CN115402956A

CN115402956A - Winch balance valve, winch hydraulic system and hoisting engineering machinery

Info

Publication number: CN115402956A
Application number: CN202110592900.XA
Authority: CN
Inventors: 夏丹枫; 涂绪荣; 唐迁
Original assignee: Changde Zhonglian Zhongke Hydraulic Co ltd; Zoomlion Heavy Industry Science and Technology Co Ltd
Current assignee: Changde Zhonglian Zhongke Hydraulic Co ltd; Zoomlion Heavy Industry Science and Technology Co Ltd
Priority date: 2021-05-28
Filing date: 2021-05-28
Publication date: 2022-11-29

Abstract

The invention relates to a hydraulic balance valve, and discloses a winch balance valve, a winch hydraulic system and a hoisting engineering machine, wherein the winch balance valve comprises a balance valve core, a winch brake valve for controlling a winch brake, a first oil port and a second oil port, the balance valve core is arranged on an oil path between the first oil port and the second oil port of the winch balance valve, the winch brake valve comprises an oil inlet for being connected with a system low-pressure control oil path, a pressure maintaining oil path is arranged between the oil inlet of the winch brake valve and the second oil port of the winch balance valve, and a one-way valve is arranged on the pressure maintaining oil path so that hydraulic oil can be unidirectionally output to the second oil port of the winch balance valve from the oil inlet of the winch brake valve. The invention can reduce abnormal sound and pressure fluctuation caused by collision between wheel teeth in the process of the winch motor from rest to work.

Description

Winch balance valve, winch hydraulic system and hoisting engineering machinery

Technical Field

The invention relates to a hydraulic balance valve, in particular to a winch balance valve. In addition, still relate to a hoist hydraulic system and jack-up engineering machine tool.

Background

Hoisting engineering machinery such as automobile cranes and crawler cranes usually adopt a driving mode of matching a hydraulic motor and a speed reducer to control hoisting actions, when the hoisting engineering machinery works, a hydraulic system drives the hydraulic motor to rotate, the hydraulic motor drives a hoisting speed reducer to rotate, and finally, a steel wire rope directly drives a heavy object or drives the heavy object through a pulley block, so that the heavy object can be lifted and lowered. Because the hoisting working conditions have different requirements on speed and load, the hoisting mechanism is relatively frequently started and braked, the working condition is poor, and the hoisting mechanism is required to be stably, reliably and impact-free when being started, braked and stably operated based on the consideration of the operation performance; based on the consideration of safety performance, the hoisting mechanism is required to be capable of keeping a load for a long time, and accidents such as heavy object falling cannot occur when the heavy object is empty, so that the requirements on the leakage of a balance valve of the hoisting system and the flexibility of parts such as a valve core are extremely high.

In the hoisting system, a hoisting brake and a balance valve are also arranged to keep the safety of the hoisting system. Specifically, referring to fig. 1, a first working port A1 of a main valve is connected to a first port A2 of a hoist motor 9 through a balance valve 10, the first working port A1 of the main valve is connected to a pressure reducing valve 11 through a shuttle valve, the pressure reducing valve 11 is connected to a control port K1 of a hoist brake, a second working port B1 of the main valve is connected to a second port B2 of the hoist motor 9, and meanwhile, the second working port B1 of the main valve is connected to the pressure reducing valve 11 through the shuttle valve. When a heavy object is lifted, one part of hydraulic oil output by the first working oil port A1 of the main valve reaches the first oil port A2 of the hoisting motor 9 through the balance valve 10 to drive the hoisting motor, meanwhile, the other part of hydraulic oil output by the first working oil port A1 of the main valve is output to the control port K1 of the hoisting brake through the shuttle valve and the pressure reducing valve 11 to open the hoisting brake, and hoisting and lifting actions are realized; when the heavy object is placed, one part of the hydraulic oil output by the second working oil port B1 of the main valve is output to the second oil port B2 of the winch motor 9 to drive the winch motor, and meanwhile, the other part of the hydraulic oil output by the second working oil port B1 of the main valve is output to the control port K1 of the winch brake through the shuttle valve and the pressure reducing valve 11 to open the winch brake, so that the winch placing action is realized.

