A positive and negative pressure generating and switching system and method

Abstract

This invention belongs to the field of pneumatic equipment technology, and particularly relates to a positive and negative pressure generation and switching system. It includes a cylinder with an air inlet at each end, a piston rod assembly slidably installed inside the cylinder with one end extending out of the cylinder, a drive mechanism connected to the piston rod assembly's extending end and used to drive the piston rod assembly to reciprocate along the inner wall of the cylinder, two switching components respectively connected to the two air inlets, an external pipeline connected to both switching components and used to connect to the object to be pressure regulated, and a control component signal-connected to the drive mechanism and the switching components. The control component controls the two switching components to alternately input gas from the atmosphere into the external pipeline to form positive pressure, or alternately draw gas from the external pipeline into the atmosphere to form negative pressure, following the reciprocating stroke of the piston rod assembly. This system achieves positive and negative pressure generation and switching without the need for an external air source, facilitating the integrated design of a pneumatic pressure control system.

Description

Technical Field

[0001] This invention belongs to the field of pneumatic equipment technology, and particularly relates to a positive and negative pressure generation and switching system and method. Background Technology

[0002] In pneumatic soft robots, the air pressure control system is fundamental to achieving robot motion control. To realize movements such as extension, bending, and contraction of the soft robot, the controller needs to provide both positive and negative air pressure simultaneously and achieve real-time control. Existing commonly used positive and negative air pressure controllers rely on air compressors and vacuum pumps as air source inputs, as well as proportional valves and other devices for air pressure control. These are expensive, bulky, and not conducive to system integration.

[0003] A Chinese patent discloses a positive and negative air pressure switching system. This system includes a first air port, a second air port, and a third air port, each connected to the first air port. The first air port connects to an external pneumatic device, while the second and third air ports connect to an external positive pressure air source and an external negative pressure air source, respectively. A first solenoid valve controls the opening and closing of the first and second air ports, and a second solenoid valve controls the opening and closing of the first and third air ports. In actual use, the solenoid valves and the air source devices work together to achieve rapid switching between the positive and negative pressure air source devices and the pneumatic device, allowing the pneumatic device to quickly switch between positive and negative pressure. However, this device can only switch between positive and negative air pressure and still requires an air compressor and a vacuum pump for air input, thus not solving the air supply problem. Summary of the Invention

[0004] The purpose of this invention is to provide a positive and negative pressure generation and switching system and method that can generate and switch positive and negative pressure without the need for an external air source, which facilitates the integrated design of the air pressure control system and enables the miniaturization and economical design of the air pressure controller.

[0005] This invention is implemented as follows: a positive and negative pressure generation and switching system, comprising: a cylinder with an air inlet at each end; a piston rod assembly slidably installed inside the cylinder with one end extending out of the cylinder; a drive mechanism connected to the end of the piston rod assembly and used to drive the piston rod assembly to reciprocate along the inner wall of the cylinder; two switching components respectively connected to the two air inlets; an external pipeline connected to both switching components and used to connect to the object to be pressure regulated; and a control component signal-connected to the drive mechanism and the switching components. The control component is used to control the two switching components to alternately input gas from the atmosphere into the external pipeline to form positive pressure, or alternately draw gas from the external pipeline into the atmosphere to form negative pressure, following the reciprocating stroke of the piston rod assembly.

[0006] This invention discloses a positive and negative pressure generation and switching system. By setting a drive mechanism, it facilitates the reciprocating motion of a piston rod assembly along a cylinder, driving gas to enter or exit the cylinder through air inlets at both ends. During the reciprocating motion of the piston rod assembly, two switching components, under the action of a control component, can alternately deliver gas from the atmosphere to the external pipeline, thereby achieving continuous positive pressure output. Alternatively, the two switching components can alternately draw gas from the external pipeline into the atmosphere, thereby achieving continuous negative pressure output. Therefore, positive and negative pressure generation and switching can be achieved without an external air source, facilitating the integrated design of the air pressure control system and enabling the miniaturization and economical design of the air pressure controller.

[0007] Preferably, the switching component includes: a Y-shaped connector with one end connected to the air inlet, two one-way valves respectively connected to two branches of the Y-shaped connector and facing opposite directions, and a reversing valve connected to the end of the two one-way valves away from the Y-shaped connector, and the external pipeline is connected to both reversing valves.

