Suction muffler for a hermetic compressor

Information

  • Patent Grant
  • 6688856
  • Patent Number
    6,688,856
  • Date Filed
    Monday, February 4, 2002
    22 years ago
  • Date Issued
    Tuesday, February 10, 2004
    20 years ago
Abstract
A closed motor-driven compressor includes a compression component (2) and an electric component (3) for driving the compression component (2), both of which are elastically supported within a closed vessel (1). A suction muffler (8) is mounted on the compression component (2) and includes a plurality of elements (10, 11, 12; 14, 15, 16; 18, 19, 20; 22, 23, 24; 26, 27, 28) assembled together and each made of synthetic resin. One of the plurality of elements (10, 11, 12; 14, 15, 16; 18, 19, 20; 22, 23, 24; 26, 27, 28) has a guide rib (13; 17; 21) integrally formed therewith that is tapered down toward an adjoining one of the plurality of elements (10, 11, 12; 14, 15, 16; 18, 19, 20; 22, 23, 24; 26, 27, 28), thereby facilitating assembly of the two elements.
Description




TECHNICAL FIELD




The present invention relates to a closed motor-driven compressor for use in refrigerators, air conditioners or the like.




BACKGROUND ART




Recently, closed motor-driven compressors are demanded to have a high energy efficiency, and it is well known that a suction muffler having a low thermal conductivity and made of, for example, synthetic resin is suited for use in such compressors.




Japanese Laid-Open Patent Publication (unexamined) No. 10-47248 discloses a closed motor-driven compressor as shown in

FIGS. 11 and 12

. This compressor includes a compression component


2


and an electric component


3


, both elastically supported within a closed vessel


1


. The compression component


2


includes a cylinder


4


, a piston


5


reciprocatingly accommodated in the cylinder


4


, a valve plate


6


mounted on the cylinder


4


so as to cover an opening defined therein, and a cylinder head


7


secured to the cylinder


4


. A suction muffler


8


′ made of synthetic resin and made up of three elements is mounted on the cylinder head


7


for introducing a refrigerant gas into the cylinder


4


. The suction muffler


8


′ is connected to a suction pipe


9


extending through a side wall of the closed vessel


1


to introduce the refrigerant gas into the closed vessel


1


.




As shown in

FIG. 13

, the muffler


8


′ includes a first element


29


, a second element


30


to which the first element


29


is secured, and a third element


31


secured to the second element


30


. As shown in

FIG. 14

, the first element


29


has an inwardly protruding guide rib


32


integrally formed therewith. The guide rib


32


acts to facilitate the assembling of the first and second elements


29


,


30


. After the first and second elements


29


,


30


have been assembled using the guide rib


32


, they are assembled with the third element


31


, and all of them are joined together by ultrasonic welding.




In the closed motor-driven compressor of the above-described construction, the refrigerant gas from the low-pressure side in a refrigerating cycle is introduced into the closed vessel


1


through the suction pipe


9


and then into the cylinder


4


through the suction muffler


8


′ before the refrigerant gas is compressed by the piston


5


.




In the above-described construction, however, because the suction muffler


8


′ is made of synthetic resin, it is apt to be deformed after injection molding. Accordingly, a difficulty is encountered in assembling the first and second elements


29


,


30


with the use of the guide rib


32


.




U.S. Pat. No. 5,341,654 discloses a refrigeration compressor, wherein V-shaped ribs extend laterally across respective flange portions as well as a tubular member adjacent the opposite ends of the flange portions of a muffler, which is fabricated from a polymeric composition.




The present invention has been developed to overcome the above-described disadvantages.




It is accordingly an objective of the present invention to provide a closed motor-driven compressor having an improved suction muffler that facilitates the assembly of its elements.




