CN215333341U

CN215333341U - Peristaltic pump

Info

Publication number: CN215333341U
Application number: CN202121234305.0U
Authority: CN
Inventors: 王冲; 宋晓峰
Original assignee: Suzhou Weizhi Technology Co ltd
Current assignee: Suzhou Weizhi Technology Co ltd
Priority date: 2021-06-03
Filing date: 2021-06-03
Publication date: 2021-12-28
Anticipated expiration: 2031-06-03

Abstract

The utility model provides a peristaltic pump, which comprises a driving mechanism, a transmission mechanism, a hose, a pressure plate and a pressure wheel, wherein the hose is arranged on the driving mechanism; the driving mechanism is connected with the transmission mechanism and can drive the transmission mechanism to move; the transmission mechanism is connected with the pressing wheel and can drive the pressing wheel to move; the peristaltic pump has the advantages of simple structure, easiness in preparation, capability of effectively avoiding hose deformation, adhesion and incapability of springback caused by long-time extrusion of the hose, good service stability and long service life.

Description

Peristaltic pump

Technical Field

The utility model relates to the field of peristaltic pumps, in particular to a peristaltic pump capable of extruding a hose up and down.

Background

Peristaltic pumps act like clamps that clamp a fluid-filled hose and slide the fluid forward inside the tube as the clamp slides forward. Peristaltic pumps use the same principle, replacing the clamps with rollers. By alternately squeezing and releasing the flexible delivery hose, a negative pressure is created within the tube, causing the liquid to flow therewith. Generally, the peristaltic pump is composed of a pump shell with a circular inner cavity, rollers and a hose, wherein the hose is arranged in the pump shell. The hose is squeezed by the roller to form a closed cut-off point which follows the roller as the roller rotates. The hose will return to its natural state after the roller has been removed and a vacuum will be created in the hose, drawing in the fluid and being squeezed out by the next roller.

The peristaltic pump conveys liquid mainly by the rotation of the roller along the axial direction and extruding the hose along the radial direction, and in the liquid conveying process, the closing point on the hose can move along with the roller along with the rotation of the roller to realize liquid conveying, so that the hose can be extruded by the roller for a long time, but the hose can be deformed and cannot rebound when the roller extrudes the hose for a long time. Even when the diaphragm pump is in the shutdown state, the gyro wheel still can continue to extrude the hose, remains under the effect of liquid in the hose this moment, and the easy adhesion of the part that the hose was extruded for liquid can't pass through.

The present application is particularly proposed to solve the above problems.

SUMMERY OF THE UTILITY MODEL

The utility model designs a peristaltic pump to solve the problem that a hose in the conventional peristaltic pump is extruded by rollers for a long time, is easy to deform, adhere and cannot rebound, so that the peristaltic pump fails.

In order to solve the problems, the utility model discloses a peristaltic pump which comprises a driving mechanism, a transmission mechanism, a hose, a pressure plate and a pressure wheel; the driving mechanism is connected with the transmission mechanism and can drive the transmission mechanism to move; the transmission mechanism is connected with the pressing wheel and can drive the pressing wheel to move; the pinch roller with the pressure disk is connected, the pinch roller can drive the pressure disk is to being close to the one side motion of hose, later the pressure disk can be through rotatory extrusion the hose, makes the hose can carry liquid.

Furthermore, actuating mechanism can drive mechanism rotates, drive mechanism can drive the pinch roller rotates, the pinch roller can be through rotatory extrusion the pressure disk, make the pressure disk is to being close to the one side motion of hose.

Furthermore, the transmission mechanism comprises a planetary gear train and a power output shaft, one end of the planetary gear train is connected with the driving mechanism, the other end of the planetary gear train is connected with the power output shaft, the pressing wheel is connected with the power output shaft, and the pressing wheel can rotate synchronously along with the power output shaft.

Further, the hose includes hose body and supporting disk, the supporting disk with the pressure disk sets up relatively.