However, because the hoisting motor 9 has uncontrollable internal leakage, a part of the oil leaks to the system zero-pressure leakage oil path from the high-pressure chamber of the hoisting motor 9, and the oil pressure between the second oil port B of the hoisting balance valve and the first oil port A2 of the hoisting motor 9 is reduced along with the internal leakage of the hoisting motor 9. Meanwhile, a gap inevitably exists due to the matching between the motor spline and the winch speed reducer gear, so that the transmission part and the driven part float. When the oil pressure between the second oil port B of the hoisting balance valve and the first oil port A2 of the hoisting motor 9 is reduced, a gap occurs between the teeth of the gear which are originally tightly matched. When the winch system is started again after stopping working, the clearance between the gear teeth can disappear rapidly under the action of pressure oil, so that the gear teeth collide rapidly with each other, and abnormal sound and pressure fluctuation are generated.

Disclosure of Invention

The technical problem to be solved by the first aspect of the present invention is to provide a hoisting balance valve, which can reduce abnormal noise caused by collision between wheel teeth and pressure fluctuation generated thereby when a hoisting motor is in operation from rest.

In order to solve the technical problems, a first aspect of the invention provides a winch balance valve, which comprises a balance valve core, a winch brake valve used for controlling a winch brake, a first oil port and a second oil port, wherein the balance valve core is arranged on an oil path between the first oil port and the second oil port of the winch balance valve, the winch brake valve comprises an oil inlet used for being connected with a system low-pressure control oil path, a pressure maintaining oil path is arranged between the oil inlet of the winch brake valve and the second oil port of the winch balance valve, and a check valve is arranged on the pressure maintaining oil path so that hydraulic oil can be output to the second oil port of the winch balance valve from the oil inlet of the winch brake valve in a one-way mode.

Optionally, a damper is further disposed on the pressure-maintaining oil path.

The shuttle valve comprises a first oil inlet connected with the first oil port of the winch balance valve, a second oil inlet connected with the third oil port of the winch balance valve and an oil outlet connected with the control port of the winch brake valve.

Optionally, the third oil port of the hoisting balance valve is connected with the pilot control port of the balance valve core.

Optionally, a filter is disposed on a pilot oil path between the third oil port of the hoisting balance valve and the pilot control port of the balance valve core.

Optionally, the winch brake valve comprises an oil outlet for connection with a control port of the winch brake.

The technical problem to be solved by the second aspect of the present invention is to provide a hoisting hydraulic system, which can reduce abnormal noise caused by collision between wheel teeth and pressure fluctuation generated thereby in the process of the hoisting motor from rest to work.

In order to solve the technical problem, a second aspect of the present invention provides a hoisting hydraulic system, including a hoisting motor, a main valve, and the hoisting balance valve in any one of the above technical solutions, wherein a first working oil port of the main valve is connected to a first oil port of the hoisting balance valve, a second working oil port of the main valve is respectively connected to a third oil port of the hoisting balance valve and a second oil port of the hoisting motor, and the first oil port of the hoisting motor is connected to the second oil port of the hoisting balance valve.

Optionally, an oil drainage port is arranged on the hoisting motor.

Optionally, an oil drain port of the hoisting motor is connected with the oil leakage path.

The technical problem to be solved by the third aspect of the present invention is to provide a hoisting engineering machine, which has better stability of the hoisting system.

In order to solve the technical problem, a third aspect of the present invention provides a hoisting engineering machine, including the hoisting hydraulic system according to any one of the above technical solutions.

Through the technical scheme, the invention has the following beneficial effects:

according to the invention, a pressure maintaining oil path is arranged between an oil inlet of the winch brake valve and a second oil port of the winch balance valve, the pressure maintaining oil path and a system low-pressure control oil path are arranged, and oil output by the system low-pressure control oil path can be output to the second oil port of the winch balance valve through the pressure maintaining oil path; after the winch balance valve is applied to a specific winch hydraulic oil circuit, the second oil port of the winch balance valve is connected with the oil inlet at one end of the winch motor, so that splines and gears at various positions in the winch motor and the winch speed reducer can be tightly attached; therefore, in the process that the hoisting motor is lifted from a static state to a hoisting state, the clearance between the teeth of the clearance gear can be eliminated in advance, the collision generated when the spline and the gear are in a floating state to a close fit state and the abnormal sound generated by the collision are reduced or even avoided, the stability of a hoisting hydraulic system is improved, and the service life of a hoisting speed reducer is prolonged.

