Cargo box overturning device, cargo box overturning control method and articulated dump truck

Abstract

The invention belongs to the technical field of articulated dump trucks and discloses a cargo box flipping device, a cargo box flipping control method and an articulated dump truck. The output end of a pressure oil source is connected to an oil supply pipeline; the oil tank is connected to an oil return pipeline; a lifting oil cylinder has a piston rod for driving the cargo box to move, and the piston rod divides the inner cavity of the lifting oil cylinder into a rodless cavity and a rod cavity; a multi-way valve can move along a set direction and has an ascending position and a descending position, and a reversing valve is provided at the ascending position. When the multi-way valve is in the ascending position, the oil supply pipeline is connected to the rodless cavity, and the oil supply pipeline is connected to a first control end of the reversing valve. The reversing valve is used to connect or disconnect the return oil pipeline with the rod cavity. When the return oil pipeline is connected to the rod cavity, the piston rod of the lifting oil cylinder can be extended. When the return oil pipeline is disconnected from the rod cavity, the cargo box can be prevented from continuing to flip, thereby avoiding the cylinder pulling phenomenon. When the multi-way valve is in the descending position, the lifting oil cylinder can drive the cargo box to descend relative to the vehicle frame.

Description

Technical Field

[0001] The present invention relates to the technical field of articulated dump trucks, and in particular to a cargo box overturning device, a cargo box overturning control method and an articulated dump truck. Background Art

[0002] In an articulated dump truck, the cargo box is usually hinged to the rear end of the frame, and the oil is controlled by a pressure oil source and a reversing valve to enter and exit the rodless chamber or rod chamber of the lifting cylinder, so that the movement of the lifting cylinder drives the cargo box to flip relative to the frame. In order to increase the unloading speed of the articulated dump truck, the cargo box needs to flip at a larger angle relative to the frame. At this time, if the angle of the cargo box flipping is too large, along the front and rear direction of the frame, it may cause the center of gravity of the cargo box to pass the hinge point between the cargo box and the frame. At this time, the cargo box will quickly flip downward and backward, causing the piston rod and cylinder head of the lifting cylinder to detach from the lifting cylinder, resulting in cylinder pulling. Summary of the invention

[0003] According to one aspect of the present invention, the present invention provides a cargo box flipping device to solve the problem in the prior art that if the cargo box is flipped at too large an angle, a cylinder pulling phenomenon may occur.

[0004] To achieve the above object, the present invention adopts the following technical solutions:

[0005] A cargo box flipping device is arranged on the vehicle frame and is used to drive the cargo box to flip relative to the vehicle frame;

[0006] The cargo box turning device comprises:

[0007] A pressure oil source, the output end of which is connected to an oil supply pipeline;

[0008] Fuel tank, connected to the oil return line;

[0009] A lifting cylinder having a piston rod for driving the cargo box to move, wherein the piston rod divides the inner cavity of the lifting cylinder into a rodless cavity and a rod cavity;

[0010] A multi-way valve can move in a set direction and has an ascending position and a descending position. A reversing valve is provided at the ascending position. When the multi-way valve is in the ascending position, the oil supply line is connected to the rodless chamber, and the oil supply line is connected to the first control end of the reversing valve. The reversing valve is used to connect or disconnect the return oil line with the rod chamber; when the multi-way valve is in the descending position, the oil supply line is connected to the rod chamber, and the return oil line is connected to the rodless chamber.

[0011] As a preferred solution of the cargo box flipping device, the reversing valve has a connected position and a non-connected position. When the reversing valve is in the connected position, the return oil pipeline is connected to the rod chamber, and when the reversing valve is in the non-connected position, the return oil pipeline is disconnected from the rod chamber. The oil in the oil supply pipeline is used to drive the reversing valve to move toward the connected position, and the second control end of the reversing valve is connected to an elastic member, which is used to provide an elastic force to make the reversing valve move toward the non-connected position.

[0012] As a preferred solution of the cargo box flipping device, the multi-way valve can also move in a set direction and have a stop position. When the multi-way valve is in the stop position, the oil supply line is disconnected from the rodless chamber and the rod chamber, and the oil return line is disconnected from the rodless chamber and the rod chamber.

[0013] As a preferred solution for the cargo box flipping device, the multi-way valve can also move in a set direction and have a floating position. When the multi-way valve is in the floating position, the oil supply line is connected to the rod chamber through a connecting line, and the oil return line is connected to the rodless chamber through a floating line, and the cross-sectional area of ​​the floating line is smaller than the cross-sectional area of ​​the connecting line.

