JP2001248577A - Scroll type fluid machine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a scroll type fluid machine capable of sufficiently separating a lubricating oil. SOLUTION: This scroll type compressor (fluid machine) is provided with a compression mechanism C housed inside a sealed housing 15 for sucking a refrigerant and compressing the sucked refrigerant at high pressure so as to discharge it, a high pressure chamber 44 temporarily storing the refrigerant discharged from the compression mechanism C, and a discharge tube 18 opened to the high pressure chamber 44 and provided with a discharge port 18a for discharging the refrigerant to the outside of the housing. In this compressor, an injection pipe 45 discharging the refrigerant from the compression mechanism C to the inside of the high pressure chamber 44 in the horizontal direction substantially is arranged, and the discharge port 18a is positioned below the opening part the injection pipe 45 so as to be opened to the high pressure chamber 44.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a scroll type fluid machine used for an air conditioner or the like.

[0002]

2. Description of the Related Art An example of a conventional scroll type compressor (scroll type fluid machine) is disclosed in Japanese Patent Application Laid-Open No. 8-151990. The schematic structure of this scroll compressor is shown in FIGS. In the drawing, reference numeral 1 denotes a housing, 2 denotes a fixed scroll, and 3 denotes a turning scroll. A compression chamber 4 is formed by meshing the fixed scroll 2 and the orbiting scroll 3. The housing 1 is provided with a suction pipe 5a through which the refrigerant is sucked, and a discharge pipe 5b through which the compressed high-pressure refrigerant is discharged. Also,
A discharge hole 6 is provided at the center of the fixed scroll 2. A motor 7 is provided below the housing 1, and power is transmitted to the orbiting scroll 3 by a rotating shaft 8. When the motor 7 rotates, the orbiting scroll 3
Perform a revolving motion, and the refrigerant is sucked from the suction pipe 5 a and introduced into the compression chamber 4.

Here, the bottom of the housing 1 is
The lubricating oil is sucked up by an oil pump (not shown) provided at the lower end of the rotating shaft 8 with the rotation of the rotating shaft 8 and passes through an oil passage (not shown) in the rotating shaft 8. And supplied to each sliding portion. A part thereof is mixed into the refrigerant and is sucked into the compression chamber 4, and has an effect of enhancing the sealing effect of the compression chamber 4. The refrigerant introduced into the compression chamber 4 is gradually compressed and discharged from the discharge holes 6 as the orbiting scroll 3 revolves. The discharged high-pressure refrigerant is blown out to the upper part of the housing 1 by the injection pipe 9.

Here, if the refrigerant is discharged from the housing 1 as it is, the following problem occurs. That is, since lubricating oil is mixed in the refrigerant, there is a problem that the efficiency of heat exchange is reduced in the heat exchanger to which the refrigerant is supplied after discharge. Also, when the lubricating oil flows out, the amount of lubricating oil in the oil reservoir 10 becomes insufficient, and there is a possibility that the lubrication of each sliding portion becomes insufficient. For this reason, by adopting the following configuration, the lubricating oil mixed in the refrigerant is separated in the housing 1. That is, as shown in FIG. 7, the injection pipe 9 jets the refrigerant in a tangential direction of the inner wall of the housing 1, and the jetted refrigerant makes a circular motion along the inner wall of the housing 1. The lubricating oil is separated from the refrigerant by the centrifugal force due to the circular motion of the refrigerant. The separated lubricating oil falls by gravity and returns to the oil reservoir 10 via the oil return oil passage 11.

[0005]

However, in the conventional scroll compressor, the opening 9a of the injection pipe 9 is located below the opening 5c of the discharge pipe 5b. For this reason, the lubricating oil scattered in the discharge chamber may be unilaterally sucked into the discharge pipe 5b, and the lubricating oil may be discharged without being sufficiently separated from the refrigerant. For this reason, despite the adoption of the above-described structure, the above-described problem that the efficiency of the heat exchanger is still lowered cannot be completely solved. Then, in order to prevent the shortage of the lubricating oil, it is necessary to prepare extra lubricating oil in order to compensate for the amount of the lubricating oil discharged together with the refrigerant, resulting in an increase in weight.

