JP2008025430A - Tube pump - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a compact tube pump by integrally constituting a motor portion and a pump portion. <P>SOLUTION: In the tube pump that has a structure in which a portion of a flexible tube 1 is compressed and a compression point 11 thereof is shifted to discharge liquid inside the flexible tube 1, the pump portion and the motor portion are arranged in the same plane, and an eccentric rotating body 4 for compressing the portion of the flexible tube 1 and a rotor 5 of a driving motor are integrally constituted, thereby obtaining a compact and high-performance pump. The tube pump includes a rotating ring 3 on an inner circumference surface of the tube that is winded approximately once in a circular shape, the eccentric rotating body 4 that rotates while contacting the rotating ring being integrated with the rotor 5 of the driving motor. The tube pump can reduce a space for the motor or a speed-reduction mechanism, and realize downsizing thereof as compared to a conventional pump with similar system. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

The present invention relates to a tube pump having a structure in which a part of a flexible tube is compressed and its compression point is moved to send out liquid inside the tube.

As a pump for supplying fuel to a fuel cell used in a small portable device, a tube compression type tube pump can be considered. Conventionally, such a tube pump has its drive motor and speed reducer outside the pump case and connected by a shaft.
JP 2006-46195 A JP 2004-68618 A

Since the speed reducer and motor are mounted coaxially with the compression pump as in this example, the overall dimensions are large and the storage volume of the pump is large, especially for fuel pumps for fuel cells used in small portable devices, etc. In that case, it has hindered the miniaturization of equipment.

  An attempt is made to reduce the volume by integrally joining the eccentric rotating body and the rotor, eliminating the speed reducer, and integrally configuring the motor and the pump.

In a pump with a structure that forms a flexible tube in a circular shape, compresses a part of the tube by rotating an eccentric rotating body, and sucks and discharges the liquid inside the tube, the pump unit and the motor unit are arranged on the same plane. Further, an eccentric rotating body and a rotor of a drive motor are integrally configured to obtain a small and high-performance pump, and FIG. 1 shows an example of the embodiment. In FIG. 1a, a rotating ring 3 is installed on the inner circumference of the tube 1 wound approximately once in a circle, and an eccentric rotating body 4 that rotates in contact with the rotating ring is installed. The eccentric rotating body is connected to the rotor 5 of the drive motor. Compared to conventional pumps of the same type, the tube pump with an integrated structure can save space for the motor and speed reduction mechanism and can be downsized.

The present invention reduces the volume of the pump by integrating the eccentric rotating body of the pump unit and the rotor of the drive motor, and installing the motor unit and the pump unit on the same plane, and the motor uses a permanent magnet synchronous motor. The yoke portion of the magnet rotor and the eccentric rotating body of the pump are integrally coupled, and the form is a method of housing the motor on the inner peripheral side of the flexible tube wound approximately once in a circular shape, and the flexible tube There are two embodiments of the method of housing the motor on the outer periphery.

According to the present invention, in a fuel cell fuel pump or the like used in a portable device, use of space as effectively as possible leads to miniaturization. By disposing the pump unit and the motor unit on the same plane and integrating the eccentric rotating body and the rotor of the pump unit, it is possible to reduce the size by eliminating useless space. Moreover, the method of rotating the tube once in a spiral is useful for minimizing the space of the case when the tube is pulled out.
In addition, the use of a brushless motor ensures long life and high reliability. The motor-driven inverter circuit has a good interface with the flow rate control of the pump and can cope with various control patterns.

An embodiment of the present invention will be described with reference to FIGS.
FIG. 1 is a first embodiment of the present invention, FIG. 1a is a plan view, and FIG. 1b is a sectional view. 2A is a plan view, FIG. 2B is a cross-sectional view, FIG. 2C is a view showing how to wind the tube, FIG. 3 is a third embodiment, and FIG. 3A is a plan view. FIG. 3b shows a cross-sectional view. FIG. 4 is a view for explaining how to wind and pull out the storage case ring and the tube of the third embodiment. 4a is a diagram showing two holes opened in the storage case, FIG. 4b is a diagram showing a spirally wound tube, and FIGS. 4c and 4d are cross-sectional views of the holes opened in the storage case, respectively. FIG. 4e is a view showing how to pull out the tube spirally wound around the storage case. FIG. 5 is a structural diagram of a conventional tube pump, and shows an example of FIG. 1 of JP-A-2006-46195.