DISCLOSURE OF THE INVENTION




In accomplishing the above and other objectives, the closed motor-driven compressor according to the present invention includes a closed vessel, a compression component elastically supported within the closed vessel, an electric component elastically supported within the closed vessel for driving the compression component, and a suction muffler mounted on the compression component and including a plurality of elements assembled together and each made of synthetic resin. One (first element) of the plurality of elements has a guide rib integrally formed therewith that is tapered down toward an adjoining one (second element) of the plurality of elements. The tapered guide rib acts to reform deformation of the second element into which it is inserted, thus facilitating an assembly of the first and second elements.




The guide rib is formed discontinuously or intermittently along a peripheral edge of the first element. By so doing, strains caused by the cooling of the first element after injection molding are relatively small, thus reducing deformation of the first element.




The first element may have first and second peripheral portions and third and fourth peripheral portions each interposed between the first and second peripheral portions, wherein the first and second peripheral portions have first and second radii of curvature, respectively, while the third and fourth peripheral portions have third and fourth radii of curvature, respectively, that are smaller than the first and second radii of curvature, and wherein the guide rib is formed at the third or fourth peripheral portion and at the first and second peripheral portions adjacent thereto.




In assembling the first and second elements, the first and second portions of the second element having large radii of curvature are subjected to relatively small deformation, while the third and fourth portions of the second element having small radii of curvature are subjected to larger deformation. Accordingly, the guide rib formed at the first and second peripheral portions of the first element can be readily inserted into the corresponding portions of the second element, and the guide rib gradually reforms the deformation of the second element. Such insertion facilitates subsequent insertion of the guide rib into the third and fourth portions of the second element, making it possible to realize automated assembling of suction mufflers.




The plurality of elements are secured to one another by welding. The welding reduces a leakage of suction gas from the suction muffler.




Alternatively, the plurality of elements are secured to one another by fastening means such, for example, as rivets, screws, or the like. The use of such fastening means requires no expensive welding machine or the like.




Again alternatively, the plurality of elements are secured to one another by introducing projections formed therewith into openings defined therein. The assembling of the elements by engagement of the projections with the openings requires no fastening means referred to above.











BRIEF DESCRIPTION OF THE DRAWINGS




The above and other objectives and features of the present invention will become more apparent from the following description of preferred embodiments thereof with reference to the accompanying drawings, throughout which like parts are designated by like reference numerals, and wherein:





FIG. 1

is a top plan view of a closed motor-driven compressor according to the present invention with a closed vessel partially removed;





FIG. 2

is a vertical sectional view of the closed motor-driven compressor of

FIG. 1

;





FIG. 3

is an exploded view of a suction muffler mounted in the closed motor-driven compressor of

FIG. 1

;





FIG. 4

is an enlarged cross-sectional view of a portion A in

FIG. 3

;





FIG. 5

is a view similar to

FIG. 3

, but depicting a modification thereof;





FIG. 6

is a view similar to

FIG. 3

, but depicting another modification thereof;





FIG. 7

is a front view of one of a plurality of elements constituting the suction muffler of

FIG. 6

;





FIG. 8

is a bottom plan view of the element of

FIG. 7

;





FIG. 9

is a view similar to

FIG. 3

, but depicting a further modification thereof;





FIG. 10

is a view similar to

FIG. 3

, but depicting a still further modification thereof;





FIG. 11

is a top plan view of a conventional closed motor-driven compressor with a closed vessel partially removed;





FIG. 12

is a vertical sectional view of the closed motor-driven compressor of

FIG. 11

;





FIG. 13

is an exploded view of a suction muffler mounted in the closed motor-driven compressor of

FIG. 11

; and





FIG. 14

is an enlarged cross-sectional view of a portion A in FIG.


13


.











DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS




This application is based on application No. 11-147955 filed May 27, 1999 in Japan, the content of which is incorporated hereinto by reference.




