CN216692214U

CN216692214U - High-precision rotary valve for micro-flow liquid metering

Info

Publication number: CN216692214U
Application number: CN202123271620.3U
Authority: CN
Inventors: 柳和生; 匡唐清; 胡礼彬; 朱瑶瑶; 罗杰
Original assignee: East China Jiaotong University
Current assignee: East China Jiaotong University
Priority date: 2021-12-23
Filing date: 2021-12-23
Publication date: 2022-06-07
Anticipated expiration: 2031-12-23

Abstract

The utility model provides a high-precision rotary valve for metering micro-flow liquid, which consists of a stepping motor, a frame, a rotary ring transmission part, a valve body, an elastic part and a positioning mechanism. The valve body is internally provided with two fixed valve plates and a movable valve plate, the three valve plates are respectively provided with channels with different volumes, and the movable valve plate is assembled between the two fixed valve plates and can rotate relative to the movable valve plate; the rotating ring transmission part is connected with the movable valve plate by adopting an elastic part, and is matched with a positioning mechanism consisting of a positioning groove and a positioning pin for use, so that the movable valve plate is accurately positioned; the motor drives the rotating ring transmission part to rotate, the flexible transmission of the motor to the movable valve plate is realized by the elastic part, and the movable valve plate rotates to different positions to form different combined channels, so that the sample introduction and sample discharge processes are completed. The assembly is driven by a stepping motor, and the motion state of the movable valve plate is controlled by adopting a mode of combining the elastic piece and the positioning mechanism, so that not only is the accurate positioning between the combined channels ensured, but also the assembly difficulty and the development cost of the assembly are reduced.

Description

High-precision rotary valve for micro-flow liquid metering

Technical Field

The utility model relates to the field of fluid measurement, in particular to a high-precision rotary valve for micro-flow liquid metering.

Background

The liquid metering valve is used as a liquid metering device commonly used in the fields of chemistry, biomedicine and the like, and the component mainly comprises a driving element, a metering valve and the like, wherein the metering valve comprises a fixed valve plate, a movable valve plate, a valve shaft and other elements, the valve plate is provided with a fluid channel, different combined flow channels are switched by controlling the rotation angle or displacement of the movable valve plate so as to complete the processes of liquid sampling, sample discharging and the like, and the precision of metering is required to be accurate, so that the precision of the movable valve plate and other components is greatly required. Common driving modes of the movable valve plate comprise cylinder driving and direct current motor driving, and although accurate positioning can be realized by the cylinder driving, the cylinder driving has many components, large occupied space, difficult maintenance and high control requirement; in the driving of a direct current motor, the precision requirement on parts is high, the size chain is long, and the positioning precision of a movable valve plate is influenced.

SUMMERY OF THE UTILITY MODEL

The utility model mainly aims to provide a high-precision rotary valve for metering micro-flow liquid, which has a simple structure and adjustable metering and can reduce the requirement on the positioning precision of a movable valve plate.

In order to achieve the purpose, the utility model adopts the technical scheme that: provided is a high-precision rotary valve for micro-flow liquid metering, comprising:

in one embodiment, the high-precision rotary valve component for micro-flow liquid metering comprises a stepping motor, a frame, a rotary ring transmission part, a valve body, an elastic element and a positioning mechanism; the valve body is internally provided with a coaxial valve shaft, two fixed valve plates and a movable valve plate, and the three valve plates are arranged in a side-by-side and close fit manner; the two fixed valve plates are fixed on the frame, and the movable valve plate can rotate relative to the fixed valve plates; the positioning mechanism consists of a limiting groove on the movable valve plate and a limiting pin on the fixed valve plate II, and the limiting groove is provided with a first limiting surface and a second limiting surface.

In one embodiment, the stepping motor is provided with a motor shaft, and the motor shaft is connected with the rotating ring transmission member through a key so as to realize synchronous rotation of the motor and the rotating ring transmission member.

In one embodiment, the swivel drive is positioned on the frame and the valve shaft by bearings.

In one embodiment, the movable valve plate is provided with a boss, two elastic members are connected to two sides of the boss, one end of each elastic member is connected with the rotating ring transmission member, and the other end of each elastic member is connected with the boss.

In one embodiment, the two fixed valve plates are respectively provided with four sample feeding channels and sample discharging channels with different volumes which are arranged along the radius direction, and the sample feeding channels and the sample sampling channels are distributed in a staggered mode at a certain angle.

In one embodiment, the movable valve plate is provided with four sampling channels with different volumes arranged along the radius direction.

