Closed hydraulic control system for a pneumatic actuator

Abstract

The application belongs to the technical field of closed hydraulic equipment, and discloses a closed hydraulic control system for a pneumatic actuator, which comprises a hydraulic cylinder, an oil tank and a pump body, and further comprises a one-way valve, a current collector and an electric control ball valve; wherein the oil tank is in conduction with the input end of the pump body through a corresponding pipeline. The above scheme draws out the hydraulic oil in the oil tank by closing the electric control ball valve and operating the pump body, and sends the hydraulic oil into the oil outlet through the pipeline, the one-way valve and the current collector; the hydraulic oil enters cavity one through the hydraulic oil channel to push the piston rod to retract the cylinder body; the hydraulic oil in cavity two is returned to the oil tank through the oil outlet and the corresponding pipeline; the whole system is in a closed circuit state, and external gas or impurities cannot enter the cylinder body to cause rust or damage in the cylinder body; the scheme adopts a closed hydraulic circuit, and solves the problem that moisture, dust or corrosive substances enter the cylinder to cause rust or damage in the cylinder body when one oil port of the single-direction driving hydraulic rod is connected to the atmosphere.

Description

Technical Field

[0001] This invention belongs to the technical field of closed-loop hydraulic equipment, specifically a closed-loop hydraulic control system for pneumatic actuators. Background Technology

[0002] Pressure cylinders are widely used in control systems. They can be used directly as a power source to drive hydraulic actuators or as a manual mechanism to drive pneumatic actuators.

[0003] Hydraulic cylinders typically have two ports connected to a hydraulic power unit, with a directional valve controlling the oil inlet and outlet to achieve piston rod extension and retraction. If only unidirectional drive is required, only one port needs to be connected to the hydraulic power unit, while the other port is open to the atmosphere, with a spring for reset. However, in this solution for unidirectional hydraulic cylinders, the open-to-atmosphere port creates a "breathing" effect, allowing moisture, dust, or corrosive substances to enter the cylinder. This can lead to rust, jamming, or even damage to the cylinder body or piston rod. The longer the stroke of the hydraulic cylinder, the more severe the problem becomes, and the larger the required oil tank volume.

[0004] Therefore, based on the above problems, a closed-loop hydraulic control system for pneumatic actuators is proposed. Summary of the Invention

[0005] To address the problems mentioned in the background art, the present invention provides a closed-loop hydraulic control system for pneumatic actuators, which solves the problem that moisture, dust, or corrosive substances can enter the cylinder and cause rust or damage to the cylinder body when one oil port of the unidirectional drive hydraulic rod is open to the atmosphere.

[0006] To achieve the above objectives, the present invention provides the following technical solution: a closed-loop hydraulic control system for a pneumatic actuator, comprising a hydraulic cylinder, an oil tank and a pump body, and further comprising: a check valve, a manifold and an electrically controlled ball valve; The oil tank is connected to the input end of the pump body through a corresponding pipe, and the output end of the pump body is connected to the collector in one direction through a corresponding pipe and a one-way valve. The oil tank can be connected to the collector through a corresponding pipe and an electrically controlled ball valve. The hydraulic cylinder includes a cylinder body and a piston rod movably sleeved inside it. The cylinder body has a hydraulic oil passage and an oil inlet connected to one end of the hydraulic oil passage. The cylinder body also has an oil outlet. The piston part of the piston rod divides the cylinder body into two spaces. The space where the piston rod part is located is cavity one and is connected to the hydraulic oil passage. The other space is cavity two and is connected to the oil outlet. The collector can be connected to the oil inlet through a pipe, and the oil outlet can be connected to the oil tank through a pipe; in the initial state, the piston rod has a tendency to move outward due to the elastic force of its own spring.

[0007] Preferably, the oil inlet is equipped with a sealing mechanism for sealing the oil inlet.