[0008] Preferably, the reversing valve is a two-position four-way valve, and the valve body is sequentially provided with a first port, a second port connected to the input end of one of the one-way valves, a third port connected to the output end of the other one-way valve, and a fourth port open to the atmosphere. The external pipeline is simultaneously connected to the first ports of the two reversing valves at the same working position. The reversing valve is used to control the first port and the third port to be connected, and the second port and the fourth port to be connected to generate positive pressure in the external pipeline, or to control the first port and the second port to be connected, and the third port and the fourth port to be connected to generate negative pressure in the external pipeline.

[0009] Preferably, a sealing plug is also fixedly installed at the position where the air inlet connects to the Y-shaped connector.

[0010] Preferably, the external pipeline includes: branch pipes respectively connected to the first ports of the two reversing valves, and a confluence pipe connected to the end of the two branch pipes away from the reversing valves.

[0011] Preferably, the piston rod assembly includes: a piston slidably mounted inside the cylinder, and a piston rod fixedly connected to one side of the piston and extending out from one end of the cylinder, wherein the drive mechanism is fixedly connected to the piston rod.

[0012] Preferably, the drive mechanism includes: a support platform, a drive motor disposed inside the support platform, a crank connecting rod located above the support platform and connected to the output end of the drive motor, and a push rod slidably mounted on the top of the support platform and connected at one end to the crank connecting rod, wherein the end of the push rod away from the crank connecting rod is fixedly connected to the piston rod.

[0013] Preferably, the control component includes: a controller whose signals are connected to the drive motor and the reversing valve, and a sensor connected to the external pipeline and whose signals are connected to the controller.

[0014] This invention also provides a method for generating and switching positive and negative pressure, specifically including:

[0015] Step S1: Connect the external pipeline to the object to be pressure regulated, and input the target air pressure value Pt to the controller;

[0016] Step S2: The controller determines whether the current target air pressure value Pt is positive. If it is, it directly executes step S3. If not, it controls the two reversing valves to switch the air path at the same time, and then executes step S3.

[0017] Step S3: The controller controls the drive motor to operate, which drives the piston rod assembly to move and continuously generate air pressure through the external pipeline; during this process, the sensor detects the current air pressure value Pc of the external pipeline in real time and transmits the detection result to the controller.

[0018] Step S4: The controller compares the current air pressure value Pc with the target air pressure value Pt. If Pc≥Pt, the controller will cut off the power to the drive motor and exit the process. Otherwise, it will return to step S3 until Pc≥Pt.

[0019] Preferably, in step S3, the controller controls the gas output speed or intake speed by adjusting the power of the drive motor.

[0020] Compared with the prior art, the beneficial effects of the present invention are as follows: By setting a driving mechanism, it is easy to drive the piston rod assembly to reciprocate along the cylinder, driving gas to enter or exit the cylinder through the air inlets at both ends. During the reciprocating motion of the piston rod assembly, the two switching components can, under the action of the control component, alternately deliver gas from the atmosphere to the external pipeline to achieve continuous positive pressure output, or the two switching components can alternately draw gas from the external pipeline to the atmosphere to achieve continuous negative pressure output. By setting a switching component consisting of two one-way valves and a reversing valve, the characteristics of the one-way valve can be used to make the gas output no longer limited to the cylinder capacity. By using the reversing valve to switch the gas path, positive and negative pressure can be generated and switched without an external gas source, which facilitates the integrated design of the pneumatic control system, thereby realizing the miniaturization and economical design of the pneumatic controller. Attached Figure Description

[0021] Figure 1 A schematic diagram of a positive and negative pressure generation and switching system provided by the present invention;

[0022] Figure 2 This is a schematic diagram of a positive and negative pressure generation and switching system provided by the present invention during the positive pressure propulsion stroke;

[0023] Figure 3 A schematic diagram of a positive and negative pressure generation and switching system provided by the present invention during the positive pressure return stroke;

[0024] Figure 4 This is a schematic diagram of a positive and negative pressure generation and switching system provided by the present invention during the negative pressure propulsion stroke;

[0025] Figure 5 This invention provides a schematic diagram of a positive and negative pressure generation and switching system during the negative pressure return stroke.

[0026] Figure 6 A flowchart of a positive and negative pressure generation and switching method provided by the present invention.

