JP2007170199A - Pump - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a pump rotatable at a high speed while minimizing wear between a bearing and a shaft. <P>SOLUTION: This pump comprises an impeller 1 having a large number of vanes 2 on the outer periphery of a cylindrical part 1A and having a rotor magnet 3 on the inner periphery of the cylindrical part 1A, a motor stator 4 installed on the inner peripheral side of the rotor magnet 3 and rotatingly driving the impeller 1, a separator 6 partitioning airtight the impeller 1 from the motor stator 4, and a pump casing 5 having a suction port 9 and a discharge port 10 for sucking and discharging a liquid. Dynamic pressure generating grooves 12 generating dynamic pressure by the rotation of the impeller 1 are formed in the outer peripheral surface 8a of the bearing of the impeller 1 and at least one of the cylindrical surface 6a of the separator 6 and the cylindrical surface 5a of the pump casing 5 facing the outer peripheral surface of the bearing. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a small pump that is driven by a motor and sucks and discharges a liquid such as a refrigerant, methanol, or water.

  In recent years, for example, a refrigerant-type cooling system that circulates and cools a refrigerant of an electronic component such as a CPU or a fuel cell for a small device has been attracting attention. The refrigerant circulation pumps used in such refrigerant-type cooling systems and the methanol transport pumps used in fuel cells have many restrictions on the space to be mounted. The demand for is increasing.

  FIG. 4 is a cross-sectional view showing an example of this type of conventional pump (see, for example, Patent Document 1), and FIG. 5 is a bottom view of the pump casing.

  In the pump shown in FIGS. 4 and 5, reference numeral 101 denotes an impeller, in which a large number of blades 102 are formed on the upper outer periphery, and a rotor magnet 103 is provided on the inner periphery. Reference numeral 104 denotes a motor stator provided on the inner peripheral side of the rotor magnet 103. Reference numeral 105 denotes a pump chamber for accommodating the impeller 101 and at the same time recovering the kinetic energy imparted to the fluid by the impeller 101 and leading it to the discharge port. A pump casing 106 includes a separation plate that forms part of the pump casing 105 and hermetically partitions the motor stator 104 and the impeller 101. The rotor magnet 103 and the motor stator 104 are sandwiched by a partition wall 106 </ b> A of the separation plate 106. Are facing each other. Reference numeral 111 denotes a packing that seals the joint between the main body portion of the pump casing 105 and the separation plate 106. The pump casing 105 is provided with a fluid suction port 109 and a discharge port 110.

  A shaft 107 serving as the rotation center of the impeller 101 is disposed at the center of the pump. The shaft 107 is fixed to the separation plate 106, and the impeller 101 is rotatably supported around the shaft 107 via a cylindrical bearing 108. The bearing 108 is fixed to the center portion of the impeller 101.

  In the pump having this configuration, when electric power is supplied from an external power source, a current controlled by an electric circuit provided in the pump flows in the coil of the motor stator 104, and a rotating magnetic field is generated. When this rotating magnetic field acts on the rotor magnet 103, a physical force is generated in the rotor magnet 103, and the impeller 101 integrated with the rotor magnet 103 rotates.

  The blade 102 provided on the upper outer periphery of the impeller 101 gives kinetic energy to the fluid that flows in from the suction port 109 by the rotation of the impeller 101, and the pressure of the fluid in the pump casing 105 gradually increases due to the kinetic energy. It is raised and discharged from the discharge port 110.

As described above, in the conventional small pump, the blade 102 and the rotor magnet 103 are integrally formed, and the motor stator 104 is inserted therein, thereby minimizing the length of the entire pump in the rotation axis direction as much as possible.・ Thinners are being made thinner.
JP 2004-190562 A

  By the way, with the miniaturization of devices, the amount of heat generated by electronic components such as CPUs has also increased, and accordingly, higher performance and longer life of pumps for improving cooling performance have been demanded. Yes.

  However, if the impeller 101 is rotated at a high speed in order to meet these requirements, the wear when the bearing 108 integrated with the impeller 101 slides on the outer periphery of the shaft 107 is accelerated. As a result, the pump There was a problem that the lifespan of the device would be shortened.

