Patent Publication Number: US-2005135941-A1

Title: Hermetic compressor

Description:
CROSS-REFERENCE TO RELATED APPLICATION  
      This application claims the benefit of Korean Patent Application No. 2003-95014, filed Dec. 22, 2003 in the Korean Intellectual Property Office, the disclosure of which is incorporated herein by reference.  
     BACKGROUND OF THE INVENTION  
      1. Field of the Invention  
      The present invention relates, in general, to hermetic compressors and, more particularly, to a hermetic compressor having an exhaust muffler and an exhaust pipe, coupled to the exhaust muffler, to exhaust a compressed refrigerant to an outside of the exhaust muffler.  
      2. Description of the Related Art  
      Generally, a hermetic compressor is a machine that draws and compresses a refrigerant in a hermetic casing, prior to discharging the compressed refrigerant to an outside of the hermetic casing. The hermetic compressor includes a compressing unit to compress the refrigerant, and a drive unit to drive the compressing unit.  
      The compressing unit is provided on a lower portion of the hermetic casing, and includes a cylinder block, a piston, and a cylinder head. The cylinder block defines a compression chamber. A drive power of the drive unit is transmitted to the piston, thus reciprocating the piston in the compression chamber. The cylinder head is mounted to an end of the cylinder block, and has a suction chamber and an exhaust chamber which communicate with the outside of the hermetic casing.  
      A valve plate is provided at a junction between the cylinder block and the cylinder head, with an inlet port and an outlet port being respectively provided on predetermined portions of the valve plate to allow the suction chamber and the exhaust chamber to communicate with the compression chamber. An intake valve and a discharge valve are mounted to the inlet port and the outlet port, respectively, to control a flow of the refrigerant.  
      Further, an exhaust muffler is provided at each of opposite ends of the cylinder block to reduce noise generated when the refrigerant is discharged from the hermetic casing. Meanwhile, the refrigerant compressed in the compression chamber sequentially passes through the discharge valve of the valve plate, the exhaust chamber of the cylinder head, and the exhaust muffler. Thereafter, the refrigerant is discharged to an outside of the compressor through the exhaust pipe coupled to the exhaust muffler.  
      In a conventional hermetic compressor, in order to couple the exhaust pipe to the exhaust muffler, a stepped depression is provided on a predetermined portion of the exhaust muffler, and a sleeve having a shape to correspond to the stepped depression is press-fitted into the stepped depression. Thereafter, the exhaust pipe is inserted into a hollow part of the sleeve, and then the sleeve is compressed using a caulking jig to prevent the exhaust pipe from being removed from the sleeve.  
      However, the conventional hermetic compressor has a problem in that the sleeve must be used to couple the exhaust pipe to the exhaust muffler, thus causing an increase in manufacturing costs of the hermetic compressor.  
      The conventional hermetic compressor has another problem in that the sleeve and the stepped depression which have complicated shapes are individually provided, so that it is difficult to manufacture the hermetic compressor, and productivity of the hermetic compressor is reduced.  
     SUMMARY OF THE INVENTION  
      Accordingly, it is an aspect of the present invention to provide a hermetic compressor which is capable of easily and firmly coupling an exhaust pipe to an exhaust muffler.  
      Additional aspects and/or advantages of the invention will be set forth in part in the description which follows and, in part, will be obvious from the description, or may be learned by practice of the invention.  
      The above and/or other aspects are achieved by a hermetic compressor, including a compression chamber, an exhaust muffler to reduce pulsations of a refrigerant compressed in the compression chamber, an exhaust port provided at a predetermined portion of the exhaust muffler to exhaust the refrigerant from an inside of the exhaust muffler to an outside of the exhaust muffler, and an exhaust pipe inserted into the exhaust port. The exhaust pipe includes a support part to support the exhaust pipe on an outer surface of the exhaust muffler, and a flare part provided at an inside end of the exhaust pipe to support the exhaust pipe on an inner surface of the exhaust muffler. The flare part is flared in a radial direction thereof.  
      According to an aspect of the invention, the inside end of the exhaust pipe may be flared by a caulking jig, with an end of the caulking jig facing the inside end of the exhaust pipe being gradually decreased in a diameter toward the exhaust pipe.  
