Valve group, spreader leveling hydraulic system, control method and device, and crane

Abstract

The present invention discloses a valve group, a sling leveling hydraulic system, a control method and device thereof, and a crane. The valve group includes an electromagnetic reversing valve, an electromagnetic valve, a pressure reducing relief valve, an electric proportional reversing valve, a two-way balancing valve, a first one-way throttle valve, a second one-way throttle valve, a one-way valve, a control valve group A port, a control valve group B port, a control valve group P port, and a control valve group T port. The electromagnetic valve and the one-way valve are connected in series and then connected in parallel with the pressure reducing relief valve. The oil inlet P port of the electric proportional reversing valve is connected to the control valve group P port, and the oil return T port of the electric proportional reversing valve is connected to the control valve group T port. The sling of the present invention is adaptive to the amplitude change of the boom, realizing multi-stage or stepless leveling of the sling leveling hydraulic system. It can passively level to meet the working conditions and actively level to adapt to the diversity of boom speed changes. It can realize two-way locking of the leveling cylinder, playing a supporting role for the sling and the hoisted object.

Description

Technical Field

[0001] The present invention relates to the technical field of cranes, and in particular discloses a valve group, a spreader leveling hydraulic system, a control method and device thereof, and a crane. Background Art

[0002] When certain cranes with spreaders adjust their boom height, the angle between the spreader and the boom also changes with height. To meet lifting requirements, the spreader must automatically adjust its angle at a speed that matches the boom's amplitude change, ensuring the spreader remains horizontal.

[0003] The patent document with Chinese patent publication number CN110282548A discloses an anti-sway hydraulic system, an anti-sway device and a reach crane. Leveling and anti-swaying are achieved through a speed regulating valve. Although the speed is not affected by load changes, it is difficult to meet the requirements of different boom speed conditions.

[0004] Chinese patent publication CN106865413A discloses a valve block for automatic leveling of a container reach stacker spreader. The valve block can achieve rapid leveling when the spreader is unloaded, but is difficult to meet the leveling requirements under different load conditions.

[0005] Chinese patent publication number CN215364620U discloses a damping control oil circuit for a sling and a hoisting device with a damping control function. Damping adjustment is time-consuming and labor-intensive, and is difficult to adapt to leveling of various loads.

[0006] Therefore, the existing hydraulic system of the spreader is time-consuming to adjust the damping, and is affected by the load size, making it difficult to simultaneously meet the working conditions of different loads; and the leveling and anti-swaying through the speed control valve, although the speed does not change with the load, is difficult to meet the working conditions of different boom speeds, which is a technical problem that needs to be solved urgently. Summary of the Invention

[0007] The present invention provides a valve group, a spreader leveling hydraulic system, a control method and device thereof, and a crane, aiming to solve the technical problems existing in the existing spreader hydraulic system, namely, that damping adjustment is time-consuming and is affected by the load size, making it difficult to simultaneously meet the working conditions of different loads; and that leveling and anti-swaying through a speed regulating valve, although the speed does not change with load changes, is difficult to meet the working conditions of different boom speeds.

[0008] One aspect of the present invention relates to a valve group, including an electromagnetic reversing valve, an electromagnetic valve, a pressure reducing relief valve, an electric proportional reversing valve, a two-way balancing valve, a first one-way throttle valve, a second one-way throttle valve, a one-way valve, a control valve group A port, a control valve group B port, a control valve group P port and a control valve group T port, the electromagnetic valve and the one-way valve are connected in series and then connected in parallel with the pressure reducing relief valve; the oil inlet P port of the electric proportional reversing valve is connected to the control valve group P port, and the oil return T port of the electric proportional reversing valve is connected to the control valve group T port; the working A port of the electric proportional reversing valve is connected to the control valve through the two-way balancing valve. The A port of the electromagnetic reversing valve is connected to the A port of the control valve group, and the working B port of the electric proportional reversing valve is connected to the B port of the control valve group through the two-way balancing valve; the oil outlet of the pressure reducing relief valve is connected to the T port of the control valve group, and the control oil port of the pressure reducing relief valve is connected to the P port of the control valve group; the oil inlet of the pressure reducing relief valve is divided into two paths, one path is connected to the P port of the electromagnetic reversing valve through the first one-way throttle valve; the other path is connected to the T port of the electromagnetic reversing valve after passing through the second one-way throttle valve; the A port of the electromagnetic reversing valve is connected to the A port of the control valve group, and the B port of the electromagnetic reversing valve is connected to the B port of the control valve group.

[0009] Another aspect of the present invention relates to a spreader leveling hydraulic system, comprising the above-mentioned valve group and a leveling oil cylinder connected to the valve group.

[0010] Furthermore, the leveling cylinder includes a first leveling cylinder and a second leveling cylinder, and the A port of the control valve group is respectively connected to the rodless chamber of the first leveling cylinder and the rodless chamber of the second leveling cylinder; the B port of the control valve group is respectively connected to the rod chamber of the first leveling cylinder and the rod chamber of the second leveling cylinder.

[0011] Furthermore, the spreader leveling hydraulic system also includes an oil tank, which is connected to the T port of the control valve group.

