PERISTALTIC PUMP

FIELD

[0001]The present disclosure relates to a peristaltic pump, for example, a peristaltic pump for fluidic system of a sample processor.

BACKGROUND

[0002]This section only provides background information related to the present disclosure, which is not necessarily a prior art.

[0003]A peristaltic pump is often used in various fluidic systems to continuously convey fluids. The peristaltic pump includes a driver, a pump body and a flexible hose. The flexible hose is fitted in the pump body and used to convey fluid. The driver is attached to the pump body and may drive a roller to repeatedly rotate in one direction (for example, clockwise or counterclockwise direction) and to squeeze the flexible hose while rotating, thereby pumping fluid.

[0004]However, when the peristaltic pump is shut down for a long time, the roller accordingly squeezes the same part of the hose for a long time, resulting in permanent plastic deformation of the squeezed part of the hose. Such plastic deformation may cause reduction of the inner diameter of the peristaltic pump, or even cause adhesion of its inner wall. As a result, when the peristaltic pump is re-activated, the fluid may not be conveyed steadily, and even flow interruption and other faults may occur.

[0005]To solve the above problems, it is known to replace the hose of the peristaltic pump with a new one, which may lead to a significant increase in maintenance costs. Furthermore, it has been proposed to use more flexible materials to make the hose, which may lead to increased product costs. In addition, although more flexible materials can appropriately prolong the service life of the hose, the above problems still exist.

SUMMARY

[0006]A peristaltic pump which can alleviate or avoid the above problems is proposed in the present disclosure. The peristaltic pump according to the present disclosure may avoid or alleviate the squeeze of the hose (especially the same part of the hose) when it is shut down, thereby preventing or mitigating the permanent plastic deformation of the hose.

[0007]According to an aspect of the present application, there is provided a peristaltic pump. The peristaltic pump includes: a frame; a fluid pipe; and a rotor. The fluid pipe is fitted in the frame. The rotor includes a rotary member and a roller. The rotary member is rotatable relative to the frame, and the roller is movable along the fluid pipe for squeezing the fluid pipe to pump fluid in the fluid pipe, when the rotary member is rotated. The roller is connected to the rotary member in such a manner as to allow the roller to move between a first position of squeezing the fluid pipe and a second position of releasing the fluid pipe.

[0008]In some embodiments according to the present application, the rotary member is provided with a groove in which the roller is floatedly received. The groove is configured to allow the roller to move from the second position towards the first position under gravity of the roller and keep the roller in the first position when squeezing the fluid pipe.

[0009]In some embodiments according to the present application, the groove includes a radial section extending in a radial direction and a circumferential section extending in a circumferential direction. The circumferential section is located on a radial outer side of the radial section, where the second position is located at a radial inner end of the radial section, a neutral position is located at where a radical outer end of the radial section and the circumferential section intersect, and the first position is located at a circumferential end of the circumferential section. The groove is configured to allow the roller to move from the second position to the neutral position or from the neutral position to the second position under the gravity of the roller.

[0010]In some embodiments according to the present application, the groove is of an L shape or T shape.

[0011]In some embodiments according to the present application, the rotor is configured to move the roller to the neutral position when the roller returns from downstream to upstream of the fluid pipe.

[0012]In some embodiments according to the present application, the peristaltic pump further includes a bias device configured to move the roller to the neutral position or the first position.

[0013]In some embodiments according to the present application, the bias device includes a permanent magnet or an electromagnetic coil for applying a magnetic force to the roller so as to move the roller towards the neutral position or the first position.

[0014]In some embodiments according to the present application, the bias device includes a first guiding member for pushing the roller so as to move the roller from the second position towards the neutral position.

[0015]In some embodiments according to the present application, the first guiding member has a convex driving surface for pushing the roller in the radial direction.

[0016]In some embodiments according to the present application, the bias device further includes a second guiding member for pushing the roller so as to move the roller from the neutral position towards the first position.

[0017]In some embodiments according to the present application, the second guiding member includes a plectrum and a spring. The spring is configured to exert an elastic force to the plectrum to push the roller.

[0018]In some embodiments according to the present application, the rotor is configured to return the roller to the second position under a friction and the gravity of the roller by rotating the rotary member in a reverse direction or in two opposite directions alternately and repeatedly.

[0019]In some embodiments according to the present application, the peristaltic pump further includes an actuating device configured to drive directly or indirectly the roller relative to the rotary member, so that the roller moves between the first position and the second position.

[0020]In some embodiments according to the present application, the rotary member includes a driving wheel driven by a power source and a driven wheel driven by the driving wheel. The driven wheel is rotatable relative to the driving wheel in a circumferential direction so that the roller moves between the first position and the second position. The roller is provided on one of the driving wheel and the driven wheel; and the actuating device is provided on the other of the driving wheel and the driven wheel.

[0021]In some embodiments according to the present application, the actuating device is provided on the driving wheel, and the roller is provided on the driven wheel.

[0022]In some embodiments according to the present application, the actuating device is a cam.

[0023]In some embodiments according to the present application, the driving wheel includes a first plate and a second plate located at opposite sides of the driven wheel, and a connecting shaft passing through the driven wheel and connecting the first plate and the second plate. The first plate and the second plate are configured as the cam.

[0024]In some embodiments according to the present application, the cam includes protrusions extending from outer circumferential surfaces of the first plate and the second plate.

[0025]In some embodiments according to the present application, the connecting shaft is transmissively connected to an output shaft of the power source.

