JPH0550099U - Canned motor pump - Google Patents

Abstract

(57) [Summary] (Modified) [Purpose] A canned motor pump provided with a rotor composed of a permanent magnet and a rotor yoke, and a pump chamber in which an impeller rotatably supported and integrally supported is arranged. In the above, the structure is such that the fixing strength between the rotor and the boss portion of the impeller is improved and, in addition, the air remaining between the partition wall and the rotor is easily discharged. [Structure] A longitudinal groove 9-2 is formed on the outer peripheral surface of a boss portion 9-1 which is integral with the impeller 9, and a groove is formed on the inner peripheral surface of a rotor yoke 11 fixedly arranged on the outer peripheral surface of the boss portion. A vertical protrusion 16 is formed so as to fit with 9-3, and both are fitted to hold and fix the rotor to the boss portion. Further, an axial groove is formed on the inner peripheral surface of the boss portion that is integral with the impeller, the axial groove penetrating the central portion of the impeller as well, so that ventilation between the rotor chamber 4 and the pump chamber 8 is facilitated. .

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a canned motor pump, particularly a canned motor pump suitable for a hot water circulation pump and the like.

[0002]

[Prior Art]

 FIG. 4 is a cross-sectional view showing a structural example of a conventional canned motor pump. In the canned motor pump shown in FIG. 4, windings are mounted in a stator chamber 3 in a space surrounded by an inner peripheral surface of a motor casing 2 and an outer peripheral surface of a cylindrical portion of a partition wall 5 having a bottomed cup shape. A stator 1 is provided, and the partition wall 5 and the pump casing 6 are pressure-bonded to each other via a seal member such as an O-ring 7 to form a pump chamber 8 that is shielded from the outside air except for a hot water inlet / outlet 18. A rotor chamber 4 is integrally formed in the chamber 8, and a cylindrical rotor yoke 11 and a permanent magnet 10 are integrated with the rotor cover 12 to form a rotor 19 and are arranged therein. There is. The boss portion 9-1 which is integral with the impeller 9 arranged in the pump chamber 8 has a cylindrical shape, and the cylindrical portion is inserted into the inner surface of the rotor 19 and fixed by a fixing means such as adhesion. The rotor 19 is fixedly held, and bearings 13 are fitted to both ends of the inner peripheral surface of the boss portion 9-1. A shaft 14 for rotatably supporting the rotor 19 and the impeller 9 integral with the rotor 19 is provided with one shaft holding portion 5-2 formed at the center of the bottom surface 5-1 of the partition wall 5 and the shaft holding portion 5-2. It is fixed at the center of the pump casing 6 by the other shaft holding portion 6-2 held by a plurality of legs 6-1.

A rotating magnetic field is generated on the inner peripheral surface of the stator 1 by energizing it by a control circuit (not shown) separately provided for the winding 1-1 mounted on the stator 1, and a cylindrical partition wall is formed. It drives the rotor 19 which is concentrically and rotatably supported by the parts 5-3, and thus drives the impeller 9 which is integral with the rotor 19 and functions as a pump. is there. In the above-mentioned configuration, as is well known, the stator chamber 3 on the side of the stator 1 which is an energization unit and the pump chamber 4 through which the hot water flows are separated by the partition wall 5, so that the warm water affects the insulation of the stator. There is nothing.

[0004]

[Problems to be solved by the device]

 In the conventional structure as described above, since the impeller 9 and the boss portion 9-1 integral therewith are formed of resin, the resin member is not suitable for adhesion and the outer periphery of the boss portion 9-1 is not formed. Due to the difference in the coefficient of thermal expansion due to the difference in material between the rotor yoke 11 which is fixed to the surface and is formed of a magnetic material, the reliability of fixing and holding the both is insufficient.

Further, the impeller 9 and the rotor 19 integral therewith form the rotor chamber 4 except for a narrow gap between the inner peripheral surface of the cylindrical portion 5-3 of the partition wall and the outer peripheral surface of the rotor 19. Because of the semi-shielded state, there is a problem that it is difficult to discharge the air accumulated in the narrow space between the bottom surface 5-1 of the partition wall 5 and the rotor 19 by the operation of the pump.

[0006]

[Means for Solving the Problems]

 The canned motor pump according to the present invention is rotated by fitting the axial groove on the outer peripheral surface of the boss portion, which is integral with the impeller, and the axial projection on the inner peripheral surface of the rotor yoke arranged therein. An axial groove that also penetrates the center of the impeller so that the child is held and fixed and is located in the middle of the groove on the outer surface of the boss that is integral with the impeller. Is formed.