  In consideration of the above circumstances, the present invention provides a pump that can achieve high speed rotation while minimizing wear between the bearing and the shaft, thereby achieving high performance and long life. The purpose is to do.

  In order to achieve the above object, the present invention provides an impeller having a large number of blades on the outer periphery of a cylindrical portion and having a rotor magnet on the inner periphery of the cylindrical portion, and provided on the inner peripheral side of the rotor magnet. A motor stator that rotates the motor, a separation plate that hermetically partitions the impeller and the motor stator, and a pump casing having a suction port and a water discharge port for sucking and discharging liquid, and a central cylindrical portion of the impeller A resistor that generates a dynamic pressure by the rotation of the impeller is provided on at least one of the outer peripheral surface and the cylindrical surface of the separation plate facing the outer peripheral surface.

  With this configuration, the dynamic pressure is generated between the outer peripheral surface of the central cylindrical portion of the impeller and the cylindrical surface of the separating plate facing the impeller, so that the impeller can be rotated at high speed without contact with the shaft. The action can be achieved.

  The present invention has an effect of providing a high-performance and long-life pump capable of rotating an impeller at a high speed without wearing a bearing.

  An embodiment of the present invention includes an impeller having a large number of blades on the outer periphery of a cylindrical portion and a rotor magnet on the inner periphery of the cylindrical portion, and provided on the inner peripheral side of the rotor magnet, and rotationally driving the impeller An outer peripheral surface of the central cylindrical portion of the impeller, and a pump casing having a suction port and a water discharge port for sucking and discharging liquid, and a motor stator for airtightly separating the impeller and the motor stator. In addition, a resistor (dynamic pressure generating portion) that generates dynamic pressure by the rotation of the impeller is provided on at least one of the cylindrical surface of the separation plate facing this. Here, the central cylindrical portion of the impeller corresponds to a bearing that rotatably supports a shaft fixed to the pump casing or the separation plate.

  With this configuration, a dynamic pressure can be generated between the separation plate and the impeller according to the rotation of the impeller, and thereby the impeller can be rotated at high speed without contact with the shaft. Therefore, the impeller can be rotated at a high speed without wearing the bearing, and a high-performance and long-life pump can be provided. The shaft serves to suppress eccentricity when the impeller starts rotating.

  Here, the resistor is preferably composed of a plurality of grooves.

  In this case, since the processing at the time of forming the resistor can be easily performed, the cost of the pump can be reduced.

  Further, the grooves are preferably formed in the same predetermined shape and arranged at the same predetermined interval.

  In this case, since the dynamic pressure can be uniformly generated when the impeller rotates, it is possible to stabilize the rotation of the impeller and prevent vibration and noise of the pump.

  Moreover, in this invention, you may make it provide the said resistor in at least one of the outer peripheral surface of the center cylindrical part of an impeller, and the cylindrical surface of the pump casing which faces this. Alternatively, the resistor is provided on at least one of the outer peripheral surface of the central cylindrical portion of the impeller, the cylindrical surface of the separation plate facing the central cylindrical portion, and the cylindrical surface of the pump casing.

  Embodiments of the present invention will be described below with reference to the drawings.

  1 is a structure of a pump in the present embodiment, FIG. 2 is a bottom view of the pump, and FIG. 3 is a perspective view of an impeller in the pump.

  In these drawings, reference numeral 1 denotes an impeller having a cylindrical portion 1A and an upper surface wall 1B. The impeller 1 has a large number of blades 2 on the outer periphery of the cylindrical portion 1A, and an inner peripheral portion of the cylindrical portion 1A. The rotor magnet 3 is provided. Moreover, it has the bearing 8 which is the center cylindrical part comprised, for example with carbon in the center part of the upper surface wall 1B. The bearing 8 has a cylindrical shape, and the inner diameter thereof is set to a dimension that ensures a slight clearance (for example, about 0.05 mm to 1.0 mm) with an outer periphery of a shaft 7 described later.