Additional features and advantages of the invention will be set forth in the detailed description which follows.

Drawings

The accompanying drawings, which are included to provide a further understanding of the invention and are incorporated in and constitute a part of this specification, illustrate embodiments of the invention and together with the description serve to explain the principles of the invention and not to limit the invention. In the drawings:

FIG. 1 is a hydraulic schematic of a prior art hoist hydraulic system;

FIG. 2 is a hydraulic schematic diagram of a hoist hydraulic system according to an embodiment of the present invention;

FIG. 3 is a schematic diagram of the interaction of a hoist motor and a hoist reducer according to an embodiment of the present invention;

fig. 4 is a second schematic structural diagram illustrating interaction between a hoist motor and a hoist reducer according to the second embodiment of the present invention.

Description of the reference numerals

1 balance valve core 2 hoisting brake

Control port 3 hoisting brake valve of K1 hoisting brake

Oil return port of oil inlet T winch brake valve of P winch brake valve

Control port of oil outlet Z winch brake valve of K winch brake valve

4 system low pressure control oil circuit 5 one-way valve

6 damping 7 shuttle valve

a first oil inlet of the shuttle valve and b second oil inlet of the shuttle valve

Oil outlet 8 filter of c shuttle valve

First oil port of winch balance valve A and second oil port of winch balance valve B

Third oil port 9 hoisting motor of X hoisting balance valve

First oil port of A2 hoisting motor and second oil port of B2 hoisting motor

Oil drain 100 leakage oil path of T1 hoisting motor

First working oil port of A1 main valve and second working oil port of B1 main valve

10 balance valve 11 pressure reducing valve

10a hoist motor key shaft 11a hoist reducer

12a load weight

Detailed Description

The following detailed description of embodiments of the invention refers to the accompanying drawings. It should be understood that the detailed description and specific examples, while indicating the present invention, are given by way of illustration and explanation only, not limitation.

In the description of the present invention, it should be noted that, unless otherwise explicitly stated or limited, the terms "mounted," "disposed" or "connected" are to be construed broadly, e.g., the term "connected" may be a fixed connection, a detachable connection, or an integral connection; they may be connected directly or indirectly through intervening media, or they may be connected through inter-element communication or interaction between two elements. The specific meanings of the above terms in the present invention can be understood by those skilled in the art according to specific situations.

Furthermore, the terms "first", "second", "third" are used for descriptive purposes only and are not to be construed as indicating or implying a relative importance or implicitly indicating the number of technical features indicated, and therefore the features defined "first", "second", "third" may explicitly or implicitly include one or more of the features described.

First, it should be noted that the hoist balance valve of the present invention belongs to the hydraulic field, and the substantial technical concept of the hoist balance valve is the hydraulic connection relationship for those skilled in the art. The related hydraulic components, such as pressure reducing valves, reversing valves, hydraulic motors, check valves, etc., are well known to those skilled in the art and are common components in existing hydraulic systems, and therefore, they will be described only briefly below. After knowing the technical idea of the present invention, those skilled in the art can also simply replace the oil path or the valve, etc. to implement the function of the hoisting balance valve of the present invention, which also belongs to the protection scope of the present invention.

In the present invention, the directional terms used are based on the orientation or positional relationship shown in the drawings, and do not indicate or imply that the referenced device or element must have a particular orientation, be constructed and operated in a particular orientation, and thus should not be construed as limiting the present invention; the directional terminology of the present invention should be understood in conjunction with the actual installation state.