Furthermore, the pressure plate is provided with a mounting hole, and the pressing wheel is arranged in the mounting hole.

Further, set up direction inclined plane in the mounting hole, the one end of pinch roller is inserted in the mounting hole, and with the direction inclined plane contacts, the pinch roller is in when drive mechanism's drive is rotatory down, the tip of pinch roller will be along direction inclined plane rotates, and can pass through direction inclined plane extrusion the pressure disk makes the pressure disk is to being close to the one end motion of hose.

Furthermore, set up joint spare in the mounting hole, it is corresponding, set up the locating part on the surface of pinch roller, joint spare can with the locating part is in the same place through rotatory joint.

Furthermore, the joint piece is arranged on the inner side of the mounting hole, correspondingly, the limiting piece is arranged on the outer side of the pressing wheel, and the joint piece and the limiting piece are arranged in a crossed mode.

Furthermore, the end part of the pinch roller is contacted with the guide inclined plane through the limiting piece, and the limiting piece is positioned at the lowest point of the guide inclined plane in a natural state; when the pinch roller is rotated to extrude the pressure plate, the limiting part can rotate to the highest point of the guide inclined plane.

Furthermore, the peristaltic pump also comprises an elastic piece, the elastic piece is sleeved on the power output shaft, and when the pressing wheel rotates to press the pressing plate, the elastic piece is compressed by the pressing plate; when the peristaltic pump stops working, the elastic piece restores to deform and pushes the pressure plate back to the initial position.

Further, before the limiting part and the clamping part are rotationally clamped together, the pressing wheel can drive the pressing disc to move towards one side close to the hose; after locating part and the rotatory joint of joint spare are in the same place, the pressure disk will follow the pinch roller is synchronous to be rotated, just the pressure disk can be through rotatory extrusion the hose is in order to carry liquid.

Further, the surface that the pressure disk is close to the hose is called the crimping face, be provided with a plurality of fretworks portion on the pressure disk, set up the gyro wheel in the fretwork portion, gyro wheel and pressure disk rotatable coupling, the gyro wheel protrusion in the crimping face, the pressure disk passes through the gyro wheel is rotatory to be extruded the hose is in order to carry liquid.

The diaphragm pump described in this application has the following advantages:

firstly, the structure is simple, and the preparation and the implementation are easy;

secondly, when the peristaltic pump is used, the hose is extruded and released through the up-and-down movement of the pressure plate, so that the deformation, adhesion and incapability of rebounding of the hose caused by long-time extrusion of the hose can be effectively avoided, and the peristaltic pump is good in use stability and long in service life;

third, under standby state, the pressure disk can lead to the elastic component and reply to initial position, avoids long-time extrusion to the hose under the standby state, can further improve equipment's life by a wide margin.

Drawings

FIG. 1 is an exploded view of the diaphragm pump of the present invention;

FIG. 2 is a schematic view of the platen according to the present invention;

FIG. 3 is a schematic view of the platen of the present invention from another perspective;

FIG. 4 is a schematic diagram of the structure of the pressing wheel according to the present invention;

FIG. 5 is a schematic diagram of the puck according to the present invention shown in another perspective;

fig. 6 is a schematic sectional structure view of the diaphragm pump according to the present invention.

Description of reference numerals:

1. a drive mechanism; 101. a motor; 102. an output shaft; 2. a transmission mechanism; 201. a planetary gear train; 202. a power take-off pan; 203. a power take-off shaft; 3. a hose; 301. a hose body; 302. a support disc; 4. a platen; 401. a crimping surface; 402. mounting holes; 402a, a clamping piece; 402b, a guide slope; 403. a hollow-out section; 404. a roller; 5. a pinch roller; 501. a drive aperture; 502. a limiting member; 6. an upper cover; 7. a pump housing; 8. an elastic member.

Detailed Description

In order to make the aforementioned objects, features and advantages of the present invention comprehensible, embodiments accompanied with figures are described in detail below.

