JPH0886292A - Closed type motor-driven compressor - Google Patents

Abstract

PURPOSE: To improve reliability and the coefficient of performance through suppression of scattering and outflow of lubrication oil and to block outflow of oil from the bottom of a container to an electric motor part by moving recovery lubrication oil to the outer peripheral wall part of an oil recovery container. CONSTITUTION: Lubricating oil recovered to an oil recovery container 28 after lubrication and cooling of a bearing part is dragged and moved through rotation of an eccentric weight 29 through rotation of a crankshaft 12 and simultaneously moved toward the outer peripheral wall part of the oil recovery container 28 by a centrifugal force. However, when lubrication oil is reversed to the oil recovery container 28, the lubrication oil is moved to the outer peripheral wall part of the oil recovery container 28 by means of a slope 33 inclined upward based on the axial direction of the crankshaft 12 formed at the end face part of the eccentric weight 29.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a compressor used for a cooling device such as an air conditioner or a refrigerator, and a hermetic electric compressor such as a scroll compressor or a rotary compressor.

[0002]

2. Description of the Related Art The structure of a conventional hermetically-operated compressor used for a cooling device such as an air conditioner and a refrigerator will be described with reference to FIG.

In FIG. 9, a compression mechanism portion 101 includes a fixed scroll 103 having fixed spiral blades 102, an orbiting scroll 106 in which orbiting spiral blades 104 are formed on an orbiting end plate 105, and Oldham which prevents rotation of the orbiting scroll 106. The fixed scroll 103 is fixed to the sealed container 109 together with the bearing member 108. In the orbiting end plate 105 of the orbiting scroll 106, an orbiting scroll shaft 110 is provided on the surface opposite to the surface on which the orbiting spiral blades 104 are provided.
8 and an auxiliary bearing member 111 are fitted into an eccentric hole 113 formed at the upper end of a crankshaft 112 rotatably supported. Between the bearing member 108 and the sub-bearing member 111, a stator 114 fixed to the closed container 109 is provided.
And a rotor 115 fixed to the crankshaft 112 and rotating together with the crankshaft 112.
Is provided.

The inside of the closed container 109 has a compression mechanism 10
Discharge port 11 for discharging the high-pressure refrigerant gas compressed by 1.
7, the discharge side chamber 118, and the electric motor unit 11
6 is installed in the electric motor side chamber 119 and is partitioned by the compression mechanism section 101. The discharge port side chamber 118 and the electric motor side chamber 119 are connected to the communication port 1 provided in the compression mechanism section 101.
It is communicated by 20.

Due to the above configuration,
The low-pressure refrigerant gas sucked through the suction pipe 129 is compressed by the compression mechanism portion 101 to become high-pressure refrigerant gas, and the discharge port side chamber 1
The high-pressure refrigerant gas discharged to 18 passes through the communication port 120 and flows into the electric motor side chamber 119, and its main flow is downward as shown by the arrow. Stator 114 of electric motor unit 116
The outer periphery of the closed container 10 is substantially coaxial with the communication port 120.
9 is provided with a notch 121 in the vertical direction, the main flow of the high-pressure refrigerant gas in the downward direction is the notch 121.
To reach the lower portion of the hermetically sealed container 109, and then passes through the lower portion of the stator 114 to pass through the stator 114 of the electric motor unit 116.
Through the discharge gas passage 122 provided in the lower part of the compression mechanism 101, and finally discharged from the discharge pipe 123 to the outside of the closed container 109.

On the other hand, a lubricating oil pump 124 is installed at the lower end of the crankshaft 112, and the lubricating oil pump 124 is
With the rotation of the crankshaft 112, the lubricating oil accumulated in the lubricating oil reservoir 125 provided at the bottom of the closed container 109 is
It pumps up to the compression mechanism part 101 via the communicating path 126 formed in the central part of the crankshaft 112. Most of the lubricating oil that has passed through the communication passage 126 lubricates the orbiting scroll shaft 110 to lubricate the main bearing 127, and then is discharged from the upper portion of the oil recovery container 128 and recovered in the oil recovery container 128.

The lubricating oil collected and stored in the oil recovery container 128 is agitated by the rotation of an eccentric weight 129 which is integrally attached to the crankshaft 112 for balancing, and a centrifugal force is applied to the lubricating oil. By the action of this centrifugal force, the oil is pushed out into the chamber 130 provided in the oil recovery container 128 through the communication hole 131. Then, the lubricating oil is further pushed up into the chamber 130, and the bearing member 108 of the compression mechanism unit 101.
After being pushed through the oil drain passage 132 provided in the above, the oil is discharged to a position substantially in phase with the notch 121 provided on the outer periphery of the stator 114 of the electric motor unit 116.