As shown in fig. 2, the winch balance valve according to the basic embodiment of the present invention includes a balance valve core 1, a winch brake valve 3 for controlling the winch brake 2, a first oil port a, and a second oil port B, wherein the balance valve core 1 is disposed on an oil path between the first oil port a and the second oil port B of the winch balance valve, the winch brake valve 3 includes an oil inlet P for connecting with a system low-pressure control oil path 4, a pressure maintaining oil path is disposed between the oil inlet P of the winch brake valve 3 and the second oil port B of the winch balance valve, and a check valve 5 is disposed on the pressure maintaining oil path to enable hydraulic oil to be unidirectionally output from the oil inlet P of the winch brake valve 3 to the second oil port B of the winch balance valve.

In order to facilitate understanding of the technical scheme of the hoisting balance valve of the present invention, the hoisting balance valve of the present invention is combined into a specific hoisting hydraulic system, and the first oil port A2 of the hoisting motor 9 is taken as a lifting oil port and the second oil port B2 of the hoisting motor 9 is taken as a lower oil port for example.

Although, in the following embodiments, the first port A2 of the hoist motor 9 is used for lifting and the second port B2 of the hoist motor 9 is used for lowering, it is understood that the first port A2 of the hoist motor 9 may be used for lowering and the second port B2 of the hoist motor 9 may be used for lifting.

The problem that in the prior art, gear teeth rapidly collide with each other to generate abnormal sound and pressure fluctuation when a hoisting hydraulic system is restarted after stopping working due to uncontrollable internal leakage of a hoisting motor 9 is solved; the winch balance valve is designed in a targeted manner, namely a pressure maintaining oil way is arranged between an oil inlet P of the winch brake valve 3 and a second oil port B of the winch balance valve, and a check valve 5 is arranged on the pressure maintaining oil way, so that oil can only flow from the oil inlet P of the winch brake valve 3 to the second oil port B of the winch balance valve in a one-way manner; after the winch balance valve is installed in the winch hydraulic system, referring to fig. 2, the oil inlet P of the winch brake valve 3 is connected with the system low-pressure control oil path 4, and the second oil port B of the winch balance valve is connected with the first oil port A2 of the winch motor 9. Thus, although the hoisting motor 9 has uncontrollable internal leakage, and a part of oil leaks to the system zero-pressure leakage oil path 100 from the high-pressure cavity of the hoisting motor 9 through the oil drain port T1, the invention can continuously supplement the oil to the hoisting motor 9 through the system low-pressure control oil path 4, so that the hoisting motor 9 always has a part of back pressure, eliminates the gap between the spline and the gear, avoids the collision generated when the spline and the gear are in a close fit state from a floating state, or plays a role in buffering the change of the gap position of the connection part of the spline and the gear, and lightens the collision generated when the spline and the gear are in a close fit state from a floating state; therefore, collision and pressure fluctuation generated when the floating state of the connecting part is converted into the tight fit state due to internal leakage of the motor are effectively reduced, the stability of the winch hydraulic system can be greatly improved, and the service life of the winch speed reducer is prolonged.

In addition, as a specific embodiment, a hydraulic pilot mode can be selected to control the hoisting brake valve 3, and in an optimal case, the hoisting brake valve 3 can be a two-position three-way reversing valve; referring to fig. 2, a third oil port X is formed in the hoisting balance valve, a shuttle valve 7 is disposed in the hoisting balance valve, a first oil inlet a of the shuttle valve 7 is connected with a first oil port a of the hoisting balance valve, a second oil inlet b of the shuttle valve 7 is connected with the third oil port X of the hoisting balance valve, and an oil outlet c of the shuttle valve 7 is connected with a control port Z of the hoisting brake valve 3; a second oil port B2 of the winch motor 9 is connected with a second working oil port B1 of the main valve, a third oil port X of the winch balance valve is also connected with the second working oil port B1 of the main valve, a first oil port A2 of the winch motor 9 is connected with a second oil port B of the winch balance valve, a first oil port A of the winch balance valve is also connected with a first working oil port A1 of the main valve, and an oil outlet K of the winch brake valve 3 is connected with a control port K1 of the winch brake 2; due to the fact that the shuttle valve 7 is arranged, oil pressure between the first oil inlet a and the second oil inlet b of the shuttle valve 7 can be compared, oil is output to the control port Z of the winch brake valve 3 through the oil outlet c of the shuttle valve 7, the spool of the winch brake valve 3 is driven to change direction, the winch brake 2 is opened, the winch motor 9 is made to rotate, and a heavy object is driven to ascend or descend. Of course, the hoisting brake valve 3 may also be controlled in an electrically controlled manner, for example, the hoisting brake valve 3 may be a two-position three-way electromagnetic directional valve.