For convenience of description, in the present application, an end where the upper cover 6 is located is referred to as an upper end of the peristaltic pump, an end where the motor 101 is located is referred to as a lower end of the peristaltic pump, that is, the end where the upper cover 6 is located is in an "upper" direction, the end where the motor 101 is located is in a "lower" direction, and a straight line where a central axis of the motor 101 is located is referred to as a central axis of the peristaltic pump.

As shown in fig. 1 to 6, a diaphragm pump includes a driving mechanism 1, a transmission mechanism 2, a hose 3, a pressure plate 4 and a pressure roller 5; the driving mechanism 1 is connected with the transmission mechanism 2, and the driving mechanism 1 can drive the transmission mechanism 2 to move; the transmission mechanism 2 is connected with the pinch roller 5, and the transmission mechanism 2 can drive the pinch roller 5 to move; pinch roller 5 with pressure disk 4 is connected, pinch roller 5 can drive pressure disk 4 is to being close to the one side motion of hose 3, later pressure disk 4 can be through rotatory extrusion hose 3, make hose 3 can carry liquid.

Further, actuating mechanism 1 can drive mechanism 2 rotates, actuating mechanism 2 can drive pinch roller 5 rotates, through pinch roller 5's rotatory extrusion pressure disk 4 makes pressure disk 4 is to being close to one side motion of hose 3, later pressure disk 4 can be through rotatory extrusion hose 3, make hose 3 can carry liquid.

As some embodiments of the present application, the driving mechanism 1 includes a motor 101, the motor 101 has an output shaft 102, the output shaft 102 is connected to the transmission mechanism 2 to drive the transmission mechanism 2 to rotate, and the output shaft 102 is located on a central axis of the peristaltic pump.

As some embodiments of the present application, the transmission mechanism 2 includes a planetary gear train 201 and a power output shaft 203, the planetary gear train 201 includes a plurality of gears meshed with each other, one end of the planetary gear train 201 is connected to the output shaft 102, and the other end is connected to the power output shaft 203, so as to transmit the power generated by the motor 101 to the power output shaft 203 and drive the power output shaft 203 to rotate. The planetary gear 201 can perform the functions of transmitting the power of the motor 101 and reducing the speed.

Further, the transmission mechanism 2 further comprises a power output disc 202, and the power output disc 202 is arranged around the periphery of the planetary gear train 201 so as to prevent gears in the planetary gear train 201 from being exposed outside and affecting use and appearance.

Furthermore, the power output shaft 203 and the power output disc 202 are fixedly connected, and the power output shaft 203 and the power output disc 202 can rotate together under the driving of the planetary gear train 201.

As some embodiments of the present application, the power output disc 202 is a cylindrical structure with a closed end and a hollow interior, the power output disc 202 covers one end of the planetary gear train 201 away from the driving mechanism 1, the power output disc 202 can close an end face of the planetary gear train 201 away from the driving mechanism 1 and an annular side face of the planetary gear train 201, the power output shaft 203 is located at the center of the power output disc 202, and the power output shaft 203 is located on a central axis of the peristaltic pump.

Further, the power output disc 202 and the pressure plate 4 are arranged oppositely, and the hose 3 is arranged in a gap between the power output disc 202 and the pressure plate 4.

Further, the hose 3 includes a hose body 301 and a support plate 302, and the support plate 302 is used to fix and support the hose body 301.

Preferably, the supporting plate 302 is disposed opposite to the pressure plate 4, the supporting plate 302 is non-rotatable, and the hose body 301 is disposed in a gap between the supporting plate 302 and the pressure plate 4. So, when pressure disk 4 is to being close to hose body 301's one side motion, later rotatory extrusion hose body 301, supporting disk 302 can be right hose body 301's opposite side plays the effect of support, through supporting disk 302 with the cooperation of pressure disk 4, can reach conveniently pressure disk 4 extrudees hose body 301's effect.

Further, the hose body 301 is disposed on the support plate 302 in a U shape, and two end portions of the hose body 301 extend out of the peristaltic pump and are connected to an external mechanism.

