Electro-hydraulic combined control flow valve

Abstract

The utility model relates to an electro-hydraulic combined control flow valve which comprises a valve body, a first control assembly, a second control assembly, an oil inlet and an oil drainage port are arranged in the valve body, the first control assembly comprises a valve rod, an oil inlet hole is formed in the side face close to one end of the valve rod, the oil inlet hole of the valve rod is communicated with the oil inlet, and an oil outlet is formed in the other end of the valve rod. The space at one end of the oil outlet of the valve rod is communicated with a second control assembly through an oil way, the second control assembly is communicated with an oil drainage port, and the oil drainage port is communicated with the space on the outer side of the valve rod. According to the electro-hydraulic combined control flow valve, compared with a traditional cooling system, the plunger pump can rapidly adjust the rotating speed of the fan according to electric signals and needs, the phenomenon of supercooling or superheating caused by a fixed rotating speed cooling mode of a traditional mechanical fan is avoided, the cooling effect is greatly improved, waste of energy consumption of an engine is avoided, and the service life of the engine is prolonged. And an energy-saving mode of providing on demand is achieved.

Description

Technical Field

[0001] This utility model relates to the field of hydraulic piston pump technology, and in particular to an electro-hydraulic combined control flow valve. Background Technology

[0002] In the excavator industry, cooling system design is one of the core technologies for ensuring equipment reliability and efficient operation. With the increase in engine power, stricter environmental protection requirements, and more complex operating conditions, the design of cooling systems needs to comprehensively consider multiple aspects such as heat load matching, structural optimization, and intelligent control.

[0003] Traditional cooling systems use fans directly driven by the engine crankshaft, a classic mechanical design. The fan is connected to the crankshaft via a belt or gears, and the crankshaft's rotation directly drives the fan. The fan speed is proportional to the engine speed (RPM); the higher the engine speed, the faster the fan speed and the greater the cooling capacity. Traditional cooling systems are simple in structure, requiring no complex electronic control systems, relying on purely mechanical transmission, resulting in high reliability. They have low maintenance costs, few parts, a low failure rate, and are easy to repair and replace (e.g., replacing the belt). The fan starts immediately after the engine starts, without waiting for sensors or circuitry to activate.

[0004] However, traditional cooling systems are inefficient and prone to overheating. At high speeds, the fan may operate beyond its capacity, wasting engine power (approximately 5-10% of fuel consumption is used to drive the fan). Insufficient cooling occurs at low speeds or idling (such as in traffic jams), where the fan speed is low, reducing cooling capacity and potentially causing engine overheating. They are also noisy, with significant fan noise at high speeds, affecting driving comfort. Forced fan operation during cold starts prolongs engine warm-up time, increasing wear and emissions. Furthermore, they cannot dynamically adjust fan speed based on real-time temperature, relying on passive cooling.

[0005] The direct-drive fan cooling method is a classic solution from the mechanical era. Currently, some small and medium-sized excavators still use this method for heat dissipation, mainly because it is low-cost and simple to operate. However, medium and large equipment has high heat dissipation requirements and is sensitive to energy consumption, so there is an urgent need for a cooling system suitable for the medium and large excavator industry. Utility Model Content

[0006] To address the problems of inefficiency, wasted engine power, inability to dynamically adjust engine speed based on real-time temperature, and reliance on passive cooling in traditional cooling systems, an electro-hydraulic combined control flow valve is proposed.

[0007] The technical solution of this utility model is as follows: an electro-hydraulic combined control flow valve, including a valve body, inside which are provided a first control component, a second control component, an oil inlet and an oil outlet. The first control component includes a valve stem, with an oil inlet hole on the side near one end of the valve stem. The oil inlet hole of the valve stem is connected to the oil inlet. An oil outlet is provided at the other end of the valve stem. The space at one end of the oil outlet of the valve stem is connected to the second control component through an oil passage. The second control component is connected to the oil outlet. The oil outlet is connected to the outer space of the valve stem.

