Unauthorized control valve, hydraulic system and crane

Abstract

The invention discloses an unauthorized control valve, a hydraulic system and a crane. The unauthorized control valve comprises a valve body, a reversing valve, a one-way valve and a compensation valve, the valve body is provided with a first load feedback port, a first control oil port, a second control oil port, a third oil inlet and a second load feedback port; an oil inlet of the one-way valve is connected with the second load feedback port, and an oil outlet of the one-way valve is connected with the first load feedback port; an oil inlet of the reversing valve is connected with the third oil inlet, an oil outlet of the reversing valve is connected to an oil way between the first load feedback port and an oil outlet of the one-way valve, the non-spring end of the reversing valve is connected with an oil outlet of the compensation valve and the non-spring end of the compensation valve, and the spring end of the reversing valve is connected to the second load feedback port; the spring end of the compensation valve is connected to an oil way between the second load feedback port and the oil inlet of the one-way valve, the oil inlet of the compensation valve is connected to the first control oil port, and the oil outlet of the compensation valve is connected to the second control oil port. The working efficiency of the main hydraulic system can be improved, the calorific value of the whole hydraulic system is reduced, and the service life of a sealing piece of the whole hydraulic system is prolonged.

Description

Technical Field

[0001] This invention belongs to the field of engineering machinery technology, specifically relating to an overstepping control valve, a hydraulic system, and a crane. Background Technology

[0002] Currently, the hydraulic system of cranes mainly includes a main hydraulic system and a slewing hydraulic system. The oil pump sources of the two are completely independent and the hydraulic oil circuits are not connected to each other. Therefore, when the crane moves, there will be no impact from the movement of the two systems.

[0003] like Figure 1 As shown, the main hydraulic system's operation control is as follows:

[0004] First, the crane's (extension-and-wind-jack) hydraulic system opens the flow area by controlling the valve stem of the hydraulic multi-way valve. The main hydraulic system automatically matches the flow rate entering the actuator based on the load sensitivity characteristics, thereby realizing the extension and retraction of the luffing cylinder and the lifting and lowering of the winch motor. Second, the crane's (extension-and-wind-jack) hydraulic system closes the flow area by controlling the valve stem of the hydraulic multi-way valve. The main hydraulic system automatically matches the flow rate entering the actuator based on the load sensitivity characteristics, thereby stopping the extension and retraction of the luffing cylinder and the lifting and lowering of the winch motor.

[0005] The slewing hydraulic system's motion control is as follows:

[0006] First, the rotary hydraulic system opens the flow area by controlling the valve stem of the rotary control valve to open it. Based on its throttling characteristics, the system automatically matches the flow rate entering the actuator, thus achieving left and right rotary motion. Second, the rotary hydraulic system closes the flow area by controlling the valve stem of the rotary control valve to close it. Based on its throttling characteristics, the system automatically matches the flow rate entering the actuator, thus stopping the left and right rotary motion.

[0007] It is evident that existing crane hydraulic system solutions have the following drawbacks:

[0008] (1) The rotary hydraulic system adopts throttling speed regulation technology. The rotary controllability is greatly affected by the load and return oil pressure changes, and the speed regulation range is inconsistent for light and heavy loads.

[0009] (2) Currently, the main hydraulic system and the slewing hydraulic system of the crane are independent, resulting in low system integration and insufficient improvement in the operating efficiency of the main system.

[0010] (3) During the lifting and hoisting combined operation, the slewing action is often at high engine speed and heavy load micro-motion, which causes most of the hydraulic oil in the slewing hydraulic system using throttling speed regulation technology to flow back into the oil tank through high pressure bypass, resulting in a large energy loss and a high system thermal equilibrium temperature, which can lead to seal failure in the long term. Summary of the Invention

[0011] To address the aforementioned issues, this invention proposes an overriding control valve, a hydraulic system, and a crane. By adding an overriding control valve and streamlining the pipeline connections, the impact on the slewing operation feel is optimized, the operating efficiency of the main hydraulic system is improved, the heat generation of the hydraulic system is reduced, and the lifespan of the hydraulic system seals is extended.

