KR100274716B1 - A single-phase induction motor and rotor assembling apparatus - Google Patents

Abstract

An object of the present invention is to suppress the generation of electronic noise even in a high load high torque operation (when the capacity of a driving capacitor is large) in an electric motor.

The present invention relates to a main winding (2), an auxiliary winding (3) provided at a position different from the main winding (2) and an electrical angle, and a plurality of driving capacitors (4) connected to the auxiliary winding (3). And 6), a relay 5 for turning on and off the driving capacitor 6 in accordance with the operating load, and a rotor in which the gap side (outer peripheral side) of the slot is opened.

Description

A single-phase induction motor and rotor assembling apparatus}

The present invention relates to a single-phase induction motor of a hermetic compressor used in a refrigerator or an air conditioner.

11 is a cross-sectional view of the rotor 9 of the conventional single-phase induction motor shown in, for example, Japanese Utility Model Publication No. 58-172015, where reference numeral 9a denotes a rotor outer circumference and reference numeral 12 denotes. As a closed space in the rotor 9, aluminum is a die-cast slot portion, numeral 13 is a tooth between each slot portion 12, and numeral 14 is a rotor outer circumference portion 9a. It is a bridge connecting the teeth 13 on the side.

12 is a cross-sectional view of the rotor 9 of the conventional single-phase induction motor shown in Japanese Patent Laid-Open No. 60-39352, where reference numeral 9 denotes a rotor, reference numeral 9a denotes a rotor outer circumference, and reference numeral 12 Is a slot part, code | symbol 12a is a slot opening part, code | symbol 13 is a tooth | gear.

In the rotor 9 shown in FIG. 11, the slot part 12 constitutes a closed space in the rotor 9, and aluminum is die-cast in the center (the shape of the slot part 12 is generally closed. Called a closed slot). In other words, the bridge 14 which connects the tooth 13 exists between each slot part 12 and rotor outer peripheral part 9a. The narrower the bridge 14 is, the better the motor efficiency is. On the other hand, the narrow bridge 14 generates magnetic saturation and generates electronic noise. In particular, during the high torque operation of the large capacity of the operation capacitor, a large electronic sound is generated.

In addition, in the rotor 9 shown in FIG. 12, the bridge 14 connecting the teeth 13 between each slot 12 and the rotor outer peripheral portion 9a does not exist, and the slot opening 12a is provided. As an example of the slot, aluminum is ejected from the slot opening 12a to the outer periphery in the aluminum die cast step after lamination to the rotor core, so the outer periphery of the rotor 9 must be cut or buffered after die casting.

Since the conventional single phase induction motor is configured as described above, there are the following problems.

(1) In the closed slot rotor 9, the bridge 14 is narrow during high-torque operation in which the capacity of the driving capacitor is large, so that it is easy to self-saturate, and electromagnetic noise is generated and the noise is high.

(2) Since the rotor 9 of the open slot is blown out to the outer circumference from the slot opening 12a in the aluminum die casting step, the outer circumference of the rotor 9 must be cut or buffered after die casting.

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems, and provides a single-phase induction motor capable of suppressing the generation of electronic sound even during high torque operation with a large capacity of operation capacitor. It is an object of the present invention to provide a rotor assembly apparatus in which aluminum is not ejected from the slot opening at the time and the cutting or buffering of the outer circumference of the rotor after die casting is unnecessary.

1 is a circuit diagram of a single phase induction motor according to Embodiment 1 of the present invention.

2 is a diagram showing electronic sound data of a single-phase induction motor according to Embodiment 1 of the present invention.

3 is a diagram showing frequency analysis data of electronic sounds of a single-phase induction motor according to Embodiment 1 of the present invention.

4 is a diagram showing frequency analysis data of electronic sounds of a single-phase induction motor according to Embodiment 1 of the present invention.

Fig. 5 is a sectional view of the rotor core assembly when inserting the rotor assembly according to the second embodiment of the present invention.

6 is a cross-sectional view of a rotor assembly device according to Embodiment 2 of the present invention.

Fig. 7 is a sectional view of the rotor core assembly during the rotor assembly according to the second embodiment of the present invention.

8 is a flowchart of a rotor core assembly of the rotor assembly apparatus according to Embodiment 2 of the present invention.

9 is a sectional view of a rotor assembly according to Embodiment 3 of the present invention.

10 is a flowchart of the rotor core assembly of the rotor assembly apparatus according to Embodiment 3 of the present invention.

11 is a cross-sectional view of a rotor (closed slot) of a conventional single phase induction motor.

12 is a cross-sectional view of a rotor (open slot) of a conventional single phase induction motor.

* Explanation of symbols for main parts of the drawings

1: single phase induction motor 2: main winding

3: auxiliary winding 4,6: driving capacitor

5: relay 9: rotor

12: slot 12a: slot opening

The rotor assembly of claim 1 is a bush 16 in which the rotor core assembly 15 is axially inserted during die-casting, the rotor core assembly 15 having slots for receiving diecast conductors. (12), wherein the rotor core assembly (15) has molten metal in the bush (16) and the rotor core assembly (15) when the slots are connected to the outer periphery of the assembly by a slot opening (12a). The bush (16) in close contact with the bush (16) such that it cannot be ejected from the gap between the bushes and the rotor core assembly can be taken out after diecasting; And A core band 19, having a gap in the circumferential direction of the bush 16 between the core band 19 and the bush 16, and fits with the bush 16 so that movement in the axial direction is limited. Physics includes the core band 19.

