JPH0518373A - Scroll compressor - Google Patents

Abstract

PURPOSE:To provide a scroll compressor capable of working with silence and efficiently decreasing pulsation sound generated when high pressure compression gas is discharged to a cavity part inside a valve cover from a discharge hole. CONSTITUTION:At an eccentric part of a rotary shaft 6 a discharge path 12 for discharging and guiding gas compressed at a compression space 15 is formed in the axial direction of the eccentric part 6b, and a discharge hole 18 communicating this discharge path with the outer circumferential face of rotational shat eccentric part 6b so as to discharge and guide the compression gas guided from the discharge path to the outside of the rotatational shaft 6 is formed. The opening circumference of the discharge hole 18 except a cavity part 21 is surrounded by a valve cover 20 for once collecting the compression gas discharged form the discharge hole 18. Each discharge hole 18 is set such that the size of angle in the rotational direction connecting the center of the opening of each discharge hole to the center of rotational shaft becomes an value of no integar time.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a scroll type compressor used in, for example, a refrigeration cycle apparatus to compress a refrigerant gas.

[0002]

2. Description of the Related Art Among compressors for a refrigerant gas used in a refrigeration cycle apparatus, in particular, the sealability is improved to enable efficient compression, and a valve mechanism is unnecessary to reduce the number of parts. Scroll compressors tend to be used frequently.

A scroll compressor is, for example, housed in a hermetically sealed case with its axis oriented in the vertical direction, and its lower and upper ends are rotatably supported by bearings, and a rotary shaft. It is composed of a scroll compression mechanism portion that is provided below the rotary shaft and that sucks and compresses a refrigerant gas, and an electric motor portion that is provided on the rotary shaft.

The scroll compression mechanism portion is a combination of an orbiting scroll blade that engages with an eccentric portion formed at the lower part of the rotating shaft and is capable of orbital movement, and a fixed scroll blade that is fixedly connected to a support frame that is a bearing tool. Consists of.

These orbiting scroll blades and fixed scroll blades each consist of a spirally formed blade portion and an end plate portion integrally formed with this blade portion, which mesh with each other and are surrounded by them. A compression space (compression chamber) is formed.

Along with the orbiting movement of the orbiting scroll blade, the refrigerant gas is sucked into the compression chamber on the outer peripheral side. This compression chamber gradually narrows its volume and moves to the center. When the compression chamber has moved to the center, the refrigerant gas is compressed to a predetermined pressure, and the boss of the orbiting scroll blade discharges the discharge passage provided in the eccentric portion and the discharge passage communicating the discharge passage and the peripheral surface of the eccentric rotating shaft. It is designed to be discharged into the closed case through the hole.

[0007]

By the way, in this type of scroll compressor, since the refrigerant gas is intermittently discharged into the closed case from the discharge passage and the discharge hole, the discharge noise in the closed case remains as it is. Will expand and become driving noise.

Therefore, a valve cover is provided which surrounds the opening of the discharge passage with a cavity.
The compressed refrigerant gas is temporarily collected in the hollow portion inside the valve cover to adjust the pressure, and is discharged into the sealed case from a small hole provided in the valve cover or a narrow gap between the valve cover and the rotating shaft. ..

As shown in FIG. 7 (A), conventionally, a rotary shaft (actually, an eccentric portion, but since it is schematically shown in the drawing,
The periphery of a (illustrated in a perfect circle) a is surrounded by a valve cover c via a cavity b.

The hollow portion of the rotary shaft a is formed as a discharge passage d, and a discharge hole e is opened through the wall thickness in the radial direction. That is, the discharge hole e connects the discharge passage d and the inside of the valve cover c.

The refrigerant gas compressed in the compression chamber is guided from the discharge passage d into the valve cover c through the discharge hole e, where the pressure is regulated. Further, it is guided to the outside through a gap (not shown) between the valve cover c and the peripheral surface of the rotary shaft a.

