JP6808312B2 - Electric compressor - Google Patents

Description

The present invention relates to an electric compressor that drives a compression mechanism unit via a rotary drive shaft by an electric motor.

In electric compressors applied to refrigerators, air conditioners, and the like, magnet motors in which permanent magnets are embedded in rotors are used as electric motors. It is known that when the same output is obtained by using this magnet as a rare earth magnet and increasing the magnetic force, the axial thickness dimension of the rotor can be reduced, and the weight and size of the electric motor and thus the electric compressor can be reduced. However, when a rare earth magnet is used, the weight of the rotor itself becomes lighter and the inertial force during rotation becomes smaller, so that the angular velocity fluctuation of the motor rotor becomes larger due to the fluctuation of the gas compression torque during the compression stroke. This causes a decrease in the efficiency of the electric compressor and an increase in vibration and noise.

Therefore, in order to reduce the angular velocity fluctuation of the motor rotor, improve the performance of the electric compressor, and reduce vibration and noise, as shown in Patent Documents 1 and 2, at least one end surface or both end surfaces of the motor rotor. A mass body (weight member) as a rotary inertial body is provided in the motor, and the inertial force suppresses the angular velocity fluctuation of the motor rotor.

Japanese Unexamined Patent Publication No. 2005-248843 JP-A-2007-146736

However, at least one end of the rotary drive shaft coupled to the motor rotor is provided with a compression mechanism via a bearing member, and when the rotor is provided with a weight member, its weight and the compression mechanism and electric power are provided. A swing of a magnitude proportional to the distance between the motors may occur, which may adversely affect the balance of the rotating system. Further, depending on the shape and fixing structure of the weight member, for example, in order to use it as a balance weight for balancing the rotating system, a protruding portion may be provided on a part of the outer peripheral surface or the outer end surface, or a caulked portion of the rivet for fixing the weight member If the structure is such that the rivet is projected, the protruding portion agitates the lubricating oil and the refrigerant gas in the electric compressor, which may be a factor of promoting power loss and oil rise. Therefore, the shape and fixed structure of the weight member may be changed. It was necessary to devise it.

The present invention has been made in view of such circumstances, and the rotor is provided with a weight member as a rotating inertial body to reduce the angular velocity fluctuation of the rotor to improve the performance of the electric compressor, noise, and vibration. It is an object of the present invention to provide an electric compressor capable of suppressing the runout of the weight member and the oil rising due to the stirring of the lubricating oil and the refrigerant gas.

In order to solve the above-mentioned problems, the electric compressor of the present invention employs the following means.
That is, the electric compressor according to the present invention has an electric motor composed of a stator and a rotor, a rotation drive shaft coupled to the rotor of the electric motor, and rotation on at least one end side of the rotation drive shaft. It is configured to include a bearing member that supports the drive shaft, and is provided on a compression mechanism portion driven via the rotation drive shaft and at least on the end face or both end faces of the rotor of the electric motor on the compression mechanism portion side. The weight member provided with a weight member as a rotary inertial body and provided on the end surface of the rotor on the compression mechanism portion side is overhung on the outer periphery of the boss portion of the bearing member constituting the compression mechanism portion. , The outer end surface of which is a ring-shaped weight member having a flat surface.

According to the present invention, a weight member as a rotational inertia body provided at least on the end surface of the rotor on the compression mechanism side is provided by overhanging the outer periphery of the boss portion of the bearing member constituting the compression mechanism, and outside the weight member. Since the ring-shaped weight member has a flat end face, the weight member as a rotary inertial body increases the inertial force to reduce the angular velocity fluctuation of the motor rotor due to the fluctuation of the gas compression torque during the compression stroke. In addition to being able to improve the performance of the electric compressor and reduce noise and vibration, by installing the weight member as close to the compression mechanism as possible, it is possible to suppress the vibration caused by the weight member. At the same time, the lubricating oil in the electric compressor is agitated by the rotation of the weight member, and the oil rising due to the lubricating oil being wound up can be reduced. Therefore, it is possible to further improve the efficiency of the electric compressor, improve the performance, reduce the vibration, and reduce the noise. Further, by reducing the amount of oil rising, it is possible to improve the reliability of lubrication and the heat exchange performance on the refrigeration cycle side.

Further, in the electric compressor of the present invention, in the above electric compressor, the weight members provided on both end faces of the rotor are ring-shaped weight members having flat outer end faces. Features.

