JPH09131038A - Pump motor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve position detecting accuracy, the attaching strength of a position detecting element, the number of parts and to improve assembling property. SOLUTION: A stator 21 is constituted of a stator core 22, a stator winding 23 and a stator molded part 24, which molding is obtained by these parts with resin. A rotor 31 is fitted with a rotor yoke 33 and a permanent magnet 34 a rotary shaft 32 by a rotor molding part 35. An impeller part 36 is formed at the upper part of the rotor molding part 35. In the stator 21, an approximately rectangular-shaped positioning recess part 37, which forms a recessed shape upward from the upper surface of an electric loading chamber 26, is formed. A position detecting element 40 is coupled with the positioning recess part 37 and positioned.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a pump motor including a brushless motor having a position detecting element.

[0002]

FIG. 7 shows an example of a conventional pump motor. On the inner peripheral surface of the motor frame 1, a stator 4 including a stator core 2 and a stator winding 3 is formed.
Is provided inside the pump chamber 5
The pump case portion 6 having the above is attached. Further, inside the motor frame 1, a circuit board 7 is arranged below the stator 4. A waterproof partition wall 8 is arranged on the inner peripheral surface side of the stator 4.

The rotor 9 is formed by resin-molding a rotor yoke 10 and a permanent magnet 11 on a rotary shaft 9a, and an impeller portion 13 located in the pump chamber 5 is formed in the molded portion 12. There is. The circuit board 7 has a position detecting element 1 for detecting the rotation position of the rotor 9.
4 is mounted, which is supported by a holder 15 and faces the permanent magnet 11. The pump motor having such a configuration is a brushless motor. A suction port 6a and a discharge port 6b are formed in the pump case portion 6, and the impeller portion 1 is rotated by rotating the rotor 8.
When 3 is rotated, fluid such as water is sucked through the suction port 6a and discharged through the discharge port 6b.

By the way, in the above-mentioned conventional structure, since the position detecting element 14 is attached to the circuit board 7, the position of the position detecting element 14 with respect to the permanent magnet 11 varies, and the position detecting accuracy deteriorates. Therefore, as described above, the holder 15 is provided to support the position detecting element 14. However, since the holder 15 is also attached to the circuit board 7, the holder 15 itself is also a permanent magnet. 11, there is a variation in position, and the position detection accuracy is generally poor. Moreover, the number of parts is large and assembly is poor. Further, since both the position detecting element 14 and the holder 15 are erected on the circuit board 7, there is a problem that the mounting strength is weak. Further, in the above-described conventional configuration, the above-mentioned waterproof partition wall 8 is provided so that the water flowing into the pump chamber 5 does not wet the stator 4, but this also increases the number of parts and further improves the assemblability. Becomes worse.

The present invention has been made in view of the above circumstances, and it is an object of the present invention to improve the position detection accuracy and the mounting strength of the position detecting element, and further, to improve the number of parts. (EN) Provided is a pump motor capable of reducing the number of components and improving the assemblability.

[0006]

According to the present invention, there is provided a stator core, a stator winding provided on the stator core, and a stator mold portion formed by resin-molding the stator core and the stator winding. A rotor having a permanent magnet, and a rotor mold portion in which this permanent magnet portion is resin-molded, the rotor facing the stator with a minute gap, and A pump case portion forming a pump chamber, an impeller portion provided in the rotor and located inside the pump chamber, and a position facing the permanent magnet portion of the stator mold portion do not communicate with the minute gap. It is configured to include the formed positioning recess and the position detection element fitted and positioned in the positioning recess.

According to the above means, since the stator itself is waterproofed by the stator mold portion formed by resin-molding the stator core and the stator winding, the waterproof partition wall is not required, and the number of parts is reduced and the assemblability is improved. It is possible to improve. Since the positioning recess is formed in the stator mold and the position detecting element is fitted and positioned in the positioning recess, the position detecting element is accurately positioned on the stator. Since the child has an accurate positional relationship with the rotor, the position detection element is eventually positioned accurately with the permanent magnet of the rotor, which improves the position detection accuracy and is supported by the stator. Because it will be in the form,
The mounting strength is high.

