A squeeze-type peristaltic pump

Abstract

This specification discloses an extrusion-type peristaltic pump comprising a main body, a transmission component, a pressing unit, and a limit plate. The transmission component and the pressing unit are disposed within the main body, the limit plate is fixedly connected to the main body, and a hose is positioned between the pressing unit and the limit plate. The pressing unit, driven by the transmission component, reciprocates to compress the hose. The pressing unit comprises at least two extrusion members of different structures. This solution utilizes the pressing unit to compress the hose, reducing friction between the hose and the extrusion component, minimizing fatigue damage to the hose, and increasing the hose's lifespan.

Description

Technical Field

[0001] The present application relates to the technical field of peristaltic pumps, and in particular to an extrusion-type peristaltic pump. Background Art

[0002] The most common peristaltic pumps currently in use are those that use a rotating roller to squeeze a flexible tube to deliver fluid. This is like pinching a fluid-filled hose with your fingers; as your fingers slide forward, the fluid moves forward. Peristaltic pumps operate on the same principle, but with rollers replacing the fingers. Fluid is pumped by alternately squeezing and releasing the pump's flexible delivery hose. Summary of the Invention

[0003] To solve the above technical problems, the embodiments of this specification are implemented as follows:

[0004] An embodiment of the present specification provides an extrusion-type peristaltic pump, comprising: a main body, a transmission component, a pressing unit and a limiting plate, wherein the transmission component and the pressing unit are arranged inside the main body, the limiting plate is fixedly connected to the main body, a hose is placed between the pressing unit and the limiting plate, the pressing unit performs reciprocating motion under the drive of the transmission component, and is used to press the hose, and the pressing unit comprises at least two extrusion parts with different structures.

[0005] Optionally, the transmission component includes a camshaft, a ball slide group, an upper wedge block and a lower wedge block; the upper wedge block and the lower wedge block form a rolling fit on the wedge surface, the lower wedge block is fixedly connected to the upper plate of the ball slide group, the lower plate of the ball slide group is connected to the main body, the lower wedge block is arranged in the radial direction of the camshaft, and the rotation of the camshaft drives the lower wedge block to move horizontally, and then drives the upper wedge block to move up and down, and the upper wedge block is fixedly connected to the pressing unit.

[0006] Optionally, one end of the limiting plate is hinged to the body via a pin, and the other end of the limiting plate is detachably connected to the body via a bolt.

[0007] Optionally, the pressing unit includes a liquid inlet cut-off block, a working pressure block and a liquid discharge cut-off block arranged in sequence along the axial direction of the hose, the liquid inlet cut-off block and the working pressure block have different shapes, and the camshaft includes a liquid inlet cut-off cam, an extrusion cam and a liquid discharge cut-off cam in sequence along the liquid transmission direction, the liquid inlet cut-off cam is used to drive the liquid inlet cut-off block to perform reciprocating motion, the liquid discharge cut-off cam is used to drive the liquid discharge cut-off block to perform reciprocating motion, and the extrusion cam is used to drive the working pressure block to perform reciprocating motion.

[0008] Optionally, the upper wedge block and the lower wedge block form a wedge block group, and the wedge block group consists of three pieces, which are respectively arranged corresponding to the liquid inlet cut-off cam, the extrusion cam and the liquid discharge cut-off cam.

[0009] Optionally, there are two hoses, and the two hoses are arranged side by side along the axial direction of the camshaft. The camshaft includes: a liquid inlet cut-off cam 1, a liquid inlet cut-off cam 2, a pressing cam, a liquid discharge cut-off cam 1 and a liquid discharge cut-off cam 2. The liquid inlet cut-off cam 1, the pressing cam and the liquid discharge cut-off cam 1 indirectly act on the hose 1, and the liquid inlet cut-off cam 2, the pressing cam and the liquid discharge cut-off cam 2 indirectly act on the hose 2.

[0010] Optionally, the first liquid inlet cut-off cam, the second liquid inlet cut-off cam, the pressing cam, the first liquid discharge cut-off cam and the second liquid discharge cut-off cam are arranged in sequence.

[0011] Optionally, there is a gap between any adjacent cams on the camshaft.

[0012] Optionally, the upper wedge block is fixedly connected to the pressing unit via a linear guide shaft, and the linear guide shaft is connected to the body via a linear bearing.

[0013] Optionally, it further includes: a mounting plate, which is arranged between the upper wedge block and the pressing unit, and the mounting plate is fixedly connected to the body.

