JP7631152B2 - Loading vehicle - Google Patents

Description

The present invention relates to a cargo handling vehicle that can tilt a cargo box relative to the chassis.

Loading vehicles that can tilt a cargo box relative to the chassis include so-called container loading vehicles and dump trucks. Some of these types of loading vehicles are equipped with an inclination sensor on the arm that tilts the cargo box (see Patent Document 1, etc.). The loading vehicle in this document uses an inclination sensor that detects an angle based on the direction of gravity, so the inclination angle of the arm relative to the horizontal plane is detected. In this case, even if the angle of the arm relative to the chassis is the same, the detection value of the inclination sensor will differ depending on the angle of the chassis (i.e. the angle of the ground on which the chassis touches the ground).

Therefore, in this document, a tilt sensor that detects the tilt angle based on the direction of gravity is also installed on the chassis, and the difference between the detection values of these two tilt sensors is calculated as the angle of the arm relative to the chassis.

JP 2016-215916 A

In Patent Document 1, inclination sensors are provided on both the arm and the chassis to calculate the relative inclination angle of the arm to the chassis. Each time the loading vehicle moves to load or unload a container, the relative inclination angle of the arm to the chassis is calculated from the detection values of the inclination sensors on the chassis and arm, and inclination sensors are required on both the chassis and the arm. This leads to higher component costs and more complicated wiring layouts.

The object of the present invention is to provide a cargo handling vehicle that can grasp the inclination angle of the chassis and calculate the relative inclination angle of the arm to the chassis while minimizing the number of inclination sensors.

To achieve the above object, the present invention provides a loading vehicle that includes a chassis, an arm that supports a cargo box relative to the chassis, an inclination sensor that detects the angle of the arm based on the direction of gravity, a detector that detects whether the angle of the arm relative to the chassis is a predetermined angle, and a control device that calculates the relative inclination angle of the arm relative to the chassis, and the control device stores the output of the inclination sensor before the arm, which is at the predetermined angle relative to the chassis, starts to tilt as the chassis inclination angle based on the outputs of the inclination sensor and the detector, and calculates the relative inclination angle based on the output of the inclination sensor and the chassis inclination angle after the arm starts to tilt.

The present invention makes it possible to grasp the inclination angle of the chassis while minimizing the number of inclination sensors, and calculate the relative inclination angle of the arm with respect to the chassis.

FIG. 1 is a side view of a loading vehicle according to an embodiment of the present invention; FIG. 1 is a plan view of a loading vehicle according to an embodiment of the present invention; FIG. 1 is a rear view of a loading vehicle according to an embodiment of the present invention; FIG. 2 is a perspective view of a special unit provided on the loading vehicle of FIG. FIG. 1 is a schematic diagram of a drive system provided in a loading vehicle according to an embodiment of the present invention. Illustration of dump inclination angle Arm rotation angle diagram FIG. 2 is a diagram showing the loading operation of a standard container by the loading vehicle of FIG. 1. FIG. 2 is a diagram showing the loading operation of a standard container by the loading vehicle of FIG. 1. FIG. 2 is a diagram showing the loading operation of a standard container by the loading vehicle of FIG. 1. FIG. 2 is a diagram showing the loading operation of a standard container by the loading vehicle of FIG. 1. FIG. 2 is a diagram showing the loading operation of a standard container by the loading vehicle of FIG. 1. 2 is a flowchart showing a procedure for calculating the relative inclination angle of the arm with respect to the vehicle chassis by the control device provided in the loading vehicle of FIG. 1. FIG. 1 is a side view of a loading vehicle according to a modified example of the present invention. FIG. 1 is a plan view of a loading vehicle according to a modified example of the present invention; FIG. 1 is a rear view of a loading vehicle according to a modified example of the present invention. FIG. 15 is a diagram showing a state of dumping operation by the loading vehicle of FIG. 14 . FIG. 15 is a diagram showing the loading operation of the special container by the loading vehicle of FIG. 14 . FIG. 15 is a diagram showing the loading operation of the special container by the loading vehicle of FIG. 14 . FIG. 15 is a diagram showing the loading operation of the special container by the loading vehicle of FIG. 14 .

An embodiment of the present invention will be described below with reference to the drawings.

-Loading vehicle-
Fig. 1 is a side view of a loading vehicle according to an embodiment of the present invention, Fig. 2 is a plan view, and Fig. 3 is a rear view. In this specification, the left, right, bottom, and top in Fig. 2 refer to the front, back, left, and right of the loading vehicle. Furthermore, loading and unloading work for loading and unloading containers (packing boxes) onto and from the chassis 3 of the vehicle 1 and dumping work are collectively referred to as "loading and unloading work".

The loading vehicle shown in Figures 1 to 3 is composed of a vehicle 1 and a specially equipped unit 10. The vehicle 1 is a self-propelled vehicle, and has a driver's cab 2 at the front and a chassis 3 behind the driver's cab 2.

Figure 4 is a perspective view of the special equipment unit 10. In this figure, unlike Figures 1 to 3, in order to make the configuration easier to see, the special equipment unit 10 is shown in a dump position with the dump frame A2 (described later) raised. The special equipment unit 10 is a unit attached to the top of the chassis 3 for loading and unloading operations, and as shown in Figures 1 to 4, it is equipped with a loading device A, a container guide device B, a locking device C, a jack D, an adapter E, etc.

The container guide device B is a device that supports and guides a standard container X (Fig. 10, etc.) that is the subject of loading and unloading operations using the adapter E, and is provided at the rear of the special unit 10. The lock device C is a device that secures a loaded special container (Fig. 18) when it is loaded. The jack D is a device that prevents the rear of the chassis 3 from sinking during loading and unloading operations. The adapter E is a type of attachment that is attached to the standard container X in order to load it onto the chassis 3. When not in use, this adapter E is fixed to a support post A11 provided at the front of the base frame A1. The configuration of the loading device A will be explained next.

