Double-suction double-discharge reciprocating injection pump

Abstract

The utility model discloses a double-suction double-discharge reciprocating injection pump which comprises a pump body, a liquid inlet pipe and a liquid outlet pipe, two pistons are arranged in an inner cavity of the pump body at intervals in the length direction, the two pistons are movably assembled with the inner cavity of the pump body in a sealing mode, and the inner cavity of the pump body is divided into a first closed cavity, a sterilization air cavity and a second closed cavity by the pistons, a linkage rod located in the sterilization air cavity is arranged between the two pistons; one end of the pump body is provided with a first interface and a second interface which are respectively communicated with the first closed cavity, the other end of the pump body is provided with a third interface and a fourth interface which are respectively communicated with the second closed cavity, the first interface and the third interface are both communicated with the liquid inlet pipe, and the second interface and the fourth interface are both communicated with the liquid outlet pipe; one-way valves are arranged in the first connector, the second connector, the third connector and the fourth connector respectively. The liquid balance device can solve the problem of liquid balance of continuous blood purification equipment in a vibration impact environment of a moving occasion, simplifies the principle, and improves the reliability.

Description

Technical Field

[0001] This utility model relates to the field of medical device technology, specifically to a double-suction double-discharge reciprocating injection pump. Background Technology

[0002] The accuracy of fluid balance in emergency medical equipment such as continuous blood purification devices is crucial. The market primarily uses the metering method and the balance chamber method.

[0003] The metering method requires the external liquid pump to deliver the liquid, and uses high-precision liquid metering sensors (such as load cells and volumetric sensors) to form a feedback closed-loop control to precisely control the flow rate between the delivery pump and the waste pump. This approach heavily relies on the accuracy of the liquid metering sensors. When there are environmental factors such as vibration and shock, the accuracy of the liquid metering sensors cannot be guaranteed, so the equipment cannot be used in mobile applications.

[0004] The basic principle of the balanced cavity method is as follows: Figure 1 As shown, two linked pistons 2 are placed in the same cavity, with a fixed partition between them, forming four closed cavities: cavity Y1, cavity Y2, cavity Z1, and cavity Z2. Each cavity has the same cross-sectional area, so the volume change of the four cavities is the same when pistons 2 move. When liquid is pumped into cavity Y1 by an external pump, waste liquid is discharged from the body in cavity Z1, liquid is input into the body in cavity Y2, and liquid is discharged into the waste liquid bag in cavity Z2. When liquid is pumped into cavity Y2, waste liquid is discharged from the body in cavity Z2, liquid is input into the body in cavity Y1, and liquid is discharged into the waste liquid bag in cavity Z1. The direction of liquid flow is controlled by the external pump and an electromagnetic on / off valve. The main disadvantage of this method is the complex structure of the balancing cavity, the complex liquid circuit due to the need for an external pump and an electromagnetic on / off valve, and low reliability. Utility Model Content

[0005] The technical problem to be solved by this utility model is to provide a double-suction double-discharge reciprocating syringe pump to solve the problem of liquid balance in continuous blood purification equipment under vibration and shock environment in mobile settings, while simplifying the principle and improving reliability.

[0006] To solve the above-mentioned technical problems, the technical solution adopted by this utility model is as follows.

[0007] A double-suction, double-discharge reciprocating syringe pump includes a pump body, an inlet pipe, and an outlet pipe. Two pistons are spaced along the length of the pump body's inner cavity, forming a first sealed chamber, a sterilization gas chamber, and a second sealed chamber arranged sequentially. A linkage rod located in the sterilization gas chamber is fixedly connected between the two pistons to achieve linkage between them. One end of the pump body has a first interface and a second interface respectively communicating with the first sealed chamber, and the other end has a third interface and a fourth interface respectively communicating with the second sealed chamber. The first and third interfaces are both connected to the inlet pipe, and the second and fourth interfaces are both connected to the outlet pipe. The first interface has an A-side inlet check valve, the second interface has an A-side outlet check valve, the third interface has a B-side inlet check valve, and the fourth interface has a B-side outlet check valve.

[0008] Preferably, the sterilization air chamber is provided with a mounting seat fixedly sleeved in the middle of the linkage rod and perpendicular to the linkage rod. The mounting seat is connected to a connecting rod that passes through the pump body and is used to drive the piston linkage through a slot structure.

