JP2004360644A - Scroll fluid machinery - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide scroll fluid machinery capable of reducing compression loss caused by a delivery valve and facilitating the structure and installation of the delivery valve. <P>SOLUTION: This scroll compressor as fluid machinery comprises a drive unit 2 and a compression unit 4. The compression unit 4 comprises movable and fixed scrolls 34 and 36 stored in the casing 28 of the compression unit and forming a compression chamber 38 and the delivery valve 62 delivering compressed working gas from the compression chamber 38 to the delivery chamber 60 of the casing 28. The delivery valve 62 comprises a delivery hole 64 passed through the substrate 56 of the fixed scroll 36, a delivery valve element 64 stored in the delivery hole 64 to eliminate a dead space in the delivery hole 64, and a valve spring 78 installed across the delivery valve element 64 and the end wall of the casing 28. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a scroll type fluid machine, and more particularly to a scroll type fluid machine having an improved discharge valve.
[0002]
[Prior art]
This type of scroll type fluid machine, that is, a scroll type compressor, has a discharge valve as a check valve which allows discharge of the working gas compressed by a compression process, and the discharge valve is connected to a compression chamber in the compressor and a discharge chamber. It has a discharge hole formed through the center of the substrate of the fixed scroll to communicate with the chamber, and a reed valve element attached to the outer surface of the substrate on the discharge chamber side to open and close the discharge hole. In the reed valve body, the entire internal space of the discharge hole is left as a dead space in the process of compressing the working gas. Since the working gas in such a dead space is compressed again in the next compression process, a compression loss is caused, which causes an increase in power consumption of the compressor.
[0003]
For this reason, scroll-type compressors using a discharge valve capable of substantially eliminating dead space are also known (for example, Patent Documents 1 and 2), and the discharge valve of this known compressor is a reed. It has a discharge valve housed in the discharge hole instead of the valve body.
[0004]
[Patent Document 1]
JP-A-8-319973 [Patent Document 2]
JP-A-2002-364564
[Problems to be solved by the invention]
It is recognized that any of the discharge valve bodies disclosed in the above-mentioned publications open and close a valve opening of a discharge hole opened to a compression chamber in a closed position, but the discharge valve disclosed in the publication is a valve spring of the discharge valve body itself. The stopper is also accommodated in the discharge hole, and the valve spring is supported by a spring seat member attached to the fixed scroll substrate.
[0006]
Therefore, any of the discharge valves disclosed in the publication requires a separate spring seat member for the valve spring, which not only causes an increase in the number of parts of the entire fluid machine, but also greatly increases the assembly of the discharge valve. It takes time.
The present invention has been made on the basis of the above-described circumstances, and an object of the present invention is to eliminate the above-mentioned dead space in the discharge hole, and to easily reduce the number of parts and assemble the discharge valve. An object of the present invention is to provide a scroll type fluid machine.
[0007]
[Means for Solving the Problems]
In order to achieve the above object, the present invention provides a scroll type fluid machine comprising a casing accommodating a movable and a fixed scroll, wherein a substrate of the fixed scroll partitions the inside of the casing into a compression chamber side and a discharge chamber side. The discharge valve that opens and closes the discharge hole of the substrate is slidably inserted in the discharge hole in the axial direction of the discharge hole, fits into the valve hole of the discharge hole in the closed position, and closes the opening surface of the valve hole. A discharge valve body having a flow path connecting the valve port and the discharge chamber at the open position while having a valve body part to be closed, and disposed between the discharge valve body and the inner wall surface of the casing in the discharge chamber. And a valve spring for urging the discharge valve body toward the closed position.
[0008]
According to the scroll-type fluid machine described above, when the discharge valve is closed, the valve body of the discharge valve body is fitted into the valve port of the discharge hole and closes the opening surface of the valve port. There is no dead space. In this state, when the working gas is compressed in the compression chamber and the pressure of the working gas increases, the discharge valve body receives the pressure of the compressed working gas at the tip end surface of the valve body. When the pressure of the compressed working gas overcomes the urging force of the valve spring, the discharge valve slides in the discharge hole from the closed position to the open position, and opens the valve port of the discharge hole. Therefore, the compressed working gas is discharged from the compression chamber to the discharge chamber through the discharge valve. When the discharge operation of the compressed working gas is completed, the discharge valve body receives the urging force of the valve spring, returns from the open position to the closed position, and closes the valve port of the discharge hole.