[0008] Preferably, the first control component further includes a first support, one end of which is fitted with the end of the valve stem that has an oil outlet, and the other end of the first support is an extension section. An inner elastic element is fitted on the outside of the extension section, and an outer elastic element is fitted on the outside of the inner elastic element. Two steps are provided around the root of the extension section of the first support. One end of the inner elastic element is fitted with the inner step, and one end of the outer elastic element is fitted with the outer step. The other ends of the inner and outer elastic elements are fitted with one end of a stop post, which is located inside the first adjustment component.

[0009] Preferably, the first adjusting component includes an adjusting seat, which is hollow inside. One end of the adjusting seat passes through the valve body. The stop post, the inner elastic element, and the outer elastic element are all disposed inside the adjusting seat. A first adjusting rod is provided on the side of the stop post away from the inner elastic element. A first locking element is sleeved on the outer side of the first adjusting rod near the adjusting seat.

[0010] Preferably, the valve body has a first plug inside, and the first plug is located on the side of the valve stem away from the first support.

[0011] Preferably, the second control component includes a valve core and a valve core seat. The valve core passes through the valve core seat. One end of the valve core is attached to one end of the second support. The other end of the second support is an extension. An elastic element is sleeved on the outside of the extension. One end of the elastic element is attached to the second support. The other end of the elastic element is attached to the second adjustment component. A magnetic element is provided at the end of the valve core seat away from the second support. The end of the valve core away from the second support is flush with the end face of the magnetic element. The oil drain port is connected to the space surrounding the elastic element.

[0012] Preferably, each end of the valve core is provided with a cylinder, the cross-sectional diameter of the cylinder near the second support is larger than the cross-sectional diameter of the cylinder near the magnetic component, and the cylinder near the second support is provided with a valve core groove, which is eyebrow-shaped.

[0013] Preferably, the second adjusting component includes a second plug, one end of which is inserted into the valve body, and a second adjusting rod is inserted inside the second plug. One end of the second adjusting rod is fitted with the end of the elastic element away from the second support, and a second locking element is sleeved on the outer side of the second adjusting rod near the second plug.

[0014] Preferably, the oil passage between the valve stem and the second control component is connected at the end of the oil passage away from the oil outlet to the sealed cylindrical space formed by the valve core groove and the valve core seat.

[0015] Preferably, the valve body is further provided with a first control port, which is connected to the servo chamber of the plunger pump, and a first throttling pin is provided inside the first control port.

[0016] Preferably, the valve body is further provided with a second control oil port, which is connected to the outer space of the second adjusting rod and the outer space of the valve stem, and a second throttling pin is provided inside the second control oil port.

[0017] The beneficial effects of this utility model are as follows: Compared with the traditional cooling system, the electro-hydraulic combined control flow valve provided by this utility model can quickly adjust the fan speed as needed according to the electrical signal, avoiding the overcooling or overheating phenomenon caused by the fixed speed cooling method of the traditional mechanical fan, greatly improving the cooling effect, avoiding the waste of engine energy consumption, and achieving the energy-saving mode of "providing on demand". Attached Figure Description

[0018] Figure 1 This is a schematic diagram of the electro-hydraulic combined control flow valve structure of this utility model;

[0019] Figure 2 This is a schematic diagram of the valve stem structure in the electro-hydraulic combined control flow valve of this utility model;

[0020] Figure 3 This is a schematic diagram of the valve core structure in the electro-hydraulic combined control flow valve of this utility model;

[0021] Figure 4 This is a hydraulic schematic diagram of the electro-hydraulic combined control flow valve integrated into a piston pump according to this utility model.

