Dumper container anti-falling device and hydraulic system thereof

Abstract

The invention provides a dump truck cargo box anti-falling device and a hydraulic system thereof, the dump truck cargo box anti-falling device comprises a cargo box, a frame, a first pin shaft and a lifting oil cylinder, the rear end of the cargo box is hinged to the frame through the first pin shaft, and the lifting oil cylinder is connected between the cargo box and the frame and used for driving the cargo box to overturn upwards or fall down; the invention relates to a cargo box, in particular to a forklift truck, which comprises a frame, a cargo box, a first ratchet and a second ratchet, the first ratchet is fixed on the cargo box, one end of the second ratchet is hinged with the frame, the other end of the second ratchet extends to a position above the second ratchet, and a ratchet oil cylinder and a tension spring which are arranged in parallel are further connected between the second ratchet and the frame. The ratchet oil cylinder is connected with the lifting oil cylinder in series, and the volume of the ratchet oil cylinder is smaller than that of the lifting oil cylinder.

Description

Technical Field

[0001] The present application relates to the technical field of dump trucks, and in particular to a dump truck cargo box anti-falling device and a hydraulic system thereof. Background Art

[0002] Mining dump trucks are mainly used to transport heavy objects such as rocks, ores or coal in open-pit mines, and travel back and forth between mining sites and unloading sites. They have the characteristics of heavy cargo box, large cargo box volume, and large load capacity. During the lifting process of the cargo box of a mining dump truck, if the hydraulic system fails and causes the cargo box to fall, it will not only cause serious impact and damage to the cargo box itself and other parts of the vehicle, but may also cause serious injuries or even death to personnel.

[0003] At present, there are two main reasons for the cargo box to fall. One is the oil cylinder fracture. The oil cylinder is the core component of the cargo box lifting system of the mining dump truck. It bears the entire weight of the cargo box and its cargo. If the oil cylinder breaks, it will directly cause the cargo box to lose support and fall quickly. The other is the hydraulic oil circuit failure. The oil circuit failure is mainly caused by oil pipe bursting or pipeline detachment. These failures will cause the oil circuit to lose pressure quickly, causing the cargo box to fall quickly.

[0004] Therefore, how to prevent the cargo box from falling due to cylinder breakage or hydraulic oil circuit failure and improve the stability and safety of mining dump trucks is a technical problem faced by technical personnel in this field. Summary of the invention

[0005] In order to solve the technical problems existing in the prior art, the first aspect of the present application provides a dump truck cargo box anti-falling device, including a cargo box, a frame, a first pin shaft and a lifting cylinder, the rear end of the cargo box is hinged to the frame through the first pin shaft, and the lifting cylinder is connected between the cargo box and the frame to drive the cargo box to flip upward or fall; it also includes a first ratchet and a second ratchet, the first ratchet is fixed on the cargo box, one end of the second ratchet is hinged to the frame, and the other end extends above the second ratchet, and a ratchet cylinder and a tension spring arranged in parallel are also connected between the second ratchet and the frame, wherein the ratchet cylinder is connected in series with the lifting cylinder and the volume of the ratchet cylinder is smaller than the volume of the lifting cylinder.

[0006] Furthermore, the anti-fall device also includes a speed sensor fixed on the second ratchet for detecting the relative movement speed between the first ratchet and the second ratchet, the speed sensor is connected to the vehicle controller, and the vehicle controller is connected to the control end of the ratchet cylinder. When the speed sensor detects that the relative movement speed between the first ratchet and the second ratchet is greater than a set threshold, the vehicle controller controls the release of the pressure of the ratchet cylinder, and the first ratchet and the second ratchet engage to lock the cargo box.

[0007] Furthermore, the first ratchet is an arc-shaped tooth plate, whose inner concave surface is provided with a first latching tooth, and the second ratchet is hinged to the frame through a second pin shaft, and whose outer convex surface is provided with a second latching tooth corresponding to the first latching tooth.

[0008] A second aspect of the present application provides a dump truck cargo box anti-falling hydraulic system, comprising an anti-falling device as described in any of the above items, and a hydraulic oil tank, a hydraulic pump, a first reversing valve and a lifting cylinder connected in sequence, the control end of the hydraulic pump is connected to a first air valve, the control end of the first reversing valve is connected to a lifting limit valve and a second air valve, the control ends of the first air valve and the second air valve are connected to a operating device, and the output end of the first reversing valve is also connected to the ratchet cylinder.