[0008] Preferably, a separator ring is fixedly installed in the oil inlet; the sealing mechanism includes a valve core assembly movably sleeved on the separator ring for dividing the oil inlet cavity into upper and lower parts, the bottom end of the valve core assembly is fixedly connected to a spring telescopic rod, and the bottom end of the spring telescopic rod is installed on the cylinder body. In the initial state, the spring telescopic rod can be compressed and contracted and stretched. The valve core assembly can connect the upper and lower parts of the oil delivery chamber when it moves up or down.

[0009] Preferably, the valve core assembly includes a valve core body fixedly installed at the output end of the spring telescopic rod, a spring piston rod movably installed in the valve core body, the diameter of the upper part of the spring piston rod being smaller than the diameter of the lower part, the top end of the spring piston rod penetrating the top of the valve core body, a plurality of spring pieces arranged in a ring array inside the valve core body, each spring piece being fixedly installed with a locking rod, one end of the locking rod being able to abut against the lower part of the spring piston rod, at which time the other end of the locking rod will extend to the outside of the valve core body and abut against the upper surface of the separator ring; After the spring piston rod moves downward, the spring plate springs back to its original position, allowing one end of the locking rod to abut against the upper part of the spring piston rod. At this time, the locking rod will retract into the valve core body.

[0010] Preferably, the top and bottom ends of the valve core body are chamfered.

[0011] Preferably, the diameter of the top end of the spring piston rod is larger than the diameter of its lower part, and the top end of the spring piston rod is the piston end; the locking rod is fitted with a sealing ring, and the valve core body is in a sealed state.

[0012] Preferably, a sealing valve one is provided at the outer end of the oil inlet, and a sealing valve two is provided at the outer end of the oil outlet.

[0013] Preferably, a one-way valve capable of unidirectional outward conduction is installed inside the oil outlet, and a micropore is formed in the middle of the one-way valve; The one-way valve is located at the inner end of the oil outlet, while the sealing valve is located at the outer end of the oil outlet.

[0014] Preferably, the fuel tank includes a tank body, and an annular cover is installed on the top of the tank body, with an elastic diaphragm for sealing the top of the tank body installed on the annular cover.

[0015] Compared with the prior art, the beneficial effects of the present invention are as follows: (1) The above scheme draws out the hydraulic oil from the tank by closing the electric ball valve and running the pump body. The hydraulic oil is sent into the oil inlet in one direction through the pipeline, check valve and manifold. The hydraulic oil enters the first cavity through the hydraulic oil passage and pushes the piston rod back into the cylinder. The hydraulic oil in the second cavity flows back to the tank through the oil outlet and the corresponding pipeline. The whole system is in a closed loop state, which avoids external gas or impurities from entering the cylinder and causing corrosion or damage to the cylinder. The scheme adopts a closed hydraulic circuit, which solves the problem that moisture, dust or corrosive substances will enter the cylinder and cause corrosion or damage to the cylinder when one oil port of the unidirectional drive hydraulic rod is open to the atmosphere. (2) When the above scheme is input into the oil inlet through hydraulic oil, the hydraulic oil will first push the spring piston rod downward. At this time, under the action of the spring force, the locking rod will be driven to retract into the valve core body. Subsequently, the pressure of the hydraulic oil will push the valve core assembly downward as a whole. At the same time, a gap will be generated between the outer periphery of the valve core body and the partition ring. The upper and lower parts of the oil inlet will be connected. At this time, the piston rod can move normally into the cylinder body. However, when the device is reset and the hydraulic cylinder needs to be disassembled as a whole, since no pressure is applied at the spring piston rod, one end of the locking rod will abut against the top of the partition ring, causing the valve core body to be unable to move downward. At this time, the lower part of the oil inlet, the hydraulic oil passage and the cavity are in a sealed state, so that the piston rod cannot move. At the same time, with the cooperation of sealing valve one and sealing valve two, it can prevent the operator from accidentally pushing the piston rod to retract and causing the hydraulic oil in the oil inlet to leak. Attached Figure Description

[0016] Figure 1 This is a working diagram of the hydraulic cylinder drive stroke of the present invention; Figure 2 This is a working diagram of the hydraulic cylinder reset stroke of the present invention; Figure 3 This is a frontal perspective view of the hydraulic cylinder of the present invention; Figure 4 This is a schematic diagram of the sealing mechanism of the present invention; Figure 5 This is a front cross-sectional view of the hydraulic cylinder of the present invention; Figure 6 for Figure 5 Enlarged view of point A in the middle; Figure 7 for Figure 6 Enlarged view of point B in the middle; Figure 8 for Figure 5 Enlarged view of point C in the middle; Figure 9 This is a front cross-sectional view of the fuel tank of the present invention.

