JPH01163401A - Scroll type machine - Google Patents

Abstract

PURPOSE: To reduce noise during the operation of a machine and reduce abrasion of wraps by forming a ground surface on a circumferentially outer end of a scroll wrap. CONSTITUTION: An orbiting scroll wrap 24 has an outer portion of its radially outwardly facing surface adjacent its radially outer free end 36 cut away or ground to define an ground offset surface 50 starting at a point 'A' at the free end of the wrap and extending to a point 'B', and then a ramp surface 52 tapering at a constant rate radially outwardly from the point 'B' to a point 'C' whereupon the wrap surface assumes its normal involute shape. Similarly, non-orbiting scroll wrap 30 has a ground offset surface 60 between points 'E' and 'F' and a ramp surface 62 tapering at a constant rate radially outwardly from the point 'F' to a point 'G' whereupon the wrap 30 is back to its original profile and thickness. Therefore, the sudden state fluctuation can be relaxed by several clearances formed between two scroll wraps 24, 30 by the offset surfaces 50 and 60, thus suppressing the generation of noises.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention This invention relates to scroll machines, and more particularly to scroll vane shapes that reduce noise and wear of the scroll vanes during machine operation.

[Conventional technology and its problems]

Scroll machines generally include a pair of first and second scroll members, each scroll member having an end plate and a helical scroll rising from the end plate. The scroll blades of both scroll members are fitted together and engaged in substantially line contact at a plurality of locations, and move as they are driven to rotate relative to the other scroll member. A plurality of fluid buckets l-i of variable volume are formed. Scroll machines can be implemented as bonders, compressors or fluid expanders.

It has been discovered that some scroll machines generate undesirable noise during operation. Investigating the cause of this noise, it was found that during machine construction, the outer free ends of one or both of the helical scroll blades may be bent slightly radially outward due to machining forces. I found out.

Its free end springs back into place after machining and is slightly misaligned, resulting in an undesirable engagement between the scroll blades during their relative pivoting motion. form a protrusion. Conversely, when machining the scroll 'R into a solid surface without a free end on the blade, the blade may not flex, but the tool may flex, producing a similar result.

Not only does such engagement result in heavy hitters, but it also causes wear on the scroll assembly, thereby placing additional loads on the crankshaft. Even if there is no bending or distortion of the blade tip, it is recognized that with a conventional scroll blade shape, there is a region in the scroll blade that is relatively likely to generate noise. Noise is also generated due to sudden dynamic changes that occur during machine operation at the point where the inner end of the scroll vane begins to communicate with the fluid discharge port and at the point where both scroll vanes separate from each other.

[Invention problem]

It is therefore a principal object of the present invention to provide a scroll machine which solves the above-mentioned noise and wear problems by a simple, economical construction and which does not substantially reduce efficiency.

[Problem solving means °]

In order to solve the above-mentioned problems, the present invention provides an outer surface of a helical scroll blade of at least one of both scroll members, from a point of the circumferential outer end that overlaps with the other scroll blade in the circumferential direction. A grinding surface is provided which is ground to reduce the blade thickness in an angular range extending inwardly. In the case of a conventional scroll blade, the ground surface metal as described above is provided at the outer end in the circumferential direction of the blade side surface, which forms a groove in the surface portion of the effective blade side surface.

The invention also proposes to provide a grinding surface similar to that described above on the inner surface of at least one scroll wing near the inner circumferential end of the scroll wing.

[Action and effect]

By providing the above-mentioned ground surface on the outer circumferential end of the scroll blade, even if the machining is not very precise, undesirable bonding between the two scroll blades can occur in conventional machines. Noise and blade wear during machine operation are reduced. Since the circumferential outer end portion of the scroll blade is located in a low pressure region in a scroll type machine, and because the degree of grinding of the outer surface of the blade is only slightly, it is possible to prevent fluid leakage due to the provision of a ground surface. It is negligible and does not reduce the efficiency of this ninth machine.

The grinding surface can be easily formed by using the blade for machining the blade by slightly biasing it inward in the trap radial direction and performing true machining, unlike when machining the entire scroll blade in the conventional way. Since precision is not required as much as conventional ones, the manufacturing cost is low. According to the structure in which a ground surface is provided on the inner surface of the blade near the inner end in the circumferential direction of the scroll blade to reduce the blade thickness, During machine operation, a small amount of dirt is formed between the two scroll blades by cutting into the grinding surface near the point where the inner end of the scroll blade begins to communicate with the port in the center of the scroll and the point where both the scroll blades separate from each other. The gap alleviates sudden state fluctuations and suppresses noise generation.