The present invention has been made in view of the above circumstances, and is characterized by providing a scroll-type fluid machine capable of sufficiently separating lubricating oil.

[0007]

According to a first aspect of the present invention, there is provided a scroll type fluid machine, comprising: a housing; a compression mechanism which is housed in the housing, sucks the refrigerant, compresses the sucked refrigerant to a high pressure, and discharges the refrigerant; In a fluid machine having a high-pressure chamber in which the refrigerant discharged from the compression mechanism is temporarily stored, and a discharge port opened to the high-pressure chamber and discharging the refrigerant outside the housing, from the compression mechanism to the high-pressure chamber An injection pipe through which a refrigerant is discharged in a substantially horizontal direction, wherein the discharge port is
It is characterized by being located below the opening of the injection pipe and opening to the high-pressure chamber.

In this scroll type fluid machine, the discharge port is located below the opening of the injection pipe, so that the lubricating oil is sufficiently separated unlike the conventional scroll type compressor. After that, the refrigerant is discharged from the discharge port. Hereinafter, this operation will be described. As shown in FIG. 5A, in the conventional scroll-type fluid machine, the refrigerant blown out from the injection pipe 9 into the high-pressure chamber rises relatively smoothly while turning, and is discharged through the discharge pipe 5b. . On the other hand, as in the example shown in FIG. 2B, in the present invention, the refrigerant blown out from the injection pipe 45 collides with the discharge pipe 18 having the discharge port 18a after turning in the high-pressure chamber 44. . The post-impact refrigerant flow has a circumferential component and an axial component. The refrigerant flow f1 flowing downward in the axial direction further collides with the surrounding cover 41 or the rear surface of the fixed scroll 36, wraps around in a U-shape as shown in the figure, and is discharged from the discharge pipe 18. At this time, the lubricating oil contained in the refrigerant is separated from the refrigerant by the separation effect of the refrigerant colliding with the discharge pipe 18, the surrounding cover 41, or the fixed scroll 36.
As described above, in the present invention, not only the separating action by turning but also the separating action by collision works, so that the separating effect of the lubricating oil is larger than that of the conventional scroll type fluid machine.

According to a second aspect of the present invention, there is provided the scroll type fluid machine according to the first aspect, wherein an oil reservoir for storing lubricating oil is provided at the bottom of the housing, and one end is formed at the bottom of the high pressure chamber. And an oil return oil passage which is open at the other end and opens to face the oil reservoir.

In this scroll type fluid machine, the separated lubricating oil is returned to the oil reservoir via the oil return oil passage.

According to a third aspect of the present invention, there is provided a scroll type fluid machine according to the first aspect, wherein one end is opened at the bottom of the high-pressure chamber and the other end is opened at the flow path of the refrigerant. An oil passage is provided.

In this scroll type fluid machine, the separated lubricating oil is mixed with the refrigerant again, so that the lubricating oil can be supplied to each part of the apparatus system with the flow of the refrigerant. Examples of the flow path of the refrigerant include a refrigerant suction port of a compression mechanism and a compression chamber in which the refrigerant is compressed.

The discharge port for discharging the refrigerant from the compression mechanism may be provided with a surrounding cover surrounding the discharge port, and the surrounding cover may be provided with the injection pipe. further,
It is also effective to provide a discharge valve at the discharge port.

[0014]

Next, embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a diagram showing an overall configuration of a scroll compressor (scroll type fluid machine) of the present embodiment. In FIG. 1, reference numeral 15 denotes a closed housing, in which a refrigerant is sucked from a suction pipe 17 and discharged from a discharge pipe 18. Sealed housing 15
, A compression mechanism C is provided at an upper part thereof, and a motor M is provided at a lower part thereof.
Are housed and installed, and these are linked to each other via a rotating shaft 19. The scroll compression mechanism C includes a fixed scroll 21, an orbiting scroll 22, and an Oldham link 23 that allows the orbiting movement of the orbiting scroll 22 but prevents its rotation.