  Here, in the impeller 1, the blade 2 and the rotor magnet 3 may be formed of different materials, and may be integrated by fitting them, or the blade 2 and the rotor magnet 3 may be formed of the same magnetic resin material. You may comprise integrally.

  Further, the bearing 8 may be formed of a material having good lubricity different from that of the blade 2 and the rotor magnet 3 and then fitted and integrated with them, or may be formed of the same material as the blade 2 and the rotor magnet 3 and integrated. May be used.

  In FIG. 1, 4 is a motor stator provided on the inner peripheral side of the rotor magnet 3, 5 accommodates the impeller 1, and at the same time recovers the kinetic energy imparted to the fluid by the impeller 1 to the discharge port 10. A pump casing 6 having a pump chamber for guiding the air gap between the motor stator 4 and the impeller 1 is a separation plate that hermetically partitions the rotor stator 3 and the motor stator 4. Are facing each other.

  Reference numeral 11 denotes a packing which seals the joint between the main body portion of the pump casing 5 and the separation plate 6 and forms a seal structure with the external atmosphere. As this packing, an O-ring may be employed, but a seal structure by welding the main body portion of the pump casing 5 and the separation plate 6 may be employed. The pump casing 5 is provided with a suction port 9 and a discharge port 10 for sucking and discharging (inflow / outflow) of fluid from the rotational radius direction of the impeller 1.

  The separating plate 6 is formed with an annular groove 6B, and the lower part of the cylindrical portion 1A of the impeller 1 having the rotor magnet 3 is accommodated in the annular groove 6B. A cylindrical recess 6 </ b> C that accommodates and arranges the lower end of the bearing 8 is formed at the center of the separation plate 6.

  A resistor (dynamic pressure generating portion) that generates dynamic pressure by rotation of the impeller 1 is provided on the outer peripheral surface 8a of the bearing lower end portion of the impeller 1 that faces the inner cylindrical surface 6a inside the cylindrical recess 6C. As a result, a dynamic pressure generating groove 12 is formed. A cylindrical recess 5A for accommodating and arranging the upper end of the bearing 8 is formed at the center of the pump casing 5, and the outer peripheral surface of the bearing upper end of the impeller 1 faces the cylindrical surface 5a inside the cylindrical recess 5A. A similar dynamic pressure generating groove 12 is also formed in 8a.

  As the shape of the dynamic pressure generating groove 12, a substantially V-shaped herringbone arrangement or a spiral groove pattern shown in FIG. 3 is used, but a wave shape, a lattice shape, a circle, a triangle, a square, an ellipse, a multi Even if it is an embossed shape such as a square, a dynamic pressure is generated and the same effect can be obtained. The pitch, width and depth of the dynamic pressure generating grooves 12 are preferably 0.02 to 10 mm. In the present embodiment, a plurality of power generation grooves 12 are formed in the circumferential direction along the outer peripheral surface 8a of the bearing 8 with the same shape and the same pitch as grooves having a substantially V shape in plan view. .

  In addition to the dynamic pressure generating groove 12 having a groove shape, the resistor may be a protrusion constituting a wing. For example, a plurality of protrusions constituting the blades are provided on the outer peripheral surface 8a of the bearing 8 along the circumferential direction. In this case, the protrusion may be formed of a material different from that of the bearing 8 and may be fitted to the outer peripheral surface 8a to be integrated with the bearing 8 or may be bonded. Further, in order not to lower the magnetic force, the protrusions may be integrated with the same material as the rotor magnet 3 or may be bonded together. Furthermore, this protrusion may be integrated with the bearing 8 with the same magnetic material as the blade 2 and the rotor magnet 3.

  In FIG. 1 and FIG. 3, the dynamic pressure generating groove 12 (may be a protrusion) is formed on the outer peripheral surface 8a of the bearing 8, but nothing is formed on the outer peripheral surface 8a and the outer peripheral surface 8a faces. Dynamic pressure generating grooves 12 (or protrusions) may be formed in the cylindrical surface 5 a of the pump casing 5 and the cylindrical surface 6 a of the separation plate 6. Alternatively, the dynamic pressure generating grooves 12 (or protrusions) may be formed on both the outer peripheral surface 8a of the bearing 8 and the cylindrical surface 5a of the pump casing 5 and / or the cylindrical surface 6a of the separating plate 6 facing the outer peripheral surface 8a. Good.