[0012] To achieve the above-mentioned technical objectives and effects, the present invention is implemented through the following technical solution:

[0013] In a first aspect, the present invention provides an overstepping control valve, comprising: a valve body, and a directional valve, a check valve and a compensation valve disposed within the valve body;

[0014] The valve body is provided with a first load feedback port, a first control oil port, a second control oil port, a third oil inlet, and a second load feedback port;

[0015] The oil inlet of the one-way valve is connected to the second load feedback port, and its oil outlet is connected to the first load feedback port.

[0016] The oil inlet of the reversing valve is connected to the third oil inlet, its oil outlet is connected to the oil circuit between the first load feedback port and the oil outlet of the check valve, its non-spring end is connected to the oil outlet of the compensation valve and the non-spring end of the compensation valve respectively, and its spring end is connected to the second load feedback port.

[0017] The spring end of the compensation valve is connected to the oil circuit between the second load feedback port and the oil inlet of the one-way valve, its oil inlet is connected to the first control oil port, and its oil outlet is connected to the second control oil port.

[0018] In conjunction with the first aspect, optionally, the state balance formula of the compensation valve is:

[0019] Pr2 = LSr2 + S,

[0020] Wherein, Pr2 is the pressure at the second control port, LSr2 is the pressure at the second load feedback port, and S is the pressure generated by the spring in the compensation valve.

[0021] In a second aspect, the present invention provides a hydraulic system with an overriding control valve, comprising:

[0022] Multi-way valve;

[0023] The hydraulic pump is connected to the first oil inlet of the multi-way valve, and the first oil inlet is also connected to the oil inlets of the luffing working link and the telescopic working link of the multi-way valve.

[0024] The winch hydraulic pump is connected to the second oil inlet of the multi-way valve, and the second oil inlet is also connected to the winch working connection oil inlet of the multi-way valve.

[0025] Rotary control valve;

[0026] The overstepping control valve described in any one of the first aspects has its first load feedback port connected to the load feedback port of the multi-way valve. Its first load feedback port, first control oil port and third oil inlet are all located in the oil circuit between the oil outlet of the stretch hydraulic pump and the first oil inlet of the multi-way valve. Its second control oil port is connected to the oil inlet of the rotary control valve. Its second load feedback port is also connected to the oil circuit between the rotary control valve and the rotary motor.

[0027] A rotary motor is connected to the rotary control valve.

[0028] In conjunction with the second aspect, optionally, when the crane is started and in standby mode, the hydraulic oil from the extension hydraulic pump and the winch hydraulic pump enters the multi-way valve through the first and second inlets of the multi-way valve, respectively, and then enters the return port of the multi-way valve through the first and second diverter valves, finally returning to the oil tank through the return port; wherein, the first diverter valve is connected in parallel with the winch working link, and the second diverter valve is connected in parallel with the extension working link and the luffing working link;

[0029] There is no pressure at the first load feedback port, which causes the hydraulic oil of the stretch hydraulic pump to enter the first control oil port, and then enter the directional valve through the compensation valve, so that the directional valve is in the reversing position and does not affect the standby state of the crane hydraulic system.

[0030] In conjunction with the second aspect, optionally, when the crane operates the slewing control valve alone, the hydraulic oil in the stretching hydraulic pump enters the first control port, flows through the compensation valve to the second control port, and then enters the slewing control valve and the slewing motor.

[0031] In conjunction with the second aspect, optionally, when the hydraulic oil flowing out of the stretch hydraulic pump is sufficient, the excess hydraulic oil returns to the oil tank through the diverter valve in the multi-way valve, and the reversing valve is in the reversing position.

[0032] In conjunction with the second aspect, optionally, when the hydraulic oil flowing out of the extension hydraulic pump is insufficient, the reversing valve is proportionally opened, so that the hydraulic oil at the third inlet of the overriding control valve enters the first load feedback port through the outlet of the reversing valve, and gradually closes the first and second diverter valves in the multi-way valve, so that more hydraulic oil enters the first control port. The first diverter valve is connected in parallel with the hoisting working link, and the second diverter valve is connected in parallel with the telescopic working link and the luffing working link.

