches the intermediate position P3 during upward movement. The time counted by the intermediate stop control unit 133 is the cumulative time that the up button 222 has been pressed. When step mode M2 ​​is selected, the intermediate stop control unit 133 stops the tailgate 45 at the intermediate position P3 during raising, even if the upper button 222 of the drive unit 50 is operated by the operation unit 220.

[0054] Similarly, the intermediate stop control unit 133 controls the drive unit 50 to stop the tailgate 45 at the intermediate position P4 during descent. In Figure 6, the tailgate 45 when it is at the intermediate position P4 during descent is shown by a dashed line. In Figure 6, the tailgate 45 when it is at the ground position P1 and the raised position P2 is also shown by a dashed line. The intermediate stop control unit 133 considers that the tailgate 45 has reached the intermediate position P4 during descent when it has descended for a predetermined descent time Td from the state where it is at the raised position P2. In this embodiment, when the tailgate 45 is lowered from the raised position P2 in step mode M2, it is not possible to raise the tailgate 45 midway. However, even in step mode M2, if the down button 223 is stopped from being pressed, the tailgate 45 can be stopped before it reaches the intermediate position P4 during descent. The time counted by the intermediate stop control unit 133 is the cumulative time that the down button 223 has been pressed. When step mode M2 ​​is selected, the intermediate stop control unit 133 stops the tailgate 45 at the intermediate position P4 during descent, even if the lower button 223 of the drive unit 50 is operated by the operation unit 220.

[0055] The intermediate position P3 during ascent and the intermediate position P4 during descent are not particularly limited as long as they are between the grounding position P1 and the ascent position P2. For example, the intermediate position P3 during ascent and the intermediate position P4 during descent may be set at a position that is between one-third and two-thirds of the vertical distance between the grounding position P1 and the ascent position P2, with respect to the grounding position P1. The intermediate position P4 during descent may be lower than the intermediate position P3 during ascent. However, the intermediate position P4 during descent may be higher than the intermediate position P3 during ascent.

[0056] The configuration of the control device 100 is not particularly limited. Each part of the control device 100 may be composed of software or hardware. Each part may be a processor or a circuit. The control device 100 may be configured to include a programmable controller, and hardware such as relays may be controlled by software installed on the programmable controller. The control device 100 may also be hardware composed of relays, timers, etc. The divisions such as the mode switching unit 110, the first control unit 120, and the second control unit 130 are conceptual divisions based on functional blocks, and these functional blocks may share circuits and components.

[0057] [How to use the tailgate lift in step mode] The following describes an example of how to use the tailgate lifter 40 in step mode M2. Figure 7 is a flowchart of the procedure for loading cargo into the cargo box 30. As shown in Figure 7, in step S01 of the cargo loading operation into the cargo box 30, the battery 11 of the vehicle 10 is connected to the motor 51M of the drive unit 50, and the hydraulic pump 51 is turned ON. This makes it possible to operate the tailgate lifter 40. At the beginning of the loading operation, the mode selection switch 211 is set to normal mode M1.

[0058] In step S02, the open / close button 221 on the operating terminal 200 is operated to deploy the tailgate 45 (to a nearly horizontal position). In step S03, the down button 223 is operated to lower the tailgate 45 to the ground position P1. In step S04, the worker loads the cargo onto the tailgate 45.

[0059] In the following step S05, the mode selection switch 211 is operated to set the mode to step mode M2. Step S05 may be performed before step S04. In step S06, the up button 222 is operated to raise the tailgate 45 to the intermediate position P3. The tailgate 45 is forcibly stopped when it reaches the intermediate position P3. In this state, the tailgate 45 cannot be raised or lowered unless the mode is changed to normal mode M1. In step S07, the worker climbs onto the cargo box 30 using the tailgate 45 at the intermediate position P3 as a stepping stone.

[0060] In step S08, the mode selection switch 211 is operated to set the mode to normal mode M1. This allows the tailgate 45 to be raised and lowered freely. In step S09, the up button 222 is operated to raise the tailgate 45 to the raised position P2. This brings the height of the tailgate 45 to approximately match the height of the floor surface 31 of the cargo box 30. In step S10, the worker moves the cargo from the tailgate 45 onto the cargo box 30.