[0009] Preferably, the outer end of the connecting rod away from the mounting base is connected to an electric cylinder for driving the connecting rod to move in order to drive the piston in conjunction with the connecting rod.

[0010] Preferably, the pump body has an opening for avoiding the connecting rod during the movement of the connecting rod; the pump body is provided with flexible tubes symmetrically arranged on both sides of the mounting base and connected to the mounting base and the inner cavity of the pump body respectively to cover the opening to ensure the airtightness of the sterilization air chamber and to divide the sterilization air chamber into a first sterilization air chamber and a second sterilization air chamber.

[0011] Preferably, the linkage rod is provided with an air passage for connecting the first sterilization air chamber and the second sterilization air chamber to ensure the air pressure balance between the first sterilization air chamber and the second sterilization air chamber.

[0012] The technological advancements achieved by this utility model are as follows, due to the adoption of the above technical solutions.

[0013] This invention, through its pump body, piston, linkage rod, connecting rod, and one-way valve, not only achieves liquid balance control without relying on high-precision sensors such as liquid flow meters, but also exhibits good tolerance to vibration and shock environments, ensuring high-precision liquid balance control even under vibration and shock conditions. This makes it suitable for mobile applications, enabling continuous blood purification equipment to be used in mobile emergency settings such as ambulances, significantly improving the treatment effect for some critically ill patients. Furthermore, it integrates liquid balance control and the pump into one unit, employing a one-way valve for flow distribution. Compared to the traditional balanced chamber structure, this reduces the number of components, simplifies the structure, and provides higher reliability. Attached Figure Description

[0014] Figure 1 This is a basic schematic diagram of the existing balanced cavity method;

[0015] Figure 2 This is a simplified structural diagram of the present invention;

[0016] Figure 3 This is a schematic diagram of the physical structure of this utility model;

[0017] Figure 4 For the present utility model Figure 3 A side sectional view of the actual object.

[0018] The components are: 1. Pump body, 2. Piston, 3. Linkage rod, 4. Air passage, 5. Mounting base, 6. Connecting rod, 7. Flexible tube, 8. Sterilization air chamber, 81. First sterilization air chamber, 82. Second sterilization air chamber, 9. Inlet pipe, 10. Outlet pipe, A1. First sealed chamber, B1. Second sealed chamber, A1-F1. A-side inlet check valve, A1-F2. A-side outlet check valve, B1-F1. B-side inlet check valve, B1-F2. B-side outlet check valve, Y1. First cavity, Y2. Second cavity, Z1. Third cavity, Z2. Fourth cavity. Detailed Implementation

[0019] The present invention will now be described in further detail with reference to the accompanying drawings and specific embodiments.

[0020] A double-suction, double-discharge reciprocating syringe pump, combined with Figures 2 to 4 As shown, the system includes a pump body 1, an inlet pipe 9, and an outlet pipe 10. A piston 2 is housed within the inner cavity of the pump body 1, forming a structure similar to a syringe. The inlet pipe 9 and the outlet pipe 10 are connected to the pump body 1. During operation, the movement of the piston 2 allows liquid to enter the pump body 1 through the inlet pipe 9 and exit through the outlet pipe 10. Therefore, by precisely controlling the speed and distance of the piston 2's movement, the flow rate and volume of the liquid being drawn in or discharged can be precisely controlled.

[0021] There are two pistons 2, which are spaced apart along the length of the inner cavity of the pump body 1. Each piston 2 is movably and sealingly assembled with the inner cavity of the pump body 1. The specific structure of the movably and sealingly assembled pistons includes, but is not limited to, rubber pistons, single or multiple rubber rings, or other sealing structures. The two pistons 2 divide the inner cavity of the pump body 1 into a first sealed cavity A1, a sterilization air cavity 8, and a second sealed cavity B1 arranged sequentially. A linkage rod 3 is fixedly connected between the two pistons 2, located in the sterilization air cavity 8, and is used to achieve linkage between the two pistons 2.

