Hydraulic flow control valve, hydraulic control system and working machine

Abstract

The hydraulic flow control valve, the hydraulic control system and the engineering machinery provided by the embodiment of the present application relate to the field of engineering machinery. The hydraulic flow control valve comprises a valve body, a main valve core, a lifting valve core, a reset spring and a plug. The valve body is provided with a first connecting end for connecting with a first oil passage and a second connecting end for connecting with a second oil passage. The main valve core is arranged in the valve body and is provided with an internal oil passage comprising a first channel and a second channel which are in communication with each other. The lifting valve core is slidably arranged in the second channel. The reset spring is abutted between the lifting valve core and the plug and is used for abutting the lifting valve core on an end face of the second channel close to the first channel. The lifting valve core is used for allowing the hydraulic oil to flow from the second oil passage into the first oil passage and not to flow reversely. The embodiment of the present application can realize mutual oil supply between oil cylinders, save energy and save space.

Description

Technical Field

[0001] This invention relates to the field of engineering machinery, and more specifically, to a hydraulic flow control valve, a hydraulic control system, and engineering machinery. Background Technology

[0002] Existing hydraulic control systems in engineering machinery, when multiple cylinders operate simultaneously (i.e., in compound operations), can only supply hydraulic fluid to each cylinder itself, not multiple cylinders simultaneously. Alternatively, two cylinders can be connected via external pipes or external valve blocks to the main valve, achieving a one-to-one hydraulic supply. This method is complex, relatively simple in function, and limited to one-to-one cylinder hydraulic supply, which has certain limitations for machinery with limited installation space. Summary of the Invention

[0003] The purpose of this invention is to provide a hydraulic flow control valve, a hydraulic control system, and engineering machinery, which can realize mutual oil supply between cylinders, save energy, and save space.

[0004] The embodiments of the present invention are implemented as follows:

[0005] In a first aspect, embodiments of the present invention provide a hydraulic flow control valve, comprising: a valve body, a main valve core, a lifting valve core, a return spring, and a plug;

[0006] The valve body is provided with a first connection end for connecting to the first oil passage and a second connection end for connecting to the second oil passage;

[0007] The main valve core is disposed in the valve body and is provided with an internal oil passage. The internal oil passage includes a first channel and a second channel that are interconnected. The first channel is close to the first connection end, and the cross-sectional dimension of the second channel is larger than that of the first channel.

[0008] The lifting valve core is slidably disposed in the second channel, the plug is sealed at the port of the second channel away from the first channel, and the return spring is held between the lifting valve core and the plug to make the lifting valve core hold against the end face of the second channel near the first channel;

[0009] The lifting valve core is used to allow the hydraulic oil in the second oil passage to flow along the second connecting end, the internal oil passage and the first connecting end to the first oil passage; and the lifting valve core is also used to allow the hydraulic oil in the first oil passage to flow along the first connecting end and the first channel to the second channel and the lifting valve core.

[0010] In an optional embodiment, the lifting valve core includes a tapered portion and a sliding portion connected to each other. The tapered portion can extend into the first channel, and the sliding portion is slidably disposed in the second channel. The return spring abuts against the sliding portion and the plug.

[0011] In an optional embodiment, the sliding part is provided with a receiving cavity, the valve cavity of the lifting valve core is connected to the receiving cavity, the cross-sectional dimension of the receiving cavity is larger than the cross-sectional dimension of the first channel, and the reset spring is partially housed in the receiving cavity.

[0012] In an optional embodiment, a stepped portion is formed between the first channel and the second channel, the stepped portion having an inclined surface that partially conforms to the tapered surface of the tapered portion.

[0013] In an optional embodiment, an opening is provided between the tapered portion and the sliding portion.

[0014] In an optional embodiment, the main valve core is provided with a combination hole, which communicates with the first channel and is used to regulate the flow rate of hydraulic oil flowing out of or into the first channel.

[0015] In an optional embodiment, the main valve core is further provided with a fluid passage, which is connected to the second channel and located near the second connection end, for allowing hydraulic oil in the second oil passage to flow into the internal oil passage.