[0026]In some embodiments according to the present application, the connecting shaft has an end fixed to one of the first plate and the second plate, and the other end drivingly connected to the other of the first plate and the second plate.

[0027]In some embodiments according to the present application, the power source is an electric motor, and a housing of the electric motor is fixed to the frame.

[0028]In some embodiments according to the present application, the frame has an annular recess recessed from an end surface to receive the fluid pipe, and the rotor is located radially inside of the fluid pipe.

[0029]In some embodiments according to the present application, the peristaltic pump further includes a cover plate mounted on the end surface to prevent the fluid pipe and/or the rotor from falling out.

[0030]In some embodiments according to the present application, the driven wheel includes a first plate and a second plate arranged in parallel, and a connection part connecting the first plate and the second plate. The first plate and the second plate each is provided with elongated holes for receiving the roller and enabling movement of the roller.

[0031]In some embodiments according to the present application, the roller includes a pin and a cylindrical member. The pin is inserted into and movable in the elongated holes. The cylindrical member is arranged on the pin and rotatable.

[0032]In some embodiments according to the present application, the elongated holes extend in a radial direction and are symmetrical with respect to the radial direction.

[0033]In some embodiments according to the present application, each of the elongated holes has a section with a constant size or a section with an increased size in a radial outward direction.

[0034]In some embodiments according to the present application, each of the protrusions includes two driving surfaces and an apex converged by the two driving surfaces, and the two driving surfaces are symmetrical with respect to a radial direction passing through the apex.

[0035]In some embodiments according to the present application, each of the protrusions includes a driving surface, a non-driving surface, and an apex converged by the driving surface and the non-driving surface, and an angle formed between the driving surface and a radial direction passing through the apex is greater than an angle formed between the non-driving surface and the radial direction passing through the apex.

[0036]In some embodiments according to the present application, the number of the roller is more than one, the more than one roller is arranged in a circumferential direction, and the protrusions are arranged in the circumferential direction.

[0037]In some embodiments according to the present application, the peristaltic pump further includes a roller bracket on which the roller is rotatably mounted. The roller bracket is connected to the rotary member in such a manner that the roller bracket is movable under drive of the actuating device so that the roller moves between the first position and the second position.

[0038]In some embodiments according to the present application, the peristaltic pump includes multiple rollers and multiple roller brackets for supporting rotatably the multiple rollers respectively. The multiple roller brackets are arranged radially outside the rotary member in a circumferential direction, and are movable radially relative to the rotary member.

[0039]In some embodiments according to the present application, each of the roller brackets is connected to the rotary member through a bar-shaped member.

[0040]In some embodiments according to the present application, the actuating device includes an actuator having a conical outer surface, and each of the roller brackets has an inclined surface in sliding contact with the conical outer surface of the actuator. The actuator is configured to be movable in an axial direction of the rotary member between a release position and a driving position, so that the inclined surface of the roller bracket slides relative to the conical outer surface of the actuator, and so that the roller bracket is radially moved.

[0041]In some embodiments according to the present application, the actuating device further includes a bias member for returning the actuator to the release position.

[0042]In some embodiments according to the present application, the bias member is a spring provided between the actuator and the rotary member. The actuator and/or the rotary member is provided with a recess for receiving the spring.

[0043]In some embodiments according to the present application, the actuating device further includes a drive mechanism configured to drive the actuator, and the drive mechanism includes a mechanical drive mechanism or an electromagnetic drive mechanism.

[0044]In some embodiments according to the present application, the drive mechanism is a mechanical drive mechanism including one of: a screw and a nut; a worm and a gear; and an eccentric wheel or a cam.

[0045]The above and other objects, features and advantages of the present disclosure will be more fully understood from the detailed description given below and the accompanying drawings, which are given by way of illustration only and therefore are not considered to limit the present disclosure.

BRIEF DESCRIPTION OF THE DRAWINGS

[0046]The features and advantages of one or more embodiments of the present disclosure will become more readily understood from the following description with reference to the accompanying drawings. In the drawings:

[0047]FIG. 1 is a schematic perspective view of a peristaltic pump according to a first embodiment of the present disclosure;

[0048]FIG. 2 is a schematic exploded view of the peristaltic pump of FIG. 1;

[0049]FIG. 3 is a schematic cross-sectional view of the peristaltic pump of FIG. 1, cut along the front-rear direction;

[0050]FIG. 4 is a schematic front view of a rotor of the peristaltic pump of FIG. 1;

[0051]FIG. 5 is a schematic perspective view of a driven wheel of the rotor of FIG. 4;

[0052]FIG. 6 is a schematic front view of the driven wheel of FIG. 5, in which a roller is removed;

[0053]FIG. 7 is a schematic front view of a first plate of a driving wheel of the rotor of FIG. 4;

[0054]FIG. 8 is a schematic front view of a variant of the driven wheel of FIG. 6;

[0055]FIGS. 9A and 9B show the force condition of the roller supported on the first plate of the driven wheel of FIGS. 6 and 8, respectively;

[0056]FIG. 10 is a schematic front view of a variant of the first plate of the driving wheel of FIG. 7;

[0057]FIG. 11 is a schematic perspective view of a peristaltic pump according to a second embodiment of the present application;

[0058]FIG. 12 is a schematic exploded view of the peristaltic pump of FIG. 11;

[0059]FIG. 13 is a schematic perspective view of a rotor of the peristaltic pump of FIG. 11;

[0060]FIG. 14 is a schematic enlarged view of one groove of the rotor of FIG. 13;