According to the present invention, since the weight members provided on both end faces of the rotor are ring-shaped weight members whose outer end faces are flat, the outer peripheral surface and outer end face of the rotating weight member are electrically driven. It is possible to suppress agitation due to contact with the lubricating oil or refrigerant gas in the compressor, and reduce power loss due to the agitation, hoisting of the lubricating oil, contact between the oil and the refrigerant gas, and oil rise due to promotion of mixing. .. Therefore, it is possible to further improve the efficiency of the electric compressor, improve the reliability of lubrication by reducing the oil rise, and improve the heat exchange performance on the refrigeration cycle side.

Further, in the electric compressor of the present invention, in any of the above-mentioned electric compressors, the weight member is attached to the rotor by rivets or bolts / nuts at a counterbore portion provided at a plurality of positions on the outer end surface thereof. It is characterized in that the caulked portion of the rivet or the head of the bolt / nut can be housed in the seating portion by being integrally connected to the rivet.

According to the present invention, the weight member is integrally connected to the rotor by a rivet or a bolt / nut at a counterbore portion provided at a plurality of positions on the outer end surface thereof, and the caulked portion of the rivet or the bolt / nut Since the head can be stored in the seat, the weight member is integrally connected to the rotor with rivets or bolts and nuts at the seat, and the crimped part or the head of the bolt and nut is seated. By storing it in the hollow portion, the crimped portion or the head of the bolt / nut can be prevented from protruding outward from the outer end surface of the weight member. Therefore, it is possible to prevent the lubricating oil and the refrigerant gas from being agitated by the crimped portion of the rivet or the head of the bolt / nut, and further reduce the oil rise.

Further, in the electric compressor of the present invention, in any of the above-mentioned electric compressors, the weight member has an asymmetric shape in which a hole is provided at a predetermined eccentric direction position, and is a rotary inertial body and a balance weight. It is characterized by being.

According to the present invention, the weight member has an asymmetric shape in which a hole is provided at a predetermined eccentric direction position, and is a rotating inertial body and a balance weight. Therefore, the weight member which is a rotating inertial body has a predetermined eccentricity direction. By providing a hole at the position and reducing the weight on the hole side, the weight member can function not only as a rotating inertial body but also as a balance weight for balancing the rotating system. Therefore, it is possible to have two functions as a rotary inertial body and a balance weight only by providing a hole portion without providing a protruding portion or the like on one weight member, and enjoy each effect and the above-mentioned effect. However, the configuration can be simplified and the cost can be reduced.

Further, in the electric compressor of the present invention, in any of the above-mentioned electric compressors, the weight member is a non-magnetic material on a part of the end face side of the rotor and a magnetic material on a part of the outer end face side thereof. It is characterized by being done.

According to the present invention, a part of the weight member on the end face side of the rotor is made of a non-magnetic material, and a part of the outer end face side of the weight member is made of a magnetic material. Therefore, magnetic flux leakage from the rotor end face is caused by the non-magnetic material part. A part of the weight member can be made of a low-cost material such as an iron-based material which is a magnetic material while preventing the weight member. That is, normally, as this kind of weight member, a non-magnetic material such as brass (brass) or stainless steel, which is a high specific gravity metal material, is used in order to prevent magnetic flux leakage, but a part of the end face side of the rotor is used. Is made of a non-magnetic material such as brass material, stainless steel material, high manganese steel, etc., and a part of the outer end face side is made of a magnetic material, so that a part of the weight member is inexpensive while preventing magnetic flux leakage from the rotor end face. It can be an iron-based material such as cast iron. Therefore, it is possible to satisfy the function as a weight member and at the same time reduce the cost.

Further, in the electric compressor of the present invention, in the above electric compressor, the non-magnetic material portion of the weight member has a thickness dimension t of at least 5% or more with respect to the axial thickness H of the rotor. It is characterized by being done.

According to the present invention, since the non-magnetic material portion of the weight member has a thickness dimension t of at least 5% or more with respect to the axial thickness H of the rotor, the non-magnetic material portion of the weight member is rotated. By setting the thickness dimension t to 5% or more of the axial thickness H of the child, it is possible to sufficiently prevent magnetic flux leakage while making a part of the outer end surface side a magnetic material such as inexpensive cast iron. Therefore, it is possible to satisfy the function as a weight member and at the same time reduce the cost.

