Automatic flow rate regulating piston pump and its control pump system for flow cell dissolution apparatus

Abstract

The present invention discloses an automatic flow regulating piston pump for a flow cell method dissolution instrument, comprising a motor, a rotating shaft, a piston rod, a pump head and a pump head moving assembly, wherein the pump head is mounted on the pump head moving assembly, one end of the piston rod is connected to the pump head, and the other end is connected to the rotating shaft, the motor is mounted on the other end of the rotating shaft, and the rotating shaft of the motor is connected to the rotating shaft. The automatic flow regulating piston pump for a flow cell method dissolution instrument of the present invention adjusts the angle between the piston rod and the pump head through the pump head moving assembly to achieve flow regulation, has a simple structure, is easy to operate, and can achieve precise flow control.

Description

Technical Field

[0001] The invention belongs to the technical field of drug research and development and quality control test and detection equipment, and specifically relates to an automatic flow regulating piston pump of a flow cell method dissolution instrument and a control pump system thereof. Background Art

[0002] As a method for testing drug properties, dissolution testing plays an important role in the development, imitation and quality consistency evaluation of drug preparations after approval. The United States Pharmacopoeia divides drug dissolution apparatus into methods 1-7, among which the fourth method is the flow-through method, and the first draft for comments of the 2020 edition of the Chinese Pharmacopoeia is the sixth method.

[0003] At present, the paddle method and basket method of the Chinese Pharmacopoeia have some limitations: 1. The dissolution medium limits the in vitro and in vivo correlation; 2. In the paddle method experiment, insoluble excipients form a cone at the bottom of the dissolution cup, affecting drug dissolution; 3. The fluid mechanics generated by the rotation of the basket or paddle method are very different from those of the gastrointestinal tract; 4. Excessive differentiation or insufficient differentiation is prone to occur.

[0004] At present, the pump used for flow control of flow cell dissolution apparatus on the market is a syringe pump. Since the pharmacopoeia requires a pulsation frequency of 120±10 strokes / min, at high flow, the movement speed is too fast, and the distance error of the stepper motor is accumulated, resulting in inaccurate flow. The rubber piston rubs against the glass syringe, has poor wear resistance, and unstable quality. Summary of the invention

[0005] In view of the problems existing in the prior art, the present invention provides an automatic flow regulating piston pump for a flow cell method dissolution apparatus and a control pump system thereof.

[0006] The technical solution of the present invention is:

[0007] A flow cell method dissolution instrument automatic flow regulating piston pump comprises a motor, a rotating shaft, a piston rod, a pump head and a pump head moving assembly, wherein the pump head is mounted on the pump head moving assembly, one end of the piston rod is connected to the pump head, and the other end is connected to the rotating shaft, the motor is mounted on the other end of the rotating shaft, and the rotating shaft of the motor is connected to the rotating shaft.

[0008] Preferably, a coupling is installed between the motor and the rotating shaft.

[0009] Preferably, the piston rod is a ceramic piston rod.

[0010] Preferably, the pump head comprises a pump chamber, an outlet check valve and an inlet check valve, the pump chamber is connected to the piston rod, and the outlet check valve and the inlet check valve are respectively located at the upper and lower ends of the pump chamber.

[0011] Preferably, the pump head moving assembly includes a support frame, a motor bracket and a rotating motor, the pump chamber of the pump head is located in the support frame, the motor bracket is installed on the side wall of the support frame, and the rotating motor is installed on the motor bracket for rotating the support frame.

[0012] The present invention also includes a control pump system, which includes the above-mentioned flow cell method dissolution instrument automatic flow regulating piston pump, an electronic balance and a sample injection rack, wherein the flow cell method dissolution instrument automatic flow regulating piston pump is installed on the sample injection rack, and the electronic balance is placed at the bottom of the sample injection rack and below the flow cell method dissolution instrument automatic flow regulating piston pump.

[0013] Preferably, the number of the flow cell dissolution apparatus's automatically adjustable flow piston pumps is 7.

[0014] The technical solution of the present invention has the following beneficial effects:

[0015] Advantages of flow-through cell method

[0016] 1. The type of dissolution medium can be changed during the test, which is closer to the gastrointestinal PH environment; 2. The sample is continuously exposed to a constant laminar flow, which is closer to the gastrointestinal fluid environment; 3. It has good sink conditions; 4. It has good biological relevance and effective discrimination.

[0017] The flow cell dissolution apparatus of the present invention automatically adjusts the flow rate by adjusting the angle between the piston rod and the pump head through a pump head moving assembly. The structure is simple and the operation is convenient. The control pump system consists of 7 piston pumps, and the flow of each piston pump is independently controlled, so that precise flow control can be achieved. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 It is a schematic diagram of the structure of the piston pump of the present invention;

[0019] Figure 2 An exploded view of the piston pump of the present invention;

[0020] Figure 3 A cross-sectional view of a piston pump of the present invention;

[0021] Figure 4 A schematic structural diagram of the control pump system of the present invention. DETAILED DESCRIPTION

[0022] The present invention is further described below in conjunction with the accompanying drawings and specific embodiments.