[0061]FIGS. 15A to 15F are schematic views of the operation process of the peristaltic pump of FIG. 11;

[0062]FIG. 16 is a schematic view of the peristaltic pump of FIG. 11 having a bias device according to a first embodiment of the present application;

[0063]FIGS. 17A to 17C are schematic perspective view, a schematic front view, and a partially enlarged schematic view, respectively, of the peristaltic pump of FIG. 11 having a bias device according to a second embodiment of the present application;

[0064]FIG. 18 is a schematic view of a peristaltic pump according to a third embodiment of the present application;

[0065]FIGS. 19A and 19B are schematic views of the peristaltic pump of FIG. 18 having a drive mechanism according to a first embodiment of the present application and showing the process of moving the roller to an operating position and returning the roller to a release position, respectively;

[0066]FIG. 20 is a schematic view of the peristaltic pump of FIG. 18 having a drive mechanism according to a second embodiment of the present application; and

[0067]FIG. 21 is a schematic view of the peristaltic pump of FIG. 18 having a drive mechanism according to a third embodiment of the present application.

DETAILED DESCRIPTION OF THE EMBODIMENTS

[0068]Exemplary embodiments of the present application will now be described more comprehensively with reference to the accompanying drawings. It should be understood that in all these figures, the same reference numerals indicate similar or corresponding parts or features. In addition, the drawings are not necessarily drawn to actual scale, and some parts may be shown in an enlarged scale for the convenience of illustration.

[0069]The following detailed description of the present application is for purposes of illustration only and is in no way limiting of the present application, its application or uses. The embodiments described in this specification are not exhaustive and are merely some of many possible embodiments. Exemplary embodiments may be embodied in many different forms and should not be construed as limitation to the scope of the present application. In some exemplary embodiments, well-known processes, well-known device structures, and well-known technologies may not be described in detail.

[0070]A peristaltic pump 10 according to a first embodiment of the present application will be described below with reference to FIGS. 1 to 7.

[0071]FIG. 1 is a schematic perspective view of a peristaltic pump 10 according to a first embodiment of the present application; FIG. 2 is a schematic exploded view of the peristaltic pump 10; and FIG. 3 is a schematic cross-sectional view of the peristaltic pump 10 cut along the front-rear direction. As shown in FIGS. 1 to 3, the peristaltic pump 10 includes a frame 11, a fluid pipe 13, a rotor 15 and a power source 19. The fluid pipe 13 is fitted in the frame 11. The power source 19 provides power for the rotor 15 to rotate. The rotor 15 squeezes the fluid pipe 13 while rotating, so that the fluid in the fluid pipe 13 flows under the thrust of the rotor 15, thereby conveying the fluid.

[0072]The frame 11 forms the pump body of the peristaltic pump 10, and is used to hold, mount or support other parts of the peristaltic pump 10. In the example shown, the frame 11 is generally in a form of rectangular parallelepiped, having a front end surface 11a, a rear end surface 11b, and four side surfaces 11c located between the front end surface 11a and the rear end surface 11b.

[0073]An annular recess 11d recessed from the front end surface 11a is provided on the front end surface 11a of the frame 11. The fluid pipe 13 is accommodated in the annular recess 11d. The frame 11 may be further provided with two linear grooves 11e extending from the annular recess 11d to the side surface 11c. One of the linear grooves 11e is used to accommodate an input end 13a of the fluid pipe 13, while the other of the linear grooves 11e is used to accommodate an output end 13b of the fluid pipe 13. The input end 13a and the output end 13b of the fluid pipe 13 can be connected to a pipeline (not shown) of a fluidic system to which the peristaltic pump 10 is applied. It should be understood that, the “input end” and “output end” are named according to the flow direction of the fluid, so they can be interchanged with the reverse flow of the fluid.

[0074]The fluid pipe 13 is a flexible pipe, for example, a hose. When the fluid pipe 13 is pressed by the rotor 15, the pressed part of the fluid pipe 13 is deformed and the flow area is reduced. When the fluid pipe 13 is no longer pressed by the rotor 15, the pressed part of the fluid pipe 13 may return from deformation. The fluid pipe 13 is located between the rotor 15 and the frame 11, so that the rotor 15 can press the fluid pipe 13 against the frame 11 (specifically, the wall defining the annular recess 11d).

[0075]The power source 19 is located at a rear end surface 11b of the frame 11. The frame 11 and the power source 19 may be connected together by inserting or engaging fasteners 12 such as screws into holes of the frame 11 and holes of a housing 19a of the power source 19. It should be understood that, the power source 19 may be attached to the frame 11 in any suitable way, and should not be limited to the example shown.

[0076]The power source 19 includes an output shaft 19b. The frame 11 includes a through hole 11f for the output shaft 19b to pass through, so that the output shaft 19b can be drivingly coupled to the rotor 15. The power source 19 may be an electric motor, for example. It should be understood that the power source 19 can be any suitable device or equipment capable of driving the rotor 15.

[0077]The rotor 15 is configured to be rotatable and can squeeze the fluid pipe 13 while rotating. In the example shown, the rotor 15 is located at a radially inner side of the fluid pipe 13 and presses the fluid pipe 13 toward an inner peripheral wall of the frame 11 defining the annular recess 11d.