[0014] As a preferred solution of the cargo box turning device, it also includes a pilot oil source and a pilot valve connected to the pilot oil source, the pilot valve is used to connect or disconnect the control end of the multi-way valve with the pilot oil source, when the control end of the multi-way valve is connected to the pilot oil source, the pilot oil source is used to drive the multi-way valve to move in a set direction.

[0015] According to another aspect of the present invention, a cargo box flipping control method is provided, which is implemented by the above-mentioned cargo box flipping device, and the cargo box flipping control method includes a cargo box rising control method, and the cargo box rising control method includes:

[0016] S100: Acquire a longitudinal tilt angle of the frame along the front-rear direction of the vehicle body and a lateral tilt angle along the left-right direction of the vehicle body;

[0017] S110: comparing the longitudinal inclination angle with a first set angle, and comparing the lateral inclination angle with a second set angle;

[0018] If the longitudinal tilt angle is not less than the first set angle, or the lateral tilt angle is not less than the second set angle, executing step S120;

[0019] S120: Preventing the multi-way valve from moving toward the rising position.

[0020] As a preferred solution of the cargo box overturning control method, in step S110, if the longitudinal tilt angle is less than the first set angle, or the lateral tilt angle is less than the second set angle, step S130 is executed;

[0021] S130: confirming that the multi-way valve is in the ascending position;

[0022] S140: Obtaining a critical angle of the cargo box according to the longitudinal tilt angle and the lateral tilt angle;

[0023] S150: Obtaining a flip angle of the cargo box relative to the vehicle frame;

[0024] S160: Compare the flip angle with the critical angle of the cargo box;

[0025] If the flipping angle is not less than the critical angle of the cargo box, executing step S170;

[0026] S170: Issue a warning message.

[0027] As a preferred solution of the cargo box flipping control method, in step S160, if the flipping angle is less than the cargo box critical angle, return to step S150.

[0028] As a preferred solution of the cargo box overturning control method, the multi-way valve can also move in a set direction and have a floating position. When the multi-way valve is in the floating position, the oil supply pipeline is connected to the rod chamber through a connecting pipeline, and the oil return pipeline is connected to the rodless chamber through a floating pipeline, and the cross-sectional area of ​​the floating pipeline is smaller than the cross-sectional area of ​​the connecting pipeline;

[0029] The cargo box overturning control method also includes a cargo box lowering control method, and the cargo box lowering control method includes:

[0030] S200: confirming that the multi-way valve is in a descending position;

[0031] S210: Obtaining a flip angle of the cargo box relative to the vehicle frame;

[0032] S220: Compare the flip angle with the floating critical angle;

[0033] If the flip angle is not greater than the floating critical angle, executing step S230;

[0034] S230: Control the multi-way valve to move to a floating position.

[0035] According to another aspect of the present invention, an articulated dump truck is provided, comprising the above-mentioned cargo box turning device, and also comprising a frame and a cargo box hinged to the frame, wherein the cargo box turning device is arranged on the frame and is used to drive the cargo box to turn relative to the frame.

[0036] The beneficial effects of the present invention are:

[0037] The present invention provides a cargo box flipping device, which is arranged on a vehicle frame and is used to drive the cargo box to flip relative to the vehicle frame. The cargo box flipping device includes a pressure oil source, an oil tank, a lifting cylinder and a multi-way valve. The output end of the pressure oil source is connected to an oil supply pipeline; the oil tank is connected to an oil return pipeline; the lifting cylinder has a piston rod for driving the movement of the cargo box, and the piston rod divides the inner cavity of the lifting cylinder into a rodless cavity and a rod cavity; the multi-way valve can move in a set direction and has an ascending position and a descending position, and a reversing valve is arranged at the ascending position. When the multi-way valve is in the ascending position, the oil supply pipeline is connected to the rodless cavity, and the oil supply pipeline is connected to the first control end of the reversing valve, and the reversing valve is used to make the oil return pipeline Connected or disconnected with the rod chamber, when the return oil line is connected to the rod chamber, the oil supply line can inject oil into the rodless chamber, and the oil in the rod chamber can flow into the oil tank through the return oil line, so that the piston rod of the lifting cylinder extends to drive the cargo box to rise relative to the frame; when the return oil line is disconnected from the rod chamber, the oil in the rod chamber cannot flow into the oil tank through the return oil line. At this time, if the flip angle of the cargo box is too large, the cargo box will not continue to flip because there is still a part of oil in the rod chamber, so that the angle of the cargo box relative to the frame remains unchanged. When the multi-way valve is in the descending position, the oil supply line is connected to the rod chamber, and the return oil line is connected to the rodless chamber, so that the oil supply line can inject oil into the rod chamber, and the oil in the rodless chamber can flow into the oil tank through the return oil line, so that the piston rod of the lifting cylinder retracts to drive the cargo box to descend relative to the frame. In the cargo box flipping device, when the cargo box flips over at an excessively large angle relative to the vehicle frame, the reversing valve can be used to cut off the connection between the oil return pipeline and the rod chamber, thereby preventing the cargo box from continuing to flip and avoiding the cylinder pulling phenomenon.