- Cargo handling equipment -
The loading and unloading device A is a device for lifting containers onto the vehicle chassis 3 and lowering them from the vehicle chassis 3, and is composed of a base frame A1, a dump frame A2 (Figure 2, etc.), a loading and unloading arm A3, a drive unit A4, and a guide roller A5.

Base Frame The base frame A1 is a basic structure of the loading/unloading apparatus A. The base frame A1 is configured in a horizontal rectangular shape, extends in the front-rear direction, and is fixed to the upper part of the chassis 3 by overlapping therewith.

Dump Frame The dump frame A2 is a frame for tilting up a loaded container on the vehicle chassis 3 in order to dump the contents of the container. The dump frame A2 is disposed at the rear of the base frame A1 and is rotatably connected to the rear end of the base frame A1 via a shaft A6 extending in the left-right direction (vehicle width direction). The front-to-rear length of the dump frame A2 is shorter than the front-to-rear length of the base frame A1.

Loading/Unloading Arm The loading/unloading arm A3 is an arm for loading/unloading a container, and supports the container on the vehicle chassis 3. The loading/unloading arm A3 includes a base arm A7 and a hook arm A8. The base arm A7 is a cylindrical arm that extends linearly in the front-rear direction, is rotatably connected to the front (tip) of the dump frame A2 via a shaft A9 that extends in the left-right direction, and rotates in the front-rear direction on the vehicle chassis 3. The hook arm A8 is an L-shaped arm whose rear part extends in the front-rear direction and whose front part stands up, and whose rear part is slidably inserted into the base arm A7. A hook F that can be hung on a standard container X (FIG. 10, etc.) is provided at the tip (upper end) of the hook arm A8.

Standard container X is a container manufactured in accordance with standards such as ISO standards, for example a marine container. Standard container X is not manufactured to be loaded and unloaded by cargo handling vehicles, and is usually loaded onto a means of transportation such as a ship, trailer, or railway using separate cargo handling machinery such as a crane or forklift. Standard container X, which is formed in a rectangular parallelepiped shape, has corner fittings with recesses on each face at each of the eight corners.

Although not specifically shown, the upper part of the upright part of the hook arm A8 may be configured to be freely rotated back and forth relative to the lower part by a hydraulic cylinder (not shown), and the height and fore-aft position of the hook F may be changed on this rotation path.

In addition, in this embodiment, the hook arm A8 slides relative to the base arm A7, but the hook arm A8 may rotate instead of sliding relative to the base arm A7. The loading/unloading arm A3 may also be configured as an integrated L-shaped arm without being divided into the base arm A7 and the hook arm A8.

Driving unit The driving unit A4 drives the loading/unloading arm A3. The driving unit A4 includes a pair of lift cylinders A10 on the left and right sides that rotate the base arm A7, a slide cylinder A12 (FIG. 5) that slides the hook arm A8 relative to the base arm A7, and a hydraulic circuit G1 (FIG. 5) that drives these cylinders. The lift cylinder A10 and the slide cylinder A12 are both hydraulic cylinders. The base end of the lift cylinder A10 is connected to the base frame A1, and the tip of the lift cylinder A10 is connected to the rear of the base arm A7 so that it can rotate freely. The slide cylinder A12 is housed inside the base arm A7, and the base end is connected to the base arm A7 and the tip is connected to the hook arm A8.

Guide rollers The above-mentioned guide rollers A5 are rollers for guiding a special container (FIG. 18), and are provided on both the left and right ends of the shaft A6 supporting the dump frame A2. A "special container" is a container manufactured assuming loading and unloading operations by a cargo handling vehicle, and is configured so that loading and unloading operations can be performed without using an adapter E. These guide rollers A5 are positioned lower than the guide surface of the standard container X by the container guiding device B (the underside of the loaded standard container X), so as not to interfere with the standard container X, including during loading and unloading operations.

In the loading vehicle of this embodiment, during loading and unloading operations, only the loading and unloading arm A3 rotates back and forth while the dump frame A2 remains in a horizontal position, and during dumping operations, the dump frame A2 rotates integrally with the loading and unloading arm A3. To enable this operation, a dump lock device (not shown) is provided that locks and unlocks the loading and unloading arm A3 relative to the dump frame A2.

The dump truck lock device consists of a lock pin and a lock hook that can be engaged and disengaged with the lock pin. The lock pin is provided at the tip of the dump truck frame A2, and the lock hook is rotatably provided on both sides of the base arm A7 of the loading/unloading arm A3. The lock hook is engaged and disengaged with the lock pin by using the sliding movement of the hook arm A8 relative to the base arm A7. For example, the lock hook is subjected to a force from a spring or the like in the direction in which it is engaged with the lock pin, and when the hook arm A8 slides to the rear end, the hook arm A8 pushes an operating rod, disengaging the lock hook from the lock pin.

In this case, when the hook arm A8 retreats to near the rear end, the loading arm A3 is unlocked from the dump frame A2, and the lift cylinder A10 expands and contracts, causing the loading arm A3 to rotate back and forth relative to the dump frame A2. Conversely, when the hook arm A8 advances, the loading arm A3 is locked to the dump frame A2, and when the lift cylinder A10 expands and contracts in this state, the dump frame A2 tilts up and down together with the loading arm A3. The configuration of this type of dump lock device is described in Patent Publication No. 5284541, etc.

- Drive system -
Fig. 5 is a schematic diagram of a drive system provided in a cargo handling vehicle according to this embodiment of the present invention. As shown in the figure, the cargo handling vehicle is equipped with a hydraulic circuit G1 for driving the lift cylinder A10 and the slide cylinder A12, a control device G2, and various sensors. The control device G2 will be described later.