[0016] Secondly, embodiments of the present invention provide a hydraulic control system, including a hydraulic cylinder, a rod chamber, a pilot control handle, and a hydraulic flow control valve as described in any of the foregoing embodiments. The hydraulic cylinder is connected to the first connecting end, the rod chamber is connected to the second connecting end, and the pilot control handle is used to control the main valve core.

[0017] In an optional embodiment, there are multiple hydraulic cylinders, rod chambers, pilot control handles, and hydraulic flow control valves, with multiple hydraulic flow control valves connected accordingly.

[0018] Thirdly, embodiments of the present invention provide an engineering machine that includes a hydraulic flow control valve as described in any of the foregoing embodiments; or, the engineering machine includes a hydraulic control system as described in the foregoing embodiments.

[0019] The beneficial effects of this invention are as follows: The main valve core has an internal oil passage, which includes a first channel and a second channel that are interconnected, with the cross-sectional dimension of the first channel being smaller than that of the second channel. A lifting valve core is disposed within the second channel, and a compression spring abuts against the lifting valve core and the plug. When the hydraulic flow control valve is operating, the oil in the second oil passage enters the lifting valve core and the second channel (the gap formed between the lifting valve core and the second channel) through the second connecting end. At this time, the high-pressure oil in the second channel pushes the lifting valve core to compress the compression spring, causing the oil to flow to the first channel and then through the first connecting end to the first oil passage, thus achieving the "regeneration" and reuse of the oil. When the hydraulic oil in the first oil passage enters the internal oil passage of the main valve core through the first connecting end, the oil flows from the first channel into the second channel and into the lifting valve core. The difference in the area of ​​the oil acting before and after the lifting valve core effectively prevents the oil from reversing and opening the valve core, thus preventing it from flowing from the second connecting end to the second oil passage. This invention enables flow reuse when the hydraulic control system is in complex compound motion, thereby saving energy. Attached Figure Description

[0020] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of the present invention and should not be regarded as a limitation on the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0021] Figure 1 This is a schematic diagram of the structure of a hydraulic flow control valve provided in an embodiment of the present invention;

[0022] Figure 2 This is a schematic diagram of the structure of the hydraulic control system provided in an embodiment of the present invention;

[0023] Figure 3 This is a schematic diagram of the structure of the lift valve core provided in an embodiment of the present invention.

[0024] Icons: 11-First hydraulic cylinder; 12-First pilot control handle; 13-First directional control valve; 14-Second hydraulic cylinder; 15-Second pilot control handle; 16-Second directional control valve; 17-Third hydraulic cylinder; 18-Third pilot control handle; 19-Third directional control valve; 20-Fourth hydraulic cylinder; 21-Fourth pilot control handle; 22-Fourth directional control valve; 23-Hydraulic pump; 24-Bypass valve; 100-Hydraulic flow control valve; 110-Valve body; 111-First connecting end; 112-Second connecting end; 120-Main valve core; 121-Internal oil passage; 1211-First channel; 1212-Second channel; 122-Combination hole; 123-Through hole; 130-Lift valve core; 131-Conical part; 132-Sliding part; 133-Accommodating cavity; 134-Opening; 40-Return spring; 150-Plug. Detailed Implementation

[0025] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, 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 components of the embodiments of the present invention described and shown in the accompanying drawings can generally be arranged and designed in various different configurations.

[0026] Therefore, the following detailed description of the embodiments of the invention provided in the accompanying drawings is not intended to limit the scope of the claimed invention, but merely to illustrate selected embodiments of the invention. All other embodiments obtained by those skilled in the art based on the embodiments of the invention without inventive effort are within the scope of protection of the invention.

[0027] It should be noted that similar labels and letters in the following figures indicate similar items. Therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures.

[0028] In the description of this invention, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, or the orientation or positional relationship commonly used when the product of this invention is in use. They are only for the convenience of describing this invention and simplifying 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, and therefore should not be construed as a limitation of this invention. In addition, the terms "first," "second," "third," etc., are only used to distinguish descriptions and should not be construed as indicating or implying relative importance.