[0061] In the following step S11, the mode selection switch 211 is operated to set the mode back to step mode M2. Step S11 may be performed before step S10. In step S12, the down button 223 is operated to lower the tailgate 45 to the intermediate position P4. The tailgate 45 is forcibly stopped when it reaches the intermediate position P4. In this state, the tailgate 45 cannot be raised or lowered unless the mode is changed to normal mode M1. In step S13, the worker steps down to the ground using the tailgate 45 at the intermediate position P4 as a stepping stone. In step S14, the mode selection switch 211 is operated to set the mode to normal mode M1. This allows the tailgate 45 to be raised and lowered freely.

[0062] Although not shown in the diagram, if loading of cargo is completed by step S14, the door 32 of the cargo box 30 is closed, the tailgate 45 is raised to the raised position P2, and then the tailgate 45 is raised and stored. If loading of cargo is not completed by step S14, the tailgate 45 is lowered to the ground position P1, and then the same process as in steps S04 to S14 is repeated.

[0063] [Effects of the Embodiment] The following describes the effects and advantages that the vehicle 10 with a tailgate lifter according to this embodiment can provide.

[0064] The vehicle 10 with a tailgate lifter according to this embodiment comprises a vehicle body 20, a cargo box 30 mounted on the vehicle body 20, and a tailgate lifter 40. The tailgate lifter 40 is a cargo platform lifting device mounted on the vehicle 10 that is used for loading and unloading cargo by raising and lowering between the ground and the floor surface 31 of the cargo box 30, and comprises a tailgate 45 that rises and lowers in a substantially horizontal position, a drive unit 50 that raises and lowers the tailgate 45, and a control device 100 that controls the drive unit 50. The control device 100 includes an intermediate stop control unit 133 that stops the tailgate 45 at a preset intermediate position P3 during raising and an intermediate position P4 during lowering, between a ground contact position P1 which is substantially the same height as the ground and a raised position P2 which is substantially the same height as the floor surface 31 of the cargo box 30.

[0065] With such a vehicle 10, the tailgate 45 can be stopped at a predetermined intermediate position P3 when raised or an intermediate position P4 when lowered. As described in the explanation of the cargo loading operation, during cargo loading, it is possible to use the tailgate 45 as a stepping stool to climb up and down to the cargo box 30. By setting the height of the tailgate 45 used as a stepping stool to the intermediate position P3 when raised or the intermediate position P4 when lowered, it is possible to prevent the height of the tailgate 45 from changing each time the operation is performed. This makes it possible to climb up and down to the cargo box 30 using the tailgate 45 as a stepping stool in a stable manner.

[0066] Raising or lowering the tailgate 45 while a worker is standing on it is undesirable because there is a risk of the worker falling from the tailgate 45 or being caught in the load if the cargo on the tailgate 45 shifts. On the other hand, in vehicles 10 where the cargo box 30 is located at a high position, it is not easy for a worker to climb onto the cargo box 30. Therefore, the tailgate 45 is used as a stepping stone to climb onto and off the cargo box 30.

[0067] In the process of climbing onto the cargo box 30 using the tailgate 45 as a stepping stool, there is often cargo on the tailgate 45. Therefore, the space on the tailgate 45 where the worker can place their feet is small. If the height of the tailgate 45 varies in this situation, the likelihood of the worker tripping increases. If the worker trips, there is a risk of the cargo on the tailgate 45 falling over. According to the vehicle 10 of this embodiment, the height of the tailgate 45 used as a stepping stool is always the same and is set appropriately, so the likelihood of the worker tripping can be reduced.

[0068] In the process of descending from a cargo box 30 using the tailgate 45 as a stepping stool, the worker is often on the cargo box 30 when the tailgate 45 is being lowered. Because the tailgate 45 cannot be seen from the side from the cargo box 30, it is difficult to judge the height of the tailgate 45. As a result, the height of the tailgate 45 is more likely to be set to an inappropriate height for use as a stepping stool. If the height of the tailgate 45 is set to an inappropriate height for use as a stepping stool, the likelihood of the worker tripping increases. According to the vehicle 10 of this embodiment, it is possible to prevent the height of the tailgate 45 from being set to an inappropriate height for use as a stepping stool.

[0069] In a vehicle equipped with a tailgate lifter 40 that raises and lowers the tailgate 45 by rotating a link arm 44, as in the vehicle 10 according to this embodiment, a gap is created between the front end of the tailgate 45 and the cargo box 30 when the tailgate 45 is below the raised position P2. Therefore, if the height of the tailgate 45 is inappropriate, the gap between the tailgate 45 and the cargo box 30 may become too large. A gap that is too large between the tailgate 45 and the cargo box 30 can cause workers to trip.