Further, the electric compressor of the present invention is characterized in that, in any of the above-mentioned electric compressors, the weight of the weight member is at least 10% or more of the total weight of the rotor.

According to the present invention, the weight of the weight member is at least 10% or more of the total weight of the rotor. Therefore, the weight of the rotor and the weight of at least 10% of the total weight of the rotor are set. The total weight with the weight of the weight member secures the weight required to reduce the angular velocity fluctuation of the motor rotor due to the fluctuation of the gas compression torque, and obtains the required inertial force to obtain the angular velocity fluctuation of the rotor. It can be reduced. Therefore, it is possible to eliminate the decrease in efficiency, vibration, and noise due to the fluctuation of the angular velocity of the rotor, improve the performance of the electric compressor, and reduce the vibration and noise.

According to the present invention, by increasing the inertial force with the weight member as the rotary inertial body, the angular velocity fluctuation of the motor rotor due to the fluctuation of the gas compression torque during the compression stroke is reduced, the performance of the electric compressor is improved, and the noise. In addition to being able to reduce vibration, by installing the weight member as close to the compression mechanism as possible, it is possible to suppress the runout caused by the weight member, and the rotation of the weight member makes it electric. Since the lubricating oil in the compressor is agitated and the oil rise due to the lubricating oil being wound up can be reduced, the efficiency of the electric compressor can be further improved, and the performance, vibration and noise can be reduced. Can be done. Further, by reducing the amount of oil rising, it is possible to improve the reliability of lubrication and the heat exchange performance on the refrigeration cycle side.

It is a vertical sectional view of the electric compressor which concerns on one Embodiment of this invention. It is a top view which looked at the rotor of the electric motor built into the electric compressor from the end face side.

An embodiment of the present invention will be described below with reference to FIGS. 1 and 2.
FIG. 1 shows a vertical cross-sectional view of an electric compressor according to an embodiment of the present invention, and FIG. 2 shows a plan view of the rotor of the electric motor as viewed from the end face side.
The electric compressor 1 of the present embodiment is a two-cylinder rotary type electric compressor 1 in which an electric motor 3 and a two-cylinder rotary type compression mechanism unit 4 are built in a sealed housing 2. It goes without saying that the invention is not limited to such a two-cylinder rotary type electric compressor 1.

An electric motor 3 including a stator 5 and a rotor 6 is fixedly installed in an upper portion of the sealed housing 2. The stator 5 is formed by laminating a large number of annular magnetic steel plates obtained by punching and forming a plurality of teeth portions on the inner peripheral side, and centrally winding a stator winding 8 such as an aluminum winding around the teeth portions via an insulating bobbin 7. On the other hand, the rotor 6 is made by laminating a large number of annular magnetic steel plates obtained by punching out a plurality of magnet insertion holes, and in the magnet insertion holes, a ferrite magnet, a rare earth neodymium magnet, a disprosium magnet, etc. By inserting the permanent magnetic force (not shown) of the above, the magnet is integrally connected in a cylindrical shape by a rivet, a bolt, a nut, or the like, and is attached to the inner peripheral portion of the stator 5 via an air gap.

The electric motor 3 is fixedly installed in the closed housing 2 by the stator 5 being shrink-fitted in the closed housing 2, and a two-cylinder rotary type compression mechanism portion 4 is fixedly installed in a lower portion thereof. ing. A rotation drive shaft 9 is integrally coupled to the rotor 6 of the electric motor 3, and the compression mechanism unit 4 is driven by connecting the compression mechanism unit 4 to the other end portion of the rotation drive shaft 9. It is said that it is configured. In the lower portion of the rotation drive shaft 9, eccentric shaft portions 9A and 9B are arranged so as to face each other with a phase shift of 180 degrees at two locations at predetermined intervals above and below.

The compression mechanism unit 4 includes a pair of upper and lower upper bearing members 10 and a lower bearing member 11, and a pair of upper and lower cylinder bodies 13A and 13B provided with a separator plate 12 sandwiched between the upper and lower bearing members 10 and the lower bearing member 11. The cylinder chambers 14A and 14B formed in the cylinder bodies 13A and 13B and whose upper and lower parts are sealed by the upper bearing member 10, the lower bearing member 11 and the separator plate 12, and the eccentric shaft of the rotation drive shaft 9 in the cylinder chambers 14A and 14B. Rotors 15A and 15B that are rotatably fitted to the portions 9A and 9B and rotate on the inner peripheral surfaces of the cylinder chambers 14A and 14B, and slidable in the radial grooves provided in the cylinder bodies 13A and 13B. The cylinder chambers 14A and 14B are fitted with a vane that divides the inside of the cylinder chambers 14A and 14B into a suction side and a discharge side, and a vane holding spring (both not shown) and the like.