Referring now to the drawings, there is shown in

FIGS. 1 and 2

a closed motor-driven compressor embodying the present invention. The compressor shown therein includes a compression component


2


and an electric component


3


for driving the compression component


2


, both of which are elastically supported within a closed vessel


1


. The compression component


2


includes a cylinder


4


, a piston


5


reciprocatingly accommodated in the cylinder


4


, a valve plate


6


mounted on the cylinder


4


so as to cover an opening defined therein, and a cylinder head


7


secured to the cylinder


4


. A suction muffler


8


is mounted on the cylinder head


7


for introducing a refrigerant gas into the cylinder


4


. The suction muffler


8


is made of synthetic resin and includes three elements assembled together. The suction muffler


8


is connected to a suction pipe


9


extending through a side wall of the closed vessel


1


to introduce the refrigerant gas into the closed vessel


1


.




As shown in

FIG. 3

, the suction muffler


8


includes a first element


10


, a second element


11


to which the first element


10


is secured, for example, by welding, and a third element


12


secured to the second element


11


, for example, by welding. The welding reduces a leakage of suction gas from the suction muffler


8


. Each of the first to third elements


10


,


11


,


12


is injection-molded from polybutylene terephthalate (PBT).




As shown in

FIG. 4

, the first element


10


has an inwardly or downwardly protruding guide rib


13


integrally formed therewith. The guide rib


13


is formed continuously along the peripheral edge of the first element


10


and is tapered down inwardly or downwardly. More specifically, the inner surface of the guide rib


13


extends substantially straight in the vertical direction, while the outer surface of the guide rib


13


is inclined such that the thickness of the guide rib


13


gradually decreases inwardly or downwardly.




By the above-described construction, in assembling the first and second elements


10


,


11


, the guide rib


13


of the first element


10


reforms deformation of the second element


11


. Accordingly, the first and second elements


10


,


11


can be assembled together merely by inserting the guide rib


13


into an associated end portion of the second element


11


, thus facilitating the assembling work.





FIG. 5

depicts a modification


8


A of the suction muffler


8


shown in FIG.


3


.




This suction muffler


8


A includes first to third elements


14


,


15


,


16


assembled together, just like the suction muffler


8


. The suction muffler


8


A, however, differs from the suction muffler


8


in that the first element


14


has an inwardly or downwardly protruding guide rib


17


that is formed discontinuously along the peripheral edge of the first element


14


.




Because the tapered guide rib


17


is formed intermittently along the peripheral edge of the first element


14


, strains caused by the cooling of the first element


14


after the injection molding are relatively small, thus reducing deformation of the first element


14


.





FIG. 6

depicts another modification


8


B of the suction muffler


8


, and as shown therein, the suction muffler


8


B includes first to third elements


18


,


19


,


20


assembled together.




The second element


19


has a generally crescent-shaped open end portion (upper end portion in this case), which has first and second portions opposite to each other and third and fourth portions opposite to each other and each interposed between the first and second portions. The first and second portions have respective relatively large radii of curvature, while the third and fourth portions have respective relatively small radii of curvature.




As shown in

FIGS. 7 and 8

, the first element


18


has a shape corresponding to that of the generally crescent-shaped open end portion of the second element


19


and, hence, has first and second peripheral portions having respective large radii of curvature and third and fourth peripheral portions having respective small radii of curvature and each interposed between the first and second peripheral portions. The first element


18


also has inwardly or downwardly protruding tapered guide ribs


21


each integrally formed therewith at the third or fourth peripheral portion and at the first and second peripheral portions adjacent thereto.




In assembling the first and second elements


18


,


19


, the first and second portions of the second element


19


having the large radii of curvature are subjected to relatively small deformation, while the third and fourth portions of the second element


19


having the small radii of curvature are subjected to larger deformation. Accordingly, the guide ribs


21


formed at the first and second peripheral portions of the first element


18


can be readily inserted into the corresponding portions of the second element


19


, and the former gradually reform the deformation of the second element


19


. Such insertion facilitates subsequent insertion of the guide ribs


21


into the third and fourth portions of the second element


19


, making it possible to realize automated assembling of suction mufflers.