[0009]
Specifically, the discharge valve further includes a spring retainer integrally projecting from the inner wall surface of the casing toward the substrate of the fixed scroll and having a spring accommodating chamber opened at the projecting end surface. The discharge valve body is pressed and urged while a part is housed in the spring housing chamber (claim 2). Such a spring retainer prevents buckling of the valve spring and stabilizes the opening and closing operation of the discharge valve.
[0010]
Further, it is preferable that a predetermined interval is secured between the projecting end surface of the spring retainer and the substrate of the fixed scroll, and the inner diameter of the spring accommodating chamber is smaller than the outer diameter of the discharge valve body. In this case, when the discharge valve body slides from the closed position to the open position, the sliding stops when the discharge valve body contacts the protruding end surface of the spring retainer. That is, the projecting end surface of the spring retainer functions as a stopper surface that defines the open position of the discharge valve body.
[0011]
Further, the discharge valve body has a plurality of radiation fins on its outer peripheral surface, these radiation fins are spaced in the circumferential direction of the discharge valve body, and the above-described flow paths are respectively formed between adjacent radiation fins. (Claim 4). In this case, the radiation fin guides the sliding of the discharge valve body when the discharge valve body opens and closes, and when the valve is opened, the compressed working gas in the compression chamber is discharged to the discharge chamber through a flow path formed between the radiation fins. You.
[0012]
BEST MODE FOR CARRYING OUT THE INVENTION
Referring to FIG. 1, a compressor as a scroll type fluid machine is shown. The scroll type compressor is roughly divided into a drive unit 2 and a compression unit 4.
The drive unit 2 includes a housing 6, which has a stepped cylindrical shape with a large diameter on the compression unit 4 side, and has both open ends. A rotating shaft 8 is disposed in the housing 6, and also has no stepped shape, and has a small-diameter shaft portion at one end and a large-diameter end 10 at the other end. The large-diameter end 10 is located on the large-diameter end side of the housing 6 and is rotatably supported by the housing 6 via a needle bearing 12. On the other hand, the small-diameter shaft portion of the rotating shaft 8 is also rotatably supported by the small-diameter end of the housing 6 via the ball bearing 14.
[0013]
A lip seal 16 is disposed between the ball bearing 14 and the needle bearing 10 in the housing 6. The lip seal 16 relatively slidably contacts the small-diameter shaft portion of the rotary shaft 8, and It is airtight.
Further, the small-diameter shaft portion of the rotating shaft 8 protrudes from the small-diameter end of the housing 6, and a drive disk 18 is attached to the protruding end via a nut 20. The drive disk 18 is connected to a drive pulley 24 via an electromagnetic clutch 22. The drive pulley 24 has a built-in solenoid of the electromagnetic clutch 22, and is rotatably supported by a small-diameter end of the housing 6 via a pulley bearing 26. I have.
[0014]
When the scroll compressor is installed in an air conditioning system of a vehicle, the drive pulley 24 is driven to rotate in one direction by receiving power from the vehicle engine, and the electromagnetic clutch 22 is driven from the drive pulley 24 by the drive disk 18, that is, the drive disk. The driving force transmitted to the rotating shaft 8 is interrupted. Therefore, when the electromagnetic clutch 22 is turned on, the electromagnetic clutch 22 integrally connects the drive pulley 24 and the drive disk 18, and rotates the drive disk 18, that is, the rotating shaft 8 together with the drive pulley 24 in one direction. On the other hand, when the electromagnetic clutch 22 is turned off, the electromagnetic clutch 22 releases the connection between the drive pulley 24 and the drive disk 14 and cuts off the transmission of power from the drive pulley 24 to the rotary shaft 8.
[0015]
On the other hand, the compression unit 4 includes a casing 28, and the casing 28 has a cup shape that opens toward the large-diameter end of the housing 6. The open end of the casing 28 is airtightly fitted to the large-diameter end of the housing 6 via a seal ring 30, and is connected to the large-diameter end of the housing 6 via a plurality of connection screws 32.