[0078]As shown, the rotor 15 includes a rotary member 102 and a roller 140 movably mounted on the rotary member 102. The rotary member 102 is rotatable relative to the frame 11 when driven by the power source 19. The roller 140 is movable along a fluid pipe 13, as the rotary member 102 is rotated. When the peristaltic pump 10 runs to convey the fluid, the roller 140 is moved to an operating position (also referred to as a first position) that squeezes the fluid pipe 13 and moves along the fluid pipe 13 from an input end 13a of the fluid pipe 13, thereby conveying the fluid in the fluid pipe 13. When the roller 140 reaches an output end 13b of the fluid pipe 13, the roller 140 continues to move in a circumferential direction to the input end 13a, and the process of moving, squeezing and conveying the fluid as described above are repeated to continuously conveying the fluid. When the peristaltic pump 10 stops and no longer conveys the fluid, the roller 140 is moved to a release position (also referred to as a second position) that releases (i.e., does not squeeze) the fluid pipe 13, thereby avoiding permanent plastic deformation of the fluid pipe 13.

[0079]The rotary member 102 includes a driving wheel 110 and a driven wheel 120. The driving wheel 110 is coupled to the output shaft 19b of the power source 19 and is driven by the outer shaft 19b to rotate. In addition, the driving wheel 110 can drive and rotate the driven wheel 120. The relative rotation of the driving wheel 110 and the driven wheel 120 enables the roller 140 to move between the operating position and the release position.

[0080]The peristaltic pump 10 further includes an actuating device 16. In the peristaltic pump 10 according to the first embodiment, the actuating device 16 is in the form of a cam 130. The cam 130 is configured such that, as the driving wheel 110 drives the driven wheel 120 to rotate, the cam drives or pushes the roll 140 to move until the roller 140 moves to the operating position where the fluid pipe 13 is pressed to convey the fluid. At this time, the roller 140 does not move any more, and the driving wheel 110 and the driven wheel 120 keep rotating synchronously, so that the peristaltic pump 10 can normally convey the fluid. When the peristaltic pump 10 stops, that is, when the driving wheel 110 is no longer driven by the power source 19, the cam 130 no longer exerts a pushing force on the roller 140. In this way, the fluid pipe 13 returns under its own flexibility to the release position or the initial position where the fluid pipe 13 is partially or completely released. Therefore, even if the peristaltic pump 10 is stopped for a long time, the fluid pipe 13 will not be permanently plastically deformed by long-term squeeze.

[0081]In the example shown, the driving wheel 110 includes the cam 130, and the roller 140 is movably supported on the driven wheel 120. It should be understood that the rotor according to the present application should not be limited to the specific example shown. For example, the cam 130 may be provided on the driven wheel 120, and the roller 140 may be movably provided on the driving wheel.

[0082]Referring to FIGS. 2, 3 and 7, the driving wheel 110 includes a first plate 110a, a second plate 110b and a connecting shaft 110c. The first plate 110a and the second plate 110b are located on two sides of the driven wheel 120 respectively and are both configured to push the roller 140 to move. Therefore, the first plate 110a and the second plate 110b constitute the above-mentioned cam 130. With this configuration, the roller 140 can be stably moved. The connecting shaft 110c passes through the driven wheel 120 and connects the first plate 110a and the second plate 110b. The connecting shaft 110c is further coupled to the power source 19 to transmit power to the driving wheel 110.

[0083]The connecting shaft 110c has a through hole 1101 for receiving the output shaft 19b of the power source 19. The connecting shaft 110c may be drivingly coupled to the output shaft 19b of the power source 19, for example, by a key (not shown). It should be understood that the connecting shaft 110c can be connected to the power source 19 in any other known suitable way, and it is not necessarily limited to the specific example shown.

[0084]One end of the connecting shaft 110c may be fixed to the second plate 110b located at the inner side. Referring to FIG. 3, the connecting shaft 110c is integrally formed with the second plate 110b. It should be understood that the connecting shaft 110c and the second plate 110b can be separately formed and fixedly connected together. The other end of the connecting shaft 110c is drivingly coupled to the first plate 110a located at the outer side.

[0085]An outer circumferential surface of the connecting shaft 110c includes a first section 1103 and a second section 1105. The first section 1103 is configured to engage with the first plate 110a to transmit power. The first plate 110a has a through hole 1113 for receiving the first section 1103. The first section 1103 and the through hole 1113 may have shapes that are engaged and matched with each other to transmit power. In the example shown, both the through hole 1113 and the first section 1103 have a flat surface and an arc-shaped surface, whereby torque can be transmitted. Through the engagement of the first section 1103 and the through hole 1113, power is transmitted from the connecting shaft 110c to the first plate 110a. In this way, the first plate 110a and the second plate 110b can rotate synchronously. A cover plate 17 may be provided on the front end surface 11a of the frame 11, thereby preventing the first plate 110a and/or the fluid pipe 13 from falling off. The cover plate 17 may be mounted to the frame 11 by fasteners 14 such as screws.

[0086]The second section 1105 of the connecting shaft 110c is configured to support the driven wheel 120 and allow the relative rotation between the driving wheel 110 and the driven wheel 120. In other words, the driven wheel 120 is rotatably supported on the second section 1105 of the connecting shaft 110c. The driven wheel 120 has a through hole 1215 for receiving the second section 1105. The second section 1105 and the through hole 1215 may have a cylindrical shape as shown, or may have any other suitable shape as long as the function mentioned herein can be achieved.

[0087]The first plate 110a and the second plate 110b each have protrusions 150 extending from their outer circumferential surface to drive the roller 140. The number of protrusions 150 is the same as the number of rollers 140, which is six in the example shown. It should be understood that the number of protrusions 150 and rollers 140 is not limited to six as shown in the figures, but may be more or less.

