JP2003074462A - Magnetic fluid pump - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a magnetic fluid pump capable of surely realizing reduction of weight and size to stably secure intended force-feed and controllability of a liquid and causing no problem in use in the artificial heart while solving the problem of heat generation and entering of foreign matter such as dust by using a magnetic fluid (lump) instead of a solid valve. SOLUTION: A rotor and a rotary cylinder in which permanent magnets are arranged so that a plurality of confronting magnetic poles different in phase face to each other are provided on the central side and outside of a cylindrical pressure generating part formed by two or more-turns spiral pipe having an inlet and a discharge port at both end parts. The rotor and rotary cylinder are simultaneously rotated, whereby a magnetic fluid in the spiral pipe is attracted between the magnetic poles of the rotor and the rotary cylinder to form a magnetic fluid lump, and an intended liquid is clamped between the front and rear magnetic fluid lumps and spirally moved in rotation to be discharge.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a small pump for medical use such as an artificial heart and other industrial pumps, and a magnetic fluid is used as a working fluid instead of a pressure generating portion using a solid valve as in a conventional pump. Is a pump having a pressure generating section based on a new principle, and more specifically, a magnetic fluid capable of fluid pressure control, in which the magnetic fluid is moved by the rotation of magnetic poles, and the target fluid is pumped using this magnetic fluid as a working fluid. It is about pumps.

[0002]

2. Description of the Related Art In a conventional pump, a valve portion is driven by a motor or the like, a fluid is sent out by the operation of the valve, and pressure is also generated. Since these pumps have moving parts inside, heat may be generated by the moving parts and bearings, and foreign matter such as dust generated by friction and wear due to the operation of the moving parts may get mixed into the fluid. is there.
In addition, the movable part is often formed of an iron material and the like, and the weight of the pump becomes considerable, so that it cannot be used as, for example, a pump for an artificial heart.

On the other hand, Japanese Patent Application Laid-Open No. 11-13649 proposes a pump using a magnetic fluid. This pump has a first magnetic pole composed of a rotating cylindrical body in which a plurality of recesses are formed in parallel with each other on the outer circumference in parallel and at equal intervals, and a second magnetic pole arranged on the main body side in a passage formed by a second magnetic pole. Fill the magnetic fluid, apply a magnetic field to the magnetic fluid, and
It is a pump configured to send out the magnetic fluid attracted between the magnetic poles by rotationally driving the first magnetic pole, for example, for supplying the magnetic fluid to the actuator as a working fluid. This pump can solve some of the drawbacks of the conventional pump having a solid valve, but since it has a structure in which only the first magnetic pole is rotated, the pump is sufficiently lightweight and compact. I can't answer. Further, this pump is intended to supply the magnetic fluid itself and has a problem that it cannot be used as a pump for supplying a liquid other than the magnetic fluid, for example, blood, medicine, water or the like.

[0004]

DISCLOSURE OF THE INVENTION According to the present invention, it is possible to more reliably realize weight reduction and downsizing while solving the problems of heat generation and the inclusion of foreign matter such as dust, and to supply the target liquid more stably. The present invention also provides a magnetic fluid pump that uses a magnetic fluid as a working fluid, which is not a problem even when used as an artificial heart.

[0005]

SUMMARY OF THE INVENTION According to the present invention, a plurality of relative parts are provided on the central side and the outer side of a cylindrical pressure generating portion formed by a spiral pipe having two or more turns having an inlet and an outlet at both ends. The rotor and the rotary cylinder, in which the (permanent) magnets are arranged so that the magnetic poles of different phases face each other, and the rotor and the drive device for the rotary cylinder are provided, and the rotor and the rotary cylinder are simultaneously rotated to form a spiral shape. The magnetic fluid taken in the pipe is attracted between the rotor and the magnetic poles of the rotating cylinder to move in a spiral shape, and the target liquid is sandwiched between the magnetic fluid masses formed before and after the magnetic fluid mass to be discharged in a spiral shape. It is a magnetic fluid pump characterized in that it is configured to. In this magnetic fluid pump, a magnetic fluid circulation path communicating with the suction port side via a magnetic separation device for separating the magnetic fluid is connected to the discharge port side,
The magnetic fluid is separated from the target liquid on the discharge port side and circulated to the suction port side, whereby it is possible to more reliably prevent the magnetic fluid from mixing with the target liquid. Further, it is possible to reduce the magnetic fluid cost by reducing the amount of magnetic fluid used.