The upper bearing member 10 and the lower bearing member 11 rotatably support the rotary drive shaft 9 with the upper bearing member 10 as the main bearing and the lower bearing member 11 as the sub bearing, and the cylinder body 13A, on the lower surface and the upper surface thereof. One end surfaces of the cylinder chambers 14A and 14B formed in 13B are sealed. The two-cylinder rotary type compression mechanism unit 4 is a well-known and well-known one.

As shown in FIG. 1, the compression mechanism unit 4 has cylinder bodies 13A and 13B, a separator plate 12, an upper bearing member 10 and a lower bearing member 11 having cylinder bodies 13A and 13B on both sides of the separator plate 12 as shown in FIG. Further, the upper bearing member 10 and the lower bearing member 11 are stacked on the upper and lower end surfaces of the cylinder bodies 13A and 13B so as to be integrally connected by bolts or the like, and the upper bearing member 10 is welded (plugged) to the sealed housing 2 at a plurality of places. By welding), it is fixedly installed in the sealed housing 2. Instead of the upper bearing member 10, any of the cylinder bodies 13A and 13B may be fixedly installed in the closed housing 2.

Low-pressure refrigerant gas that has circulated in the refrigeration cycle is sucked into the pair of upper and lower cylinder chambers 14A and 14B of the compression mechanism unit 4 via an accumulator 19 that is integrally assembled and installed on the outer periphery of the sealed housing 2 by a bracket 18. The air is sucked through the suction ports 16A and 16B provided in the pipes 20A and 20B and the cylinder bodies 13A and 13B. Further, the low-pressure refrigerant gas sucked into the cylinder chambers 14A and 14B is rotated by the electric motor 3 in the cylinder chambers 14A and 14B via the eccentric shaft portions 9A and 9B of the rotary drive shaft 9. By doing so, the gas is compressed to a predetermined pressure and discharged into the discharge chambers 17A and 17B via a discharge valve (not shown).

The high-pressure refrigerant gas discharged into the discharge chambers 17A and 17B is discharged from the discharge chambers 17A and 17B into the closed housing 2 and formed between the outer peripheral surface of the stator 5 and the inner peripheral surface of the closed housing 2. It is guided into the upper space 22 of the electric motor 3 through the refrigerant flow path 21 and the like, and is circulated from there to the refrigeration cycle side via the discharge pipe 23. The bottom portion of the sealed housing 2 is an oil sump, and is filled with a required amount of lubricating oil in order to lubricate the sliding portion of the compression mechanism portion 4.

The electric motor 3 of the electric compressor 1 configured as described above has a balance weight function for balancing the rotational system on at least the lower end surface or the upper and lower end surfaces of the cylindrical rotor 6 on the compression mechanism portion 4 side. A weight member 25 having a function as a rotary inertial body for reducing the angular velocity fluctuation of the rotor 6 due to the fluctuation of the gas compression torque during the compression stroke is provided. In the present embodiment, the weight members 25 are provided on the upper and lower end surfaces of the rotor 6, but the weight members 25 may be provided only on the lower end surfaces on the compression mechanism 4 side.

Each weight member 25 has a circular shape with an outer circumference substantially the same as the outer diameter of the rotor 6, and is a ring-shaped mass body having both end surfaces flat. Further, the weight member 25 provided on the lower end surface of the rotor 6 is installed by inserting the upper end portion of the boss portion 10A of the upper bearing member 10 into the inner peripheral portion of the ring shape and overhanging the outer periphery of the boss portion 10A. The electric motor 3 and the compression mechanism unit 4 are installed close to each other so that the distance between them can be reduced as much as possible.

As shown in FIG. 2, on the outer end surface side of the weight member 25, seating portions 26 having predetermined depths are provided at four locations at equal intervals on the circumference. When the weight member 25 is integrally fixed and installed on both end faces of the rotor 6 via rivets 27 or bolts / nuts (not shown), the seating portion 26 is obtained by caulking the rivets 27 or heads of bolts / nuts. This is to prevent the portion from protruding outward from the flat outer end surface.