[0017] In the diagram: 1. Hydraulic cylinder; 11. Cylinder body; 12. Piston rod; 13. Hydraulic oil passage; 14. Oil inlet; 141. Sealing valve one; 142. Separating ring; 15. Oil outlet; 151. Sealing valve two; 152. One-way valve; 153. Micropore; 16. Cavity one; 17. Cavity two; 2. Sealing mechanism; 21. Valve core assembly; 211. Valve core body; 212. Spring piston rod; 213. Spring; 214. Locking rod; 22. Spring telescopic rod; 3. Oil tank; 31. Housing; 32. Annular cover; 33. Elastic diaphragm; 4. Pump body; 5. One-way valve; 6. Collector; 7. Electro-controlled ball valve. Detailed Implementation

[0018] 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. 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.

[0019] like Figures 1 to 9 As shown, the present invention provides a closed-loop hydraulic control system for a pneumatic actuator, including a hydraulic cylinder 1, an oil tank 3, and a pump body 4, and further including: a check valve 5, a manifold 6, and an electrically controlled ball valve 7; wherein, the oil tank 3 is connected to the input end of the pump body 4 through a corresponding pipe, and the output end of the pump body 4 is connected to the manifold 6 in one direction through a corresponding pipe and the check valve 5, and the oil tank 3 can be connected to the manifold 6 through a corresponding pipe and the electrically controlled ball valve 7; The hydraulic cylinder 1 includes a cylinder body 11 and a piston rod 12 movably sleeved inside it. The cylinder body 11 has a hydraulic oil passage 13 and an oil inlet 14 connected to one end of the hydraulic oil passage 13. The cylinder body 11 also has an oil outlet 15. The piston part of the piston rod 12 divides the cylinder body 11 into two spaces. The space where the rod part of the piston rod 12 is located is cavity one 16 and is connected to the hydraulic oil passage 13. The other space is cavity two 17 and is connected to the oil outlet 15. The collector 6 can be connected to the oil inlet 14 through a pipe, and the oil outlet 15 is connected to the oil tank 3 through a pipe. In the initial state, the piston rod 12 has a tendency to move outward due to the elastic force of its own spring part.

[0020] Using the above scheme, by closing the electric ball valve 7 and running the pump body 4, the hydraulic oil in the oil tank 3 is extracted and sent unidirectionally into the oil inlet 14 through the pipeline, check valve 5 and manifold 6. The hydraulic oil enters the first cavity 16 through the hydraulic oil passage 13 to push the piston rod 12 back into the cylinder 11. The hydraulic oil in the second cavity 17 flows back to the oil tank 3 through the oil outlet 15 and the corresponding pipeline. The whole system is in a closed loop state, which avoids external gas or impurities from entering the cylinder and causing corrosion or damage to the cylinder. This scheme adopts a closed hydraulic circuit, which solves the problem that moisture, dust or corrosive substances can enter the cylinder and cause corrosion or damage to the cylinder when one oil port of the unidirectional drive hydraulic rod is open to the atmosphere. During reset, the electrically controlled ball valve 7 is in the open state. At this time, under the elastic force of the spring part on the piston rod 12, the piston rod 12 will be pushed to move outward and reset. The hydraulic oil in the first cavity 16 will flow back to the oil tank 3 for storage through the hydraulic oil passage 13, oil inlet 14, pipeline, manifold 6 and electrically controlled ball valve 7. At the same time, the hydraulic oil in the oil tank 3 will also flow back to the second cavity 17 for storage through the corresponding pipeline and oil outlet 15. Therefore, it should be noted that, due to the presence of the piston rod 12 in cavity 16, the volume of hydraulic oil discharged from cavity 17 is greater than the volume of hydraulic oil input into cavity 16. As a result, when the entire system is working, the oil tank 3 only needs to store a small amount of hydraulic oil to enable the hydraulic cylinder 1 to complete the hydraulic drive stroke.

