Abstract:
A compressor is provided with a fluid tight electrical connector. The electrical connector is sealed against the compressor housing, and a cable is attached to the connector housing. Since the cable is separately attached to the connector housing, it is not directly connected to the electrical pins in the compressor. This reduces damage to those pins. Further, unique sealing arrangements make the electrical connection fluid tight.

Description:
BACKGROUND OF THE INVENTION  
         [0001]    This invention relates to a sealed power supply connection for a sealed compressor canister.  
           [0002]    Compressors are typically mounted within a sealed housing structure. The sealed housing structure receives a compressor pump unit and an electric motor for driving the compressor pump unit. Refrigerant and oil are allowed to flow within the compressor housing to perform various functions such as cooling the motor, etc. Due to this refrigerant fluid and vapor flow within the compressor housing, the housings must be fully fluid-tight.  
           [0003]    There have been some challenges in connecting power supply connections to the compressor housing while still achieving a fluid-tight structure for the compressor housing. Typically, a series of terminal pins are mounted within a side wall of the connector. A cable has been connected to those terminal pins to supply power to the electric motor.  
           [0004]    These connections have been deficient in several regards. First, there has not always been a fully fluid-tight connection at the connection of the connector housing.  
           [0005]    In addition, the mount of the cable has typically been directly to the terminal pins. In this way, when the cable is removed from the connector, there has been damage to the terminal pin connections, since it is a single connector with fragile ceramic connectors.  
           [0006]    Further, this type of connection has not been adaptable to applications where the compressor may sometimes be submerged in water.  
         SUMMARY OF THE INVENTION  
         [0007]    In a disclosed embodiment of this invention, a separate connector housing is attached to a compressor housing wall. The cable is connected to a connection at one end of the housing, and the terminal pins from the connector housing are received within mating pin structure within the connector block. The connector block has appropriate circuitry for communicating the pins in the housing wall to the connectors for the cable at the other end of the connector. The connector housing is preferably attached to the connector wall with some mechanical attachment structure. In one embodiment, bolts are utilized. Preferably, bolt bosses are welded to the outer surface of the connector housing to receive the mechanical attachment bolts. The cable is separately connected to the connector housing such that when the cable is removed, there is no force on the terminal pins in the connector housing.  
           [0008]    Structurally, the connector housing preferably includes an internal wall which receives a connector block to receive the terminal pins. This housing provides proper positioning for the terminal block such that the terminal block is properly received. A strap secures the terminal block within the housing wall. The terminal block is preferably formed with openings to receive the terminal pins from the compressor housing, and has appropriate circuitry connected to the terminal pins for the cable.  
           [0009]    Further, sealing elements are preferably placed on the connector housing to surround the connection of the terminal pins within the compressor housing. Further sealing elements are placed in the housing at appropriate locations to define a fluid-tight seal. Also, the entire interior of the housing is preferably encased in a filler material such as a potting material, further enhancing the fluid-tight seal.  
           [0010]    These and other features of the present invention can be best understood from the following specification and drawings, the following of which is a brief description. 
       
    
    
       [0011]    [0011]                                         BRIEF DESCRIPTION OF THE DRAWINGS                                    is a perspective view of a compressor incorporated in the           inventive connector housing.           is the compressor of FIG. 1 without the connector housing.           is a cross-sectional view through the connector housing.           is a cross-sectional view along a different plane from           that of FIG. 3, and through the connector housing.           shows a portion of the connector housing.           is a cross-sectional view generally along lines 6-6           as shown in FIG. 5.           is a view through a housing portion according to the           present invention.           schematically shows the connections of the present invention.           is a bottom view of the connector housing.           shows the housing lid.           is a cross-sectional view along line 11-11 of FIG. 10.                    
     