Further, the weight member 25 has a weight of at least 10% of the total weight of the rotor 6 in order to make the weight member 25 function as a rotary inertial body for reducing the angular velocity fluctuation of the rotor 6. To reduce the angular velocity fluctuation of the rotor 6 due to the fluctuation of the gas compression torque by the total weight of the weight of the child 6 and the weight of the weight member 25 having a weight exceeding at least 10% of the total weight of the rotor 6. By securing the required weight and obtaining the required inertial force, it is possible to reduce the angular velocity fluctuation of the rotor 6.

Further, the weight member 25 has two punched hole portions 28 at eccentric positions in a direction 180 degrees facing the eccentric shaft portion 9A of the rotation drive shaft 9 with respect to the weight member 25 provided on the lower end surface side of the rotor 6. On the other hand, the weight member 25 provided on the upper end surface side of the rotor 6 is provided with two punched holes 28 at eccentric positions in the same direction as the eccentric shaft portion 9A of the rotary drive shaft 9. The member 25 has an asymmetrical shape, and the hole 28 side is made lighter so that the weight member 25 also has a function as a balance weight for balancing the rotation system.

Further, the weight member 25 is made of two layers of different metal materials in the thickness direction. That is, a part of the end face side of the rotor 6 in contact with both end faces is a non-magnetic material 25A, and a part of the outer end face side is a magnetic body 25B. As the non-magnetic material 25A, brass material (brass), stainless steel material, high manganese steel, etc., which are high specific gravity metal materials, can be used in order to prevent magnetic flux leakage from the end face of the rotor 6, and the magnetic material 25B As an example, an inexpensive iron-based material such as cast iron can be used. As a result, the weight member 25 that can prevent magnetic flux leakage and secure the required weight while reducing the amount of brass material (brass), stainless steel material, high manganese steel, etc., which is a relatively expensive non-magnetic material 25A, as much as possible. Consists of.

In this case, the thickness t of the non-magnetic material 25A that prevents magnetic flux leakage is at least about 5% or more with respect to the axial thickness dimension H of the rotor 6 when the high specific gravity metal material is used. Dimension t. Incidentally, the axial thickness dimension H of the rotor 6 of this type of electric motor 3 is about 80 to 100 mm, and the thickness t of the non-magnetic body 25A is about 4 to 5 mm.

According to the present embodiment, the following functions and effects are obtained by the configuration described above.
In the above-mentioned electric compressor 1, the rotor 6 is rotationally driven by applying a current of a required frequency to the stator winding 8 of the electric motor 3 via an inverter, and the rotor 6 is rotationally driven and coupled to the rotor 6. The rotors 15A and 15B of the 2-cylinder rotary compression mechanism 4 are rotated via the shaft 9. As a result, the low-pressure refrigerant gas sucked into the cylinder chambers 14A and 14B via the suction pipes 20A and 20B and the suction ports 16A and 16B is compressed and discharged into the closed housing 2 via the discharge chambers 17A and 17B. This high-pressure refrigerant gas is guided to the upper space 22 of the electric motor 3 via the refrigerant flow path 21 and the like, and is circulated from there to the refrigeration cycle via the discharge pipe 23.

During this period, the unbalanced moment of the rotating system generated by the rotation of the rotary drive shaft 9 is caused by the weight members 25 provided on both end faces of the rotor 6 of the electric motor 3 functioning as counter weights, resulting in a static unbalance amount or movement. By taking the unbalance amount, the unbalance amount of the rotating system can be reduced, and the vibration and noise caused by the unbalance amount can be reduced. Therefore, it is possible to balance the rotating system in the electric compressor 1 and reduce the vibration and noise of the electric compressor 1.

On the other hand, the weight of the rotor itself becomes lighter due to the weight reduction and miniaturization of the rotor 6, and the inertial force during rotation becomes smaller. Therefore, the angular velocity of the rotor fluctuates due to the fluctuation of the gas compression torque during the compression stroke. There is a tendency for the size to increase, which causes a decrease in efficiency of the electric compressor and an increase in vibration and noise. However, a weight member 25 that functions as a rotational inertia body is provided on at least one end surface or both end surfaces of the rotor 6. As a result, the inertial force can suppress the fluctuation of the angular velocity of the rotor 6, and can suppress the decrease in efficiency and the increase in vibration and noise. As a result, the efficiency of the electric compressor 1 can be improved, the performance can be improved, the vibration can be reduced, and the noise can be reduced.