[0038] The present invention also provides a cargo box flipping control method, which is implemented through the above-mentioned cargo box flipping device. The cargo box flipping control method includes a cargo box rising control method. In the cargo box rising control method, the longitudinal inclination angle of the frame along the front and rear direction of the vehicle body and the lateral inclination angle along the left and right direction of the vehicle body are obtained; the longitudinal inclination angle is compared with the first set angle, and the lateral inclination angle is compared with the second set angle; if the longitudinal inclination angle is not less than the first set angle, or the lateral inclination angle is not less than the second set angle, it indicates that the frame is seriously tilted in the lateral or longitudinal direction at this time. At this time, if the cargo box is flipped, it is very likely to cause the articulated dump truck to roll over or the cargo box to tip backwards, thereby preventing the multi-way valve from moving toward the rising position, thereby preventing the cargo box from flipping relative to the frame.

[0039] The present invention also provides an articulated dump truck, comprising the above-mentioned cargo box flipping device, and also comprising a vehicle frame and a cargo box hinged to the vehicle frame, wherein the cargo box flipping device is arranged on the vehicle frame and is used to drive the cargo box to flip relative to the vehicle frame. In the cargo box flipping device, when the angle at which the cargo box flips relative to the vehicle frame is too large, the connection between the return oil pipeline and the rod chamber can be cut off by a reversing valve, thereby preventing the cargo box from continuing to flip and avoiding the phenomenon of cylinder pulling. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] Figure 1 2 is a schematic diagram of the structure of a cargo box turning device according to an embodiment of the present invention;

[0041] Figure 2 is a schematic structural diagram of a vehicle frame and a cargo box in an embodiment of the present invention;

[0042] Figure 3 is a structural schematic diagram of a reversing valve in an embodiment of the present invention;

[0043] Figure 4 is a flow chart of a method for controlling the rise of a cargo box in an embodiment of the present invention;

[0044] Figure 5 It is a flow chart of the cargo box descent control method in an embodiment of the present invention.

[0045] In the figure:

[0046] 100, frame; 200, cargo box;

[0047] 1. Pressure oil source; 11. Oil supply pipeline;

[0048] 2. Oil tank; 21. Oil return line;

[0049] 3. Lifting cylinder; 31. Rodless chamber; 32. Rod chamber;

[0050] 4. Multi-way valve; 41. Return spring; 401. Pressure oil port; 402. First port; 403. Second port;

[0051] 5. reversing valve; 51. elastic member; 501. first chamber; 502. second chamber;

[0052] 6. Pilot oil source;

[0053] 7. Pilot valve;

[0054] 81. Dual-axis angle sensor; 82. Cargo box angle sensor; 83. Display instrument. DETAILED DESCRIPTION

[0055] The present invention will be further described in detail below in conjunction with the accompanying drawings and embodiments. It is to be understood that the specific embodiments described herein are only used to explain the present invention, rather than to limit the present invention. It should also be noted that, for ease of description, only parts related to the present invention, rather than all structures, are shown in the accompanying drawings.

[0056] In the description of the present invention, unless otherwise clearly specified and limited, the terms "connected", "connected", and "fixed" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0057] In the present invention, unless otherwise clearly specified and limited, a first feature being "above" or "below" a second feature may include that the first and second features are in direct contact, or may include that the first and second features are not in direct contact but are in contact through another feature between them. Moreover, a first feature being "above", "above" and "above" a second feature includes that the first feature is directly above and obliquely above the second feature, or simply indicates that the first feature is higher in level than the second feature. A first feature being "below", "below" and "below" a second feature includes that the first feature is directly below and obliquely below the second feature, or simply indicates that the first feature is lower in level than the second feature.

[0058] In the description of this embodiment, the terms "upper", "lower", "left", "right" and other directions or positional relationships are based on the directions or positional relationships shown in the drawings, and are only for the convenience of description and simplification of operation, rather than indicating or implying that the device or element referred to must have a specific direction, be constructed and operate in a specific direction, and therefore cannot be understood as limiting the present invention. In addition, the terms "first" and "second" are only used to distinguish in the description and have no special meaning.