FIG. 1 is a first embodiment of the present invention and shows an embodiment of [Claim 3]. FIG. 1a is a plan view and FIG. 1b is a sectional view. The flexible tube 1 is wound almost once inside the storage case 19, and a rotating ring 3 is rotatably installed on the inner peripheral surface of the tube, and there is an eccentric rotating body 4 that rotates in contact with the rotating ring. The eccentric rotating body has a structure integrated with the rotor 5 of the drive motor, and the rotor includes a magnet 6 and a yoke 7 and a support plate 9 that connects the rotor and the shaft 8. A structure in which the thickness of the yoke 7 is partially changed to rotate while the outer periphery of the rotor is eccentric, and when the eccentric rotating body 4 rotates, a portion 10 having a large eccentricity pushes up a part of the rotating ring 3 that is circumscribed, and is flexible The tube 1 is compressed. Since this compression point 11 moves with rotation, the fluid sucked from one end 12 of the tube is discharged from the other end 13 (the rotation direction of the rotor in the figure is CW). The motor is an outer rotor type motor and is housed in the inner periphery of the rotating ring 3. The stator 16 is on the inner peripheral side of the rotor 5 and accommodates a stator winding 17 (partially omitted in the drawing), a bearing 18 and a shaft 8. In this embodiment, the flexible tube 1 is wound almost once in the same plane inside the storage case 2.

FIG. 2 shows a second embodiment, which is an embodiment of [Claim 4]. 2a is a plan view and FIG. 2b is a cross-sectional view. In the first embodiment of FIG. 1, the tube 1 is wound almost once in the same plane inside the storage case 19, and the angle wound to avoid overlapping of both ends is not 360 degrees, but 300 degrees. It is wound in the range of ~ 340 degrees. The suction side tube 12 and the discharge side tube 13 are drawn from the upper part of the storage case 2. On the other hand, in the second embodiment, the tube can be wound approximately 360 degrees by spirally winding it around the storage case in which the tube is stored and pulling out both ends thereof to the left and right. As in the first embodiment, the storage case can be made smaller than when both ends 12 and 13 of the tube are pulled out upward. FIG. 2c is a view showing a state in which the storage case is wound almost once in a spiral. Other structures are the same as those in FIG.

FIG. 3 shows a third embodiment, which is an embodiment of [Claim 6]. 3a is a plan view and FIG. 3b is a cross-sectional view. The motor is an inner rotor type, and the storage case ring of [Claim 5] is used to store the tube. The tube 1 is pulled out from the inner peripheral side of the storage case ring 2 to the outer peripheral side through the first hole 14, and the outer periphery. The side is spirally wound about one turn and guided from the second hole 15 to the inner peripheral side. By doing so, both ends 12 and 13 of the tube can be pulled out. A rotating ring 3 circumscribing the tube 1 is rotatably installed, and an eccentric rotating body 4 circumscribing the rotating ring is installed. The eccentric rotating body 4 is integrally joined with the rotor 5 of the motor. A stator 16 is installed on the outer periphery of the rotor to constitute a motor.

4 is a diagram for explaining the details of the storage case ring of the third embodiment, FIG. 4a is a sectional view of a hole through which the tube of the storage case ring is passed, FIG. 4b is a diagram showing a state where the tube is wound, FIG. 4c is an explanatory view of the first hole opened in the storage case ring. FIG. 4d is also an explanatory view of the second hole. FIG. 4e shows that the tube is drawn from the inner peripheral side of the storage case ring to the outer peripheral side through the first hole, wound almost once in a spiral, and guided from the second hole to the inner peripheral side of the storage case ring. It is a figure explaining the state to be taken.

Since the third embodiment is an inner rotor type motor, the stator core is on the outer periphery of the pump. The thickness of the electromagnetic steel sheet can be increased, and the magnetic circuit of the teeth portion and the yoke portion can be increased. Moreover, since the space of a coil | winding can also be taken large, the number of turns can be taken large. This is the most volume efficient pump system that can reduce the power consumption of the motor.

In general, there is a relationship represented by the following equation (1) between the discharge amount in the case of such a tube pump and the rotational speed of the eccentric rotator, that is, the motor.
M = κ1 × d × d × D × N (1)
Where M = discharge rate [mml / min.]
d = inner diameter of the tube [mm]
D = Ring diameter around which the tube is wound [mm]
N = Motor speed [rpm]
κ1 = constant or torque T applied to the motor shaft is expressed as follows.
T = κ2 × ρ × D × d (2)
ρ = tube compression torque coefficient κ2 = constant From these relational expressions, the first and second embodiments are used when the torque is large and the rotational speed is low. The third embodiment is used when the torque is small and the rotational speed is high.