[0012] Furthermore, the spreader leveling hydraulic system also includes a power device, which is connected to the oil tank through a delivery pipeline.

[0013] Furthermore, the power unit adopts an oil pump.

[0014] Furthermore, the spreader leveling hydraulic system also includes an angle detection device and a controller. The angle detection device is arranged between the spreader and the boom. The controller is electrically connected to the angle detection device, the electromagnetic reversing valve, the electromagnetic valve, and the electric proportional reversing valve respectively. When the angle detection device detects that the angle between the spreader and the boom reaches a set value, it controls the electromagnetic reversing valve, the electromagnetic valve and the electric proportional reversing valve to perform bidirectional locking on the leveling cylinder, prompting the leveling cylinder to maintain a certain posture, thereby ensuring that the spreader of the crane is always in a horizontal state.

[0015] Another aspect of the present invention relates to a method for controlling a spreader leveling hydraulic system, which is applied to the above-mentioned spreader leveling hydraulic system and comprises the following steps:

[0016] Passive leveling steps of the spreader: When the lifting machinery with the spreader is in motion, when the output pressure of the pressure reducing relief valve is higher than the set pressure, the hydraulic oil flows back to the oil tank through the solenoid valve and the one-way valve to ensure that the oil pressure flowing into the leveling cylinder does not exceed the set value; when the crane stops moving forward, the hydraulic oil in the rod chamber of the leveling cylinder is damped by the throttle port of the second one-way throttle valve, so that the leveling cylinder cannot be extended or extends slowly. At the same time, the hydraulic oil flows into the first one-way throttle valve through the pressure reducing relief valve and then flows through the electromagnetic reversing valve. The valves enter the rodless chambers of the first and second leveling cylinders respectively to prevent the rodless chambers of the leveling cylinders from being sucked empty. When the crane stops in reverse, the hydraulic oil in the rodless chambers of the leveling cylinders is damped by the throttle port of the first one-way throttle valve, so that the leveling cylinders cannot be retracted or retract slowly, so that the spreader remains in a horizontal state. At the same time, the hydraulic oil flows through the pressure reducing relief valve into the second one-way throttle valve and then flows through the electromagnetic reversing valve into the rod chambers of the first and second leveling cylinders to prevent the rod chambers of the leveling cylinders from being sucked empty.

[0017] The steps for active leveling of the spreader are as follows: when the boom is rapidly lifted, the angle detection device detects that the angle between the spreader and the boom is greater than a certain angle, the electric proportional reversing valve, the electromagnetic reversing valve and the solenoid valve are energized, and the hydraulic oil output by the oil pump flows from the electric proportional reversing valve into the two-way balancing valve through the A port of the control valve group and enters the rodless chamber of the leveling cylinder. The leveling cylinder is rapidly extended and the two-way balancing valve is opened at the same time. The hydraulic oil in the rod chamber of the leveling cylinder flows through the B port of the control valve group through the two-way balancing valve, enters the electric proportional reversing valve and flows back to the oil tank; when the boom is rapidly lowered, the angle detection device detects that the angle between the spreader and the boom is greater than a certain angle, the electric proportional reversing valve and the electromagnetic reversing valve are energized, and the hydraulic oil output by the oil pump flows from the electric proportional reversing valve into the two-way balancing valve through the B port of the control valve group and enters the rod chamber of the leveling cylinder. The leveling cylinder is retracted and the two-way balancing valve is opened at the same time. The hydraulic oil in the rod chamber of the leveling cylinder flows through the A port of the control valve group through the two-way balancing valve, enters the electric proportional reversing valve and flows back to the oil tank;

[0018] The steps for bidirectional locking of the leveling cylinder are as follows: when the angle between the spreader and the boom reaches the set value, the electric proportional reversing valve is not energized and the electromagnetic reversing valve is energized, cutting off the hydraulic oil from entering the leveling cylinder, and the bidirectional balancing valve locks the rod chamber and rodless chamber of the leveling cylinder.

[0019] Another aspect of the present invention relates to a spreader leveling hydraulic system control device, which is applied to the spreader leveling hydraulic system as described above, comprising:

[0020] The passive leveling module of the spreader is used for the lifting machinery with spreaders. When the output pressure of the pressure reducing relief valve is higher than the set pressure, the hydraulic oil flows back to the oil tank through the solenoid valve and the one-way valve to ensure that the oil pressure flowing into the leveling cylinder does not exceed the set value; when the crane stops moving forward, the hydraulic oil in the rod chamber of the leveling cylinder is damped by the throttle port of the first one-way throttle valve, so that the leveling cylinder cannot be extended or extends slowly. At the same time, the hydraulic oil flows through the pressure reducing relief valve into the second one-way throttle valve and then flows through the electromagnetic valve. The directional valves enter the rodless chambers of the first and second leveling cylinders respectively to prevent the rodless chambers of the leveling cylinders from being sucked empty. When the crane stops in reverse, the hydraulic oil in the rodless chambers of the leveling cylinders is damped by the throttle port of the second one-way throttle valve, so that the leveling cylinders cannot be retracted or retract slowly, so that the spreader remains in a horizontal state. At the same time, the hydraulic oil flows into the first one-way throttle valve through the pressure reducing relief valve and then flows through the electromagnetic reversing valve into the rod chambers of the first and second leveling cylinders to prevent the rod chambers of the leveling cylinders from being sucked empty.