[0059] Embodiment 1

[0060] In an articulated dump truck, the cargo box is usually hinged to the rear end of the frame, and the oil is controlled by a pressure oil source and a reversing valve to enter and exit the rodless chamber or rod chamber of the lifting cylinder, so that the movement of the lifting cylinder drives the cargo box to flip relative to the frame. In order to increase the unloading speed of the articulated dump truck, the cargo box needs to flip at a larger angle relative to the frame. At this time, if the angle of the cargo box flipping is too large, along the front and rear direction of the frame, it may cause the center of gravity of the cargo box to pass the hinge point between the cargo box and the frame. At this time, the cargo box will quickly flip downward and backward, causing the piston rod and cylinder head of the lifting cylinder to detach from the lifting cylinder, resulting in cylinder pulling.

[0061] In view of the above problems, this embodiment provides a cargo box flipping device to solve the problem in the prior art that if the cargo box is flipped at a too large angle, a cylinder pull phenomenon may occur, and can be used in the technical field of articulated dump trucks.

[0062] Reference Figure 1-Figure 2 The cargo box flipping device is arranged on the vehicle frame and is used to drive the cargo box 200 to flip relative to the vehicle frame 100. The cargo box flipping device includes a pressure oil source 1, a fuel tank 2, a lifting cylinder 3 and a multi-way valve 4. The output end of the pressure oil source 1 is connected to the oil supply pipeline 11. In this embodiment, the pressure oil source 1 is an oil supply pump, the input end of the oil supply pump is connected to the fuel tank 2, and the fuel tank 2 is connected to the oil return pipeline 21. The lifting cylinder 3 has a piston rod for driving the cargo box 200 to move, and the piston rod divides the inner cavity of the lifting cylinder 3 into a rodless cavity 31 and a rod cavity 32; the multi-way valve 4 can move along the set direction and has an ascending position and a descending position, and a reversing valve 5 is provided at the ascending position. When the multi-way valve 4 is in the ascending position, the oil supply pipeline 11 is connected to the rodless cavity 31, and the oil supply pipeline 11 is connected to the first control end of the reversing valve 5. The reversing valve 5 is used to connect or disconnect the return oil pipeline 21 with the rod cavity 32. When the return oil pipeline 21 is connected to the rod cavity 32, the supply oil pipeline 1 1 can inject oil into the rodless chamber 31, and the oil in the rod chamber 32 can flow into the oil tank 2 through the oil return pipeline 21, so that the piston rod of the lifting cylinder 3 extends to drive the cargo box 200 to rise relative to the frame 100; when the oil return pipeline 21 is disconnected from the rod chamber 32, the oil in the rod chamber 32 cannot flow into the oil tank 2 through the oil return pipeline 21. At this time, if the turning angle of the cargo box 200 is too large, since there is still a part of oil in the rod chamber 32, the cargo box 200 will not continue to turn over, and the angle of the cargo box 200 relative to the frame 100 can be kept unchanged. When the multi-way valve 4 is in the descending position, the oil supply line 11 is connected to the rod chamber 32, and the oil return line 21 is connected to the rodless chamber 31, so that the oil supply line 11 can inject oil into the rod chamber 32, and the oil in the rodless chamber 31 can flow into the oil tank 2 through the oil return line 21, so that the piston rod of the lifting cylinder 3 is retracted to drive the cargo box 200 to descend relative to the frame 100. In the cargo box flipping device, when the angle of the cargo box 200 flipping relative to the frame 100 is too large, the connection between the oil return line 21 and the rod chamber 32 can be cut off by the reversing valve 5, so as to prevent the cargo box 200 from continuing to flip and avoid the cylinder pulling phenomenon.