Fixed scroll 21 and orbiting scroll 22
Are eccentric by a predetermined distance from each other and are engaged at an angle of 180 degrees to form a plurality of compression chambers P. The fixed scroll 21 includes an end plate 24
And a spiral wrap 25 erected on the inner surface thereof, and a suction hole 27 provided at the outermost end of the spiral wrap 25 and a discharge hole 28 provided at the center of the end plate 24. The orbiting scroll 22 includes an end plate 31 and a spiral wrap 32 erected on the inner surface thereof. The orbiting scroll 22 is supported on a frame 33. The frame 33 is fixed to the sealed housing 15, and the thrust surface 33a formed on the upper surface of the frame 33 and the back surface of the orbiting scroll 22 are in sliding contact with each other.
2 is supported. An oil groove 34 is formed in the thrust surface 33a. Further, a cylindrical hole 33 </ b> A formed in the center of the upper surface of the frame 33 is limited at the back surface of the orbiting scroll 22, and an oil reservoir 35 is formed. A boss 49 is erected on the outer surface of the lower part of the end plate 31 of the orbiting scroll 22,
An eccentric bush 50 has a slewing bearing 51 in the boss 49.
The eccentric pin 53 protruding from the upper end of the rotary shaft 19 is rotatably fitted into a hole formed in the eccentric bush 50 via a rotary shaft.

A discharge cover 36 covers the upper part of the scroll compression mechanism C.
And a discharge valve 38 that opens and closes the discharge port 37
Is provided. On the upper surface of the discharge cover 36, a surrounding cover 41 surrounding the discharge port 37 and the discharge valve 38 is provided. A valve surrounding chamber 42 is formed between the surrounding cover 41 and the discharge cover 36, and the surrounding cover 41 is formed. And between the surrounding cover 41 and the sealed housing 15 is a high-pressure chamber 44. Since the surrounding cover 41 has a smaller diameter than the closed housing 15, an annular groove 46 surrounding the surrounding cover 41 is formed around the surrounding cover 41 as shown in the figure.

An injection pipe 45 is attached to the surrounding cover 41. As shown in FIG. 1 and FIG.
The one end opening 45a (see FIG. 2) opens into the valve enclosure 42, and the other end opening 45b opens at a predetermined angle θ with respect to the tangential direction of the inner wall of the sealed housing 15. Here, θ is set to an acute angle. As shown in FIG. 2, when the refrigerant is injected into the closed housing 15 from the opening 45b, the flow rate is distributed to Q ₁ and Q ₂ by the injection angle θ (from the momentum conservation law, Bernoulli's formula). Flow rate ratio Q ₂ / Q _{1 is, Q 2 / Q 1 = (} 1-COSθ) / become (1 + COSθ). Therefore, if this ratio is sufficiently small, it is not always necessary to bend the tip of the injection pipe 45 in the tangential direction. Further, an oil return oil passage 47 having an upper end opening to the annular groove 46 and a lower end opening to an oil reservoir 60 described later is provided. The oil return oil passage 47 has a tubular shape and is provided so as to penetrate the fixed scroll 21 and the frame 33. The discharge pipe 18 is provided on the central axis of the closed housing 15,
The discharge port 18a, which is the lower end opening, opens in the high-pressure chamber 44. The opening position is below the opening 45 b of the injection pipe 45.

The bottom of the sealed housing 15 has an oil sump 60
And the lubricating oil is stored. An oil pump 61 of a positive displacement type is provided at the lower end of the rotating shaft 19, and a suction port (not shown) of the oil pump 61 has an oil reservoir 60.
Open inside. A discharge port (not shown) of the oil pump 61 communicates with an oil supply hole 62 formed in the rotary shaft 15. The upper end of the oil supply hole 62 is the orbiting scroll 2
2, and has an opening 62a.