[0021] The active leveling module of the spreader is used for: when the boom is rapidly raised, the angle detection device detects that the angle between the spreader and the boom is greater than a certain angle, the electric proportional reversing valve, the electromagnetic reversing valve and the solenoid valve are energized, and the hydraulic oil output by the oil pump flows from the electric proportional reversing valve into the two-way balancing valve through the A port of the control valve group and enters the rodless chamber of the leveling cylinder. The leveling cylinder is rapidly extended, and the two-way balancing valve is opened at the same time. The hydraulic oil in the rod chamber of the leveling cylinder flows through the B port of the control valve group, through the two-way balancing valve, into the electric proportional reversing valve and flows back to the oil tank; when the boom is rapidly lowered, the angle detection device detects that the angle between the spreader and the boom is greater than a certain angle, the electric proportional reversing valve and the electromagnetic reversing valve are energized, and the hydraulic oil output by the oil pump flows from the electric proportional reversing valve into the two-way balancing valve through the B port of the control valve group and enters the rod chamber of the leveling cylinder. The leveling cylinder is retracted, and the two-way balancing valve is opened at the same time. The hydraulic oil in the rodless chamber of the leveling cylinder flows through the A port of the control valve group, through the two-way balancing valve, into the electric proportional reversing valve and flows back to the oil tank;

[0022] The two-way locking module of the leveling cylinder is used to cut off the hydraulic oil from entering the leveling cylinder when the angle between the spreader and the boom reaches the set value. The electric proportional reversing valve is de-energized and the electromagnetic reversing valve is energized, thereby locking the rod chamber and rodless chamber of the leveling cylinder with the two-way balancing valve.

[0023] Another aspect of the present invention relates to a crane comprising the above-mentioned spreader leveling hydraulic system.

[0024] The beneficial effects achieved by the present invention are:

[0025] The present invention provides a valve group, a sling leveling hydraulic system, a control method and device thereof, and a crane. The valve group adopts an electromagnetic reversing valve, an electromagnetic valve, a pressure reducing relief valve, an electric proportional reversing valve, a two-way balancing valve, a first one-way throttle valve, a second one-way throttle valve, a one-way valve, a control valve group A port, a control valve group B port, a control valve group P port, and a control valve group T port. The electromagnetic valve and the one-way valve are connected in series and then connected in parallel with the pressure reducing relief valve; the oil inlet P port of the electric proportional reversing valve is connected to the control valve group P port, and the oil return T port of the electric proportional reversing valve is connected to the control valve group T port; the working A port of the electric proportional reversing valve is connected to the control valve group B port. The oil inlet of the pressure reducing relief valve is divided into two routes, one route is connected to the P port of the electromagnetic reversing valve through the first one-way throttle valve; the other route is connected to the T port of the electromagnetic reversing valve after passing through the second one-way throttle valve; the A port of the electromagnetic reversing valve is connected to the A port of the control valve group, and the B port of the electromagnetic reversing valve is connected to the B port of the control valve group. The present invention provides a valve group, a spreader leveling hydraulic system, a control method and device thereof, and a crane. The spreader adapts to the amplitude change of the boom to realize the spreader leveling hydraulic system of multi-stage or stepless leveling; it can passively level to meet the working conditions, and actively level to adapt to the diversity of boom speed changes; it can realize two-way locking of the leveling cylinder, and play a supporting role for the spreader and the suspended object. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 A schematic diagram of the hydraulic principle of an embodiment of a valve group provided by the present invention;

[0027] Figure 2 This is a schematic diagram of the hydraulic principle of an embodiment of the spreader leveling hydraulic system provided by the present invention.

[0028] Description of Figure Numbers:

[0029] 10. Solenoid reversing valve; 20. Solenoid valve; 30. Pressure reducing relief valve; 40. Electric proportional reversing valve; 50. Two-way balancing valve; 61. First one-way throttle valve; 62. Second one-way throttle valve; 70. One-way valve; 81. First leveling cylinder; 82. Second leveling cylinder. DETAILED DESCRIPTION

[0030] In order to better understand the above technical solution, the above technical solution will be described in detail below with reference to the accompanying drawings and specific implementation methods.