[0033] In conjunction with the second aspect, optionally, when the telescopic and / or luffing actions are combined with the slewing action, if the load on the slewing motor is large, resulting in high pressure at the second control port, the pressure of the slewing motor is output to the first load feedback port through the second load feedback port in the overriding control valve via a check valve. The post-valve compensation characteristic of the multi-way valve is used to reduce the opening of the compensator in the telescopic working combination and / or luffing working combination, so that the hydraulic oil of the telescopic hydraulic pump continues to enter the slewing motor.

[0034] If flow saturation occurs, causing the directional valve in the overriding control valve to gradually transition from the directional position to the neutral position, then the first and second diverter valves in the multi-way valve are closed, and the opening of the corresponding compensator is further reduced to promote the hydraulic oil flowing out of the extension hydraulic pump into the rotary motor; wherein, the first diverter valve is connected in parallel with the winch working link, and the second diverter valve is connected in parallel with the telescopic working link and the luffing working link.

[0035] If the flow rate is increased by increasing the speed of the stretch hydraulic pump after the flow saturation occurs, the hydraulic oil flowing out of the stretch hydraulic pump will preferentially enter the rotary motor. As the flow rate entering the rotary motor increases, the directional valve will gradually switch to the reversing position. At the same time, the opening of the corresponding compensator in the multi-way valve will be increased, and the first and second diverter valves will be gradually opened.

[0036] In conjunction with the second aspect, optionally, when the slewing action is performed alone, the confluence valve in the multi-way valve is in the closed state, and the extension hydraulic pump supplies hydraulic oil solely to the slewing control valve;

[0037] When the telescopic and / or luffing operation is combined with the slewing operation, the confluence valve in the multi-way valve is in the open state, and the telescopic hydraulic pump and the winch hydraulic pump simultaneously supply hydraulic oil to the slewing control valve.

[0038] When the hoist operates alone, the confluence valve in the multi-way valve is in the open state, and the extension hydraulic pump and the hoist hydraulic pump simultaneously supply hydraulic oil to the rotary control valve.

[0039] When the hoisting action and the slewing action are combined, the confluence valve in the multi-way valve is in the open state, and the hoisting hydraulic pump supplies hydraulic oil to the slewing control valve separately.

[0040] Thirdly, the present invention provides a crane including the overriding control valve as described in any one of the first aspects, or a hydraulic system having the overriding control valve as described in any one of the second aspects.

[0041] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0042] This invention proposes an overriding control valve, a hydraulic system, and a crane. By adding an overriding control valve and adjusting the pipeline connection, the impact on the slewing operation feel is optimized, the operating efficiency of the main hydraulic system is improved, the heat generation of the hydraulic system is reduced, and the life of the hydraulic system seals of the whole machine is extended.

[0043] This invention integrates the rotary hydraulic system into the main hydraulic system, resulting in a high degree of integration, improved operating efficiency of the main hydraulic system, and simplification of pipelines and other auxiliary components.

[0044] In this invention, the rotary hydraulic system adopts load-sensitive control. Even when the rotary motion is in a high-speed, heavy-load, micro-motion state during hoisting and compound operations, most of the hydraulic oil can be utilized by the extension and winch motion, reducing energy loss, lowering the system's thermal equilibrium temperature, and extending the working time of the seals. Attached Figure Description

[0045] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the embodiments will be briefly described below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort, wherein:

[0046] Figure 1 This is a schematic diagram of the structure of a crane hydraulic system in the prior art;

[0047] Figure 2 This is a schematic diagram of a hydraulic system with an overriding control valve according to an embodiment of the present invention;

[0048] Figure 3 This is a schematic diagram of the structure of an overstepping control valve according to an embodiment of the present invention;

[0049] In the picture:

[0050] Figure 1 In the middle: 1-First winch motor, 2-First winch motor, 3-Luffing cylinder, 4-Telescopic cylinder, 5-Multi-way valve, 6-Oil tank, 7-Telescopic hydraulic pump, 8-Winding hydraulic pump, 9-Slewing hydraulic pump, 10-Slewing control valve, 11-Slewing motor;