[0006]

BEST MODE FOR CARRYING OUT THE INVENTION The magnetic fluid pump of the present invention uses a magnetic fluid mass as a valve, and is described in the above-mentioned JP-A-11-.
Although it utilizes the basic principle common to the pumps described in Japanese Patent No. 13649, it can also be used as a small pump pump for medical purposes in which a magnetic fluid is used as a working fluid, for example, a target liquid such as blood, medicine, or water is to be pumped. The pump has an applicable unique structure, and its purpose and structure are basically different from those of the pump described in Japanese Patent Laid-Open No. 11-13649, and the method of fluid pressure control is also different. That is, the magnetic fluid pump of the present invention includes a rotor in which (permanent) magnets are arranged such that a plurality of opposing magnetic poles of different phases face each other outside the central portion of a cylindrical pressure generating portion formed of a spiral pipe. A rotary cylinder is provided to rotate the rotor and the rotary cylinder at the same time.The magnetic fluid in the spiral pipe is attracted between the rotor and the magnetic poles of the rotary cylinder to move spirally. The target liquid is sandwiched between the magnetic fluid mass before and after it is formed, and is spirally moved and ejected. In this magnetic fluid pump, in particular, due to the effect of the spiral pipe and the simultaneous rotation of the rotor and the rotary cylinder, the pump can be made more compact and lighter in weight, and the pumping control performance is also excellent. In addition, since a solid valve is not used, the problems of heat generation and foreign matter mixing are solved, and the above problems when applied to a small pump such as a pump for an artificial heart can be solved. Can offer a completely new and innovative small pump.

The magnetic fluid that flows in the spiral pipe of the pressure generating portion is a dispersion of ferromagnetic ultrafine particles in a solvent solution. This solvent solution is used for water, blood, etc. Select one that does not dissolve in the liquid. This magnetic fluid temporarily mixes with the target liquid in the spiral pipe forming the pressure generating portion, but the magnetic fluid is separated by the magnetic separation device arranged on the discharge port side of the pump, and then again. By flowing to the suction port side of the pump and circulating it as a magnetic fluid, the magnetic fluid cost can be reduced, and the characteristics of the magnetic fluid itself and the characteristics of the target liquid are not impaired. The spiral pipe forming the pressure generating portion is preferably made of a lightweight material which is a non-magnetic material, and the number of turns of the spiral is 2 so that the length of the pipe in the magnet arrangement region can be increased to enhance the discharge force. It is preferable that the number of windings is at least one. The larger the number of windings, the more the ejection force increases, but if the number of windings increases, it will go against size reduction.
It will be selected in consideration of the pipe diameter, pumping conditions, downsizing of the device, and the like.

The magnets arranged on the rotor and the rotary cylinder are:
A permanent magnet that has a simple structure and is compact and lightweight is preferable. This magnet rotates the rotor and the rotary cylinder at the same time, attracts the magnetic fluid in the spiral pipe between the magnetic poles of the rotor and the rotary cylinder to form a magnetic fluid mass, and the target liquid is placed between the magnetic fluid mass. It is arranged so as to be sandwiched and moved in a spiral shape. In order to make the magnetic fluid pump a stable structure, the rotor and pressure generator are housed in a cylindrical outer shell and sealed (however, the inlet and outlet of the spiral pipe can be taken out to the outside) It is preferable to rotatably mount the rotary cylinder on the outer side of the shell. At this time, in order to reduce the rotation resistance and rotate stably, it is preferable to interpose a bearing between the cylindrical outer shell and the rotary cylinder. The rotor and the rotary cylinder can be rotated by using, for example, various small motors arranged close to each other, and by rotating one of the rotor and the rotary cylinder, both of them are simultaneously attracted by the attraction action of both permanent magnets. It can be rotated. The rotating mechanism of the rotor and the rotating cylinder and the motor are selected according to the application.

An embodiment of the present invention will be described below based on the conceptual diagrams shown in FIGS. FIG. 1 shows the pressure generator 5
FIG. 2 shows a rotor 1 arranged on the central side of FIG. 2 (see FIG. 2). The rotor 1 has a rotary shaft 2 and is provided with a plurality of permanent magnets 3a and 3b facing each other. It is a thing. The rotating shaft 2 is rotatably mounted on the upper lid 8b and the lower lid of the cylindrical outer shell 8 of FIG. 3, and the bearing 2a is attached to this mounting position, and the upper lid 8b for connecting the upper end portion to the motor. It is longer so that it is located higher.
FIG. 2 shows a cylindrical pressure generating portion 5 formed by spirally winding a plurality of pipes 4 so as to surround the rotor 1 arranged on the center side. The spiral pipe 4 is for moving the magnetic fluid (lump) and the target liquid in a spiral shape, and has a suction port 6 and a discharge port 7.