      In another aspect of this embodiment, the support part may outwardly extend from the exhaust pipe in a radial direction of the exhaust pipe.  
      In yet another aspect of this embodiment, the exhaust muffler may include a depressed seat which is provided on the outer surface of the exhaust muffler at a portion around the exhaust port, with a washer being provided in the depressed seat to airtightly seal a gap between the exhaust pipe and the exhaust muffler. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
      These and other aspects and advantages of the invention will become apparent and more readily appreciated from the following description of the preferred embodiments, taken in conjunction with the accompanying drawings of which:  
       FIG. 1  is a side sectional view of a hermetic compressor, according to an embodiment of the present invention;  
       FIG. 2  is a plan view of the hermetic compressor of  FIG. 1 ;  
       FIG. 3  is a sectional view to show an exhaust pipe and an exhaust muffler included in the hermetic compressor of  FIG. 1 , in which the exhaust pipe is coupled to the exhaust muffler; and  
       FIGS. 4 and 5  are sectional views to show processes of coupling the exhaust pipe to the exhaust muffler of  FIG. 3 .  
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS  
      Reference will now be made in detail to the present preferred embodiments of the present invention, examples of which are illustrated in the accompanying drawings, wherein like reference numerals refer to like elements throughout. The embodiment is described below in order to explain the present invention by referring to the figures.  
       FIG. 1  is a sectional view to show a construction of a hermetic compressor, according to an embodiment of the present invention.  
      Referring to  FIG. 1 , the hermetic compressor includes a hermetic casing  10 . A compressing unit  20  and a drive unit  40  are housed in the hermetic casing  10 . The compressing unit  20  functions to compress a refrigerant. The drive unit  40  generates a drive power to drive the compressing unit  20 .  
      The compressing unit  20  includes a cylinder block  30  which defines a compression chamber  31  therein, and a piston  21  which reciprocates in the compression chamber  31  to draw, compress, and discharge the refrigerant. A cylinder head  22  is mounted to an end of the cylinder block  30 , with a suction chamber  22   a  and an exhaust chamber  22   b  being provided on the cylinder head  22 . A valve plate  23  is interposed between the cylinder block  30  and the cylinder head  22 . The valve plate  23  includes an intake valve  23   a  to allow the refrigerant to be drawn into the compression chamber  31 , and a discharge valve  23   b  to allow the refrigerant to be discharged from the compression chamber  31 .  
      The drive unit  40  is provided to reciprocate the piston  21 , thus compressing the refrigerant in the compressing unit  20 . The drive unit  40  includes a rotating shaft  42  which is rotatably installed at a frame  41 , and a rotor  43  which operates in conjunction with the rotating shaft  42 . The rotor  43  is spaced apart from a stator  44  by a predetermined distance and rotated by an electromagnetic field generated along the stator  44  when an electric power is applied to the stator  44 . Further, a connecting rod  45  is provided above the rotating shaft  42 . The connecting rod  45  is rotatably connected at a first end thereof to the rotating shaft  42 , and at a second end thereof to the piston  21  to rectilinearly reciprocate the piston  21 .  
      As shown in  FIG. 2 , an exhaust muffler  32  is provided on at least one end of opposite ends of the cylinder block  30  to reduce pulsations when the refrigerant is discharged to an outside of the compressor.  
      The exhaust muffler  32  defines a space therein, and communicates with the compression chamber  31  by means of a guide passage  33 . In this case, the guide passage  33  is provided in the cylinder block  30  to be spaced apart from the compression chamber  31 . A first end of the guide passage  33  is opened toward the cylinder head  22 , and a second end of the guide passage  33  forms a suction port  32   a  which communicates with the exhaust muffler  32 .  
      Further, an exhaust port  32   b  is provided on a predetermined portion of the exhaust muffler  32  to exhaust the refrigerant from the compression chamber  31 . An exhaust pipe  50  is coupled to the exhaust port  32   b , and guides the refrigerant to the outside of the compressor.  