Hydraulic circuit The hydraulic circuit G1 includes a hydraulic pump and a control valve (e.g., an electromagnetically driven directional control valve), etc. For example, the hydraulic pump is driven by engine power taken out by a PTO (Power Take Off), and the lift cylinder A10 and the slide cylinder A12 are extended and retracted by the oil discharged from the hydraulic pump being supplied via the control valve.

Sensors As shown in FIG. 5, the cargo handling vehicle is provided with an inclination sensor S1 and a lift contraction sensor S2.

The tilt sensor S1 is a sensor that detects the tilt angle of the loading/unloading arm A3 based on the direction of gravity (e.g., the tilt angle with respect to a horizontal plane), and is provided on the loading/unloading arm A3. For example, a gyroscope or an IMU (inertial measurement unit) can be used for this tilt sensor S1. In addition, a pendulum-type or float-type tilt sensor (a sensor that detects the tilt with respect to a hanging weight or the liquid surface) or an acceleration sensor can be used as the tilt sensor S1. The tilt sensor S1 detects the angle of the loading/unloading arm A3 based on the direction of gravity and outputs it to the control device G2 (Figure 5). The installation location of the tilt sensor S1 on the loading/unloading arm A3 may be either the base arm A7 or the hook arm A8, but it is preferable to install the tilt sensor S1 on, for example, the outer wall surface of the base arm A7 that constitutes the outer cylinder, or the outer wall surface of the front part of the hook arm A8 that is always exposed to the base arm A7.

The lift retraction sensor S2 is a detector that detects when the loading/unloading arm A3 is at a predetermined angle relative to the chassis 3. For example, a sensor (such as a limit switch) that detects when the lift cylinder A10 is at a predetermined length (in this embodiment, the most retracted state, i.e., when the loading/unloading arm A3 is at 0 degrees relative to the chassis 3) can be used for this lift retraction sensor S2. To detect when the loading/unloading arm A3 is at a predetermined angle relative to the chassis 3, a goniometer that detects the angle of the loading/unloading arm A3 relative to the chassis 3 can also be used.

The control device G2 is a type of on-board computer, and includes, for example, a CPU and a memory. The control device G2 outputs a command signal to drive the control valve in response to the operation of the operating device H, and controls the operation of the lift cylinder A10 and the slide cylinder A12 by switching the supply direction of the hydraulic oil with the control valve, thereby controlling the operation of the loading/unloading arm A3.

The memory of the control device G2 stores a program for controlling the loading/unloading arm A3, as well as a program for calculating the relative inclination angle of the loading/unloading arm A3 with respect to the chassis 3. In addition to the output signals of the tilt sensor S1 and lift contraction sensor S2 described above, the control device G2 receives operation signals from an operating device H such as a remote control, and an on/off signal from the PTO switch P. The PTO switch P is a switch that turns the PTO on and off. When the PTO is turned on with the PTO switch P, engine power is transmitted to the hydraulic circuit G1, and when the PTO is turned off with the PTO switch P, the transmission of engine power to the hydraulic circuit G1 is cut off. The tilt sensor (a sensor that measures an angle based on the direction of gravity) that the control device G2 uses as the basis for calculating the relative inclination angle of the loading/unloading arm A3 is only the single tilt sensor S1. In other words, the chassis 3 is not provided with an inclination sensor such as an IMU.

The relative inclination angle of the loading/unloading arm A3 with respect to the chassis 3 includes the dump angle θtilt (FIG. 6) and the arm swing angle θarm (FIG. 7). The dump angle θtilt is the relative inclination angle of the loading/unloading arm A3 with respect to the chassis 3 when the dump frame A2 and the loading/unloading arm A3 tilt together (see also FIG. 4). The arm swing angle θarm is the relative inclination angle of the loading/unloading arm A3 with respect to the chassis 3 when the loading/unloading arm A3 bends and tilts with respect to the dump frame A2 (see also FIG. 9). In this embodiment, the dump angle θtilt and the arm swing angle θarm are calculated based on the signal from the operating device H (depending on whether the operating signal is an operating signal for loading/unloading work, which will be described later, or an operating signal for dumping work).

- Loading and unloading operations -
When loading a standard container X onto the vehicle frame 3, the loading vehicle is stopped at a predetermined position in front of the standard container X, and the adapter E and the support post A11 are manually disconnected from each other in the state shown in Figs. 1-3. Next, the jack D is lowered, and the hook arm A8 is advanced by a predetermined operation using the operating device H, and the hook F is hooked onto the adapter E as shown in Fig. 8. Once the hook F is hooked onto the adapter E, the hook arm A8 is retracted together with the adapter E, and the unloading button for unloading work is operated using the operating device H. This releases the lock of the dump lock device described above, and the lift cylinder A10 extends as shown in Fig. 9, causing the loading and unloading arm A3 to rotate backward. The adapter E thus brought out to the rear of the vehicle is then attached to the front of the standard container X as shown in Fig. 10.

After the installation of the adapter E is completed, the lifting button for loading and unloading is operated on the operating device H to rotate the loading and unloading arm A3 forward, and the standard container X is lifted onto the vehicle frame 3 as shown in FIG. 11. As the loading and unloading arm A3 moves, the front side of the standard container X is lifted with the lower rear end as a fulcrum, and the loading and unloading arm A3 further rotates forward, bringing the vehicle and the standard container X relatively closer to each other. At this time, since the standard container X is heavy and has no rollers on its lower part, the vehicle moves backward and enters the underside of the standard container X, and the left and right sides of the underside of the standard container X are supported by the container guide device B. After that, the loading and unloading arm A3 further rotates forward, and the standard container X is lifted to the top of the vehicle frame 3 while being guided by the container guide device B. When the loading and unloading arm A3 is horizontally lowered, the hook arm A8 is advanced, and the adapter E is placed on the stand of the support post A11 as shown in FIG. 12. Finally, the standard container X is secured to the container guiding device B using the locking device provided on the container guiding device B, completing the loading operation of the standard container X.