[0016]
A movable scroll 34 and a fixed scroll 36 that mesh with each other are accommodated in the casing 28. The spiral wraps 34a and 36a of the movable and fixed scrolls 34 and 36 cooperate with each other to form the compression chamber 38 via a seal. Form. The compression chamber 38 moves toward the center from the radially outer side of the spiral wraps 34a and 36a with the orbital movement of the orbiting scroll 34, and the volume thereof is reduced.
[0017]
In order to achieve the above-described orbiting movement of the orbiting scroll 34, the substrate 40 of the orbiting scroll 34 has a boss 42 protruding toward the housing 6, and the boss 42 is attached to the eccentric bush 46 via a needle bearing 44. It is rotatably supported. The eccentric bush 46 is supported by a crank pin 48, which eccentrically projects from the large-diameter end 10 of the rotating shaft 8. Accordingly, as the rotary shaft 8 rotates, the orbiting scroll 34 orbits through the crank pin 48 and the eccentric bush 46.
[0018]
A counterweight 50 is attached to the eccentric bush 46 so as to be sandwiched between the eccentric bush 46 and the large-diameter end 10 of the rotating shaft 8. The counterweight 50 has a plurality of large and small arc-shaped counterweights. It is configured by stacking plates, and serves as a balance weight for the orbiting movement of the movable scroll 34.
Further, a ball coupling 52 as a rotation preventing mechanism is interposed between the large diameter end of the housing 6 and the substrate 40 of the movable scroll 34. For example, the ball coupling 52 is supported by the large-diameter end of the housing 6 and the substrate 40, respectively, and has a pair of ring plates 54 having annular races at equal intervals in the circumferential direction, and an annular race of the ring plates 54. The ball 56 is interposed therebetween, and prevents the movable scroll 34 from rotating around the axis of the needle bearing 44.
[0019]
On the other hand, the fixed scroll 36 is fixed in the casing 28, and the substrate 58 partitions the inside of the casing 28 into the compression chamber 38 side and the discharge chamber 60, and between the substrate 58 and the end wall of the casing 28, which will be described later. A discharge valve 62 is provided.
Although not shown in FIG. 1, a suction port and a discharge port communicating with the compression chamber 38 and the discharge chamber 60 are formed on the peripheral wall of the casing 28.
[0020]
According to the above-described scroll compressor, the movable scroll 34 is eccentrically rotated through the crankpin 48 and the eccentric bush 46 in accordance with the rotation of the rotary shaft 8, and the movable scroll 34 is rotated by the ball coupling 52. , The rotation is prevented. As a result, the orbiting scroll 34 orbits with respect to the fixed scroll 36 while keeping the orbiting posture constant, and this orbiting movement sucks working gas from the suction port into the compression chamber 38, and Then, the compressed working gas is subjected to a compression process, and finally the compressed working gas is discharged into the discharge chamber 60 through the discharge valve 62, and thereafter, is discharged from the discharge chamber 60 through the outlet.
[0021]
Next, the above-described discharge valve 62 will be described in detail with reference to FIGS. 2A, the discharge valve 62 has a discharge hole 64 formed in the substrate 58 of the fixed scroll 34, and the discharge hole 64 penetrates the center of the substrate 58, and is compressed. The chamber 38 and the discharge chamber 60 communicate with each other. The end of the discharge hole 64 on the compression chamber 38 side is formed as a valve port 66, and the valve port 66 has a truncated conical shape that tapers toward the compression chamber 38.
[0022]
A discharge valve 67 made of synthetic resin is accommodated in the discharge hole 64, and the discharge valve 67 has an axial length equal to the thickness of the substrate 58 of the fixed scroll 34. The distal end of the discharge valve body 67 is formed as a valve body portion 68 that matches the valve port 66, and this valve body portion 68 also has a frustoconical shape.
Although the minimum outer diameter of the valve body portion 68 matches the minimum inner diameter of the valve port 66, its maximum outer diameter is smaller than the maximum inner diameter of the valve port 66, that is, the inner diameter of the discharge hole 64. Therefore, when the discharge valve body 67 is in the closed position shown in FIG. 2A, the distal end surface of the valve body portion 68 is accurately positioned on the opening surface of the valve port 66 with respect to the compression chamber 38, and There is no dead space connected to the compression chamber 38.