The rotor assembly of claim 2 comprises an oil pressure chuck 20 into which the rotor core assembly 15 is inserted during die-casting, the core assembly 15 having diecast conductors. Having slots 12 for receiving, the gap between the rotor core assembly 15 and the hydraulic chuck 20 is made larger by reducing the hydraulic pressure during insertion of the rotor core assembly 15, the gap being a die During the cast, when the slots 12 are connected to the outer circumference of the assembly by the slot opening 12a, it is narrowed by increasing the hydraulic pressure so that molten metal cannot be ejected from the gap.

(Embodiment 1)

Next, Embodiment 1 of the present invention will be described. 1 is a circuit diagram of a single phase induction motor according to Embodiment 1 of the present invention. In the drawing, reference numeral 1 denotes a single-phase induction motor, reference numeral 2 denotes a main winding wound around a stator of the motor 1, reference numeral 3 denotes an equal auxiliary winding, and reference numeral 4 denotes an electric current of the electric motor 1 The first driving capacitor which is always energized, the second driving capacitor which is energized only in the high torque operation and the second operating capacitor which is separated from the relay 5 in the low torque operation, the sign 7 is the starting capacitor, and the sign 8 is It is a PTC thermistor which is a starting relay which isolates the starting capacitor 7 immediately after starting.

Electronic sound when the single slot induction motor shown in FIG. 1 uses the rotor of an open slot (FIG. 12) or the rotor of a closed slot (FIG. 11) is demonstrated. Fig. 2 is a diagram showing the test results, in the low torque operation (only the first driving capacitor 4 is energized when the relay 5 is off), and in the high torque operation (the relay 5 is on, the first operating capacitor is ON). (4) and the second driving condenser (6) are both energized) that the rotor side of the open slot has a smaller beep than the rotor of the closed slot, and in particular, the difference between the rotor and the rotor of the open slot is high Test results were obtained.

3 and 4 are sound data when the width of the slot opening 12a of the rotor 9 is changed, and as shown in FIG. 4, when the width is 1 mm or more, the electronic sound near 400 Hz is reduced from the closed slot. Although the electronic sound due to the home high frequency around 1000Hz is slightly increased, the open slot side is low level at the total level. Fig. 3 shows the test results at a width of 0.5 mm. As shown in Fig. 3, when the width of the slot opening 12a is 0.5 mm, the overall open slot side has a smaller beep, especially a beep around 400 Hz. .

The electronic sound at issue in the present invention is a sound belonging to a so-called low frequency sound around 400 Hz, which radiates from the surface of the compressor and passes through the refrigerator main body. Thus, the sound insulation effect is hardly obtained, and as a countermeasure, the sound source is lowered. The method is the most effective.

As described above, according to the first embodiment, the capacitance is increased to obtain high torque only during operation under high load, and the capacitance is obtained during operation under low load to obtain low torque. Very good, high efficiency operation. In addition, since the slot opening 12a which does not exist the bridge | bridging 14 which connects the tooth | gear 13 between each slot part 12 and the rotor outer peripheral part 9a is provided, the high load operation at the time of high load operation is provided. Also, the magnetic saturation does not occur, the generation of electronic sound is suppressed, and a single-phase induction motor with low noise is obtained.

(Embodiment 2)

Next, Embodiment 2 of the present invention will be described. FIG. 5 is a view showing a method of inserting a rotor core assembly into a bush in the rotor assembly method according to Embodiment 2 of the present invention, FIG. 6 is a sectional view of the die cast mold, and FIG. 7 is the rotor core assembly. The figure which shows the state which draws out from a bush. In the figure, reference numeral 15 denotes a rotor core assembly in which a rotor perforated steel sheet of an open slot is laminated, reference numeral 16 denotes a bush into which the rotor core assembly 15 is inserted during die casting, and reference numeral 16a denotes a bush 16. Is formed in the outer circumference of the core, reference numeral 17 is a movable frame, numeral 18 is a fixed frame, numeral 19 is a core band fitted with a gap in the outer diameter of the bush 16, numeral 19a is a core It is a protrusion that engages the recess 16a of the bush 16.

8 is a flowchart of the rotor assembly method. In step 30, the core assembly 15 is inserted into the bush 16, and in step 31, the movable frame 17 and the fixing frame 18 are brought into close contact with both ends of the core assembly 15. After positioning by applying a load to the movable frame 17 in step 32, diecasting is performed in step 33, and only the rotor is taken out in step 34.

In the figure, the inner diameter of the core band 19 and the outer diameter of the bush 16 are fitted with a certain gap, but since the protrusions of the inner diameter of the core band 19 and the recesses of the outer diameter of the bush 16 are engaged with each other, the core Even if the axial force acts on the bush 16 by the frictional force when the assembly 15 is inserted into the bush 16, the bush 16 does not escape (in addition to the inner diameter of the core band 19). There is a recess, and there is a projecting portion in the outer diameter of the bush 16, and the same effect is obtained even if they are engaged with each other).