[0007]

[Work]

 In the above structure, the boss and the rotor yoke, which are made of different materials, are joined by fitting the groove and the protrusion of the both, so that the reliability of the fixing strength between the two is increased and the inner circumference of the boss is increased. The groove that penetrates the surface facilitates ventilation between the inner side of the rotor chamber near the bottom of the partition wall and the impeller side, which is effective in discharging air accumulated in the rotor chamber.

[0008]

【Example】

 An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a sectional view showing an example of a canned motor pump according to the present invention. The difference from the conventional example of FIG. 4 is that the structure of a boss portion 9-1 for holding a rotor and the structure of the boss portion 9-1 It is the structure of the joint part. FIG. 2 is a transverse cross-sectional view of the rotor 19 of the portion supported by the bearing 13 of the example shown in FIG. 1, which is integrated with the impeller 9 as is apparent from the exploded views of the rotor 19 of FIGS. 1 and 3. The axial groove 9-2 is formed on the outer peripheral surface of the boss portion 9-1, which is formed so as to extend to the inner peripheral surface of the rotor 19, and the rotor yoke 11 fitted in the groove 9-2 is formed. An axial protrusion 16 is formed on the inner peripheral surface. Since these grooves 9-1 and the protrusions 16 are fitted into each other so as to be intricately mounted in the mounted state and the gap is applied and filled with the adhesive 20, the bosses 9-1 are hard to be adhered with resin. In addition to the above, the other rotor yoke 11 has a different coefficient of thermal expansion of a magnetic material, which compensates for the decrease in reliability of the fixing strength against thermal stress.

Further, a groove 9-3 is formed on the inner peripheral surface fitted into the bearing 13, and the groove 9-3 penetrates to the outer surface of the impeller 9 on the pump chamber 8 side. The outer groove 9-3 assists ventilation between the rotor chamber 4 near the bottom surface 5-1 of the partition wall and the pump chamber on the impeller 5 side, and is therefore effective in discharging the air accumulated in the rotor chamber 4. is there.

[0010]

[Effect of the device]

 Since the canned motor pump according to the present invention is configured as described above, the reliability of retaining the fixing strength between both the boss portion and the rotor yoke, which are made of different materials, is improved, and the groove penetrating the inner peripheral surface of the boss portion has a partition wall. Since it facilitates the passage of air between the impeller side and the back of the rotor chamber near the bottom surface, it has the effect of facilitating the discharge of the air accumulated in the rotor chamber.

[Brief description of drawings]

FIG. 1 is a sectional view showing an example of the structure of a canned motor pump according to the present invention.

FIG. 2 is a cross-sectional view of a main part of the rotor of the example shown in FIG.

3 is an exploded view of a portion of an impeller and a rotor of the example shown in FIG.

FIG. 4 is a sectional view showing an example of a conventional canned motor pump.

[Explanation of symbols]

 1: Stator 2: Motor casing 3: Stator chamber 4: Rotor chamber 5: Partition wall 5-1: Bottom surface 5-2: One shaft holding portion 5-3: Cylindrical portion 6: Pump casing 6-1: Multiple Foot 6-2: Other shaft holding part 7: O-ring 8: Pump chamber 9: Impeller 9-1: Boss part 9-2: Groove on outer peripheral surface of boss 9-3: Groove on inner peripheral surface of boss 10 : Permanent magnet 11: Rotor yoke 12: Rotor cover 13: Bearing 14: Shaft 15: Collar 16: Projection on the inner peripheral surface of the rotor yoke 17: Adhesive pool on the outer peripheral surface of the rotor yoke 18: Hot water inlet / outlet 19 : Rotor 20: Adhesive

Claims (3)

[Scope of utility model registration request] 1. A motor casing, which has a cup-shaped internal partition wall and a pump casing, and is fixed by winding a winding in a space surrounded by an inner peripheral surface of the motor casing and an outer peripheral surface of the partition wall. A rotor having at least a permanent magnet and a rotor yoke in a space surrounded by a stator chamber in which a child is arranged, an inner peripheral surface of the partition wall and an inner side surface of the pump casing; In a canned motor pump including a pump chamber in which an impeller rotatably supported and rotatably supported is arranged, an axial groove is formed on an outer peripheral surface of a boss portion that is integral with the impeller, and one of the outer peripheral surface of the boss portion An axial projection that fits into the groove of the boss portion is formed on the inner peripheral surface of the rotor yoke that is arranged and fixed, and both are fitted to hold and fix the rotor to the boss portion. A canned motor pump that is characterized. 2. The canned motor pump according to claim 1, wherein an axial groove is formed on an inner peripheral surface of a boss portion that is integral with the impeller and that also penetrates a central portion of the impeller. 3. The canned motor according to claim 2, wherein a groove on the inner peripheral surface of the boss portion which is integral with the impeller is formed at an intermediate position of the groove provided on the outer peripheral surface thereof. pump.