      Referring to  FIG. 3 , the exhaust pipe  50  is inserted into the exhaust port  32   b  provided on the exhaust muffler  32 .  
      The exhaust pipe  50  includes a support part  51  and a flare part  52 . In this case, the support part  51  supports the exhaust pipe  50  on an outer surface of the exhaust muffler  32 , and the flare part  52  supports the exhaust pipe  50  on an inner surface of the exhaust muffler  32 . Further, the support part  51  outwardly extends from the exhaust pipe  50  in a radial direction of the exhaust pipe  50 . An inside end of the exhaust pipe  50  is flared in a radial direction of the exhaust pipe  50 , thus forming the flare part  52 .  
      Both the support part  51  and the flare part  52  allow the exhaust pipe  50  to be firmly coupled to the exhaust port  32   b  of the exhaust muffler  32 .  
      Further, a washer  60  is interposed between the support part  51  of the exhaust pipe  50  and an outer surface of the exhaust muffler  32  so as to airtightly seal a gap therebetween. A depressed seat  32   c  is provided on the outer surface of the exhaust muffler  32  at a portion around the exhaust port  32   b  so that the washer  60  is seated in the depressed seat  32   c.    
      The process of coupling the exhaust pipe  50  to the exhaust muffler  32  included in the hermetic compressor according to the present invention will be described in the following.  
      As shown in  FIG. 4 , the washer  60  is seated in the depressed seat  32   c  provided on the outer surface of the exhaust muffler  32 , and the exhaust pipe  50  is inserted into the exhaust port  32   b.    
      The exhaust pipe  50  includes the support part  51  which outwardly extends from the exhaust pipe  50  in the radial direction thereof. In this case, the exhaust pipe  50  having a shape of a general pipe is compressed from opposite ends of the exhaust pipe  50  toward an intermediate position of the exhaust pipe  50 , thus forming the support part  51 .  
      After the exhaust pipe  50  is completely inserted into the exhaust port  32   b  so that the support part  51  is supported on the outer surface of the exhaust muffler  32 , as shown in  FIG. 5 , the inside end of the exhaust pipe  50  is flared by a caulking jig  80  while an outside part of the exhaust pipe  50  outside the support part  51  is held by a holding jig  70 . In this case, the caulking jig  80  has a press part  81  at an end of the caulking jig  80  facing the inside end of the exhaust pipe  50 . A diameter of the press part  81  is gradually decreased toward the exhaust pipe  50 .  
      In a detailed description, as the press part  81  of the caulking jig  80  presses the inside end of the exhaust pipe  50 , the inside end of the exhaust pipe  50  forms the flare part  52 , as shown in  FIG. 3 , so that the flare part  52  supports the exhaust pipe  50  on the inner surface of the exhaust muffler  32 .  
      This invention has been described herein with reference to a case where the exhaust pipe  50  is mounted to the exhaust muffler  32  provided on the cylinder block  30 . But, the exhaust pipe  50  may be directly mounted to the hermetic casing  10 . In this case, the exhaust pipe  50  is mounted to the hermetic casing  10  in a same manner of coupling the exhaust pipe  50  to the exhaust muffler  32 .  
      As is apparent from the above description, the present invention provides a hermetic compressor, which is constructed so that a support part of an exhaust pipe supports the exhaust pipe on an outer surface of an exhaust muffler and a flare part of the exhaust pipe supports the exhaust pipe on an inner surface of the exhaust muffler, thus allowing the exhaust pipe to be firmly coupled to the exhaust muffler.  
      In the hermetic compressor of the present invention, the exhaust pipe is provided with a support part and a flare part so that the exhaust pipe is directly coupled to the exhaust muffler without any additional parts, such as a sleeve, differently from a conventional method where an exhaust pipe is coupled to an exhaust muffler using the sleeve. Thus, manufacturing costs of the hermetic compressor are reduced and a smaller number of parts are required, thus simplifying a working process and thereby enhancing productivity of the hermetic compressor.  
      Although an embodiment of the present invention has been shown and described, it would be appreciated by those skilled in the art that changes may be made in these embodiments without departing from the principles and spirit of the invention, the scope of which is defined in the claims and their equivalents.