Further, the pressure roller 5 is connected with the power output shaft 203, and the pressure roller 5 can rotate synchronously with the power output shaft 203.

As some embodiments of the present disclosure, the power output shaft 203 has a cylindrical structure, the cross section of the power output shaft 203 has a non-axisymmetric structure, such as a quadrangle, a pentagon, etc., and the pressing wheel 5 has a driving hole 501 corresponding to the power output shaft 203, so that after the power output shaft 203 is inserted into the driving hole 501, the pressing wheel 5 can rotate synchronously with the power output shaft 203.

Further, the center of pressure disk 4 sets up mounting hole 402, pinch roller 5 sets up in mounting hole 402, pinch roller 5 can be through rotatory extrusion pressure disk 4, make pressure disk 4 to the side motion that is close to hose 3.

As some embodiments of the present application, the driving hole 501 may be a blind hole or a stepped hole, and when the driving hole 501 is a stepped hole, a cross-sectional area of one end of the driving hole 501, which is far away from the power output shaft 203, is smaller, so that the power output shaft 203 can only be inserted into the driving hole 501 and drive the pressing wheel 5 to rotate, but cannot penetrate through the driving hole 501.

Further, a guide inclined plane 402b is arranged in the mounting hole 402, one end of the pressing wheel 5 is inserted into the mounting hole 402 and is in contact with the guide inclined plane 402b, and when the pressing wheel 5 is driven by the power output shaft 203 to rotate, the end of the pressing wheel 5 can rotate along the guide inclined plane 402b and can extrude the pressure plate 4 through the guide inclined plane 402b, so that the pressure plate 4 moves towards the end close to the hose 3.

Further, the guide slope 402b has a lowest point and a highest point, and the lowest point is lower than the highest point in the up-down direction of the peristaltic pump; wherein, the two sides of the lowest point are respectively provided with a highest point, after the guide inclined plane 402b extends from the highest point on one side of the lowest point to the lowest point, the guide inclined plane 402b continues to extend from the lowest point to the highest point on the other side of the lowest point, so that the guide inclined plane 402b has two inclined planes symmetrically arranged relative to the lowest point, in a natural state, the end part of the press wheel 5 is in contact with the lowest point of the guide inclined plane 402b, when the press wheel 5 rotates to press the press plate 4, because the height of the press wheel 5 is constant, the end part of the press wheel 5 rotates to the highest point along one of the lowest points, and presses the press plate 4 to the position closest to the hose 3, thereby realizing the pressing of the press plate 4 to the hose 3; when the pressing wheel 5 is not rotated continuously under the action of the power output shaft 203 any more or rotates reversely under the action of the power output shaft 203, the end part of the pressing wheel 5 rotates to the lowest point along the highest point, the extrusion on the pressure plate 4 is released, and then the extrusion on the hose 3 is released, so that the hose 3 can return to the deformation. The guide slope 402b has a structure with a lowest point and highest points located at two sides of the lowest point, so that the pressing wheel 5 can press the pressing plate 4 when rotating clockwise or counterclockwise.

Further, a clamping member 402a is arranged in the mounting hole 402, correspondingly, a limiting member 502 is arranged on the outer surface of the pressing wheel 5, and the clamping member 402a can be clamped with the limiting member 502 through rotation.

Furthermore, the clamping member 402a is a protrusion disposed inside the mounting hole 402, correspondingly, the limiting member 502 is a protrusion disposed outside the pressing wheel 5, and the clamping member 402a and the limiting member 502 are disposed in a crossing manner.

Preferably, the clamping members 402a are two protruding blocks oppositely arranged on the inner side of the mounting hole 402, correspondingly, the limiting members 502 are two protruding blocks oppositely arranged on the outer side of the pressing wheel 5, in a natural state, the clamping members 402a and the limiting members 502 are arranged in a crossed manner, and an angle between each two adjacent clamping members 402a and the limiting members 502 is 90 °.