In the first embodiment, the tube can be pulled out on the same plane as the pump case. Secondly, in the embodiment, the pump case can be pulled out from the left and right on the same plane. In the third embodiment, the pump case can be pulled out vertically from the center. As described above, the system of an appropriate embodiment can be used depending on the conditions accommodated in the device.

  The motor used here is a motor called a permanent magnet synchronous motor, and this motor is the most excellent in volume efficiency and motor efficiency because it is brushless. Since there is no brush, it is highly reliable and has a long life.

As the rotor, an Nd—Fe—B sintered magnet or an Nd—Fe—B resin bonded magnet is used. The stator is laminated with electromagnetic steel plates and wound. The connection is a three-phase star connection.

  The drive circuit uses a three-phase inverter drive circuit. Normally, Hall elements, Hall ICs, or encoders are used to detect the magnetic pole position of the rotor magnet. However, if a pump that is as small as possible is required as in this patent, such position detection is not used and sensorless. Use the drive method.

Since the rotational speed of the motor is used in a relatively low rotational speed range, there is little iron loss, and copper loss accounts for most of the loss. For this reason, the number of turns of the stator winding is increased to reduce the current. In this case, increasing the number of turns of the winding increases the coil end, thereby increasing the thickness of the case. In order to avoid this as much as possible, the winding is not concentrated winding but concentrated winding. In addition, measures can be taken to increase the number of slots and reduce the number of turns per pole to keep the coil end small.

Further, since it is used at a low rotational speed, generally used means for reducing the cogging torque and torque ripple are taken in order to suppress fluctuation of the outflow amount due to the influence of cogging torque and torque ripple.

The top view of the tube pump of the outer rotor system of the 1st example of the present invention Sectional view of AOB Plan view of the outer rotor type tube pump of the second embodiment Sectional view of AOB Illustration of a spirally wound tube Plan view of the inner rotor type tube pump of the third embodiment Sectional view of AOB Sectional view of the storage case ring in the third embodiment Figure with tube spirally wound around its storage case ring Explanatory drawing of the first hole of the storage case ring (A-A 'cross section) Explanatory drawing of the 2nd hole of a storage case ring (B-B 'cross section) Illustration of passing the tube through the storage case ring Illustration of conventional structure

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Flexible tube 2 Storage case ring 3 Rotating ring 4 Eccentric rotating body 5 Rotor 6 Magnet 7 Rotor yoke 8 Shaft 9 Support plate 10 Large part of the eccentric part 11 Tube compression point 12 One end of the tube 13 The other end 14 The tube 14 One hole 15 Storage case ring Second hole 16 Stator core 17 Coil 18 Bearing 19 Storage case

Claims (6)

In a tube pump having a structure in which a part of a flexible tube is compressed and its compression point is moved to send out the liquid inside the tube, a rotating ring that rotates in contact with the flexible tube wound approximately once in a circle and the rotating ring An eccentric rotating body that rotates in contact with a tube, and a tube pump in which a rotor and a stator of a motor that provides rotation to the eccentric rotating body are housed on substantially the same plane The tube pump according to claim 1, wherein the rotor of the motor is configured integrally with the eccentric rotating body. An eccentric rotor is integrally joined to the outer periphery of the rotor of an outer rotor type permanent magnet synchronous motor, a rotating ring that freely rotates in contact with the outer periphery of the eccentric rotor is provided, and a flexible tube is in contact with the outer periphery of the rotating ring. The tube pump according to claim 2, wherein the tube pump is installed.   The tube pump according to claim 3, wherein the tube pump has a structure in which both ends of the tube are pulled out to the outside by spirally rotating in a case accommodating the flexible tube.   The inner and outer rings are circular rings, and two holes are provided from the outer circumference side to the inner circumference side, and the flexible tube is passed from the inner circumference side of the ring to the outer circumference side through the first hole. The tube pump according to claim 2, wherein a flexible tube storage case ring having a structure in which the outer periphery is spirally wound almost once and guided from the outer periphery side to the inner periphery side through the second hole. An eccentric rotor is integrally joined to the inner circumference of the rotor of the inner rotor type permanent magnet synchronous motor, and a rotary ring that rotates freely in contact with the inner circumference of the eccentric rotor is provided. A tube pump having a structure in which a flexible tube is in contact with the tube and the tube is housed in the housing case according to claim 5.

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