JPS61152985A - Scroll compressor device - Google Patents

Abstract

PURPOSE:To enable a scroll compressor to reduce its vibration and noise, by positioning the center of gravity of a movable scroll element on the basic circle center of an involute blade and the turning radius determining axial line of an eccentric joint mechanism. CONSTITUTION:A movable scroll element 22 in a scroll compressor comprises an involute-shaped blade member 34, protrusively provided on the surface of an end plate 33, and a boss part 35 protruded from the back surface of the end plate and fitting an eccentric joint mechanism. The center of gravity of the movable scroll element is enabled to change its position by cutting one part E of the end plate, but this scroll compressor sets the center of gravity of the movable scroll element so as to be aligned on the involute basic circle center of the blade member and the turning radius determining axial line T2 of the eccentric joint mechanism. In this way, the scroll compressor, decreasing a change of shaft torque driving the movable scroll element, enables a vibration and a noise to be reduced.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to an improvement of a scroll-type compression device in which a scroll-type compression mechanism is housed in a closed case.

[Technical Background of the Invention and Problems Therewith] A scroll type compression device has been known as a low-pressure compression device. This compression device has a compression mechanism constructed by concentrically interlocking a pair of scroll blades, and has advantages such as small size, efficiency, and low imaging speed.

By the way, such a scroll type compression device usually
A frame is fixed at a position slightly above the closed case in a manner that vertically partitions the inside of the closed case, a scroll type pressure m114M is arranged above the frame, and the scroll type compression mechanism is placed below the frame. A motor is installed to provide driving power, and lubricating oil is stored at the bottom of the sealed case. A scroll-type compression mechanism is usually composed of a fixed element having a scroll blade protruding from an end plate, and a movable element having a scroll blade protruding from the end plate, which is disposed below the fixed element and engages with the scroll blade. There is. Each scroll blade is formed in the shape of a blade formed by connecting semicircular arcs or in an involute shape. A bearing hole is provided vertically through the frame, and the rotating shaft of the motor described above is rotatably supported by the bearing hole. In addition, an eccentric coupling mechanism and an Oldham mechanism are provided between the upper end of the rotating shaft and the movable element and between the frame and the movable element, and the eccentric coupling mechanism consisting of the eccentric coupling mechanism and the Oldham mechanism allows the movable element to rotate on its own axis. I am trying to make an unaccompanied turning movement. In order to improve the pressure balance in each compression space during the compression operation, reduce torque fluctuations, and suppress vibrations as much as possible, the scroll blades are formed in the shape of a circular arc formed by connecting semicircular arcs. , so that the center line for determining the turning radius of the eccentric joint mechanism is aligned with the midpoint on the line connecting the radius center of the semicircular arc portion closest to the center of the movable element side scroll blade and the radius center of the next closest semicircular arc portion. I have to.

Similarly, when the scroll blade is formed in an involute blade shape, the center of the base circle of the scroll blade on the movable element side is made to coincide with the center line for determining the turning radius of the eccentric joint mechanism.

However, the conventional scroll type compression device configured as described above has the following problems. That is, if the settings are made as described above, the pressure can certainly be balanced.

However, since the center of gravity of the entire movable element does not coincide with the turning radius determining axis, torque fluctuations due to centrifugal force still remain, and vibrations and noise cannot be reduced to a significant extent. Therefore, in conventional devices, the end plate is formed thick in advance, and the back side of the end plate is gouged out to align the center of gravity of the entire movable element with the turning radius determining axis.

However, with such a structure, if the scroll blade is high, it is difficult to align the center of gravity unless the head plate is made sufficiently thick, and as a result, the entire movable element becomes large and heavy. There was a problem that the number of inputs increased.

[Object of the Invention] The present invention has been made in view of the above circumstances, and an object thereof is to increase the center of gravity of the entire movable element without increasing the size and weight of the movable element. It can be matched with the determined axis center line, which reduces vibration.
It is an object of the present invention to provide a highly reliable scroll type compression device that can effectively reduce noise and input power.

