US20230089643A1

US20230089643A1 - Pump

Info

Publication number: US20230089643A1
Application number: US17/759,819
Authority: US
Inventors: Koji Tanabe; Ryoji HIRAIDE; Hiroshi Nakamoto; Hiroaki Inoue
Original assignee: Aquatech Ltd; I Peace Inc
Current assignee: Aquatech Ltd; I Peace Inc
Priority date: 2020-01-29
Filing date: 2020-01-29
Publication date: 2023-03-23
Also published as: WO2021152749A1; JPWO2021152749A1; JP7168945B2

Abstract

A pump is provided that includes a tube 1, tube rotors 21A, 21B, and 21C in contact with the tube 1, a case 3 containing the tube 1 and tube rotors 21A, 21B, and 21C, and a drive apparatus 10 that rotates the tube rotors 21A, 21B, and 21C from outside the case 3 without contacting the tube rotors 21A, 21B, and 21C.

Description

TECHNICAL FIELD

The present invention relates to a pump.

BACKGROUND ART

Pumps are used for transporting fluids such as liquids and gasses. A pump that makes direct contact with the fluid being transported could contaminate the fluid. Therefore, in cases where contamination of the fluid is not desirable, a tube pump capable of conveying fluid inside a tube without directly contacting the fluid is used (see, for example, Patent Documents 1 and 2). The tube pump includes a rotating part that rotates while compressing the tube. The compressed part of the tube reduces in cross-sectional area. As the compressed part of the tube moves along with the rotation of the rotating part, the fluid inside the tube travels along the rotating direction of the rotating part.

CITATION LIST

Patent Document

Patent Document 1: Japanese Patent No. 4035119
Patent Document 2: Japanese Patent No. 5824685

SUMMARY

Technical Problem

In some cases the pumped fluid inside the tube may contain an infectious substance or a hazardous substance. Therefore, it is preferable to prevent the substance from scattering around the periphery inside the tube in the event of breakage of the tube. Accordingly, an object of the present invention is to provide a pump that eliminates or minimizes the possibility of scattering of the substance in the tube around the periphery in the event of breakage of the tube. Efficient application of a drive force on the fluid traveling inside the tube in the pump is also preferable. Accordingly, another object of the present invention is to provide a pump capable of applying a drive force efficiently on the fluid traveling inside the tube.

Solution to Problem

One aspect of the present invention provides a pump including a tube, a tube rotor in contact with the tube, a case containing the tube and the tube rotor, and a drive apparatus that rotates the tube rotor from outside the case without contacting the tube rotor.
In the above pump, the case may be closed.
In the above pump, the case may have no fluid permeability
In the above pump, the case may have no liquid permeability.
In the above pump, the case may be provided with an inlet connector and an outlet connector, and one end of the tube may be connected to the inlet connector, and another end of the tube may be connected to the outlet connector.
In the above pump, the case may be provided on an inside thereof with a recessed part for accommodating the tube and the tube rotor.
The above pump may further include a magnet connected to the tube rotor, and the drive apparatus may rotate the tube rotor via a magnetic force of the magnet.
In the above pump, the magnet may be provided to the tube rotor.
The above pump may further include a transmission rotor connected to the tube rotor, and the magnet may be provided to the transmission rotor.
The above pump may further include an internal drive rotor connecting the tube rotor and the transmission rotor.
In the above pump, the case may be provided on an inside thereof with a recessed part for accommodating the transmission rotor.
The above pump may further include a light reflector connected to a portion of the tube rotor.
The above pump may further include a light source that projects light to the light reflector from outside the case, and a light receiver that receives reflected light from the light reflector.
The above pump may further include a rotation rate calculator that computes a rotation rate of the tube rotor, based on reflected light received by the light receiver.
In the above pump, a housing part that houses the light source and the light receiver may be provided in an outer wall of the case.
In the above pump, the case and the drive apparatus may be separable.
Another aspect of the present invention provides a pump including a case provided with an annular recessed part, a tube disposed along at least a portion of a side surface of the recessed part of the case, a tube rotor disposed inside the recessed part of the case so as to be able to contact the tube, and an internal drive rotor in contact with the tube rotor, the tube rotor being rotated by a frictional force between the internal drive rotor and the tube rotor, the frictional force being generated when the internal drive rotor rotates.
In the above pump, the tube rotor may rotate around a center of the tube rotor as well as rotate around a center of the internal drive rotor inside the recessed part.
In the above pump, the tube rotor may have a longer radius than a radius of the internal drive rotor.
In the above pump, at a portion of the side surface of the recessed part of the case where the tube is not disposed, the tube rotor may be in contact with the side surface.
In the above pump, a surface of the internal drive rotor in contact with the tube rotor may be rough.