[0022] The component names corresponding to the various reference numerals in the diagram are as follows:

[0023] 1. Valve body; 2. First control component; 21. Valve stem; 211. Oil inlet; 212. Oil outlet; 22. Stop pin; 23. Outer elastic element; 24. Inner elastic element; 25. First support; 26. First adjustment component; 261. First adjustment rod; 262. First locking element; 263. Adjustment seat; 27. First plug; 3. Second control component; 31. Elastic element; 32. Second support; 33. Valve core; 331. Valve core groove; 34. Valve core seat; 35. Magnetic element; 36. Second adjustment component; 361. Second adjustment rod; 362. Second locking element; 363. Second plug; 4. Oil inlet; 5. First control oil port; 51. First throttle pin; 6. Second control oil port; 61. Second throttle pin; 7. Oil drain port. Detailed Implementation

[0024] The present invention will now be described in detail with reference to the accompanying drawings and specific embodiments. This embodiment is based on the technical solution of the present invention and provides detailed implementation methods and specific operating procedures; however, the scope of protection of the present invention is not limited to the following embodiments.

[0025] refer to Figure 1 , 2 As shown in the embodiment of this application, an electro-hydraulic combined control flow valve is disclosed, including a valve body 1. The valve body 1 is provided with a first control component 2, a second control component 3, an oil inlet 4, and an oil outlet 7. The first control component 2 includes a valve stem 21. An oil inlet hole 211 is provided on the side near one end of the valve stem 21. The oil inlet hole 211 of the valve stem 21 is connected to the oil inlet 4. An oil outlet 212 is provided at the other end of the valve stem 21. The space at one end of the oil outlet 212 of the valve stem 21 is connected to the second control component 3 through an oil passage. The second control component 3 is connected to the oil outlet 7. The oil outlet 7 is connected to the outer space of the valve stem 21, preventing the pressure oil on the left and right sides of the valve stem 21 from interfering with the left and right movement of the valve stem through the cylindrical surface.

[0026] The first control component 2 also includes a first support 25. One end of the first support 25 is provided with a groove, which fits with the end of the valve stem 21 that has an oil outlet. The other end of the first support 25 is an extension section. An inner elastic element 24 is sleeved on the outside of the extension section, and an outer elastic element 23 is sleeved on the outside of the inner elastic element 24. In this embodiment, both the inner elastic element 24 and the outer elastic element 23 are springs. Two steps are provided around the root of the extension section of the first support 25. One end of the inner elastic element 24 fits with the inner step, and one end of the outer elastic element 23 fits with the outer step. The first support 25 is used to support and fix the inner elastic element 24, the outer elastic element 23 and the valve stem 21. The other ends of the inner elastic element 24 and the outer elastic element 23 fit with one end of the stop post 22. The stop post 22 is located inside the first adjustment component 26.

[0027] The first adjusting assembly 26 includes an adjusting seat 263, which is hollow inside. One end of the adjusting seat 263 passes through the valve body 1. A sealing ring is provided at the connection between the adjusting seat 263 and the edge of the valve body 1 to seal the hydraulic oil through an angle seal. The stop post 22, the inner elastic element 24, and the outer elastic element 23 are all located inside the adjusting seat 263. A sealing ring is provided between the stop post 22 and the inner wall of the adjusting seat 263 to seal the hydraulic oil. A first adjusting rod 261 is provided on the side of the stop post 22 away from the inner elastic element 24. The first adjusting rod 261 is threadedly connected to the adjusting seat 263. A first locking element 262 is sleeved on the outer side of the first adjusting rod 261 near the adjusting seat 263. The first locking element 262 is threadedly connected to the first adjusting rod 261. After the first adjusting rod 261 is adjusted to a suitable position, the first locking element 262 locks the first adjusting rod 261. The first adjusting rod 261 can adjust the pre-pressure of the inner elastic element 24 and the outer elastic element 23 on one side of the valve stem 21.

[0028] The valve body 1 is provided with a first plug 27 inside. The first plug 27 is connected to the valve body 1 by threads. The first plug 27 is located on the side of the valve stem 21 away from the first support 25. A sealing gasket is provided at the connection between the first plug 27 and the valve body 1 for sealing the hydraulic oil.