[0027] In the attached diagram: 1-Cylinder, 2-Piston rod assembly, 21-Piston, 22-Piston rod, 3-Drive mechanism, 31-Support platform, 32-Drive motor, 33-Crank connecting rod, 34-Push rod, 4-Switching assembly, 41-Y-connector, 42-One-way valve, 43-Directional valve, 431-First port, 432-Second port, 433-Third port, 434-Fourth port, 5-Control assembly, 51-Controller, 52-Sensor, 6-External pipeline, 61-Branch pipe, 62-Combination pipe, 7-Sealing plug. Detailed Implementation

[0028] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the specific technical solutions of this application will be further described in detail below with reference to the accompanying drawings of the embodiments of this application. The following embodiments are used to illustrate this application, but are not intended to limit the scope of this application.

[0029] In the embodiments of this application, the terms "first" and "second" 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. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of the embodiments of this application, unless otherwise stated, "multiple" means two or more.

[0030] Furthermore, in the embodiments of this application, directional terms such as "upper," "lower," "left," and "right" are defined relative to the positions in which the components are schematically placed in the accompanying drawings. It should be understood that these directional terms are relative concepts, used for relative description and clarification, and can change accordingly depending on the position of the components in the accompanying drawings.

[0031] In the embodiments of this application, unless otherwise explicitly specified and limited, the term "connection" should be interpreted broadly. For example, "connection" can be a fixed connection, a detachable connection, or an integral part; it can be a direct connection or an indirect connection through an intermediate medium.

[0032] In embodiments of this application, 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 a process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes that element.

[0033] In the embodiments of this application, the terms "exemplary" or "for example" are used to indicate that something is an example, illustration, or description. Any embodiment or design that is described as "exemplary" or "for example" in the embodiments of this application should not be construed as being more preferred or advantageous than other embodiments or design. Specifically, the use of the terms "exemplary" or "for example" is intended to present the relevant concepts in a specific manner.

[0034] Example 1

[0035] like Figure 1 The diagram shows a structural diagram of a positive and negative pressure generation and switching system provided by the present invention, comprising: a cylinder 1 with an air inlet at each end; a piston rod assembly 2 slidably installed inside the cylinder 1 with one end extending out of the cylinder 1; a drive mechanism 3 connected to the end of the piston rod assembly 2 and used to drive the piston rod assembly 2 to reciprocate along the inner wall of the cylinder 1; two switching components 4 respectively connected to the two air inlets; an external pipeline 6 connected to the two switching components 4 and used to connect to the object to be pressure regulated; and a control component 5 signal-connected to the drive mechanism 3 and the switching components 4. The control component 5 is used to control the two switching components 4 to alternately input gas from the atmosphere into the external pipeline 6 to form positive pressure, or alternately draw gas from the external pipeline 6 into the atmosphere to form negative pressure, following the reciprocating stroke of the piston rod assembly 2.

[0036] In practical applications, this embodiment uses a drive mechanism 3 to facilitate the reciprocating motion of the piston rod assembly 2 along the cylinder 1, allowing gas to enter or exit the cylinder 1 through the air inlets at both ends. During the reciprocating motion of the piston rod assembly 2, the two switching components 4, under the control of the control component 5, can alternately deliver gas from the atmosphere to the external pipeline 6, thereby achieving continuous positive pressure output. Alternatively, the two switching components 4 can alternately draw gas from the external pipeline 6 into the atmosphere, thereby achieving continuous negative pressure output. Therefore, positive and negative pressure generation and switching can be achieved without an external air source, facilitating the integrated design of the air pressure control system and enabling the miniaturization and economical design of the air pressure controller.

[0037] Specifically, the switching component 4 includes: a Y-shaped connector 41 with one end connected to the air inlet, two one-way valves 42 connected to two branches of the Y-shaped connector 41 and facing opposite directions, and a reversing valve 43 connected to the two one-way valves 42 at the ends away from the Y-shaped connector 41. The external pipeline 6 is connected to both reversing valves 43.

[0038] Furthermore, the reversing valve 43 is a two-position four-way valve, and the valve body is sequentially provided with a first port 431, a second port 432 connected to the input end of one of the one-way valves 42, a third port 433 connected to the output end of the other one-way valve 42, and a fourth port 434 connected to the atmosphere. The external pipeline 6 is simultaneously connected to the first port 431 of the two reversing valves 43 at the same working position. The reversing valve 43 is used to control the first port 431 and the third port 433 to communicate, and the second port 432 and the fourth port 434 to communicate to generate positive pressure in the external pipeline 6, or to control the first port 431 and the second port 432 to communicate, and the third port 433 and the fourth port 434 to communicate to generate negative pressure in the external pipeline 6.

[0039] It can be seen that after connecting the Y-shaped connector 41 to the air inlet, the two one-way valves 42 with different branches and opposite directions are used to block and allow the gas to pass through.