The unloading operation of the standard container X from the vehicle frame 3 can be carried out by reversing the steps of the container loading operation described above.

The memory of the control device G2 stores the deceleration start angle during loading and unloading operations. The deceleration start angle during loading and unloading operations includes a first value set slightly smaller than the arm rotation angle θarm at which the container touches the ground, and a second value set slightly larger than the arm rotation angle θarm when the container lands on the vehicle chassis 3. During the arm rotation (container unloading) operation, if the arm rotation angle θarm is equal to or greater than the first value, the control device G2 decelerates the arm rotation speed to mitigate the impact when the container lands on the ground. Conversely, during the arm rotation (container loading) operation, if the arm rotation angle θarm is equal to or less than the second value, the control device G2 decelerates the arm rotation speed to mitigate the impact when the container lands on the vehicle chassis 3.

-Dumping work-
Also, when performing a dumping operation, for example, by operating the dump lift button for the dumping operation with the operating device H, the dump lock device described above is locked, and the lift cylinder A10 extends as shown in Fig. 4, and the dump frame A2 together with the loading/unloading arm A3 rises backward. This allows the contents of the container to be dumped. After that, by operating the dump lowering button for the dumping operation with the operating device H, the lift cylinder A10 contracts, and the dump frame A2 together with the loading/unloading arm A3 falls as shown in Fig. 8.

The memory of the control device G2 stores the deceleration start angle during dumping. The deceleration start angle during dumping includes a third value set slightly smaller than the dump angle θtilt (maximum value of θtilt) during full dumping, and a fourth value set slightly larger than the dump angle θtilt when the container lands on the chassis 3. During dumping (raising) operation, if the dump angle θtilt is equal to or greater than the third value, the control device G2 decelerates the tilt speed of the container to mitigate the impact when it reaches the stroke end of the lift cylinder A10. Conversely, during dumping (lowering) operation, if the dump angle θtilt is equal to or less than the fourth value, the control device G2 decelerates the tilt speed of the container to mitigate the impact when the container lands.

- Calculation of relative inclination angle of arm -
Fig. 13 is a flow chart showing the procedure for calculating the relative inclination angle of the loading/unloading arm A3 with respect to the chassis 3 by the control device G2. When energized, the control device G2 repeatedly executes the flow of Fig. 13 in a short cycle time (e.g., 0.1 s). Fig. 13 illustrates an example in which the arm swing angle θarm (Fig. 7) is calculated as the relative inclination angle of the loading/unloading arm A3, but the calculation procedure for the dump angle θtilt is similar.

・START
When the flow of FIG. 13 is started, the control device G2 first receives signals from the tilt sensor S1, the lift contraction sensor S2, the operation device H and the PTO switch P, which are input in real time, and records them in memory.

Step S01
In the next step S01, the control device G2 determines whether the lift cylinder A10 is currently in the most contracted state (predetermined length) based on the current signal of the lift contraction sensor S2. If the signal of the lift contraction sensor S2 is ON and the lift cylinder A10 is in the most contracted state (in this embodiment, the relative inclination angle of the loading/unloading arm A3 to the chassis 3 is 0), the control device G2 moves the procedure from step S01 to step S02. If the signal of the lift contraction sensor S2 is OFF and the lift cylinder A10 is in an extended state from the most contracted state (in this embodiment, the relative inclination angle of the loading/unloading arm A3 to the chassis 3 is greater than 0), the control device G2 moves the procedure from step S01 to step S04.

Step S02
When the procedure proceeds to step S02, the control device G2 judges whether the current time is the start time of extension of the lift cylinder A10 from the minimum contraction state based on the signal of the operating device H stored in memory. Specifically, based on the data stored in memory, it judges whether the current operation signal associated with the operation of the lowering button for loading and unloading work of the operating device H is ON and the operation signal one cycle time ago (e.g., 0.1 s ago) is OFF. If the current time is the start time of extension of the lift cylinder A10 from the minimum contraction state, the control device G2 proceeds from step S02 to step S03. If the current time is not the start time of extension of the lift cylinder A10 from the minimum contraction state, the control device G2 proceeds from step S01 to step S21.

Step S03
When the procedure proceeds to step S03, the control device G2 stores (registers) in memory the output value θt of the inclination sensor S1 stored in memory at the start of the current cycle as the chassis inclination angle θ1, ends the current cycle, and returns the procedure to the start.

Step S04
When the lift cylinder A10 starts extending from the maximum contraction, the judgment in step S01 is no longer satisfied, and the control device G2 moves the procedure from step S01 to step S04. In step S04, the control device G2 judges whether the current time is the time when the PTO was switched from on to off based on the signal of the PTO switch P stored in memory at the start of each of the current cycle and the previous cycle. Specifically, based on the stored data in the memory, it judges whether the current operation signal of the PTO switch P is off and the operation signal one cycle time ago was on. If the current time is the time when the PTO was switched off, the control device G2 moves the procedure from step S04 to step S18. If the current time is not the time when the PTO was switched off, the control device G2 moves the procedure from step S04 to step S05.