In one embodiment, the valve shaft and the fixed valve plate are integrally processed, and the valve shaft is separated from the motor shaft and the rotating ring transmission piece and is coaxial with the motor shaft and the rotating ring transmission piece.

One or more technical solutions described above in the embodiments of the present invention have at least the following technical effects or advantages:

the embodiment of the utility model provides a high-precision rotary valve for metering micro-flow liquid, the aperture of a sampling channel is smaller than the apertures of a sample introduction channel and a sample discharge channel, and the centering requirement among the channels can be reduced; a plurality of fluid channels with different volumes are arranged to realize metering adjustability; the fixed valve plate is pressed through the bolt and the spring, so that the pressing force of the contact surface of the fixed valve plate and the movable valve plate can be flexibly controlled; the elastic piece and the rotating ring transmission piece are used as media for connecting the motor shaft and the movable valve plate, so that the flexible transmission of the motor to the movable valve plate is realized, and meanwhile, the high-precision positioning of the movable valve plate can be ensured by matching with a positioning mechanism; the components are driven by the stepping motor, and the components are fewer, compact in structure and convenient to disassemble and assemble.

Drawings

In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings needed for the embodiments or the prior art descriptions will be briefly described below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and it is obvious for those skilled in the art to obtain other drawings without creative efforts.

FIG. 1 is a schematic structural diagram of a high-precision rotary valve for micro-flow liquid metering according to the present invention;

FIG. 2 is a schematic sectional view taken along the line A-A in FIG. 1;

FIG. 3 is a schematic structural view of two stationary plates according to an embodiment of the present invention;

FIGS. 4 to 7 are schematic structural diagrams of a sample injection process of the liquid metering valve according to the present invention;

fig. 8 to 11 are schematic views showing the structure of the liquid metering valve discharging process of the present invention.

Wherein, in the figures, the respective reference numerals:

1. a motor; 11. a motor shaft; 2. a frame; 3. a swivel drive member; 31. a key; 32. a first bearing; 33. a second bearing; 4. a valve body; 41. a fixed valve plate 411 and a sample feeding channel; 412. a stock layout channel; 42. a movable valve plate; 421; a sampling channel; 422. a boss; 423. a limiting groove; 4231. a first limit surface; 4232. a second limiting surface; 43. a fixed valve plate; 431. a sample introduction channel; 432. a stock layout channel; 433. a limit pin; 44. a valve shaft; 45. a contact surface; 5 an elastic member.

Detailed Description

Reference will now be made in detail to embodiments of the present invention, examples of which are illustrated in the accompanying drawings, wherein like or similar reference numerals refer to the same or similar elements or elements having the same or similar function throughout. The embodiments described below with reference to the drawings are illustrative and intended to be illustrative of the utility model and are not to be construed as limiting the utility model.

In the description of the present invention, it is to be understood that the terms "length", "width", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", and the like, indicate orientations or positional relationships based on the orientations or positional relationships illustrated in the drawings, and are used merely for convenience in describing the present invention and for simplicity in description, and do not indicate or imply that the devices or elements referred to must have a particular orientation, be constructed in a particular orientation, and be operated, and thus, are not to be construed as limiting the present invention.

Furthermore, the terms "first", "second" and "first" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of the present invention, "a plurality" means two or more unless specifically defined otherwise.

In the present invention, unless otherwise expressly stated or limited, the terms "mounted," "connected," "secured," and the like are to be construed broadly and can, for example, be fixedly connected, detachably connected, or integrally formed; can be mechanically or electrically connected; either directly or indirectly through intervening media, either internally or in any other relationship. The specific meanings of the above terms in the present invention can be understood by those skilled in the art according to specific situations.

Referring to fig. 1 to 3, a high precision liquid rotary valve includes a stepping motor 1, a frame 2, a rotary transmission member 3, a valve body 4 and an elastic member 5. The motor 1 is provided with a motor shaft 11; the swivel transmission 3 is provided with a key 31,

bearings

32 and 33; the valve body 4 is provided with a fixed valve plate 41, a movable valve plate 42, a fixed valve plate 43 and a valve shaft 44 which are coaxial, the valve shaft 44, the rotating ring transmission member 3 and the motor shaft 11 are coaxial, and the valve shaft and the motor shaft 11 are arranged separately. The movable valve plate is clamped by the two fixed valve plates, and the contact surface 45 between the two adjacent valve plates provides a sealing effect for the combined channel; the two fixed valve plates are fixed on the frame by bolts and springs and are used for providing pressing force between the valve plates; the movable valve plate is provided with a boss 422, two sides of the boss are respectively provided with an elastic piece 51 and an elastic piece 52, one end of each elastic piece is connected with the boss 422, and the other end is connected with the rotating ring transmission piece 3.