[0063] Continue to refer to Figure 1-Figure 2The reversing valve 5 has a connection position and a non-connection position. When the reversing valve 5 is in the connection position, the return oil pipeline 21 is connected to the rod chamber 32. When the reversing valve 5 is in the non-connection position, the return oil pipeline 21 is disconnected from the rod chamber 32. The oil in the oil supply pipeline 11 is used to drive the reversing valve 5 to move toward the connection position. The second control end of the reversing valve 5 is connected to an elastic member 51. The elastic member 51 is used to provide an elastic force to move the reversing valve 5 toward the non-connection position, so that the reversing valve can be controlled by the oil pressure in the oil supply pipeline 11 and the elastic force of the elastic member 51. 5, specifically based on the comparison between the oil pressure of the oil supply line 11 and the force of the elastic member 51, the return oil line 21 is connected or disconnected with the rod chamber 32. When the multi-way valve 4 just moves to the rising position, the oil pressure in the oil supply line 11 is relatively large. Under the push of the oil, the reversing valve 5 moves toward the connecting position. At this time, the oil supply line 11 can inject oil into the rodless chamber 31, and the oil in the rod chamber 32 can flow into the oil tank 2 through the return oil line 21, thereby extending the piston rod of the lifting cylinder 3 to drive the cargo box 200 to rise relative to the frame 100. As the cargo box 200 continues to flip, along the front-to-back direction of the vehicle body, when the center of gravity of the cargo box 200 coincides with the hinge point between the cargo box 200 and the frame 100, the oil pressure in the oil supply line 11 reaches the maximum. At this time, if the cargo box 200 continues to flip, the oil pressure in the oil supply line 11 will drop rapidly. When the oil pressure in the oil supply line 11 is less than the elastic force of the elastic member 51, the elastic member 51 drives the reversing valve 5 to move toward the non-connected position. At this time, the reversing valve 5 cuts off the connection between the return oil line 21 and the rod chamber 32, thereby preventing the cargo box 200 from continuing to flip and avoiding the cylinder pulling phenomenon. By connecting the oil supply line 11 to the reversing valve 5 and providing the elastic member 51, the cargo box 200 can be automatically prevented from flipping after the center of gravity of the cargo box 200 passes the hinge point.

[0064] Optionally, the reversing valve 5 is arranged inside the multi-way valve 4 to save space and facilitate the arrangement of the hydraulic pipeline. Figure 3 As shown, the reversing valve 5 is arranged inside the multi-way valve 4, and forms a first cavity 501 and a second cavity 502. The multi-way valve 4 has a pressure oil port 401 communicating with the inner cavity of the oil supply pipeline 11, a first port 402 communicating with the inner cavity of the oil return pipeline 21, and a second port 403 communicating with the rod cavity 32. The oil in the oil supply pipeline 11 can enter the first cavity 501 through the pressure oil port 401. The first cavity 501 is spiral. The oil entering the first cavity 501 can push the reversing valve 5 to move toward the direction of the compression elastic member 51, so that the second cavity 502 is simultaneously communicated with the first port 402 and the second port 403, so that the oil return pipeline 21 is connected to the rod cavity 32.

[0065] Continue to refer to Figure 1-Figure 2The multi-way valve 4 can also move in a set direction and have a stop position. When the multi-way valve 4 is in the stop position, the oil supply line 11 is disconnected from the rodless chamber 31 and the rod chamber 32, and the oil return line 21 is disconnected from the rodless chamber 31 and the rod chamber 32, so that the flip angle of the cargo box 200 relative to the frame 100 remains unchanged, and can be switched to the stop position at any time during the process of the cargo box 200 rising or falling to maintain the current flip angle of the cargo box 200. Optionally, two return springs 41 are also connected to both ends of the multi-way valve 4, and the two return springs 41 are used to provide elastic force to move the multi-way valve 4 toward the stop position, so that the multi-way valve 4 is always in the stop position without being controlled by external forces.

[0066] Continue to refer to Figure 1-Figure 2 The multi-way valve 4 can also move in a set direction and have a floating position. When the multi-way valve 4 is in the floating position, the oil supply line 11 is connected to the rod chamber 32 through the connecting line, and the oil return line 21 is connected to the rodless chamber 31 through the floating line. The cross-sectional area of ​​the floating line is smaller than the cross-sectional area of ​​the connecting line, so that the oil flow rate in the floating line is smaller than the oil flow rate in the connecting line. The speed at which the oil in the rodless chamber 31 flows to the oil return line 21 is slower than the speed at which the oil in the oil supply line 11 flows to the rod chamber 32, so that the oil in the rodless chamber 31 flows out slowly, which can reduce the retraction speed of the lifting cylinder 3, and thus reduce the descending speed of the cargo box 200. When the cargo box 200 descends to the point of being in contact with the frame 100, the multi-way valve can be controlled to move to the floating position to prevent a collision between the cargo box 200 and the frame 100, thereby causing damage to the frame 100 or the cargo box 200.