Advantageous Effects of Invention

According to the present invention, a pump that eliminates or minimizes the possibility of scattering of the substance inside the tube in the event of breakage of the tube can be provided. According to the present invention, a pump capable of applying a drive force efficiently on the fluid traveling inside the tube can be provided.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is a diagrammatic perspective view of a pump according to a first embodiment.

FIG. 2 is a diagrammatic exploded perspective view of the pump according to the first embodiment.

FIG. 3 is a diagrammatic perspective view of the pump according to the first embodiment.

FIG. 4 is a diagrammatic cross-sectional view of the pump according to the first embodiment.

FIG. 5 is a diagrammatic perspective view of a pump according to a second embodiment.

FIG. 6 is a diagrammatic perspective view of the pump according to the second embodiment.

FIG. 7 is a diagrammatic side view of the pump according to the second embodiment.

FIG. 8 is a diagrammatic side view of a pump according to a third embodiment.

FIG. 9 is a diagrammatic side view of the pump according to the third embodiment.

FIG. 10 is a diagrammatic side view of the pump according to the third embodiment.

FIG. 11 is a diagrammatic side view of the pump according to the third embodiment.

DESCRIPTION OF EMBODIMENTS

Hereinafter, embodiments of the present invention will be described. Same or like parts depicted in the drawings mentioned below are represented by same or like symbols. The drawings are diagrammatic. Therefore, specific dimensions and the like should be understood in consideration of the following description. It goes without saying that the drawings may contain some parts with different dimensional relationships or ratios from each other.