FIG. 3 shows a cylindrical shell 8 for covering the pressure generating portion 5 of FIG. The cylindrical outer shell 8 has an upper lid 8b and a lower lid, and the upper lid and the lower lid each have an outlet for taking out the suction port 6 and the discharge port 7 of the spiral pipe 4 of the pressure generating unit 5 to the outside. There is 8a. Bearings 8c and 8d for installing the rotary cylinder 10 of FIG. 5 are attached to the circumferential portions of the upper lid 8b and the lower lid. 4 shows a state in which the inlet 6 and the outlet 7 of the pressure generator 5 of FIG. 2 are taken out to the outside and the cylindrical outer shell 8 of FIG. 3 is housed and hermetically sealed. In addition, the shaft mounting portion 9 provided on the upper lid 8b of the cylindrical outer shell 8
The rotary shaft 2 of the rotor 1 is rotatably attached to the rotor via a bearing 2a.
It can be connected to the motor by making it longer than b.

FIG. 5 shows a rotary cylinder 10 which is rotatably mounted on the outer side of a cylindrical outer shell 8 and is attracted to the outer side relative to the plurality of permanent magnets 3a, 3b of the rotor 1. A plurality of permanent magnets 11a and 11b are provided at positions such that they meet each other. The permanent magnets 11a, 11 of the rotary cylinder 10
More specifically, b is provided so as to be positioned relative to the permanent magnets 3a and 3b of the rotor 1 in terms of radiation. Figure 6
Is an external view showing the configuration of the main part of the magnetic fluid pump. Here, the cylindrical outer shell 8 in which the pressure generating part 5 and the rotor 1 of FIG. On the outer side of the plurality of permanent magnets 11a and 11a, as shown in FIG.
The rotary cylinder 10 provided with b is rotatably mounted via bearings 8c and 8d.

By simultaneously rotating the rotary cylinder 10 and the rotor 1 with a motor (not shown), the magnetic fluid sucked into the spiral pipe 4 forming the pressure generating portion 5 is spirally wound in one direction. It can be operated as a magnetic fluid pump. When operating as a magnetic fluid pump, the rotor 1 and the rotary cylinder 10 are simultaneously rotated by a motor, and the permanent magnets 3a, 3 and 3 of the rotor 1 are rotated.
b and the permanent magnets 11a and 11b of the rotary cylinder 10 are attracted to each other, the magnetic fluid from the suction port 6 of the spiral pipe 4 is transferred to the permanent magnets 3a and 3b of the rotor 1 and the rotary cylinder 10. The permanent magnets 11a and 11b are used to attract by a magnetic force to form a magnetic fluid mass between the permanent magnets, and a target liquid (blood, drug, water, etc.) is sandwiched between the front and rear magnetic fluid masses. It is moved in a spiral shape and discharged. That is, since the rotor 1 and the rotary cylinder 10 rotate by attracting the permanent magnets 3a, 3b and 11a, 11b, the permanent magnets move away from the suction port 6 of the spiral pipe 4 over time, Magnetic fluid is left behind. During this period, the target liquid fills the spiral pipe 4.

Next, the permanent magnets 3a, 3b and 11a, 11b having opposite magnetic poles approach the suction port 6 of the spiral pipe 4, so that the subsequent magnetic fluid is attracted by the magnetic effect of the permanent magnet. Therefore, the target fluid that has formed a magnetic fluid mass in the spiral pipe 4 and has filled the spiral pipe 4 is spirally sandwiched between the preceding magnetic fluid mass and the subsequent magnetic fluid mass. And is discharged from the discharge port 7. By repeating such operations, the target liquid is sequentially moved to the ejection port 7, whereby a desired amount of the target liquid can be ejected. The discharge pressure of such an operation is carried by the magnetic fluid held in the magnetic field by the permanent magnets 3a and 3b of the rotor 1 and the permanent magnets 11a and 11b of the rotary cylinder 10, and the strength of each of these permanent magnets. , The area of the magnetic field formed by the permanent magnets of the rotor 1 and the rotary cylinder 10 is determined. Further, the discharge amount is determined by the inner diameter of the spiral pipe 4 and the rotation speed of the rotor 1 (rotating cylinder 10). Therefore, the capacity of the pump depends on the inner diameter of the spiral pipe 4, the number of spiral turns, the diameter of the rotor 1 and the rotary cylinder 10, the body length, the magnetic force and size of each permanent magnet to be mounted, and the discharge amount and the discharge amount. The pressure can be controlled by the rotation speed of the motor that rotates the rotor 1 and the rotary cylinder 10. In the magnetic fluid pump of the present invention, in order to finally separate the target liquid and the magnetic fluid (lump) on the discharge port 7 side, a magnetic separation device is arranged on the discharge port 7 side, and the magnetic fluid separated here is separated. By connecting a pipe line that circulates the fluid to the suction port 6 side, it is possible to easily form a magnetic fluid mass before and after sandwiching the target liquid, and it is possible to reduce the cost of the magnetic fluid. The structure for this purpose is omitted here.