[0022] A mounting base 5 is provided in the sterilization air chamber 8. The mounting base 5 is fixedly sleeved on the middle of the linkage rod 3 and is set perpendicular to the linkage rod 3. A connecting rod 6 is provided on the mounting base 5. The outer end of the connecting rod 6 away from the mounting base 5 extends out of the pump body 1. The connecting rod 6 is used to drive the piston 2 in linkage. Specifically, the connecting rod 6 and the mounting base 5 are connected through a slot structure, which facilitates the connection and separation of the two. An electric cylinder is connected to the outer end of the connecting rod 6 away from the mounting base 5. The electric cylinder is used to drive the movement of the connecting rod 6, thereby driving the piston 2 in linkage.

[0023] An opening is provided on the pump body 1 to allow the connecting rod 6 to pass during its movement. To fully ensure the isolation of the liquid from the external atmosphere and prevent bacteria, dust, and other contaminants from entering the liquid, two flexible tubes 7 are installed in the pump body 1. These two flexible tubes 7 are symmetrically arranged on both sides of the mounting base 5, with each end of the flexible tube 7 connected to the mounting base 5 and the inner cavity of the pump body 1, respectively. This not only ensures the sealing of the sterilization chamber 8 by blocking the opening through the flexible tubes 7, completely isolating the piston 2 from the external atmosphere, but also does not affect the movement of the connecting rod 6. Specifically, the structure of the flexible tube 7 includes, but is not limited to, a bellows, a flexible diaphragm, a flexible film, or an elastic film.

[0024] The sterility of the sterilization chamber 8 is mainly achieved through the overall high-temperature sterilization of this invention, or through production in a sterile production workshop. The sterilization chamber 8 is divided into a first sterilization chamber 81 and a second sterilization chamber 82, which are arranged to the left and right, by the mounting base 5 and the flexible tube 7. The linkage rod 3 is provided with an air passage 4, and the two ends of the air passage 4 are respectively connected to the first sterilization chamber 81 and the second sterilization chamber 82, thereby realizing the connection between the first sterilization chamber 81 and the second sterilization chamber 82. When the piston 2 moves left and right to compress or stretch the flexible tube 7, the total volume of the first sterilization chamber 81 and the second sterilization chamber 82 remains unchanged, thus ensuring the air pressure balance of the first sterilization chamber 81 and the second sterilization chamber 82.

[0025] One end of the pump body 1 is provided with a first interface and a second interface, which are respectively connected to a first sealed cavity A1. The first interface is equipped with an A-side inlet check valve A1-F1, and the second interface is equipped with an A-side outlet check valve A1-F2. The other end of the pump body 1 is provided with a third interface and a fourth interface, which are respectively connected to a second sealed cavity B1. The third interface is equipped with a B-side inlet check valve B1-F1, and the fourth interface is equipped with a B-side outlet check valve B1-F2. Specifically, the first and third interfaces are both connected to the inlet pipe 9, and the second and fourth interfaces are both connected to the outlet pipe 10. The four check valves are used to control the flow direction of the liquid and prevent backflow. Specific structures include, but are not limited to, diaphragm type, ball bearing type, and duckbill type.

[0026] When the electric cylinder drives the connecting rod 6 to move the two pistons 2 in conjunction towards the second sealed chamber B1, external liquid can be controlled to flow into the first sealed chamber A1 through the inlet pipe 9 and the A-side inlet check valves A1-F1. Simultaneously, liquid in the second sealed chamber B1 is controlled to flow outward through the four-way check valves B1-F2 and enter the outlet pipe 10. The overall design achieves dual suction and dual discharge of liquid in the pump body 1 by controlling the reciprocating motion of piston 2, which alternately draws in and discharges liquid from the first sealed chamber A1 and the second sealed chamber B1. This improves the continuity of liquid flow. Furthermore, by controlling the rotation speed and number of revolutions of the electric cylinder, the movement speed and distance of piston 2 can be precisely controlled, thereby accurately controlling the flow rate and volume of liquid drawn in or discharged. This liquid balance control does not rely on high-precision sensors such as flow meters, exhibits good tolerance to vibration and shock environments, and is suitable for mobile applications. Simultaneously, based on the patient's physical condition and the cross-sectional area of ​​piston 2, the movement speed of piston 2 is controlled by the electric cylinder to adapt the liquid flow rate to the patient's body.