[0040] When positive pressure is required in the external pipeline 6, both directional valves 43 control the first port 431 and the third port 433 to connect, and the second port 432 and the fourth port 434 to connect, such as Figure 2 As shown, during the piston rod assembly 2's pushing stroke, atmospheric gas is input through the fourth port 434 of the reversing valve 43 located on the side of cylinder 1's volume expansion. The gas flows through the second port 432, passes through the input end of the one-way valve 42 on that side, and is then injected into the cylinder 1. On the side of cylinder 1 where the volume decreases, gas flows out from the air inlet, passes through the input end of the one-way valve 42 on that side, and then flows through the third port 433 and the first port 431 before being injected into the external wiring pipe 6. This allows gas to flow from the atmosphere into the external wiring pipe 6, generating positive pressure.

[0041] During the return stroke of piston rod assembly 2, such as Figure 3 As shown, similarly, positive pressure can be generated in both the pushing and returning strokes of piston rod assembly 2, thus achieving continuous positive pressure generation without the need for an external air source or air pump.

[0042] When negative pressure needs to be generated in external pipeline 6, such as Figure 4 As shown, both reversing valves 43 control the connection between the first port 431 and the second port 432, and between the third port 433 and the fourth port 434. During the piston rod assembly 2's push-in stroke, gas from the external pipeline 6 is input through the first port 431 of the reversing valve 43 located on the side of cylinder 1's volume expansion. The gas then flows through the second port 432, passes through the input end of the one-way valve 42 on that side, and is injected into the cylinder 1. On the side of cylinder 1's volume reduction, gas flows out from the air inlet, passes through the input end of the one-way valve 42 on that side, and then flows through the third port 433 and the fourth port 434 before being injected into the atmosphere. This allows gas to flow from the external pipeline 6 into the atmosphere, creating negative pressure.

[0043] During the return stroke of piston rod assembly 2, such as Figure 5 As shown, similarly, negative pressure can be generated in both the pushing and returning strokes of piston rod assembly 2, thus achieving continuous generation of negative pressure without the need for an external air source or air pump.

[0044] It should be noted that by setting up a switching component 4 consisting of two one-way valves 42 and a reversing valve 43, the gas output is no longer limited to the capacity of cylinder 1 by utilizing the characteristics of the one-way valve 42. The positive and negative air pressures are switched by using the reversing valve 43, which solves the problems of high price, large size and difficulty in integration of traditional air pressure control systems. It has strong practicality and economy and is convenient for use in different scenarios.

[0045] Example 2

[0046] like Figure 1 As shown, based on Embodiment 1, the external pipeline 6 includes: branch pipes 61 that are respectively connected to the first ports 431 of the two reversing valves 43, and a confluence pipe 62 that is connected to the end of the two branch pipes 61 away from the reversing valves 43.

[0047] In practical application, this embodiment utilizes the external pipeline 6, which can be connected to the first port 431 of the reversing valve 43 through two branch pipes 61, and then overlapped through the confluence pipe 62. The piston rod assembly 2 can generate positive and negative pressure in both the forward and reverse strokes, thus making the pressure generation process continuous.

[0048] Furthermore, a sealing plug 7 is also fixedly installed at the position where the air inlet connects to the Y-shaped connector 41.

[0049] It can be seen that by using the sealing plug 7, the sealing performance at the connection between the Y-shaped connector 41 and the air inlet can be improved, ensuring the smooth generation and switching of positive and negative pressure.

[0050] Furthermore, such as Figure 2 As shown, the piston rod assembly 2 includes: a piston 21 slidably mounted inside the cylinder 1, and a piston rod 22 fixedly connected to one side of the piston 21 and extending out from one end of the cylinder 1. The drive mechanism 3 is fixedly connected to the piston rod 22.

[0051] It can be seen that by the piston 21 sliding back and forth inside the cylinder 1, the gas flow process can be easily driven. In conjunction with the drive mechanism 3, positive and negative pressure can be generated without the need for an external air source, which reduces the cost and size of the pneumatic controller 51.

[0052] In one embodiment, the drive mechanism 3 includes: a support platform 31, a drive motor 32 disposed inside the support platform 31, a crank connecting rod 33 located above the support platform 31 and connected to the output end of the drive motor 32, and a push rod 34 slidably mounted on the top of the support platform 31 and connected at one end to the crank connecting rod 33, wherein the end of the push rod 34 away from the crank connecting rod 33 is fixedly connected to the piston rod 22.