However, since the refrigerant gas is intermittently discharged from the discharge hole e, it flows as a pulsating flow in the cavity b. This pulsating flow propagates in the valve cover c in the circumferential direction, for example, in the counterclockwise direction, as shown by the arrow in the figure.

Then, after propagating through 360 °, the discharge hole e is again generated.
When returning to, since there is almost no attenuation, it becomes almost the same as the original pulsation value. As a result, as shown by + and-in the figure, positive pulsation is present near the ejection hole e, and negative pulsation is present near the position 180 ° opposite to the opening of the ejection hole e.

On the other hand, since the rotary shaft a is rotating, the discharge hole e is naturally rotated. Therefore, the standing pulsation due to the compressed refrigerant gas also spatially rotates at the rotation speed of the rotation axis a. When measured at a certain position, the pressure pulsation changes in an accurate alternating pattern of +, −, +, −, ... As shown in FIG. 7B, which causes a problem that the pulsation sound leaks to the outside.

The present invention has been made under such circumstances, and an object of the present invention is to efficiently dampen a pulsating sound when a compressed compressed gas is discharged from a discharge hole into a valve cover. The object is to provide a scroll type compressor that enables a quiet operation.

[0016]

In order to achieve the above-mentioned object, the present invention has an eccentric portion of a rotary shaft which is engaged with an orbiting scroll blade so as to be capable of orbital movement, and the orbiting scroll blade and a fixed scroll blade are meshed with each other. The compressed gas is sucked and compressed in the compression space formed between them, and a discharge passage is provided in the axial direction in the eccentric part of the rotary shaft to discharge and guide the gas compressed in the compression space. The compressed gas in the discharge passage is discharged and guided to the outside of the rotating shaft by communicating with the outer peripheral surface of the eccentric part through the discharge hole, and the discharge hole is surrounded by a valve cover that surrounds the opening and is discharged from the discharge hole. A plurality of discharge holes are provided and the size of the angle in the direction of rotation that connects the center of each discharge hole and the center of the rotation axis is set to a value other than an integral multiple. The scroll that is characterized by It is an expression compressor.

[0017]

The magnitude of the angle in the rotation direction, which connects the center of the rotation axis and the center of the rotation axis of the plurality of discharge holes, is set so as not to be an integral multiple of each other. In other words, they are set so that they are not integral multiples of each other. Therefore, the pressure waves of the compressed gas emitted from the respective discharge holes propagate in the valve cover while interfering with each other, and eventually, the pressure waves of each other cancel each other out to be attenuated to reduce the pulsating noise.

[0018]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings.

As shown in FIG. 1, 1 is a vertically long closed casing.
A support frame 2 is provided below the closed case 1, and a main bearing 3 is supported by the support frame 2. A sub-bearing frame 4 is attached and fixed to the upper part of the inner peripheral surface of the sealed case 1, and a sub-bearing 5 is provided therein.

A rotary shaft 6 is rotatably supported between the main bearing 3 and the sub bearing 5. The rotating shaft 6 has its axial direction oriented in the vertical direction, and has a lower end portion pivotally supported by the main bearing 3 and an upper end portion pivotally supported by the sub bearing 5.

An upper portion of the rotary shaft 6 is a main shaft portion 6a having a small diameter, and an electric motor portion 7 is provided there. The electric motor unit 7 includes a rotor 8 fitted to the rotary shaft 6, and a stator 9 having an inner peripheral surface having a narrow gap with the peripheral surface of the rotor 8 and fitted to the sealed case 1. An inverter type that can control the frequency is adopted.

An eccentric portion 6b is formed below the main shaft portion 6a, and a scroll compression mechanism portion 10 is engaged with the eccentric portion 6b. That is, in the eccentric portion 6b, the eccentric hole portion 11 is provided on the lower end side with the position eccentric from the axial center of the rotary shaft 6 as the axial center, and the discharge passage 12 is provided on the upper side of the eccentric hole portion 11 along the axial direction. It will be serialized.