[0088]The protrusions 150 of the first plate 110a and the second plate 110b have the same structure. Therefore, the following description will be given by taking the first plate 110a as an example. FIG. 7 is a schematic front view of the first plate 110a. As shown in FIG. 7, each protrusion 150 includes two driving surfaces 111 and 112 and an apex 113 converged by the two driving surfaces 111 and 112. In the example shown in FIG. 7, the two driving surfaces 111 and 112 are symmetrical about the radial direction (RD) passing through the apex 113. This structure allows the rotor 15 to rotate clockwise and counterclockwise. If the rotor 15 rotates clockwise, the driving surface 112 is used to drive the roller 140 to move. If the rotor 15 rotates counterclockwise, the driving surface 111 is used to drive the roller 140 to move.

[0089]It should be understood that the structure of the protrusion should not be limited to the specific example shown, as long as it can realize the functions described herein. For example, FIG. 10 shows a variant of the first plate 110a of the driving wheel 110, the variant having different structure of the protrusion. The first plate 210a shown in FIG. 10 has multiple protrusions 250. The protrusion 250 includes a driving surface 211, a non-driving surface 212, and an apex 213 converged by the driving surface 211 and the non-driving surface 212. The driving surface 211 and the non-driving surface 212 are arranged asymmetrically with respect to the radial direction RD passing through the apex 213. As shown in FIG. 10, the angle formed between the driving surface 211 and the radial direction RD is larger than the included angle between the non-driving surface 212 and the radial direction RD. That is, the driving surface 211 has a more moderate slope than the non-driving surface 212, so as to facilitate moving the roller 140 from the radially inner release position or initial position to the radially outer operating position.

[0090]The driving surface is linear in the example shown. However, it shall be noted that the driving surface shall not be limited to the example shown, and may be curved, as long as the function mentioned herein can be achieved.

[0091]Referring to FIGS. 2, 3, 5 and 6, the driven wheel 120 includes a first plate 121 and a second plate 122 arranged in parallel, and a connection part 123 connecting the first plate 121 and the second plate 122. As shown in FIG. 3, the first plate 121, the second plate 122 and the connection part 123 are integrated. It should be understood that the first plate 121, the second plate 122 and the connection part 123 can be formed separately and then fixedly connected together.

[0092]The first plate 121 and the second plate 122 are respectively provided with elongated holes 125 and 126 for receiving the roller 140 and enabling movement of the roller 140. The elongated holes 125 and 126 have the same structure. Referring to FIG. 6, the elongated holes 125 extend in a radial direction and are symmetrical with respect to the radial direction. With this structure, the roller 140 moves substantially in the radial direction.

[0093]It should be understood that the structure of the elongated holes should not be limited to the specific example shown, as long as it can realize the functions described herein. For example, FIG. 8 shows a variant of the first plate 121 of the driven wheel 120, the variant having a different structure of the elongated holes. The first plate 221 shown in FIG. 8 has multiple elongated holes 225. Each of the elongated holes 225 has a section with gradually increasing size in the radial outward direction. Compared with the elongated hole 225 shown in FIG. 8, the elongated hole 125 shown in FIG. 6 has a section with a substantially constant size.

[0094]FIGS. 9A and 9B show the force condition of the rollers supported on the first plates of the driven wheels of FIGS. 6 and 8, respectively. In FIGS. 9A and 9B, F denotes the force exerted by the protrusion 150 on the roller 140, and F1 and F2 denote component forces for pushing the roller 140 to move, and θ1 and θ2 denote the angles formed between the component forces F1 and F2 and the force F, respectively. Compared with the elongated hole 125 of FIG. 9A, the size of the elongated hole 225 of FIG. 9B gradually increases in the radial outward direction, that is, the elongated hole is generally triangular in shape. As such, the angle θ2 formed between the component force F2 and the force F is smaller than the angle θ1 formed between the component force F1 and the force F. Given the same force F, the component force F2 is greater than the component force F1. Therefore, the elongated hole 225 of FIG. 9B is more useful for movement of the roller 140, or can reduce the driving power of the power source 19.

[0095]It should be understood that the structure of the protrusion and/or the elongated hole can be changed as required, and should not be limited to the specific example shown in the figures.

[0096]Returning back to FIG. 5, the roller140 may include a pin 141 and a cylindrical member 142. The pin 141 is inserted into the elongated holes 125 and 126 and is movable in the elongated holes 125 and 126 in the radial direction. When the pin 141 abuts against the radially inner side walls of the elongated holes 125 and 126, the roller 140 is in the release position or the initial position. When the pin 141 abuts against the radially outer side walls of the elongated holes 125 and 126, the roller 140 is in the operating position. The cylindrical member 142 is rotatably provided on the pin 141. The roller 140 can press the fluid pipe 13 via the cylindrical member 142, thereby significantly reducing the friction between the cylindrical member 142 and the fluid pipe 13. The pin 141 may have a head 1411 at one end thereof. When the pin 141 is inserted into the elongated holes 125 and 126, the head 1411 abuts against the outside face of the driven wheel 120 so as to position the pin 141. The roller 140 may further include a retaining ring 143 for fixedly connecting to the other end of the pin 141. The pin 141 is held in the elongated holes 125 and 126 by the head 1411 and the retaining ring 143.

[0097]It should be understood that the number and structure of the rollers 140 can be changed as desired, and should not be limited to the specific examples shown in the figures.

[0098]A peristaltic pump 20 according to a second embodiment of the present application will be described below with reference to FIGS. 11 to 17C.