[0053] It can be understood that the drive motor 32 drives the crank connecting rod 33 to reciprocate, which in turn drives the piston rod 22 to move, thereby causing the piston 21 to slide back and forth along the cylinder 1.

[0054] It should be noted that, in this embodiment, in addition to the combination of drive motor 32 and crank connecting rod 33 as in this embodiment, the drive mechanism 3 can also be a combination of drive motor 32 and electric push rod, as long as it can drive piston rod assembly 2 to reciprocate along cylinder 1. This embodiment does not make specific limitations here.

[0055] For example, the control component 5 includes: a controller 51 whose signal is connected to the drive motor 32 and the reversing valve 43, and a sensor 52 connected to the external pipeline 6 and whose signal is connected to the controller 51.

[0056] It can be seen that the controller 51 facilitates the power adjustment of the drive motor 32, thereby realizing the magnitude of positive and negative pressure generation. The sensor 52 can measure the pressure value of the external pipeline 6 so that the controller 51 can control the device to achieve the target pressure value. In addition, the reversing valve 43 can switch the air path under the action of the controller 51 to realize the switching of positive and negative pressure, so as to generate negative or positive pressure according to actual needs.

[0057] For example, the drive motor 32 can be a DC motor. To prevent overshoot during air pressure supply, a PID controller 51 can be used to adjust the voltage of the DC motor in real time to ensure that the motor outputs full power when the air is first supplied, quickly reaching the vicinity of the target air pressure value. After reaching the vicinity of the target value, the motor power is gradually reduced to reduce the movement speed of the piston rod assembly 2, and finally stops smoothly at the target air pressure value.

[0058] Example 3

[0059] This embodiment is an example of a method for generating and switching positive and negative pressure, such as... Figure 6 As shown, it specifically includes:

[0060] Step S1: Connect the external pipeline 6 to the object to be pressure regulated, and input the target air pressure value Pt into the controller 51;

[0061] Step S2: Controller 51 determines whether the current target air pressure value Pt is positive. If it is, it directly executes step 3. If not, it controls the two reversing valves 43 to switch the air path at the same time, and then executes step S3.

[0062] Step S3: The controller 51 controls the drive motor 32 to operate, which drives the piston rod assembly 2 to move and continuously generate air pressure in the external pipeline 6; during this process, the sensor 52 detects the current air pressure value Pc of the external pipeline 6 in real time and transmits the detection result to the controller 51.

[0063] Step S4: The controller 51 compares the current air pressure value Pc with the target air pressure value Pt. When Pc≥Pt, the controller controls the drive motor 32 to cut off power and exit the process. Otherwise, it returns to step S3 until Pc≥Pt.

[0064] Specifically, the controller 51 inputs the target pressure value required by the external pipeline 6, and then judges the target pressure value to determine whether to control the reversing valve 43 to switch the air path first; the drive motor 32 can drive the piston rod assembly 2 under the signal of the controller 51; when the preset pressure is reached, the drive motor 32 is de-energized to maintain the pressure; it can also switch according to the input target air pressure value using the reversing valve 43 to generate different target pressures, so as to achieve the generation and switching of target pressure without the need for an external air source.

[0065] In one embodiment, in step S3, the controller 51 controls the output speed or intake speed of the gas by adjusting the power of the drive motor 32.

[0066] It can be seen that by adjusting the power of the drive motor 32 through the controller 51, the output speed and intake speed of the gas can be adjusted, which is more convenient and faster.

[0067] The above embodiments of the present invention provide a positive and negative pressure generation and switching system. By setting a drive mechanism 3, the piston rod assembly 2 is driven to reciprocate along the cylinder 1, driving gas to enter or exit the cylinder 1 through the air inlets at both ends. During the reciprocating motion of the piston rod assembly 2, the two switching components 4 can, under the action of the control component 5, alternately deliver gas from the atmosphere to the external pipeline 6, thereby achieving continuous positive pressure output, or the two switching components 4 can alternately draw gas from the external pipeline 6 to the atmosphere, thereby achieving continuous negative pressure output. By setting a switching component 4 consisting of two one-way valves 42 and a reversing valve 43, the gas output is no longer limited to the capacity of the cylinder 1 by utilizing the characteristics of the one-way valve 42, and the gas path is switched by the reversing valve 43. Therefore, positive and negative pressure generation and switching can be achieved without an external gas source, which facilitates the integrated design of the air pressure control system, thereby realizing the miniaturization and economical design of the air pressure controller.