[0070] The tailgate lifter 40 according to this embodiment further comprises an operating unit 220 and a mode selection unit 210. The operating unit 220 is connected to a control device 100 and operates the drive unit 50 via the control device 100. The mode selection unit 210 is connected to the control device 100 and is configured to control the drive unit 50 and to select one mode from a plurality of modes, including a normal mode M1 and a step mode M2. When normal mode M1 is selected, the control device 100 allows the operation of the drive unit 50 by the operating unit 220 even when the tailgate 45 is in an intermediate position P3 when raised or an intermediate position P4 when lowered. When step mode M2 ​​is selected, the intermediate stop control unit 133 stops the tailgate 45 at the intermediate position P3 when raised or the intermediate position P4 when lowered, even when the drive unit 50 is being operated by the operating unit 220.

[0071] With this configuration, after the tailgate 45 stops at the intermediate position P3 during raising or the intermediate position P4 during lowering in step mode M2, the tailgate 45 cannot be raised or lowered unless the mode is changed to normal mode M1. Therefore, it is possible to prevent the tailgate 45 from being moved from the intermediate position P3 during raising or the intermediate position P4 during lowering due to an operating error of the operating terminal 200 or the like.

[0072] In this embodiment, the intermediate stop control unit 133 stops the tailgate 45 at an intermediate position P3 when raising the tailgate 45 from the ground position P1, and stops the tailgate 45 at an intermediate position P4 when lowering the tailgate 45 from the raised position P2, which is a different position from the intermediate position P3 when raising and is located between the ground position P1 and the raised position P2. With this configuration, the intermediate position P3 when raising, which is mainly used when climbing onto the cargo box 30, and the intermediate position P4 when lowering, which is mainly used when descending from the cargo box 30, can be set to appropriate heights for stepping onto and descending, respectively. The appropriate height for stepping onto the cargo box 30 and the appropriate height for stepping off the cargo box 30 may be different heights.

[0073] In this embodiment, the intermediate stop control unit 133 considers that the tailgate 45 has reached the intermediate position P3 when it has risen for a predetermined time Tu from the state in the ground position P1. With this configuration, it is possible to determine whether the tailgate 45 has reached the intermediate position P3 when it has risen using a simple method of time management. Similarly, in this embodiment, the intermediate stop control unit 133 considers that the tailgate 45 has reached the intermediate position P4 when it has descended for a predetermined time Td from the state in the raised position P2. The effect is the same as in the case of the intermediate position P3 when it has risen.

[0074] [Other embodiments] A preferred embodiment of the present invention has been described above. However, the above-described embodiment is merely an example, and the present invention can be implemented in various other forms.

[0075] For example, the intermediate stop control unit 133 may be configured to disable operation of the drive unit 50 by the operating unit 220 after stopping the tailgate 45 at the intermediate position P3 during upward movement or the intermediate position P4 during downward movement, until predetermined conditions are met. The conditions for enabling operation of the drive unit 50 by the operating unit 220 again after stopping the tailgate 45 at the intermediate position P3 during upward movement or the intermediate position P4 during downward movement may be conditions other than a change in mode.

[0076] The predetermined conditions for enabling the operation of the drive unit 50 again may include, for example, the cessation of pressing the buttons for raising or lowering the tailgate 45 (here, the upper button 222 and the lower button 223) after the tailgate 45 has stopped at the intermediate position P3 when raised or the intermediate position P4 when lowered. With this configuration, after pressing the upper button 222 and the lower button 223 to stop the tailgate 45 at the intermediate position P3 when raised or the intermediate position P4 when lowered, if the operation is stopped, the next operation of the upper button 222 or the lower button 223 becomes valid. Therefore, it becomes very easy to restart the drive unit 50.

[0077] The predetermined conditions for enabling the operation of the drive unit 50 again may be that the worker has stepped onto the tailgate 45 and then moved away from it (either by using the tailgate 45 as a stepping stool and then climbing onto the cargo box 30 or descending to the ground). Figure 8 is a side view of another preferred vehicle 10 with a tailgate lifter. In the following description of several other embodiments, the same reference numerals will be used for components that have the same effects as those in the above-described embodiment. As shown in Figure 8, in one preferred embodiment, the tailgate lifter 40 further includes a foot switch 61 provided on the tailgate 45. The predetermined conditions for enabling the operation of the drive unit 50 again by the operating unit 220 include that the foot switch 61 has been pressed and then released. The foot switch 61 is located in a place that is easily accessible to the worker when using the tailgate 45 as a stepping stool. Here, the foot switch 61 is located at one of the left or right ends of the tailgate 45, specifically at the end where the storage compartment 25 for housing the operating terminal 200 is provided.

