Quick emergency lowering control system for hydraulic crane

Abstract

The invention discloses a quick emergency lowering control system of hydraulic crane, which comprises a hand pump, a cylinder, a cylinder valve group, a lifting motor, a winch valve group and a hydraulic rotary motor. The hand pump is connected with a main valve through a control valve group. The main valve is internally provided with a cylinder working piece, a winch working piece and a rotary working piece. The cylinder working piece is connected with the cylinder through the cylinder valve group. The winch working piece is connected with the lifting motor through the winch valve group. The control valve group comprises a hand ball valve, a first hand directional valve and a second hand directional valve. The first hand directional valve is used for connecting the winch valve group. The second hand directional valve is used for connecting the cylinder valve group. According to the specification requirements of the crane, when the load is released in emergency, only the hand pump is needed to provide low control signal pressure oil, so that the crane boom and the lifted load can be safely and quickly released, and time and labor are saved.

Description

TECHNICAL FIELD

[0001] The present disclosure relates to a quick emergency lowering control system of a hydraulic crane. BACKGROUND

[0002] Most of the existing hydraulic crane structure is provided with a hoist winch and a variable amplitude of the jib. Among them, the hoist winch is driven by a hydraulic motor, and the jib is driven by a luffing cylinder. According to the corresponding crane specification requirements, the crane needs to have the ability to safely release the load in the case of power failure. For this type of crane, the jib and the load need to be safely lowered to a safe area by the emergency release control system in the case of power failure.

[0003] In the existing technology, as shown in Figures 6-7 The driving part in the hydraulic principle used is often relatively simple, basically using a manual pump as a power source to directly replace the oil pump motor set to drive the hydraulic actuator. In the emergency lowering process of the crane jib, the pressure oil from the manual pump flows to the left free passage of the cylinder valve group through the cylinder working piece of the main valve, enters the rod cavity of the luffing cylinder, and at the same time, the hydraulic oil in the rodless cavity of the luffing cylinder flows to the cylinder working piece of the main valve through the valve core of the balance valve, and finally returns to the oil tank through the oil return filter, so that the cylinder retracts and the jib lowers.

[0004] In the emergency lowering process of the hoist winch, most of the pressure oil from the manual pump flows to the A1 cavity of the hoist hydraulic motor through the winch working piece of the main valve; another small part of the pressure oil passes through the second hydraulic reversing valve of the shuttle valve in the winch valve group, passes through the one-way pressure reducing valve to make the winch brake loose, and the hydraulic oil in the B1 cavity of the hoist hydraulic motor flows to the winch working piece of the main valve through the valve core of the balance valve in the winch valve group, and finally returns to the oil tank through the oil return filter, so that the hoist winch lowers; when emergency rotation is needed, high-pressure oil discharged by the manual pump can directly drive the hydraulic rotary motor after passing through the rotary working piece of the main valve and the rotary motor valve group. As for the existing emergency release system of the hydraulic crane, due to the leakage of the hoist hydraulic motor, the most important thing is that the hoist hydraulic motor relies on the manual pump to provide hydraulic power when working, and the flow is very small, so the speed of the emergency release of the hoist winch is very slow. If the hoist winch needs to be lowered by a large height, a lot of time will be spent, and such an emergency release control system is time-consuming and laborious. In addition, for the emergency lowering of the jib, the manual pump also needs to actively provide hydraulic oil as the driving power, and the lowering time is also relatively long. SUMMARY

[0005] In order to solve the above problems, the present disclosure provides a quick emergency lowering control system of a hydraulic crane which can quickly respond and has more prominent ability to handle emergency scenes.

[0006] A rapid emergency lowering control system for a hydraulic crane includes a manual pump, a hydraulic cylinder, a hydraulic cylinder valve assembly, a hoisting motor, a winch valve assembly, and a hydraulic slewing motor. The manual pump is connected to a main valve via the control valve assembly. The main valve contains a hydraulic cylinder working plate, a winch working plate, and a slewing working plate. The hydraulic cylinder working plate is connected to the hydraulic cylinder via the hydraulic cylinder valve assembly, and the winch working plate is connected to the hoisting motor via the winch valve assembly.

[0007] The control valve group includes a manual ball valve, a first manual directional valve, and a second manual directional valve, wherein the first manual directional valve is used to connect to the winch valve group, and the second manual directional valve is used to connect to the cylinder valve group.

[0008] The hydraulic cylinder valve assembly includes a hydraulic cylinder valve assembly spool, a first hydraulic directional valve, a first speed control valve, a first replenishing valve, a back pressure valve, and a first hydraulically controlled check valve;

[0009] The winch valve assembly includes a first shuttle valve, a balance valve, a second hydraulic directional valve, a one-way pressure reducing valve, a third hydraulic directional valve, a second speed regulating valve, a second hydraulically controlled one-way valve, a second oil replenishing valve, and a second shuttle valve.