In a specific operation process, when the main winch control handle is operated to move towards the ascending direction of the winch, most of hydraulic oil output from the first working oil port A1 of the main valve flows to the first oil port A2 of the winch motor 9 in a single direction through the balance valve core 1, meanwhile, a small part of hydraulic oil flows to the first oil inlet a of the shuttle valve 7, the pressure between the first oil inlet a and the second oil inlet b of the shuttle valve 7 is compared, the oil with higher pressure is output to the control port Z of the winch brake valve 3 through the oil outlet c of the shuttle valve 7 after comparison, the valve core of the winch brake valve 3 is driven to change direction, the system low-pressure control oil circuit 4 supplies low-pressure control oil to the winch brake 2, the winch brake 2 is opened, the winch motor 9 can rotate, and the heavy object is driven to ascend; when the main winch control handle is operated to move towards the downward moving direction of the winch, hydraulic oil is output from the second working oil port B1 of the main valve, most of the hydraulic oil is output towards the second oil port B2 of the winch motor 9, a small part of the hydraulic oil flows towards the third oil port X, the hydraulic oil is divided into two parts, one part of the hydraulic oil flows towards the pilot control port of the balance valve core 1, the valve core of the balance valve core 1 is driven to change direction, the hydraulic oil output from the first oil port A2 of the winch motor 9 can flow back to the oil tank through the balance valve core 1, a throttling hole is formed in the channel of the balance valve core 1, the hydraulic oil can flow back slowly, the stability of the downward moving action is guaranteed, the other part of the hydraulic oil flows towards the second oil inlet B of the shuttle valve 7, the pressure between the first oil inlet a and the second oil inlet B of the shuttle valve 7 is compared, the hydraulic oil with the higher pressure after comparison is output towards the control port Z of the winch valve 3 through the oil outlet c of the shuttle valve 7, the valve 3 is driven to change direction, the valve core of the system low-pressure control oil circuit 4 is used for providing low-pressure control oil to the winch brake 2, the winch brake 2 is opened, and the downward moving motor 9 can drive heavy objects. In the above manner that the system low-pressure control oil path 4 supplies low-pressure control oil to the winch brake 2 through the winch brake valve 3, both the winch brake 2 and the winch brake valve 3 may use springs with lower rigidity, so that both the winch brake valve 3 and the winch brake 2 have lower opening pressure, wherein low pressure means that the oil pressure is 1-2Mpa, and only 1-2Mpa is needed to open the winch brake 2 and provide certain pre-pressure for the winch motor 9; the pressure difference between the first oil inlet a and the second oil inlet B of the shuttle valve 7 is substantially related to the pressure difference between the first working oil port A1 and the second working oil port B1 of the main valve, that is, when the main winch operating handle is operated in the winch ascending direction or the main winch operating handle is operated in the winch descending direction, the pressure difference exists between the first working oil port A1 and the second working oil port B1 of the main valve, so that the control oil can be output to the control port Z of the winch brake valve 3 through the oil outlet c of the shuttle valve 7. When load pressure is lower, namely when the first working oil port A1 and the second working oil port B1 of the main valve are very low in pressure, the control port Z of the winch brake valve 3 can be acted on, so that low-pressure control oil is output to the control port K1 of the winch brake valve 2 through the oil outlet K of the winch brake valve 3, the winch brake 2 is opened, the winch motor 9 is rotated, the whole winch hydraulic system can normally operate when the system pressure is very low, and energy waste caused by the fact that the winch brake 2 needs high system back pressure due to the fact that normal opening is guaranteed is reduced. Meanwhile, the low-pressure control oil circuit 4 of the system is additionally arranged to provide low-pressure control oil for the hoisting brake 2, so that the hoisting main oil circuit does not directly control the hoisting brake 2 to be opened or closed any more, the phenomenon that the hoisting brake 2 is opened or closed in a vibrating manner due to load fluctuation can be avoided, and the stability of the hoisting system is improved. The hydraulic control system of the main valve belongs to a conventional hydraulic component, and under the technical concept of the invention, a person skilled in the art can specifically apply the main valve to the winch hydraulic system of the invention, and the description is omitted; further, the hoist motor 9 may employ a bidirectional hydraulic motor.