Further, after the pressing wheel 5 is disposed in the mounting hole 402, the end of the pressing wheel 5 contacts the guiding inclined plane 402b through the limiting member 502, and in a natural state, that is, when the driving mechanism 1 does not start to work and the hose 3 is not squeezed, the limiting member 502 is located at the lowest point of the guiding inclined plane 402 b; when the pressing wheel 5 is rotated to press the pressing plate 4, the limiting member 502 can be rotated to the highest point of the guide slope 402 b. In this way, the limiting member 502 can be matched with the guiding inclined surface 402b to realize the guiding function; meanwhile, the limiting member 502 can be matched with the clamping member 402a to realize the function of positioning the rotation end point.

Specifically, according to the relative positions of the clip 402a and the limiting member 502, the connection state between the clip 402a and the limiting member 502 can be divided into a separation state and a clipping state: the clamping pieces 402a and the limiting pieces 502 are arranged in a crossed manner, and a state that any two clamping pieces 402a and any two limiting pieces 502 are not in contact is called a separation state, at this time, because the clamping pieces 402a and the limiting pieces 502 are not in contact, the pressing wheel 5 can rotate relative to the pressing plate 4 and can extrude the pressing plate 4 to one side close to the hose 3; will joint piece 402a with the state that locating part 502 contact and joint are in the same place is called the joint state, at this moment, because joint piece 402a with locating part 502 joint is in the same place, pinch roller 5 can't continue relatively pressure disk 4 is rotatory, at this moment, pressure disk 4 will along with pinch roller 5 is rotatory together, with through pinch roller 5 is rotatory the extrusion hose 3 realizes liquid transport.

As some embodiments of the present application, the lowest point of the guiding slope 402b is located between two adjacent snap-in members 402a, and the highest points on both sides of the lowest point are respectively located on two snap-in members 402a on both sides of the lowest point. Thus, when the limiting member 502 rotates to the highest point, the limiting member can be clamped with the clamping member 402a at the same time, and the rotation end point is positioned by the clamping member 402 a.

Further, a side surface of the pressure plate 4 close to the flexible tube 3 is referred to as a pressure contact surface 401, and the pressure plate 4 can directly press the flexible tube 3 through the pressure contact surface 401 to realize liquid delivery. The liquid delivery is achieved, for example, by rotating and squeezing the hose 3 by ribs radially provided on the pressure contact surface 401.

As some embodiments of the present application, a plurality of hollowed portions 403 are further disposed on the platen 4, the hollowed portions 403 are radially spaced and disposed in the platen 4, rollers 404 are disposed in the hollowed portions 403, and the rollers 404 protrude from the pressing surface 401, so that when the platen 4 moves to a side close to the hose 3, the rollers 404 will first contact with the hose 3 and squeeze the hose 3. Through the arrangement of the hollow-out part 403, an accommodating space can be formed for the dun lun 404, and the overall volume of the peristaltic pump is reduced.

As some embodiments of the present application, the roller 404 may also be directly disposed on the platen 4, that is, the hollow part 403 is not disposed on the platen 4, and the roller 404 is directly disposed on the pressing surface 401 of the platen 4.

Further, the roller 404 is rotatably disposed in the hollow portion 403, and under the action of the pressing wheel 5, the pressing plate 4 rotatably presses the hose 3 through the roller 404. The roller 404 rotates and presses the hose 3, so that the friction force applied to the hose 3 can be reduced, and the friction loss of the hose 3 can be reduced.

Further, the peristaltic pump further comprises an elastic part 8, the elastic part 8 is sleeved on the power output shaft 203, and the elastic part 8 is located between the pressure plate 4 and the power output disc 202, so that when the power output shaft 203 drives the pressure wheel 5 to rotate and the pressure wheel 5 rotates to extrude the pressure plate 4, the elastic part 8 is compressed by the pressure plate 4; when the peristaltic pump stops working, power output shaft 203 loses power, stops driving pinch roller 5 is rotatory, pinch roller 5 no longer rotates the extrusion pressure disk 4, elastic component 8 will reply deformation, will pressure disk 4 pushes back initial position.