As is the case with the suction muffler


8


A shown in

FIG. 5

, the first element


18


has separated or discontinuous guide ribs


21


and, hence, strains caused by the cooling of the first element


18


after the injection molding are relatively small, thus reducing deformation of the first element


18


.




As shown in

FIG. 9

depicting a further modification


8


C of the suction muffler, first to third elements


22


,


23


,


24


may have respective tabs


22




a


,


23




a


,


24




a


integrally formed therewith and extending laterally outwardly therefrom so that the three elements


22


,


23


,


24


may be assembled together by means of rivets


25


. The assembling of the elements


22


,


23


,


24


by the rivets


25


requires no expensive welding machine or the like. Screws may be used in place of the rivets


25


.




Alternatively, as shown in

FIG. 10

depicting a still further modification


8


D of the suction muffler, first to third elements


26


,


27


,


28


may have respective tabs and/or projections integrally formed therewith. In the case of

FIG. 10

, the first element


26


has downwardly extending tabs


29


each having an opening defined therein, while the second element


27


has projections


31


each formed at an upper portion thereof. Likewise, the second element


27


has downwardly extending tabs


30


each having an opening defined therein, while the third element


28


has projections


32


each formed at an upper portion thereof.




In assembling the three elements


26


,


27


,


28


, each of the projections


31


of the second element


27


is introduced into and received in the opening of the associated tab


29


of the first element


26


, while each of the projections


32


of the third element


28


is introduced into and received in the opening of the associated tab


30


of the second element


27


. The assembling of the elements


26


,


27


,


28


by the engagement of the projections


31


,


32


with the tabs


29


,


30


requires no additional fastening means such, for example, as screws, rivets, or the like.



Claims
  • 1. A closed motor-driven compressor comprising:a closed vessel; a compression component elastically supported within the closed vessel; an electric component elastically supported within the closed vessel for driving the compression component; and a suction muffler mounted on the compression component and comprising a plurality of elements assembled together and each made of synthetic resin, one first of the plurality of elements having a guide rib integrally formed therewith that is tapered down toward an adjoining one second of the plurality of elements, thereby facilitating assembly of the two elements, wherein the guide rib is formed discontinuously alone a peripheral edge of the first element, and wherein the one first element has first and second peripheral portions and third and fourth peripheral portions each interposed between the first and second peripheral portions, the first and second peripheral portions having first and second radii of curvature, respectively, the third and fourth peripheral portions having third and fourth radii of curvature, respectively, that are smaller than the first and second radii of curvature, and wherein the guide rib is formed at the third or fourth peripheral portion and at the first and second peripheral portions adjacent thereto.
  • 2. The closed motor-driven compressor according to claim 1, wherein the plurality of elements are secured to one another by welding.
  • 3. The closed motor-driven compressor according to claim 1, wherein the plurality of elements are secured to one another by fastening elements.
  • 4. The closed motor-driven compressor according to claim 1, wherein the plurality of elements are secured to one another by introducing projections formed therewith into openings defined therein.
Priority Claims (1)
Number Date Country Kind
11-147955 May 1999 JP
PCT Information
Filing Document Filing Date Country Kind
PCT/JP00/03124 WO 00
Publishing Document Publishing Date Country Kind
WO00/73656 12/7/2000 WO A
US Referenced Citations (9)
Number Name Date Kind
4531894 Kawai et al. Jul 1985 A
4573880 Hirano et al. Mar 1986 A
4759693 Outzen Jul 1988 A
5201640 Heinzelmann et al. Apr 1993 A
5341654 Hewette et al. Aug 1994 A
5588810 DiFlora et al. Dec 1996 A
5749714 Lee May 1998 A
6358019 Iversen et al. Mar 2002 B1
6394226 Cavicchioli May 2002 B1
Foreign Referenced Citations (3)
Number Date Country
0 073 469 Mar 1983 EP
0 902 184 Mar 1999 EP
59-43917 Mar 1984 JP