[Summary of the Invention] According to the present invention, each of the mirror plates is constructed by protruding scroll blades from the mirror plate, and the scroll blades are concentrically engaged and compressed between each other! A scroll-type compression mechanism consisting of a fixed element and a movable element constituting the is disposed in a sealed case, and the power of the motor provided in the sealed case is transmitted to the movable element via an eccentric joint mechanism. Gas compression is performed by making a circular motion without rotation, wherein the center of gravity of the entire movable element is connected by a notch in the peripheral edge of the end plate of the movable element, and the scroll blade connects a semicircular arc. If the scroll blade is formed into an involute blade shape, the scroll blade is located at the midpoint of a line connecting the radius center of the semicircular arc part closest to the center and the radius center of the next closest semicircular arc part, and the scroll blade is an involute blade. For those formed into a shape, place it at the center of the base circle,
Furthermore, there is provided a scroll-type compression device in which the center of gravity of the entire movable element is located on the pivot radius determining axis of the eccentric joint mechanism that determines the pivot radius of the movable element.

[Effects of the Invention] As described above, if the center of gravity of the entire movable element is aligned with the turning radius determining axis by cutting out the peripheral edge of the head plate, the head plate has the minimum necessary thickness for strength. It is sufficient to allow for the notch and to make the diameter of the notch slightly larger in advance. Therefore, unlike conventional devices, the center of gravity of the entire movable element can be aligned with the turning radius determining axis without increasing the size or weight of the auxiliary element. In addition, we cut out areas that are easy to precisely machine, such as the notches on the periphery of the end plate.
Accurate balance adjustment can be achieved. In this way, since the movable elements can be made lighter, input can be reduced. Moreover, since the center of gravity can be easily and accurately aligned, it is possible to achieve even lower imaging and noise reduction, and since there is no local stress concentration in the drive section,
It is possible to provide a highly reliable device that does not suffer from burn-in or damage.

[Embodiments of the invention] Embodiments of the present invention will be described below with reference to the drawings.

In FIG. 1, reference numeral 11 indicates a vertically long sealed case, and this sealed case 11 is a cylindrical intermediate case 1.
2, and closing cases 13a and 13b welded to close both ends of the intermediate case 12. A frame 14 is fixed at an odd upper position inside the sealed case 11 in a form that partitions the inside of the sealed case 11 in the vertical direction. A scroll-type compression mechanism 15 is disposed above the frame 14, and the scroll-type pressure ttmm mechanism 15 is driven below the frame 14. A motor 16 for providing power is disposed, and a lubricating oil 17 is housed in the bottom of the sealed case 11.

The scroll type compression mechanism 15 is composed of a fixed element 21 and a movable element 22 disposed below the fixed element 21, as in the known one.

The fixing element 21 includes a disk-shaped mirror plate 23, an annular wall 24 protruding from the peripheral edge of one side of the mirror plate 23, and a portion surrounded by the annular wall 24 having the above-mentioned annular shape. 24, a wing-shaped scroll blade 25 formed by connecting semicircular arcs, and a discharge port 2 provided approximately at the center of the mirror plate 23.
It consists of 6. The inner end edge of the annular W24 is a curved surface with an appropriate curvature or as shown in FIG. 2(a).
It is formed on a cutout surface 27 such as a tapered surface as shown in FIG. In the fixing element 21 configured as described above, the peripheral edge of the annular wall 24 is hermetically fixed to the upper peripheral edge of the frame 14 with bolts 28 with the protruding direction of the annular wall 24 and scroll 3125 facing downward. In addition,
At the time of fixing, a cap 29 is applied to the upper surface of the fixed length 121, and this cap 29 is also fixed integrally with the bolt 28. The cap 29 is sized to form a gap 30 of a predetermined thickness between the cap 29 and the upper surface of the end plate 23, and a hole 31 is formed in a part of the wall forming this gap 30. Further, a hole 32 for guiding lubricating oil, which will be described later, is formed in a part of the side wall.゛On the other hand, the movable element 22 includes a mirror plate 33 having an outer diameter slightly larger than the inner diameter of the annular wall 24, and a mirror plate 33 protrudingly provided on one surface of the mirror plate 33 at a height and shape approximately equal to the height of the scroll blades 25. Scroll! 134, and a cylindrical portion 35 protruding from the other center of the mirror plate 33 in the drawing. When the mirror plate 33 was first manufactured, it was formed into a complete circle including the two-dot chain line as shown in FIG. In order to align the center of gravity with point B shown in FIG. 5, which will be described later, a portion indicated by E in FIG. 3 is cut away. Here, the reason why the center of gravity of the entire movable element 22 is made to coincide with point B will be explained. That is, in the case of the scroll type compression mechanism 15, an even number of compression chambers is formed when the fixed scroll blades 25 and the movable scroll 1134 are engaged, but the point of application of the force generated by the differential pressure between these compression chambers is In the case of an airfoil shape in which semicircular arcs are connected, geometrically, the fixed side scroll I [
25, the center 02 of the next closest semicircular arc, the center 03 of the semicircular arc closest to the center of the movable scroll 1134, and the center 04 of the next closest semicircular It exists on the intersection Os of the diagonals. The direction is tangential and opposite to the rotating direction of the movable scroll [34]. The center of the trajectory of the above intersection 05 is
It exists at midpoint A on the line connecting center 01 and center 02.