First Embodiment

The pump according to a first embodiment is a tube pump, and includes, as shown in FIG. 1 to FIG. 4 , a tube 1, tube rotors 21A, 21B, and 21C in contact with the tube 1, a case 3 containing the tube 1 and tube rotors 21A, 21B, and 21C, and a drive apparatus 10 that rotates the tube rotors 21A, 21B, and 21C from outside the case 3 without contacting the tube rotors 21A, 21B, and 21C.
A fluid flows inside the tube 1. In the present disclosure, the fluid includes a gas and a liquid. The tube 1 has flexibility, for example. The material for the tube 1 is selected such that no exchange of gasses, viruses, microbes, impurities, etc., occurs between inside and outside of the tube 1 through the wall of the tube 1. The tube 1 is disposed inside the case 3 such that at least a portion of the tube 1 forms a section of an annular shape.
There is no limitation on the number of tube rotors 21A, 21B, and 21C. The tube rotors 21A, 21B, and 21C each contact a radially inner side of the tube 1 in an annular form and press the tube 1. The tube rotors 21A, 21B, and 21C are each rotatable around the center of the section of the annular shape formed by the tube 1. The tube rotors 21A, 21B, and 21C are also each rotatable inside the case 3 while partially compressing the tube 1. The tube rotors 21A, 21B, and 21C each rotating while partially compressing the tube 1 cause the fluid inside the tube 1 to move along the rotating direction of the tube rotors 21A, 21B, and 21C. Since the tube rotors 21A, 21B, and 21C do not contact the interior of the tube 1, the fluid inside the tube 1 is able to move inside the tube 1 without contacting the tube rotors 21A, 21B, and 21C.
The case 3 is separable into a case 3A and a case 3B, for example. The case 3A and case 3B are able to engage each other, for example. The case 3 is made of a material that has no fluid permeability, for example. Inside the case 3 is provided a recessed part 33 for accommodating the tube 1 and tube rotors 21A, 21B, and 21C, for example. The case 3 is also provided with an inlet connector 31 and an outlet connector 32, for example. One end of the tube 1 is connected to the inlet connector 31, and the other end of the tube 1 is connected to the outlet connector 32. The inlet connector 31 and outlet connector 32 may be integrated with the case 3. Alternatively, the inlet connector 31 and outlet connector 32 may be separable from the case 3. In this case, the inlet connector 31 and outlet connector 32 may be disposed in the case 3 via a sealing member such as an O-ring.
In the case where the case 3A and case 3B are engaged together, with both ends of the tube 1 connected to the inlet connector 31 and outlet connector 32, the interior of the case 3 is shut out from the outside. A vacuum may be drawn inside the closed case 3. The interior of the closed case 3 may be filled with an inert gas such as nitrogen or argon. The interior of the closed case 3 may be filled with a liquid or gel. In the case where the case 3 is shut, any fluid that may be present inside the case 3 cannot come out of the case 3. In the case where the case 3 is shut, any fluid outside the case 3 cannot penetrate into the case 3. Therefore no exchange of gasses, viruses, microbes, impurities, etc., occurs between inside and outside of the case 3.
The pump according to the first embodiment may include magnets 4A, 4B, 4C, and 4D connected to the tube rotors 21A, 21B, and 21C. Any number of magnets may be provided. The drive apparatus 10 disposed outside the case 3A may use the magnetic force of the magnets 4A, 4B, 4C, and 4D to rotate the tube rotors 21A, 21B, and 21C inside the case 3. The magnets may be provided to the tube rotors 21A, 21B, and 21C. Alternatively, the pump according to the first embodiment may include a transmission rotor 5 connected to the tube rotors 21A, 21B, and 21C, with the magnets 4A, 4B, 4C, and 4D being provided to the transmission rotor 5. The magnets 4A, 4B, 4C, and 4D on the transmission rotor 5 are circumferentially equally spaced, for example. The magnets 4A, 4B, 4C, and 4D may be inserted into openings formed in the transmission rotor 5, for example. The transmission rotor 5 may be configured to prevent the magnets 4A, 4B, 4C, and 4D from coming out of the openings formed in the transmission rotor 5. A drive rotor 112 is connected to the center of the transmission rotor 5. The drive rotor 112 is in contact with the tube rotors 21A, 21B, and 21C. In the case where the drive apparatus 10 rotates the transmission rotor 5 via a magnetic force, the drive rotor 112 rotates with the rotating transmission rotor 5, and the tube rotors 21A, 21B, and 21C rotate with the rotating drive rotor 112.
The tube 1 and tube rotors 21A, 21B, and 21C may be disposed inside the case 3A. In this case, the recessed part 33 accommodating the tube 1 and tube rotor 21A, 21B, and 21C is provided to the case 3A. The transmission rotor 5 may be disposed inside the case 3B. A recessed part 34 for accommodating the transmission rotor 5 may be provided to the case 3B. A shaft holding part 6 that holds the drive rotor 112 having a shaft may be disposed inside the case 3. The shaft holding part 6 is disposed between the tube rotors 21A, 21B, and 21C and the transmission rotor 5, for example. The shaft holding part 6 holding the drive rotor 112 keeps the tube rotors 21A, 21B, and 21C, drive rotor 112, and transmission rotor 5 in predetermined positions inside the case 3. Since the recessed part 33 provided in the case 3A can hold the tube rotors 21A, 21B, and 21C, and the recessed part 34 provided in the case 3B can hold the transmission rotor 5, the shaft holding part 6 may be omitted, for example.
The drive apparatus 10 includes a drive shaft 11 and an external drive rotor 12 connected to the drive shaft 11 at the center. Magnets 13A, 13B, 13C, and 13D are provided to the external drive rotor 12. The magnets 13A, 13B, 13C, and 13D on the external drive rotor 12 are circumferentially equally spaced, for example. While any number of magnets may be provided to the external drive rotor 12, it is preferable to provide the same number of magnets to the external drive rotor 12 as the number of magnets connected to the tube rotors 21A, 21B, and 21C. It is also preferable that the magnets on the external drive rotor 12 and the magnets connected to the tube rotors 21A, 21B, and 21C are disposed on a circumference with the same diameter and spaced apart the same. The magnets 13A, 13B, 13C, and 13D provided to the external drive rotor 12 and the magnets 4A, 4B, 4C, and 4D connected to the tube rotors 21A, 21B, and 21C attract each other.
The drive apparatus 10 is disposed outside the case 3. The external drive rotor 12 of the drive apparatus 10 is disposed such that the magnets 13A, 13B, 13C, and 13D of the external drive rotor 12 oppose the magnets 4A, 4B, 4C, and 4D connected to the tube rotors 21A, 21B, and 21C via the case 3. Since the magnets 13A, 13B, 13C, and 13D provided to the external drive rotor 12 and the magnets 4A, 4B, 4C, and 4D connected to the tube rotors 21A, 21B, and 21C attract each other, in the case where the external drive rotor 12 rotates, the tube rotors 21A, 21B, and 21C rotate, too.
The pump according to the first embodiment is capable of rotating the tube rotors 21A, 21B, and 21C encased in the case 3 in a non-contact manner by the drive apparatus 10 disposed outside the case 3. Therefore, in the event of breakage of the tube 1, the substance inside the tube 1 is prevented from scattering out of the case 3. The pump is also capable of preventing an external substance from penetrating into the tube 1 from outside the case 3 and contaminating the fluid inside the tube 1. When transporting pure fluids such as culture liquids, medical liquids, biomolecular liquids, chemical solutions, and so on with the pump, for example, penetration of viruses or bacteria into the liquid inside the tube 1 is prevented. Moreover, when transporting liquids whose pH level should be maintained constant such as culture liquids, medical liquids, biomolecular liquids, chemical solutions, and so on with the pump, for example, changes in pH level of the liquid inside the tube 1 caused by ingress of acidic or basic fluid into the tube 1 is prevented.