The scroll compressor of the present embodiment having the above configuration operates as follows. By driving the electric motor M, the orbiting scroll 22 is driven via a revolving orbiting mechanism including the rotating shaft 19, the eccentric pin 53, the eccentric bush 50, the boss 49 and the like. The orbiting scroll 22 revolves in a circular orbit having a revolving radius of revolution while being prevented from rotating by the Oldham link 23. Then, the refrigerant gas enters the closed housing 15 via the suction pipe 17, passes through the gas passage (not shown) of the frame 33, and is sucked into the compression chamber P via the suction hole 27. Then, as the volume of the compression chamber P decreases due to the revolving orbiting motion of the orbiting scroll 22, the compression chamber P is compressed and reaches the center portion while being compressed.
to go into.

On the other hand, the lubricating oil is sucked up by the oil pump 61 by the rotation of the rotary shaft 19 from the oil sump 60, rises up the oil supply hole 62 and spouts out of the opening 62 a to lubricate the slewing bearing 51. Thereafter, the boss 43 is blown out around by turning. Then, a part thereof is mixed into the refrigerant and is taken into the compression chamber P from the suction hole 27 to lubricate the contact portion between the fixed scroll 21 and the orbiting scroll 22 and to enhance the sealing performance. The lubricating oil after lubrication enters the valve enclosure 42 via the discharge port 37 together with the refrigerant.

The refrigerant is supplied to the valve enclosure 42 by the injection pipe 45.
From the high-pressure chamber 44. As shown in FIG. 2, the refrigerant blown out from the opening 45b of the injection pipe 45 performs a circular motion, and the centrifugal force at this time separates the lubricating oil mixed in the refrigerant due to the density difference, Sealed housing 1
5 adheres to the inner wall. The attached lubricating oil falls into the annular groove 46 by gravity, passes through the oil return oil passage 47, and returns to the oil sump 60. After the refrigerant has swirled in the high-pressure chamber 44,
It collides with the discharge pipe 18 as shown in FIG. The post-impact refrigerant flow has a circumferential component and an axial component. The refrigerant flowing downward in the axial direction further collides with the surrounding cover 41 or the back surface of the fixed scroll 36, wraps around in a U-shape as indicated by reference numeral f <b> 1, and is discharged through the discharge pipe 18. At this time, the lubricating oil contained in the refrigerant is separated from the refrigerant by the separation effect of the refrigerant colliding with the discharge pipe 18, the surrounding cover 41, or the fixed scroll 36. After the separated lubricating oil is blown away in the radial direction, the lubricating oil merges with the coolant flowing in the annular groove 46 as shown at f2, is conveyed, and returns from the oil return oil passage 47 to the oil reservoir 60. The refrigerant from which the lubricating oil has been separated is discharged through the discharge pipe 18 to the outside of the closed housing 15 and then sent to a heat exchanger or the like.

As described above, in the scroll compressor of the present embodiment, since the discharge port 18a of the discharge pipe 18 is located below the opening 45b of the injection pipe 45, the lubricating oil separating effect due to the turning of the refrigerant flow. Not only that, a separation effect due to collision can be obtained. Therefore, since the lubricating oil is sufficiently separated and the lubricating oil is not sent to the heat exchanger, the efficiency of heat exchange is not reduced. Further, since the lubricating oil is not discharged from the compressor, the amount of lubricating oil in the oil sump 60 can be minimized, and the compressor can be reduced in weight.
In addition, by separating the refrigerant and the lubricating oil in the compressor in this way, it is not necessary to separately provide a device for that, and the system can be downsized. Furthermore,
The provision of the discharge valve 38 prevents the high-pressure refrigerant in the high-pressure chamber 44 from flowing backward when the compressor is stopped, and prevents the orbiting scroll 22 from rotating in the reverse direction. Therefore, the spiral wraps 25, 32 generated by the reverse rotation
, And insufficient lubrication to each sliding portion can be prevented.