Therefore, by aligning the center line for determining the turning radius of the movable element 22 with the midpoint of the line connecting centers 03 and 04, and making the turning center coincide with the midpoint A, torque fluctuations due to differential pressure in the compression chamber can be suppressed. This can be prevented. However, this alone cannot completely eliminate torque fluctuations. That is, the center of gravity of the entire movable element 22 also needs to coincide with the point. For this reason, in this embodiment, the center of gravity of the movable element 22 as a whole is aligned with point B by cutting out the portion of the end plate 33 indicated by E. Further, the cylindrical portion 35 is provided so that the axial center line T2 of the cylindrical portion 35, that is, the turning radius determining axis line passes through the point B. In the movable element 22 configured as described above, the scroll m34 and the scroll blade 25 are engaged with each other with the protruding direction of the scroll blade 34 being upward, and the peripheral part of the mirror plate 33 and the end face of the annular wall 24, The end face of the scroll blade 34 and the mirror plate 23 and the end face of the scroll blade 25 and the mirror plate 33 are mounted so as to be in sliding contact with each other, and this mounted state is maintained by an Oldham mechanism 40 provided between the mirror plate 33 and the frame 14. ing.

The Oldham mechanism 40 includes key grooves 41a and 41b provided at two locations on the same line drawn through the center of the end plate 33 at the lower peripheral edge of the end plate 33, and the key grooves 41a and
Key grooves 42a, 4 are provided on a line perpendicular to the arrangement direction of the elements 1b and on the upper surface of the frame 14 as shown in FIG.
2b, and the key groove 41 on one side as shown in FIG.
a.

The key 4 has keys 43a and 43b that fit into the key grooves 41b and has keys 43a and 43b that fit into the key grooves 42a and 42b on the other side.
4a and 44b.

On both sides of the ring 45, for example, mesh-like oil grooves 46 are actually formed to reduce sliding resistance, as shown in FIG. In addition, each of the key grooves 4
2a.

On the inner surfaces of 42b, 41a, 41b, key 1 is shown in FIG.
As represented by It42b, a wide-mouth stepped portion 47 is formed to reduce the sliding area with the key.

A bearing hole 51 is provided vertically through the frame 14 so that its axis T1 passes through the point A, and the portion of the bearing hole 51 located on the cylindrical portion 35 side has a large diameter. is formed. The frame structure on the larger diameter side is specifically constructed as shown in FIG. That is, an annular wall 52 is formed on the outermost side, which has an outer diameter approximately equal to the inner diameter of the sealed case 11 and has an inner diameter larger than the inner diameter of the annular wall 24, and the annular wall 24 is tightened and fixed by the bolt 28. The annular receiver that receives the ring 45 on the inner side is formed with a surface 55 lowered one step, and the annular receiver that is further lowered one step on the inside and receives the thrust force reduction mechanism 59 described later is formed with a surface 56. has been done. The large surface has grooves 57 provided radially.
At least one of the grooves 57 communicates with a hole 58 that is provided in the wall of the frame 14 and allows direct communication between the inside and outside. Note that the keyway 4
2a, 42b, the receiver is formed on the surface 55.