〔Example〕

Although the principles of this invention are applicable to various types of scroll machines, for illustrative purposes only
A hermetic scroll compressor is equipped with a pair of fitted spiral blades in the shape of a circular expansion line, and one spiral blade is driven to rotate relative to the other spiral blade by a crankshaft. A scroll compressor particularly suitable for compressing refrigerant for air conditioning and refrigeration will embody this invention and will describe a 7'c embodiment. This type of scroll compressor is disclosed in the patent application filed in 1986-20 by the applicant.
It is disclosed in detail in No. 8061 (Japanese Unexamined Patent Publication No. 63-80088).

The illustrated scroll compressor according to the present invention includes a scroll assembly 12 for compressing gas, an electric motor (not shown), and a companion crankshaft arranged vertically. A crankshaft provided at one end of the crankbin 14 that drives the scroll assembly 12 via a drive bushing 15, a compressor body 16, and an outer shell 18 surrounding all of the above-mentioned mechanical elements. We are prepared. The scroll assembly 12 includes an end plate 2
2 and an orbiting scroll member 20 having a scroll blade 24 having a desired side surface shape (e.g. circular expanded line shape) rising from the end plate, and an end plate 28 and a scroll wing 24 rising from the end plate. A non-orbiting scroll member 26 having a scroll JIE 30 having a similar shape to that described above is provided. The compressor body 16 supports an end plate 22 of an orbiting scroll member 20 via a conventional thrust receiver surface 31. Scroll assembly 12! ! Also, non-orbiting scroll member 2
A central discharge port 32 is provided in the end plate 28 of the orbiting scroll member 2 and is similar in shape to the discharge port.
Concave groove 33 for fluid transfer provided in end plate 22 of 0
, and an inlet port region 34.

The effective blade surface ends of the scrolls g24 and 30 are arranged on the axes X and y, which are opposite to each other on the diameter line, and the scroll blades 2
The effective wing surface tip of No. 4 is indicated by reference numeral 36, and the effective wing surface end of scroll wing 30 is indicated by reference numeral 38, respectively. Although the entire suction passage is formed, that part does not engage with the orbiting scroll blade 24, so that part does not function as a scroll blade.) Non-orbiting scroll wing 3
The inner end of 0 is designated by the symbol 40 and is located at
The inner end of is designated by 42.

In order to solve the above problems of the invention, the desired effect can be obtained by grinding the outer surface of each scroll blade in a region where it engages with the outer end of the other scroll blade so as to reduce the thickness of the blade. I found out.

As shown, the orbiting scroll blade 24 has a cut or ground outer surface portion near the radially outer free end 36;
Approximately 180° to 190° starting from point A at the free end of the wing
The ground and offset surface 50 extends to point B (the point immediately after passing through the axis y). Next, from point B to point C, it moves outward in the radial direction at a constant rate (approximately 20°
), and the wing surface has a normal expanded line shape from point C. An imaginary line D (4th (2)) shows the expanded linear outer surface of the orbiting scroll blade 24 in the case where no grinding is performed and there is no grinding.

Similarly, the non-orbiting scroll blade 30 also has a distance of about 8° between point E and point 2.
Ground 9-sided surface 6
0, and approximately 20° radially outward from point F to point G.
The blade 30 is provided with a slope 62K inclined at a constant rate of 21° to 21°, and the point G is the point at which the blade 30 returns to its original shape and thickness. An imaginary line H (FIG. 3) shows the expanded linear outer surface of the non-orbiting scroll blade 30 in the case where no grinding is performed and the scroll blade 30 is not ground.

The ground nx surfaces 50 and 60 are ground by cutting the wing cutting tool very slightly radially inward (for example, with an overall outer diameter of approximately 85 mm) to create an offset surface parallel to the normal extended linear surface. A scroll equipped with a certain orbiting scroll IX (4 cods) can be easily formed by simply shifting. Such a surface 50.60
Fluid leakage based on
0.60 is extremely small because the pressure in the machine is relatively low.

It has been found that it is also effective to perform similar blade surface grinding near the inner end of the scroll blade. Therefore, the orbiting scroll blade 24 is formed to have a portion near the free end 42 on the radially inner side where the inner surface is cut or ground to completely eliminate the blade thickness. From point J to point K, the part has a whole grinding surface 64 that is sloped radially outward at a constant rate. Similarly, the non-orbiting scroll blade 30 also has a portion near the free end 40 on the radially inner side where the inner surface side is ground and the X thickness is reduced, and the radially outward direction from the point to the point M is constant. Grinding surface 66 inclined in proportion
is formed. Points J and L are the points where both the extended linear scroll blades, which have not undergone blade surface grinding, separate from each other υ
It is a point on the wing side surface located slightly outward in the radial direction, and it is a point where the discharge port 32 and the groove 33 are opened. The point M is located slightly inward in the radial direction from the point where the two conventional scroll blades in the form of an extended line, which are not subjected to grinding, are separated from each other.