[0021] like Figures 1-7 As shown, a sealing mechanism 2 for sealing the oil inlet 14 is installed in the oil inlet 14, and a partition ring 142 is fixedly installed in the oil inlet 14. The sealing mechanism 2 includes a valve core assembly 21 that is movably sleeved on the partition ring 142 to divide the cavity of the oil inlet 14 into upper and lower parts. A spring telescopic rod 22 is fixedly connected to the bottom end of the valve core assembly 21, and the bottom end of the spring telescopic rod 22 is installed on the cylinder body 11. In the initial state, the spring telescopic rod 22 can be compressed and stretched. The upper and lower parts of the cavity of the oil inlet 14 can be connected after the valve core assembly 21 moves up or down. The valve core assembly 21 includes a valve core body 211 fixedly installed at the output end of the spring telescopic rod 22. A spring piston rod 212 is movably installed in the valve core body 211. The diameter of the upper part of the spring piston rod 212 is smaller than the diameter of the lower part. The top end of the spring piston rod 212 penetrates through the top of the valve core body 211. Several spring pieces 213 are arranged in a ring array inside the valve core body 211. Each spring piece 213 is fixedly installed with a locking rod 214. One end of the locking rod 214 can abut against the lower part of the spring piston rod 212. At this time, the other end of the locking rod 214 will extend to the outside of the valve core body 211 and abut against the upper surface of the separator ring 142. After the spring piston rod 212 moves down, the spring pieces 213 spring back and reset, so that one end of the locking rod 214 abuts against the upper part of the spring piston rod 212. At this time, the locking rod 214 will retract into the valve core body 211. Both the top and bottom ends of the valve core body 211 are chamfered. The diameter of the top end of the spring piston rod 212 is larger than the diameter of its bottom end, and the top end of the spring piston rod 212 is the piston end. The locking rod 214 is fitted with a sealing ring, and the valve core body 211 is in a sealed state. Using the above scheme, when hydraulic oil is input into the oil inlet 14, the hydraulic oil will first push the spring piston rod 212 downward. At this time, under the action of the spring force of the spring plate 213, it will drive the locking rod 214 to retract into the valve core body 211. Subsequently, the pressure of the hydraulic oil will push the valve core assembly 21 downward as a whole, and at the same time, a gap will be generated between the outer periphery of the valve core body 211 and the separating ring 142, and the upper and lower parts of the oil inlet 14 will be connected. At this time, the piston rod 12 can move normally into the cylinder 11, but when the device re-enters the cylinder... When the hydraulic cylinder 1 needs to be disassembled as a whole after positioning, since no pressure is applied to the spring piston rod 212, one end of the locking rod 214 will abut against the top of the separator ring 142, preventing the valve core body 211 from descending. At this time, the lower part of the oil inlet 14, the hydraulic oil passage 13, and the cavity 16 are in a sealed state, making the piston rod 12 unable to move. At the same time, with the cooperation of the sealing valve 141 and the sealing valve 151, it can prevent the operator from accidentally pushing the piston rod 12 to retract and causing the hydraulic oil in the oil inlet 14 to leak.

[0022] like Figures 6-8 As shown, a sealing valve 141 is provided at the outer end of the oil inlet 14, and a sealing valve 2 151 is provided at the outer end of the oil outlet 15.

[0023] By adopting the above scheme, the setting of sealing valve 141 and sealing valve 2151 allows hydraulic oil to pass through sealing valve 141 and sealing valve 2151 in both directions, while ensuring that sealing valve 141 and sealing valve 2151 respectively block the oil inlet 14 and oil outlet 15. After the hydraulic cylinder 1 is disassembled, hydraulic oil leakage will occur.