[0023] Reference Figures 1 to 4The present invention provides an automatic flow regulating piston pump for a flow cell dissolution apparatus, comprising a motor 1, a rotating shaft 2, a piston rod 3, a pump head 4 and a pump head moving assembly 5, wherein the pump head 4 is mounted on the pump head moving assembly 5, one end of the piston rod 3 is connected to the pump head 4, and the other end is connected to the rotating shaft 2, the motor 1 is mounted on the other end of the rotating shaft 2, and the rotating shaft of the motor 1 is connected to the rotating shaft 2.

[0024] A coupling 6 is also installed between the motor 1 and the rotating shaft 2 .

[0025] The piston rod 3 is a ceramic piston rod.

[0026] The pump head 4 includes a pump chamber 401, an outlet check valve 402 and an inlet check valve 403. The pump chamber 401 is connected to the piston rod 3. The outlet check valve 402 and the inlet check valve 403 are respectively located at the upper and lower ends of the pump chamber 401. Preferably, one end of the piston rod extends into the pump chamber of the pump head, and the other end is located in the rotating shaft and connected to the rotating shaft through a universal ball a.

[0027] The pump head moving assembly 5 includes a support frame 501, a motor bracket 502 and a rotating motor 503. The pump chamber 401 of the pump head 4 is located in the support frame 501. The motor bracket 502 is installed on the side wall of the support frame 501. The rotating motor 503 is installed on the motor bracket 502 for rotating the support frame 501.

[0028] The present invention also includes a control pump system, which includes the above-mentioned flow cell method dissolution instrument automatic flow regulating piston pump A, an electronic balance 7 and a sample injection rack 8, wherein the flow cell method dissolution instrument automatic flow regulating piston pump is installed on the sample injection rack 8, and the electronic balance 7 is placed at the bottom of the sample injection rack 8 and below the flow cell method dissolution instrument automatic flow regulating piston pump. A sample collection cup 9 is also placed on the electronic balance 7.

[0029] The number of the automatic flow rate regulating piston pumps of the flow cell dissolution apparatus is 7.

[0030] The working principle of the present invention is as follows: during the reciprocating motion of the piston rod, when the piston rod moves outward, the outlet check valve 402 is closed under the action of deadweight and pressure difference, and the inlet check valve 403 is opened under the action of pressure difference. Liquid is sucked into the pump chamber 401; when the piston rod is pressed inward, the pressure in the pump chamber 401 increases, so that the inlet check valve 403 is closed, and the outlet check valve 402 is opened to press the liquid into the outlet pipe. The flow rate can be changed by changing the frequency of the piston reciprocating and the volume of the liquid sucked into the pump chamber 401 each time. The flow rate = the frequency of the piston reciprocating × the volume of the liquid sucked into the pump chamber each time. The pharmacopoeia requires the use of the flow cell method for dissolution inspection, and the flow rate and pulse frequency should be specified. Therefore, the flow rate can only be changed by changing the volume of the liquid sucked into the pump chamber each time. The volume of the liquid sucked into the pump chamber 401 is determined by the size of the angle between the piston rod 3 and the pump head 4. Therefore, the flow rate is adjusted by adjusting the angle between the piston rod 3 and the pump head 4 through the pump head moving component 5. Since the flow cell dissolution apparatus will produce solid-liquid turbidity during the experiment, the pharmacopoeia requires the design of filtration in the flow system. Filtration will increase the system pressure and cause inaccurate flow. The motor that changes the angle movement also has errors. The error amount is obtained by weighing with an electronic balance 7, and the error amount is fed back to the flow calibration control system. After measurement, the flow calibration control system accurately adjusts the angle between the piston rod 3 and the pump head 4 to achieve accurate flow control. The piston rod is made of ceramic piston rod, which is durable.

[0031] The above description is only a preferred embodiment of the present invention, and does not limit the patent scope of the present invention. All equivalent structural changes made by using the contents of the present invention specification and drawings under the inventive concept of the present invention, or directly / indirectly applied in other related technical fields are included in the patent protection scope of the present invention.

Claims

1. A control pump system, Features: It comprises an automatic flow regulating piston pump of a flow cell method dissolution apparatus, an electronic balance and a sample injection rack, wherein the automatic flow regulating piston pump of the flow cell method dissolution apparatus is installed on the sample injection rack, and the electronic balance is placed at the bottom of the sample injection rack and below the automatic flow regulating piston pump of the flow cell method dissolution apparatus; The automatic flow regulating piston pump of the flow cell dissolution apparatus comprises a motor, a rotating shaft, a piston rod, a pump head and a pump head moving assembly, wherein the pump head is mounted on the pump head moving assembly, one end of the piston rod is connected to the pump head, and the other end is connected to the rotating shaft, the motor is mounted on the other end of the rotating shaft, and the rotating shaft of the motor is connected to the rotating shaft; A coupling is also installed between the motor and the rotating shaft; The piston rod is a ceramic piston rod; The pump head comprises a pump chamber, an outlet check valve and an inlet check valve, the pump chamber is connected to the piston rod, and the outlet check valve and the inlet check valve are respectively located at the upper and lower ends of the pump chamber; The pump head moving assembly includes a support frame, a motor support and a rotating motor. The pump chamber of the pump head is located in the support frame. The motor support is installed on the side wall of the support frame. The rotating motor is installed on the motor support and is used to rotate the support frame.

2. The control pump system according to claim 1, Features: The number of the automatic flow rate regulating piston pumps of the flow cell dissolution apparatus is 7.

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