[0009] Furthermore, a first solenoid valve is connected between the ratchet cylinder and the output end of the first reversing valve, and a second solenoid valve is connected between the ratchet cylinder and the hydraulic oil tank, wherein the first solenoid valve is a normally open solenoid hydraulic valve and the second solenoid valve is a normally closed solenoid hydraulic valve; the control ends of the first solenoid valve and the second solenoid valve are connected to the vehicle controller.

[0010] Furthermore, the first reversing valve is a three-position three-way hydraulic valve, and the first reversing valve is connected to a relief valve.

[0011] Furthermore, the first air valve is a two-position three-way air valve, the second air valve is a three-position four-way air valve, and the operating device is a rocker switch.

[0012] Compared with the prior art, the beneficial effects of this application are: 1. In the dump truck cargo box anti-falling device of the present application, the oil circuits of the ratchet cylinder and the lifting cylinder are connected in series. When the lifting cylinder loses pressure, the ratchet cylinder loses pressure at the same time. The second ratchet moves forward under the action of gravity and the tension of the tension spring and engages with the first ratchet to lock the cargo box and prevent the cargo box from falling, thereby greatly improving the stability and safety of the dump truck.

[0013] 2. The second ratchet of the dump truck cargo box anti-fall device of the present application is provided with a speed sensor. When the relative moving speed between the first ratchet and the second ratchet is greater than the preset threshold, the vehicle controller controls the pressure oil in the ratchet cylinder to flow out through the control end of the ratchet cylinder, and the ratchet cylinder loses pressure at the same time. Under the action of gravity and the tension of the tension spring, the second ratchet moves forward and meshes with the first ratchet to lock the cargo box, realizing a double protection mechanism and providing a more comprehensive and reliable anti-fall protection for the dump truck. It not only improves the stability and safety of the dump truck, but also reduces the risk caused by the cargo box falling. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1This is a schematic diagram of the structure of the dump truck cargo box anti-falling device of the present application; Figure 2 This is a schematic diagram of the structure of the dump truck cargo box anti-falling device of the present application; Figure 3 The hydraulic principle diagram of the anti-fall hydraulic system of the dump truck cargo box of this application; In the figure: 1. Cargo box; 2. Vehicle frame; 3. First pin shaft; 4. First ratchet; 5. Second ratchet; 6. Second pin shaft; 7. Ratchet cylinder; 8. Tension spring; 9. Speed ​​sensor; 10. First air valve; 11. Second air valve; 12. Hydraulic pump; 13. First reversing valve; 14. Lifting cylinder; 15. Lifting limit valve; 16. First solenoid valve; 17. Second solenoid valve; 18. Vehicle controller; 19. Hydraulic oil tank. DETAILED DESCRIPTION

[0015] In order to facilitate the understanding of the present application, the technical solutions in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0016] The present application is described in detail below. In the following paragraphs, different aspects of the embodiments are defined in more detail. Each aspect defined in this way can be combined with any other aspect or aspects, unless it is clearly stated that it cannot be combined. In particular, any feature that is considered to be preferred or advantageous can be combined with one or more other features that are considered to be preferred or advantageous.

[0017] The words "first", "second" and similar words used in this application do not indicate any order, quantity or importance, but are only used to distinguish different parts. The words "include" or "comprise" and similar words mean that the elements before the word include the elements listed after the word, and do not exclude the possibility of including other elements.

[0018] In the description of the present application, it should be understood that the terms "inside", "outside", "up", "down", "left" and "right" etc. indicating directions or positional relationships are based on the directions or positional relationships shown in the accompanying drawings and are only for the convenience of describing the present application. They do not indicate or imply that the device referred to must have a specific direction, be constructed and operated in a specific direction. Therefore, they should not be understood as limiting the scope of protection of the present application.