[0099]Referring to FIGS. 11 to 13, the peristaltic pump 20 includes a frame 21, a fluid pipe (not shown), a rotor 25, and a power source 29. The structure of the frame 21 and the power source 29 of the peristaltic pump 20 is substantially the same as the structure of the frame 11 and the power source 19 of the peristaltic pump 10, and therefore will not be described in detail. The difference between the peristaltic pump 20 and the peristaltic pump 10 described above lies in a different structure of the rotor. The rotor 25 of the peristaltic pump 20 will be described in detail below.

[0100]The rotor 25 includes a rotary member 202 and a roller 240 movably mounted on the rotary member 202. The rotary member 202 is engaged with an output shaft 29b of a power source 29 and is rotatable relative to the frame 21 when driven by the power source 29.

[0101]The rotary member 202 includes a first plate 202a, a second plate 202b, and a connecting shaft 202c. The first plate 202a and the second plate 202b are located on two sides of the roller 240 respectively. With this configuration, the roller 240 can be stably supported. The first plate 202a and the second plate 202b are fixedly connected with each other through the connecting shaft 202c. The connecting shaft 202c is further coupled to the output shaft 29b of the power source 29 to transfer power to the rotary member 202.

[0102]The first plate 202a and the second plate 202b each is provided with grooves 230 for receiving the rollers 240 and allowing the rollers 240 to move. The grooves 230 have the same structure. FIG. 14 is an enlarged schematic view of one groove 230 of the rotor 202 of the peristaltic pump 20.

[0103]As shown in FIG. 14, the groove 230 has a substantially T-shaped shape including a radial section 230a extending in a radial direction and a circumferential section 230b extending in a circumferential direction. The circumferential section 230b is located on a radial outer side of the radial section 230a. Operating positions P11 and P12 at which the roller 240 squeezes the fluid pipe for transporting the fluid are defined at a circumferential end of the circumferential section 230b. The operating positions P11 and P12 are determined according to the direction of rotation of the rotor 25. When the rotor 25 rotates in a counterclockwise direction, the roller 240 is located at the operating position P11. When the rotor 25 rotates in the clockwise direction, the roller 240 is located at the operating position P12. A release position P2 where the roller 240 releases the fluid pipe to prevent permanent plastic deformation of the fluid pipe is defined at the radial inner end of the radial section 230a. In addition, a neutral position PO is defined where the radial outer end of the radial section 230a and the circumferential section 230b intersect. The neutral position PO is located between the operating position P11 or P12 and the release position P2, and facilitates switching of the roller 240 between the operating position P11 or P12 and the release position P2.

[0104]The roller 240 is floatingly received in the groove 230. The groove 230 is constructed or shaped to allow the roller 240 to move from the release position P2 to the neutral position PO or from the neutral position PO to the release position P2 under the gravity of the roller 240.

[0105]The operation of the peristaltic pump 20 will be described below with reference to FIGS. 15A to 15F. The peristaltic pump 20 includes six pairs of grooves 231 to 236 formed in the first plate 202a and the second plate 202b and six rollers 241 to 246 floatingly supported in the six pairs of grooves 231 to 236, respectively. As mentioned above, the number, arrangement and configuration of the rollers can change as required and are not necessarily limited to the specific examples shown in the figures.

[0106]Referring to FIG. 15A, the peristaltic pump 20 is in a non-operational state. The first roller 241 is supported in the first pair of grooves 231 and is located between the input end 13a and the output end 13b of the fluid pipe 13. At this time, the first roller 241 is at the neutral position. The second roller 242 to the sixth roller 246 are distributed along the length of the fluid pipe 13. The second roller 242 to the sixth roller 246 are supported in the second pair of grooves 232 to the sixth pair of grooves 236, respectively, and are all located at the release position of releasing the fluid pipe. It can be seen that when the peristaltic pump 20 is not operating, none of the rollers 241 to 246 exert pressure on the fluid pipe 13, in other words, the fluid pipe 13 is not plastically deformed.

[0107]When the peristaltic pump 20 is operating, the rotor 202 is caused to rotate, for example, in a counterclockwise direction. The rotor 202 is rotated to be in a state as shown in FIG. 15B.

[0108]Referring to FIG. 15B, the first roller 241 moves counterclockwise to an operating position in the grooves 231. The first roller 241 moves towards the circumferential end of the circumferential section of the grooves 231 under the gravity of the first roller 241 and the friction of the fluid pipe 13 when the first roller 241 rotates, until the first roller 241 reaches the operating position. At the operating position, the first roller 241 squeezes the fluid pipe 13, thereby driving fluid within the fluid pipe 13 to flow. The second roller 242 moves to the neutral position as the first roller 241 shown in FIG. 15A, and movement from the release position to the neutral position is helpful to enter the operating state. The third roller 243 to the sixth roller 246 remain in the release position and are not involved in fluid conveying.

[0109]When the rotor 202 is rotated to the state shown in FIG. 15C, the first roller 241 remains at the operating position and conveys fluid along the length of the fluid pipe 13. The second roller 242 enters the fluid conveying state as the first roller 241 shown in FIG. 15B. By analogy, a roller follows the action and state of the preceding roller, as shown in FIGS. 15D to 15F. Thereafter, the roller moves from the neutral position to the operating position for conveying fluid and remains in the operating position as the roller begins to squeeze the fluid pipe 13 and moves along the length of the fluid pipe 13, and returns to the neutral position as the roller returns from the output end 13b to the input end 13a of the fluid pipe 13.