Step S05
When the procedure proceeds to step S05, the control device G2 determines whether the current time is the time when the PTO was switched from off to on, based on the signal of the PTO switch P stored in memory at the start of each of the current cycle and the previous cycle. Specifically, based on the data stored in memory, it determines whether the current operation signal of the PTO switch P is on and the operation signal one cycle time ago was off. If the current time is the time when the PTO was switched on, the control device G2 proceeds from step S05 to step S19. If the current time is not the time when the PTO was switched on, the control device G2 proceeds from step S05 to step S06.

Step S06
When the procedure proceeds to step S06, the control device G2 judges whether the current time is the time when the loading/unloading operation is switched from on to off (the start time of the operation interruption) based on the signal of the operating device H stored in memory at the start of each of the current cycle and the previous cycle. Specifically, based on the data stored in the memory, it judges whether the current operating signal related to the loading/unloading work is off and the operating signal one cycle time ago was on. If the current time is the time when the loading/unloading operation is switched from on to off, the control device G2 proceeds from step S06 to step S11. If the current time is not the time when the loading/unloading operation is switched from on to off, the control device G2 proceeds from step S06 to step S07.

Step S07
When the procedure proceeds to step S07, the control device G2 judges whether the current time is the time when the loading/unloading operation is switched from OFF to ON (operation restart time) based on the signal of the operating device H stored in memory at the start of each of the current cycle and the previous cycle. Specifically, based on the data stored in the memory, it judges whether the current operating signal related to the loading/unloading work is ON and the operating signal one cycle time ago was OFF. If the current time is the time when the loading/unloading operation is switched from OFF to ON, the control device G2 proceeds from step S07 to step S14. If the current time is not the time when the loading/unloading operation is switched from OFF to ON, the control device G2 proceeds from step S07 to step S08.

Step S08
When the procedure proceeds to step S08, the control device G2 determines whether the PTO is on and the loading/unloading operation is on based on the signals of the PTO switch P and the operation device H stored in memory at the start of the current cycle. If the PTO is on and the loading/unloading operation is on, the control device G2 proceeds from step S08 to step S09. If at least one of the PTO and the loading/unloading operation is off, the control device G2 proceeds from step S08 to step S12.

Step S09
When the procedure proceeds to step S09, the control device G2 refers to the memory and determines whether or not a calculation invalidation setting (described later) that invalidates the calculation of the relative inclination angle of the loading/unloading arm A3 is registered. If the calculation of the relative inclination angle of the loading/unloading arm A3 is invalid, the control device G2 ends the current cycle without calculating the arm rotation angle θarm and returns the procedure to the start. If the calculation of the relative inclination angle of the loading/unloading arm A3 is valid, the control device G2 proceeds from step S09 to step S10.

Step S10
When the procedure proceeds to step S10, the control device G2 calculates the arm rotation angle θarm from the difference between the output value θt of the tilt sensor S1 stored in memory at the start of the current cycle and the currently registered chassis tilt angle θ1. The control device G2 then stores the calculated arm rotation angle θarm in memory, ends the current cycle, and returns the procedure to the start.

Step S11
When the operation of the loading/unloading arm A3 is temporarily stopped during its operation, the loading/unloading operation by the operating device H is interrupted. In this case, the procedure is led to step S06, and the determination in step S06 is satisfied, and the procedure proceeds to step S11. When the procedure proceeds to step S11, the control device G2 starts timing the operation-off time t, ends the current cycle, and returns the procedure to the start. The operation-off time t is the duration of the state in which there is no loading/unloading operation.

Step S12
When the counting of the operation-off time t starts and the PTO is on and the loading/unloading operation is off, the procedure is led to step S12, where the control device G2 judges whether the current operation-off time t has reached a preset set time t0 (e.g., 2 s). If the current operation-off time t is the set time t0, the control device G2 moves the procedure from step S12 to step S13. If the current operation-off time t has not yet reached the set time t0 or has already exceeded the set time t0, the control device G2 ends the current cycle and returns the procedure to the start.

Step S13
When the procedure proceeds to step S13, the control device G2 stores (registers) in memory the output value θt of the inclination sensor S1 stored in memory at the start of the current cycle as the inclination angle θ2 when operation is off, and then ends the current cycle and returns the procedure to the start.

Step S14
When the counting of the operation-off time t is started and the PTO is turned on to resume loading/unloading operation, the procedure is led from step S07 to step S14, and the control device G2 judges whether the operation-off tilt angle θ2 is registered (or whether the operation-off time t exceeds the set time t0). If the operation-off tilt angle θ2 is registered, the control device G2 advances the procedure from step S14 to step S15, and if the operation-off tilt angle θ2 is not registered, the control device G2 advances the procedure from step S14 to step S17, bypassing steps S15 and S16.

Step S15
When the procedure proceeds to step S15, the control device G2 calculates the difference (absolute value) between the output value θt of the tilt sensor S1 stored in memory at the start of the current cycle and the tilt angle θ2 when the operation is off, and determines whether the difference exceeds a predetermined allowable value θa. If the tilt angle θ2 when the operation is off changes during the operation off and the difference exceeds the allowable value θa, the control device G2 proceeds from step S15 to step S16. If the difference is equal to or smaller than the allowable value θa, the control device G2 bypasses step S15 to step S16 and proceeds to step S17.

Step S16
When the procedure proceeds to step S16, the control device G2 stores (registers) in memory a calculation invalidation setting (flag or the like) that invalidates the calculation of the arm rotation angle θarm, and proceeds to step S17.

Step S17
When the procedure proceeds to step S17, the control device G2 resets the operation-off time t, ends the current cycle, and returns the procedure to the start.