[0019] refer to Figure 1 to Figure 2As shown, the present application discloses a dump truck cargo box anti-falling device, including a cargo box 1, a frame 2, a first pin 3 and a lifting cylinder 14, the rear end of the cargo box 1 is hinged to the frame 2 through the first pin 3, and the lifting cylinder 14 is connected between the cargo box 1 and the frame 2 to drive the cargo box 1 to flip upward or fall. The anti-falling device also includes a first ratchet 4 and a second ratchet 5, the first ratchet 4 is fixed on the cargo box 1, one end of the second ratchet 5 is hinged to the frame 2, and the other end extends above the second ratchet 5, and a ratchet cylinder 7 and a tension spring 8 arranged in parallel are also connected between the second ratchet 5 and the frame 2. Among them, the two ends of the ratchet cylinder 7 are respectively hinged to the second ratchet 5 and the frame 2, the two ends of the tension spring 8 are respectively hinged to the second ratchet 5 and the frame 2, the ratchet cylinder 7 is connected in series with the lifting cylinder 14, and the volume of the ratchet cylinder 7 is smaller than the volume of the lifting cylinder 14. When the hydraulic system fails and the lifting cylinder 14 loses pressure, the ratchet cylinder 7 loses pressure at the same time, and the ratchet cylinder 7 can no longer support the second ratchet 5. The second ratchet 5 is pressed downward by gravity and the tension of the tension spring 8, and the second ratchet 5 engages with the first ratchet 4 to lock the cargo box 1 and prevent the cargo box 1 from falling. The series connection of the oil circuits of the ratchet cylinder 7 and the lifting cylinder 14 ensures that the cargo box 1 will not fall due to the loss of pressure in the lifting cylinder 14 when the hydraulic system fails. The stability and safety of the dump truck are greatly improved.

[0020] In some embodiments, the first ratchet 4 is an arc-shaped tooth plate, and the center of the arc-shaped tooth plate coincides with the hinge point between the cargo box 1 and the frame 2. The first ratchet 4 has a first latching tooth on its inner concave surface, and the second ratchet 5 is hinged to the frame 2 through a second pin 6, and its outer convex surface has a second latching tooth corresponding to the first latching tooth. The arc-shaped tooth plate can produce a more uniform stress distribution when subjected to force, thereby avoiding local overload and damage.

[0021] In some embodiments, the anti-fall device further includes a speed sensor 9 fixed on the second ratchet 5 for detecting the relative movement speed between the first ratchet 4 and the second ratchet 5. The speed sensor 9 is connected to the vehicle controller 18, and the vehicle controller 18 is connected to the control end of the ratchet cylinder 7. When the relative movement speed between the first ratchet 4 and the second ratchet 5 is greater than a preset threshold value, the vehicle controller 18 controls the pressure oil in the ratchet cylinder 7 to flow out through the control end of the ratchet cylinder 7, and the second ratchet 5 is pressed downward under the action of gravity and the tension of the tension spring 8, and the second ratchet 5 is engaged with the first ratchet 4 to lock the cargo box 1 to prevent the cargo box 1 from falling.

[0022] In some embodiments, the speed sensor 9 is a Hall sensor, and the working principle of the Hall sensor is based on the Hall effect. A steel grid scale tape is provided on the side of the first ratchet 4, and the speed sensor 9 is fixed on the second ratchet 5. When the cargo box 1 is turned up or falls, the moving track of the detection head of the speed sensor 9 coincides with the grid scale tape. The gap between the detection head of the speed sensor 9 and the steel grid scale tape is 0.5-20mm. When the steel grid scale tape passes through the detection head of the speed sensor 9, it cuts the magnetic field of the detection head and forms an electrical pulse. The frequency of the pulse signal can be converted into the movement speed of the steel grid scale tape.

[0023] In some embodiments, the speed sensor 9 is a photoelectric speed sensor, a striped sticker is provided on the side of the first ratchet 4, the light and dark stripes form a photoelectric signal, and the frequency of the photoelectric signal is converted into the speed of the striped sticker.

[0024] The present application also discloses a dump truck cargo box anti-falling hydraulic system, comprising the above-mentioned anti-falling device, and a hydraulic oil tank 19, a hydraulic pump 12, a first reversing valve 13 and a lifting cylinder 14 connected in sequence, the control end of the hydraulic pump 12 is connected to the first air valve 10, the control end of the first reversing valve 13 is connected to the lifting limit valve 15 and the second air valve 11, the control ends of the first air valve 10 and the second air valve 11 are connected to a control device, the output end of the first reversing valve 13 is also connected to the ratchet cylinder 7, and the volume of the rodless chamber of the ratchet cylinder 7 is much smaller than the volume of the rodless chamber of the lifting cylinder 14.