In particular, a weight member 25 as a rotational inertia body provided at least on the end surface of the rotor 6 on the compression mechanism portion 4 side is provided by overhanging the outer periphery of the boss portion 10A of the upper bearing member 10 constituting the compression mechanism portion 4. A ring-shaped weight member 25 having a flat outer end surface thereof is used. Therefore, by increasing the inertial force of the weight member 25 as the rotary inertial body, the angular velocity fluctuation of the rotor 6 due to the fluctuation of the gas compression torque during the compression stroke is reduced, and the performance of the electric compressor 1 is improved and the noise is improved. In addition to being able to reduce vibration, by installing the weight member 25 as close to the compression mechanism unit 4 side as possible, it is possible to suppress the swing of the weight member 25 and the weight member 25. The lubricating oil in the electric compressor 1 is agitated by the rotation of the compressor 1, and the oil rise due to the lubricating oil being wound up can be reduced.

Therefore, the efficiency of the electric compressor 1 can be further improved, the performance can be improved, the vibration can be reduced, and the noise can be reduced. At the same time, the reliability of lubrication can be improved by reducing the amount of oil rising, and the refrigeration cycle side. The heat exchange performance can be improved.

Further, in the present embodiment, since the weight members 25 are provided on both end surfaces of the rotor 6 and the outer end surfaces of the respective weight members 25 are flat ring-shaped weight members 25, they rotate. Stirring caused by contact of the outer peripheral surface and outer end surface of the weight member 25 with the lubricating oil and the refrigerant gas in the electric compressor 1 is suppressed, power loss due to the stirring, hoisting of the lubricating oil, and contact between the oil and the refrigerant gas. , It is possible to reduce oil rise due to promotion of mixing. As a result, it is possible to further improve the efficiency of the electric compressor 1, improve the reliability of lubrication by reducing the oil rise, and improve the heat exchange performance on the refrigeration cycle side.

Further, the weight member 25 is integrally connected to the rotor 6 by a rivet 27 or a bolt / nut at a counterbore portion 26 provided at a plurality of positions on the outer end surface thereof, and the caulked portion or the bolt of the rivet 27 is formed. The head of the nut is configured to be able to be stored in the seat 26. Therefore, the weight member 25 is integrally connected to the rotor 6 by the rivet 27 or the bolt / nut at the seating portion 26, and the crimped portion or the head of the bolt / nut is housed in the seating portion 26. Therefore, the crimped portion or the head of the bolt / nut can be prevented from protruding outward from the outer end surface of the weight member 25. Therefore, it is possible to prevent the lubricating oil and the refrigerant gas from being agitated by the crimped portion of the rivet 27 or the heads of the bolts and nuts, and further reduce the oil rise.

Further, in the present embodiment, the weight member 25 has an asymmetric shape in which a hole 28 is provided at a predetermined position in the eccentric direction, and the balance weight is also used for the rotary inertial body. Therefore, by providing the hole 28 at a predetermined position in the eccentric direction of the weight member 25 which is a rotating inertial body and reducing the weight on the hole 28 side, the weight member 25 is not only a rotating inertial body but also a rotating system. It can also function as a balance weight that balances. As a result, it is possible to have two functions as a rotary inertial body and a balance weight only by providing a hole 28 without providing a protruding portion or the like on one weight member 25. While enjoying the effect, the configuration can be simplified and the cost can be reduced.

Further, in the weight member 25, a part of the rotor 6 on the end face side is a non-magnetic body 25A, and a part of the outer end face side thereof is a magnetic body 25B. As a result, a part of the weight member 25 can be made of a low-cost material such as an iron-based material which is a magnetic material 25B while preventing magnetic flux leakage from the end face of the rotor 6 by a non-magnetic material 25A portion.

That is, normally, as the weight member 25 of this type, a non-magnetic material such as brass (brass) or stainless steel, which is a high specific gravity metal material, is used in order to prevent magnetic flux leakage, but the end face side of the rotor 6 is usually used. By using a non-magnetic material 25A made of brass material, stainless steel material, high manganese steel, etc., and a part of the outer end surface side made of magnetic material 25B, while preventing magnetic flux leakage from the end surface of the rotor 6, Since a part of the weight member 25 can be made of an inexpensive iron-based material such as cast iron, the function as the weight member 25 can be satisfied and the cost can be reduced at the same time.

