JP2006283694A - Scroll type fluid machine - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a scroll type fluid machine improving suction efficiency of a scroll unit without causing enlargement and increase of number of components. <P>SOLUTION: The scroll type fluid machine is used as a compressor. A spiral groove 64 is provided on an outer circumference surface of a rotor 54 of an armature thereof. The spiral groove 64 opens on both surfaces of the rotors 54 and increases effective flow passage cross section area of refrigerant route introducing refrigerant to a scroll unit. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a scroll type fluid machine, and more particularly to a scroll type fluid machine suitable as a scroll compressor for a refrigeration circuit for a vehicle air conditioning system.

When the scroll fluid machine is used as the scroll compressor of the refrigeration circuit described above, the scroll compressor is driven by a vehicle engine or an electric motor. In the case of an electric scroll compressor, the amount of refrigerant discharged from the compressor can be easily adjusted regardless of the engine load, which is suitable for finely controlling the air conditioning temperature in the passenger compartment.
Therefore, a scroll compressor integrated with an electric motor is known (see, for example, Patent Document 1). Such a scroll compressor includes a scroll unit and a scroll unit housed together in the housing. While the armature is provided, the coolant is returned to the scroll unit through the armature to cool the armature.

  Therefore, a refrigerant path reaching the scroll unit through the motor is secured in the housing. Specifically, the refrigerant path includes an air gap between the rotor and the stator in the armature, a gap between the stator and the housing inner peripheral surface, and a gap between the stator coils, all of which are narrow. . For this reason, the pressure loss of the refrigerant flowing through the refrigerant path is large, and the refrigerant suction efficiency of the scroll unit is deteriorated.

In order to solve the above-mentioned problems, as disclosed in Patent Document 2, while an axial passage is formed in the rotor, fans are attached to both end faces of the rotor, and the rotation of these fans causes the axial direction. The refrigerant flowing through the passage may be forcibly generated.
JP 2003-129983 A JP 2002-165406 A

However, when the cooling technology of Patent Document 2 is adopted for the scroll compressor, the diameter of the rotor is increased by an amount corresponding to the axial passage. As a result, the scroll compressor becomes large and its weight also increases. . Further, if fans are provided on both end faces of the rotor, the number of parts increases and the cost of the scroll compressor increases.
The present invention has been made based on the above-described circumstances, and an object of the present invention is to provide a scroll type fluid machine that can increase the suction efficiency of the scroll unit without increasing the size or increasing the number of parts. There is to do.

  In order to achieve the above object, a scroll type fluid machine according to the present invention includes a housing, an armature housed in the housing together with the scroll unit and driving the scroll unit, and secured in the housing. The fluid path includes a spiral groove provided on the outer peripheral surface of the rotor of the armature and opened at both end faces of the rotor, respectively (Claim 1).

  According to the scroll type fluid machine described above, when the scroll unit is driven by the motor, the scroll unit sucks the working fluid guided through the fluid path, and the pressure of the sucked working fluid is changed. Discharged from the unit. As the rotor rotates, the working fluid in the spiral groove receives a force in the axial direction of the rotor, and a flow of the working fluid toward the scroll unit is forcibly generated in the spiral groove.

Specifically, the scroll unit is a compression unit for the refrigeration circuit, and the fluid path is a refrigerant path for returning the refrigerant to the compression unit (claim 2). In this case, the refrigerant flowing through the refrigerant path is supplied to the compression unit after cooling the armature.
The rotor is composed of a laminate of electromagnetic steel sheets having notches on the outer periphery, and has a spiral groove in which notches of individual electromagnetic steel sheets are connected (Claim 3), or has a spiral groove formed on the outer peripheral surface of the laminate. (Claim 4).

  Since the scroll type fluid machine according to claims 1 to 4 is provided with a spiral groove on the outer peripheral surface of the rotor, the effective fluid cross-sectional area of the working fluid is increased by the amount of the spiral groove. The pressure loss of the working fluid can be reduced. Moreover, since the working fluid is forced to flow through the spiral groove, the suction efficiency of the scroll unit is greatly improved by the pressure loss reduction and the supercharging effect of the working fluid. In the scroll fluid machine according to the second aspect, the armature can be effectively cooled by the refrigerant flowing through the refrigerant passage, and the performance of the armature can be effectively maintained.

FIG. 1 shows a scroll compressor as a scroll type fluid machine, and this compressor is used as a compressor for a vehicle air conditioning system, that is, its refrigeration circuit.
The compressor includes a cylindrical housing 10, and the housing 10 includes a unit casing 12, a motor casing 14, and a circuit casing 16 in order from the left as viewed in FIG. 1. The unit casing 12 and the motor casing 14 and the motor casing 14 and the circuit casing 16 are both coupled to each other via a plurality of connecting bolts 18.