[0014] Optionally, it further includes: a return spring, which is arranged between the upper wedge block and the mounting plate and is sleeved on the linear guide shaft.

[0015] At least one of the above technical solutions adopted in the embodiments of this specification can achieve the following beneficial effects:

[0016] This solution uses a pressing unit to press the hose, which reduces the friction between the hose and the extrusion component, reduces fatigue damage to the hose, and increases the service life of the hose.

[0017] In addition, the extrusion peristaltic pump will also produce pulsation when transmitting fluid. In order to reduce pulsation and achieve stable fluid transmission, this solution uses two parallel elastic hoses to compensate each other for alternate suction and discharge of liquid, so that the pulsation of the total pipeline after confluence is small, and continuous and stable fluid transmission is achieved. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] The drawings described herein are used to provide a further understanding of the present application and constitute a part of the present application. The illustrative embodiments of the present application and their descriptions are used to explain the present application and do not constitute an improper limitation on the present application. In the drawings:

[0019] Figure 1A schematic diagram of the three-dimensional structure of an extrusion-type peristaltic pump provided in an embodiment of this specification;

[0020] Figure 2 for Figure 1 Schematic diagram of the internal structure without the shell;

[0021] Figure 3 for Figure 1 Schematic diagram of the three-dimensional structure with the middle limit plate opened;

[0022] Figure 4 is a schematic diagram of the transmission structure;

[0023] Figure 5 This is a schematic diagram of the connection between two hose outlets in an extrusion peristaltic pump;

[0024] Figure 6 for Figure 1 Schematic diagram of two hose inlets and outlets being connected;

[0025] Among them, in the figure: 1. Motor; 101. Liquid inlet cut-off cam 1; 103. Liquid inlet cut-off cam 2; 104. Pressing cam; 105. Liquid discharge cut-off cam 1; 106. Liquid discharge cut-off cam 2; 107. Camshaft (drive shaft); 2. Limiting mechanism; 201. Pin; 202. Limiting plate bracket; 203. Limiting plate; 204. Bolt; 3. Hose 1; 4. Hose 2; 5. Main body; 6. Mounting plate; 7. Ball slide group; 8. Lower wedge block; 9. Upper wedge block; 10. Bearing; 11. Return spring; 12. Linear guide shaft; 13. Linear bearing; 14. Liquid discharge cut-off block 2; 15. Working pressure block 2; 16. Liquid inlet cut-off block 2; 17. Liquid discharge cut-off block 1; 18. Working pressure block 1; 19. Liquid inlet cut-off block 1; 20. Main pipe liquid suction port; 21. Main pipe liquid discharge port. DETAILED DESCRIPTION

[0026] To make the purpose, technical solutions, and advantages of this application more clear, the technical solutions of this application will be clearly and completely described below in conjunction with the specific embodiments of this application and the corresponding drawings. Obviously, the embodiments described are only part of the embodiments of this application, not all of them. Based on the embodiments in this application, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of this application.

[0027] The present invention proposes a method of installing a variable-direction wedge mechanism, which drives two pressing units arranged on both sides after changing their directions through the wedge mechanism, and arranges the limit plate, pipeline and pressing unit on the same side, thereby saving the limit plate structure on one side.

[0028] The present invention makes the limiting plate into a flip cover structure, and the two hoses can be loaded and unloaded by operating the limiting plate once. Since the operation only needs to be performed on one side, the operating space requirement of the working environment is reduced.

[0029] Each pressing component uses two sets of linear shafts and linear bearings for reciprocating motion to ensure that the pressing component can press the pipeline stably and accurately, making the fluid transmission stable and accurate.

[0030] An embodiment of the present specification provides an extrusion-type peristaltic pump, comprising: a main body, a transmission component, a pressing unit and a limiting plate, wherein the transmission component and the pressing unit are arranged inside the main body, the limiting plate is fixedly connected to the main body, a hose is placed between the pressing unit and the limiting plate, the pressing unit performs reciprocating motion under the drive of the transmission component, and is used to press the hose, and the pressing unit comprises at least two extrusion parts with different structures.

[0031] It should be noted that the reciprocating motion is not specifically limited and can be a linear reciprocating motion or a swinging reciprocating motion, as long as the hose can be pressed and the fluid can be transmitted.