[0008]

BEST MODE FOR CARRYING OUT THE INVENTION A first embodiment of the present invention will be described below with reference to FIGS. First, the stator 21 will be described. The stator 21 is a stator core 22.
3 phase stator winding 23 is applied to these stator cores 22
The stator winding 23 is molded with resin.
A stator mold portion 24 is formed by the resin mold portion, and a rotor placement space 25 is formed in the center of the stator mold portion 24.
Is formed, and a bearing recess 25a is formed in the center of the bottom. An electrical equipment room 26 is formed in the lower part.

Further, a pump case portion 27 is screwed and watertightly attached to the upper portion of the stator mold portion 24, and the pump case portion 27 communicates with the rotor placement space portion 25 inside. A pump chamber 28 is formed, and a suction port 27a is formed in the upper part and a discharge port 27b is formed in the side part. Furthermore, a bearing portion 30 is formed in the inner central portion through a support piece portion 29.

The rotor 31 has a rotating shaft 32 and a rotor yoke 3 attached thereto.
3 and the permanent magnet 34 are attached by resin molding, and the resin molding portion forms the rotor molding portion 35. An impeller portion 36 is formed on the rotor mold portion 35.
The rotor 31 is rotatably provided with the lower end and the upper end of a rotary shaft 32 being supported by the bearing recess 25a and the bearing 30. In this case, the rotor mold is provided in the rotor placement space 25. A portion of the permanent magnet 34 in the portion 35 is arranged with a minute gap G, and the impeller portion 36 is arranged in the pump chamber 28.

Now, the stator 21 has a substantially rectangular positioning recess 37 which is recessed upward from the upper surface of the electrical equipment chamber 26.
3 are formed, the positioning recesses 37 are separated by a predetermined angle (in this case, a mechanical angle of 60 °), and are not in communication with the minute gaps G. This positioning recess 37
The upper end of the above corresponds to the side surface of the permanent magnet 34 of the rotor 31. In addition, on the inner surface of the rotor placement space 25,
Cooling recesses 38, which are located between the positioning recesses 37 and communicate with the minute gap G and the pump chamber 28, are formed.

On the other hand, on the upper surface of the electrical equipment room 26, the circuit board 3
9 is attached thereto, and three position detecting elements 40 are mounted in an upright state. Each position detection element 40
Are fitted and positioned in the positioning recesses 37, and correspond to the side surfaces of the permanent magnet 34 in this state.

The pump motor having the above structure is a brushless motor, and the three-phase stator winding 23 has the position detecting element 40.
The rotor 31 is rotated by turning on / off the power at an appropriate timing based on the position detection signal by the rotor, and the impeller portion 36 is rotated by this, so that fluid such as water is sucked into the suction port 27.
It is sucked from a and discharged from the discharge port 27b. At this time,
Part of the water flows into the cooling recess 38 through the minute gap G,
As a result, the position detecting element 40 is cooled.

According to the present embodiment described above, the stator core 2
2 and the stator winding 23 are resin-molded with a stator mold portion 24, so that the stator 21 itself is waterproofed.
The conventional waterproof partition is unnecessary, and the number of parts can be reduced and the assemblability can be improved. Since the positioning recess 37 is formed in the stator mold portion 24 and the position detecting element 40 is fitted and positioned in the positioning recess 37, the position detecting element 40 is accurately positioned on the stator 21. Since the stator 21 has an accurate positional relationship with the rotor 31, the position detecting element 40 eventually becomes
The rotor 31 is accurately positioned with respect to the permanent magnet 34, the position detection accuracy is improved, and the stator 21 is supported, so that the mounting strength is increased.

Further, according to this embodiment, the stator mold portion 24 is adjacent to the positioning recess 37 and has a minute gap G.
Since the cooling recess 38 communicating with the pump chamber 28 is formed through the position detecting element 4
0 is maintained in a substantially constant temperature state, whereby the detection accuracy of the position detection element 40 is always stable.

4 and 5 show a second embodiment of the present invention. In this embodiment, the following points are different from the first embodiment. That is, the positioning recess 41 has a space 41a for accommodating the auxiliary yoke on the rear side of the position detecting element 40.
The auxiliary yoke 42 made of a magnetic material is inserted and disposed in the space 41a, and thus the auxiliary yoke 42 is provided on the opposite side of the position detecting element 40 from the permanent magnet 34. According to the second embodiment, the magnetic flux density passing through the position detecting element 40 is increased, and the position detecting accuracy is further improved.