[0027] In use, when the inlet pipe 9 is connected to the dialysate and the outlet pipe 10 is connected to the dialysate inlet of the dialyzer, the dialysate can be injected into the dialyzer by controlling the electric cylinder, and the flow rate and volume of the dialysate injection can be precisely controlled. When the inlet pipe 9 is connected to the waste liquid outlet of the dialyzer and the outlet pipe 10 is connected to the waste liquid collection device, the waste liquid can be removed from the dialyzer by controlling the electric cylinder, and the flow rate and volume of the removed waste liquid can be precisely controlled. When performing blood purification, multiple versions of this invention can be used to achieve liquid injection and removal, and the total amount of liquid injected and removed can be kept the same by controlling the electric cylinder.

[0028] The main advantages of this utility model are as follows:

[0029] (1) The piston 2 and the inner cavity of the pump body 1 form a structure similar to a syringe. By precisely controlling the movement speed and distance of the piston 2, the flow rate and volume of the discharged / inhaled liquid can be precisely controlled.

[0030] (2) By alternately drawing in / expelling liquid through the first sealed chamber A1 and the second sealed chamber B1, the continuity of liquid flow can be improved.

[0031] (3) By using two of the present invention, one injects liquid into the human body and the other removes liquid from the human body, since the inner cavity diameter of the pump body 1 is the same and the cross-sectional area of ​​the piston 2 is equal, the balance accuracy of the liquid can be maximized by controlling the movement distance of the piston 2.

[0032] (4) The control of liquid balance does not rely on high-precision sensors such as liquid flow meters, and it has good tolerance to vibration and shock environments, making it suitable for mobile applications.

[0033] (5) The liquid balance control and liquid pump are integrated into one unit, and the flow distribution is carried out by a one-way valve. Compared with the traditional balance chamber structure, the number of components is reduced, the structure is simplified, and the reliability is higher.

Claims

1. A double-suction, double-discharge reciprocating syringe pump, comprising a pump body (1), an inlet pipe (9), and an outlet pipe (10), characterized in that: Two pistons (2) are arranged at intervals along the length of the inner cavity of the pump body (1), which are movably sealed and assembled with the inner cavity of the pump body (1) and divide the inner cavity of the pump body (1) into a first sealed cavity (A1), a sterilization air cavity (8), and a second sealed cavity (B1) arranged in sequence. A linkage rod (3) located in the sterilization air cavity (8) is fixedly connected between the two pistons (2) for realizing the linkage of the two pistons (2). One end of the pump body (1) is provided with a first interface and a second interface respectively communicating with the first sealed cavity (A1). The other end of the pump body (1) is provided with a third interface and a fourth interface that are respectively connected to the second sealed chamber (B1). The first interface and the third interface are both connected to the inlet pipe (9), and the second interface and the fourth interface are both connected to the outlet pipe (10). The first interface is provided with an A-side inlet check valve (A1-F1), the second interface is provided with an A-side outlet check valve (A1-F2), the third interface is provided with a B-side inlet check valve (B1-F1), and the fourth interface is provided with a B-side outlet check valve (B1-F2).

2. The double-suction, double-discharge reciprocating injection pump according to claim 1, characterized in that: The sterilization air chamber (8) is provided with a mounting seat (5) fixedly sleeved in the middle of the linkage rod (3) and perpendicular to the linkage rod (3). The mounting seat (5) is connected by a connecting rod (6) that passes through the pump body (1) and is used to drive the piston (2) in linkage.

3. The double-suction, double-discharge reciprocating injection pump according to claim 2, characterized in that: The outer end of the connecting rod (6) away from the mounting base (5) is connected to an electric cylinder for driving the connecting rod (6) to move so as to drive the piston (2) in conjunction with the connecting rod (6).

4. The double-suction, double-discharge reciprocating injection pump according to claim 2, characterized in that: The pump body (1) has an opening for avoiding the connecting rod (6) when the connecting rod (6) moves; the pump body (1) is provided with a flexible tube (7) symmetrically arranged on both sides of the mounting base (5) and connected to the mounting base (5) and the inner cavity of the pump body (1) respectively to block the opening to ensure the airtightness of the sterilization air chamber (8) and to divide the sterilization air chamber (8) into a first sterilization air chamber (81) and a second sterilization air chamber (82).

5. A double-suction, double-discharge reciprocating injection pump according to claim 4, characterized in that: The linkage rod (3) is provided with an air passage (4) for connecting the first sterilization air chamber (81) and the second sterilization air chamber (82) to ensure the air pressure balance between the first sterilization air chamber (81) and the second sterilization air chamber (82).

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