[0032] The main body refers to the integral part of the extrusion peristaltic pump, and other structures are all structurally installed based on the main body. The main body here can also be called a shell, a frame, or other names. Among them, the shell inside the main body is empty, and it can be a shell without a cover on the top, or without a cover on the top and the bottom. In this embodiment, the transmission component and the pressing unit can be arranged inside the main body. When there are multiple transmission components and multiple pressing units, there can also be multiple main bodies, and one transmission component and one pressing unit can be arranged inside one main body, or the main body can be one, and multiple transmission components and multiple pressing units can be arranged inside one main body.

[0033] The pressing unit can be a single component or a combination of multiple components. It can be understood as the part, component, or element that presses the hose. Compared to traditional rotary peristaltic pumps, the intermittent action of the pressing unit reduces axial friction on the hose, thereby reducing excessive axial friction on the hose, thereby improving the hose's service life and transmission accuracy.

[0034] It should be noted that, in this solution, one hose can be provided to form a single-channel peristaltic pump, or two or more hoses can be provided to form a dual-channel or multi-channel peristaltic pump.

[0035] Furthermore, the pressing unit includes at least two extrusion members of different structures. It is understood that these multiple extrusion members can be arranged together or separately, and there is no connection between the multiple extrusion members. For example, the pressing unit may include a working pressure block and a hose shut-off block (a liquid inlet shut-off block and a liquid discharge shut-off block). The working pressure block and the hose shut-off block may use different drive components and transmission components and have no connection between them.

[0036] The working pressure block may include two or more sub-pressure blocks, and the hose cut-off block may include multiple sub-cut-off blocks. This can reduce the occurrence of problems such as jamming.

[0037] The stop plate, also known as a fixing block, fixing plate, or upper pressure block, is used to limit the position of the hose. It secures the hose between the stop plate and the pressure unit. The stop plate functions similarly to the upper pressure block of a rotary peristaltic pump. There can be multiple stop plates, one for each of the inlet stop block, working pressure block, and discharge stop block.

[0038] The transmission component is used to drive the pressing unit to press the hose, wherein the transmission component can be an eccentric transmission mechanism such as a cam, a connecting rod mechanism, a linear transmission mechanism, etc. The transmission component and the pressing unit can be in point contact, line contact, or surface contact.

[0039] In the above-described embodiment, the eccentric transmission mechanism may include multiple eccentric components. An eccentric component can be understood as a component whose geometric center and mass center (center of gravity) are not the same point. The eccentric transmission mechanism may include an eccentric wheel and a cam. The eccentric wheel primarily refers to a circular wheel whose center and rotation center are not aligned. The cam may refer to a mechanical rotating or sliding member (such as a wheel or a protruding portion of a wheel) that transmits motion to a roller moving close to its edge or a needle bar moving freely on a groove surface, or receives force from such a roller or needle bar. Based on the cam profile, the follower can obtain any desired motion pattern, and the structure is simple, compact, and easy to manufacture.

[0040] In some embodiments, the eccentric transmission mechanism is a camshaft having a plurality of cams, the camshaft is rotatably disposed on the body, and the phase angles corresponding to the highest peaks of adjacent cams are different.

[0041] In these embodiments, the eccentric transmission mechanisms all utilize cam structures to jointly drive different pressing units to achieve different functions. The peaks of adjacent cams correspond to different phase angles, which can be understood as differences in the central angle positions corresponding to the peaks of the cams. For example, when one cam is in a closed position with respect to a hose, the adjacent cam cannot be in a closed position with respect to the hose, i.e., the peaks of the adjacent cams correspond to different phase angles.

[0042] The phase angle can be understood as placing the origin of the X, Y two-dimensional coordinates at the center of the cam spindle. The angle between the positive direction of the X axis and the direction of movement of the cam follower is the phase angle. It is used when calculating the relative rotation angle of the cam profile with respect to the camshaft keyway when calculating the origin of movement.

[0043] The phase angles corresponding to the highest peaks of the multiple cams are different so that when the pressing unit is driven to press the hose, the functions of the several structures of the pressing unit can be distinguished to jointly realize different processes, such as liquid intake, transmission and discharge.

[0044] By integrating cams with different functions on the same shaft and driving them by a single motor, the squeeze-type peristaltic pump has a high degree of integration and reduces structural complexity.

[0045] In addition, it should be noted that adjacent cams may be in close contact or may be spaced a certain distance apart from each other.

[0046] The following describes in detail the technical solutions provided by various embodiments of the present application in conjunction with the accompanying drawings.