[0110]In FIG. 15F, the process of the first roller 241 squeezing the fluid pipe 13 ends. At this moment the first roller 241 may either be in the operating position of squeezing the fluid or may fall towards the other end of the grooves 231 under the gravity, depending on the forces applied to the first roller 241.

[0111]When the operation of the peristaltic pump 20 ends, all of the rollers are returned to a state as shown in FIG. 15A. For example, the rotor 202 is rotated in the reverse direction (e.g., in a clockwise direction), the roller moves towards the neutral position under the friction. When the roller moves to the neutral position, the roller is brought back down from the neutral position to the release position at which the fluid pipe is not squeezed under the gravity of the rollers. The rotor 202 can be rotated several times repeatedly in the clockwise and counterclockwise directions so that all of the rollers are in the release position or the neutral position, as shown in FIG. 15A.

[0112]As described above, when the peristaltic pump 20 operates to convey fluid, the roller 240 is moved to the operating position of squeezing the fluid pipe 13 and moves along the fluid pipe 13 from the input end 13a of the fluid pipe 13, thereby conveying the fluid in the fluid pipe 13. When the roller 240 reaches the output end 13b of the fluid pipe 13, the roller 240 is moved to the non-operating position and returned to the neutral position, and the process of moving, squeezing and conveying fluid as described above are repeated, to continuously conveying the fluid. When the peristaltic pump 20 stops operating and no longer conveys the fluid, the roller 240 is moved to neutral position or a release position of releasing (i.e., not squeezing) the fluid pipe 13, thereby avoiding permanent plastic deformation of the fluid pipe 13.

[0113]It should be understood that the configuration of the peristaltic pump 20 and its various portions should not be limited to the specific examples shown, and can be varied as long as it can perform the functions described herein. For example, if the peristaltic pump rotates in only one direction, the groove may be L-shaped. For example, a bias device that drives the roller to the neutral position or the operating position may be provided to prevent the roller from becoming stuck in the release position and not being able to conveying the fluid.

[0114]FIG. 16 shows a schematic view of a peristaltic pump 20 having a bias device 260 according to a first embodiment of the present application. As shown in FIG. 16, the bias device 260 is provided between the input end 13a and the output end 13b of the fluid pipe 13 and is configured to apply a downward magnetic force to the roller 240, thereby causing the roller 240 to move toward the neutral position or the operating position. The bias device 260 may be a permanent magnet or an electromagnetic coil. It should be understood that the type or configuration of the bias device 260 should not be limited to the specific example shown in FIG. 16, but may be varied as long as it can perform the functions described herein.

[0115]FIGS. 17A to 17C show a schematic perspective view, a schematic front view, and a partially enlarged schematic view, respectively, of the peristaltic pump 20 having a bias device 270 according to a second embodiment of the present application. The bias device 270 mechanically moves the roller from the second position to the neutral position and/or from the neutral position to the operating position.

[0116]As shown in FIGS. 17A to 17C, the bias device 270 may include a first guiding member 271 and a second guiding member 281. The first guiding member 271 is configured to push the roller 240 to move the roller 240 from the release position toward the neutral position. The second guiding member 281 is configured to push the roller 240 to move the roller 240 from the neutral position toward the operating position.

[0117]The first guiding member 271 is fixed to the frame 21. The first guiding member 271 has a convex driving surface 273 that pushes the roller 240 in a radial direction. The roller 240 is subjected to a radially outward thrust force as the roller 240 moves along the convex driving surface 273, thereby moving towards the neutral position. It should be understood that the configuration and arrangement of the first guiding member 271 should not be limited to the specific examples shown in FIGS. 17A and 17B, but may be varied as long as it can perform the functions described herein.

[0118]FIG. 17C is a partially enlarged schematic view of the second guiding member 281. Referring to FIG. 17C, the second guiding member 281 may include a plectrum 282 and a spring 283. The spring 283 is configured to exert an elastic force to the plectrum 282 such that the plectrum 282 abuts against the roller 240. The plectrum 282 is configured to be able to apply a force to the roller 240 that causes the roller 240 to move toward the operating position. It should be understood that the configuration and arrangement of the second guiding member 281 should not be limited to the specific examples shown in FIGS. 17A to 17C, but may be varied as long as it can perform the functions described herein.

[0119]A peristaltic pump 30 according to a third embodiment of the present application will be described below with reference to FIGS. 18 to 21.

[0120]Referring to FIG. 18, the peristaltic pump 30 includes a rotor 35. The frame, the fluid pipe, and the power source are omitted in FIG. 18. The differences between the peristaltic pump 30 and the peristaltic pumps 10 and 20 described above primarily lie in the structure of the rotor and the mechanism that drives the movement of the roller.

[0121]The rotor 35 includes a rotary member 302, a roller bracket 320, and a roller 340 mounted on the roller bracket 320. The rotary member 302 is engaged with a power source (not shown in FIG. 18) and is rotatable relative to the frame when driven by the power source. The roller bracket 320 together with the roller 340 rotates as the rotary member 302 is rotated. Additionally, the roller bracket 320 is movably coupled to the rotary member 302. In this way, the roller bracket 320 together with the roller 340 moves, so that the roller 340 is movable between an operating position of squeezing the fluid pipe and a release position of releasing the fluid pipe. To reduce wear, the roller 340 is rotatably mounted on the roller bracket 320.