The scroll compression mechanism section 10 includes an eccentric hole section 1.
It is composed of a combination of an orbiting scroll blade 13 having a boss portion 13a which is engaged with 1 to freely orbitally move, and a fixed scroll blade 14 which is fixedly connected to the support frame 2.

The orbiting scroll blade 13 and the fixed scroll blade 14 are composed of a spirally formed blade portion and an end plate portion integrally formed with the blade portion, which mesh with each other, The compression chamber 15 which is the surrounding compression space
To form. With the orbiting movement of the orbiting scroll blade 13, the compression chamber 15 is gradually narrowed in its volume and moved to the central portion.

As shown in an enlarged view in FIG. 6, a discharge port 16 is provided in the end plate portion of the orbiting scroll vane 13 facing the center of the compression chamber 15, and the discharge port 16 further has an axial center of the boss portion 13a. Gas discharge passage 17 provided along
Communicate with each other.

The axis of the gas discharge passage 17 of the boss 13a is
It coincides with the axial center of the eccentric hole portion 11 and the discharge passage 12. A discharge hole 18, which will be described later, is provided in the middle of the discharge passage 12 in the radial direction, penetrating the remaining thickness of the eccentric portion 6b.

That is, two discharge holes 18 are provided as shown in FIG. A line connecting the axes of the first discharge holes 18a, the center O of the rotary shaft 6 and the second discharge holes 18b.
The angle formed by the line connecting the axis centers of is in the direction of rotation of the rotary shaft 6 is called θ1, and the angle in the opposite direction of rotation is called θ2. This θ2 corresponds to 360 ° −θ1. θ with respect to θ2
1 must be set to be a multiple other than an integral multiple, in other words, not an integral multiple.

As shown in FIGS. 5 and 6, the lower end of the valve cover 20 is fixedly attached to the support frame 2. The valve cover 20 surrounds the rotary shaft eccentric portion 6b with a gap, is reduced to a small diameter on the upper side, and is slightly below the electric motor rotor 8, and its inner peripheral edge is the rotary shaft 6 peripheral surface. A lid portion 20a having a narrow gap is formed. A hollow portion 21 is formed in the valve cover 20.

An oil separating plate 22 is provided on the surface of the valve cover 20 which has a small diameter. The inner peripheral edge of the oil separating plate 22 has a small gap that does not come into contact with the peripheral surface of the rotating shaft eccentric portion 6b when it eccentrically rotates.

When the inner diameter of the large diameter portion of the valve cover 20 on the discharge passage 12 side is Dφ and the diameter of the inner peripheral edge of the oil separating plate 22 on the downstream side of the discharge passage 12 is φd, the relationship of D> d is satisfied. ..

On the other hand, the boss portion 13 of the orbiting scroll blade 13
A thrust ring 23 is provided at a position where there is a gap from the a peripheral surface, and between the rear surface side of the end plate portion of the orbiting scroll blade 13 and the lower surface of the main bearing 3. This thrust ring 2
3, the Oldham ring 24 is provided between the supporting frame 2 and the rear side of the end plate portion of the orbiting scroll blade 13 at the further circumferential end portion.
Is installed.

A suction pipe 25, which communicates with an evaporator (not shown) of the refrigeration cycle apparatus, is provided penetrating the side of the closed case 1, and the open end of the suction scroll blade 13 and the fixed scroll blade 14 is provided. It faces the outer peripheral side of the compression chamber 15, which is a meshing space.

On the other hand, a discharge pipe 26 communicating with a condenser (not shown) of the refrigeration cycle device is connected to the upper end of the closed case 1. The discharge pipe 26 communicates with the inside of the closed case 1.

Therefore, the electric motor 7 is energized to turn the rotary shaft 6
When is driven to rotate, the orbiting scroll vanes 13 engaged with each other via the eccentric hole portion 11 make an orbiting motion, and the refrigerant gas which is a low pressure compressed gas is sucked into the compression chamber 15 from the suction pipe 25 and compressed.