As some examples of the present application, the elastic member 8 is a spiral spring.

Further, the peristaltic pump still includes upper cover 6 that is located its upper end, 6 lids of upper cover close on pinch roller 5 and the pressure disk 4, the tip of pinch roller 5 supports and leans on upper cover 6, so that when pinch roller 5 rotated, unable upward movement, pinch roller 5 can extrude pressure disk 4, make pressure disk 4 downstream, extrusion hose 3 carries liquid.

Furthermore, the peristaltic pump also comprises the pump housing 7, and parts of the peristaltic pump, such as the transmission mechanism 2, the hose 3, the pinch roller 5, the pressure plate 4, the elastic part 8 and the like, are arranged in the pump housing 7.

The operation and principle of the peristaltic pump described in this application is described in detail below:

first, the motor 101 is energized so that the output shaft 102 starts rotating; further, the output shaft 102 drives the planetary gear system 201, the power output disc 202 and the power output shaft 203 to rotate, and the power output shaft 203 drives the pressure wheel 5 to rotate, at this time, due to the blocking effect of the hose 3, the pressure plate 4 does not rotate, and the pressure plate 4 will move downward to press the hose 3 under the rotating and pressing effect of the pressure wheel 5, the air in the hose 3 is discharged through the rotating and pressing effect of the pressure plate 4 or the roller 404, and at the same time, the elastic element 8 will be compressed and deformed; then, the power output shaft 203 continues to drive the pressing wheel 5 to rotate, after the limiting part 502 is contacted with and clamped with the clamping part 402a, the pressing wheel 5 and the pressure plate 4 start to rotate synchronously, then the rollers 404 are driven by the pressing wheel 5 and the pressure plate 4 to rotate and extrude the hose 3, a containing cavity capable of sucking liquid is formed between every two adjacent rollers 404, liquid between every two adjacent rollers 404 is conveyed from one end of the hose 3 to the other end through the rotating and extruding of the rollers 404, so that the liquid is conveyed, and during the period, the elastic part 8 is compressed to the maximum deformation; when peristaltic pump stop work back, motor 101 outage pinch roller 5 and pressure disk 4 stop rotating, elastic component 8 reply deformation, when upwards bouncing, can with pressure disk 4 pushes away to initial position, at this moment, hose 3 no longer by pressure disk 4 extrudees, can reply deformation.

In summary, the diaphragm pump described in the present application has the following advantages: firstly, the structure is simple, and the preparation and the implementation are easy; secondly, when the device is used, the hose is extruded and released through the up-and-down movement of the pressure plate, so that the deformation, adhesion and incapability of rebounding of the hose caused by long-time extrusion of the hose can be effectively avoided, the use stability of the device is good, and the service life of the device is long; fourth, under standby state, the pressure disk can lead to the elastic component and reply to initial position, avoids long-time extrusion to the hose under the standby state, can further improve equipment's by a wide margin life.

Although the present invention is disclosed above, the present invention is not limited thereto. In the description herein, references to the description of the term "one embodiment," "some embodiments," "an illustrative embodiment," "an example," "a specific example," or "some examples" or the like mean that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the utility model. In this specification, the schematic representations of the terms used above do not necessarily refer to the same embodiment or example. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples. Various changes and modifications may be effected therein by one skilled in the art without departing from the spirit and scope of the utility model as defined in the appended claims.

Claims

1. A peristaltic pump is characterized by comprising a driving mechanism (1), a transmission mechanism (2), a hose (3), a pressure plate (4) and a pressure wheel (5);

the driving mechanism (1) is connected with the transmission mechanism (2), and the driving mechanism (1) can drive the transmission mechanism (2) to move;

the transmission mechanism (2) is connected with the pinch roller (5), and the transmission mechanism (2) can drive the pinch roller (5) to move;

pinch roller (5) with pressure disk (4) are connected, pinch roller (5) can drive pressure disk (4) are to being close to the one side motion of hose (3), later pressure disk (4) can be through rotatory extrusion hose (3), make hose (3) can carry liquid.