[0067] Continue to refer to Figure 1-Figure 2 The cargo box overturning device also includes a pilot oil source 6 and a pilot valve 7 connected to the pilot oil source 6. The pilot valve 7 is used to connect or disconnect the control end of the multi-way valve 4 with the pilot oil source 6. When the control end of the multi-way valve 4 is connected to the pilot oil source 6, the pilot oil source 6 is used to drive the multi-way valve 4 to move along the set direction. In this embodiment, the multi-way valve 4 can move along the first direction and pass through the rising position, the stop position, the falling position and the floating position in sequence. The oil in the pipeline on the first side of the multi-way valve 4 is used to drive the multi-way valve 4 to move toward the floating position along the first direction, and the oil in the pipeline on the second side of the multi-way valve 4 is used to drive the multi-way valve 4 to move toward the rising position in the opposite direction of the first direction. Correspondingly, two pilot valves 7 are provided, one of which is used to control the connection or disconnection between the pipeline on the first side of the multi-way valve 4 and the pilot oil source 6, and the other pilot valve 7 is used to control the connection or disconnection between the pipeline on the second side of the multi-way valve 4 and the pilot oil source 6.

[0068] Embodiment 2

[0069] This embodiment provides a cargo box flipping control method, which is implemented by the cargo box flipping device in the above-mentioned embodiment 1. The cargo box flipping control method includes a cargo box rising control method, and the cargo box rising control method includes the following steps.

[0070] S100: Obtaining the longitudinal tilt angle of the frame 100 along the front-rear direction of the vehicle body and the lateral tilt angle along the left-right direction of the vehicle body.

[0071] Specifically, the angle can be obtained by a dual-axis angle sensor 81 provided on the vehicle frame 100 , which can simultaneously detect the longitudinal tilt angle of the vehicle frame 100 along the front-rear direction of the vehicle body and the lateral tilt angle along the left-right direction of the vehicle body.

[0072] S110: comparing the longitudinal tilt angle with the first set angle, and comparing the transverse tilt angle with the second set angle.

[0073] If the longitudinal tilt angle is not less than the first set angle, or the lateral tilt angle is not less than the second set angle, it indicates that the frame 100 is severely tilted in the lateral or longitudinal direction. At this time, if the cargo box 200 is flipped, it is very likely to cause the articulated dump truck to overturn or the cargo box to tip backwards, so step S120 is executed.

[0074] The first setting angle and the second setting angle can be obtained through a large number of experiments or simulation calculations in the early stage.

[0075] S120: Prevent the multi-way valve 4 from moving toward the rising position.

[0076] By preventing the multi-way valve 4 from moving toward the rising position, the cargo box 200 can be prevented from turning over relative to the vehicle frame 100. This can be achieved by controlling the pilot oil source 6 to stop supplying oil, so that the multi-way valve 4 can always be located at the stopping position under the action of the return spring 41. In addition, it can also be achieved by controlling the pilot valve 7 located on the second side of the multi-way valve 4. The pilot valve 7 located on the second side of the multi-way valve 4 keeps the pipeline located on the second side of the multi-way valve 4 and the pilot oil source 6 disconnected at all times, thereby preventing the oil from driving the multi-way valve 4 to move toward the rising position in the opposite direction of the first direction.

[0077] Optionally, in step S110, if the longitudinal tilt angle is less than the first set angle, and the lateral tilt angle is less than the second set angle, it indicates that the frame 100 is slightly tilted in the lateral and longitudinal directions at this time, and the cargo box 200 can be controlled to rise for unloading, thereby executing step S130.

[0078] S130: Confirm that the multi-way valve 4 is in the raised position.

[0079] Specifically, the position of the multi-way valve 4 can be obtained through devices such as position sensors.

[0080] S140: Obtaining a critical angle of the cargo box according to the longitudinal tilt angle and the lateral tilt angle.

[0081] It is understandable that different longitudinal tilt angles or lateral tilt angles of the frame 100 will result in different critical angles when the cargo box 200 is about to flip over, so it is necessary to obtain the cargo box critical angle based on the current longitudinal tilt angle and lateral tilt angle of the frame 100 at this time.

[0082] Specifically, the critical angle of the cargo box can be obtained based on the map of the longitudinal tilt angle, the lateral tilt angle and the critical angle of the cargo box. The map of the longitudinal tilt angle, the lateral tilt angle and the critical angle of the cargo box can be obtained through a large number of preliminary experiments and stored in the controller.

[0083] S150: Obtaining the flipping angle of the cargo box 200 relative to the vehicle frame 100 .

[0084] Specifically, the information can be obtained through a cargo box angle sensor 82 disposed in the cargo box 200 .

[0085] S160: Compare the flip angle with the critical angle of the cargo box.

[0086] If the flipping angle is not less than the critical angle of the cargo box, it indicates that the cargo box 200 is about to flip over. Although the lifting cylinder 3 will not be pulled out due to the presence of the reversing valve 5, the driver still needs to be reminded to operate with caution, so step S170 is executed.

[0087] S170: Issue a warning message.