[0010] The emergency release of the crane boom includes the following steps:

[0011] The high-pressure oil from the manual pump connects the inlet and outlet of the first hydraulic directional valve. The high-pressure oil in the rodless chamber of the cylinder is divided into two low-pressure oil paths by the back pressure valve after passing through the first hydraulic directional valve and the first speed control valve. One low-pressure oil path flows back to the rod chamber of the cylinder to replenish the oil in the rod chamber. The other path of excess hydraulic oil flows back to the oil tank after passing through the back pressure valve. The boom is safely lowered at a predetermined speed. At this time, the first hydraulic check valve closes the main oil circuit of the cylinder.

[0012] Furthermore, in order to change the working radius of the hydraulic crane, the boom is driven by a luffing cylinder.

[0013] In order to change the slewing angle of the crane, the hydraulic slewing motor is connected to the main valve through the slewing motor valve group, and the slewing working plate is connected to the hydraulic slewing motor through the slewing motor valve group.

[0014] The emergency release of the load lifted by the hoisting winch includes the following steps:

[0015] The high-pressure oil from the manual pump is divided into two paths: one path connects the inlet and outlet of the third hydraulic directional valve, and the high-pressure oil from port B1 of the hydraulic motor returns to port A1 on the low-pressure side of the hydraulic motor after passing through the third hydraulic directional valve and the second speed control valve; at the same time, a branch of this high-pressure oil flows through the second shuttle valve, through the third hydraulic directional valve and the one-way pressure reducing valve, and finally opens the winch brake, and the hoisting winch begins to lower the load. At this time, the other path of high-pressure oil from the first manual valve replenishes the low-pressure side of the hydraulic motor through the second replenishing valve.

[0016] To protect the actuators, an overflow valve is installed in the main valve, which is connected in parallel with the cylinder working plate, winch working plate, and slewing working plate.

[0017] Furthermore, the back pressure valve in the cylinder valve group is connected to the first speed control valve, the first speed control valve is connected in sequence to the first hydraulic directional valve and the cylinder valve group valve core, and the first oil replenishment valve is connected to the first speed control valve.

[0018] Furthermore, the main valve is connected to the oil tank via a return oil filter.

[0019] Furthermore, the manual ball valve is connected to the main valve, and flows through the rotary working plate to the rotary motor valve assembly, which is connected to the hydraulic rotary motor.

[0020] Furthermore, the working oil port of the manual ball valve is directly connected to the first manual valve, the second manual valve, the manual pump, and the main valve, respectively.

[0021] Beneficial effects:

[0022] In emergency situations, especially when a crane experiences a power system failure during operation, it is crucial to safely lower the boom and load to a safe area. This emergency lowering control system for hydraulic cranes optimizes previous hydraulic system designs by supplying only a minimal amount of hydraulic oil needed to control the system via a manual pump, while simultaneously replenishing the small amount lost due to internal leaks. This method cleverly utilizes the gravitational potential energy of the load itself, significantly improving the efficiency of emergency load lowering and achieving time- and labor-saving emergency operations. Attached Figure Description

[0023] Figure 1 This is the overall control diagram of a rapid emergency lowering control system for a hydraulic crane;

[0024] Figure 2 This is a magnified view of a portion of the winch valve assembly and hydraulic motor section;

[0025] Figure 3 This is a magnified view of a portion of the rotating section;

[0026] Figure 4 This is a magnified view of a portion of the main valve section;

[0027] Figure 5 This is a magnified view of a portion of the balance valve and the variable amplitude cylinder.

[0028] Figure 6 This is a schematic diagram of a hydraulic cylinder valve assembly without functions such as reversing and speed regulation in the prior art;

[0029] Figure 7 This is a schematic diagram of a winch valve assembly without functions such as reversing in the existing technology;

[0030] in:

[0031] 1. Manual pump;

[0032] 2. Main valve;

[0033] 3. Hydraulic cylinder valve assembly;

[0034] 4. Luffing cylinder;

[0035] 5. Winch valve assembly;

[0036] 6. Lifting motor;

[0037] 7. Return oil filter;

[0038] 8. Hydraulic rotary motor;

[0039] 9. Rotary motor valve assembly;

[0040] 10. Manual ball valve;

[0041] 11. First manual directional valve;

[0042] 12. Second manual directional valve;

[0043] 2-1. Relief valve;

[0044] 2-2. Hydraulic cylinder working plate;

[0045] 2-3. Winch working discs;

[0046] 2-4. Rotary working plate;