Second Embodiment

As shown in FIG. 5 and FIG. 6 , the pump according to a second embodiment includes light reflectors 7A, 7B, and 7C connected to at least one of the tube rotors 21A, 21B, and 21C. The light reflectors 7A, 7B, and 7C reflect light. The light reflectors 7A, 7B, and 7C are circumferentially equally spaced, for example. The light reflectors 7A, 7B, and 7C may be disposed on a tube rotor holder 107 holding the tube rotors 21A, 21B, and 21C. The tube rotor holder 107 is able to rotate with the rotation of the tube rotors 21A, 21B, and 21C. The pump according to the second embodiment further includes a light source that projects light to the light reflectors 7A, 7B, and 7C from outside the case 3, and a light receiver that receives reflected light from the light reflectors 7A, 7B, and 7C. The light receiver converts received reflected light into an electrical signal. The light source and the light receiver may be included in a photo reflector 8.
As shown in FIG. 5 and FIG. 7 , a housing part 35 that houses the light source and the light receiver may be provided in an outer wall of the case. The housing part 35 may be a recess, or a through hole. The light source may project light directly to the light reflectors 7A, 7B, and 7C, or project light to the light reflectors 7A, 7B, and 7C via a reflection mirror. A reflection mirror that refracts the light from the light source may be disposed in the housing part 35. The light receiver may directly receive the reflected light from the light reflectors 7A, 7B, and 7C, or receive the reflected light from the light reflectors 7A, 7B, and 7C via a reflection mirror. A reflection mirror that refracts the reflected light may be disposed in the housing part 35.
In the case where the tube rotors 21A, 21B, and 21C rotate around the center of the section of the annular shape formed by the tube 1, the light reflectors 7A, 7B, and 7C connected to the tube rotors 21A, 21B, and 21C also rotate. If light is emitted from the light source, the light is reflected by the light reflectors 7A, 7B, and 7C that pass the optical axis of the light. The electrical signal generated from the received reflected light by the light receiver is pulsed. The time interval at the light receiver between receptions of reflected light from the light reflectors 7A, 7B, and 7C depends on the rotation rate of the tube rotors 21A, 21B, and 21C around the center of the section of the annular shape formed by the tube 1.
The pump according to the second embodiment may further include a rotation rate calculator that calculates a rotation rate of the tube rotors 21A, 21B, and 21C around the center of the section of the annular shape formed by the tube 1 based on the reflected light received by the light receiver. The rotation rate calculator calculates the rotation rate of the tube rotors 21A, 21B, and 21C around the center of the section of the annular shape formed by the tube 1 based on, for example, a spacing distance between the light reflectors 7A, 7B, and 7C, and a length of a time interval between receptions of reflected light received at the light receiver. The rotation rate calculator may be included in a computer, for example.
Other constituent elements of the pump according to the second embodiment are the same as those of the pump according to the first embodiment, and description thereof will be omitted.
In the case where the tube rotors 21A, 21B, and 21C are rotated in a non-contact manner by the drive apparatus 10 outside the case 3, a situation could arise where the rotation rate of the drive shaft 11 of the drive apparatus 10 does not coincide with the rotation rate of the tube rotors 21A, 21B, and 21C around the center of the section of the annular shape formed by the tube 1. When this is the case, the fluid inside the tube 1 could not be transported at a desired flow rate even if the rotation rate of the drive shaft 11 of the drive apparatus 10 were monitored, because the rotation rate of the tube rotors 21A, 21B, and 21C differs from that of the drive shaft. Since the pump according to the second embodiment is able to accurately detect the rotation rate of the tube rotors 21A, 21B, and 21C, the pump is able to transport the fluid inside the tube 1 at a desired flow rate.