[0051] Figure 2 and Figure 3 middle:

[0052] 1-First winch motor, 2-Second winch motor, 3-Luffing cylinder, 4-Telescopic cylinder, 5-Multi-way valve, 6-Oil tank, 7-Extension hydraulic pump, 8-Winding hydraulic pump, 9-Overstepping control valve, 10-Slewing control valve, 11-Slewing motor, 9-1 Directional valve, 9-2 Compensating valve, 9-3 Check valve, Lsr1-First load feedback port, Pr1-First control port, Pr2-Second control port, P3-Overstepping control valve inlet, Lsr2-Second load feedback port, P1-First inlet of multi-way valve, P2-Second inlet of multi-way valve, RF1-First diverter valve, RF2-Second diverter valve. Detailed Implementation

[0053] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. The following description of at least one exemplary embodiment is merely illustrative and is in no way intended to limit the present invention or its application or use. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0054] Unless otherwise specifically stated, the relative arrangement, numerical expressions, and values ​​of the components and steps set forth in these embodiments do not limit the scope of the invention. It should also be understood that, for ease of description, the dimensions of the various parts shown in the drawings are not drawn to actual scale. Techniques, methods, and devices known to those skilled in the art may not be discussed in detail, but where appropriate, such techniques, methods, and devices should be considered part of the specification. In all examples shown and discussed herein, any specific values ​​should be interpreted as merely exemplary and not as limitations. Therefore, other examples of exemplary embodiments may include different values. It should be noted that similar reference numerals and letters in the following figures denote similar items; therefore, once an item is defined in one figure, it need not be further discussed in subsequent figures.

[0055] In the description of this invention, "several" means one or more, "multiple" means two or more, "greater than," "less than," and "exceeding" are understood to exclude the stated number, while "above," "below," and "within" are understood to include the stated number. The use of "first" and "second" in the description is merely for distinguishing technical features and should not be construed as indicating or implying relative importance, or implicitly indicating the number of indicated technical features, or implicitly indicating the order of the indicated technical features.

[0056] In the description of this invention, the terms "one embodiment," "some embodiments," "illustrative embodiment," "example," "specific example," or "some examples," etc., refer to specific features, structures, materials, or characteristics described in connection with that embodiment or example, which are included in at least one embodiment or example of the invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0057] The application principle of the present invention will be described in detail below with reference to the accompanying drawings.

[0058] Example 1

[0059] This invention provides an overreach control valve 9, such as... Figure 3 As shown, it includes: a valve body, and a reversing valve 9-1, a check valve 9-3 and a compensation valve 9-2 disposed in the valve body;

[0060] The valve body is provided with a first load feedback port Lsr1, a first control oil port Pr1, a second control oil port Pr2, a third oil inlet P3, and a second load feedback port Lsr2.

[0061] The oil inlet of the one-way valve 9-3 is connected to the second load feedback port Lsr2, and its oil outlet is connected to the first load feedback port Lsr1.

[0062] The oil inlet of the reversing valve 9-1 is connected to the third oil inlet P3, its oil outlet is connected to the oil circuit between the first load feedback port Lsr1 and the oil outlet of the check valve 9-3, its non-spring end is connected to the oil outlet of the compensation valve 9-2 and the non-spring end of the compensation valve 9-2 respectively, and its spring end is connected to the second load feedback port Lsr2.

[0063] The spring end of the compensation valve 9-2 is connected to the oil circuit between the second load feedback port Lsr2 and the oil inlet of the one-way valve 9-3. Its oil inlet is connected to the first control oil port Pr1, and its oil outlet is connected to the second control oil port Pr2.

[0064] By applying the overriding control valve 9 in the embodiments of the present invention to the hydraulic system of a crane, the main hydraulic system and the slewing hydraulic system can be integrated, thereby optimizing the impact on the slewing operation feel, improving the operating efficiency of the main hydraulic system, reducing the heat generation of the hydraulic system, and extending the life of the seals of the whole machine hydraulic system.