By reducing the gap between the core assembly 15 and the bush 16, aluminum is not ejected between the core assembly 15 and the bush 16 during die casting, and can be easily taken out after die casting. Since aluminum is not ejected from the core assembly 15 to the bush 16 as described above, the rotor 9 of the open slot can be manufactured without cutting or buffering the outer periphery of the rotor 9 after diecasting, and The cost can be greatly reduced compared to buffering. In addition, since the bush 16 is fixed to the die-casting machine together with the core band 19, the bush 16 is always one, and the compression-installation precision is easily stabilized, and since only the rotor 9 is taken out, It is excellent and easy to automate.

(Embodiment 3)

Next, Embodiment 3 of this invention is demonstrated about drawing. FIG. 9 is a cross-sectional view showing the assembling structure of the hydraulic chuck system by the rotor assembling method according to the third embodiment of the present invention, and FIG. 10 is a flowchart of the rotor assembling method. The core assembly 15 is inserted inside the hydraulic chuck 20 in the core band 19 (step 40), and the movable frame 17 and the fixing frame 18 are brought into close contact with both ends of the core assembly 15, and When the hydraulic pressure of the hydraulic chuck 20 is increased (step 41), the gap between the core assembly 15 and the hydraulic chuck 20 is narrowed (step 42), and then aluminum is die cast (step 43). The hydraulic pressure of the hydraulic chuck 20 is lowered (step 44), and only the rotor is taken out (step 45), so that aluminum is not ejected from the outer peripheral portion 12a of the slot portion. The hydraulic chuck 20 can have a small internal diameter change by hydraulic pressure, and can make the clearance between the core assembly 15 and the hydraulic chuck 20 zero.

On the other hand, since the gap between the core assembly 15 and the hydraulic chuck 20 before the hydraulic lift is large, the core assembly 15 can be easily set to the hydraulic chuck 20, and aluminum is the core assembly 15 during die casting. ) And the hydraulic chuck 20 are not ejected, and after die casting, the hydraulic pressure can be lowered to easily take out. Since aluminum is not ejected between the core assembly 15 and the hydraulic chuck 20 as described above, the rotor 9 of the open slot can be manufactured without cutting or buffering the outer circumference of the rotor 9 after diecasting, and cutting Alternatively, the cost can be greatly reduced compared to buffering. In addition, setting of the core assembly 15 is very easy, machining time can be shortened, machining cost can be reduced, and there are no parts to be worn as compared with the case where the bush 16 is fitted, and the durability of the jig is improved. This is improved.

The rotor assembly apparatus of Claim 1 has the bush which inserted the rotor core assembly at the time of aluminum die-casting, and reduced the clearance gap with the rotor core assembly to the limit which takes out the rotor core assembly after aluminum die-casting, and this bush is radially attached to this bush. Since the core band has a certain gap and a core band fitted with limited movement in the axial direction, the cutting or buffer of the outer circumference after diecasting becomes unnecessary, and the bush is fixed to the diecast machine. One bush is enough, excellent mass productivity and easy automation.

The rotor assembly apparatus of Claim 2 is installed inside the core band, and has a hydraulic chuck in which the rotor core assembly is inserted at the time of aluminum die casting, and the hydraulic chuck has a rotor core assembly before the hydraulic rise when the rotor core assembly is inserted. Since the gap between the and the die is large, and the hydraulic pressure is increased during die-casting, the gap is reduced, so that cutting or buffering of the outer circumference after the die-casting is unnecessary, and the setting of the rotor core assembly is easy, thereby reducing the machining cost and furthermore, jig) is improved in durability.

Claims (2)

In a device for assembling the rotor of a single-phase induction motor, A bush 16 into which the rotor core assembly 15 is axially inserted during die-casting, the rotor core assembly 15 having slots 12 for receiving diecast conductors, the rotor The core assembly 15 allows molten metal to be ejected from the gap between the bush 16 and the rotor core assembly 15 when the slots are connected to the outer periphery of the assembly by a slot opening 12a. The bush (16) in close contact with the bush (16) such that the rotor core assembly can be taken out after diecasting; And A core band 19, having a gap in the circumferential direction of the bush 16 between the core band 19 and the bush 16, and fits with the bush 16 so that movement in the axial direction is limited. The rotor assembling apparatus provided with the said core band 19 for physics. In the apparatus for assembling the rotor of a single-phase induction motor, An oil pressure chuck 20 into which the rotor core assembly 15 is inserted during die-casting, the core assembly 15 having slots 12 for receiving diecast conductors. And the gap between the rotor core assembly 15 and the hydraulic chuck 20 is made larger by reducing the hydraulic pressure during insertion of the rotor core assembly 15, the gap being, during diecast, the slots 12. ) Is further narrowed by increasing the hydraulic pressure so that molten metal cannot be ejected from the gap when connected to the outer circumference of the assembly by a slot opening (12a).