Third Embodiment

As shown in FIG. 8 , the pump according to a third embodiment includes a case 3A provided with an annular recessed part 33, a tube 1 disposed along at least a portion of a side surface of the recessed part 33 of the case 3A, tube rotors 21A, 21B, and 21C disposed inside the recessed part 33 of the case 3A such as to be able to contact the tube 1, and an internal drive rotor 112 in contact with the tube rotors 21A, 21B, and 21C. The internal drive rotor 112 is in a shaft form, for example. In the case where the internal drive rotor 112 in the pump according to the third embodiment rotates, the frictional force between the internal drive rotor 112 and each of the tube rotors 21A, 21B, and 21C causes the tube rotors 21A, 21B, and 21C to rotate.
The tube 1 is configured to allow a fluid to flow inside. The tube rotors 21A, 21B, and 21C are each in a columnar form, for example. Any number of tube rotors may be provided. Respective outer circumferential surfaces of the tube rotors 21A, 21B, and 21C contact a radially inner side of the tube 1 in an annular form and press the tube 1. The internal drive rotor 112 is disposed at the center of the annular recessed part 33. As shown in FIG. 9 , in the case where the internal drive rotor 112 rotates in one direction, the tube rotor 21A rotates around the center of the tube rotor 21A in the opposite direction from the rotating direction of the internal drive rotor 112, and at the same time, the tube rotor 21A rotates inside the recessed part 33 around the internal drive rotor 112 as the center in the same direction as the rotating direction of the internal drive rotor 112. At the portion of the side surface of the recessed part 33 of the case 3A where the tube 1 is not disposed, the tube rotors 21A, 21B, and 21C contact the side surface of the recessed part 33.
The tube rotors 21A, 21B, and 21C each rotating while partially compressing the tube 1 cause the fluid inside the tube 1 to move along the rotating direction of each of the tube rotors 21A, 21B, and 21C around the center of the internal drive rotor 112. Since the tube rotors 21A, 21B, and 21C do not contact the interior of the tube 1, the fluid inside the tube 1 is able to move inside the tube 1 without contacting the tube rotors 21A, 21B, and 21C.
To secure a sufficient frictional force between the internal drive rotor 112 and each of the tube rotors 21A, 21B, and 21C, rough surface of the internal drive rotor 112 making contact with each of the tube rotors 21A, 21B, and 21C may be formed by serration cutting or the like.
The tube rotors 21A, 21B, and 21C may each have a longer radius than the radius of the internal drive rotor 112. Making the radius of each of the tube rotors 21A, 21B, and 21C longer than the radius of the internal drive rotor 112 makes the rotating rate of each of the tube rotors 21A, 21B, and 21C slower than the rotating rate of the internal drive rotor 112. This enables each of the tube rotors 21A, 21B, and 21C to gain a larger torque than that of the internal drive rotor 112.
As shown in FIG. 10 , a recessed part 36 for disposing one end of the tube 1 and a recessed part 37 for disposing the other end of the tube 1 may be connected to the annular recessed part 33. Further, the annular recessed part 33 may be provided with a bearing 51 for the internal drive rotor 112. As shown in FIG. 11 , the tube 1 is disposed in the recessed part 36 and the recessed part 37, and along the side surface of the annular recessed part 33 between the recessed part 36 and the recessed part 37. After setting the tube, the internal drive rotor 112 shown in FIG. 8 may be set in the bearing 51, and further, the tube rotors 21A, 21B, and 21C may be inserted between the internal drive rotor 112 and the tube 1 and between the internal drive rotor 112 and a portion of the side surface of the recessed part 33 where the tube 1 is not disposed.
In the third embodiment, the case 3A may be closed, or not closed. In the case where the case 3A is closed, the case 3B and the transmission rotor 5 shown in FIG. 2 may be provided, and the internal drive rotor 112 may be connected to the center of the transmission rotor 5. This way, the tube rotors 21A, 21B, and 21C encased inside the case 3A and case 3B can be rotated by the drive apparatus 10 from outside the case 3. The configuration of the pump according to the third embodiment may be combined with the configuration of the pump according to the first embodiment in this way. Other configurations such as the light reflector according to the second embodiment may be combined with the configuration of the pump according to the third embodiment.
While the present invention has been described above with reference to some embodiments, the description and drawings that constitute part of this disclosure should not be construed as limiting this invention. Various alternative embodiments, examples, and applicable techniques will become apparent to persons skilled in the art from this disclosure. The present invention should be understood to include various other embodiments and the like that are not described herein.