[0065] In one specific embodiment of the present invention, the state balance formula of the compensation valve 9-2 is:

[0066] Pr2 = LSr2 + S,

[0067] Wherein, Pr2 is the pressure at the second control port Pr2, LSr2 is the pressure at the second load feedback port Lsr2, and S is the pressure generated by the spring in the compensation valve 9-2.

[0068] Example 2

[0069] This invention provides a hydraulic system with an overriding control valve 9, such as... Figure 2 As shown, it includes:

[0070] Multi-way valve 5;

[0071] The extendable hydraulic pump 7 is connected to the first oil inlet P1 of the multi-way valve 5, and the first oil inlet P1 is also connected to the oil inlets of the luffing working link and the telescopic working link of the multi-way valve 5; for example Figure 2 As shown, a telescopic hydraulic cylinder 4 is connected to the telescopic working link; a luffing hydraulic cylinder 3 is connected to the luffing working link.

[0072] The winch hydraulic pump 8 is connected to the second oil inlet P2 of the multi-way valve 5, and the second oil inlet P2 is also connected to the winch working connection oil inlet of the multi-way valve 5; for example Figure 2 As shown, the number of winch working links is 2, and the first winch motor 1 and the second winch motor 2 are respectively connected to the two winch working links;

[0073] Rotary control valve 10;

[0074] The overstepping control valve 9 described in Example 1 has its first load feedback port Lsr1 connected to the load feedback port Ls of the multi-way valve 5. Its first load feedback port Lsr1, first control oil port Pr1, and third oil inlet P3 are all located in the oil circuit between the oil outlet of the stretch hydraulic pump 7 and the first oil inlet P1 of the multi-way valve 5. Its second control oil port Pr2 is connected to the oil inlet of the rotary control valve 10. Its second load feedback port Lsr2 is also connected to the oil circuit between the rotary control valve 10 and the rotary motor 11.

[0075] The rotary motor 11 is connected to the rotary control valve 10.

[0076] The above solution integrates the main hydraulic system and the slewing hydraulic system of the crane, avoiding the need for separate pump sources, pipelines, and other auxiliary components for the slewing system. This reduces costs, simplifies assembly, and avoids risks such as oil leaks in the pipelines. Furthermore, the slewing hydraulic system employs load-sensitive control, ensuring that even during high-speed, heavy-load, and micro-motion slewing operations, most of the flow can be utilized by the extension and retraction winch, reducing energy loss, lowering the system's thermal equilibrium temperature, and extending the working time of the seals.

[0077] In one specific embodiment of the present invention, when the crane is started and in standby mode, the hydraulic oil from the extension hydraulic pump 7 and the winch hydraulic pump 8 enters the main valve of the multi-way valve 5 through the first inlet P1 and the second inlet P2, and then enters the return port T of the multi-way valve 5 through the first diverter valve RF1 and the second diverter valve RF2, and finally returns to the oil tank 6 through the return port T; wherein, the first diverter valve RF1 is connected in parallel with the winch working link, and the second diverter valve RF2 is connected in parallel with the extension working link and the luffing working link;

[0078] There is no pressure at the first load feedback port Lsr1, which causes the hydraulic oil of the stretch hydraulic pump 7 to enter the first control port Pr1, and then enter the reversing valve 9-1 through the compensation valve 9-2, so that the reversing valve 9-1 is in the reversing position and does not affect the standby state of the crane hydraulic system.

[0079] Based on the above solution, it is possible to ensure that when the crane is started and in standby mode, it does not affect the standby state of the crane's hydraulic system.

[0080] In one specific embodiment of the present invention, when the crane operates the slewing control valve 10 alone, the hydraulic oil in the stretch hydraulic pump 7 enters the first control port Pr1, flows through the compensation valve 9-2 to the second control port Pr2, and then enters the slewing control valve 10 and the slewing motor 11.

[0081] When the hydraulic oil flowing out of the stretch hydraulic pump 7 is sufficient, the excess hydraulic oil returns to the oil tank 6 through the diversion valve in the multi-way valve 5, and the reversing valve 9-1 is in the reversing position.