[0025] Preferably, the first reversing valve 13 is a three-position three-way hydraulic valve, and the first reversing valve 13 is connected to a relief valve. The first air valve 10 is a two-position three-way air valve, the second air valve 11 is a three-position four-way air valve, and the operating device is a rocker switch. When it is necessary to lift the cargo box 1, the cab rocker switch is pressed, and the rocker switch controls the first air valve 10 to open through the circuit, and the first air valve 10 connects the air source and the control end of the hydraulic pump 12, and the hydraulic pump 12 engages with the power source to output pressure oil to the first reversing valve 13. After the first air valve 10 is opened, the control end of the second air valve 11 is energized, and the second air valve 11 connects the air source and the control end of the first reversing valve 13, and the first reversing valve 13 is switched to connect the hydraulic pump 12 and the lifting cylinder 14, and the rodless chamber of the lifting cylinder 14 enters oil to lift the cargo box 1 upward. When the cargo box 1 is lifted to a predetermined height, the lifting limit valve 15 is closed, and the first reversing valve 13 switches to cut off the oil circuit between the hydraulic pump 12 and the lifting cylinder 14. The pressure oil output by the hydraulic pump 1 flows back to the hydraulic oil tank 19 through the first reversing valve 13, and the cargo box 1 maintains the predetermined lifting height. The output end of the first reversing valve 13 is also connected to the ratchet cylinder 7. When the hydraulic pump 12 supplies oil to the lifting cylinder 14 through the first reversing valve 13, the first reversing valve 13 also supplies oil to the ratchet cylinder 7 at the same time. Since the volume of the rodless chamber of the ratchet cylinder 7 is much smaller than the volume of the rodless chamber of the lifting cylinder 14, the pressure oil required by the ratchet cylinder 7 is much smaller than the pressure oil required by the lifting cylinder 14, and the piston rod of the ratchet cylinder 7 reaches the predetermined stroke first. The ratchet cylinder 7 overcomes the gravity of the second ratchet 5 and the tension of the tension spring 8 to lift the second ratchet 5 upward, so that the second ratchet 5 is out of contact with the first ratchet 4. At this time, the anti-fall device does not affect the lifting of the cargo box 1.

[0026] When the oil circuit of the lifting cylinder 14 or the first reversing valve 13 is broken, the pressure oil in the rodless chambers of the lifting cylinder 14 and the ratchet cylinder 7 flows out at the same time. Since the volume of the rodless chamber of the ratchet cylinder 7 is much smaller than that of the rodless chamber of the lifting cylinder 14, the time required for the ratchet cylinder 7 to release the oil is shorter, and the ratchet cylinder 7 cannot support the second ratchet 5. The second ratchet 5 is pressed downward under the action of gravity and the tension of the tension spring 8. The second ratchet 5 engages with the first ratchet 4 to lock the cargo box 1 and prevent the cargo box 1 from falling. The series connection of the oil circuits of the ratchet cylinder 7 and the lifting cylinder 14 ensures that the cargo box 1 will not fall due to the loss of pressure in the lifting cylinder 14 when the hydraulic system fails. The stability and safety of the dump truck are greatly improved.

[0027] When the cargo box 1 needs to be lowered, the second air valve 11 is manually controlled to change position and drive the first reversing valve 13 to change direction. The pressure oil output by the hydraulic pump 1 flows back to the hydraulic oil tank 19 through the first reversing valve 13. At the same time, the gravity of the cargo box 1 drives the hydraulic oil in the rodless chamber of the lifting cylinder 14 to flow back to the hydraulic oil tank 19, and the cargo box 1 is lowered.

[0028] In some embodiments, a first solenoid valve 16 is connected between the oil inlet end of the ratchet cylinder 7 and the output end of the first reversing valve 13, and a second solenoid valve 17 is connected between the oil inlet end of the ratchet cylinder 7 and the hydraulic oil tank 19, wherein the first solenoid valve 16 is a normally open solenoid hydraulic valve and the second solenoid valve 17 is a normally closed solenoid hydraulic valve; the control ends of the first solenoid valve 16 and the second solenoid valve 17 are connected to the vehicle controller 18, and the vehicle controller 18 is connected to the speed sensor 9.

[0029] When the hydraulic pump 12 supplies oil to the lifting cylinder 14 through the first reversing valve 13, the first reversing valve 13 simultaneously supplies oil to the ratchet cylinder 7 through the first solenoid valve 16. The ratchet cylinder 7 overcomes the gravity of the second ratchet 5 and the tension of the tension spring 8 to lift the second ratchet 5 upward, so that the second ratchet 5 is out of contact with the first ratchet 4. At this time, the anti-falling device does not affect the lifting of the cargo box 1.