[0088] The warning information may specifically be sound or light information. In the present embodiment, a display instrument 83 is further provided in the cab of the articulated dump truck, and the warning information is displayed by the display instrument 83 .

[0089] Optionally, in step S160, if the flipping angle is less than the critical angle of the cargo box, the process returns to step S150, that is, the flipping angle of the cargo box 200 relative to the frame 100 is re-acquired.

[0090] The cargo box overturning control method also includes a cargo box lowering control method, and the cargo box lowering control method includes the following steps.

[0091] S200: Confirm that the multi-way valve 4 is in the lowered position.

[0092] S210: Obtaining the flipping angle of the cargo box 200 relative to the vehicle frame 100 .

[0093] S220: Compare the flip angle with the floating critical angle.

[0094] The floating critical angle is generally a smaller value. When the flipping angle is equal to the floating critical angle, it indicates that the flipping angle of the cargo box 200 relative to the frame 100 is smaller and the cargo box 200 is about to contact the frame 100 .

[0095] If the flipping angle is not greater than the floating critical angle, it indicates that the cargo box 200 is about to contact the vehicle frame 100, and step S230 is executed.

[0096] S230: Control the multi-way valve 4 to move to a floating position.

[0097] In this way, the cargo box 200 can be controlled to descend slowly to avoid collision between the cargo box 200 and the vehicle frame 100 .

[0098] Optionally, in step S220, if the flipping angle is greater than the floating critical angle, it indicates that the cargo box 200 is still far away from the frame 100 at this time, and then the process returns to step S210 to re-acquire the flipping angle of the cargo box 200 relative to the frame 100.

[0099] In the cargo box flipping control method provided in this embodiment, during the process of the cargo box 200 rising or falling, the multi-way valve 4 can be controlled to move to the stop position at any time to keep the angle of the cargo box 200 relative to the frame 100 unchanged.

[0100] In addition, when the articulated dump truck is stopped for maintenance, the multi-way valve 4 can be always controlled to move to the lowered position or the floating position so that the cargo box 200 always has the force to move toward the frame 100 to ensure safety during maintenance.

[0101] Embodiment 3

[0102] This embodiment provides an articulated dump truck, comprising the cargo box turning device in the above-mentioned embodiment 1, and also comprising a vehicle frame 100 and a cargo box 200 hinged to the vehicle frame 100, wherein the cargo box turning device is disposed on the vehicle frame 100 and is used to drive the cargo box 200 to turn relative to the vehicle frame 100. In the cargo box turning device, when the turning angle of the cargo box 200 relative to the vehicle frame 100 is too large, the connection between the return oil pipeline 21 and the rod chamber 32 can be cut off by the reversing valve 5, thereby preventing the cargo box 200 from turning further and avoiding the cylinder pulling phenomenon.

[0103] Obviously, the above embodiments of the present invention are merely examples for clearly illustrating the present invention, and are not intended to limit the embodiments of the present invention. For those skilled in the art, various obvious changes, readjustments and substitutions can be made without departing from the protection scope of the present invention. It is not necessary and impossible to list all the embodiments here. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the claims of the present invention.

Claims

1. A cargo box flipping device, arranged on the vehicle frame (100) and used to drive the cargo box (200) to flip relative to the vehicle frame (100); It is characterized in that The cargo box turning device comprises: A pressure oil source (1), the output end of which is connected to an oil supply pipeline (11); An oil tank (2) connected to an oil return pipeline (21); A lifting cylinder (3) having a piston rod for driving the cargo box (200) to move, the piston rod dividing the inner cavity of the lifting cylinder (3) into a rodless cavity (31) and a rod cavity (32); The multi-way valve (4) is capable of moving in a set direction and has an ascending position and a descending position. The ascending position is provided with a reversing valve (5). When the multi-way valve (4) is in the ascending position, the oil supply pipeline (11) is connected to the rodless chamber (31), and the oil supply pipeline (11) is connected to the first control end of the reversing valve (5). The reversing valve (5) is used to connect or disconnect the oil return pipeline (21) with the rod chamber (32). When the multi-way valve (4) is in the descending position, the oil supply pipeline (11) is connected to the rodless chamber (31). The rod chamber (32), the oil return pipeline (21) is connected to the rodless chamber (31); the second control end of the reversing valve (5) is connected to an elastic member (51); the reversing valve (5) is arranged inside the multi-way valve (4) and forms a first chamber (501) and a second chamber (502); the multi-way valve (4) has a pressure oil port (401) connected to the inner chamber of the oil supply pipeline (11), a first port (402) connected to the inner chamber of the oil return pipeline (21), and a second port (403) connected to the rod chamber (32).