[0031] As shown in the figure, the first embodiment of the present invention proposes a valve group, including a solenoid reversing valve 10, a solenoid valve 20, a pressure reducing relief valve 30, an electric proportional reversing valve 40, a two-way balancing valve 50, a first one-way throttle valve 61, a second one-way throttle valve 62, a one-way valve 70, a control valve group A port, a control valve group B port, a control valve group P port and a control valve group T port. The solenoid valve 20 and the one-way valve 70 are connected in series and then connected in parallel with the pressure reducing relief valve 30; the oil inlet P port of the electric proportional reversing valve 40 is connected to the control valve group P port, and the oil return T port of the electric proportional reversing valve 40 is connected to the control valve group T port; the working A port of the electric proportional reversing valve 40 is connected through a two-way balancing valve. Valve 50 is connected to port A of the control valve group, and the working port B of the electric proportional reversing valve 40 is connected to port B of the control valve group through the two-way balancing valve 50; the oil outlet of the pressure reducing relief valve 30 is connected to port T of the control valve group, and the control oil port of the pressure reducing relief valve 30 is connected to port P of the control valve group; the oil inlet of the pressure reducing relief valve 30 is divided into two paths, one path is connected to port P of the electromagnetic reversing valve 10 through the first one-way throttle valve 61; the other path is connected to port T of the electromagnetic reversing valve 10 after passing through the second one-way throttle valve 62; port A of the electromagnetic reversing valve 10 is connected to port A of the control valve group, and port B of the electromagnetic reversing valve 10 is connected to port B of the control valve group.

[0032] Please see Figure 2 , Figure 2 This is a schematic diagram of the hydraulic principle of an embodiment of the sling leveling hydraulic system provided by the present invention. In this embodiment, the sling leveling hydraulic system includes the above-mentioned valve group and a leveling cylinder connected to the valve group. Specifically, the leveling cylinder includes a first leveling cylinder 81 and a second leveling cylinder 82. The A port of the control valve group is connected to the rodless cavity of the first leveling cylinder 81 and the rodless cavity of the second leveling cylinder 82, respectively; the B port of the control valve group is connected to the rod cavity of the first leveling cylinder 81 and the rod cavity of the second leveling cylinder 82, respectively. The sling leveling hydraulic system also includes an oil tank and a power unit. The oil tank is connected to the T port of the control valve group. The power unit is connected to the oil tank through a delivery pipeline. In this embodiment, the power unit preferably adopts an oil pump.

[0033] Further, see Figure 1 and Figure 2 The sling leveling hydraulic system provided by the present invention also includes an angle detection device and a controller. The angle detection device is arranged between the sling and the boom. The controller is electrically connected to the angle detection device, the electromagnetic reversing valve 10, the electromagnetic valve 20, and the electric proportional reversing valve 40 respectively. When the angle detection device detects that the angle between the sling and the boom reaches a set value, it controls the electromagnetic reversing valve 10, the electromagnetic valve 20 and the electric proportional reversing valve 40 to perform bidirectional locking on the leveling cylinder, so as to prompt the leveling cylinder to maintain a certain posture and ensure that the sling of the crane is always in a horizontal state.

[0034] Please see Figure 1 and Figure 2Another aspect of the present invention relates to a method for controlling a spreader leveling hydraulic system, which is applied to the above-mentioned spreader leveling hydraulic system and comprises the following steps:

[0035] Step S100, the sling passive leveling step, when the lifting machinery with the sling is in motion, when the output pressure of the pressure reducing relief valve is higher than the set pressure, the hydraulic oil flows back to the oil tank through the solenoid valve and the one-way valve to ensure that the oil pressure flowing into the leveling cylinder does not exceed the set value; when the crane stops moving forward, the hydraulic oil in the rod chamber of the leveling cylinder is damped by the throttle port of the second one-way throttle valve, so that the leveling cylinder cannot be extended or extends slowly, and at the same time, the hydraulic oil flows into the first one-way throttle valve through the pressure reducing relief valve and then flows through the solenoid valve. The magnetic reversing valves respectively enter the rodless chambers of the first leveling cylinder and the second leveling cylinder to prevent the rodless chambers of the leveling cylinders from being sucked empty; when the crane stops in reverse, the hydraulic oil in the rodless chambers of the leveling cylinders is damped by the throttle port of the first one-way throttle valve, so that the leveling cylinders cannot be retracted or retract slowly, so that the spreader remains in a horizontal state. At the same time, the hydraulic oil flows into the second one-way throttle valve through the pressure reducing relief valve and then flows through the electromagnetic reversing valve into the rod chambers of the first leveling cylinder and the second leveling cylinder to prevent the rod chambers of the leveling cylinders from being sucked empty.

[0036] Passive leveling of the sling: When a lifting machinery with a sling is in operation, due to the inertia and braking force of uneven road surfaces or when it stops, the sling's leveling cylinder extends or retracts due to inertia, resulting in a change in the angle between the sling and the boom. In order to keep the sling in a horizontal state at all times, the sling leveling hydraulic system provided in this embodiment is provided with a passive leveling function.

[0037] When a lifting machine with a sling is in operation, the hydraulic oil provided by the oil pump is reduced in pressure by the pressure-relief valve 30, flows through the one-way throttle valve, and then flows into the solenoid reversing valve 10. Simultaneously, it flows into the first and second leveling cylinders 81, 82. The rodless and rod-mounted cavities of the first and second leveling cylinders 81, 82 are connected, respectively. The oil circuit solenoid valve 20 and the one-way valve connected in parallel with the pressure-relief valve 30 also provide a pressure-limiting function. When the output pressure of the pressure-relief valve 30 exceeds the set pressure, the hydraulic oil flows back to the tank through the solenoid valve 20 and the one-way valve 70. This ensures that the oil pressure flowing into the leveling cylinders does not exceed the set value.

