Patent Publication Number: US-6336794-B1

Title: Rotary compressor assembly with improved vibration suppression

Description:
BACKGROUND OF THE INVENTION 
     1) Field of the Invention 
     The present invention relates to rotary compressor assemblies and, more particularly, to a rotary compressor assembly of the type including a supporting plate for supporting a rotary compressor on which an accumulator is mounted. 
     2) Description of Related Art 
     Generally speaking, a rotary compressor assembly is used to compress a refrigerant to high temperature and high pressure and to discharge the same, in a cooling cycle of an air conditioner, or the like, in which compression, condensation, expansion and evaporation stages are carried out. 
     A conventional rotary compressor assembly includes an airtight container including a driving motor and a compressing device or compressor therein, and an accumulator for supplying an evaporated refrigerant to the airtight container. The accumulator is contained in a cylindrical casing and communicates with the airtight container through a refrigerant pipe or conduit. A holder or bracket is used to mount the accumulator vertically on an outer wall of the airtight container, eccentrically with respect to axis of the container. 
     In order to fixedly mount the rotary compressor including the accumulator, a supporting plate is fixed to the underside of the airtight container by welding. More specifically, the rotary compressor is welded onto a center portion of the supporting plate, and supporting holes, into which rubber vibration isolating elements or dampening members are inserted, are formed at angular points of the supporting plate. Each isolating member has a through-hole extending along the central axis thereof, through which a bolt penetrates. With this arrangement, with the isolating elements inserted into the respective supporting holes of the supporting plate and the bolts fastened to a base plate, or other installation surface, of an air conditioner, or the like, through the vibration isolating members, the rotary compressor is fixed in place on, while being vibration isolated against from, the base plate. 
     A disadvantage of the above-described conventional rotary compressor assembly is that substantial vibration and noise occur during the operation of the driving motor and the compressing device in the airtight container and such vibration is directly transmitted to the base plate. This has a deleterious affect on other parts, significantly shortening the life of these parts. In addition, although the rubber vibration isolating elements are mounted at angular points of the supporting plate, because the rotary compressor is disposed on the supporting plate without regard to the weight of the accumulator attached eccentrically to the rotary compressor, the load is unevenly applied to the respective vibration isolating members. This limits the vibration and noise suppression provided. 
     SUMMARY OF THE INVENTION 
     The present invention is concerned with solving the problems discussed above and, to this end, it is an object of the present invention to provide a rotary compressor assembly in which the center of gravity of a rotary compressor, including an accumulator, is correspondingly disposed at the geometric center of a supporting plate for the compressor and accumulator so as to effectively reduce the vibration and noise occurring during the operation of the rotary compressor. 
     To achieve the above object, a rotary compressor assembly is provided which includes a rotary compressor, an accumulator mounted on an outer wall surface of the rotary compressor, a supporting plate on which the rotary compressor is fixedly mounted, a plurality of supporting holes which are formed on edge portions of the supporting plate, and a plurality of vibration isolating or dampening members received in the supporting holes so as to support the supporting plate in spaced relation to an installation surface, the center of gravity of the rotary compressor including the accumulator being located on the supporting plate in a predetermined relation to the geometric center of the supporting holes such that a uniform load is exerted on each of the vibration isolating members. 
     Preferably, the center of gravity of the rotary compressor including the accumulator and the geometric center of the supporting holes are disposed so as to coincide with each other on the supporting plate. 
     Advantageously, the supporting plate has a polygonal shape, and the supporting holes are formed in the vicinity of the respective apexes of the supporting plate. Preferably, the supporting plate has a triangular shape. 
     In an advantageous implementation, the accumulator is located on a line which connects the center of gravity of the rotary compressor including the accumulator to the apex of the supporting plate. 
     Further features and advantages of the present invention will be set forth in, or apparent from, the detailed description of preferred embodiments thereof which follows. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     The accompanying drawings, which are incorporated in and constitute a part of the specification, illustrate a preferred embodiment of the invention, and, together with the description, serve to explain the principles of the invention: 
     FIG. 1 is a perspective view of a rotary compressor assembly according to a preferred embodiment of the present invention; and 
     FIG. 2 is a plan view of the rotary compressor assembly of FIG. 1, as viewed in the direction indicated by arrow A in FIG.  1 . 
    