[0078] The cargo is generally loaded in the center of the tailgate 45 in the left-right direction. The worker is often on the side of the vehicle body 20 where the storage compartment 25 is located, in order to operate the operation terminal 200. Therefore, the worker can easily place their foot on the end of the tailgate 45 on the side where the storage compartment 25 is located. By placing the foot switch 61 on the end of the tailgate 45 on the side where the storage compartment 25 is located, the worker can easily step on the foot switch 61. Since the foot switch 61 was pressed and then released, it can be inferred that the worker placed their foot on the foot switch 61 and then climbed onto the cargo box 30 or got off the cargo box 30. Therefore, in this embodiment, the condition for enabling the operation of the drive unit 50 again is that the foot switch 61 is pressed and then released.

[0079] Figure 9 is a side view of yet another preferred vehicle 10 with a tailgate lifter. As shown in Figure 9, in this embodiment, the tailgate lifter 40 further comprises an imaging device 62 that images the tailgate 45. The control device 100 includes a person recognition unit 140 that recognizes a person from the image captured by the imaging device 62. A predetermined condition for enabling the operation of the drive unit 50 again includes the determination by the person recognition unit 140 that a person has moved away from the tailgate 45 after getting on it. The person recognition unit 140 performs the determination, for example, by AI (artificial intelligence).

[0080] Figure 10 is a side view of yet another preferred vehicle 10 with a tailgate lifter. As shown in Figure 10, in this embodiment, the tailgate lifter 40 further includes a human presence sensor 63 for detecting a person on the tailgate 45. The human presence sensor 63 is, for example, an infrared sensor that detects infrared radiation emitted by the body heat of a worker. According to the infrared sensor, the worker can be distinguished from cargo because the heated area moves. However, the human presence sensor 63 is not limited to an infrared sensor. The human presence sensor 63 may be, for example, an optical sensor that detects an object on the tailgate 45, more preferably a plurality of optical sensors arranged in a front-to-back or left-to-right direction. After a worker gets onto the tailgate 45 and then leaves the tailgate 45, the optical sensor goes from an object detection state to a non-detection state. This makes it possible to detect that a worker has gotten onto the tailgate 45 and then left the tailgate 45. The control device 100 includes a human recognition unit 150 that acquires the detection result of the human presence sensor 63. The predetermined conditions for enabling the operation of the drive unit 50 again include the determination by the person recognition unit 150 that a person has left the tailgate 45 after getting on it. The person recognition unit 150 performs the determination, for example, using AI.

[0081] Figure 11 is a side view of another preferred vehicle 10 with a tailgate lifter. As shown in Figure 11, in this embodiment, the tailgate lifter 40 further comprises a weight sensor 64 that measures the weight of an object placed on the tailgate 45. The weight sensor 64 is here a pressure sensor that measures the hydraulic pressure applied to the lift cylinder 52. As the weight of the object placed on the tailgate 45 increases or decreases, the hydraulic pressure applied to the lift cylinder 52 also increases or decreases. In many cases, the vehicle 10 is equipped with a pressure sensor that measures the hydraulic pressure applied to the lift cylinder 52. Therefore, it is possible to detect increases or decreases in the weight of an object placed on the tailgate 45 without increasing the number of parts. However, the weight sensor 64 may be, for example, a load cell provided on the tailgate 45. A predetermined condition for enabling the operation of the drive unit 50 again includes the weight measured by the weight sensor 64 having increased and then decreased. The increase and subsequent decrease in weight on the tailgate 45 suggests that the worker either climbed onto the cargo box 30 or descended from the cargo box 30 after leaning their weight on the tailgate 45.

[0082] In the embodiment described above, whether the tailgate 45 reached the intermediate position P3 during upward movement and the intermediate position P4 during downward movement was determined based on the upward movement time and the downward movement time of the tailgate 45, respectively. However, the determination of whether the tailgate 45 has reached the intermediate position P3 during upward movement and the intermediate position P4 during downward movement may be made by other means. For example, the tailgate lifter 40 may be equipped with an angle sensor that measures the inclination angle of the link arm 44 from the horizontal, vertical, or other directions. Based on the inclination angle of the link arm 44, the vertical position of the tailgate 45 can be calculated. Therefore, it is possible to determine whether the tailgate 45 has reached the intermediate position P3 during upward movement and the intermediate position P4 during downward movement based on the measurement of the inclination angle of the link arm 44. More simply, the vehicle 10 may be equipped with a sensor that detects when the tailgate 45 has reached the intermediate position P3 during upward movement and a sensor that detects when the tailgate 45 has reached the intermediate position P4 during downward movement (for example, limit switches, respectively).