Specifically, the main parts of the thrust force reduction mechanism 59 are as follows:
As shown in FIGS. 9(a) and (b), the annular receiver is 56
an annular body 60 that is fitted and supported, an annular groove 61 carved on the upper surface of this annular body 60, an annular groove 62 that is shallower and narrower than the annular groove 61 formed on the inside and outside of this annular body 1161, respectively. 63, and members for minimizing thermal expansion, for example, an inner seal ring 64 and an outer seal ring 65 made of tetrafluoroethylene, which are installed in the annular grooves 62 and 63 so that a portion thereof projects outward, respectively. It consists of A tapered surface 66 is formed at the lower end of the outer circumferential surface of the seal ring 64, as shown in FIG. There is. Furthermore, bottomed holes 67 are formed at four positions in the annular groove 61 in the weekly direction to communicate the annular groove 61 with the annular grooves 62 and 63 at the same depth as the annular groove 61. The annular body 60, inner and outer seal rings 64 and 65, and the lower surface of the end plate 33 are installed inside the end plate 33 with the thrust force reduction mechanism 59 installed as shown in FIG. Holes 68, 69 are formed which allow the enclosed annular space Q to always communicate with the medium pressure boats s, s' of the compression chamber P.

A rotating shaft 70 of the motor 16 is rotatably supported in the bearing hole 51 of the frame 14 .

The rotating shaft 70 has a large diameter portion 71 formed in a portion located in the large diameter portion of the bearing hole 51, and a small shaft 72 that fits into the aforementioned cylindrical portion 35 is protruded from this large diameter portion 71. There is. The rotary ring 70 has a length such that its lower end penetrates into the lubricating oil 17, and its lower end is supported by a sub-bearing 74 fixed to the inner surface of the sealed case 11.

Inside the rotating shaft 70, there is a hole 9 through which the lubricating oil 17 is pumped up to the bearing surface and the fitting part between the small shaft 72 and the cylindrical part 35 by a centrifugal pump action.
0 is formed. The shape of the entrance portion of this hole 90, that is, the portion located at the lower end of the rotating shaft 70, includes a portion 91 extending upward from the center of the lower end surface of the rotating shaft 70, and a portion 92 extending radially from this portion 91. , this part 92
and a portion 93 extending vertically at the peripheral edge position within the rotating shaft 70 so as to intersect at right angles.

The motor 16 has a rotor 100 inside and a stator 10 inside.
1 is placed on the outside, and a stator 101 is fixed to the inner surface of an intermediate case 12.

Further, a portion of the side wall of the intermediate case 12 of the sealed case 11 located between the scroll type compression mechanism 15 and the motor 16 is connected to a space 110 between the scroll type compression mechanism 15 and the motor 16. In relation to the suction pipe 11
1 is connected to the wall of the closing case 13a, and a space 1 formed between this wall and the fixing element 21 is connected to the wall of the closing case 13a.
A discharge pipe 113 is connected in communication with 12.

Note that 114 in FIG. 1 indicates a hole provided in the annular wall 24 and the frame 14 in order to return the ff1FR oil pushed out into the space 112 below the frame 14;
5 indicates a balance weight, 116 indicates a connection mechanism for power supply to the motor 16, 117 indicates a hole for passing lubricating oil, and 118 indicates a reversal prevention mechanism.

Next, the operation of the compression device configured as described above will be explained.

First, when power is supplied to the motor 16, the rotating shaft 70 starts rotating. This rotation is smoothly maintained by both the bearing hole 51 and the auxiliary bearing 74. The rotational force of the rotating shaft 70 is then transmitted to the movable element 22. The cylindrical portion 35 of the movable element 22 has a small shaft 72 provided eccentrically with respect to the rotating shaft 70.
Since the movable element 22 is fitted with the movable element 22 and supported by the Oldham mechanism 40, the movable element 22 performs a turning movement without rotation. Therefore, the scroll 134 provided on the movable element 22 also performs a pivoting movement.