[0047] 3-1. Valve core of hydraulic cylinder valve assembly;

[0048] 3-2, First hydraulic directional valve;

[0049] 3-3, First speed control valve;

[0050] 3-4. First oil replenishment valve;

[0051] 3-5. Back pressure valve;

[0052] 3-6. First hydraulically controlled check valve;

[0053] 5-1, First shuttle valve;

[0054] 5-2. Balancing valve;

[0055] 5-3. Second hydraulic directional valve;

[0056] 5-4. One-way pressure reducing valve;

[0057] 5-5. Third hydraulic directional valve;

[0058] 5-6. Second speed control valve;

[0059] 5-7. Second hydraulically controlled check valve;

[0060] 5-8. Second oil replenishment valve;

[0061] 5-9, Second shuttle valve. Detailed Implementation

[0062] To enhance understanding of the present invention, the invention will be further described in detail below with reference to embodiments and accompanying drawings. These embodiments are only for explaining the invention and do not constitute a limitation on the scope of protection of the invention.

[0063] Example 1:

[0064] like Figures 1-5 As shown, a rapid emergency lowering control system for a hydraulic crane includes a manual pump 1, a main valve 2, a cylinder valve assembly 3, a luffing cylinder 4, a winch valve assembly 5, a hoisting motor 6, a return oil filter 7, a hydraulic rotary motor 8, a rotary motor valve assembly 9, a manual ball valve 10, a first manual directional valve 11, and a second manual directional valve 12. The specific connection and configuration structure is as follows... Figure 1 As shown.

[0065] The cylinder valve group 3 includes a balance valve 3-1, a first hydraulic directional valve 3-2, a first speed regulating valve 3-3, a first replenishing valve 3-4, a back pressure valve 3-5, and a first hydraulically controlled check valve 3-6.

[0066] The winch valve assembly 5 includes a first shuttle valve 5-1, a balance valve 5-2, a second hydraulic directional valve 5-3, a one-way pressure reducing valve 5-4, a third hydraulic directional valve 5-5, a second speed regulating valve 5-6, a second hydraulically controlled one-way valve 5-7, a second oil replenishing valve 5-8, and a second shuttle valve 5-9.

[0067] The system is equipped with a manual ball valve 10, which allows the system to function exactly the same as before the improvement in the initial state. It retains the high-pressure oil that can be discharged by the manual pump 1, which flows through the rotary working plate 2-4 of the main valve 2 and then through the rotary motor valve group 9 to directly drive the hydraulic rotary motor 8, thereby realizing the manual emergency rotary function.

[0068] When an emergency release of the boom is required, turn the handle of the manual ball valve 10 to allow the pressurized oil from the manual pump 1 to flow through the second manual valve 12, and manually switch the second manual valve 12.

[0069] At this time, the high-pressure oil from manual pump 1 connects the inlet and outlet of the first hydraulically controlled directional valve 3-2. The high-pressure oil in the rodless chamber of the luffing cylinder 4 is divided into two low-pressure oils of approximately 0.5 MPa each by the first hydraulically controlled directional valve 3-2 and the first speed control valve 3-3, under the action of the back pressure valve 3-5. One low-pressure oil flows back to the rod chamber of the luffing cylinder 4 to replenish the rod chamber, while the excess hydraulic oil flows back to the oil tank through the back pressure valve 3-5. The boom is then safely lowered at the predetermined speed. In the cylinder valve group, the first hydraulically controlled check valve 3-6 mainly functions to close the main oil circuit of the luffing cylinder.

[0070] When it is necessary to release the load lifted on the hoisting winch in an emergency, turn the handle of the manual ball valve 10 to make the pressure oil from the manual pump 1 flow through the first manual valve 11 and manually switch the first manual valve 11. At this time, the high pressure oil from the manual pump 1 is divided into two paths: one path of high pressure oil connects the inlet and outlet of the third hydraulic control directional valve 5-5, and the high pressure oil from port B1 of the hydraulic motor 6 returns to port A1 of the low pressure side of the hydraulic motor 6 after passing through the third hydraulic control directional valve 5-5 and the second speed control valve 5-6; at the same time, a branch of this high pressure oil flows through the second shuttle valve 5-9, then through the second hydraulic directional valve 5-3 and the one-way pressure reducing valve 5-4, and finally opens the winch brake, and the hoisting winch begins to lower the load.

[0071] In addition, another line of high-pressure oil from the first manual valve 11 replenishes the low-pressure side of the hydraulic motor 6 via the replenishing valve 5-8 to compensate for the hydraulic oil lost by the hydraulic motor due to leakage. This prevents the hydraulic motor from being damaged by a vacuum during high-speed load lowering.