In the figure, the slope 64.66 is large and exaggerated,
To smoothly transition a scroll blade tip from a loaded state to an unloaded state. Leakage due to the sloped area is not a problem since the discharge port 32 opens in the same area.

As described above, by completely modifying or remodeling the side shape of the scroll blade in the nine aspects described above, noise and wear are reduced, and the precision requirements of the manufacturing process are reduced, time is shortened, and economical efficiency is increased. It will be done.

[Brief explanation of the drawing]

FIG. 1 is a vertical sectional view showing a surface portion of a scroll assembly of a hermetic scroll compressor embodying the principles of the present invention. FIG. 2 is a skin-like sectional view taken along line 2-2 in FIG. 3 and 4 are enlarged views of the surface portion of FIG. 2, respectively, and show the outer ends of the functional parts of the scroll blades in an exaggerated and rounded shape. 12... Scroll assembly, 20... Orbiting scroll member, 22... End plate, 24... Scroll blade, 2
6... Non-orbiting scroll member, 28... End plate, 30
...Scroll wing, 32...Ejection port, 34...
- Suction port area, 36... Effective wing surface tip, 38...
Effective wing surface end, 40... Wing inner end, 42... Wing inner end, 5
0... Unbalanced surface, 52... Slope, 60... Unbiased surface,
62...Slope, 64...Grinded surface, 66...Grinded surface.

Claims (16)

[Claims] 1. a pair of scroll members each comprising an end plate and a helical scroll vane protruding from the end plate having an effective vane side surface and a radially inward tip; and a scroll member for receiving and discharging fluid. The scroll blades of both scroll members are fitted together such that the effective blade side surfaces thereof engage with each other at a plurality of spaced locations to form a plurality of fluid pockets. and when one scroll member is pivoted relative to the other scroll member, the fluid pocket is moved between the ports to receive fluid from one port and flow into the other port. In a scroll-type machine configured to discharge a fluid, in the outer surface of one of the scroll blades, from the point of the circumferential outer end of the outer surface on the other scroll blade. A scroll-type machine characterized by having a first grinding surface extending inward in the circumferential direction and offset from a surface that would function as an effective blade side surface if not ground. . 2. 2. The scroll-type machine according to claim 1, wherein the effective wing sides of both scroll wings have complementary contours, and the first grinding surface is offset radially inward from the contour. A scroll-type machine parallel to the contour. 3. 3. A scroll machine according to claim 2, wherein the contour is an expanded line of a geometric figure. 4. 4. A scroll machine according to claim 3, wherein the geometrical figure is a circle. 5. 3. Scroll machine according to claim 2, wherein the effective wing sides of both scroll wings have equal contours. 6. 2. The scroll type machine according to claim 1, wherein an inclined surface is provided between the circumferential inner end of the ground surface of the one scroll blade and the effective blade side surface of the one scroll blade. 7. 7. A scroll machine according to claim 6, wherein the slope is sloped radially outward at a constant rate. 8. 2. A scroll type machine according to claim 1, wherein both of the scroll blades are provided with the grinding surface. 9. 2. The scroll-type machine according to claim 1, wherein a second blade is provided on the inner surface of one of the scroll blades near the blade tip at a theoretical blade separation point on the contour of the effective blade side surface. A scroll-type machine with a grinding surface. 10. 10. The scroll machine of claim 9, wherein the second grinding surface has a surface portion extending radially outward from the inner blade surface. 11. The scroll machine according to claim 10,
A scroll type machine in which the surface portion is inclined radially outward at a constant rate. 12. The scroll machine according to claim 1, wherein an inner surface of one of the scroll blades is provided near the tip of the scroll blade so that the outer surface of the scroll blade is exposed to the fluid of the center port during operation of the scroll machine. A scroll-type machine having a second grinding surface at the point where pressure is first applied. 13. 2. A scroll machine as claimed in claim 1, in which the scroll machine is operated from a theoretical blade separation point at the contour of the effective blade side, inside one of the scroll blades near the blade tip. A scroll machine having a second grinding surface therein straddling the point at which the outer surface of the scroll vane first experiences fluid pressure in the center port. 14. The scroll type machine according to any one of claims 9, 12, and 13, wherein the second scroll blade is provided on both the scroll blades.
A scroll-type machine with a grinding surface. 15. 2. A scroll type machine according to claim 1, wherein said first grinding surface is provided over a range of 28 DEG to 30 DEG from said circumferential outer end point. 16. In the scroll type machine according to claim 15,
The first ground surface extends inward in the circumferential direction from the circumferential outer end point, and is straddled between the biased surface portion and the effective blade side surface. A scroll-type machine with a sloped section.