[0008]

In the conventional hermetic electric compressor, the bottom of the oil recovery container 128 and the crankshaft 1 are used.
There is a gap 133 between the eccentric weight 12 and
Since the centrifugal force by 9 gradually weakens in the portion where the eccentric weight 129 does not exist, the lubricating oil easily flows back into the oil recovery container 128, and the end surface of the eccentric weight 129 is formed by a surface perpendicular to the axial direction. Therefore, when a large amount of lubricating oil is pumped from the lubricating oil pump 124, the lubricating oil collects on the end surface of the eccentric weight 129 and the oil recovery container 128 and the crankshaft 112.
There is a case where the lubricating oil that has flowed out from the gap 133 to the lower portion is stirred by the rotor 115 of the electric motor unit 116 and scattered as a large amount of oil droplets in the electric motor side chamber 119.

Further, the discharge from the compression mechanism section 101,
Since the high-pressure refrigerant gas introduced into the electric motor side chamber 119 through the communication port 120 comes into contact with and collects a large amount of scattered oil droplets, the high-pressure refrigerant gas mixed with a large amount of lubricating oil is
Loss of pipe pressure during the refrigeration cycle is caused by the lubricating oil that is discharged from the discharge pipe 123 through the discharge gas passage 122 to the outside of the closed container 109 and is mixed in the discharged high pressure refrigerant gas. However, there is a problem in that the heat exchange efficiency increases in a heat exchanger such as a condenser and an evaporator, and the reliability and the coefficient of performance of the compressor decrease.

An object of the present invention is to provide a hermetic electric compressor which suppresses the scattering and outflow of lubricating oil and has a high reliability and a high coefficient of performance.

[0011]

In order to achieve the above object, in a hermetic electric compressor of the present invention, a compression mechanism portion and an electric motor for driving the compression mechanism portion via a crankshaft in a hermetic container. And a lower portion of the compression mechanism section, a lubricating oil recovery section having an eccentric weight attached to the crankshaft and an oil recovery container surrounding the eccentric weight is formed, and the lubricating oil recovery section is formed. In addition, a moving means for moving the recovered lubricating oil to the outer peripheral wall of the oil recovery container is provided.

As a moving means for moving the recovered lubricating oil to the outer peripheral wall of the oil recovery container, an inclined surface inclined upward with respect to the axial direction of the crankshaft may be provided at the end surface of the eccentric weight. , The end face of the eccentric weight is provided with an inclined surface that is inclined with respect to the radial direction of the crankshaft, or the eccentric weight has an outer peripheral portion that is thicker than the central portion, and along the lower end surface of the eccentric weight. A parallel bottom is provided on the oil recovery container, a step is provided on the outer peripheral wall of the oil recovery container, or a gap that is smaller than the gap between the outer periphery of the oil recovery container and the outer end face of the eccentric weight. Can be formed between the bottom of the oil recovery container and the lower end surface of the eccentric weight.

[0013]

In the hermetic electric compressor configured as described above, the lubricating oil collected in the oil recovery container by lubricating and cooling the bearing part is rotated by the eccentric weight due to the rotation of the crankshaft. At the same time as it is dragged and moved, it is moved toward the outer peripheral wall of the oil recovery container by the centrifugal force and is returned to the lubricating oil sump. On the other hand, in the part where the eccentric weight does not exist, the rotational speed of the lubricating oil gradually weakens and the centrifugal force decreases, so the lubricating oil that has moved to the outer peripheral wall of the oil recovery container flows backward toward the inside of the oil recovery container. However, by the moving means that moves the recovered lubricating oil to the outer peripheral wall of the oil recovery container,
Since the lubricating oil is forcibly moved to the outer peripheral wall of the oil recovery container, it does not flow out from the bottom of the oil recovery container to the electric motor section.

The lubricating oil flowing back into the oil recovery container is inclined on the end face of the eccentric weight and is inclined upward with respect to the axial direction of the crankshaft, or inclined with respect to the radial direction of the crankshaft. It is possible to move it toward the outer peripheral wall surface of the oil recovery container by the inclined surface.