Along with this swirling movement, the volume of the compression chamber P formed between the scroll blade 25 and the scroll m34 is periodically reduced, and the compressed gas is thereby transferred to the discharge port 26.
It is discharged from. The discharged high pressure gas is sent out from the discharge pipe 113 through a gap 30 formed by the cap 29, a hole 31 provided in the cap 29, and a space 112.

On the other hand, when the movable element 22 pivots as described above, an opening is formed between the peripheral edge of the mirror plate 33 of the movable element 22 and the inner edge of the annular wall 24 of the fixed element 21, and the The receiver whose peripheral edge is formed on the frame 14 is always in communication with the space above the surface 55. The above space is
It communicates with the hole 58 through the groove 57 etc. provided radially in the frame 14, and this hole 58 also communicates with the suction pipe 111 through the space 110, so that the low pressure gas eventually flows through the suction pipe 111 to the suction pipe 111. The space 110 - the hole 58 - the receiver will be sucked into the low pressure port in the compression vP via the space on the surface 55, and here the function as a compression device is exhibited. Note that even if a liquid such as a refrigerant is mixed into the low-pressure gas that has flowed in through the suction pipe 111, this liquid will fall downward while moving within the space 110, and the liquid will fall to the bottom where the FTL crushed oil 17 is collected. Try to move to . Since the motor 16 generates heat by itself, the fallen liquid is gasified by the heat, mixes with the flow of the already gasified liquid, and moves into the compression chamber P. Therefore, the space 110 has exactly the same function as a gas-liquid separator.

On the other hand, when the motor 16 rotates as described above, the lubricating oil 1
7 is pumped upward into the hole 90 by the centrifugal pumping action associated with the shape of the hole 90. This pumped up lubricating oil lubricates the inner circumferential surface of the bearing hole 51, then lubricates the fitting part between the small shaft 72 and the cylindrical part 35, and then
The part where the Oldham mechanism 40 is installed is lubricated through the hole 58, and then part of it flows down from the hole 58, and the rest enters the compression chamber P and lubricates the sliding part in the compression chamber P. Lubricate. The lubricating oil that has entered the compression chamber P is finally discharged from the discharge 026, and then flows downward through the hole 32 and the hole 114 provided in the cap 29. Therefore, high pressure gas containing no lubricating oil is discharged from the discharge pipe 113.

Further, as described above, when the movable element 22 performs a rotational motion and a compression operation is performed, the pressure inside the compression chamber P becomes high, so the movable element 22 receives a downward thrust force, and this force is transferred to the Oldham mechanism. 40, the receiver of the frame 14 touches the surface 55, etc., and there is a possibility that a burn-in phenomenon may occur on these elements. However, in the case of this embodiment, the thrust force reduction mechanism 59 prevents the occurrence of the burn-in phenomenon in the following manner.

That is, the annular space Q surrounded by the annular pair 60 of the thrust force reduction mechanism 59, the seal rings 64, 65, and the end plate 33 is always connected to the so-called medium pressure boats s, s of the compression chamber P through the holes 68, 69. ' is familiar to me. Therefore, the end plate 33 receives an upward force due to the gas pressure in the annular space Q, and the presence of this force reduces the downward thrust force that the end plate 33 receives. This reduction prevents the burn-in phenomenon from occurring.

Furthermore, when the motor 16 is stopped, there is a risk that the movable element 22 will rotate in the opposite direction due to the pressure difference between the space 112 and the space 110, causing high pressure gas to flow into the low pressure side. However, in the case of this embodiment, since the reversal prevention mechanism 118 is provided, the occurrence of reverse rotation is reliably prevented and the outflow of high pressure gas is prevented.

By cutting out the peripheral edge of the end plate 33 of the movable element 22 in this way, the center of gravity of the entire movable element 22 can be aligned to a position where torque fluctuations due to differential pressure in the compression chamber can be prevented, and the center of gravity can be roughly adjusted. It is set so that the center line of the axis that determines the turning radius passes through. Therefore, the occurrence of torque fluctuation can be prevented without making the end plate 33 of the movable element 22 particularly thick. Therefore, it is possible to achieve low vibration and low noise while preventing the movable element 22 from increasing in size and weight, and also to reduce the input, so that the above-mentioned effects can be obtained.