[0082] When the hydraulic oil flowing out of the extension hydraulic pump 7 is insufficient, the reversing valve 9-1 is proportionally opened, so that the hydraulic oil at the third inlet P3 of the overriding control valve 9 enters the first load feedback port Lsr1 through the outlet of the reversing valve 9-1, and gradually closes the first diverter valve RF1 and the second diverter valve RF2 in the multi-way valve 5, so that more hydraulic oil enters the first control port Pr1. The first diverter valve RF1 is connected in parallel with the hoisting working link, and the second diverter valve RF2 is connected in parallel with the telescopic working link and the luffing working link.

[0083] In the above scheme, the directional valve 9-1 uses the differential pressure detection of the rotary control valve 10 to control the opening size of the diversion valves RF1 and RF2 in the multi-way valve 5, thereby realizing the rotary action.

[0084] In one specific embodiment of the present invention, when the telescopic action and / or luffing operation are combined with the slewing action, if the load on the slewing motor 11 is large, resulting in high pressure at the second control port Pr2, the pressure of the slewing motor 11 is output to the first load feedback port Lsr1 through the second load feedback port (Lsr2) in the overriding control valve 9 via the check valve 9-3. The post-valve compensation characteristic of the multi-way valve 5 is used to reduce the opening of the compensator in the telescopic operation and / or luffing operation, so that the hydraulic oil of the telescopic hydraulic pump 7 continues to enter the slewing motor 11.

[0085] If flow saturation occurs, causing the reversing valve 9-1 in the overriding control valve 9 to gradually transition from the reversing position to the neutral position, then the first diverter valve RF1 and the second diverter valve RF2 in the multi-way valve 5 are closed, and the opening of the corresponding compensator is further reduced to promote the hydraulic oil flowing out of the extension hydraulic pump 7 into the rotary motor 11; wherein, the first diverter valve RF1 is connected in parallel with the hoisting working link, and the second diverter valve RF2 is connected in parallel with the telescopic working link and the luffing working link;

[0086] If the flow rate is increased by increasing the speed of the stretch hydraulic pump 7 after the flow rate becomes saturated, the hydraulic oil flowing out of the stretch hydraulic pump 7 will preferentially enter the rotary motor 11. As the flow rate entering the rotary motor 11 increases, the reversing valve 9-1 will gradually switch to the reversing position. At the same time, the opening of the corresponding compensator in the multi-way valve 5 will be increased, and the first diverter valve RF1 and the second diverter valve RF2 will be gradually opened.

[0087] In one specific embodiment of the present invention, when the slewing action is performed alone, the confluence valve in the multi-way valve 5 is in the closed state, and the extension hydraulic pump 7 supplies hydraulic oil to the slewing control valve 10 alone.

[0088] When the telescopic action and / or luffing operation are combined with the slewing action, the confluence valve in the multi-way valve 5 is in the open state, and the telescopic hydraulic pump 7 and the winch hydraulic pump 8 simultaneously supply hydraulic oil to the slewing control valve 10.

[0089] When the hoist operates alone, the confluence valve in the multi-way valve 5 is in the open state, and the extension hydraulic pump 7 and the hoist hydraulic pump 8 simultaneously supply hydraulic oil to the rotary control valve 10.

[0090] When the hoisting action and the slewing action are combined, the confluence valve in the multi-way valve 5 is in the open state, and the hoisting hydraulic pump 8 supplies hydraulic oil to the slewing control valve 10 separately.

[0091] Based on the above scheme, it is possible to use the extension hydraulic pump 7 and / or the winch hydraulic pump 8 to supply oil to the rotary hydraulic system.

[0092] Example 3

[0093] This invention provides a crane, including the overriding control valve 9 as described in any one of Embodiment 1, or a hydraulic system having the overriding control valve 9 as described in any one of Embodiment 2.

[0094] In the description of this application, it should be understood that the terms "center", "longitudinal", "lateral", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only used to facilitate the description of the present invention and to simplify the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limiting the scope of protection of the present invention.