[0038] When the crane stops moving forward, inertia causes the first and second leveling cylinders 81 and 82 to extend. The oil in the rod chambers of these cylinders, damped by the throttle opening of the second one-way throttle valve 62, prevents them from extending or extends slowly, keeping the sling level. Simultaneously, hydraulic oil flows through the pressure-relief valve 30 into the first one-way throttle valve 61, then through the solenoid reversing valve 10 into the rodless chambers of the first and second leveling cylinders 81 and 82, respectively, preventing them from becoming emptied.

[0039] When the crane stops in reverse, inertia causes the first and second leveling cylinders 81 and 82 to retract. The hydraulic oil in the rodless chambers of the leveling cylinders, damped by the throttle opening of the first one-way throttle valve 61, prevents or slows the retraction of the cylinders, keeping the spreader horizontal. Simultaneously, the hydraulic oil flows through the pressure-relief valve into the second one-way throttle valve 62, then through the solenoid reversing valve 10 into the rod chambers of the first and second leveling cylinders 81 and 82, preventing the rod chambers from being emptied.

[0040] Step S200, the spreader active leveling step, when the boom is rapidly lifted, the angle detection device detects that the angle between the spreader and the boom is greater than a certain angle, the spreader's leveling cylinder quickly retracts, the electric proportional reversing valve, the electromagnetic reversing valve and the electromagnetic valve are energized, the oil pump outputs hydraulic oil from the electric proportional reversing valve into the two-way balancing valve through the control valve group A port into the rodless cavity of the leveling cylinder, the leveling cylinder quickly extends, and the two-way balancing valve is opened at the same time, and the hydraulic oil in the rod cavity of the leveling cylinder flows through the control valve group B port through the two-way The balancing valve enters the electric proportional reversing valve and flows back to the oil tank; when the boom descends rapidly, the angle detection device detects that the angle between the spreader and the boom is greater than a certain angle, the electric proportional reversing valve and the electromagnetic reversing valve are energized, and the hydraulic oil output by the oil pump flows from the electric proportional reversing valve into the two-way balancing valve through the B port of the control valve group and enters the rod chamber of the leveling cylinder. The leveling cylinder retracts and opens the two-way balancing valve at the same time. The hydraulic oil in the rodless chamber of the leveling cylinder flows through the A port of the control valve group through the two-way balancing valve, enters the electric proportional reversing valve and flows back to the oil tank.

[0041] Active leveling of the spreader: The spreader and boom are required to match different speeds to ensure the spreader remains horizontal during operation. An angle detection device is installed between the spreader and boom. When the boom is unloaded or lightly loaded, rapid raising and lowering is required to improve work efficiency. The spreader must be quickly leveled and aligned with the boom to maintain a horizontal position. When the boom is rapidly raised, the angle detection device detects that the angle between the spreader and boom exceeds a certain value. At this time, the electric proportional reversing valve 40, the solenoid reversing valve 10, and the solenoid valve 20 are energized. The hydraulic oil output by the oil pump flows from the left channel of the right position of the electric proportional reversing valve into the left check valve of the two-way balancing valve, through port A of the control valve group, and into the rodless chamber of the leveling cylinder. The leveling cylinder is rapidly extended, and at the same time, the oil in the other chamber opens the right side of the two-way balancing valve. The oil in the rod chamber of the leveling cylinder flows through port B of the control valve group, through the right side of the two-way balancing valve 50, and into the right channel of the right position of the electric proportional reversing valve 40, returning to the tank. When the boom descends rapidly, the angle detection device detects that the angle between the spreader and the boom is greater than a certain angle. At this time, the electric proportional reversing valve 40 and the electromagnetic reversing valve 10 are energized, and the oil pump outputs hydraulic oil from the pressure channel on the left side of the electric proportional reversing valve 40 into the one-way valve on the right side of the two-way balancing valve 50 through the B port of the control valve group and into the rod chamber of the leveling cylinder. The leveling cylinder retracts, and at the same time, another chamber of oil opens the left side of the two-way balancing valve 50. The hydraulic oil in the rodless chamber of the leveling cylinder flows through the A port of the control valve group through the left side of the two-way balancing valve 50 and enters the return oil channel on the left side of the electric proportional reversing valve 40 and flows back to the oil tank.

[0042] According to the different operating speeds and running trajectories of the boom, the proportional parameter value of the electric proportional reversing valve 40 is adjusted to match them, so as to achieve multi-stage or stepless speed regulation and leveling of the spreader, and the spreader adapts to the amplitude change of the boom.

[0043] Step S300, the bidirectional locking step of the leveling cylinder. When the angle between the spreader and the boom reaches the set value, the electric proportional reversing valve is de-energized and the electromagnetic reversing valve is energized, cutting off the hydraulic oil from entering the leveling cylinder, and the bidirectional balancing valve locks the rod chamber and the rodless chamber of the leveling cylinder.