Further, when the eccentric weight is thicker on the outer peripheral portion than on the central portion and the bottom portion having a shape along the lower end surface of the eccentric weight is provided in the oil recovery container, the oil recovery container communicating with the electric motor section is provided. The clearance between the crankshaft and the crankshaft is at a high position, and it becomes difficult for the lubricating oil to flow out, and it is easy for the lubricating oil to collect on the outer peripheral wall surface.

Further, the lubricating oil collects on the stepped portion formed on the outer peripheral wall of the oil recovery container, and it is difficult for the lubricating oil to flow out to the electric motor section. Further, the gap between the outer peripheral part of the oil recovery container and the outer end face of the eccentric weight is provided. If a smaller gap is formed between the bottom of the oil recovery container and the lower end surface of the eccentric weight, centrifugal force easily acts on the lubricating oil existing at the bottom of the oil recovery container, causing the lubricating oil to flow out. It will be difficult.

[0017]

DESCRIPTION OF THE PREFERRED EMBODIMENTS A hermetic electric compressor of the present invention will be described with reference to FIGS. 1 to 8 by taking a hermetic electric scroll compressor as an embodiment.

In FIG. 1, the compression mechanism section 1 includes a fixed scroll 3 having fixed spiral vanes 2, a swirl scroll 6 having swirl spiral vanes 4 formed on a swirl end plate 5, and Oldham which prevents rotation of the swirl scroll 6. The fixed scroll 3 is fixed to the hermetically sealed container 9 together with the bearing member 8. In the orbiting end plate 5 of the orbiting scroll 6, an orbiting scroll shaft 10 is provided on the surface opposite to the surface on which the orbiting spiral blades 4 are provided,
The orbiting scroll shaft 10 is fitted in an eccentric hole 13 formed at the upper end of a crank shaft 12 which is rotatably supported by a bearing member 8 and an auxiliary bearing member 11. Between the bearing member 8 and the sub-bearing member 11, there is arranged an electric motor unit 16 which is a stator 14 fixed to the closed container 9 and a rotor 15 fixed to the crankshaft 12 and rotating with the crankshaft 12. It is set up.

Inside the closed container 9, a discharge port side chamber 18 in which a discharge port 17 for discharging the high-pressure refrigerant gas compressed by the compression mechanism section 1 is provided, and an electric motor side chamber 19 in which the electric motor section 16 is installed. Further, the discharge side chamber 18 and the electric motor side chamber 19 are partitioned by the compression mechanism unit 1 and are communicated with each other by a communication port 20 provided in the compression mechanism unit 1.

Due to the above configuration,
The low pressure refrigerant gas sucked through the suction pipe 29 is compressed by the compression mechanism unit 1.
Is compressed into high pressure refrigerant gas, and the high pressure refrigerant gas discharged to the discharge side chamber 18 passes through the communication port 20 and flows into the electric motor side chamber 19, the main flow of which is downward as shown by an arrow (see FIG. 1). Has become. On the outer periphery of the stator 14 of the electric motor section 16, a notch 21 that is substantially coaxial with the communication port 20 and is provided in the up-down direction with respect to the closed container 9 is provided. It passes through the portion 21 to reach the lower portion of the closed container 9, then passes through the lower portion of the stator 14, passes through the gap between the stator 14 and the rotor 15 of the electric motor portion 16, and is provided at the lower portion of the compression mechanism portion 1. After passing through the discharge gas passage 22 thus formed, it is finally discharged from the discharge pipe 23 to the outside of the closed container 9.

On the other hand, a lubricating oil pump 24 is installed at the lower end of the crankshaft 12, and the lubricating oil pump 24 is stored in a lubricating oil sump 25 provided at the bottom of the closed container 9 as the crankshaft 12 rotates. The lubricating oil is
It is pumped up to the compression mechanism part 1 through the communication passage 26 formed in the central part of the. Most of the lubricating oil that has passed through the communication passage 26 lubricates the orbiting scroll shaft 10 to lubricate the main bearing 27, and then is discharged from the upper portion of the oil recovery container 28 to be discharged from the oil recovery container 2
Recovered within 8.