[0024] like Figure 8As shown, a one-way valve 152 capable of unidirectional outward conduction is installed inside the oil outlet 15. A micropore 153 is opened in the middle of the one-way valve 152. The one-way valve 152 is located at the inner end of the oil outlet 15, while the sealing valve 151 is located at the outer end of the oil outlet 15. By adopting the above scheme, the piston rod 12 can be quickly retracted into the cylinder 11 when the device is working, and when the device needs to be reset, the flow of hydraulic oil is restricted by the micro-hole 153 to prevent the piston rod 12 from rebounding and resetting too quickly.

[0025] like Figure 1 , Figure 2 and Figure 9 As shown, the fuel tank 3 includes a tank body 31, and an annular cover 32 is installed on the top of the tank body 31. An elastic diaphragm 33 for sealing the top of the tank body 31 is installed on the annular cover 32. By adopting the above solution, the elastic diaphragm 33 can isolate the external gas from the housing 31, while also significantly reducing the impact of pressure changes when the hydraulic oil volume inside the housing 31 changes.

[0026] Working principle and usage process of this invention: When in use, the electric ball valve 7 is closed, the pump body 4 operates to draw hydraulic oil from the oil tank 3 and send it unidirectionally into the oil inlet 14 through the pipeline, check valve 5 and manifold 6. The hydraulic oil will enter the oil outlet 15 through the hydraulic oil passage 13 to push the piston rod 12 back into the cylinder 11. The hydraulic oil in the second cavity 17 will flow back to the oil tank 3 through the oil outlet 15 and the corresponding pipeline to replenish the hydraulic oil input to the oil tank 3. Since there is a piston rod 12 rod body in the first cavity 16, the volume of hydraulic oil discharged from the second cavity 17 will be greater than the volume of hydraulic oil input to the first cavity 16. Thus, when the whole system is working, the oil tank 3 only needs to store a small amount of hydraulic oil to make the hydraulic cylinder 1 complete the hydraulic drive stroke. At the same time, the whole system is in a closed loop state, which prevents external gas or impurities from entering the cylinder and causing corrosion or damage to the cylinder. When the device is reset, the electrically controlled ball valve 7 is in the open state. At this time, under the elastic force of the spring part on the piston rod 12, the piston rod 12 will be pushed to move outward and reset. The hydraulic oil in the first cavity 16 will flow back to the oil tank 3 for storage through the hydraulic oil passage 13, oil inlet 14, pipeline, manifold 6 and electrically controlled ball valve 7. At the same time, the hydraulic oil in the oil tank 3 will also flow back to the second cavity 17 for storage through the corresponding pipeline and oil outlet 15. When hydraulic oil passes through the oil inlet 14, it first pushes the spring piston rod 212 downward. At this time, under the action of the spring plate 213, it will drive the locking rod 214 to retract into the valve core body 211. Subsequently, the pressure of the hydraulic oil will push the valve core assembly 21 downward as a whole. At the same time, a gap will be generated between the outer periphery of the valve core body 211 and the partition ring 142, and the upper and lower parts of the oil inlet 14 will be connected. At this time, the piston rod 12 can move normally into the cylinder body 11. However, when the device is reset and the hydraulic cylinder 1 needs to be disassembled as a whole, since no pressure is applied at the spring piston rod 212, one end of the locking rod 214 will abut against the top of the partition ring 142, causing the valve core body 211 to be unable to move downward. At this time, the lower part of the oil inlet 14, the hydraulic oil passage 13, and the cavity 16 are in a sealed state, making the piston rod 12 unable to move. At the same time, with the cooperation of the sealing valve 141 and the sealing valve 151, the hydraulic oil leakage in the oil inlet 14 can be avoided.

[0027] It should be noted that, in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such process, method, article, or apparatus.