At this time, the non-magnetic material portion 25A of the weight member 25 has a thickness dimension t that exceeds at least 5% with respect to the axial thickness H of the rotor 6. In this way, by setting the non-magnetic material portion 25A of the weight member 25 to have a thickness dimension t of 5% or more of the axial thickness H of the rotor 6, a part of the outer end surface side is magnetic of inexpensive cast iron or the like. It is possible to sufficiently prevent magnetic flux leakage while using the body 25B. Therefore, it is possible to satisfy the function as the weight member 25 and at the same time reduce the cost.

Further, in the present embodiment, the weight of the weight member 25 is set to be at least 10% of the total weight of the rotor 6. Therefore, the total weight of the rotor 6 and the weight of the weight member 25, which is at least 10% of the total weight of the rotor 6, causes the angular velocity fluctuation of the rotor 6 to be caused by the fluctuation of the gas compression torque. By securing the weight required for reduction and obtaining the required inertial force, it is possible to reduce the angular velocity fluctuation of the rotor 6. Therefore, it is possible to eliminate the decrease in efficiency, vibration, and noise due to the fluctuation of the angular velocity of the rotor 6, improve the performance of the electric compressor 1, and reduce the vibration and noise.

The present invention is not limited to the invention according to the above embodiment, and can be appropriately modified without departing from the gist thereof. For example, in the above embodiment, an example applied to the two-cylinder rotary type electric compressor 1 has been described, but the single-cylinder rotary type electric compressor, the scroll type electric compressor, and the electric motor 3 are located below the sealed housing 2. Various electric compressors in which the compression mechanism 4 is installed in the upper part of the sealed housing 2, and two sets of compression mechanisms 4 are installed above and below the electric motor 3 in between. Of course, it can be applied to compressors and the like as well.

Further, the electric compressor 1 according to the present invention can be applied not only to a compressor for a refrigeration cycle using a refrigerant such as R407C, R410A, R32, R1234yf, but also a refrigerating machine oil having applicability to those refrigerants. It goes without saying that the same applies to compressors used as lubricating oil.

1 Electric compressor 3 Electric motor 4 Compression mechanism 5 Stator 6 Rotor 9 Rotating drive shaft 10 Upper bearing member 10A Boss 11 Lower bearing member 25 Weight member 25A Non-magnetic material 25B Magnetic material 26 Seating part 27 Rivets 28 holes Department

Claims (6)

An electric motor consisting of a stator and a rotor,
A rotary drive shaft coupled to the rotor of the electric motor,
A compression mechanism portion that includes a bearing member that supports the rotary drive shaft on at least one end side of the rotary drive shaft and is driven via the rotary drive shaft.
A weight member as a rotational inertia body provided at least on the end face or both end faces of the rotor of the electric motor on the compression mechanism side side is provided.
The weight member provided on the end surface of the rotor on the compression mechanism portion side is overhanged on the outer periphery of the boss portion of the bearing member constituting the compression mechanism portion, and the outer end surface thereof has a flat ring shape. It is considered as a weight member of
The weight member has an annular magnetic material and an annular non-magnetic material arranged in the thickness direction, the end face side of the rotor is the non-magnetic material, and the outer end surface side thereof is the magnetic material. An electric compressor characterized by being. The electric compressor according to claim 1, wherein the weight members provided on both end faces of the rotor are ring-shaped weight members whose outer end faces are flat. The weight member is integrally connected to the rotor by a rivet or a bolt / nut at a counterbore portion provided at a plurality of positions on the outer end surface thereof, and the caulked portion of the rivet or the head of the bolt / nut. The electric compressor according to claim 1 or 2, wherein is capable of being housed in the seating portion. The electric compressor according to any one of claims 1 to 3, wherein the weight member has an asymmetric shape in which a hole is provided at a predetermined position in an eccentric direction, and is a rotary inertial body and a balance weight. .. According to any one of claims 1 to 4, the non-magnetic material portion of the weight member has a thickness dimension t of at least 5% or more with respect to the axial thickness H of the rotor. The electric compressor described. The electric compressor according to any one of claims 1 to 5, wherein the weight of the weight member is at least 10% or more of the total weight of the rotor.

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