[0014]

EXAMPLE An example of the magnetic fluid pump of the present invention will be described below with reference to FIGS. The magnetic fluid pump of this embodiment is basically a prototype manufactured by using the structure shown in FIGS. 1 to 6 as a basic structure. Here, the rotor 1 is rotated by the small motor 17, and the rotary cylinder 10 is rotated. Is rotated at the same time as the rotor 1, and the magnetic separation device 14 is arranged on the discharge port 7 side so that the magnetic fluid is separated from the target liquid, water, and circulated to the suction port 6 side. is there. In this embodiment, a vinyl chloride pipe having an outer diameter of 8 mm and an inner diameter of 6 mm is closely wound in a spiral shape by winding the spiral pipe 4 and winding the spiral pipe 4 to obtain an inner diameter of 52 mmφ and an outer diameter of 68 m.
A cylindrical pressure generating portion 5 having a diameter of mφ is formed, and a cylindrical outer shell 8 made of a resin is covered on the pressure generating portion to form a fixed portion. Further, a rotating cylinder is provided outside the cylindrical outer shell via bearings 8c and 8d. 10 was rotatably mounted. At this time, the suction port 6 and the discharge port 7 of the pressure generating unit 5 are taken out to the outside, and as shown in FIG. 7, the suction pipe 12 is provided on the suction port 6 side and the discharge port 7 is provided on the discharge port 7 side. Is connected to the discharge pipe 13 via a magnetic separator 14. Further, the magnetic separation device 14 and the suction port 6 side are connected by a circulation pipe 15 so that the magnetic fluid separated from water by the magnetic separation device 14 is circulated in the spiral pipe 4. The discharge pipe 13 has a pressure gauge 16 for measuring the discharge pressure of water and magnetic fluid and a flow meter 1 for measuring the discharge flow rate.
8 was placed.

A rotor 1 equipped with two-pole permanent magnets 3a and 3b is arranged on the center side of the pressure generating portion 5, and a rotary shaft 2 is provided.
Both ends of the cylindrical outer shell 8 are rotatably supported by the upper and lower lids 8b of the cylindrical outer shell 8 via bearings (2a), and the rotary shaft 2 is connected to the rotary shaft of a small motor 17 provided on the upper lid 8b of the cylindrical outer shell 8. Then, the small motor is driven to rotate the rotor 1. The rotary cylinder 10 rotatably mounted on the outside of the cylindrical outer shell 8 via bearings 8c and 8d has a permanent magnet of the rotor 1 at a position relative to the two-pole permanent magnets 3a and 3b of the rotor 1 at the center. Two permanent magnets 11 of opposite poles facing each other
a and 11b are arranged, and here, the rotary cylinder 10
The rotor 1 is simultaneously rotated by the rotation of the rotor 1 due to the attraction action with the permanent magnets 3a and 3b of the rotor 1. In this embodiment, the rotor 1 is rotated by the small motor 17 to rotate the rotary cylinder 10 at the same time.
You may make it rotate 0 and rotate the rotor 1 simultaneously.

Table 1 shows the material and size of each part constituting the magnetic fluid pump of this embodiment, and Table 2 shows the properties of the magnetic fluid used.

[0017]

[Table 1]

[0018]

[Table 2]

In the magnetic fluid pump of the embodiment having the above-mentioned structure, the magnelude liquid made by NSK (Nippon Seiko Co., Ltd.) is taken as a magnetic fluid into the spiral pipe 4 as a magnetic fluid mass by a magnetic attraction force. The magnetic fluid is moved, and water is sandwiched between the magnetic fluid masses and moved to be discharged from the discharge port 7. The water can be discharged separately from the magnetic fluid (mass) on the discharge port 7 side. This magnetic fluid pump was operated by a small motor 17 driven under a certain condition to discharge water and magnetic fluid from the discharge port 7, and the pressure gauge 16 measured the change over time in its pressure characteristics.
The measurement result is shown in FIG.