Step S18
When the lift cylinder A10 is extended beyond the maximum contraction state, the loading/unloading operation is stopped and the PTO is turned off, and the procedure moves from step S04 to step S18. When the procedure moves to step S18, the control device G2 stores (registers) the output value θt of the inclination sensor S1 stored in the memory at the start of the current cycle as the PTO-off inclination angle θ3, ends the current cycle, and returns to the start of the procedure. After that, while the PTO is off, typically, steps S01, S04-S08, and S12 are looped. During this period, the PTO is off, so the loading/unloading operation is also off, but the operation-off time t is measured only when the PTO is on, so it is not measured while the PTO is off. Therefore, the procedure does not move from step S12 to step S13 and the operation-off inclination angle θ2 is not registered.

Step S19
Thereafter, when the PTO is turned on, the procedure is led from step S05 to step S19, where the control device G2 judges whether the PTO off tilt angle θ3 is registered. If the PTO off tilt angle θ3 is registered, the control device G2 proceeds from step S19 to step S20, and if the PTO off tilt angle θ3 is not registered, the control device G2 ends the current cycle and returns the procedure to the start.

Step S20
When the procedure proceeds to step S20, the control device G2 calculates the difference between the output value θt of the inclination sensor S1 stored in memory at the start of the current cycle and the PTO-off inclination angle θ3, and adds this difference as a correction value to the chassis inclination angle θ1. If the chassis inclination angle θ1 changes while the PTO is off, the amount of change corresponds to the difference between θt and θ3, so the chassis inclination angle θ1 is corrected by adding this difference. The control device G2 updates the chassis inclination angle θ1 registered in memory to the corrected value, ends the current cycle, and returns the procedure to the start.

Step S21
After that, the lift button of the operating device H is operated continuously, the lift cylinder A10 is contracted to the most contracted state, and the loading/unloading arm A3 is placed on the vehicle chassis 3. In step S21, the control device G2 judges whether the current moment is the moment when the lift cylinder A10 is contracted to the most contracted state based on the signal of the operating device H stored in the memory. Specifically, based on the data stored in the memory, it judges whether the current operation signal associated with the operation of the lift button for loading/unloading work of the operating device H is off and the operation signal one cycle time ago (for example, 0.1 s ago) is on. If the current moment is the moment when the lift cylinder A10 is contracted to the most contracted state, the control device G2 moves the procedure from step S21 to steps S22-S25. If the current moment is not the moment when the lift cylinder A10 is contracted to the most contracted state (i.e., if it has been in the most contracted state for one cycle or more before), the control device G2 bypasses steps S21 to S22-S25, ends the current cycle, and returns to the start of the procedure.

Steps S22 to S25
When the procedure proceeds to steps S22-S25, the control device G2 clears all registered chassis inclination angle θ1, operation-off inclination angle θ2, PTO-off inclination angle θ3, and invalid calculation settings, ends the current cycle, and returns the procedure to the start. The order of clearing the chassis inclination angle θ1 (step S22), the operation-off inclination angle θ2 (step S23), the PTO-off inclination angle θ3 (step S24), and the invalid calculation settings (step S25) may be random (or may be performed simultaneously).

As described above, when the control device G2 calculates the relative inclination angle of the loading/unloading arm A3 with respect to the chassis 3, it sets the chassis inclination angle θ1 as a reference for calculating the relative inclination angle for each operation opportunity of the loading/unloading arm A3, and stores (registers) it in memory (step S03). As the chassis inclination angle θ1, the output value θt of the inclination sensor S1 before the loading/unloading arm A3 starts to tilt at a predetermined angle (0° in the above embodiment) with respect to the chassis 3 is stored based on the signals of the inclination sensor S1 and the lift contraction sensor S2. In this embodiment, the output value θt at the start of tilting is stored as the output value θt before the start of tilting, but for example, the output value θt during the operation of the slide cylinder A12 before the loading/unloading arm A3 starts to tilt may be stored. The state in which the loading/unloading arm A3 is at a predetermined angle with respect to the chassis 3 can be determined by the output of the lift contraction sensor S2 being on (step S01). Whether the loading/unloading arm A3 has yet to start tilting can be determined based on the operation signal (output signal associated with operation of the lowering button or dump lift button) of the operating device H that operates the loading/unloading arm A3 (step S02). After storing the chassis inclination angle θ1 in this way, the control device G2 calculates the relative inclination angle of the loading/unloading arm A3 that changes with subsequent operations based on the output of the inclination sensor S1 after the loading/unloading arm A3 has started to tilt and the chassis inclination angle θ1 (i.e., from the difference between the two) (step S10).

However, if the difference (θ2-θt) between the outputs of the tilt sensor S1 when the operation of the operating device H is interrupted and when the operation is subsequently resumed exceeds the allowable value θa, the control device G2 invalidates the calculation of the relative tilt angle (steps S15, S16). In this embodiment, the time of interruption is not the time when the interruption of operation begins, but is assumed to be an interruption of operation that continues for a predetermined time (e.g., 2 s) or more, and the tilt angle θ2 when operation is off is set at the point in time when the predetermined time (2 s) has elapsed from the start of the interruption of operation (steps S12, S13).

In addition, if the PTO is turned off while the lift compression sensor S2 is off, the control device G2 corrects the chassis tilt angle θ1 using the difference (θt-θ3) between the outputs of the tilt sensor S1 at the time the PTO is turned off and the time it is first turned on thereafter as a correction value (step S20).

-effect-
(1) As described above, in this embodiment, when starting a loading/unloading operation or a dumping operation, the output value θt of the inclination sensor S1 before the loading/unloading arm A3 starts to tilt at a predetermined angle relative to the chassis 3 is stored as the chassis inclination angle θ1. In this way, by taking the difference between the output value θt (chassis inclination angle θ1) of the inclination sensor S1 at the start of the operation and the output value θt of the inclination sensor S1 after the loading/unloading arm A3 starts to tilt, the relative inclination angle of the loading/unloading arm A3 to the chassis 3 can be calculated even if the chassis 3 does not have an inclination sensor. If a value registered before the operation is used as the reference chassis inclination angle θ1, and the inclination angle of the chassis 3 differs between the time of registration and the time of the start of the operation, an error will occur in the calculation of the relative inclination angle of the loading/unloading arm A3. In this respect, in the case of this embodiment, the chassis inclination angle θ1 is measured at the start of the operation, so the relative inclination angle of the loading/unloading arm A3 can be calculated with high accuracy.