In addition, the oil drain port T1 is provided on the hoisting motor 9, and the oil drain port T1 of the hoisting motor 9 may be connected to the oil leakage path 100, or the oil drain port T1 of the hoisting motor 9 may be directly connected to the oil tank. The oil return port T of the hoist brake valve 3 may be connected to the leak oil path 100 or may be directly connected to the oil tank.

According to the invention, the pressure maintaining oil path is arranged between the oil inlet P of the winch brake valve 3 and the second oil port B of the winch balance valve, so that pre-pressure is provided for the winch motor 9, and thus, collision and pressure fluctuation generated when a connecting part is converted from a floating state to a close fit state due to internal leakage of the winch motor 9 can be effectively reduced. Furthermore, a damper 6 can be arranged on the pressure maintaining oil circuit to limit the flow of the oil in the pressure maintaining oil circuit, and the number of the dampers 6 can be one or more. The one-way valve 5 and the damper 6 connected with the one-way valve in series are arranged on the pressure-maintaining oil path, so that low-pressure control oil is provided for the starting and the stopping of the winch brake 2 without influencing the low-pressure control oil path 4 of the system while pre-pressure is provided for the winch motor 9; it is possible to prevent the influence of the high-pressure main oil passage on the control oil passage when the main oil passage pressure rises.

Generally, in order to filter impurities in the hydraulic oil, a filter 8 may be disposed on the pilot oil path between the third oil port X and the pilot control port of the balanced valve spool 1; a first one-way throttle valve is arranged between a pilot control port of the balance valve core 1 and the filter 8; a second one-way throttle valve is arranged between the spring control cavity of the balance valve core 1 and a second oil port B of the winch balance valve, and the one-way throttle valve is formed by connecting a one-way valve and a throttle valve in parallel; the reversing of the balance valve core 1 can be slowly carried out to enhance the running stability of the hoisting motor 9.

In order to better understand the technical scheme of the invention, the hoisting hydraulic system is described below by combining more comprehensive technical features.

As shown in fig. 2, in the hoisting hydraulic system according to the preferred embodiment of the present invention, the first working port A1 of the main valve is connected to the first working port a of the hoisting balance valve, the second working port B2 of the hoisting motor 9 is connected to the second working port B1 of the main valve, and the third working port X of the hoisting balance valve is also connected to the second working port B1 of the main valve; a first oil port A2 of the hoisting motor 9 is connected with a second oil port B of the hoisting balance valve; in the winch balance valve, a balance valve core 1 is arranged on an oil path between a first oil port A and a second oil port B of the winch balance valve, a pressure maintaining oil path is arranged between an oil inlet P of a winch brake valve 3 and the second oil port B of the winch balance valve, and the oil inlet P of the winch brake valve 3 is also connected with a system low-pressure control oil path 4, so that the system low-pressure control oil path 4 is communicated with a first oil port A2 of a winch motor 9, and an oil outlet K of the winch brake valve 3 is connected with a control port K1 of a winch brake 2 and used for providing low-pressure control oil for the winch brake 2; a first oil inlet a of the shuttle valve 7 is connected with a first oil port A of the winch balance valve, a second oil inlet b of the shuttle valve 7 is connected with a third oil port X of the winch balance valve, and an oil outlet c of the shuttle valve 7 is connected with a control port Z of the winch brake valve 3; an oil return port T of the winch brake valve 3 and an oil drain port T1 of the winch motor 9 are both connected with the leakage oil path 100.