[0044] When the angle between the spreader and the boom reaches a certain set value, the leveling cylinder needs to be bidirectionally locked to maintain a fixed position. The leveling cylinder supports the spreader and the load. At this point, the electric proportional reversing valve 40 is de-energized, while the solenoid reversing valve 10 is energized, cutting off the flow of hydraulic oil into the leveling cylinder. The bidirectional balancing valve 50 locks both chambers of the leveling cylinder.

[0045] Another aspect of the present invention also relates to a sling leveling hydraulic system control device, which is applied to the sling leveling hydraulic system as described above, and includes a sling passive leveling module, a sling active leveling module and a leveling cylinder two-way locking module, wherein the sling passive leveling module is used for the lifting machinery with the sling in the process of operation. When the output pressure of the pressure reducing relief valve is higher than the set pressure, the hydraulic oil flows back to the oil tank through the solenoid valve and the one-way valve to ensure that the oil pressure flowing into the leveling cylinder does not exceed the set value; when the crane stops moving forward, the hydraulic oil in the rod chamber of the leveling cylinder is damped by the throttle port of the second one-way throttle valve. When the crane is in reverse and stops, the hydraulic oil in the rodless cavity of the leveling cylinder is damped by the throttle port of the first one-way throttle valve, so that the leveling cylinder cannot be retracted or is retracted slowly, so that the spreader still maintains a horizontal state. At the same time, the hydraulic oil flows into the second one-way throttle valve through the pressure reducing relief valve and then flows through the electromagnetic reversing valve into the rod cavity of the first leveling cylinder and the second leveling cylinder to prevent the rod cavity of the leveling cylinder from being sucked empty. When the crane is in reverse and stops, the hydraulic oil in the rodless cavity of the leveling cylinder is damped by the throttle port of the first one-way throttle valve, so that the leveling cylinder cannot be retracted or is retracted slowly, so that the spreader still maintains a horizontal state. At the same time, the hydraulic oil flows into the second one-way throttle valve through the pressure reducing relief valve and then flows through the electromagnetic reversing valve into the rod cavity of the first leveling cylinder and the second leveling cylinder to prevent The sling active leveling module is used to prevent the rod chamber of the leveling cylinder from being sucked into the air; when the boom is lifted quickly, the angle detection device detects that the angle between the spreader and the boom is greater than a certain angle, the electric proportional reversing valve, the electromagnetic reversing valve and the electromagnetic valve are energized, and the oil pump outputs hydraulic oil from the electric proportional reversing valve into the two-way balancing valve through the A port of the control valve group and into the rodless chamber of the leveling cylinder. The leveling cylinder is quickly extended and the two-way balancing valve is opened at the same time. The hydraulic oil in the rod chamber of the leveling cylinder flows through the B port of the control valve group through the two-way balancing valve, enters the electric proportional reversing valve and flows back to the oil tank; when the boom is lowered quickly, the angle detection device detects that the angle between the spreader and the boom is greater than a certain angle, and the electric proportional reversing valve, the electromagnetic valve and the electromagnetic valve are energized, and the oil pump outputs hydraulic oil from the electric proportional reversing valve into the two-way balancing valve through the A port of the control valve group and into the rodless chamber of the leveling cylinder. When the angle is greater than a certain angle, the electric proportional reversing valve and the electromagnetic reversing valve are energized, and the hydraulic oil output by the oil pump flows from the electric proportional reversing valve into the two-way balancing valve through the B port of the control valve group and into the rod chamber of the leveling cylinder. The leveling cylinder retracts and opens the two-way balancing valve at the same time. The hydraulic oil in the rodless chamber of the leveling cylinder flows through the A port of the control valve group, through the two-way balancing valve, into the electric proportional reversing valve and flows back to the oil tank; the leveling cylinder two-way locking module is used to prevent the electric proportional reversing valve from being energized and the electromagnetic reversing valve from being energized when the angle between the spreader and the boom reaches the set value, cutting off the hydraulic oil from entering the leveling cylinder and locking the rod chamber and rodless chamber of the leveling cylinder with the two-way balancing valve.

[0046] Another aspect of the present invention relates to a crane, comprising the spreader leveling hydraulic system as described above, which will not be described in detail here.

[0047] The present embodiment provides a valve group, a sling leveling hydraulic system and its control method and device and a crane. Compared with the prior art, the valve group adopts an electromagnetic reversing valve, an electromagnetic valve, a pressure reducing relief valve, an electric proportional reversing valve, a two-way balancing valve, a first one-way throttle valve, a second one-way throttle valve, a one-way valve, a control valve group A port, a control valve group B port, a control valve group P port and a control valve group T port. The electromagnetic valve and the one-way valve are connected in series and then connected in parallel with the pressure reducing relief valve; the oil inlet P port of the electric proportional reversing valve is connected to the P port of the control valve group, and the oil return T port of the electric proportional reversing valve is connected to the T port of the control valve group; the electric proportional reversing valve The working A port is connected to the A port of the control valve group through a two-way balancing valve, and the working B port of the electric proportional reversing valve is connected to the B port of the control valve group through a two-way balancing valve; the oil outlet of the pressure reducing relief valve is connected to the T port of the control valve group, and the control oil port of the pressure reducing relief valve is connected to the P port of the control valve group; the oil inlet of the pressure reducing relief valve is divided into two paths, one path is connected to the P port of the electromagnetic reversing valve through the first one-way throttle valve; the other path is connected to the T port of the electromagnetic reversing valve after passing through the second one-way throttle valve; the A port of the electromagnetic reversing valve is connected to the A port of the control valve group, and the B port of the electromagnetic reversing valve is connected to the B port of the control valve group. The valve group, sling leveling hydraulic system, control method and device thereof, and crane provided in this embodiment are a sling leveling hydraulic system that adapts to the amplitude changes of the sling boom to achieve multi-stage or stepless leveling; it can passively level to meet the operating conditions, and actively level to adapt to the diversity of boom speed changes; it can achieve two-way locking of the leveling cylinder, and play a supporting role for the sling and the suspended object.