When the compression chamber 15 moves to the center, the refrigerant gas rises to a predetermined pressure and the discharge port 16
And is guided to the gas discharge passage 17 from here. Further, it is discharged into the hollow portion 21 in the valve cover 20 through the discharge passage 12 and the discharge hole 18.

The high pressure refrigerant gas is regulated in pressure, and the cavity 2 in the valve cover 20 is provided for the reason described below.
The pressure pulsation of the high-pressure refrigerant gas in No. 1 is reduced, and noise can be reduced.

The high-pressure refrigerant gas passes through the gap between the inner peripheral edge of the oil separation plate 22 provided inside the valve cover 20 and the outer peripheral surface of the eccentric portion 6b. The inner diameter of the large diameter part of the valve cover 20 is D
φ and the diameter of the inner peripheral edge of the oil separation plate 22 is φd, D
Since the relationship is> d, the lubricating oil component contained in the discharged refrigerant gas is efficiently separated.

Pure high-pressure refrigerant gas containing almost no lubricating oil is guided into the closed case 1 from between the valve cover 20 and the eccentric portion 6b. Then, it rises to the upper inside of the closed case 1 through a clearance between the rotor 8 and the stator 9 of the electric motor section 7 and a clearance hole (not shown) provided in the stator 9, and finally reaches the discharge pipe 26 at the upper end of the closed case 1. Is discharged to the condenser of the refrigeration cycle.

The discharge hole 18 is, as shown in FIG.
Two of the first discharge holes 18a are provided, and the second discharge holes 18b are opened at positions where an angle of θ1 exists in the rotation direction of the rotary shaft 6 with respect to the first discharge holes 18a, and θ2 (360 °) in the opposite rotation direction. −θ
The angle is 1). θ2 with respect to θ1 is set to be a multiple other than an integral multiple, that is, not to be an integral multiple.

The high-pressure refrigerant gas is supplied to the first and second discharge holes 1
By being guided to be discharged into the valve cover 20 from 8a and 18b, the cavity 21 in the valve cover 20 has a pressure distribution as shown in FIG. 1B along the circumferential direction.
That is, the pressure waves discharged from the first and second discharge holes 18a and 18b are mutually opposite to each other.
It propagates through the cavity 21 inside the valve cover 20 while interfering with the pressure wave emitted from b.

The angle θ formed by the discharge holes 18a and 18b.
Since 1 and θ2 are not integral multiples along the rotation direction, they cancel each other little by little. When the cavity 21 in the valve cover 20 is rotated several times, the pressure itself, which is the pressure width, is significantly attenuated due to the effect of the rotation. Therefore, the pressure pulsation is quickly reduced.

In the above embodiment, two discharge holes 18 such as the first and second discharge holes 18a and 18b are provided to reduce the pulsating noise, but the present invention is not limited to this. is not. As shown in FIG. 2A, even if the first to third ejection holes 28a to 28c are provided, the same operational effect is obtained.

That is, the sizes of the rotation direction angles θ1, θ2, and θ3 connecting the centers of the discharge shafts 28a to 28c from the center of the rotation shaft 6 are set so as not to be integral multiples of each other. As shown in FIG. 2B, the pressure waves discharged from the first to third discharge holes 28a to 28c interfere with the pressure waves emitted from the other discharge holes 28a to 28c, and the valve cover 20. Inner cavity 2
Propagate 1.

Since the angles θ1 to θ3 formed by the respective discharge holes 28a to 28c are not integral multiples of each other along the rotation direction, they cancel each other little by little. When the cavity 21 in the valve cover 20 is rotated several times,
The effect immediately and remarkably appears, and the pressure itself, which is the pressure range, is remarkably attenuated. Therefore, the pressure pulsation is reduced more quickly.