[0047] like Figure 1-4 As shown, the extrusion peristaltic pump provided in this embodiment includes: a motor 1, a limit plate 203, a body 5, a transmission component and a pressing unit. The transmission component and the pressing unit are arranged inside the body 5, and the hose is arranged between the pressing unit and the limit plate 203.

[0048] like Figure 2 As shown, the transmission components include a camshaft, a ball slide group 7, an upper wedge block 9 and a lower wedge block 8; the upper wedge block 9 and the lower wedge block 8 form a rolling fit on the wedge surface, the lower wedge block 8 is fixedly connected to the upper plate of the ball slide group 7, the lower plate of the ball slide group 7 is connected to the body 5, the lower wedge block 8 is arranged in the radial direction of the camshaft, and the rotation of the camshaft drives the lower wedge block 8 to move horizontally, thereby driving the upper wedge block 9 to move up and down, and the upper wedge block 9 is fixedly connected to the pressing unit.

[0049] Specifically, a mounting plate 6 is fixedly mounted on the lower end of the body 5, and the lower plate of the roller slide group 7 is connected to the mounting plate 6. The mounting plate 6 is arranged between the upper wedge block 9 and the pressing unit.

[0050] The upper wedge block 9 and the lower wedge block 8 form a wedge block group, which is set to three. The three wedge modules correspond to the liquid inlet stop valve, the working pressure block, and the liquid discharge stop valve. Among them, the liquid inlet stop cam, the squeeze cam, and the liquid discharge stop cam control the liquid inlet stop valve, the working pressure block, and the liquid discharge stop valve respectively.

[0051] Among them, the liquid inlet stop valve, working pressure block and discharge stop valve are divided into two groups, namely: the first group: discharge stop block 17, working pressure block 18 and liquid inlet stop block 19, which directly act on hose 3; the second group: discharge stop block 2 14, working pressure block 2 15 and liquid inlet stop block 2 16, which directly act on hose 2.

[0052] The liquid inlet cut-off cam 101, the liquid inlet cut-off cam 2 103, the pressing cam 104, the liquid discharge cut-off cam 1 105 and the liquid discharge cut-off cam 2 106, the liquid inlet cut-off cam 101, the pressing cam 104, the liquid discharge cut-off cam 1 105 indirectly act on the hose 1 3, and the liquid inlet cut-off cam 2 103, the pressing cam 104, the liquid discharge cut-off cam 2 106 indirectly act on the hose 2 4.

[0053] The upper wedge block 9 is fixedly connected to the pressing unit via a linear guide shaft 12 , and the linear guide shaft 12 is connected to the body 5 via a linear bearing 13 .

[0054] In addition, it also includes: a return spring 11, which is arranged between the upper wedge block 9 and the mounting plate 6 and is sleeved on the linear guide shaft 12.

[0055] There are three on one side of the camshaft and three on the other side, which can be used as a dual-channel peristaltic pump head.

[0056] Optionally, one end of the limiting plate is hinged to the body via a pin, and the other end of the limiting plate is detachably connected to the body via a bolt.

[0057] like Figure 2 As shown, the limiting mechanism 2 includes a pin 201, a limiting plate bracket 202, a limiting plate 203 and a bolt 204; wherein the limiting plate 203 adopts a flip cover structure:

[0058] The limit plate 203 and the limit plate bracket 202 are connected with bolts and then hinged to the pump body through the pin 201. The limit plate 203 rotates around the pin 201 to realize the opening and closing action. After the limit plate 203 is closed, the locking bolt 204 is fastened to the corresponding threaded hole of the body 5 to ensure that the limit plate 203 is reliably limited.

[0059] In which, the pressing unit includes a liquid inlet cut-off block, a working pressure block and a liquid discharge cut-off block arranged in sequence along the axial direction of the hose, the liquid inlet cut-off block and the working pressure block have different shapes, and the camshaft includes a liquid inlet cut-off cam, an extrusion cam and a liquid discharge cut-off cam in sequence along the liquid transmission direction, the liquid inlet cut-off cam is used to drive the liquid inlet cut-off block to perform reciprocating motion, the liquid discharge cut-off cam is used to drive the liquid discharge cut-off block to perform reciprocating motion, and the extrusion cam is used to drive the working pressure block to perform reciprocating motion.