[0068] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A positive and negative pressure generating and switching system, characterized by, include: A cylinder (1) with an air inlet at each end, a piston rod assembly (2) slidably installed inside the cylinder (1) and with one end protruding from the cylinder (1), a drive mechanism (3) connected to the protruding end of the piston rod assembly (2) and used to drive the piston rod assembly (2) to reciprocate along the inner wall of the cylinder (1), two switching components (4) respectively connected to the two air inlets, an external pipeline (6) connected to the two switching components (4) and used to connect to the object to be pressure regulated, and a control component (5) connected to the drive mechanism (3) and the switching components (4) by signal. The control component (5) is used to control the two switching components (4) to alternately input gas from the atmosphere to the external pipeline (6) to form positive pressure, or alternately draw gas from the external pipeline (6) into the atmosphere to form negative pressure, following the reciprocating stroke of the piston rod assembly (2). The switching assembly (4) includes: a Y-shaped connector (41) with one end connected to the air inlet, two one-way valves (42) respectively connected to two branches of the Y-shaped connector (41) and facing opposite directions, and a reversing valve (43) connected to the end of the two one-way valves (42) away from the Y-shaped connector (41). The external pipeline (6) is connected to both reversing valves (43). The piston rod assembly (2) includes: a piston (21) slidably mounted inside the cylinder (1) and a piston rod (22) fixedly connected to one side of the piston (21) and extending out from one end of the cylinder (1), and the drive mechanism (3) is fixedly connected to the piston rod (22).

2. The positive and negative pressure generating and switching system according to claim 1, characterized by, The reversing valve (43) is a two-position four-way valve, and the valve body is provided with a first port (431), a second port (432) connected to the input end of one of the check valves (42), a third port (433) connected to the output end of the other check valve (42), and a fourth port (434) connected to the atmosphere. The external pipeline (6) is connected to the first port (431) of the two reversing valves (43) at the same working position. The reversing valve (43) is used to control the first port (431) and the third port (433) to communicate, the second port (432) and the fourth port (434) to communicate to generate positive pressure in the external pipeline (6), or to control the first port (431) and the second port (432) to communicate, the third port (433) and the fourth port (434) to communicate to generate negative pressure in the external pipeline (6).

3. The positive and negative pressure generation and switching system according to claim 2, characterized in that, A sealing plug (7) is also fixedly installed at the connection between the air inlet and the Y-shaped connector (41).

4. The positive and negative pressure generation and switching system according to claim 2, characterized in that, The external pipeline (6) includes: branch pipes (61) connected to the first ports (431) of the two reversing valves (43) respectively, and a confluence pipe (62) connected to the end of the two branch pipes (61) away from the reversing valves (43).

5. The positive and negative pressure generation and switching system according to claim 1, characterized in that, The drive mechanism (3) includes: a support platform (31), a drive motor (32) located inside the support platform (31), a crank connecting rod (33) located above the support platform (31) and connected to the output end of the drive motor (32), and a push rod (34) slidably mounted on the top of the support platform (31) and connected at one end to the crank connecting rod (33). The end of the push rod (34) away from the crank connecting rod (33) is fixedly connected to the piston rod (22).

6. The positive and negative pressure generation and switching system according to claim 5, characterized in that, The control component (5) includes: a controller (51) whose signal is connected to the drive motor (32) and the reversing valve (43), and a sensor (52) whose signal is connected to the external pipeline (6) and the controller (51).

7. A method for generating and switching positive and negative pressure applied to the positive and negative pressure generation and switching system according to any one of claims 1-6, characterized in that, include: Step S1: Connect the external pipeline (6) to the object to be pressure regulated, and input the target air pressure value Pt to the controller (51); Step S2: The controller (51) determines whether the current target air pressure value Pt is positive. If it is, it directly executes step S3. If not, it controls the two reversing valves (43) to switch the air path at the same time, and then executes step S3. Step S3: The controller (51) controls the drive motor (32) to operate, driving the piston rod assembly (2) to move and continuously generate air pressure to the external pipeline (6); during this process, the sensor (52) detects the current air pressure value Pc of the external pipeline (6) in real time and transmits the detection result to the controller (51). Step S4: The controller (51) compares the current air pressure value Pc with the target air pressure value Pt. When Pc≥Pt, the controller controls the drive motor (32) to power off and exits the process. Otherwise, it returns to step S3 until Pc≥Pt.

8. The method for generating and switching positive and negative pressure according to claim 7, characterized in that, In step S3, the controller (51) controls the output speed or intake speed of the gas by adjusting the power of the drive motor (32).

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