In the process of operating the main winch control handle to move towards the winch ascending direction or operating the main winch control handle to move towards the winch descending direction, because the winch brake valve 3 and the winch brake 2 can both use springs with lower rigidity and have lower opening pressure, the whole winch hydraulic system can normally operate when the system pressure is very low, and the energy waste caused by the fact that the high system back pressure is needed for ensuring the normal opening of the winch brake 2 is reduced. Meanwhile, the low-pressure control oil circuit 4 of the system is additionally arranged to provide low-pressure control oil for the hoisting brake 2, so that the hoisting main oil circuit does not directly control the hoisting brake 2 to be opened or closed any more, the phenomenon that the hoisting brake 2 is opened or closed in a vibrating manner due to load fluctuation can be avoided, and the stability of the hoisting system is improved.

Meanwhile, as the pressure maintaining oil circuit is arranged, referring to fig. 3, in the process that the hoisting hydraulic system is lifted from a standstill state to a hoisting state, the hoisting motor key shaft 10a and the gear of the hoisting speed reducer 11a are in a tight meshing state, and as the hoisting brake 2 is not started, the hoisting motor 9 cannot rotate under the action of the hoisting brake 2, so that the system is kept stopped. When the winding motor 9 starts to rotate, the spline and the gear are always tightly attached to each other due to the pre-pressure provided by the pressure maintaining oil path from rest to the beginning of winding, and the spline and the gear cannot collide with each other; meanwhile, due to the existence of the check valve 5 and the flow-limiting damper 6, compared with the main oil way of the first working oil port A1 of the main valve, the oil flowing from the pressure-proof oil way to the first oil port A2 of the winch motor 9 is supplied with oil, the influence of the oil can be ignored, and the normal operation of the system low-pressure control oil way 4 and the winch brake valve 3 can not be influenced.

In the process of lowering the heavy load winch, the weight of the load heavy object 12a is large at this moment, namely, when the winch hydraulic system is heavy-loaded, the winch motor key shaft 10a is abutted to the upper side face of the gear teeth of the winch speed reducer 11a, and the winch motor 9 plays a supporting role in the process of lowering the winch at this moment, so that the heavy object is prevented from stalling when falling. Because of the pre-pressure provided by the pressure maintaining oil circuit, the spline and the gear are always tightly attached in the process of starting to rotate the hoisting motor 9, so that the collision between the spline and the gear cannot occur; when the winch motor 9 normally rotates, oil output by the system low-pressure control oil circuit 4 is converged into the main oil circuit, and enters the system along with the first working oil port A1 of the main valve in the main oil circuit to return oil.

In the process of lowering the light-load winch, referring to fig. 4, at this time, the mass of the load heavy object 12a is smaller, that is, the weight of the winch hydraulic system is light, in the process of gradually pressing the port B2 of the winch motor 9, the pre-pressure provided by the pressure maintaining oil line at the first oil port A2 of the winch motor 9 is gradually reduced in the process of opening the balance valve core 1, the pressure provided by the system low-pressure control oil line 4 has a buffering effect on the change of the gear gap position, so that the winch motor key shaft 10a is gradually abutted to the lower side surface of the gear teeth of the winch speed reducer 11a, and due to the smaller load, the abnormal sound caused by the collision between the gear teeth and the pressure fluctuation generated thereby can be reduced. Due to the existence of the damping 6, the oil flow of the system low-pressure control oil way 4 flowing to the main oil way is very small, and the pressure of the system low-pressure control oil way 4 cannot be reduced, so that the normal opening and closing of the winch brake are not influenced.

Therefore, part of oil is introduced from the system low-pressure control oil circuit 4 and enters the first oil port A2 of the hoisting motor 9, so that splines and gears in the hoisting motor and the hoisting speed reducer can be tightly attached. The clearance can be eliminated in advance in the process of lifting the hoisting hydraulic system from rest to hoisting and in the process of lowering the heavy-load hoisting, so that the collision generated when the spline and the gear are in a close fit state from a floating state is avoided; in the process of lowering the light-load winch, the change of the gap position of the connection part of the spline and the gear can be buffered. Therefore, collision and pressure fluctuation generated when the connecting parts are converted from a floating state to a tightly attached state due to internal leakage of the hoisting motor 9 can be effectively reduced, the stability of a hoisting hydraulic system can be greatly improved, and the service life of the hoisting speed reducer is prolonged.