[0029] Furthermore, terms such as "horizontal" and "vertical" do not imply that components must be absolutely horizontal or suspended, but rather that they can be slightly tilted. For example, "horizontal" simply means that its direction is more horizontal than "vertical," and does not mean that the structure must be completely horizontal, but can be slightly tilted.

[0030] In the description of this invention, it should also be noted that, unless otherwise explicitly specified and limited, the terms "set," "install," "connect," and "link" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0031] Please see Figure 1 This invention provides a hydraulic flow control valve 100, which can be applied to hydraulic control systems, such as the hydraulic control systems of construction machinery. The construction machinery could be an excavator, etc. This hydraulic flow control valve 100 can achieve flow reuse when the hydraulic control system is in complex compound motion, thereby saving energy.

[0032] like Figure 2 As shown, the hydraulic flow control valve 100 provided in this embodiment of the invention can be applied in a hydraulic control system, such as... Figure 2 The hydraulic control system shown includes a first hydraulic cylinder 11, a first pilot control handle 12, a first directional control valve 13, a second hydraulic cylinder 14, a second pilot control handle 15, a second directional control valve 16, a third hydraulic cylinder 17, a third pilot control handle 18, a third directional control valve 19, a fourth hydraulic cylinder 20, a fourth pilot control handle 21, a fourth directional control valve 22, a hydraulic pump 23, a bypass valve 24, and several interface relief valves. The first hydraulic cylinder 11, the first pilot control handle 12, and the first directional control valve 13 are correspondingly connected; the second hydraulic cylinder 14, the second pilot control handle 15, and the second directional control valve 16 are correspondingly connected; the third hydraulic cylinder 17, the third pilot control handle 18, and the third directional control valve 19 are correspondingly connected; the fourth hydraulic cylinder 20, the fourth pilot control handle 21, and the fourth directional control valve 22 are correspondingly connected; and the first directional control valve 13, the second directional control valve 16, the third directional control valve 19, and the fourth directional control valve 22 are correspondingly connected. The connection method of the above components can be found in [reference needed]. Figure 2 .

[0033] The first directional control valve 13, the second directional control valve 16, the third directional control valve 19, and the fourth directional control valve 22 mentioned above are hydraulic flow control valves 100 provided in the embodiments of the present invention.

[0034] When at least two of the first pilot control handle 12, the second pilot control handle 15, the third pilot control handle 18, and the fourth pilot control handle 21 are activated simultaneously, the corresponding handle signals are converted into electrical signals to control the proportional pressure reducing solenoid valve to move the corresponding directional control valve, thus performing a combined action. Simultaneously, the corresponding signal is also transmitted to the bypass valve 24 core, which closes. The hydraulic pump 23 no longer returns the hydraulic fluid to the oil tank through all the directional control valves; instead, the supplied hydraulic fluid enters each cylinder to provide the power for its operation.

[0035] Please continue reading. Figure 1 In this embodiment of the invention, the hydraulic flow control valve 100 includes: a valve body 110, a main valve core 120, a lift valve core 130, a return spring 40, and a plug 150; the valve body 110 is provided with a first connecting end 111 for connecting to a first oil passage and a second connecting end 112 for connecting to a second oil passage; the main valve core 120 is disposed within the valve body 110 and is provided with an internal oil passage 121, the internal oil passage 121 including a first channel 1211 and a second channel 1212 that are interconnected, wherein the first channel 1211 is close to the first connecting end 111, and the cross-sectional dimension of the second channel 1212 is larger than the cross-sectional dimension of the first channel 1211; the lift valve core 130... The valve core 130 is slidably disposed within the second channel 1212. The plug 150 seals the port of the second channel 1212 away from the first channel 1211. The return spring 40 abuts against the lift valve core 130 and the plug 150, so that the lift valve core 130 abuts against the end face of the second channel 1212 near the first channel 1211. The lift valve core 130 is used to allow the hydraulic oil in the second oil passage to flow along the second connecting end 112, the internal oil passage 121 and the first connecting end 111 to the first oil passage. In addition, the lift valve core 130 is also used to allow the hydraulic oil in the first oil passage to flow along the first connecting end 111 and the first channel 1211 to the second channel 1212 and the lift valve core 130.