    
     DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS 
     A preferred embodiment of the present invention will now be described in detail with reference to the accompanying drawings. Referring to FIG. 1, a rotary compressor assembly is shown which comprises a rotary compressor  10  including an accumulator  20 , a supporting plate  30  for supporting the rotary compressor  10 , and a plurality of vibration isolating or dampening members  40 . 
     The rotary compressor  10  includes a cylindrical airtight container  11  to which a refrigerant supply pipe  13  and a discharge pipe  12  are coupled for providing intake and discharge of the refrigerant. The accumulator  20  is mounted vertically on an outer wall surface of the airtight container  11 . From the upper surface of the airtight container  11 , the discharge pipe  12  extends straight upwardly, as illustrated. An electrical input terminal  14  is installed on this upper surface and is supplied with electric power from an external source. A drive motor (not shown) powered from electrical terminal  14  and a compressing device or compressor (not shown) driven by the motor are provided inside of the airtight container  11 . 
     The accumulator  20  includes a cylindrical housing or casing  21 , and is fixedly mounted on an outer wall surface of the airtight container  11  by means of a holder or bracket  23 . 
     With the arrangement illustrated, any refrigerant which is not totally vaporized or evaporated in an evaporator (not shown) during the cooling cycle, flows into the accumulator  20  so as to completely evaporated therein, and the evaporated refrigerant flows into the airtight container  11  of the rotary compressor  10  through the refrigerant supply pipe  13 . To achieve this, the opposite ends of the supply pipe  13  are connected respectively to an outlet in the lower surface of the casing  21  of the accumulator  20  and to an outlet in the lower side-wall of the airtight container  11 . An inlet  22  through which the refrigerant is supplied to the accumulator  20  from the evaporator (not shown) is provided at the upper surface of the casing  21 . 
     The supporting plate  30  supports the rotary compressor  10  in upwardly spaced relation to an installation surface  50 , e.g., a base plate of an air conditioner, or the like. As shown in FIGS. 1 and 2, the supporting plate  30  is of a generally triangular shape. The airtight container  11  of the rotary compressor  10  is mounted on and affixed to a center portion of the supporting plate  30 , preferably by welding. In addition, a plurality of supporting holes  31   a,  31     b and  31     c  are provided which have predetermined diameters for receiving the vibration dampening members  40  and which are located in the vicinity of the three respective apexes  30   a ,  30   b  and  30   c  of the triangular supporting plate  30 . Each vibration dampening member  40  is made from rubber material and includes a central perpendicular through-hole  40   a.    
     When the vibration dampening members  40  are inserted into the respective supporting holes  31   a ,  31   b  and  31   c , corresponding mounting bolts  41 , installed on the installation surface  50  and extending upwardly therefrom penetrate through the respective through-holes  40   a  of the members  40 . Nuts  42  are then fastened onto the bolts  41 , thereby mounting the triangular supporting plate  30  and thus the airtight container  11  of the rotary compressor  10  in spaced relation to the installation surface  50 . 
     In order to effectively reduce the vibration and noise occurring during the operation of the rotary compressor  10 , the geometric center of the supporting holes  31   a ,  31   b  and  31   c  and the center of gravity G of the rotary compressor  10  including the accumulator  20 , are disposed so as to substantially coincide with respect to each other on the triangular supporting plate  30 . More specifically, as shown in FIG. 2, the accumulator  20  is located on a line L connecting the center of gravity G of the rotary compressor  10 , including the accumulator  20 , to the apex  30   c  of the triangular supporting plate  30 , and thus the center of gravity G of the rotary compressor  10 , including the accumulator  20 , is identical with the geometric center of the supporting holes  31   a ,  31   b  and  31   c  of the triangular supporting plate  30 . Accordingly, the vibration dampening members  40  have a uniform load exerted thereon and provide uniform support for the rotary compressor  10 . 
     The operation of the rotary compressor assembly of the present invention will now be described. The rotary compressor  10  begins operation upon being supplied with electric power. The refrigerant vaporized or evaporated in the evaporator (not shown) flows into the airtight container  11  via the accumulator  20  and the refrigerant supply pipe  13 . The refrigerant is then compressed at high temperature and high pressure, and supplied to the cooling cycle through the discharge pipe  12 , in a repeated or cyclic operation. At this time, the accumulator  20  prevents unsaturated refrigerant from flowing directly into the airtight container  11 . In other words, the refrigerant vaporized or evaporated in the evaporator (not shown) is supplied to the accumulator  20  through inlet  22 , and any liquid refrigerant which is not completely vaporized or evaporated is vaporized in the housing or casing  21  and exhausted or discharged into the airtight container  11  through the supply pipe  13 . 
     It is also noted that because the triangular supporting plate  30 , on which the rotary compressor  10  is mounted, is supported in spaced relation to the installation surface  50  by the three rubber vibration dampening members  40 , vibration occurring during the operation of the compressor  10  is effectively isolated, i.e., is prevented from being transmitted to the surroundings through the installation surface  50 . In addition, because the rotary compressor  10 , including the accumulator  20 , is disposed on the triangular supporting plate  30  with reference to the center of gravity G thereof, each vibration isolating member  40  supports the rotary compressor  10  in a stable manner. As a result, the load exerted by the rotary compressor  10  is uniformly applied to each member  40 , so vibration and noise occurring during the operation of the rotary compressor  10  is effectively further reduced. 
     It will be appreciated that the supporting plate can be of a different polygonal shape, than that shown, i.e., the supporting plate can be a rectangular plate rather than the triangular supporting plate illustrated. 
     As described above in some detail, according to a preferred embodiment of the present invention, the geometric center of the plurality of supporting holes formed in the supporting plate (into which the vibration isolating or dampening members are inserted) is disposed so as to coincide with the center of gravity of the compressor unit comprising the rotary compressor including the accumulator. As a result, the load is applied uniformly to each dampening member provided on the supporting plate, and the rotary compressor is supported in a stable manner, thereby effectively reducing vibration and noise associated with the compression operation. 
     Although the invention has been described above in relation to preferred embodiments thereof, it will be understood by those skilled in the art that variations and modifications can be effected in these preferred embodiments without departing from the scope and spirit of the invention.