[0029] refer to Figure 1 , 3 As shown, the second control component 3 includes a valve core 33 and a valve core seat 34. The valve core 33 passes through the valve core seat 34. One end of the valve core 33 is a groove that fits with one end of the second support 32. The other end of the second support 32 is an extension section. An elastic element 31 is sleeved on the outer side of the extension section. In this embodiment, the elastic element 31 is a spring. One end of the elastic element 31 fits with the second support 32, and the other end fits with the second adjusting component 36. A magnetic element 35 is provided at the end of the valve core seat 34 away from the second support 32. The magnetic element 35 is locked onto the valve core seat 34 by threads. In this embodiment, the magnetic element 35 is an electromagnet. The end of the valve core 33 away from the second support 32 is flush with the end face of the magnetic element 35. The drain port 7 is connected to the space surrounding the elastic element 31.

[0030] The valve core seat 34 is threaded inside the valve body 1. The valve core seat 34 has a groove on the outer side near the second support 32. A combined sealing ring is provided in the groove for sealing the hydraulic oil. A sealing ring is provided at the edge connection between the valve core seat 34 and the valve body 1 to seal the hydraulic oil by means of corner sealing.

[0031] Each end of the valve core 33 has a cylinder. The cross-sectional diameter of the cylinder near the second support 32 is larger than that of the cylinder near the magnetic component 35. The cylinder near the second support 32 has a valve core groove 331, which is eyebrow-shaped.

[0032] The second adjusting assembly 36 includes a second plug 363, which is threaded into the valve body 1. A second adjusting rod 361 passes through the second plug 363 and is threadedly connected to it. One end of the second adjusting rod 361 is fitted against the end of the elastic member 31 away from the second support 32. A groove is provided on the outer periphery of a section of the second adjusting rod 361 inside the valve body 1, and a sealing ring is provided in the groove to seal the hydraulic oil. A second locking member 362 is fitted on the outer side of the second adjusting rod 361 near the second plug 363. The second locking member 362 is threadedly connected to the second adjusting rod 361. After the second adjusting rod 361 is adjusted to a suitable position, the second locking member 362 locks the second adjusting rod 361. The second adjusting rod 361 can adjust the pre-pressure of the elastic member 31 on one side of the valve core 33.

[0033] The oil passage between the valve stem 21 and the second control component 3 has its end away from the oil outlet 212 connected to the sealed cylindrical space formed by the valve core groove 331 and the valve core seat 34.

[0034] The valve body 1 is also provided with a first control port 5, which is connected to the servo chamber of the plunger pump. The first control port 5 is provided with a first throttling nail 51, which is a throttling screw. The first throttling nail 51 is connected to the valve body 1 by threads.

[0035] The function of the first throttle pin 51: When the output flow of the plunger pump is 0, no pressure can be built up. Without the function of the first throttle pin 51, the swashplate will rapidly maximize its displacement under the action of the return spring. The swashplate's reaction speed is too fast, which is a shock to the entire system. Once the first throttle pin 51 is installed, the return speed of the hydraulic oil in the first control port 5 will be slowed down, and the system shock will be reduced.

[0036] The valve body 1 is also provided with a second control oil port 6. The second control oil port 6 is a process oil port and does not pass oil. The second control oil port 6 is connected to the outer space of the second adjusting rod 361 and the outer space of the valve stem 21. The second control oil port 6 is provided with a second throttling nail 61. The second throttling nail 61 is a throttling screw. The second throttling nail 61 is installed in the valve body 1 through cylindrical mating.

[0037] The function of the second throttling pin 61 is as follows: When the oil pressure from the inlet 4 enters the first control port 5 for variable control, it also passes through the second control port 6 of the second throttling pin 61. Since the second control port 6 is a fixed throttling point, a fixed pressure difference will be formed at the second control port 6. This pressure difference is the variable pressure entering the first control port 5. It can be seen that this pressure is related to the size of the second control port 6, but not to the size of the oil pressure. This avoids fluctuations in the control amplitude due to oil pressure fluctuations, and plays a role in stabilizing the control.