The lubricating oil collected and stored in the oil recovery container 28 is integrally attached to the crankshaft 12 in order to balance the rotation of the crankshaft 12, and the oil recovery container 2
Eccentric weight 2 having a semicircular cross section and surrounded by 8
9 (see FIG. 3) is agitated by rotation of 9 (see FIG. 3), and by the action of this centrifugal force, it is extruded into the chamber 30 provided in the oil recovery container 28 through the communication hole 31. Then,
The lubricating oil is further pushed up in the chamber 30 and pushed through the oil drain passage 32 provided in the bearing member 8 of the compression mechanism unit 1, and then the notch formed in the outer periphery of the stator 14 of the electric motor unit 16. 21 is discharged to a position almost in phase with the lubricating oil sump 2
Reflux to 5. Reference numeral 33 denotes an inclined surface formed on the end surface portion of the eccentric weight 29, which is inclined upward with respect to the axial direction of the crankshaft 12.

The movement of the lubricating oil in the oil recovery container 28 will be described with reference to FIG. 2 showing a schematic view of the oil recovery container 28 and FIG. 3 showing a sectional view taken along the line AA in FIG.
Point P indicates the position of the lubricating oil during operation.

The lubricating oil M existing between the eccentric weight 29 and the oil recovery container 28 is dragged by the rotation of the eccentric weight 29 due to the rotation of the crankshaft 12, and at the same time, the centrifugal force thereof causes the oil recovery container to move. It moves toward the outer peripheral wall of 28 and is introduced into the chamber 30 of the oil recovery container 28 through the communication hole 31. On the other hand, in the portion 34 where the eccentric weight 29 does not exist,
Since the rotational speed of the lubricating oil M gradually decreases and the centrifugal force decreases, the lubricating oil M that has moved to the outer peripheral wall of the oil recovery container 28
Flows back toward the inside of the oil recovery container 28. When the backflowing lubricating oil M hits the end surface portion of the eccentric weight 29, the inclined surface 33 prevents the lubricating oil M from flowing out of the gap 35 between the oil recovery container 28 and the crankshaft 12 to the electric motor portion 16 and the crankshaft. By the rotation of 12, the inclined surface 33
The eccentric weight 29 again moves to the outer peripheral wall portion of the oil recovery container 28 because the eccentric weight 29 again applies a centrifugal force.

Therefore, the scattering of the lubricating oil M by the rotor 15 is prevented, the amount of the lubricating oil M mixed in the discharged high-pressure refrigerant gas is reduced, and the lubricating oil mixed in the discharged high-pressure refrigerant gas is the cause. There is no loss of piping pressure in the refrigeration cycle, no decrease in heat exchange efficiency in heat exchangers such as condensers and evaporators, and no decrease in compressor reliability or coefficient of performance.

Further, as shown in FIGS. 4 and 5, the eccentric weight 29 may have a columnar shape having a fan-shaped cross section, and an inclined surface 36 inclined to the radial direction of the crankshaft 12 may be provided on the end surface portion thereof. . In this case, the eccentric weight 2
The lubricating oil M that has abutted against the end surface portion of 9 is pushed out to the outside, that is, in the direction of the outer circumference of the oil recovery container 28 due to the existence of the inclined surface 36, so that it does not flow out from the gap 35 to the electric motor portion 16.

Further, as shown in FIG. 6, the eccentric weight 29 has a columnar shape with a semicircular cross section, and has an inclined surface on the lower end surface so that the thickness gradually increases from the central portion on the crankshaft 12 side toward the outer peripheral portion. 37 is formed, and the bottom of the oil recovery container 28 is a conical bottom surface 38 along the inclined surface 37, the oil recovery container 28
Since the shape of the bottom portion of the oil is a medium-high tapered shape, the lubricating oil M collected at the bottom is smoothly collected by the centrifugal force in the oil recovery container 28.
Can be moved to the outer periphery of the gap 35, and the gap 35 is located at a high position so that the lubricating oil M does not easily flow out from the gap 35. The example in which the bottom of the oil recovery container 28 has a conical shape has been described, but the same effect can be obtained even if the lower end surface of the eccentric weight 29 is stepped to increase the wall thickness.

Further, as shown in FIG. 7, the oil recovery container 28
Of the eccentric weight 29, a relatively large gap 41 is formed between the eccentric weight 29 and the inner wall of the oil recovery container 28, and a small gap 42 is formed at the bottom. When formed, the lubricating oil M flowing from the upper portion of the oil recovery container 28 is temporarily stored in the step portion 40, and the lubricating oil existing in the lower gap portion 42 is centrifugally generated by the eccentric weight 29 to cause the step portion. Pushed up to 40. Therefore, the lubricating oil flowing out from the gap 35 to the electric motor section 16 disappears.