The first fixed valve plate 41 is provided with a sample feeding channel 411 and a sample discharging channel 412, the sample feeding channel and the sample discharging channel are symmetrically distributed around the vertical direction, and four channels with different volumes are arranged along the radius direction and are used for sample feeding and sample discharging; the sample inlet channel 431 and the sample outlet channel 432 on the fixed valve plate 43 are distributed in the same way as the fixed valve plate 41. The movable valve plate 42 is provided with a sampling passage 421, and four passages with different volumes are distributed along the diameter direction for intercepting liquid with different volumes. The movable valve plate 42 is provided with a limit groove 423, the limit groove is provided with a first limit surface 4231 and a second limit surface 4232, the fixed valve plate 43 is provided with a limit pin 433 protruding into the limit groove, and the limit groove and the limit pin form a positioning mechanism for positioning the movable valve plate 42.

Referring to fig. 2, at the initial installation position, the motor is not energized, the compression amount or the tension amount of the elastic members 4 at both sides of the boss is consistent, and the elastic members are in a balanced state. The motor 1 is electrified to drive the rotating ring transmission piece 3 to synchronously rotate, and the elastic piece begins to deform to form pressure difference; because of the static friction moment between the contact surfaces 45 of the fixed and movable valve plates, the movable valve plate 42 and the boss 422 thereof are stationary. When the motor 1 continues to rotate and the pressure difference between the two elastic members continues to increase, the boss 422 starts to move when the torque generated by the valve shaft 44 on the movable valve plate 42 is greater than the maximum static friction torque on the sealing surface 45 between the movable valve plate and the fixed valve plate, that is, the movable valve plate 42 starts to rotate around the valve shaft 44. When the first limit surface 4231 or the second limit surface 4232 on the limit groove 423 of the movable valve plate 42 contacts the positioning pin 431 of the fixed valve plate 43, the movable valve plate 42 stops rotating, and at this time, the sampling channel 421 on the movable valve plate 42 is connected with the

sample feeding channels

411 and 431 or the

sample discharging channels

412 and 432 on the two fixed valve plates. The motor 1 continues to drive the rotating ring transmission part 3 to rotate, the pressure difference between the two elastic parts continues to increase, but the movable valve plate 42 is limited and is in an overpressure static state, and the power is cut off until the motor 1 finishes the preset number of steps. After the power failure, the movable valve plate 42 and the boss 422 thereof are still stationary due to the friction of the contact surfaces of the fixed and movable valve plates, and one end of the elastic member connected with the rotating ring transmission member 3 returns to the balance position, and simultaneously the sample feeding or sample discharging process is completed.

The specific working flow of sample injection is as follows:

referring to fig. 4, when the stepping motor 1 is powered on, the rotating ring transmission member 3 and one end of the elastic member connected thereto are driven to rotate clockwise, and because a static friction moment exists on the sealing surface 45 between the fixed valve body and the movable valve body, the movable valve plate 42 and the boss 422 thereof are stationary, the elastic member on the left side of the boss 422 is compressed, and the elastic member on the right side is stretched, thereby generating a pressure difference. In the position i shown in fig. 4, the torque generated by the pressure differential valve plate of the two elastic members is equal to the maximum static friction torque on the sealing surface 45, and the movable valve plate 42 is in the critical rotation state, and the angle rotated by the rotating ring transmission member 3 is called the critical rotation angle.

Referring to fig. 5, the rotating ring driving member 3 continues to rotate, and after the torque generated by the pressure difference of the elastic member on the movable valve plate is greater than the maximum static friction torque on the sealing surface between the fixed and movable valve bodies, the boss 422 and the movable valve plate 42 start to rotate until the first limit surface on the movable valve plate 42 contacts the limit pin 433 on the fixed valve plate 43, and the rotation is stopped. At this time, the sampling channel on the movable valve plate 42 reaches the sampling position of the fixed valve plate 43 to form a sampling combined channel, i.e. the sampling channel 421 is aligned with the

sampling channels

411 and 431.