A scroll unit 20 is accommodated in the unit casing 12, and the scroll unit 20 has a fixed scroll 22 and a movable scroll 24. The movable scroll 24 is disposed on the motor casing 14 side, and the fixed scroll 22 is fixed to the end wall 12 a of the unit casing 12 via a plurality of fixing bolts 26.
The fixed and movable scrolls 22 and 24 are combined so that their spiral walls engage with each other, and a plurality of compression chambers 28 are formed between the spiral walls. The compression chambers 28 move toward the center of the fixed scroll 22 with the turning motion of the movable scroll 24 relative to the fixed scroll 22, and the volume is reduced in the moving process.

  A discharge chamber 30 is formed in the unit casing 12 between the fixed scroll 22 and its end wall 12 a, and a discharge hole 32 is formed through the center of the fixed scroll 22. The above-described compression chamber 28 is sequentially communicated with the discharge hole 32, and the discharge hole 32 is opened and closed by a discharge valve (not shown). This discharge valve is attached to the end face of the fixed scroll 22 on the discharge chamber 30 side.

Further, a discharge port 34 is formed on the outer peripheral wall of the unit casing 12, and this discharge port 34 communicates with the discharge chamber 30 and is connected to the refrigerant circulation path (not shown) of the refrigeration circuit described above.
The movable scroll 24 is rotated with respect to the fixed scroll 22 as described above by receiving power from the electric motor. At this time, the rotation of the movable scroll 24 is prevented. For this reason, a ball coupling 36 is disposed between the movable scroll 24 and the motor casing 14, and the ball coupling 36 functions to prevent the movable scroll 24 from rotating and to receive a thrust load from the movable scroll 24. This thrust load is transmitted to the motor casing 14 via the ball coupling 36.

The electric motor described above includes an armature 38 accommodated in the motor casing 14, and the armature 38 has a rotating shaft 40. The rotary shaft 40 extends from one end of the motor casing 14 to the circuit casing 16, and both ends of the rotary shaft 40 are rotatably supported by the motor casing 14 and the circuit casing 16 via bearings 42 and 44.
One end of the rotating shaft 40 is formed as a large-diameter end portion 46, and the large-diameter end portion 46 has an end surface exposed toward the inside of the unit casing 12. A crankpin 48 protrudes from the end surface of the large-diameter end 46 toward the movable scroll 24, and an eccentric bush 50 is attached to the crankpin 48. The eccentric bush 50 is rotatably supported by a boss 24 a of the movable scroll 24 via a needle bearing 52.

  Accordingly, when the rotary shaft 40 is rotated, the rotational force of the rotary shaft 40 is transmitted to the movable scroll 24 via the crank pin 48, the eccentric bush 50, and the needle bearing 52. As a result, the movable scroll 24 is moved to the ball coupling 36. The rotation of the fixed scroll 22 is performed in a state in which the rotation is prevented by the rotation of the fixed scroll 22, and the turning radius is determined by the inter-axis distance between the rotary shaft 40 and the crankpin 48.

The armature 38 has a rotor 54 attached to the rotary shaft 40, and the rotor 54 is surrounded by a stator 56. The stator 56 is fixed to the inner peripheral surface of the motor casing 14.
A suction port 58 is formed through the outer peripheral wall of the circuit casing 16. The suction port 58 is connected to the refrigerant circulation path of the refrigeration circuit described above, and allows the refrigerant from the refrigerant circulation path to flow into the circuit casing 16. A motor drive circuit 59 for the armature 38 is disposed in the circuit casing 16, and the motor drive circuit 59 controls the rotation of the armature 38 while supplying power to the armature 38.

The refrigerant that has flowed into the circuit casing 16 is guided into the unit casing 12 through a refrigerant path secured in the motor casing 14. Specifically, the refrigerant path includes an air gap Ga between the rotor 54 and the stator 56, a gap Gb between the inner peripheral surface of the motor casing 14 and the stator 56, and a gap (not shown) between the stator coils. It is out.
A portion in the unit casing 12 into which the refrigerant is introduced is formed as a suction chamber 60. The suction chamber 60 surrounds the movable scroll 24 of the scroll unit 20 and is partitioned by the fixed scroll 22 with respect to the discharge chamber 30.