Further, as shown in FIG. 8, the oil recovery container 2
The gap portion 43 between the bottom portion of 8 and the lower end surface of the eccentric weight 29 may be smaller than the gap portion 44 between the outer peripheral portion of the oil recovery container 28 and the outer end surface of the eccentric weight 29. In this case,
Since a large centrifugal force acts on the outer gap portion 43, there is no fear that the lubricating oil M will flow from the lower gap portion 42 through the gap 35 to the electric motor portion 16.

The eccentric weight and the oil recovery container described above can be combined appropriately, and the example of the hermetic electric scroll compressor has been described above. For example, a hermetic rotary compressor can be used. Even if it is applied to other hermetic electric compressors, a sufficient effect can be obtained.

[0031]

Since the present invention is constructed as described above, the recovered lubricating oil does not flow out of the gap between the oil recovery container and the crankshaft to the electric motor section, and the crankshaft rotates. Since it moves accurately to the outer peripheral wall surface of the oil recovery container due to the centrifugal force, the scattering of the lubricating oil caused by flowing out to the electric motor part is prevented, and the amount mixed in the high pressure refrigerant gas to be discharged is reduced, The loss of pipe pressure during the refrigeration cycle caused by the lubricating oil mixed in the discharged high-pressure refrigerant gas and the decrease in heat exchange efficiency in heat exchangers such as condensers and evaporators are eliminated, and the compressor The reliability and the coefficient of performance will not decrease.

[Brief description of drawings]

FIG. 1 is a sectional view of a hermetic scroll compressor according to an embodiment of the present invention.

FIG. 2 is a schematic diagram of an oil recovery unit of the hermetic scroll compressor.

FIG. 3 is a sectional view taken along line AA of FIG.

FIG. 4 is a schematic diagram of a modified example of an oil recovery unit of the hermetic scroll compressor.

5 is a cross-sectional view taken along the line BB of FIG.

FIG. 6 is a schematic diagram of another modification of the oil recovery unit of the hermetic scroll compressor.

FIG. 7 is a schematic diagram of another modification of the oil recovery unit of the hermetic scroll compressor.

FIG. 8 is a schematic diagram of yet another modified example of the oil recovery unit of the hermetic scroll compressor.

FIG. 9 is a sectional view of a conventional hermetic scroll compressor.

[Explanation of symbols]

 1 Compression Mechanism 9 Sealed Container 12 Crank Shaft 16 Electric Motor 28 Oil Recovery Container 29 Eccentric Weights 33, 36, 37 Inclined Surface 38 Conical Bottom 40 Steps 43, 44 Gap M Lubricating Oil

 ─────────────────────────────────────────────────── ─── Continued front page (72) Inventor Masahiro Tsubokawa 1006 Kadoma, Kadoma City, Osaka Prefecture Matsushita Electric Industrial Co., Ltd. (72) Inventor Sakai Manabu 1006 Kadoma, Kadoma City Osaka Prefecture 72) Inventor Toshiharu Yasu 1006 Kadoma, Kadoma City, Osaka Prefecture Matsushita Electric Industrial Co., Ltd.

Claims (6)

[Claims] 1. A hermetically sealed container for accommodating a compression mechanism portion and an electric motor portion for driving the compression mechanism portion via a crankshaft, and an eccentric weight attached to the crankshaft at a lower portion of the compression mechanism portion. And a lubricating oil recovery part having an oil recovery container surrounding the eccentric weight is formed, and the lubricating oil recovery part is provided with a moving means for moving the lubricating oil to the outer peripheral wall part of the oil recovery container. Type electric compressor. 2. The hermetic electric compressor according to claim 1, wherein the eccentric weight has an end surface portion provided with an inclined surface which is inclined upward with respect to the axial direction of the crankshaft, and is used as a moving means. 3. The hermetic electric compressor according to claim 1, wherein the end surface portion of the eccentric weight is provided with an inclined surface inclined with respect to the radial direction of the crankshaft to serve as a moving means. 4. The closed type according to claim 1, wherein the bottom portion of the oil recovery container is a moving means in parallel with the lower end surface of an eccentric weight whose outer peripheral portion is thicker than the central portion. Electric compressor. 5. The hermetic electric compressor according to claim 1, wherein a step portion is provided on an outer peripheral wall portion of the oil recovery container as a moving means. 6. A moving means provided with a gap smaller than the gap between the outer periphery of the oil recovery container and the outer end face of the eccentric weight between the bottom of the oil recovery container and the lower end face of the eccentric weight. The hermetic electric compressor according to any one of claims 1 to 5.