[0036] In other words, the lifting valve core 130 can enable the internal oil passage 121 of the main valve core 120 to be unidirectionally open, allowing the hydraulic oil in the second oil passage to flow into the first oil passage through the internal oil passage 121 of the main valve core 120, thus achieving flow regeneration; while when the hydraulic oil flows from the first oil passage into the main valve core 120, the lifting valve core 130 can prevent the hydraulic oil from flowing into the second oil passage.

[0037] When the hydraulic flow control valve 100 is applied to a hydraulic control system, the first connection end 111 can be connected to a hydraulic cylinder, and the second connection end 112 can be connected to a rod chamber or a rodless chamber to recover energy from the rod chamber or rodless chamber.

[0038] It should be understood that the hydraulic flow control valve 100 provided in this embodiment of the invention has an internal oil passage 121 within the main valve core 120. This internal oil passage 121 includes a first channel 1211 and a second channel 1212 that are interconnected, and the cross-sectional dimension of the first channel 1211 is smaller than that of the second channel 1212. A lift valve core 130 is disposed within the second channel 1212, and a compression spring abuts against the lift valve core 130 and the plug 150. When the hydraulic flow control valve 100 is in operation, the oil in the second oil passage enters the lift valve core 130 and the second channel 1212 (the gap formed between the lift valve core 130 and the second channel 1212) through the second connecting end 112. At this time, the high-pressure oil in the second channel 1212 pushes the lift valve core 130 to compress the compression spring, thereby causing the oil to flow to the first channel 1211, and then to the first oil passage through the first connecting end 111, thus realizing the "regeneration" and utilization of the oil. When the hydraulic oil in the first oil passage enters the internal oil passage 121 of the main valve core 120 through the first connecting end 111, the oil flows from the first channel 1211 into the second channel 1212 and then into the lift valve core 130. The difference in the area of ​​the oil acting before and after the lift valve core 130 effectively prevents the oil from reversing and opening the valve core, thus preventing it from flowing from the second connecting end 112 into the second oil passage. This hydraulic flow control valve 100 can achieve flow reuse when the hydraulic control system is in a complex compound motion, thereby saving energy.

[0039] In the prior art corresponding to the embodiments of the present invention, such as Figure 2 The hydraulic control system shown (where the directional control valve is a conventional directional control valve) controls the flow of oil supplied from hydraulic pump 23 to the first cylinder as a first hydraulic directional control valve, and controls the flow of oil supplied from hydraulic pump 23 to the second cylinder as a second cylinder directional control valve, and so on, with a third cylinder directional control valve, a third directional cylinder control valve, and so on. When the hydraulic pressure in the rod chamber (or rodless chamber) of the first cylinder reaches a certain high pressure, the rod chamber and rodless chamber of that cylinder are connected, serving as a hydraulic replenishment mechanism. For example, when applied to an excavator in construction machinery, as the rod chamber descends, the oil pressure in the rodless chamber is very high due to gravity. At this time, the rodless chamber and rod chamber are connected through an external or internal mechanism of a multi-way valve, realizing the supply of high-pressure hydraulic oil from the rodless chamber to the rod chamber, i.e., the function of flow regeneration, preventing the rod chamber from cavitating due to excessive speed, and saving flow.

[0040] However, in this existing technology, when multiple cylinders operate simultaneously, i.e., in a compound operation, only the cylinder itself can be supplied with oil; multiple cylinders cannot be supplied with oil simultaneously. Alternatively, the cylinders can be connected to the outside of the main valve via external pipes or external valve blocks. This method is structurally complex and functionally limited, only enabling one-to-one oil supply to each cylinder, and it has certain limitations for machinery with limited installation space.