    
     DETAILED DESCRIPTION  
       [0012]    A compressor  20  includes a housing shell  22  which seals a compressor pump unit and motor, as known. An electrical power connector housing  24  is attached to the housing  22 . A cable  26  is secured to the connector housing  24  and supplies electrical power to the compressor  20 .  
         [0013]    As shown in FIG. 2, the compressor housing  22  includes an electrical connection at  28 . Connection  28  includes pins  30  received within a weld ring  29 . The weld ring is welded to the wall  22  and pins  30  are connected to the motor. The structure of the pins is better described in co-pending patent application Ser. No. 09/105,135, entitled “INTEGRAL GROUND PIN FOR SEALED COMPRESSOR”.  
         [0014]    The connector housing  24  is shown attached to the compressor housing  22  in FIG. 3. As shown, the pins  30  extend through openings  31  in the connector housing. A main housing body  36  receives a cover  38  and  40 , and bolts  42  extend into the bosses  32  to secure the connector  24  to the housing. An internal wall  44  receives a block  46  which communicates electrical signals from the pins  32  to the cable  26 , as will be explained below. A strap  48  secures the block  46  within the housing. The space  57  surrounding the block and strap is filled with a filler material, such as an epoxy potting material. A groove  49  of the main housing  36  is supplied within a tough epoxy sealant, such that the connection between the main housing  36  and the covers  38  and  40  provides a fluid type seal. The drawings schematically show a compressor pump  51  which is driven by a motor  55 . A power supply  57  supplies power from the pins  30  to the wires  57 , and through to the motor  55 . The power supply is preferably a three-phase power supply, and preferably there are four pins, with one of the pins supplying a ground. This is the invention of the above-referenced patent application. A seal  53  seals between a forward face of the main housing body  36  and the outer compressor housing  22 . A space  17  spaces weld ring  29  from the main body housing  36 . The combination of all of the sealing provides a fluid type seal such that this compressor could be placed in a submerged location, and yet water would not leak into the connector. A separate cable connector member  50  is inserted into the main housing body  36 , and includes appropriate seals for providing a fluid type seal between the cable  26  and the cable connector  50 . Again, the fluid type seal will allow the entire compressor will be submerged. Since the cable is connected to a separate part, it can be easily removed without applying any force to the pins  30 . Thus, damage which may have occurred in the past is avoided.  
         [0015]    Weld bosses  32  are welded to the other surface of the housing  22  and receive bolts to connect the connector housing  24 , as will be described below.  
         [0016]    [0016]FIG. 4 shows housing  24  including a flat for sealing ring  53  which seals on the outer surface of the compressor housing  22 . A wall  44  receives bolts  56  to secure the strap  48 . A plurality of openings  54  are formed within block  36  to receive the pins  30 . As shown, potting material  57  fills the housing  24 .  
         [0017]    [0017]FIG. 5 shows the wall  44  within the interior of the connector housing portion  36 . A sealing lip  58  surrounds an opening into the main connector body  36 . The cover  40  is received on the housing member  36  to close this opening. The sealing lip  58  provides a fluid type seal at that connection.  
         [0018]    As shown in FIG. 6, the sealing lip  58  extends outwardly of member  36 .  
         [0019]    As shown in FIG. 7, a sealing element  53  surrounds the inner surface of the housing member  36 .  
         [0020]    [0020]FIG. 8 schematically shows the connector block  46  receiving the pins  30 . Appropriate wiring  52  connects the pins  30  to a cable connector  60  having associated pin  62 . Although pins are shown at both  30  and  62 , it should be understood that either or both of these elements could be receptors rather than the pin elements.  
         [0021]    [0021]FIG. 9 shows the housing  36 , and the cable connector  60  including the pins  62 . The curved surface  67  of the housing  36  faces the outer periphery of the curved housing  22  and provides a splash guard. Since the inventive compressor may well be utilized in applications where it will be exposed to water, the splash guard prevents water from reaching the seal between the connector housing and the compressor housing. The inventive connector is especially directed to compressors which are utilized in refrigeration transport containers. That is, refrigerated containers transported on boats, etc. Such compressors may well be exposed to water, and the invention is thus directed to providing a very good seal for this application.  
         [0022]    As can be seen in FIG. 9, there is a flat surface  99  radially inwardly of the curved surface  67 . That flat surface receives the seal  53  such as shown in FIG. 3. The combination of the flat surface and the curved surface ensure that there is a fluid tight seal at the compressor housing, and that that seal is not exposed to an undue amount of water due to the splash guard of the curved surface  67 .  
         [0023]    [0023]FIG. 10 shows lid  40 . As shown, groove  49  surrounds the periphery of the lid. A sealant, preferably an epoxy sealant  100  is placed in the groove  49  before the lid is placed on the main housing. The groove and sealant then seals on to the tongue  101  on the main housing such as shown in FIG. 3.  
         [0024]    While an epoxy is the preferred filler material in this application, other filler materials such as RTB, silicone materials, etc., can be utilized.  
         [0025]    A preferred embodiment of this invention has been disclosed; however, a worker of ordinary skill in the art would recognize that certain modifications come within the scope of this invention. For that reason, the following claims should be studied to determine the true scope and content of this invention.