Referring to fig. 6, the motor 1 and the rotating ring transmission member 3 continue to rotate, the movable valve plate 42 and the boss 422 thereof are limited to be in a static state, and the pressure difference of the elastic member continues to increase until the preset number of motor steps is completed. In order to prevent the displacement of the sampling channel and the sampling channel caused by the rotation of the movable valve plate which is not in place due to the loss of the step of the stepping motor or the larger friction of the contact surface of the fixed valve plate and the movable valve plate, the set value of the angular displacement of the motor is larger than the maximum rotation angle of the movable valve plate (the maximum rotation angle is determined by the relative position between the limiting surface and the limiting pin).

Referring to fig. 7, when the step motor 1 is powered off, the movable valve plate 42 and the boss 422 thereof are still stationary due to the friction of the contact surface, and the end of the elastic member connected to the rotating ring transmission member 3 returns to the equilibrium position of the elastic member, so as to start sampling.

The specific workflow of stock layout is as follows:

with reference to fig. 8 to 11, the sample discharge process is the reverse process of the sample injection process in fig. 4 to 7. After the sample injection is finished, namely the sample injection combined channels (411, 421 and 431) are filled with the liquid sample, the stepping motor 1 is electrified to drive the rotating ring transmission piece to rotate anticlockwise; when the moment generated on the sealing surface between the fixed valve body and the movable valve body by the pressure difference between the two elastic members is larger than the maximum static friction moment, the movable valve plate 42 starts to rotate until the second limiting surface of the movable valve plate contacts the positioning pin and stops rotating, and at the moment, the sampling channel 521 of the movable valve plate is aligned with the ports of the stock layout channels 512 and 532 on the fixed valve plate to form a stock layout combined channel; the stepping motor 1 continues to rotate until the set step number is finished, and the movable valve plate is still in a static state at the moment; the motor cuts off the power supply, and the boss is motionless, and the swivel driving medium returns to balanced position rather than the elastic component one end that links to each other, passes through the sample in the sample passage and arranges the appearance combination passageway simultaneously and discharges, accomplishes the stock layout process.

According to the utility model, the elastic piece is respectively connected with the movable valve plate and the rotating ring transmission piece, and the movable valve plate is limited by the positioning mechanism consisting of the positioning pin and the positioning groove, so that the defect that the positioning precision of the stepping motor is difficult to control is overcome. Meanwhile, a plurality of different volume channels are arranged on the valve body, so that fluid samples with different metering amounts can be intercepted according to requirements, and variable metering is realized.

The present invention is not limited to the above preferred embodiments, and any modifications, equivalent substitutions and improvements made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. The utility model provides a be used for high-accuracy rotary valve of micro-flow liquid measurement which characterized in that:

the high-precision rotary valve component for micro-flow liquid metering comprises a stepping motor, a rack, a rotary ring transmission part, a valve body, an elastic element and a positioning mechanism; the valve body is internally provided with a coaxial valve shaft, two fixed valve plates and a movable valve plate, and the three valve plates are arranged in a side-by-side and close fit manner; the two fixed valve plates are fixed on the frame, and the movable valve plate can rotate relative to the fixed valve plates; the positioning mechanism consists of a limiting groove on the movable valve plate and a limiting pin on the fixed valve plate II, and the limiting groove is provided with a first limiting surface and a second limiting surface.

2. A high precision rotary valve for micro-flow liquid metering in accordance with claim 1 wherein:

the stepping motor is provided with a motor shaft, and the motor shaft is connected with the rotating transmission part through a key so as to realize synchronous rotation of the motor and the rotating transmission part.

3. A high precision rotary valve for micro-flow liquid metering in accordance with claim 1 wherein:

the rotating ring transmission piece is positioned on the frame and the valve shaft through a bearing.

4. A high precision rotary valve for micro-flow liquid metering in accordance with claim 1 wherein:

the movable valve plate is provided with a boss, two elastic pieces are connected to two sides of the boss, one end of each elastic piece is connected with the rotating ring transmission piece, and the other end of each elastic piece is connected with the boss.

5. A high precision rotary valve for micro-flow liquid metering in accordance with claim 1 wherein:

the two fixed valve plates are respectively provided with four sampling channels and sample discharging channels with different volumes which are arranged along the radius direction, and the sampling channels are distributed in a staggered mode by a certain angle.

6. A high precision rotary valve for micro-flow liquid metering in accordance with claim 1 wherein:

the movable valve plate is provided with four sampling channels with different volumes arranged along the radius direction.

7. A high precision rotary valve for micro-flow liquid metering in accordance with claim 1 wherein:

the valve shaft and the fixed valve plate are integrally processed, the valve shaft is separated from the motor shaft and the rotating ring transmission piece, and the valve shaft, the motor shaft and the rotating ring transmission piece are coaxial.