[0023]
Further, the discharge valve body 67 includes a slider 70 integrally connected to the valve body portion 68. The slider 70 has a central portion extending coaxially with the valve body portion 68 and a central portion as is clear from FIG. And four radiating fins 72 projecting radially outward from the fins 72. The radiation fins 72 are in sliding contact with the inner peripheral surfaces of the discharge holes 64, respectively. Therefore, the inner peripheral surfaces of the discharge holes 64 serve as guide surfaces for slidingly guiding the discharge valve body 66 via the radiation fins 72. .
[0024]
On the other hand, recesses extending in the axial direction of the discharge holes 64 are formed between the radiation fins 72, and these recesses are formed between the open valve port 66 and the discharge chamber 62 when the valve port 66 is opened. A flow path 74 that connects them is formed.
Since the axial length of the discharge valve body 67 is equal to the thickness of the substrate 58 of the fixed scroll 36 as described above, when the discharge valve body 67 is at the closed position shown in FIG. That is, the end surface of the slider 70 is positioned flush with the outer surface of the substrate 58 on the ejection chamber 60 side.
[0025]
Further, in each of the radiation fins 72, the end on the valve body portion 68 side is cut out, and even if the discharge valve body 67 is positioned at the closed position, the radiation fins 72 may not interfere with the valve port 66. Absent.
On the other hand, as shown in FIG. 1, a spring retainer 76 is integrally protruded from the end wall of the casing 28 toward the substrate 58 of the fixed scroll 36. The spring retainer 76 is disposed coaxially with the discharge hole 64 and has a cylindrical spring housing chamber 80 therein. The spring housing chamber 80 opens at a projecting end surface 77 of the spring retainer 76. A predetermined interval between the base plate 77 and the substrate 58 of the fixed scroll 36, specifically, an interval shorter than the axial length of the slider 70 in the discharge valve body 67 is secured. It has an outer diameter of the body 67, that is, an inner diameter smaller than the inner diameter of the discharge hole 64.
[0026]
A part of a valve spring 78 composed of a compression coil spring is accommodated in a spring accommodating chamber 80 of the spring retainer 76, and the valve spring 78 projects from the spring retainer 76 and abuts on the discharge valve body 67. That is, the valve spring 78 is bridged between the discharge valve body 67 and the end wall of the casing 28 to urge the discharge valve body 67 toward its closed position.
[0027]
According to the configuration of the discharge valve 62 described above, when the pressure of the working gas in the compression chamber 38 rises and this pressure overcomes the urging force of the valve spring 78, as shown in FIG. The inside of the discharge hole 64 slides, and the valve body portion 68 lifts from the valve port 66 of the discharge hole 64 to open the valve port 66. The sliding of the discharge valve body 67 is stopped when the slider 70 partially protruding from the substrate 58 of the fixed scroll 36 contacts the protruding end face 77 of the spring retainer 76. The opening 67 is a stopper that defines the lift distance L of the discharge valve body 67.
[0028]
Therefore, the compressed working gas in the compression chamber 38 is discharged into the discharge chamber 60 through the flow path 74 of the discharge valve body 67 from the open valve port 66.
Thereafter, when the pressing force of the valve spring 78 of the compressed working gas exceeds the pressure of the compressed working gas in the compression chamber 38 with the discharge of the compressed working gas, the discharge valve body 67 presses and presses the valve spring 78. When the inside of the discharge hole 64 is slid toward the valve port 66 by the force, and the valve body 68 closes the valve port 66, the discharge operation of the compressed working gas is completed.
[0029]
As is apparent from the above description, when the discharge valve body 67 is in the closed position, there is no dead space in the discharge hole 64 that adversely affects the compression of the working gas in the compression chamber 38. The compression loss of the compressor can be avoided, and the power consumption can be reduced.