2. The cargo box turning device according to claim 1, characterized in that: The reversing valve (5) has a connection position and a non-connection position. When the reversing valve (5) is in the connection position, the oil return pipeline (21) is connected to the rod chamber (32). When the reversing valve (5) is in the non-connection position, the oil return pipeline (21) is disconnected from the rod chamber (32). The oil in the oil supply pipeline (11) is used to drive the reversing valve (5) to move toward the connection position. The elastic member (51) is used to provide an elastic force to move the reversing valve (5) toward the non-connection position.

3. The cargo box turning device according to claim 1, characterized in that: The multi-way valve (4) can also move in a set direction and have a stop position. When the multi-way valve (4) is in the stop position, the oil supply pipeline (11) is disconnected from the rodless chamber (31) and the rod chamber (32), and the oil return pipeline (21) is disconnected from the rodless chamber (31) and the rod chamber (32).

4. The cargo box turning device according to claim 1, characterized in that: The multi-way valve (4) is also capable of moving in a set direction to have a floating position. When the multi-way valve (4) is in the floating position, the oil supply pipeline (11) is connected to the rod chamber (32) via a connecting pipeline, and the oil return pipeline (21) is connected to the rodless chamber (31) via a floating pipeline. The cross-sectional area of ​​the floating pipeline is smaller than the cross-sectional area of ​​the connecting pipeline.

5. The cargo box turning device according to any one of claims 1 to 4, characterized in that: It also includes a pilot oil source (6) and a pilot valve (7) connected to the pilot oil source (6), wherein the pilot valve (7) is used to connect or disconnect the control end of the multi-way valve (4) with the pilot oil source (6); when the control end of the multi-way valve (4) is connected to the pilot oil source (6), the pilot oil source (6) is used to drive the multi-way valve (4) to move in a set direction.

6. A method for controlling a cargo box overturning, characterized in that: By implementing the cargo box turning device according to any one of claims 1 to 5, the cargo box turning control method includes a cargo box rising control method, and the cargo box rising control method includes: S100: obtaining a longitudinal inclination angle of the vehicle frame (100) along the front-rear direction of the vehicle body and a lateral inclination angle along the left-right direction of the vehicle body; S110: comparing the longitudinal inclination angle with a first set angle, and comparing the lateral inclination angle with a second set angle; If the longitudinal tilt angle is not less than the first set angle, or the lateral tilt angle is not less than the second set angle, executing step S120; S120: Preventing the multi-way valve (4) from moving toward the rising position.

7. The method for controlling the cargo box overturning according to claim 6, characterized in that: In step S110, if the longitudinal tilt angle is smaller than the first set angle, or the lateral tilt angle is smaller than the second set angle, step S130 is executed; S130: confirming that the multi-way valve (4) is in the ascending position; S140: Obtaining a critical angle of the cargo box according to the longitudinal tilt angle and the lateral tilt angle; S150: Obtaining a flipping angle of the cargo box (200) relative to the vehicle frame (100); S160: Compare the flip angle with the critical angle of the cargo box; If the flipping angle is not less than the critical angle of the cargo box, executing step S170; S170: Issue a warning message.

8. The method for controlling the cargo box overturning according to claim 7, characterized in that: In step S160, if the flipping angle is less than the critical angle of the cargo box, return to step S150.

9. The method for controlling the overturning of a cargo box according to any one of claims 6 to 8, characterized in that: The multi-way valve (4) is also capable of moving in a set direction to have a floating position. When the multi-way valve (4) is in the floating position, the oil supply pipeline (11) is connected to the rod chamber (32) via a connecting pipeline, and the oil return pipeline (21) is connected to the rodless chamber (31) via a floating pipeline. The cross-sectional area of ​​the floating pipeline is smaller than the cross-sectional area of ​​the connecting pipeline. The cargo box overturning control method also includes a cargo box lowering control method, and the cargo box lowering control method includes: S200: confirming that the multi-way valve (4) is in a lowered position; S210: Obtaining a flipping angle of the cargo box (200) relative to the vehicle frame (100); S220: Compare the flip angle with the floating critical angle; If the flip angle is not greater than the floating critical angle, executing step S230; S230: Controlling the multi-way valve (4) to move to a floating position.

10. An articulated dump truck, characterized in that: It comprises a cargo box flipping device as claimed in any one of claims 1 to 5, and also comprises a frame (100) and a cargo box (200) hinged to the frame (100), wherein the cargo box flipping device is arranged on the frame (100) and is used to drive the cargo box (200) to flip relative to the frame (100).

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