[0060] In addition, there are two hoses, which are arranged side by side along the axial direction of the camshaft. The camshaft includes: a liquid inlet cutoff cam 101, a liquid inlet cutoff cam 103, a pressing cam 104, a liquid discharge cutoff cam 105, and a liquid discharge cutoff cam 106. The liquid inlet cutoff cam 101, the pressing cam 104, and the liquid discharge cutoff cam 105 indirectly act on the hose 13, while the liquid inlet cutoff cam 103, the pressing cam 104, and the liquid discharge cutoff cam 106 indirectly act on the hose 24. The liquid inlet cutoff cam 101, the liquid inlet cutoff cam 103, the pressing cam 104, the liquid discharge cutoff cam 105, and the liquid discharge cutoff cam 106 are arranged in sequence.

[0061] Optionally, there is a gap between any adjacent cams on the camshaft.

[0062] like Figure 4 As shown, the main transmission structure is as follows:

[0063] Camshaft 107 is connected to motor 1. Camshaft 107 is sequentially mounted with liquid inlet cutoff cam 101, liquid inlet cutoff cam 2 103, pressure cam 104, liquid discharge cutoff cam 105, and liquid discharge cutoff cam 2 106. Six lower wedge blocks 8 are arranged at corresponding positions on the cams and are mounted on mounting plate 6 via ball slides 7. The lower plate of the ball slide is fixed to mounting plate 6 with screws, and the upper plate of the ball slide 7 is fixed to the lower wedge blocks 8 with screws. Bearings 10 are mounted on the wedge surface of the upper wedge block 9. The upper and lower wedge blocks 9 and 8 form a rolling fit through the bearings 10 to reduce friction. Two linear guide shafts 12 are mounted on the upper end surface of the upper wedge block 9. The two linear guide shafts 12 are mated with linear bearings 13.

[0064] The action flow is as follows:

[0065] As motor 1 rotates, camshaft 107 and its mounted liquid inlet cutoff cams 101, 103, pressure cam 104, discharge cutoff cam 105, and 106 simultaneously rotate. Six lower wedge blocks 8, mounted on mounting plate 6, are driven by the contours of each cam, performing horizontal reciprocating motion via ball bearings 7. To improve cam transmission accuracy, the present invention employs a method in which each cam independently drives the corresponding lower wedge block 8. Simultaneously, lower wedge block 8 drives upper wedge block 9, which then undergoes a 90-degree turn and undergoes vertical reciprocating motion. This motion is guided by two linear guide shafts 12 and linear bearings 13 mounted on the upper end faces of upper wedge block 9.

[0066] In addition, the specific driving process of the cam group:

[0067] The cam group is divided into two groups, which respectively drive the two pressing components to alternately press the two parallel hoses; the liquid inlet cut-off cam 101, the pressing cam 104, and the liquid discharge cut-off cam 105 are one group, and the liquid inlet cut-off cam 103, the pressing cam 104, and the liquid discharge cut-off cam 106 are another group. The pressing cam 104 uses the contour lines of different positions of the same cam to drive the two working pressure blocks to work.

[0068] As camshaft 107 rotates, drain cutoff cam 105 first drives drain cutoff block 17 to compress hose 13. Simultaneously, inlet cutoff cam 103 drives inlet cutoff block 16 to compress hose 24. Then, inlet cutoff cam 101 drives inlet cutoff block 19 to release hose 13, and pressing cam 104 drives working pressure block 18 to release hose 13, completing the process of hose 3 absorbing liquid. Simultaneously, drain cutoff cam 106 drives drain cutoff block 214 to release hose 24, and pressing cam 104 drives working pressure block 215 to compress hose 24, completing the process of hose 24 draining liquid. The alternating action of working pressure block 18 and working pressure block 215 ensures that hose 13 and hose 24 compensate for each other. When hose 13 absorbs liquid, hose 24 discharges it; when hose 13 drains it, hose 24 absorbs it, ensuring the continuous flow of liquid from hoses 13 and 24 to the main pipe.

[0069] 4) Advantages of using two sets of cams to drive separately:

[0070] Each cam independently drives the stop valve pressure block, which can ensure that when hose 3 absorbs liquid, the discharge stop block 17 presses hose 3 tightly, and the inlet stop block 19 releases hose 3; when hose 3 discharges liquid, the inlet stop block 19 presses hose 3 tightly, and the discharge stop block 17 releases hose 3, so that the liquid can only be transported forward.

[0071] The same applies to hose 2 and 4.