REFERENCE SIGNS LIST

1 Tube
3 Case
3A Case
3B Case
4A, 4B, 4C, and 4D Magnet
5 Transmission rotor
6 Shaft holding part
7A, 7B, and 7C Light reflector
8 Photo reflector
10 Drive apparatus
11 Drive shaft
12 External drive rotor
13A, 13B, and 13C Magnet
21A, 21B, and 21C Tube rotor
31 Inlet connector
32 Outlet connector
33 Recessed part
34 Recessed part
35 Housing part
36 Recessed part
37 Recessed part
51 Bearing
112 Internal drive rotor

Claims

1. A pump comprising:

a tube;

a tube rotor in contact with the tube;

a case containing the tube and the tube rotor;

a drive apparatus rotating the tube rotor from outside the case without contacting the tube rotor; and

a light reflector disposed on a tube rotor holding member holding the tube rotor.

2. The pump according to claim 1, wherein the case is closed.

3. The pump according to claim 1, wherein the case has no fluid permeability.

4. The pump according to claim 1, wherein the case has no liquid permeability.

5. The pump according to claim 1, wherein

the case is provided with an inlet connector and an outlet connector,

one end of the tube is connected to the inlet connector, and

another end of the tube is connected to the outlet connector.

6. The pump according to claim 1, wherein the case is provided, on an inside thereof, with a recessed part for accommodating the tube and the tube rotor.

7. The pump according to claim 1, further comprising a magnet connected to the tube rotor, wherein

the drive apparatus rotates the tube rotor via a magnetic force of the magnet.

8. The pump according to claim 7, wherein the magnet is provided to the tube rotor.

9. The pump according to claim 7, further comprising a transmission rotor connected to the tube rotor, wherein

the magnet is provided to the transmission rotor.

10. The pump according to claim 9, further comprising an internal drive rotor connecting the tube rotor and the transmission rotor.

11. The pump according to claim 9, wherein the case is provided, on an inside thereof, with a recessed part for accommodating the transmission rotor.

12. (canceled)

13. The pump according to claim 1, further comprising:

a light source that projects light to the light reflector from outside the case; and

a light receiver that receives reflected light from the light reflector.

14. The pump according to claim 13, further comprising a rotation rate calculator that computes a rotation rate of the tube rotor, based on reflected light received by the light receiver.

15. The pump according to claim 13, wherein a housing part that contains the light source and the light receiver is provided in an outer wall of the case.

16. The pump according to claim 1, wherein the case and the drive apparatus are separable.

17. A pump comprising:

a case provided with an annular recessed part;

a tube disposed along at least a portion of a side surface of the recessed part of the case;

a tube rotor disposed inside the recessed part of the case so as to be able to contact the tube; and

an internal drive rotor in contact with the tube rotor, wherein the tube rotor is rotated by a frictional force between the internal drive rotor and the tube rotor, the frictional force being generated in the case where the internal drive rotor rotates,

the pump further comprising a light reflector disposed on a tube rotor holding member holding the tube rotor.

18. The pump according to claim 17, wherein the tube rotor rotates around a center of the tube rotor as well as rotates around a center of the internal drive rotor inside the recessed part.

19. The pump according to claim 17, wherein the tube rotor has a longer radius than a radius of the internal drive rotor.

20. The pump according to claim 17, wherein, at a portion of the side surface of the recessed part of the case where the tube is not disposed, the tube rotor contacts this portion of the side surface of the recessed part.

21. The pump according to claim 17, wherein a surface of the internal drive rotor in contact with the tube rotor is rough.