[0038] The oil inlet 4, the first control oil inlet 5, the second control oil inlet 6, and the oil drain 7 are all equipped with sealing rings at their connection points with the outside to seal the hydraulic oil.

[0039] The specific working principle is as follows:

[0040] refer to Figure 4 As shown, when the hydraulic oil temperature is low and the hydraulic system does not require cooling, the hydraulic oil P from the piston pump outlet reaches the cylindrical surface of the valve stem 21 through the valve body oil passage, enters the right end of the valve stem 21 through the oil inlet 211, and simultaneously reaches the left end of the valve stem 21 through the oil outlet 212. The hydraulic oil flowing into the left side of the valve stem 21 enters the sealed cylindrical space formed by the valve core 33 and the valve core seat 34 through the oil passage. Because the system oil temperature sensed by the temperature sensor is low, the controller, after receiving the temperature signal, requires the piston pump not to provide flow to the fan motor for cooling. At this time, the controller outputs a large current, and the electromagnet in the flow control valve receives the electrical signal. The magnetic component 35 extends with maximum force, pushing the valve core 33 to the right. The valve core 33 overcomes the spring force of the right elastic component 31 and moves to the right. When the eyebrow-shaped valve core groove 331 on the cylindrical surface exceeds the sealing cylindrical surface formed with the valve core seat 34, the oil pressure in the sealing cylindrical surface space will connect with the drain port 7, and the pressure will drop instantly. At this time, the pressure on the left side of the valve stem 21 will drop synchronously. For the valve stem 21, the pressure on the left side drops. Due to the presence of the oil outlet 212, the pressure on the right side of the valve stem 21 will not drop instantly. When the combined force of the hydraulic pressure on the left side of the valve stem 21 and the inner elastic element 23 and the outer elastic element 24 is less than the hydraulic pressure on the right side of the valve stem 21, the valve stem 21 moves to the left. The hydraulic oil in the oil inlet 4 enters the first control oil port 5 through the first throttle pin 51. The first control oil port 5 is connected to the servo chamber of the plunger pump, pushing the plunger pump swashplate angle to 0. At this time, the plunger pump has no flow output, the fan motor does not rotate, and the system is not cooled.

[0041] When the system oil temperature rises and requires slight cooling, the temperature sensor detects the temperature increase. After receiving the temperature signal, the controller outputs a current signal I (lower than the maximum current when cooling is not required). Due to the reduced current, the magnetic component 35 of the flow control valve electromagnet outputs a lower force. Under the action of the elastic component 31, the valve core 33 moves to the left. The eyebrow-shaped valve core groove 331 on the right side of the valve core 33 returns to the sealing cylinder and disconnects from the drain port 7. The pressure on the left side of the valve stem 21 increases instantaneously. For the valve stem 21, the pressure on the left and right sides is equal. Due to the spring action of the inner elastic component 23 and the outer elastic component 24 on the left side, the valve stem 21 will move to the right. The hydraulic oil in the plunger pump servo chamber returns to the drain port 7 through the first throttle pin 51. Under the action of the return spring inside the pump body, the plunger pump swashplate swings towards a large angle, increasing the output flow of the plunger pump, and the fan motor starts to run. When the rotational speed reaches a certain value, due to the motor's rotational resistance, the pressure at the oil inlet 4 also increases. There is a dimensional difference between the left and right cylindrical surfaces of the valve core 33. When the system pressure reaches a certain value, the force acting to the right on the area difference of the valve core 33, combined with the electromagnet force of the magnetic component 35, is greater than the spring force of the right elastic component 31. The valve core 33 moves to the right, and the eyebrow-shaped valve core groove 331 extends beyond the sealing cylindrical surface formed with the valve core seat 34. The pressure on the left side of the valve stem 21 decreases, and the valve stem 21 moves to the left. Control oil pressure enters the servo plunger chamber through the oil inlet 4, directing the output flow of the plunger pump... As the load decreases, the fan motor will stop accelerating and its speed will decrease. When the speed decreases, the load P decreases synchronously. The combined force of the force acting on the area difference of the valve core 33 and the electromagnet of the magnetic component 35 is less than the spring force of the elastic component 31 on the right. The valve core 33 moves to the left again, the pressure on the left side of the valve stem 21 increases, the valve stem 21 moves to the right, the output flow of the plunger pump increases again, and the fan motor starts to accelerate and rotate to cool again. This cycle repeats to achieve a certain temperature, that is, to output a certain fixed current. Under the basis of electro-hydraulic joint control, the fan motor operating speed remains constant.