[0095] The foregoing has shown and described the basic principles, main features, and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited to the above embodiments. The embodiments and descriptions in the specification are merely illustrative of the principles of the invention. Various changes and modifications can be made to the invention without departing from its spirit and scope, and all such changes and modifications fall within the scope of the present invention as claimed. The scope of protection of this invention is defined by the appended claims and their equivalents.

Claims

1. An overstepping control valve, characterized in that, include: Valve body, and a directional valve (9-1), a check valve (9-3), and a compensation valve (9-2) disposed within the valve body. The valve body is provided with a first load feedback port (Lsr1), a first control oil port (Pr1), a second control oil port (Pr2), a third oil inlet (P3), and a second load feedback port (Lsr2). The oil inlet of the one-way valve (9-3) is connected to the second load feedback port (Lsr2), and its oil outlet is connected to the first load feedback port (Lsr1). The oil inlet of the reversing valve (9-1) is connected to the third oil inlet (P3), and its oil outlet is connected to the oil circuit between the first load feedback port (Lsr1) and the oil outlet of the check valve (9-3). Its non-spring end is connected to the oil outlet of the compensation valve (9-2) and the non-spring end of the compensation valve (9-2) respectively, and its spring end is connected to the second load feedback port (Lsr2). The spring end of the compensation valve (9-2) is connected to the oil circuit between the second load feedback port (Lsr2) and the oil inlet of the check valve (9-3), and its oil inlet is connected to the first control oil port (Pr1), and its oil outlet is connected to the second control oil port (Pr2).

2. The overstepping control valve according to claim 1, wherein the state balance formula of the compensation valve (9-2) is: Pr2 = LSr2 + S, in, Pr2 is the pressure at the second control port (Pr2), LSr2 is the pressure at the second load feedback port (Lsr2), and S is the pressure generated by the spring in the compensation valve (9-2).

3. A hydraulic system with an overriding control valve, characterized in that, include: Multi-way valve (5); The extension hydraulic pump (7) is connected to the first oil inlet (P1) of the multi-way valve, and the first oil inlet (P1) is also connected to the luffing working link and the telescopic working link oil inlet of the multi-way valve (5). The winch hydraulic pump (8) is connected to the second oil inlet (P2) of the multi-way valve, and the second oil inlet (P2) is also connected to the winch working oil inlet of the multi-way valve (5); Rotary control valve (10); The overstepping control valve (9) as described in claim 1 or 2 has its first load feedback port (Lsr1) connected to the load feedback port (Ls) of the multi-way valve (5), and its first load feedback port (Lsr1), first control oil port (Pr1) and third oil inlet (P3) are all located in the oil line between the oil outlet of the stretch hydraulic pump (7) and the first oil inlet (P1) of the multi-way valve. Its second control oil port (Pr2) is connected to the oil inlet of the rotary control valve (10), and its second load feedback port (Lsr2) is also connected to the oil line between the rotary control valve (10) and the rotary motor (11). A rotary motor (11) is connected to the rotary control valve (10).

4. A hydraulic system with an overriding control valve according to claim 3, characterized in that, When the crane is started and in standby mode, the hydraulic oil from the extension hydraulic pump (7) and the winch hydraulic pump (8) enters the multi-way valve (5) through the first inlet (P1) and the second inlet (P2) of the multi-way valve, respectively, and enters the return port (T) of the multi-way valve (5) through the first diverter valve (RF1) and the second diverter valve (RF2) in the multi-way valve (5), and finally returns to the oil tank (6) through the return port (T); wherein, the first diverter valve (RF1) is connected in parallel with the winch working link, and the second diverter valve (RF2) is connected in parallel with the extension working link and the luffing working link; There is no pressure at the first load feedback port (Lsr1), which causes the hydraulic oil of the stretch hydraulic pump (7) to enter the first control oil port (Pr1), and then enter the reversing valve (9-1) through the compensation valve (9-2), so that the reversing valve (9-1) is in the reversing position and does not affect the standby state of the crane hydraulic system.