2. Peristaltic pump according to claim 1, characterized in that said drive means (1) are able to rotate said transmission means (2), said transmission means (2) being able to rotate said pressure wheel (5), said pressure wheel (5) being able to squeeze said pressure plate (4) by rotation, so that said pressure plate (4) moves towards the side close to said hose (3).

3. Peristaltic pump according to claim 1 or 2, wherein said transmission mechanism (2) comprises a planetary gear (201) and a power take-off shaft (203), said planetary gear (201) being connected at one end to said drive mechanism (1) and at the other end to said power take-off shaft (203), said pressure wheel (5) being connected to said power take-off shaft (203), said pressure wheel (5) being capable of rotating synchronously with said power take-off shaft (203).

4. Peristaltic pump according to claim 1 or 2, characterized in that said hose (3) comprises a hose body (301) and a support plate (302), said support plate (302) being arranged opposite said pressure plate (4).

5. Peristaltic pump according to claim 1, characterized in that said pressure plate (4) is provided with mounting holes (402), said pressure wheel (5) being arranged inside said mounting holes (402).

6. Peristaltic pump according to claim 5, characterized in that a guide slope (402b) is provided in the mounting hole (402), one end of the pressure roller (5) is inserted into the mounting hole (402) and is in contact with the guide slope (402b), when the pressure roller (5) is rotated by the driving mechanism (2), the end of the pressure roller (5) can rotate along the guide slope (402b) and can press the pressure plate (4) through the guide slope (402b), so that the pressure plate (4) moves towards the end close to the hose (3).

7. Peristaltic pump according to claim 6, characterized in that a clamping member (402a) is provided in the mounting hole (402), and correspondingly, a limiting member (502) is provided on the outer surface of the pressing wheel (5), and the clamping member (402a) can be clamped with the limiting member (502) by rotation.

8. Peristaltic pump according to claim 7, characterized in that said snap-in element (402a) is a projection arranged inside said mounting hole (402), and correspondingly said stop element (502) is a projection arranged outside said pressure wheel (5), said snap-in element (402a) and stop element (502) being arranged crosswise.

9. Peristaltic pump according to claim 8, characterized in that the end of the pressure wheel (5) is in contact with the guiding ramp (402b) through the stop (502), the stop (502) being naturally located at the lowest point of the guiding ramp (402 b); when the pressing wheel (5) rotationally presses the pressing plate (4), the limiting piece (502) can rotate to the highest point of the guide inclined plane (402 b).

10. Peristaltic pump according to claim 3, further comprising an elastic member (8), wherein said elastic member (8) is fitted over said power take-off shaft (203), and when said pressure wheel (5) rotates to press said pressure plate (4), said elastic member (8) is compressed by said pressure plate (4); when the peristaltic pump stops working, the elastic piece (8) restores to deform and pushes the pressure plate (4) back to the initial position.

11. Peristaltic pump according to claim 7, characterized in that, before the stop member (502) and the snap member (402a) are rotatably snapped together, the pressure wheel (5) can drive the pressure plate (4) to move towards the side close to the hose (3); after locating part (502) and joint spare (402a) rotatory joint together, pressure disk (4) will follow pinch roller (5) synchronous revolution, just pressure disk (4) can be through rotatory extrusion hose (3) in order to carry liquid.

12. Peristaltic pump according to claim 1, characterized in that the surface of the pressure plate (4) close to the hose (3) is called a pressure contact surface (401), a plurality of hollows (403) are arranged on the pressure plate (4), rollers (404) are arranged in the hollows (403), the rollers (404) are rotatably connected with the pressure plate (4), the rollers (404) protrude from the pressure contact surface (401), and the pressure plate (4) rotatably presses the hose (3) through the rollers (404) to convey liquid.