[0048] Although preferred embodiments of the present invention have been described, those skilled in the art may make additional changes and modifications to these embodiments once they are aware of the basic inventive concepts. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments and all changes and modifications that fall within the scope of the invention. Obviously, those skilled in the art may make various changes and modifications to the present invention without departing from the spirit and scope of the invention. Thus, the present invention is intended to include such changes and modifications as fall within the scope of the claims and their equivalents.

Claims

1. A hydraulic system for leveling a spreader, characterized in that: The invention comprises a valve group and a leveling oil cylinder connected to the valve group, wherein the valve group comprises an electromagnetic reversing valve (10), an electromagnetic valve (20), a pressure reducing relief valve (30), an electric proportional reversing valve (40), a two-way balancing valve (50), a first one-way throttle valve (61), a second one-way throttle valve (62), a one-way valve (70), a control valve group A port, a control valve group B port, a control valve group P port and a control valve group T port, wherein the electromagnetic valve (20) and the one-way valve (70) are connected in series and then connected in parallel with the pressure reducing relief valve (30); the oil inlet P port of the electric proportional reversing valve (40) is connected to the control valve group P port, and the oil return T port of the electric proportional reversing valve (40) is connected to the control valve group T port; the working A port of the electric proportional reversing valve (40) is connected to the two-way balancing valve (50) ) is connected to the A port of the control valve group, and the working B port of the electric proportional reversing valve (40) is connected to the B port of the control valve group through the two-way balancing valve (50); the oil outlet of the pressure reducing relief valve (30) is connected to the T port of the control valve group, and the control oil port of the pressure reducing relief valve (30) is connected to the P port of the control valve group; the oil inlet of the pressure reducing relief valve (30) is divided into two paths, one path is connected to the P port of the electromagnetic reversing valve (10) through the first one-way throttle valve (61); the other path is connected to the T port of the electromagnetic reversing valve (10) after passing through the second one-way throttle valve (62); the A port of the electromagnetic reversing valve (10) is connected to the A port of the control valve group, and the B port of the electromagnetic reversing valve (10) is connected to the B port of the control valve group; The spreader leveling hydraulic system also includes: The sling passive leveling module is used for lifting machinery with slings. During the operation, when the output pressure of the pressure reducing relief valve is higher than the set pressure, the hydraulic oil flows back to the oil tank through the solenoid valve and the one-way valve to ensure that the oil pressure flowing into the leveling cylinder does not exceed the set value; when the crane stops moving forward, the hydraulic oil in the rod chamber of the leveling cylinder is damped by the throttle port of the second one-way throttle valve, so that the leveling cylinder cannot be extended or extends slowly. At the same time, the hydraulic oil flows through the pressure reducing relief valve into the first one-way throttle valve and then flows through the solenoid reversing valve into the rodless chamber of the leveling cylinder to prevent the rodless chamber of the leveling cylinder from being sucked empty; when the crane stops reversing, the hydraulic oil in the rodless chamber of the leveling cylinder is damped by the throttle port of the first one-way throttle valve, so that the leveling cylinder cannot be retracted or retracts slowly, so that the sling remains in a horizontal state. At the same time, the hydraulic oil flows through the pressure reducing relief valve into the second one-way throttle valve and then flows through the solenoid reversing valve into the rod chamber of the leveling cylinder to prevent the rod chamber of the leveling cylinder from being sucked empty. The active leveling module of the spreader is used for: when the boom is rapidly raised, the angle detection device detects that the angle between the spreader and the boom is greater than a certain angle, the electric proportional reversing valve, the electromagnetic reversing valve and the solenoid valve are energized, and the hydraulic oil output by the oil pump flows from the electric proportional reversing valve into the two-way balancing valve through the A port of the control valve group and enters the rodless chamber of the leveling cylinder. The leveling cylinder is rapidly extended, and the two-way balancing valve is opened at the same time. The hydraulic oil in the rod chamber of the leveling cylinder flows through the B port of the control valve group, through the two-way balancing valve, into the electric proportional reversing valve and flows back to the oil tank; when the boom is rapidly lowered, the angle detection device detects that the angle between the spreader and the boom is greater than a certain angle, the electric proportional reversing valve and the electromagnetic reversing valve are energized, and the hydraulic oil output by the oil pump flows from the electric proportional reversing valve into the two-way balancing valve through the B port of the control valve group and enters the rod chamber of the leveling cylinder. The leveling cylinder is retracted, and the two-way balancing valve is opened at the same time. The hydraulic oil in the rodless chamber of the leveling cylinder flows through the A port of the control valve group, through the two-way balancing valve, into the electric proportional reversing valve and flows back to the oil tank; The two-way locking module of the leveling cylinder is used to cut off the hydraulic oil from entering the leveling cylinder when the angle between the spreader and the boom reaches the set value. The electric proportional reversing valve is de-energized and the electromagnetic reversing valve is energized, thereby locking the rod chamber and rodless chamber of the leveling cylinder with the two-way balancing valve.