The hoisting hydraulic system provided by the invention can be applied to hoisting engineering machinery such as automobile cranes, crawler cranes and the like, so that the hoisting engineering machinery has better working stability, and the internal abnormal sound of the hoisting engineering machinery and the pressure fluctuation generated by the internal abnormal sound are smaller.

It should be noted that, the hoisting engineering machinery such as the automobile crane, the crawler crane and the like usually has a main hoisting system and an auxiliary hoisting system, the main hoisting system and the auxiliary hoisting system have two sets of hoisting hydraulic systems with the same design, and the main hoisting system and the auxiliary hoisting system can adopt the hoisting balance valve and the hoisting hydraulic systems of the invention.

The preferred embodiments of the present invention have been described in detail with reference to the accompanying drawings, however, the present invention is not limited to the specific details of the above embodiments, and various simple modifications can be made to the technical solution of the present invention within the technical idea of the present invention, and these simple modifications are within the protective scope of the present invention.

It should be noted that the various features described in the foregoing embodiments may be combined in any suitable manner without contradiction. The invention is not described in detail in order to avoid unnecessary repetition.

In addition, any combination of the various embodiments of the present invention is also possible, and the same should be considered as the disclosure of the present invention as long as it does not depart from the spirit of the present invention.

Claims

1. The utility model provides a hoist balanced valve, its characterized in that, is including balanced case (1), hoist brake valve (3), first hydraulic fluid port (A) and second hydraulic fluid port (B) that are used for controlling hoist stopper (2), balanced case (1) is arranged on the oil circuit between first hydraulic fluid port (A) of hoist balanced valve and its second hydraulic fluid port (B), hoist brake valve (3) are including being used for oil inlet (P) of being connected with system low pressure control oil circuit (4), the oil inlet (P) of hoist brake valve (3) with be provided with the pressurize oil circuit between the second hydraulic fluid port (B) of hoist balanced valve, be equipped with pressurize check valve (5) on the oil circuit to can make hydraulic oil by oil inlet (P) one-way output of hoist brake valve (3) arrives the second hydraulic fluid port (B) of hoist balanced valve.

2. Winch balance valve according to claim 1, characterised in that a damper (6) is also provided on the oil-holding circuit.

3. The winch balance valve according to claim 1 or 2, further comprising a third oil port (X) and a shuttle valve (7), wherein the shuttle valve (7) comprises a first oil inlet (a) connected with the first oil port (a) of the winch balance valve, a second oil inlet (b) connected with the third oil port (X) of the winch balance valve, and an oil outlet (c) connected with the control port (Z) of the winch brake valve (3).

4. The hoisting balance valve according to claim 3, wherein the third oil port (X) of the hoisting balance valve is connected with the pilot control port of the balance spool (1).

5. The hoisting balance valve according to claim 4, characterized in that a filter (8) is arranged on the pilot oil path between the third oil port (X) of the hoisting balance valve and the pilot control port of the balance valve spool (1).

6. Winch balance valve according to claim 1 or 2, characterized in that the winch brake valve (3) comprises an oil outlet (K) for connection with a control port (K1) of the winch brake (2).

7. The winch hydraulic system is characterized by comprising a winch motor (9), a main valve and a winch balance valve according to any one of claims 1 to 6, wherein a first working oil port (A1) of the main valve is connected with a first oil port (A) of the winch balance valve, a second working oil port (B1) of the main valve is connected with a third oil port (X) of the winch balance valve and a second oil port (B2) of the winch motor (9) respectively, and the first oil port (A2) of the winch motor (9) is connected with the second oil port (B) of the winch balance valve.

8. Hoisting hydraulic system according to claim 7, characterized in that the hoisting motor (9) is provided with an oil drain (T1).

9. Hoisting hydraulic system according to claim 8, characterized in that the oil drain (T1) of the hoisting motor (9) is connected to a leakage oil circuit (100).

10. Hoisting work machine, characterized in that it comprises a hoisting hydraulic system according to any one of claims 7-9.