[0028] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A closed hydraulic control system for a pneumatic actuator, comprising a hydraulic cylinder (1), an oil tank (3) and a pump body (4), characterized in that, It also includes: a check valve (5), a manifold (6), and an electrically controlled ball valve (7); Among them, the oil tank (3) is connected to the input end of the pump body (4) through the corresponding pipe, and the output end of the pump body (4) is connected to the collector (6) in one direction through the corresponding pipe and the one-way valve (5). The oil tank (3) can be connected to the collector (6) through the corresponding pipe and the electric ball valve (7). The hydraulic cylinder (1) includes a cylinder body (11) and a piston rod (12) movably sleeved inside it. The cylinder body (11) has a hydraulic oil passage (13) and an oil inlet (14) connected to one end of the hydraulic oil passage (13). The cylinder body (11) also has an oil outlet (15). The piston part of the piston rod (12) divides the cylinder body (11) into two spaces. The space where the rod part of the piston rod (12) is located is cavity one (16) and is connected to the hydraulic oil passage (13). The other part of the space is cavity two (17) and is connected to the oil outlet (15). The collector (6) can be connected to the oil inlet (14) through a pipe, and the oil outlet (15) can be connected to the oil tank (3) through a pipe; In the initial state, the piston rod (12) tends to move outward due to the elastic force of its own spring.

2. Closed hydraulic control system for a pneumatic actuator according to claim 1, characterized in that: The oil inlet (14) is equipped with a sealing mechanism (2) for sealing the oil inlet (14).

3. The closed hydraulic control system for a pneumatic actuator according to claim 2, characterized in that: A separator ring (142) is fixedly installed in the oil inlet (14); The sealing mechanism (2) includes a valve core assembly (21) that is movably sleeved on the separator ring (142) to divide the oil inlet (14) cavity into two parts, an upper and an lower part. The bottom end of the valve core assembly (21) is fixedly connected to a spring telescopic rod (22), and the bottom end of the spring telescopic rod (22) is installed on the cylinder body (11). In the initial state, the spring telescopic rod (22) can be compressed and contracted and stretched. The valve core assembly (21) can make the upper and lower parts of the oil inlet (14) cavity open when it moves up or down.

4. The closed hydraulic control system for a pneumatic actuator according to claim 3, characterized in that: The valve core assembly (21) includes a valve core body (211) fixedly installed at the output end of the spring telescopic rod (22). A spring piston rod (212) is movably installed in the valve core body (211). The diameter of the upper part of the spring piston rod (212) is smaller than the diameter of the lower part. The top end of the spring piston rod (212) penetrates the top of the valve core body (211). A number of spring pieces (213) are arranged in a ring array inside the valve core body (211). A locking rod (214) is fixedly installed on each spring piece (213). One end of the locking rod (214) can abut against the lower part of the spring piston rod (212). At this time, the other end of the locking rod (214) will extend to the outside of the valve core body (211) and abut against the upper surface of the separator ring (142). After the spring piston rod (212) moves downward, the spring piece (213) springs back to its original position, which allows one end of the locking rod (214) to abut against the upper part of the spring piston rod (212), and at this time the locking rod (214) will retract into the valve core body (211).

5. The closed hydraulic control system for a pneumatic actuator according to claim 4, characterized in that: The top and bottom ends of the valve core body (211) are both chamfered.

6. The closed hydraulic control system for a pneumatic actuator according to claim 5, characterized in that: The diameter of the top end of the spring piston rod (212) is larger than the diameter of its lower part, and the top end of the spring piston rod (212) is the piston end; The locking rod (214) is fitted with a sealing ring, and the valve core body (211) is in a sealed state.

7. The closed hydraulic control system for a pneumatic actuator according to claim 3, wherein: The outer end of the oil inlet (14) is provided with a sealing valve one (141), and the outer end of the oil outlet (15) is provided with a sealing valve two (151).

8. The closed hydraulic control system for a pneumatic actuator of claim 1, wherein: The oil outlet (15) is equipped with a one-way valve (152) that can conduct one-way outward, and the one-way valve (152) has a micropore (153) in the middle. The one-way valve (152) is located at the inner end of the oil outlet (15), while the sealing valve (151) is located at the outer end of the oil outlet (15).

9. The closed hydraulic control system for a pneumatic actuator of claim 1, wherein: The oil tank (3) includes a tank body (31), and an annular cover (32) is installed on the top of the tank body (31). An elastic diaphragm (33) for sealing the top of the tank body (31) is installed on the annular cover (32).

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