[0030] When the hydraulic oil circuit is normal and other reasons cause the cargo box 1 to fall rapidly, the speed sensor 9 detects that the relative movement speed between the first ratchet 4 and the second ratchet 5 is greater than a preset threshold value, and transmits the information to the vehicle controller 18. The vehicle controller 18 controls the first solenoid valve 16 to close and the second solenoid valve 17 to open. The pressure oil in the ratchet cylinder 7 flows back to the hydraulic oil tank 19 through the second solenoid valve 17. The second ratchet 5 is pressed downward by gravity and the tension of the tension spring 8. The second ratchet 5 engages with the first ratchet 4 to lock the cargo box 1 and prevent it from falling.

[0031] The above shows and describes the basic principles, main features and advantages of the present application. Those skilled in the art should understand that the present application is not limited by the above embodiments. The above embodiments and descriptions are only for explaining the principles of the present application. Without departing from the spirit and scope of the present application, the present application may have various changes and improvements, which fall within the scope of the present application to be protected. The scope of protection claimed in the present application is defined by the attached claims and their equivalents.

Claims

1. A dump truck cargo box anti-falling device, comprising a cargo box (1), a frame (2), a first pin shaft (3) and a lifting cylinder (14), wherein the rear end of the cargo box (1) is hinged to the frame (2) via the first pin shaft (3), and the lifting cylinder (14) is connected between the cargo box (1) and the frame (2) to drive the cargo box (1) to flip upward or fall downward; characterized in that: The vehicle also comprises a first ratchet (4) and a second ratchet (5), wherein the first ratchet (4) is fixed on the cargo box (1), one end of the second ratchet (5) is hinged to the frame (2), and the other end extends above the second ratchet (5), and a ratchet cylinder (7) and a tension spring (8) arranged in parallel are connected between the second ratchet (5) and the frame (2), wherein the ratchet cylinder (7) is connected in series with the lifting cylinder (14) and the volume of the ratchet cylinder (7) is smaller than the volume of the lifting cylinder (14).

2. The dump truck cargo box anti-falling device according to claim 1, characterized in that: The anti-fall device further comprises a speed sensor (9) fixed on the second ratchet (5) for detecting the relative moving speed between the first ratchet (4) and the second ratchet (5); the speed sensor (9) is connected to a vehicle controller (18); the vehicle controller (18) is connected to a control end of the ratchet cylinder (7); when the speed sensor (9) detects that the relative moving speed between the first ratchet (4) and the second ratchet (5) is greater than a set threshold, the vehicle controller (18) controls the release of the pressure of the ratchet cylinder (7), and the first ratchet (4) and the second ratchet (5) engage to lock the cargo box (1).

3. The dump truck cargo box anti-falling device according to claim 1, characterized in that: The first ratchet (4) is an arc-shaped tooth plate, and a first latching tooth is provided on its inner concave surface; the second ratchet (5) is hinged to the frame (2) via a second pin shaft (6), and a second latching tooth corresponding to the first latching tooth is provided on its outer convex surface.

4. A dump truck cargo box anti-fall hydraulic system, characterized in that: The anti-fall device comprises the anti-fall device as claimed in any one of claims 1 to 3, and a hydraulic oil tank (19), a hydraulic pump (12), a first reversing valve (13) and a lifting cylinder (14) connected in sequence, wherein the control end of the hydraulic pump (12) is connected to a first air valve (10), the control end of the first reversing valve (13) is connected to a lifting limit valve (15) and a second air valve (11), the control ends of the first air valve (10) and the second air valve (11) are connected to a control device, and the output end of the first reversing valve (13) is also connected to the ratchet cylinder (7).

5. The dump truck cargo box anti-fall hydraulic system according to claim 4, characterized in that: A first solenoid valve (16) is connected between the ratchet cylinder (7) and the output end of the first reversing valve (13), and a second solenoid valve (17) is connected between the ratchet cylinder (7) and the hydraulic oil tank (19), wherein the first solenoid valve (16) is a normally open solenoid hydraulic valve, and the second solenoid valve (17) is a normally closed solenoid hydraulic valve; control ends of the first solenoid valve (16) and the second solenoid valve (17) are connected to a vehicle controller (18).

6. The dump truck cargo box anti-fall hydraulic system according to claim 4, characterized in that: The first reversing valve (13) is a three-position three-way hydraulic valve, and the first reversing valve (13) is connected to a relief valve.

7. The dump truck cargo box anti-fall hydraulic system according to claim 4, characterized in that: The first air valve (10) is a two-position three-way air valve, the second air valve (11) is a three-position four-way air valve, and the operating device is a rocker switch.

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