[0122]The peristaltic pump 30 may include multiple rollers 340 and multiple roller brackets 320 for supporting rotatably the multiple rollers 340 respectively. The multiple roller brackets 320 are arranged radially outside the rotary member 302 in a circumferential direction and are movable radially relative to the rotary member 302. Each roller bracket 320 may be connected to the rotary member 302 through a bar-shaped member 330.

[0123]The rotor 35 further includes an actuating device 36. The actuating device 36 is configured to move the roller brackets 320 relative to the rotary member 302 and therefore move the rollers 340 between an operating position and a release position.

[0124]The actuating device 36 may include an actuator 36a having a conical outer surface 362. Accordingly, the roller bracket 320 has an inclined surface 322 in sliding contact with the conical outer surface 362 of the actuator 36a. When the conical outer surface 362 slides (to the right in FIG. 18), the conical outer surface 362 pushes the inclined surface 322, so that the inclined surface 322 moves radially outward to the operating position of squeezing the fluid pipe. When the conical outer surface 362 slides in the opposite direction (to the left in FIG. 18), the thrust force of the conical outer surface 362 on the inclined surface 322 disappears, and the roller bracket 320 together with the roller 340 can return to the release position of releasing the fluid pipe.

[0125]In the example shown in FIG. 18, movement of the actuator 36a along the axial direction of the rotary member 302 is converted into radial movement of the roller bracket 320 and the roller 340 by relative sliding between the conical outer surface 362 and the inclined surface 322. Preferably, the actuator 36a may not only move along the axial direction of the rotary member 302, but may also rotate with the roller bracket 320 (or may rotate with both the roller bracket 320 and the rotary member 302). In this way, wear of the actuator 36a relative to the roller bracket 320 (and the rotary member 302) can be reduced.

[0126]The actuating device 36 may further include a bias member 36b for returning the actuator 36a to the release position. For example, the bias member 36b may be a spring provided between the actuator 36a and the rotary member 302. The actuator 36a and/or the rotary member 302 may be provided with a recess for receiving the spring. In the example shown in FIG. 18, only the actuator 36a is provided with a recess for receiving the spring.

[0127]The actuating device 36 may further include a drive mechanism (not shown in FIG. 18) configured to drive the actuator 36a. Examples of the drive mechanism are illustrated in FIGS. 19A to 21.

[0128]FIGS. 19A and 19B are schematic views of a peristaltic pump 30 having a drive mechanism 370 according to a first embodiment of the present application. The drive mechanism 370 drives the movement of actuator 36a by the relative sliding between inclined surfaces (similar to the sliding between the conical outer surface 362 and the inclined surface 322).

[0129]Referring to FIGS. 19A and 19B, the drive mechanism 370 includes a drive member 37a having a conical outer surface 373. Accordingly, the actuator 36a has a conical or inclined surface 363 in sliding contact with the conical outer surface 373. The drive member 37a moving upwardly causes the actuator 36a to slide to the right, thereby causing the roller bracket 320 and the roller 340 to move radially outward to the operating position. Conversely, the drive member 37a moving downwards causes the actuator 36a to slide to the left under the action of the bias member 36b, thereby releasing the roller bracket 320 and the roller 340 and thereby releasing the fluid pipe.

[0130]Preferably, the drive member 37a is not only movable upward or downward, but also rotatable. As such, wear of the drive member 37a with respect to the actuator 36a can be reduced.

[0131]The mechanism configured to move the drive member 37a upward or downward is not limited in the present application, but rather can have many variants, as long as it can perform the functions described herein. For example, the mechanism such as a cam, an eccentric wheel, a worm and a gear, a screw and a nut, and the like can be used to move the drive member 37a or directly move the actuator 36a.

[0132]FIG. 20 is a schematic view of a peristaltic pump 30 having a drive mechanism 380 according to a second embodiment of the present application. The drive mechanism 380 is configured to directly push the actuator 36a to move the actuator 36a.

[0133]Referring to FIG. 20, the drive mechanism 380 includes a push member 381 that abuts against the actuator 36a and pushes the actuator 36a. The drive mechanism 380 includes a device 382 for moving the push member 381. For example, the device 382 may drive the push member 381 by using either the principles of a worm and a gear or the principles of a screw and a nut.

[0134]The mechanism for moving the push member 381 is not limited in the present application, and can have many variants, as long as it can perform the functions described herein.

[0135]FIG. 21 is a schematic view of a peristaltic pump 30 having a drive mechanism 390 according to a third embodiment of the present application. The drive mechanism 390 moves the actuator 36a by using magnetic or electromagnetic properties. As shown in FIG. 21, the drive mechanism 390 may include a magnet or an electromagnetic coil 391. As the magnet or the electromagnetic coil 391 applies a magnetic force to the actuator 36a, the actuator 36a moves horizontally, thereby causing the roller bracket 320 to move along with the roller 340.

[0136]It should be understood that the configuration of the peristaltic pump 30 and its various portions should not be limited to the specific examples shown, but may be varied as long as it can perform the functions described herein.

[0137]The peristaltic pump according to the present disclosure can be applied to various fluidic systems, for example, the fluidic system of a sample processor for detecting or sorting liquid samples containing biological particles (e.g., extracellular vesicles) or non-biological particles (e.g., beads).

[0138]Although the present application has been described with reference to exemplary embodiments, it should be understood that the present application is not limited to the specific embodiments described in detail and illustrated herein. Without departing from the scope defined by the appended claims, those skilled in the art can make various changes to the exemplary embodiments. Provided that there is no contradiction, the features in the various embodiments can be combined with each other. Alternatively, a certain feature, such as the cover plate, in the embodiment may be omitted.