The pressure characteristics of the water and the magnetic fluid are obtained on the basis of measurement information from the pressure gauge 16 and the flowmeter 18 provided near the discharge port 7. As shown in FIG. 8, changes over time in the pressure characteristics of water and magnetic fluid show regular and small changes, indicating that stable pump characteristics can be obtained over a long period of time. Further, no magnetic fluid was found in the target liquid water after passing through the magnetic separator 14. In this embodiment, the pressure generating portion 5 is formed of eight turns of the spiral pipe 4, and the rotor 1 on the central side of the pressure generating portion 5 and the outer rotary cylinder 10 are made permanent magnets 3a, 3b and 11a. 11b are simultaneously rotated by the attraction action of 11b, and the permanent magnets of the rotor 1 and the rotary cylinder 10 attracting the magnetic fluid in the spiral pipe 4 cause the pump to rotate in a spiral manner. It was possible to make it more compact and lighter.

[0021]

Since the magnetic fluid pump of the present invention does not use a solid valve, there is no problem of heat generation or mixing of foreign matters, and the pressure generating portion is formed by a spiral pipe, and the pressure generating portion is formed on the center side. A rotor provided with a plurality of permanent magnets, and a rotary cylinder provided with a plurality of permanent magnets of different polarities facing the permanent magnets of the rotor on the outer side are arranged. Since the magnetic fluid (lump) in the spiral pipe is spirally rotated by the action of the rotor and the permanent magnet of the rotary cylinder which are attracted to each other and rotated at the same time,
The pump can be made more compact and lightweight, and stable pump characteristics can be ensured for a long time, so that the above problems when applied to a small pump such as a pump for an artificial heart can be solved.

[Brief description of drawings]

FIG. 1 is a three-dimensional explanatory diagram showing a structural example of a rotor according to an embodiment of the present invention.

FIG. 2 is a three-dimensional explanatory view showing a pressure generating portion formed by spirally winding a plurality of pipes so as to surround the rotor of FIG.

FIG. 3 is a three-dimensional explanatory view showing a cylindrical outer shell that covers the outside of the pressure generating portion of FIG.

FIG. 4 is a three-dimensional explanatory view showing a state in which a cylindrical outer shell is placed outside the pressure generating portion of FIG. 2 and both ends (suction port and discharge port) of the suction port and the discharge port spiral pipe are taken out and covered.

FIG. 5 is a three-dimensional explanatory view showing a rotary cylinder that is rotatably mounted on the outside of a cylindrical outer shell that covers the outside of the pressure generating unit as shown in FIG.

FIG. 6 is a stereoscopic explanatory view showing a structural example of a main part of the magnetic fluid pump according to the embodiment of the present invention.

FIG. 7 is a partially cutaway three-dimensional explanatory view showing a structural example of a magnetic fluid pump used in an example (experimental example) of the present invention.

8 is an explanatory diagram showing changes over time in pressure characteristics of the magnetic fluid pump obtained in the example (experimental example) of FIG. 7.

[Explanation of symbols]

1: Rotor 2: Rotation axis 2a: Bearing 3a, 3b: Permanent magnet 4: spiral pipe 5: pressure generating part 6: Suction port 7: Discharge port 8: Cylindrical outer shell 8a: Extraction hole 8b: Upper (lower) lid 9: (Rotor) mounting part 10: rotating cylinder 11a, 11b: permanent magnet 12: Intake pipe 13: Discharge pipe 14: Magnetic separation device 15: Circulation piping 16: Pressure gauge 17: Small motor 18: Flow meter

Claims (2)

[Claims] 1. A plurality of opposing magnetic poles of different phases face each other on the center side and the outer side of a cylindrical pressure generating portion formed by two or more spiral pipes having suction ports and discharge ports at both ends. It is equipped with a rotor with a permanent magnet in it, a rotary cylinder, and a drive device for the rotor and rotary cylinder. By rotating this rotor and rotary cylinder at the same time, the magnetic fluid taken in the spiral pipe is rotated. It is configured such that it is attracted between the child and the magnetic poles of the rotary cylinder and moved in a spiral shape, and the target liquid is sandwiched between the magnetic fluid masses formed before and after it and moved in a spiral shape to be discharged. Magnetic fluid pump. 2. A circulation path of a magnetic fluid is connected to the outlet side, the magnetic fluid circulating to the inlet side via a magnetic separation device for separating the magnetic fluid, and the magnetic fluid is separated from the target liquid on the outlet side. The magnetic fluid pump according to claim 1, wherein the magnetic fluid pump is configured to circulate to the suction port side.