[0083] In the embodiment described above, whether the tailgate 45 has reached the intermediate position P3 during upward movement and the intermediate position P4 during downward movement is determined based on the upward movement time and the downward movement time of the tailgate 45, respectively. In step mode M2, it was prohibited to switch to downward movement while the tailgate 45 was moving upward, and to switch to upward movement while it was moving downward. However, even in a configuration where the intermediate position P3 during upward movement and the intermediate position P4 during downward movement are time-controlled, it may be permitted in step mode M2 ​​to switch to downward movement while the tailgate 45 is moving upward, and to switch to upward movement while it is moving downward. In that case, for example, the timer count may increase while the tailgate 45 is moving upward, and decrease while it is moving downward (in the case of upward movement; the reverse operation in the case of downward movement).

[0084] In the embodiment described above, the intermediate position P3 during upward movement and the intermediate position P4 during downward movement were predetermined during the design of the vehicle 10. However, at least one of the intermediate position P3 during upward movement and the intermediate position P4 during downward movement may be set by the operator. Figure 12 is a plan view of an operation terminal 200 that allows the operator to set the intermediate position P3 during upward movement and the intermediate position P4 during downward movement. As shown in Figure 12, the tailgate lifter 40 according to this embodiment further includes a registration operation unit 230 that is connected to a control device 100 (see Figure 5) and allows the operator to register the intermediate position P3 during upward movement and the intermediate position P4 during downward movement with the control device 100. The registration operation unit 230 is provided on the operation terminal 200. However, the registration operation unit 230 may be provided in another location, for example, in the storage unit 25 of the operation terminal 200.

[0085] As shown in Figure 12, in a preferred example, the registration operation unit 230 includes a mode selection switch 231 that can select registration mode M3, a registration button 232 for the intermediate position P3 when raised, and a registration button 233 for the intermediate position P4 when lowered. In a preferred example, with the mode set to registration mode M3, the operator operates the operation unit 220 to set the height of the tailgate 45 to the operator's preferred height. When the registration button 232 for the intermediate position P3 when raised is pressed while the tailgate 45 is at the preferred height, the height of the tailgate 45 at that time is registered as the intermediate position P3 when raised. When the registration button 233 for the intermediate position P4 when lowered is pressed while the tailgate 45 is at the preferred height, the height of the tailgate 45 at that time is registered as the intermediate position P4 when lowered. The vertical position of the tailgate 45 may be determined, for example, based on the measurement of an angle sensor that measures the inclination angle of the link arm 44.

[0086] With this configuration, the intermediate position P3 during upward movement and the intermediate position P4 during downward movement can be set to a position preferred by the worker, for example, based on their own height. The intermediate position P3 during upward movement and the intermediate position P4 during downward movement may be the same position, in which case only one registration button may be required. One of the intermediate positions P3 during upward movement and the intermediate position P4 during downward movement may be predetermined and not changeable by the worker. The button configuration of the registration operation unit 230 is not limited to the above. For example, it is possible to reduce the number of buttons on the registration operation unit 230 by using long-pressing buttons or pressing multiple buttons simultaneously.

[0087] In the embodiment described above, the basic mode was set to a mode in which the tailgate 45 can be moved without any particular restriction to any position between the ground position P1 and the raised position P2 (normal mode M1). However, a mode in which the tailgate 45 stops at the intermediate position P3 when raised or the intermediate position P4 when lowered (step mode M2 ​​in the embodiment described above) may be set to the default mode. In that case, the mode may switch from step mode to normal mode (lifting mode) when certain conditions are met. The above-mentioned predetermined conditions may include, for example, operating a switch to change the mode to lifting mode. The tailgate lifter 40 may be configured such that, for example, when the tailgate 45 passes through the intermediate position P3 when raised and the intermediate position P4 when lowered in lifting mode (or stops at the intermediate position P3 when raised and the intermediate position P4 when lowered), the mode returns to step mode.

[0088] In the embodiment described above, the vehicle 10 was equipped with a tailgate lifter 40 that raised and lowered the tailgate 45 by rotating a link arm 44. However, the type of tailgate lifter 40 is not limited to this. The tailgate lifter 40 may be, for example, a type of tailgate lifter that uses a lift cylinder to pull the tailgate 45 upright. The tailgate lifter 40 may be, for example, a type of tailgate lifter that stores the tailgate 45 below the chassis frame 22, rather than storing the tailgate 45 upright. The type of tailgate lifter 40 is not particularly limited.