In assembling the scroll compressor, the valve spring 78 is accommodated in the spring accommodating chamber 80 of the spring retainer 76, while the discharge valve body 67 is accommodated in the discharge hole 64 of the substrate 56 of the fixed scroll 36. By simply assembling the fixed scroll 36 in the casing 28 in this state, the assembling of the discharge valve 62 is also performed simultaneously with the assembling of the fixed scroll 36, and the assembling of the discharge valve 62 is facilitated.
[0030]
Further, since the casing 28 also serves as the spring seat member of the valve spring 78, the number of parts required for the discharge valve 62 and the cost can be reduced.
Since the sliding of the discharge valve body 67 between the closed position and the open position is guided by the inner peripheral surface of the discharge hole 64 via the slider 70, the opening and closing operation of the discharge valve 62 is stable, and Since the flow path 74 for discharging the compressed working gas into the discharge chamber 60 is formed in 70, the slider 70 does not hinder the discharge of the compressed working gas.
[0031]
In addition, when the valve spring 78 expands and contracts to allow the discharge valve body 67 to slide, the expansion and contraction of the valve spring 78 is guided by the spring retainer 76, so that the buckling of the valve spring 78 is reliably prevented.
Furthermore, since the projecting end surface 77 of the spring retainer 76 defines the open position of the discharge valve body 67, when the discharge valve 62 is opened, the discharge valve body 67, that is, the slider 70 thereof, protrudes excessively from the discharge hole 64. There is no. Accordingly, the slider 70 is always guided stably by the inner peripheral surface of the discharge hole 64, and the reliability of the opening and closing operation of the discharge valve 62 can be further improved.
[0032]
The present invention is not limited to the above-described embodiment, and various modifications are possible.
For example, the slider 70 of the discharge valve body 67 of the first modified example shown in FIGS. 4A and 4B has a plurality of cantilevered ridges 82 instead of the above-described radiation fins 72. These ridges 82 are spaced apart from each other in the circumferential direction of the slider 70 and extend from the valve body 68 in parallel with the axial direction. Specifically, the protrusions 82 are obtained by removing the central portion of the slider 70 shown in FIG. 2A and leaving only the radially outer portion of the radiation fin 72.
[0033]
In this case, as in the second modification shown in FIGS. 5A and 5B, the free end of the ridge 82 has a shape similar to the cross-sectional shape of the slider 70 shown in FIG. 2B. The thin end plates 84 may be integrally connected to each other.
The number of the radiation fins 72 is not limited to four, and may be three or four of the third and fourth modifications shown in FIGS. 6A and 6B. There is no restriction on the number of.
[0034]
It goes without saying that the discharge valve body 67 shown in FIGS. 3 to 6 also exerts the same operation and effect as the discharge valve body of one embodiment.
The discharge valve 62 of the fifth modified example shown in FIG. 7 has a discharge valve body 67 in which the maximum diameter of the valve body part 68 and the outer diameter of the slider 70 match. An annular groove 84 is formed on the peripheral surface adjacent to the valve port 66. The annular groove 84 allows communication between the valve port 66 and each flow path 74 when the discharge valve 62 is opened.
[0035]
The discharge valve 62 of the sixth modified example shown in FIG. 8 has a discharge valve body 67 extending between the discharge hole 64 and the spring accommodating chamber 80 of the spring retainer 76, and the discharge valve body 67 slides. Are guided by the discharge hole 64 and the inner peripheral surface of the spring accommodating chamber 80, respectively. In this case, as shown by a two-dot chain line in FIG. 8, the spring retainer 76 has a stopper rod 86 concentrically in the spring accommodating chamber 80, and the end face of the stopper rod 86 Specify the open position. Note that the stopper lot 86 extends integrally from the end wall of the casing 28.
[0036]
The cross-sectional shape of the above-described discharge hole 64 and the discharge valve body 67 is basically circular, but may be other shapes such as a rectangle, or may have a stepped shape when viewed in the axial direction. None, the guide surface defined by the inner peripheral surface of the discharge hole 64, and the sliding contact surface of the discharge valve body 67 with the guide surface may be divided in the axial direction.
Lastly, each of the above-described discharge valve bodies 67 is not limited to a synthetic resin, but may be made of metal.