Note that the present invention is not limited to the embodiments described above. That is, in the embodiment, the motor is arranged below the movable element, but the present invention is applicable to the motor arranged above the movable element, or the so-called motor which is used with the axis horizontally. Of course, it can also be applied to horizontal types. Furthermore, although the above-mentioned embodiment is an example in which the present invention is applied to a so-called low-pressure type where the pressure is low on the back side of the movable element, the present invention is also applicable to a so-called high-pressure type where the back side of the movable element is high pressure. can. In addition, if the scroll part of the movable element is formed in the shape of an involute blade, the peripheral edge of the end plate is cut out to align the center of gravity of the entire movable element with the center of the base circle of the involute, and the center of gravity It suffices if it coincides with the determined axis center line. Further, the seal ring of the thrust force reduction mechanism may be brought into pressure contact with the movable element using an elastic body such as a coil spring.

Further, the notch in the peripheral edge of the end plate of the movable element may be cut out so that the notch surface has a tapered shape. In addition, various changes can be made without changing the gist of the present invention.

[Brief explanation of drawings]

FIG. 1 is a vertical cross-sectional view of a scroll-type compression device according to an embodiment of the present invention, FIG. 2(a) is a bottom view of a fixing element in the same device, and FIG. 3 is a top view of the movable elements of the same device; FIG. 4 is a sectional view taken along line B-B in FIG. 3; and FIG. is a diagram for explaining how to determine the center of gravity of a movable element, and Figure 6 is a diagram for explaining how to determine the center of gravity of a movable element.
Fig. 7 is a partially cutaway exploded perspective view showing only the upper part of the device; Fig. 7 is a plan view of the main parts of the Oldham mechanism in the same device;
The figure is a diagram for explaining the shape of the keyway of the Oldham mechanism, Figure 9 (a) is a vertical cross-sectional view of the thrust force reduction mechanism incorporated in the same device, and Figure 9 (b) is a - A cutaway view taken along the line C, and FIG. 11... Sealed case, 14... Frame, 15...
・Scroll type compression mechanism, 16...Motor, 17...
- Lubricating oil, 21...fixed element, 22...movable element,
25° 34...Scroll blade, 26...Discharge port, 4
0...Oldham mechanism, 51...Bearing hole, 59...
Thrust force reduction mechanism, 60... Annular body, 61... Annular groove, 64... Inner seal ring, 65... Outer seal ring, 68. 69... Hole as communication path, 70
... Rotating shaft, 74 ... Sub bearing, 90 ... Hole for centrifugal pump, 100 ... Rotor, 101 ... Stator,
103... Reversal prevention mechanism, 110.112... Space, 111... Suction pipe, 113... Discharge pipe, P...
Compression chamber, Q... annular space. Figure 3 Straw 4 Work 5 Figure 11 & 7 Figure 8 Figure 9 (a) (b) (C); Continued from page 1) Inventor Hitoshi Hattori Shin-Sugita-cho Research Institute, Isogo-ku, Yokohama City

Claims (1)

[Claims] Each is composed of a mirror plate with scroll wings protruding from it,
A scroll-type compression mechanism consisting of a fixed element and a movable element that are concentrically engaged to form a compression chamber between them is arranged in a sealed case, and the power of the motor installed in the sealed case is transmitted through an eccentric joint. In the scroll type compression device, the gas is compressed by transmitting a signal to the movable element via a mechanism and causing the movable element to perform a rotational motion without rotation, a notch in the peripheral edge of the end plate of the movable element. The center of gravity of the entire movable element is determined by the radius center of the semicircular arc part closest to the center and the radius of the next nearest semicircular arc part if the scroll wing is formed in the shape of an arc wing made by connecting semicircular arcs. If the scroll blade is formed into an involute blade shape, the center of the base circle is located at the center of the base circle, and the center of gravity of the entire movable element is set at the center of the base circle, and the center of gravity of the entire movable element is A scroll type compression device, characterized in that the scroll type compression device is located on a turning radius determining axis of the eccentric joint mechanism that determines the radius.