  Reference numeral 7 denotes a shaft fixed to the pump casing 5, which is inserted into a center hole 8 </ b> A of a bearing 8 provided at the center of the impeller 1, so that the bearing 8 of the impeller 1 can slide on the outer periphery of the shaft 7. It has become a structure. The shaft 7 may be fixed to the pump casing 5 or the separation plate 6 by press-fitting or insert molding as a separate part, or may be formed by integral molding of the same material as the pump casing 5 or the separation plate 6. . The shaft 7 may be configured to be able to slide freely between the impeller 1, the pump casing 5, and the separation plate 6.

  The impeller 1, the pump casing 5, and the separation plate 6 are mainly composed of a resin having excellent chemical resistance, particularly methanol resistance, such as PPS (polyphenylene sulfide).

  Next, the operation of the above-described pump will be described. When electric power is supplied from an external power source, a current controlled by an electric circuit provided in the pump flows in the coil of the motor stator 4 to generate a rotating magnetic field. When this rotating magnetic field acts on the rotor magnet 3, a physical force is generated in the rotor magnet 3. Since the rotor magnet 3 is integrated with the impeller 1, rotational torque acts on the impeller 1, and the impeller 1 starts to rotate by this rotational torque. The blade 2 provided on the upper outer periphery of the impeller 1 gives kinetic energy to the fluid that flows in from the suction port 9 by the rotation of the impeller 1, and the pressure of the fluid in the pump casing 5 is gradually increased by the kinetic energy. And discharged from the discharge port 10.

  At that time, the dynamic pressure generating groove 12 provided on the outer peripheral surface 8a of the bearing 8 of the impeller 1 moves between the inner cylindrical surface 6a of the separating plate 6 and the cylindrical surface 5a of the pump casing 5 facing each other. Since pressure is generated, the bearing 8 and the shaft 7 provided with a certain clearance are in non-contact rotation. As a result, the impeller 1 can be rotated at a high speed without causing the bearing 8 to wear, and a high-performance, long-life, small-sized pump can be provided.

  The pump of the present invention can be expected to be applied to various types of pumps used in a refrigerant-type cooling system that circulates and cools a refrigerant of an electronic component such as a CPU or a fuel cell for a small device.

It is a sectional side view of the pump in a present Example. It is a bottom view of the pump. It is a perspective view of the impeller in the pump. It is a sectional side view of the conventional pump. It is a bottom view of the pump.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Impeller 2 ... Blade 3 ... Rotor magnet 4 ... Motor stator 5 ... Pump casing 5a ... Cylindrical surface of the pump casing 6 ... Separation plate 6a ... Cylindrical surface of the separation plate 7 ... Shaft 8 ... Bearing (central cylindrical part of the impeller) )
9 ... Suction port 10 ... Discharge port 11 ... Packing 12 ... Dynamic pressure generating groove

Claims (4)

An impeller having a large number of blades on the outer periphery of the cylindrical portion and having a rotor magnet on the inner periphery of the cylindrical portion, a motor stator that is provided on the inner peripheral side of the rotor magnet and that rotates the impeller, and the impeller And a separation plate that hermetically partitions the motor stator, and a pump casing having a suction port and a water discharge port for sucking and discharging liquid,
A pump for generating dynamic pressure by rotation of the impeller is provided on at least one of the outer peripheral surface of the central cylindrical portion of the impeller and the cylindrical surface of the separation plate facing the pump. . The pump according to claim 1,
A pump for generating dynamic pressure by rotation of the impeller is provided on at least one of the outer peripheral surface of the central cylindrical portion of the impeller and the cylindrical surface of the pump casing facing the pump. . The pump according to claim 1 or 2, wherein
The said resistor is comprised by the some groove | channel. The pump characterized by the above-mentioned. The pump according to claim 3, wherein
The pump is characterized in that the plurality of grooves are formed in a predetermined same shape and are arranged at predetermined predetermined intervals.

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