FIG. 6 shows a third embodiment of the present invention. The third embodiment differs from the second embodiment in the following points. The positioning recess 51 is formed in the stator mold portion 24 so as to face the lower end surface of the permanent magnet 34.
The positioning recess 51 is arranged so as to face the lower end surface of
Is fitted and positioned. In this case, the auxiliary yoke 42 is attached to the position detecting element 40 on the side opposite to the permanent magnet 34. In this embodiment as well, the same effect as in the second embodiment can be obtained, and the positioning recess 51 can be formed without considering the position of the stator winding 23 so much. Will get better.

[0018]

As apparent from the above description, the present invention has the following effects. According to the invention of claim 1, since the stator core and the stator winding are resin-molded with the stator mold portion, the stator itself is waterproofed.
No waterproof partition is required, and the number of parts can be reduced and the assemblability can be improved. Since the positioning recess is formed in the stator mold and the position detecting element is fitted and positioned in the positioning recess, the position detecting element is accurately positioned on the stator. Since the position detecting element is accurately positioned with respect to the permanent magnet of the rotor, the position detecting accuracy can be improved, and moreover, the position supporting element is supported by the stator, so that the mounting strength can be increased.

According to the second aspect of the present invention, since the stator mold portion is formed with the cooling concave portion which is adjacent to the positioning concave portion and communicates with the pump chamber through the minute gap, the position is maintained even when heat is generated during motor operation. The detection element can be maintained in a substantially constant temperature state, and the detection accuracy of the position detection element can be stabilized.

According to the third aspect of the invention, since the auxiliary yoke made of a magnetic material is provided on the side of the positioning recess on the side opposite to the permanent magnet of the position detecting element, the magnetic flux density passing through the position detecting element is increased and the position detecting accuracy is increased. Is further improved.

According to the fourth aspect of the present invention, the positioning recess is formed so as to face the end surface of the permanent magnet, and the position detecting element is positioned so as to face the end surface of the permanent magnet. It becomes possible to form the positioning recess without paying much attention to the position of the line, which improves manufacturability.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional side view showing a first embodiment of the present invention.

FIG. 2 is a cross-sectional plan view of a main part of a stator

FIG. 3 is a cutaway side view of a cooling recess portion.

FIG. 4 is a vertical sectional side view showing a second embodiment of the present invention.

FIG. 5 is a diagram corresponding to FIG. 2;

FIG. 6 is a view corresponding to FIG. 3 showing a third embodiment of the present invention.

FIG. 7 is a half-broken side view showing a conventional example.

[Explanation of symbols]

21 is a stator, 22 is a stator core, 23 is a stator winding,
24 is a stator mold part, 27 is a pump case part, 28
Is a pump chamber, 31 is a rotor, 33 is a rotor yoke, 34
Is a permanent magnet, 35 is a rotor mold part, 36 is an impeller part, 37 is a positioning recess, 38 is a cooling recess, 40 is a position detecting element, 41 is a positioning recess, 42 is an auxiliary yoke, 5
Reference numeral 1 indicates a positioning recess.

Claims (4)

[Claims] 1. A stator having a stator iron core and a stator winding provided on the stator iron core, and a stator molding portion formed by resin-molding the stator iron core and the stator winding. A pump case part having a permanent magnet and a rotor mold part in which the permanent magnet part is resin-molded, and the rotor facing the stator with a minute gap, and a pump chamber formed inside An impeller portion provided in the rotor and located in the pump chamber, and a positioning recess formed at a position facing the permanent magnet portion of the stator mold portion so as not to communicate with the minute gap, A pump motor, comprising: a position detection element that is fitted into the positioning recess and positioned. 2. The minute gap communicates with the pump chamber, and the stator mold portion is formed with a cooling recess adjacent to the positioning recess and communicating with the pump chamber through the minute gap. The pump motor according to claim 1. 3. The pump motor according to claim 1, wherein the positioning recess is provided with an auxiliary yoke made of a magnetic material on the side of the position detecting element opposite to the permanent magnet. 4. The positioning recess is formed so as to face the end face of the permanent magnet, and the position detecting element is positioned so as to face the end face of the permanent magnet.
Pump motor described.