[0089] Unless otherwise specified, the embodiments are not limiting to the present invention. Furthermore, the embodiments of the invention disclosed herein can be modified in various ways. Unless any particular problems arise, each component and each process mentioned herein can be omitted or combined as appropriate. [Explanation of symbols]

[0090] 10 vehicles 20 car bodies 30 Cargo boxes (cargo beds) 40. Tailgate Lifter (Loading Platform Lifting Device) 45 Tailgate (loading platform) 50 Drive unit 61 Footswitch 62 Imaging device 63 motion sensors 64 Weight Sensors 100 Control device 110 Mode switching section 133 Intermediate Stop Control Unit (Intermediate Stop Section) 140 person recognition department 150 people recognition department 200 Operating terminals 210 Mode Selection Section 220 Operation section 222 Up button (button) 223 Down button (button) 230 Registration Operation Unit M1 Normal Mode (Mode 1) M2 Step Mode (Second Mode) M3 Registration Mode P1 Grounding position (1st position) P2 Ascending position (second position) P3: Intermediate position during ascent (3rd position) P4 Intermediate position when descending (4th position)

Claims

1. A loading platform lifting device mounted on a vehicle having a loading platform, which is used for loading and unloading cargo by raising and lowering between the ground and the floor of the loading platform, A loading platform that moves up and down in a nearly horizontal position, A drive device for raising and lowering the aforementioned loading platform, The system comprises a control device for controlling the aforementioned drive device, The control device includes an intermediate stop unit that stops the loading platform at a third position predetermined between a first position which is approximately the same height as the ground and a second position which is approximately the same height as the floor surface of the loading platform. Loading platform lifting device.

2. An operating unit connected to the control device and operating the drive device via the control device, The system further comprises a mode selection unit connected to the control device, which is involved in the control of the drive device and can select one mode from a plurality of modes including a first mode and a second mode, The control device is configured such that, when the first mode is selected, the drive unit can be operated by the operating unit even when the loading platform is in the third position. When the second mode is selected, the intermediate stop unit stops the load receiving platform at the third position, even if the drive unit is being operated by the operation unit. The loading platform lifting device according to claim 1.

3. The control device is connected to the control device and further comprises an operating unit that operates the drive device via the control device, The intermediate stop unit, after stopping the loading platform at the third position, disables operation of the drive unit by the operating unit until predetermined conditions are met. The loading platform lifting device according to claim 1.

4. The control unit is equipped with a button for raising and lowering the loading platform. The aforementioned predetermined conditions include the cessation of pressing the button after the loading platform has stopped at the third position. The loading platform lifting device according to claim 3.

5. The aforementioned loading platform is further equipped with a foot switch, The aforementioned predetermined conditions include the foot switch being released after being pressed, The loading platform lifting device according to claim 3.

6. The system further includes an imaging device for imaging the surface of the loading platform, The control device includes a person recognition unit that recognizes a person from an image captured by the imaging device, The aforementioned predetermined conditions include the determination by the person recognition unit that a person has moved away from the loading platform after getting onto it. The loading platform lifting device according to claim 3.

7. The aforementioned loading platform is further equipped with a motion sensor that detects people, The control device includes a human recognition unit that acquires the detection result of the human presence sensor, The aforementioned predetermined conditions include the determination by the person recognition unit that a person has moved away from the loading platform after getting onto it. The loading platform lifting device according to claim 3.

8. The load receiving platform is further equipped with a weight sensor for measuring the weight of an object placed on it. The aforementioned predetermined conditions include the weight measured by the weight sensor increasing and then decreasing, The loading platform lifting device according to claim 3.

9. The intermediate stopping unit stops the loading platform at the third position when raising it from the first position, and stops the loading platform at a fourth position, which is different from the third position and between the first and second positions, when lowering it from the second position. The loading platform lifting device according to claim 1.

10. The intermediate stopping unit deems that the loading platform has reached the third position when it has been raised for a predetermined time from the first position, or when it has been lowered for a predetermined time from the second position. The loading platform lifting device according to claim 1.

11. The system further includes a registration operation unit connected to the control device, which is capable of registering the third position to the control device. The loading platform lifting device according to claim 1.

12. The car body and, A cargo bed mounted on the aforementioned vehicle body, A vehicle comprising a loading platform lifting device according to any one of claims 1 to 11.

Images