[0042] When the system temperature is severely overheated, the controller requests the cooling system to output its maximum speed for cooling. At this time, the controller will not output current, the electromagnet of the magnetic component 35 on the flow control valve will not function, the magnetic component 35 will contract, and the valve core 33 will move to the left under the force of the elastic component 31. The pressure on the left side of the valve stem 21 will be the same as the pressure on the right side. Due to the large and small spring forces on the left side that compress the valve stem 21, the valve stem 21 will move to the right, and the hydraulic oil at the inlet 4 will not be able to enter the first control oil port 5. The swashplate angle of the plunger pump will increase, the output flow will increase, the fan motor speed will increase, and the load will increase synchronously. Since the area difference between the left and right cylindrical surfaces on the valve core 33 is small, without the auxiliary force of the electromagnet of the magnetic component 35, the valve core 33 cannot be pushed to the right to overcome the pressure relief of the elastic component 31 on the right side as the load increases. Therefore, the output flow of the plunger pump will continue to increase until the maximum flow, and the fan motor will run at its highest speed to quickly cool the severe overheating problem of the system.

[0043] The beneficial effects are:

[0044] This utility model provides an electro-hydraulic combined control flow valve. Compared with traditional cooling systems, the plunger pump can quickly adjust the fan speed as needed based on the electrical signal, avoiding overcooling or overheating caused by the fixed speed cooling method of traditional mechanical fans. This greatly improves the cooling effect, avoids the waste of engine energy, and achieves an energy-saving mode of "providing on demand".

[0045] It should be noted that the terms "vertical," "horizontal," "top," "bottom," "inner," and "outer," etc., indicating orientation or positional relationships are based on the orientation or positional relationships shown in the accompanying drawings. They are used only for the convenience of describing this utility model 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. Therefore, they should not be construed as limitations on this utility model. The terms "first," "second," etc., are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. "A plurality of" means two or more. "Installed," "connected," and "joined" should be interpreted broadly; for example, they can refer to a fixed connection, a detachable connection, or an integral connection.

[0046] The above description is merely a preferred embodiment of this utility model and is not intended to limit this utility model in any form or substance. It should be noted that those skilled in the art can make various improvements and additions without departing from this utility model, and these improvements and additions should also be considered within the protection scope of this utility model. Any modifications, alterations, and equivalent changes made by those skilled in the art without departing from the spirit and scope of this utility model using the disclosed technical content are equivalent embodiments of this utility model. Furthermore, any modifications, alterations, and evolutions made to the above embodiments based on the essential technology of this utility model are still within the scope of the technical solution of this utility model.

Claims

1. An electro-hydraulic combined control flow valve, characterized in that, The valve body (1) includes a first control component (2), a second control component (3), an oil inlet (4), and an oil drain (7). The first control component (2) includes a valve stem (21). An oil inlet (211) is provided on the side near one end of the valve stem (21). The oil inlet (211) of the valve stem (21) is connected to the oil inlet (4). An oil outlet (212) is provided at the other end of the valve stem (21). The space at one end of the oil outlet (212) of the valve stem (21) is connected to the second control component (3) through an oil passage. The second control component (3) is connected to the oil drain (7). The oil drain (7) is connected to the outer space of the valve stem (21).