2. The spreader leveling hydraulic system according to claim 1, characterized in that: The leveling oil cylinder comprises a first leveling oil cylinder (81) and a second leveling oil cylinder (82); the control valve group A port is connected to the rodless cavity of the first leveling oil cylinder (81) and the rodless cavity of the second leveling oil cylinder (82), respectively; the control valve group B port is connected to the rod cavity of the leveling oil cylinder.

3. The spreader leveling hydraulic system according to claim 2, characterized in that: The oil pump is connected to the oil tank through a delivery pipeline.

4. The spreader leveling hydraulic system according to claim 3, characterized in that: The sling leveling hydraulic system also includes an angle detection device and a controller. The angle detection device is arranged between the sling and the boom. The controller is electrically connected to the angle detection device, the electromagnetic reversing valve (10), the electromagnetic valve (20), and the electric proportional reversing valve (40) respectively. When the angle detection device detects that the angle between the sling and the boom reaches a set value, the controller controls the electromagnetic reversing valve (10), the electromagnetic valve (20), and the electric proportional reversing valve (40) to operate, and performs bidirectional locking on the leveling cylinder, so as to cause the leveling cylinder to maintain a certain posture and ensure that the sling of the crane is always in a horizontal state.

5. A method for controlling a spreader leveling hydraulic system, applied to the spreader leveling hydraulic system according to claim 4, characterized in that: The following steps are involved: The passive leveling step of the sling is that when the lifting machinery with the sling is in motion, when the output pressure of the pressure reducing relief valve is higher than the set pressure, the hydraulic oil flows back to the oil tank through the solenoid valve and the one-way valve to ensure that the oil pressure flowing into the leveling cylinder does not exceed the set value; when the crane stops moving forward, the hydraulic oil in the rod chamber of the leveling cylinder is damped by the throttle port of the second one-way throttle valve, so that the leveling cylinder cannot be extended or extends slowly, and at the same time, the hydraulic oil flows through the pressure reducing relief valve into the first one-way throttle valve and then flows through the electromagnetic reversing valve to respectively into the rodless chambers of the first and second leveling cylinders to prevent the rodless chambers of the leveling cylinders from being sucked empty; when the crane is reversed and stopped, the hydraulic oil in the rodless chambers of the leveling cylinders is damped by the throttle port of the first one-way throttle valve, so that the leveling cylinders cannot be retracted or are slowly retracted, so that the spreader remains in a horizontal state; at the same time, the hydraulic oil flows through the pressure reducing relief valve into the second one-way throttle valve and then flows through the electromagnetic reversing valve into the rod chambers of the first and second leveling cylinders to prevent the rod chambers of the leveling cylinders from being sucked empty; The active leveling step of the spreader is that when the boom is lifted quickly, the angle detection device detects that the angle between the spreader and the boom is greater than a certain angle, the electric proportional reversing valve, the electromagnetic reversing valve and the electromagnetic valve are energized, and the oil pump outputs hydraulic oil from the electric proportional reversing valve into the two-way balancing valve through the A port of the control valve group and into the rodless chamber of the leveling cylinder. The leveling cylinder is quickly extended and the two-way balancing valve is opened at the same time. The hydraulic oil in the rod chamber of the leveling cylinder flows through the B port of the control valve group through the two-way balancing valve and into the flow of the electric proportional reversing valve. Return to the oil tank; when the boom is rapidly lowered, the angle detection device detects that the angle between the spreader and the boom is greater than a certain angle, the electric proportional reversing valve and the electromagnetic reversing valve are energized, and the hydraulic oil output by the oil pump flows from the electric proportional reversing valve into the two-way balancing valve through the B port of the control valve group and into the rod chamber of the leveling cylinder. The leveling cylinder retracts and the two-way balancing valve is opened at the same time. The hydraulic oil in the rodless chamber of the leveling cylinder flows through the A port of the control valve group through the two-way balancing valve, enters the electric proportional reversing valve and flows back to the oil tank; The bidirectional locking step of the leveling cylinder is as follows: when the angle between the spreader and the boom reaches the set value, the electric proportional reversing valve is not energized and the electromagnetic reversing valve is energized, cutting off the hydraulic oil from entering the leveling cylinder, and the bidirectional balancing valve locks the rod chamber and the rodless chamber of the leveling cylinder.

6. A crane, characterized in that: It comprises the spreader leveling hydraulic system according to any one of claims 1 to 4.

Images