[0041] For embodiments of the present invention, please refer to [link / reference]. Figure 2 The directional control valve is the hydraulic flow control valve 100 provided in the embodiment of the present invention. When at least two of the first, second, third and fourth cylinders are in operation at the same time, that is, when the relevant engineering machinery performs complex compound actions, regardless of the oil pressure in the return oil chamber of the other cylinders, as long as the hydraulic pressure of the return oil in one cylinder is too high, the hydraulic oil that was originally going to return to the oil tank can be fully and effectively reused to achieve flow reuse.

[0042] Please see Figure 3 In an optional embodiment, the lifting valve core 130 may include a tapered portion 131 and a sliding portion 132 connected to each other. The tapered portion 131 can extend into the first channel 1211, and the sliding portion 132 is slidably disposed in the second channel 1212. The return spring 40 abuts against the sliding portion 132 and the plug 150.

[0043] Furthermore, the sliding part 132 is provided with a receiving cavity 133, the valve cavity of the lifting valve core 130 is connected to the receiving cavity 133, the cross-sectional dimension of the receiving cavity 133 is larger than the cross-sectional dimension of the first channel 1211, and the return spring 40 is partially housed in the receiving cavity 133.

[0044] Furthermore, a stepped portion is formed between the first channel 1211 and the second channel 1212, and the stepped portion is provided with an inclined surface that partially conforms to the conical surface of the conical portion 131.

[0045] Optionally, an opening 134 is provided between the tapered portion 131 and the sliding portion 132, which allows oil to flow into the valve chamber of the second channel 1212 and the lifting valve core 130, thereby pushing the lifting valve core 130 to compress the compression spring.

[0046] In an optional embodiment, the main valve core 120 is provided with a combination hole 122, which communicates with the first channel 1211 and is used to regulate the flow rate of hydraulic oil flowing out of or into the first channel 1211. In this embodiment of the invention, the number of combination holes 122 is not specifically limited, and the pilot control handle can control the number of combination holes 122 used, thereby achieving precise control of the amount of oil regeneration flow.

[0047] In an optional embodiment, the main valve core 120 is also provided with a fluid passage 123, which is connected to the second channel 1212 and is close to the second connection end 112, for allowing hydraulic oil in the second oil passage to flow into the internal oil passage 121.

[0048] This invention provides a hydraulic control system, which includes a hydraulic cylinder, a rod chamber, a pilot control handle, and a hydraulic flow control valve 100 as described in any of the foregoing embodiments. The hydraulic cylinder is connected to a first connecting end 111, the rod chamber is connected to a second connecting end 112, and the pilot control handle is used to control the main valve core 120.

[0049] In an optional embodiment, there are multiple hydraulic cylinders, rod chambers, pilot control handles, and hydraulic flow control valves 100, with the multiple hydraulic flow control valves 100 being connected accordingly.

[0050] This invention provides an engineering machinery, including a hydraulic flow control valve 100 of any of the foregoing embodiments; or, the engineering machinery includes a hydraulic control system of the foregoing embodiments.

[0051] The beneficial effects of this embodiment of the invention are as follows: An internal oil passage 121 is provided within the main valve core 120. This internal oil passage 121 includes a first channel 1211 and a second channel 1212 that are interconnected, and the cross-sectional dimension of the first channel 1211 is smaller than that of the second channel 1212. A lift valve core 130 is disposed within the second channel 1212, and a compression spring abuts against the lift valve core 130 and the plug 150. When the hydraulic flow control valve 100 is operating, the oil in the second oil passage enters the lift valve core 130 and the second channel 1212 (the gap formed between the lift valve core 130 and the second channel 1212) through the second connecting end 112. At this time, the high-pressure oil in the second channel 1212 pushes the lift valve core 130 to compress the compression spring, thereby causing the oil to flow to the first channel 1211, and then to the first oil passage through the first connecting end 111, thus realizing the "regeneration" and utilization of the oil. When the hydraulic oil in the first oil passage enters the internal oil passage 121 of the main valve core 120 through the first connecting end 111, the oil flows from the first channel 1211 into the second channel 1212 and then into the lift valve core 130. The difference in the area of ​​the oil acting before and after the lift valve core 130 effectively prevents the oil from reversing and pushing open the valve core, thus preventing it from flowing from the second connecting end 112 into the second oil passage. This embodiment of the invention enables flow reuse during complex compound movements in the hydraulic control system, thereby saving energy.