5. A hydraulic system with an overriding control valve according to claim 3, characterized in that, When the crane operates the slewing control valve (10) alone, the hydraulic oil in the stretch hydraulic pump (7) enters the first control port (Pr1), flows through the compensation valve (9-2) to the second control port (Pr2), and then enters the slewing control valve (10) and the slewing motor (11).

6. A hydraulic system with an overriding control valve according to claim 5, characterized in that, When the hydraulic oil flowing out of the stretch hydraulic pump (7) is sufficient, the excess hydraulic oil returns to the oil tank (6) through the diverter valve in the multi-way valve (5), and the reversing valve (9-1) is in the reversing position.

7. A hydraulic system with an overriding control valve according to claim 5, characterized in that, When the hydraulic oil flowing out of the extension hydraulic pump (7) is insufficient, the reversing valve (9-1) is proportionally opened, so that the hydraulic oil at the third oil inlet (P3) of the overriding control valve (9) enters the first load feedback port (Lsr1) through the oil outlet of the reversing valve (9-1), and gradually closes the first diverter valve (RF1) and the second diverter valve (RF2) in the multi-way valve (5), so that more hydraulic oil enters the first control oil port (Pr1), wherein the first diverter valve (RF1) is connected in parallel with the hoisting working link, and the second diverter valve (RF2) is connected in parallel with the telescopic working link and the luffing working link.

8. A hydraulic system with an overriding control valve according to claim 3, characterized in that, When the telescopic and / or luffing action is combined with the slewing action, if the load on the slewing motor (11) is large, resulting in high pressure at the second control port (Pr2), the pressure of the slewing motor (11) will output pressure feedback to the first load feedback port (Lsr1) through the second load feedback port (Lsr2) in the overriding control valve (9) via the check valve (9-3). The valve post-compensation characteristic of the multi-way valve (5) is used to reduce the opening of the compensator in the telescopic working combination and / or luffing working combination, so that the hydraulic oil of the telescopic hydraulic pump (7) continues to enter the slewing motor (11). If flow saturation occurs, causing the reversing valve (9-1) in the overriding control valve (9) to gradually transition from the reversing position to the neutral position, then the first diverter valve (RF1) and the second diverter valve (RF2) in the multi-way valve (5) are closed, and the opening of the corresponding compensator is further reduced to promote the hydraulic oil flowing out of the extension hydraulic pump (7) to enter the rotary motor (11); wherein, the first diverter valve (RF1) is connected in parallel with the hoisting working link, and the second diverter valve (RF2) is connected in parallel with the telescopic working link and the luffing working link; If the flow rate is increased by increasing the speed of the stretch hydraulic pump (7) after the flow rate is saturated, the hydraulic oil flowing out of the stretch hydraulic pump (7) will preferentially enter the rotary motor (11). As the flow rate entering the rotary motor (11) increases, the reversing valve (9-1) will gradually switch to the reversing position. At the same time, the opening of the corresponding compensator in the multi-way valve (5) will be increased, and the first diverter valve (RF1) and the second diverter valve (RF2) will be gradually opened.

9. A hydraulic system with an overriding control valve according to claim 3, characterized in that, When the slewing action is performed alone, the confluence valve in the multi-way valve (5) is closed, and the extension hydraulic pump (7) supplies hydraulic oil to the slewing control valve (10) alone. When the telescopic action and / or luffing operation are combined with the slewing action, the confluence valve in the multi-way valve (5) is in the open state, and the telescopic hydraulic pump (7) and the winch hydraulic pump (8) simultaneously supply hydraulic oil to the slewing control valve (10). When the hoist operates alone, the confluence valve in the multi-way valve (5) is in the open state, and the extension hydraulic pump (7) and the hoist hydraulic pump (8) simultaneously supply hydraulic oil to the rotary control valve (10). When the hoisting action and the slewing action are combined, the confluence valve in the multi-way valve (5) is in the open state, and the hoisting hydraulic pump (8) supplies hydraulic oil to the slewing control valve (10) separately.

10. A crane, characterized in that, The system includes the overriding control valve (9) according to any one of claims 1-2, or the hydraulic system having the overriding control valve according to any one of claims 3-9.

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