Sealed electric-motor and sealed pump

Abstract

The present invention provides an inexpensive canned motor which is efficient as a motor and is little in dispersion of performance. In this canned motor (50) which has a can (52) for isolating and sealing the stator core (60) of a DC brushless motor from a rotor magnet (68), the can (52) has a core positioning part (62) which positions the stator core (60) in the rotational direction of the rotor magnet (68) and a sensor positioning part (76) which positions the magnetic sensor (74) for detecting the magnetic pole of the rotor magnet (68), in the rotational direction of the rotor magnet (68). It is to be desired that the above core positioning part (62) should be recessed. Moreover, it is to be desired that the above sensor positioning part (76) should be recessed in parallel with the rotating shaft of the rotor magnet (68), or recessed in parallel with a sensor board for mounting a magnetic sensor (74).

Description

technical field [0001] The present invention relates to a hermetic motor and a hermetic pump, and more particularly, to a hermetic motor and hermetic pump having a tank that seals a stator core of a DC brushless motor away from a rotor magnet. Background technique [0002] As a pump that pressurizes and discharges fluid for supplying hot water or water, there is known a hermetic pump in which the rotor magnet and the impeller of the motor are housed in the pump chamber in an integrated structure, and are shielded by the fluid The stator core of the motor is arranged at the position of the partition wall (tank body). Conventionally, such sealed pumps generally use an AC motor with a simple structure, but a sealed pump using a DC motor is being developed in response to a demand for power saving (for example, Patent Document 1). [0003] FIG. 4 is a cross-sectional view of the hermetic pump shown in Patent Document 1. FIG. The sealed pump shown in Fig. 4 comprises: the rotor ...

AI Technical Summary

Problems solved by technology

In particular, if the positional relationship between the stator 10 and the magnetic sensor 20 deviates from the design value, the performance of the motor will be greatly reduced, and the efficiency of the pump will deteriorate.

[0008] In the hermetic pump described in the conventional patent document 1, the magnetic sensor 20 is mounted on the substrate of the control unit 12, so the installation error between the control unit 12 and the stator 10, the installation error between the control unit 12 and the magnetic sensor 20, The inclination errors of the mounted magnetic sensor 20 add up, deteriorating the performance of the motor, and causing a problem in which the specified pump performance cannot be obtained.

In addition, when it is applied to a servo motor that is used by switching the rotation direction, the installation error of the stator 10 and the magnetic sensor 20 will appear as a difference in the torque performance of each rotation direction, so it is not good.

[0009] In addition, in order to maintain the performance of the pump, adjustments can be made during the assembly process to reduce the installation error between the control unit 12 and the stator 10, the installation error between the control unit 12 and the magnetic sensor 20, and the inclination error of the installed magnetic sensor 20. However, this will increase the assembly and adjustment process, and there is a disadvantage that the price of the pump will increase.

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