  When the movable scroll 24 is swung and the compression chamber 28 is opened to the suction chamber 60, the compression chamber 28 sucks the refrigerant in the suction chamber 60. The sucked refrigerant is compressed in the process in which the compression chamber 28 moves toward the discharge hole 32 of the fixed scroll 22 as the movable scroll 24 rotates. When the compression chamber 28 reaches the discharge hole 32 and the pressure in the compression chamber 28 overcomes the shutoff pressure of the discharge valve, the discharge valve is opened, and the compressed refrigerant in the compression chamber 28 passes through the discharge hole 32 to the discharge chamber. 30 is discharged.

Thereafter, the compressed refrigerant is sent from the discharge chamber 30 to the refrigerant circulation path through the discharge port 34, reaches the suction port 58 through the condenser, receiver, expansion valve, evaporator and the like of the refrigeration circuit, and from this suction port 58. The refrigerant passes through the refrigerant path in the circuit casing 16 and the motor casing 14 and is returned to the suction chamber 60.
Since the refrigerant flowing through the refrigerant path of the motor casing 14 is returned from the evaporator, the temperature thereof is low and the armature 38 is effectively cooled, thereby preventing the armature 38 from being overheated.

As apparent from FIG. 1, the rotor 54 of the armature 38 is a laminated body made up of a number of electromagnetic steel plates 62, and as shown in FIG. 2, a spiral groove 64 is provided on the outer circumferential surface of the laminated body, that is, the rotor 54. It has been. The spiral groove 64 opens at both end faces of the rotor 54 and constitutes a part of the refrigerant path described above.
Specifically, in the case of the rotor 54 of one embodiment, as shown in FIG. 3, each electromagnetic steel plate 62 has a ring shape, and a notch 66 is formed on the outer peripheral surface thereof. When a laminated body is formed from the electromagnetic steel plates 62, the notches 66 of the individual electromagnetic steel plates 62 are connected to each other to form the spiral groove 64 described above.

  Since the spiral groove 64 described above increases the effective flow path cross-sectional area of the refrigerant path, the pressure loss of the refrigerant in the refrigerant path is reduced. Further, as the rotor 54 rotates, the refrigerant in the spiral groove 64 receives a force in the axial direction of the rotor 54, and the refrigerant flow toward the inside of the unit casing 12, that is, the suction chamber 60 is forced in the spiral groove 64. Is born. Therefore, not only the supercharging of the refrigerant into the suction chamber 60 is achieved, but also the cooling effect of the armature 38 is further enhanced, and the suction of the scroll unit 20 is achieved by reducing the pressure loss of the refrigerant and the supercharging effect of the refrigerant. The efficiency, i.e. the performance of the scroll compressor, is improved.

The above-described spiral groove 64 does not cause an increase in the diameter of the rotor 54 or an increase in the number of parts, thereby preventing an increase in the size of the scroll compressor and greatly contributing to the weight reduction.
The present invention is not limited to the above-described embodiment, and various modifications can be made.
For example, in the case of one embodiment, the notch 66 is formed on the outer periphery of each electromagnetic steel sheet 62 to obtain the spiral groove 64, but after forming a laminated body made of the electromagnetic steel sheet, the outer peripheral surface of this laminated body is formed. The spiral groove 64 may be processed.

A plurality of spiral grooves 64 may be provided in the rotor 54.
Furthermore, the scroll type fluid machine of the present invention can be used as a scroll expander in addition to the compressor.

It is sectional drawing which showed the scroll type fluid machine as a compressor. It is the perspective view which showed the rotor of FIG. It is the front view which showed the electromagnetic steel plate which comprises the rotor of FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Housing 20 Scroll unit 38 Armature 54 Rotor 62 Magnetic steel plate 64 Spiral groove (refrigerant path)
66 Notch Ga Air gap (refrigerant path)
Gb gap (refrigerant path)

Claims (4)

A housing;
An armature housed together with a scroll unit in the housing and driving the scroll unit;
A fluid path secured in the housing and guiding a working fluid through the armature to the scroll unit;
The scroll fluid machine according to claim 1, wherein the fluid path includes spiral grooves that are provided on an outer peripheral surface of the rotor of the armature and open at both end surfaces of the rotor.   2. The scroll type fluid machine according to claim 1, wherein the scroll unit is a compression unit for a refrigeration circuit, and the fluid path is a refrigerant path for returning the refrigerant to the compression unit.   3. The scroll type fluid machine according to claim 1, wherein the rotor is made of a laminated body of electromagnetic steel plates having notches on an outer periphery, and has the spiral groove in which the notches of individual electromagnetic steel plates are connected.   3. The scroll fluid machine according to claim 1, wherein the rotor is made of a laminate of electromagnetic steel plates and has the spiral groove formed on an outer peripheral surface of the laminate.

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