2. The electro-hydraulic combined control flow valve according to claim 1, characterized in that, The first control component (2) further includes a first support (25). One end of the first support (25) is fitted with the end of the valve stem (21) that has an oil outlet. The other end of the first support (25) is an extension section. An inner elastic element (24) is fitted on the outside of the extension section. An outer elastic element (23) is fitted on the outside of the inner elastic element (24). Two steps are provided around the root of the extension section of the first support (25). One end of the inner elastic element (24) is fitted with the inner step. One end of the outer elastic element (23) is fitted with the outer step. The other ends of the inner elastic element (24) and the outer elastic element (23) are fitted with one end of the stop post (22). The stop post (22) is located inside the first adjustment component (26).

3. The electro-hydraulic combined control flow valve according to claim 2, characterized in that, The first adjustment component (26) includes an adjustment seat (263), which is hollow inside. One end of the adjustment seat (263) is inserted into the valve body (1). The stop post (22), the inner elastic member (24), and the outer elastic member (23) are all arranged inside the adjustment seat (263). A first adjustment rod (261) is provided on the side of the stop post (22) away from the inner elastic member (24). A first locking member (262) is sleeved on the outer side of the first adjustment rod (261) near the adjustment seat (263).

4. The electro-hydraulic combined control flow valve according to claim 2, characterized in that, The valve body (1) is provided with a first plug (27) inside, and the first plug (27) is located on the side of the valve stem (21) away from the first support (25).

5. The electro-hydraulic combined control flow valve according to claim 1, characterized in that, The second control component (3) includes a valve core (33) and a valve core seat (34). The valve core (33) is inserted inside the valve core seat (34). One end of the valve core (33) is attached to one end of the second support (32). The other end of the second support (32) is an extension section. An elastic element (31) is sleeved on the outside of the extension section. One end of the elastic element (31) is attached to the second support (32). The other end of the elastic element (31) is attached to the second adjustment component (36). A magnetic element (35) is provided at the end of the valve core seat (34) away from the second support (32). The end of the valve core (33) away from the second support (32) is flush with the end face of the magnetic element (35). The oil drain port (7) is connected to the space around the elastic element (31).

6. The electro-hydraulic combined control flow valve according to claim 5, characterized in that, The valve core (33) has a cylinder at each end. The cross-sectional diameter of the cylinder near the second support (32) is larger than that of the cylinder near the magnetic component (35). The cylinder near the second support (32) has a valve core groove (331), which is eyebrow-shaped.

7. The electro-hydraulic combined control flow valve according to claim 5, characterized in that, The second adjustment component (36) includes a second plug (363), one end of which is inserted into the valve body (1), and a second adjustment rod (361) is inserted inside the second plug (363). One end of the second adjustment rod (361) is fitted with the end of the elastic member (31) away from the second support (32), and a second locking member (362) is sleeved on the outer side of the second adjustment rod (361) near the second plug (363).

8. The electro-hydraulic combined control flow valve according to claim 6, characterized in that, The oil passage between the valve stem (21) and the second control component (3) is connected at one end of the oil passage away from the oil outlet (212) to the sealed cylindrical space formed by the valve core groove (331) and the valve core seat (34).

9. The electro-hydraulic combined control flow valve according to claim 1, characterized in that, The valve body (1) is also provided with a first control port (5), which is connected to the servo chamber of the plunger pump. The first control port (5) is provided with a first throttle pin (51).

10. The electro-hydraulic combined control flow valve according to claim 7, characterized in that, The valve body (1) is also provided with a second control oil port (6), which is connected to the outer space of the second adjusting rod (361) and the outer space of the valve stem (21). The second control oil port (6) is provided with a second throttle pin (61).

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