Thus, while limiting the number of inclination sensors, it is possible to grasp the chassis inclination angle θ1 and calculate the relative inclination angle and rotation angle of the loading/unloading arm A3 with respect to the chassis 3. Because the number of inclination sensors S1 is reduced, the manufacturing costs of the loading vehicle are reduced and the complexity of the wiring layout is also reduced.

(2) A limit switch that detects a predetermined length of the lift cylinder A10 can be used as the lift compression sensor S2 required to determine the conditions for the timing of setting the chassis tilt angle θ1. This limit switch is generally provided in many cargo handling vehicles, and the fact that existing equipment can be effectively utilized contributes to reducing manufacturing costs and simplifying the configuration.

(3) Some users may move the loading vehicle by suspending operation of the loading/unloading arm A3 with the PTO on, for example, to adjust the position of the vehicle when loading or unloading a container. In this case, the deviation in the output value of the inclination sensor S1 (i.e., the change in the inclination angle of the chassis 3) before and after the operation is suspended may exceed the allowable value θa. Even if the operation of the loading/unloading arm A3 is started and then suspended to use the jack D, the output value of the inclination sensor S1 may deviate beyond the allowable value θa before and after the operation is suspended. In these cases, the accuracy of the relative inclination angle of the loading/unloading arm A3 after operation is resumed decreases.

Therefore, in this embodiment, if the difference between the output value of the inclination sensor S1 when the operation of the lift cylinder A10 by the operating device H is interrupted (inclination angle θ2 when operation is off) and the output value θt of the inclination sensor S1 when operation is resumed exceeds the allowable value θa, the calculation of the relative inclination angle of the loading/unloading arm A3 is invalidated. In other words, even if a deviation occurs in the output value of the inclination sensor S1 before and after the operation is interrupted, as long as the deviation is within the allowable value θa, the relative inclination angle can be continuously calculated even after operation is resumed.

(4) When the operation of the loading/unloading arm A3 is stopped, braking of the loading/unloading arm A3 may be delayed slightly due to inertia, or it may take some time for the loading/unloading arm A3 to come to a stop due to the influence of bending of the loading/unloading arm A3 or the chassis 3.

Therefore, in this embodiment, when registering the tilt angle θ2 when operation is off, the output value θt of the tilt sensor S1 at the point when the operation is interrupted for a set time t0 (e.g., 2 s) is registered, rather than when the operation is interrupted (the point when the operation is stopped). By waiting for the set time t0 after the operation is stopped and measuring the tilt angle θ2 when operation is off, the output value of the tilt sensor S1 after it has come to a proper standstill can be registered, and the deviation of the tilt sensor S1 before and after the operation is interrupted can be detected with high accuracy.

In addition, in order to fine-tune the position of the hook F when loading a container, the operating device H may be operated in small increments, a process known as inching. In this case, by ensuring a hold time of the set time t0, it is possible to avoid registering the output value of the tilt sensor S1 each time the button of the operating device H is turned on and off, which is repeated at short intervals during inching, and to reduce the processing burden on the control device G2. When the loading/unloading arm A3 is moved in small increments, as in inching, there is little possibility that the output value of the tilt sensor S1 will deviate before and after a very short interruption in operation, and this has the great advantage of reducing the processing burden on the control device G2.

(5) There are cases where the loading/unloading vehicle is moved by running it during the operation of the loading/unloading arm A3. In this case, if the ground gradient is different before and after the movement, the chassis inclination angle θ1 registered at the start of the work deviates from the actual value after the movement, and if the chassis inclination angle θ1 is used as is, the relative inclination angle of the loading/unloading arm A3 after the movement cannot be accurately determined.

Therefore, in this embodiment, the output value θt of the inclination sensor S1 when the PTO is turned off is registered as the PTO-off inclination angle θ3, and the difference in the output value θt of the inclination sensor S1 when the PTO is turned on for the first time thereafter is used as a correction value to correct the registered chassis inclination angle θ1. Since the PTO is usually turned off to move the loading vehicle, correcting the chassis inclination angle θ1 in this manner makes it possible to accurately calculate the relative inclination angle of the loading/unloading arm A3 even after the movement.

(6) In this embodiment, the target is a loading/unloading vehicle capable of both container loading and dumping operations, and the relative inclination angle (dump angle θtilt, arm swing angle θarm) of the loading/unloading arm A3 for both operations can be calculated separately based on the signal from the operating device H. Since the dump angle θtilt and the arm swing angle θarm can be calculated separately, information regarding container loading and unloading operations and dumping operations can be appropriately grasped and managed.

--Modifications--
In the above, the present invention has been described by way of example with respect to a loading vehicle having a container loading/unloading function and a dumping function, but the present invention can be applied to any loading vehicle in which the arm is inclined relative to the chassis, and either the loading/unloading function or the dumping function can be omitted. In other words, the present invention can also be applied to a loading vehicle having only a dumping function and no loading/unloading function for cargo boxes, such as a dump truck, or a container loading vehicle having only a container loading/unloading function and no dumping function, and the same effect can be obtained. In the case of a dump truck, the inclination sensor S1 can be installed on the cargo box or the girder on its bottom surface, in addition to the arm that supports the cargo box (vessel).