[0037]
【The invention's effect】
As described above, according to the scroll-type fluid machine of the present invention (claim 1), when in the closed position, the valve body portion of the discharge valve body does not provide a dead space in the discharge hole, and the valve of the discharge hole does not have a dead space. Since the mouth is closed, there is no compression loss due to the dead space, and power consumption can be reduced. Further, since the valve spring is disposed between the inner wall surface of the casing as a spring seat and the discharge valve body, a spring seat member only for the valve spring is unnecessary, and the number of parts is reduced. Reduction can be achieved, and the discharge valve can be easily assembled.
[0038]
Further, since the valve spring is housed in a spring retainer integral with the casing (claim 2), buckling of the valve spring is reliably prevented, and the opening and closing operation of the discharge valve can be stabilized.
Further, since the spring retainer also functions as a stopper for defining the open position of the discharge valve body (claim 3), the number of parts can be reduced from this, while contributing to stabilization of the opening and closing operation of the discharge valve. .
[0039]
Furthermore, when a plurality of radiation fins are provided on the discharge valve body (claim 4), sliding of the discharge valve body is guided by these radiation fins, and when the discharge valve is opened, the inside of the compression chamber is opened. The compressed working gas can be discharged into the discharge chamber through the passage between the radiation fins.
[Brief description of the drawings]
FIG. 1 is a longitudinal sectional view showing a scroll type compressor according to one embodiment.
FIG. 2A is an enlarged view of a part of the discharge valve of FIG. 1, and FIG. 2B is a rear view of the discharge valve body shown in FIG.
FIG. 3 is a view showing a discharge valve in an open state.
4A and 4B show a discharge valve body of a first modified example, in which FIG. 4A is a side view and FIG. 4B is a rear view.
FIGS. 5A and 5B show a discharge valve body of a second modified example, in which FIG. 5A is a side view and FIG. 5B is a rear view.
FIG. 6A is a rear view of a discharge valve body according to a third modified example, and FIG. 6B is a rear view of a discharge valve body according to a fourth modified example.
FIG. 7 is a view showing a discharge valve according to a fifth modified example.
FIG. 8 is a view showing a discharge valve according to a sixth modification.
[Explanation of symbols]
28 Casing 34 Movable scroll 36 Fixed scroll 38 Compression chamber 58 Substrate 60 Discharge chamber 62 Discharge valve 64 Discharge hole 66 Valve port 67 Discharge valve element 68 Valve element part 70 Slider 72 Radiant fin 74 Flow path 76 Spring retainer 77 Projecting end face 78 Valve spring

Claims (4)

A movable and fixed scroll which are arranged so as to mesh with each other to form a compression chamber in the casing, and which cooperate with each other to suck the working gas into the compression chamber and compress the working gas in the compression chamber;
A scroll valve provided in the casing, comprising: a discharge valve configured to discharge the compressed working gas from the compression chamber to a discharge chamber adjacent to the fixed scroll in the casing.
The discharge valve,
A discharge hole having a valve port opened in the compression chamber, provided in the substrate of the fixed scroll for partitioning between the compression chamber and the discharge chamber, through the center of the substrate;
A valve body that is slidably inserted into the discharge hole in an axial direction of the discharge hole and that fits into the valve port at a closed position to close an opening surface of the valve port; A discharge valve body having a flow path connecting the valve port and the discharge chamber,
A scroll spring disposed between the discharge valve body and the inner wall surface of the casing in the discharge chamber, the valve spring pressing and biasing the discharge valve body toward the closed position. machine. The discharge valve further includes a spring retainer integrally projecting from the inner wall surface of the casing toward the substrate of the fixed scroll, and having a spring accommodating chamber opened at the projecting end surface therein.
2. The scroll-type fluid machine according to claim 1, wherein the valve spring presses and urges the discharge valve body while being housed in the spring housing chamber. 3. The method according to claim 2, wherein the projecting end surface of the spring retainer is arranged at a predetermined distance from the substrate, and an inner diameter of the spring accommodating chamber is smaller than an outer diameter of the discharge valve body. The scroll-type fluid machine according to any one of the preceding claims. The discharge valve body has a plurality of radiating fins provided on an outer peripheral surface thereof at intervals in a circumferential direction, and the flow path is formed between adjacent radiating fins. Item 2. A scroll type fluid machine according to Item 1.

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