As a modification of this embodiment, the following configuration may be adopted. As shown in FIG. 3, one end of the oil return oil passage 47 'is opened in the annular groove 46 in the same manner as described above, and the other end is connected to the suction hole 2.
Open at 7. With this configuration, the lubricating oil separated in the high-pressure chamber 44 is sucked into the compression chamber P again through the oil return oil passage 47 '. Thereby, the lubricating oil is supplied to the compression chamber P, the sealing performance is improved, and the refrigerant leakage in the compression chamber P can be prevented. Further, as shown in FIG. 4, the oil return oil passage 4 having the fixed scroll 21 penetrated therethrough.
The opening may be directly opened to the compression chamber P as in 7 ″. In this case, the same effect as the oil return oil passage 47 ′ can be obtained.

In each of the above examples, the tip of the injection pipe 45 is not bent, but may be bent as in the conventional example (see FIG. 7). In this case, by bending the tip of the injection pipe 45 toward the annular groove 46, the refrigerant blown out from the injection pipe 45 flows into the annular groove 46 smoothly. Since the cross-sectional area of the coolant flow in the annular groove 46 is kept small, it is expected that the speed of the coolant flow is prevented from sharply decreasing, and the lubricating oil separating effect is enhanced. However, since a large bending angle causes a pressure loss, it is desirable to bend without a sharp angle change.

[0025]

As described above, in the scroll type fluid machine of the present invention, since the discharge port is located below the opening of the injection pipe, the lubricating oil is sufficiently separated. Therefore, since no refrigerant is sent to the heat exchanger, the efficiency of heat exchange is not reduced. Further, since the lubricating oil is not discharged from the compressor, the amount of lubricating oil in the oil sump is required to be a minimum and the compressor can be reduced in weight.

[Brief description of the drawings]

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

FIG. 2 is a cross-sectional view of a high-pressure chamber portion of the scroll compressor.

FIG. 3 is a longitudinal sectional view showing a modified example of the scroll compressor.

FIG. 4 is a longitudinal sectional view showing a modified example of the scroll compressor.

FIG. 5 is a diagram comparing the flow of a refrigerant flow between a conventional scroll compressor and a scroll compressor according to an embodiment of the present invention.

FIG. 6 is a longitudinal sectional view of a conventional scroll compressor.

FIG. 7 is a cross-sectional view of the scroll compressor.

[Explanation of symbols]

 15 Sealed housing (housing) 18a Discharge port 21 Fixed scroll 22 Orbiting scroll 44 High pressure chamber 45 Injection tube 45b Opening 47 Oil return oil passage 60 Oil reservoir P Compression chamber C Compression mechanism

Claims (3)

[Claims] 1. A housing, a compression mechanism housed inside the housing, for sucking the refrigerant, compressing the sucked refrigerant to a high pressure and discharging, and a high-pressure chamber for temporarily storing the refrigerant discharged from the compression mechanism. A scroll-type fluid machine having a discharge port that opens into the high-pressure chamber and discharges refrigerant outside the housing, comprising: an injection pipe through which refrigerant is discharged in a substantially horizontal direction from the compression mechanism into the high-pressure chamber; The scroll-type fluid machine according to claim 1, wherein the discharge port is located below the opening of the injection pipe and opens to the high-pressure chamber. 2. The scroll-type fluid machine according to claim 1, wherein an oil reservoir for storing lubricating oil is provided at the bottom of the housing, one end of which is open to the bottom of the high-pressure chamber, and the other end of which is the oil reservoir. A scroll-type fluid machine, wherein an oil return oil passage is provided which opens toward the portion. 3. The scroll-type fluid machine according to claim 1, wherein an oil return oil passage is provided, one end of which opens at the bottom of the high-pressure chamber, and the other end of which opens to a flow path of the refrigerant. And scroll type fluid machinery.