[0072] The extrusion peristaltic pump will also produce pulsation when transmitting fluid. In order to reduce pulsation and achieve stable fluid transmission, this solution uses two parallel elastic hoses to compensate each other for alternate suction and discharge, so that the pulsation of the total pipeline after the junction is small, and continuous and stable fluid transmission is achieved. Figure 5 As shown, the discharge ports of hose 1 3 and hose 2 4 are connected, or Figure 6 As shown, the liquid suction port and liquid discharge port of hose 1 3 and hose 2 4 are connected to form a main pipe liquid suction port 20 and a main pipe liquid discharge port 21.

[0073] (1) Cam arrangement: Two sets of front and rear stop valve cams are used to drive the stop valve pressure blocks for the two hoses, which can ensure that each stop valve pressure block can press the hose to achieve the stop valve function; using one pressing cam to drive two identical working pressure blocks can ensure that the discharge volume of the two pipelines is consistent.

[0074] (2) The wedge-shaped mechanism is used to achieve direction change, and the two hoses are arranged on one side of the pump body. The loading and unloading of the two hoses can be completed in one operation, and the operating space in the working environment is saved.

[0075] The foregoing is merely an embodiment of the present application and is not intended to limit the present application. For those skilled in the art, the present application may have various changes and variations. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present application should all be included within the scope of the claims of the present application.

Claims

1. A squeeze-type peristaltic pump, characterized in that: include: A body, a transmission component, a pressing unit, and a limiting plate, wherein the transmission component and the pressing unit are disposed inside the body, the limiting plate is fixedly connected to the body, a hose is placed between the pressing unit and the limiting plate, the pressing unit reciprocates under the drive of the transmission component to press the hose, and the pressing unit includes at least two extrusion members with different structures; The transmission component includes a camshaft, a ball sliding group, an upper wedge block and a lower wedge block; the upper wedge block and the lower wedge block form a rolling fit on the wedge surface, the lower wedge block is fixedly connected to the upper plate of the ball sliding group, the lower plate of the ball sliding group is connected to the body, the lower wedge block is arranged in the radial direction of the camshaft, and the rotation of the camshaft drives the lower wedge block to move horizontally, thereby driving the upper wedge block to move up and down, and the upper wedge block is fixedly connected to the pressing unit; The pressing unit includes a liquid inlet cut-off block, a working pressure block and a liquid discharge cut-off block arranged in sequence along the axial direction of the hose. The liquid inlet cut-off block and the working pressure block have different shapes. The camshaft includes a liquid inlet cut-off cam, an extrusion cam and a liquid discharge cut-off cam in sequence along the liquid transmission direction. The liquid inlet cut-off cam is used to drive the liquid inlet cut-off block to reciprocate, the liquid discharge cut-off cam is used to drive the liquid discharge cut-off block to reciprocate, and the extrusion cam is used to drive the working pressure block to reciprocate; The upper wedge block and the lower wedge block form a wedge block group, and the wedge block group consists of three wedge blocks, which are respectively arranged corresponding to the liquid inlet cut-off cam, the extrusion cam and the liquid discharge cut-off cam; There are two hoses, which are arranged side by side along the axial direction of the camshaft. The camshaft includes: a first liquid inlet cut-off cam, a second liquid inlet cut-off cam, a pressing cam, a first liquid discharge cut-off cam and a second liquid discharge cut-off cam. The first liquid inlet cut-off cam, the pressing cam and the first liquid discharge cut-off cam indirectly act on the first hose, and the second liquid inlet cut-off cam, the pressing cam and the second liquid discharge cut-off cam indirectly act on the second hose.

2. The squeeze-type peristaltic pump according to claim 1, wherein: One end of the limiting plate is hinged to the body through a pin shaft, and the other end of the limiting plate is detachably connected to the body through a bolt.

3. The squeeze-type peristaltic pump according to claim 1, wherein: The first liquid inlet cut-off cam, the second liquid inlet cut-off cam, the pressing cam, the first liquid discharge cut-off cam and the second liquid discharge cut-off cam are arranged in sequence.

4. The squeeze-type peristaltic pump according to claim 1, wherein: There is a gap between any adjacent cams on the camshaft.

5. The squeeze-type peristaltic pump according to claim 1, wherein: The upper wedge block is fixedly connected to the pressing unit via a linear guide shaft, and the linear guide shaft is connected to the body via a linear bearing.

6. The squeeze-type peristaltic pump according to claim 5, characterized in that: Also includes: A mounting plate is provided between the upper wedge block and the pressing unit, and the mounting plate is fixedly connected to the body.

7. The squeeze-type peristaltic pump according to claim 6, characterized in that: Also includes: A return spring is arranged between the upper wedge block and the mounting plate and is sleeved on the linear guide shaft.

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