In addition, an example has been described in which the output value θt of the inclination sensor S1 when the loading/unloading arm A3 is at 0° relative to the chassis 3 is registered as the chassis inclination angle θ1, but depending on the loading vehicle, for example, the lift cylinder A10 may be in a fully contracted state and the loading/unloading arm may be inclined relative to the chassis. In such a case, the output value θt of the inclination sensor S1 when the loading/unloading arm A3 is inclined at a specified angle (for example, 10° or 20°) relative to the chassis 3 may be registered as the chassis inclination angle θ1.

In addition, while the above example shows a loading vehicle capable of loading both standard container X and special containers onto the chassis 3, the present invention can be applied to loading vehicles dedicated to standard containers and loading vehicles dedicated to special containers. The same effects can be obtained with the present invention when applied to either type of loading vehicle. Figures 14 to 20 show a loading vehicle dedicated to special containers as a modified example of the loading device of the present invention.

Figure 14 is a side view, Figure 15 is a plan view, and Figure 16 is a rear view of a cargo handling vehicle according to one modified example. Figures 14-16 correspond to Figures 1-3. Elements in this modified example that are similar to or correspond to those in the above embodiment are given the same reference numerals in Figures 14-16 as in the previously mentioned drawings, and their explanation will be omitted. As shown in Figures 14-16, the cargo handling vehicle according to the modified example differs from the cargo handling vehicle according to the above embodiment in that it does not have a container guide device B, adapter E, or support post A11. In addition, the dedicated container Y has a roller Y1 at the lower rear end and a locking member Y2 on which a hook F is attached at the front.

Figure 17 shows the dumping operation performed by the cargo handling vehicle of Figure 14, and Figures 18-20 show the loading operation of a special container performed by the cargo handling vehicle of Figure 14. Figures 18-20 correspond to Figures 11-12.

When performing dumping operations with the loading and unloading equipment shown in Figures 14-16, for example, when the dump lift operation is performed using the operating device H, the dump lock device described above is locked, and the lift cylinder A10 extends as shown in Figure 17, causing the dump frame A2 to stand up rearward together with the loading and unloading arms A3. This allows the contents of the container to be dumped. After that, when the dump lowering button for dumping operations is operated using the operating device H, the lift cylinder A10 contracts, causing the dump frame A2 to collapse together with the loading and unloading arms A3.

When loading the special container Y onto the vehicle frame 3, the loading vehicle is stopped at a predetermined position in front of the special container Y, the jack D is lowered, and the operation device H is used to perform a lowering operation to rotate the loading/unloading arm A3 backward, and the hook F is applied to the special container Y as shown in FIG. 18. After the hook F is applied to the special container Y, the operation device H is used to perform a lifting operation to rotate the loading/unloading arm A3 forward, and the special container Y is lifted onto the vehicle frame 3. As the loading/unloading arm A3 moves, the front side of the special container Y is lifted with the roller Y1 as a fulcrum, and the roller Y1 travels a predetermined distance on the ground and is received by the guide roller A5 as shown in FIG. 19. After that, the loading/unloading arm A3 further rotates forward, and the special container Y is guided by the container guide device B and lifted to the top of the vehicle frame 3 as shown in FIG. 20. When the loading/unloading arm A3 is horizontally lowered, the hook arm A8 is advanced to fix the special container Y, and the loading operation of the special container Y is completed. The unloading process of lowering the special container Y from the vehicle frame 3 can be carried out by reversing the above steps.

Even when targeting loading and unloading equipment dedicated to such special containers, the present invention can be applied in the same manner as the above embodiment, and similar effects can be obtained.

3... chassis, A3... loading/unloading arm (arm), A10... lift cylinder, G2... control device, S1... tilt sensor, S2... lift retraction sensor (detector), θ1... chassis tilt angle, θ2... tilt angle when operation is off (tilt sensor output when operation is interrupted), θ3... tilt angle when PTO is off (tilt sensor output when PTO is turned off), θarm... arm rotation angle (relative tilt angle of arm to chassis), θt... tilt sensor output, θtilt... dump angle (relative tilt angle of arm to chassis)

Claims (6)

The chassis and
an arm for supporting a shipping box against the vehicle chassis;
an inclination sensor that detects an angle of the arm based on the direction of gravity;
a detector for detecting a state in which the arm is at a predetermined angle with respect to the chassis;
A control device that calculates a relative inclination angle of the arm with respect to the chassis,
The control device includes:
based on outputs of the tilt sensor and the detector, an output of the tilt sensor before the arm starts to tilt at the predetermined angle with respect to the chassis is stored as a chassis tilt angle;
a tilt sensor for detecting a tilt angle of the vehicle chassis after the arm starts tilting and detecting an output of the tilt sensor from the tilt sensor and a tilt angle of the vehicle chassis after the arm starts tilting; In the loading vehicle of claim 1,
The loading vehicle is characterized in that the detector detects a state in which the arm is at 0 degrees with respect to the chassis. In the loading vehicle according to claim 1 or 2,
The loading vehicle is characterized in that the control device determines before the arm starts to tilt based on an output of an operating device that operates the arm. In the loading vehicle of claim 3,
The control device of the loading vehicle is characterized in that, if a difference between the outputs of the inclination sensors when operation of the operating device is interrupted and when operation is resumed exceeds an allowable value, the control device invalidates the calculation of the relative inclination angle. The loading vehicle according to claim 4,
The cargo handling vehicle is characterized in that the operation interruption occurs when the set time has elapsed from the start of an operation interruption that continues for a set time or more. In any one of claims 1 to 5,
The control device corrects the chassis inclination angle by using the difference in output from the inclination sensor between the time when the PTO is turned off and the time when it is turned on for the first time thereafter as a correction value.

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