[0072] In the hydraulic cylinder luffing cylinder valve group 3, a first speed regulating valve 3-3 is installed. By adjusting the opening size of the throttle orifice in the first speed regulating valve 3-3, the emergency lowering speed of the lifting boom can be changed. In the lifting winch valve group 5, a second speed regulating valve 5-6 is installed. By adjusting the opening size of the throttle orifice in the second speed regulating valve 5-6, the lowering speed of the load lifted by the lifting winch during emergency lowering can be changed. In the lifting winch valve group 5, a replenishing oil valve 5-8 is installed to replenish the hydraulic oil lost by leakage of the hydraulic motor itself, preventing the hydraulic motor from being sucked into cavitation and damaged during the high-speed lowering process of the lifting winch relying on gravity.

[0073] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A quick emergency lowering control system of a hydraulic crane, comprising a hand pump, a cylinder, a cylinder valve group, a hoisting motor, a winch valve group and a hydraulic rotary motor, the hand pump being connected to a main valve through a control valve group, the main valve being internally provided with a cylinder working piece, a winch working piece and a rotary working piece, wherein the cylinder working piece is connected to the cylinder through the cylinder valve group, and the winch working piece is connected to the hoisting motor through the winch valve group; characterized in that the control valve group comprises a hand ball valve, a first hand directional valve and a second hand directional valve, wherein the first hand directional valve is used to connect the winch valve group, and the second hand directional valve is used to connect the cylinder valve group; the cylinder valve group comprises a cylinder valve group spool, a first hydraulic directional valve, a first speed regulating valve, a first oil supplement valve, a back pressure valve and a first hydraulic control check valve; the winch valve group comprises a first shuttle valve, a balance valve, a second hydraulic directional valve, a one-way pressure reducing valve, a third hydraulic directional valve, a second speed regulating valve, a second hydraulic control check valve, a second oil supplement valve and a second shuttle valve; the emergency release of the crane boom comprises the following steps: high-pressure oil of the hand pump is connected to the first hydraulic control directional valve, high-pressure oil in the rodless cavity of the cylinder is divided into two low-pressure oils through the first hydraulic control directional valve and the first speed regulating valve under the action of the back pressure valve, one of the low-pressure oils flows back to the rod cavity of the cylinder to supplement the rod cavity of the cylinder, and the other low-pressure oil flows back to the oil tank through the back pressure valve, the crane boom is safely lowered at a predetermined speed, and the first hydraulic control check valve closes the main oil circuit of the cylinder; the emergency release of the load on the crane winch comprises the following steps: high-pressure oil of the hand pump is divided into two paths, one of the high-pressure oils connects the third hydraulic control directional valve, and high-pressure oil at B1 port of the hydraulic motor flows back to A1 port of the low-pressure side of the hydraulic motor through the third hydraulic control directional valve and the second speed regulating valve; at the same time, a branch of the high-pressure oil flows through the second shuttle valve, the third hydraulic directional valve and the one-way pressure reducing valve, finally opens the winch brake, and the crane winch starts to lower the load, and the other high-pressure oil out of the first hand valve supplements the low-pressure side of the hydraulic motor through the second oil supplement valve. The crane boom is driven by a luffing cylinder. The hydraulic rotary motor is connected to the main valve through a rotary motor valve group, and the rotary working piece is connected to the hydraulic rotary motor through the rotary motor valve group. The main valve is provided with an overflow valve, and the overflow valve is connected in parallel with the cylinder working piece, the winch working piece and the rotary working piece. The back pressure valve in the cylinder valve group is connected to the first speed regulating valve, the first speed regulating valve is connected to the first hydraulic directional valve and the cylinder valve group spool in sequence, and the first oil supplement valve is connected to the first speed regulating valve. The main valve is connected to the oil tank through an oil return filter. The hand ball valve is connected to the main valve, flows through the rotary motor valve group through the rotary working piece, and is connected to the hydraulic rotary motor. The control system is provided with the hand ball valve, and working oil ports of the hand ball valve are directly connected to the first hand valve, the second hand valve, the hand pump and the main valve respectively.

2. A quick emergency lowering control system for a hydraulic crane according to claim 1, characterized in that, ​ 3. A quick emergency lowering control system of a hydraulic crane according to claim 1 or 2, characterized in that, ​ 4. A quick emergency lowering control system for a hydraulic crane according to claim 3, characterized in that ​ 5. A quick emergency lowering control system for a hydraulic crane as defined in claim 1, characterized in that ​ 6. A quick emergency lowering control system for a hydraulic crane according to claim 1, characterized in that, ​ 7. A quick emergency lowering control system for a hydraulic crane as defined in claim 1, characterized in that ​ 8. A quick emergency lowering control system for a hydraulic crane according to claim 6, characterized in that, ​

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