[0052] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A hydraulic control system, characterized in that, include: The hydraulic cylinder and multiple working components, each of the working components including a rod chamber, a pilot control handle and a hydraulic flow control valve (100); The hydraulic flow control valve (100) includes: valve body (110), main valve core (120), lifting valve core (130), return spring (40) and plug (150); The valve body (110) is provided with a first connection end (111) for connecting to the first oil passage and a second connection end (112) for connecting to the second oil passage; The main valve core (120) is disposed inside the valve body (110) and is provided with an internal oil passage (121). The internal oil passage (121) includes a first channel (1211) and a second channel (1212) that are interconnected. The first channel (1211) is close to the first connecting end (111), and the cross-sectional dimension of the second channel (1212) is larger than that of the first channel (1211). The lifting valve core (130) is slidably disposed in the second channel (1212), the plug (150) is sealed at the port of the second channel (1212) away from the first channel (1211), and the return spring (40) abuts between the lifting valve core (130) and the plug (150) to make the lifting valve core (130) abut against the end face of the second channel (1212) near the first channel (1211); The lifting valve core (130) is used to allow the hydraulic oil in the second oil passage to flow along the second connecting end (112), the internal oil passage (121), and the first connecting end (111) to the first oil passage; and the lifting valve core (130) is also used to allow the hydraulic oil in the first oil passage to flow along the first connecting end (111), the first channel (1211), to the second channel (1212), and the lifting valve core (130); The lifting valve core (130) includes a tapered portion (131) and a sliding portion (132) connected to each other. The tapered portion (131) can extend into the first channel (1211), and the sliding portion (132) is slidably disposed in the second channel (1212). The return spring (40) abuts against the sliding portion (132) and the plug (150). An opening (134) is provided between the tapered portion (131) and the sliding portion (132); The opening (134) is annular, the maximum cross-sectional diameter of the tapered part (131) is the same as the cross-sectional diameter of the opening (134), and the cross-sectional diameter of the sliding part (132) is greater than the cross-sectional diameter of the opening (134). A stepped portion is formed between the first channel (1211) and the second channel (1212), and the stepped portion is provided with an inclined surface that partially conforms to the conical surface of the conical portion (131); In each of the working components, the rod chamber is connected to the second connecting end (112), and the pilot control handle is used to control the main valve core (120); Each of the hydraulic flow control valves (100) has an oil supply port on its valve body (110). The hydraulic cylinder is connected to the oil supply port of each valve body (110) through the main oil supply circuit. The hydraulic cylinder is connected to the first oil passage of each valve body (110) through the supplementary oil circuit. The supplementary oil circuit is unidirectionally connected to the main oil supply circuit through a check valve.

2. The hydraulic control system according to claim 1, characterized in that, The sliding part (132) is provided with a receiving cavity (133), the valve cavity of the lifting valve core (130) is connected to the receiving cavity (133), the cross-sectional dimension of the receiving cavity (133) is larger than the cross-sectional dimension of the first channel (1211), and the reset spring (40) is partially housed in the receiving cavity (133).

3. The hydraulic control system according to claim 1 or 2, characterized in that, The main valve core (120) is provided with a combination hole (122), which is connected to the first channel (1211) and is used to regulate the flow rate of hydraulic oil flowing out of or into the first channel (1211).

4. The hydraulic control system according to claim 1 or 2, characterized in that, The main valve core (120) is also provided with a liquid passage (123), which is connected to the second channel (1212) and is close to the second connection end (112) for allowing hydraulic oil in the second oil passage to flow into the internal oil passage (121).

5. An engineering machinery, characterized in that, The hydraulic control system includes any one of claims 1-4.

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