In these examples, the discharge hole 1
The cross-sectional shape of 8a, ..., 28a, ... Is an ordinary round hole, and the center of this opening is provided so as to be in the direction of the normal line to the outer peripheral curved surface of the rotating shaft 6, but is not limited to this. As shown in FIG. 3, the centers of the discharge holes 38a to 38c may be provided in a direction different from the outer peripheral surface of the rotary shaft 6 and the normal direction. Further, even if the cross-sectional shape of each of the discharge holes 38a to 38c is not only a perfect circle but also an irregular shape such as an ellipse or a star, the same action and effect can be obtained.

Further, as shown in FIG. 4, another component 27 may be fitted on the peripheral surface of the rotary shaft 6. In the rotating shaft 6, the center and the opening direction of the first to third discharge holes 48a to 48c are provided in the normal direction, and in the separate component 27, the first and third discharge holes 48a and 48c are in the normal direction. In a direction different from that, and communicates with the opening of the rotary shaft 6.
The second ejection hole 48b coincides with the normal direction.

Definitions of the angles θ1, θ2, θ3 in the rotation direction of the opening of the peripheral surface of the separate part 27 are allotted at a full circumferential angle of 360 ° with respect to the lengths L1, L2, L3 along the circumferential direction. Angle. That is, θ1 = (L1 / L1 + L2 + L3) × 3
60 θ2 = (L2 / L1 + L2 + L3) × 360 θ3 = (L3 / L1 + L2 + L3) × 360 With this configuration, the same effect as that of the above embodiment can be obtained.

The scroll compressor is used not only in the refrigeration cycle apparatus but also in other applications, and various modifications can be made within the scope of the present invention.

[0049]

As described above, according to the present invention, a plurality of discharge holes are provided, and the size of the rotation direction angle connecting the center of each discharge hole and the center of the rotation axis is not an integral multiple of each other. Therefore, when compressed gas is discharged from the discharge hole to the cavity inside the valve cover,
The pulsating sound that is generated is efficiently attenuated, and there is an effect that silent operation is performed.

[Brief description of drawings]

FIG. 1A is a transverse cross-sectional view of a main part of a scroll compressor, showing an embodiment of the present invention. (B) is a step pressure distribution in the circumferential direction in the valve cover.

FIG. 2A is a cross-sectional view of a main part of a scroll compressor, showing another embodiment. (B) is a step pressure distribution in the circumferential direction in the valve cover.

FIG. 3 is a cross-sectional view of a main part of a scroll compressor according to another embodiment.

FIG. 4 is a transverse cross-sectional view of a main part of a scroll compressor according to another embodiment.

FIG. 5 is a vertical cross-sectional view of a scroll compressor.

FIG. 6 is an enlarged vertical sectional view of a main part of a scroll compressor.

FIG. 7A is a cross-sectional view of a main part of a scroll compressor, showing a conventional example. (B) is a step pressure distribution in the circumferential direction in the valve cover.

[Explanation of symbols]

6 ... Rotating shaft, 6b ... Eccentric part, 13 ... Orbiting scroll blade,
15 ... compression space (compression chamber), 14 ... fixed scroll blade,
12 ... Discharge passage, 18 ... Discharge hole, 21 ... Hollow part, 20 ...
Valve cover.

Claims (1)

Claim: What is claimed is: 1. A compressed gas is sucked into an orbiting scroll blade which is engaged with an eccentric portion of a rotating shaft and is capable of orbital movement, and a compression space which is meshed with the orbiting scroll blade and formed between them. , A fixed scroll vane that is compressed by the discharge shaft, a discharge passage that is provided in the eccentric portion of the rotating shaft in the axial direction and that guides the discharge of the gas compressed in the compression space, and the discharge passage communicates with the outer peripheral surface of the rotating shaft eccentric portion. A discharge hole for discharging and guiding the compressed gas in the passage to the outside of the rotating shaft, and a valve cover for surrounding the opening of the discharge hole with a hollow portion to temporarily collect the compressed gas discharged from the discharge hole. The scroll compressor is characterized in that a plurality of the above-mentioned discharge holes are provided and the magnitude of the rotation direction angle connecting the center of the opening of each discharge hole and the center of the rotation axis is set to a value other than an integral multiple of each other. ..