Abstract:
A temperature sensor on an outer surface of an upper shell at a location is associated with a discharge chamber. The temperature sensor includes electronics molded into an overmolded plastic and includes a spring member. The spring member snaps into a sensor housing connected to the outer surface.

Description:
BACKGROUND OF THE INVENTION 
       [0001]    This application relates to a temperature sensor, which may be associated with an upper shell of a scroll compressor housing and which snaps into a protected sensor housing. 
         [0002]    Scroll compressors are known and, typically, include a first scroll member having a spiral wrap extending from a base. A second scroll member also has a spiral wrap extending from its base. The two spiral wraps interfit to define compression chambers. One of the two scroll members is caused to orbit relative to the other. As this movement occurs, the size of the compression chamber is decreased and refrigerant is compressed. 
         [0003]    There are many challenges with operating scroll compressors. Several conditions can cause the temperatures within the scroll compressor to reach unduly high levels. Thus, it is known to have a shutoff switch associated with a motor for the scroll compressor. 
         [0004]    Scroll compressor motors often have a shutoff switch incorporated within a housing shell that houses the motor and the two scroll members. This is not always as sensitive as would be desired. Thus, it has also been proposed to incorporate temperature sensors on the housing shell. However, providing a mount for a temperature sensor that will protect the temperature sensor and is also a location that provides good feedback of the internal temperature has been challenging. 
       SUMMARY OF THE INVENTION 
       [0005]    A scroll compressor has a housing shell including a cylindrical lower portion and an upper cover portion. The upper cover portion has an outer surface. A scroll compressor pump unit includes a first scroll member having a base and a generally spiral wrap extending from its base. A second scroll member having a base and a generally spiral wrap extending from its base. The wraps of the first and second scroll members interfit to define compression chambers. The first scroll member has a discharge port. An electric motor drives a drive shaft to rotate and, in turn, causes the second scroll member to orbit relative to the first scroll member and to decrease volume of the compression chambers such that a refrigerant is compressed. The refrigerant is driven towards the center of the first and second scroll member wrap to communicate with the discharge port. A discharge pressure plenum is defined inwardly of the upper shell and communicates with the discharge port. A temperature sensor connects to the outer surface of the upper shell at a location associated with the discharge plenum. The temperature sensor includes a temperature sensor member that includes electronics molded into an overmolded plastic and includes a spring member. The spring member snaps into a housing member welded to the outer surface. 
         [0006]    These and other features may be best understood from the following drawings and specification. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0007]      FIG. 1  schematically shows a scroll compressor. 
           [0008]      FIG. 2A  shows a sensor. 
           [0009]      FIG. 2B  shows the sensor mounted on a housing for the scroll compressor. 
           [0010]      FIG. 3  is a cross-sectional view through the sensor and the sensor housing. 
           [0011]      FIG. 4  shows a spring. 
           [0012]      FIG. 5  shows the insertion of the sensor into the sensor housing. 
           [0013]      FIG. 6  shows another embodiment. 
       
    
    
     DETAILED DESCRIPTION 
       [0014]      FIG. 1  shows a scroll compressor  20  including a lower housing cylindrical portion  32  and an upper shell  30  closing off the housing. A non-orbiting scroll member  28  has a spiral wrap  29  extending from a base. An orbiting scroll member  26  has a spiral wrap  27  extending from its base. The wraps interfit to define compression chambers  15 . A motor  22 , which may be a variable speed motor, causes a drive shaft  24  to rotate. A non-rotating coupling, which may be an Oldham coupling  25  causes the orbiting scroll member  26  to orbit relative to the wraps  29  of the non-orbiting scroll  28 . As this occurs, a refrigerant entrapped in the compression chambers  15  is compressed and driven towards a discharge port  18 . Discharge port  18  communicates with a discharge chamber  19 , such that refrigerant having been compressed is delivered into the compression chamber  19 . 
         [0015]    A suction tube  129  is connected to a source of refrigerant and may be connected within shell  32 . 
         [0016]    A temperature sensor  50  is illustrated being positioned on an outer surface of the upper shell  30  and generally aligned to be over the port  18 . The temperature sensor  50  is sensitive to the temperature within the chamber  19 . Should the temperature reach an unduly high level, this will be sensed by a control  44 , which can operate to shut down motor  22 . 
         [0017]      FIG. 2A  shows a detail of the sensor  50 . An overmolded plastic body  52  protects the internal electronics. A spring  54  has an upper bias member  55  and side legs  53  connected onto the overmolded plastic body  52 . A tab  56  provides a stop to ensure that the sensor  50  is not inserted into a housing  60  (See  FIG. 3 ) in a vertically incorrect orientation.  FIG. 2B  shows the sensor  50  mounted within a housing  60  on the upper surface  59  of the upper shell  30 . 
         [0018]    As shown in  FIG. 3 , the housing  60  is welded to an upper surface  59  of the upper shell housing  30 . Electronics  62  are mounted within the overmolded housing  52  and communicate with a wire  64 , which, in turn, communicates with the control  44 . 
         [0019]    The spring extends upwardly to contact a wall  68  of an opening  69  in the housing  60 . The stop  56  abut a surface  58  of the housing  60  to provide a stop surface. 
         [0020]      FIG. 4  shows details of the spring  54  including the bias portion  55  and the legs  53 . As can be appreciated, the legs  53  fit into slots, one on the side of the overmolded body  52 . (See  FIG. 2A  and  FIG. 5 ). Alternatively, the spring could be attached to body  52  without legs, such as by being hot-staked.  FIG. 5  shows the sensor  50  being inserted into the housing  60 . As can be appreciated from  FIG. 3 , the bias member  55  provides a bias force holding the electronics  62  against the surface  59 . However, a technician can manipulate, through the opening  69 , to move the bias portion  68  inwardly to allow removal of the sensor  50 . Further, the housing portion  58  will bend the bias portion  59  inwardly to allow insertion such as shown generally in  FIG. 5 . 
         [0021]      FIG. 6  shows another embodiment  100  wherein the spring member  108  has a bias member  104  extending upwardly further into the opening  106 . 
         [0022]    The sensor electronics  62  be a thermistor. The scroll compressor housing and the spring may be metallic. 
         [0023]    Although an embodiment of this invention has been disclosed, a worker of ordinary skill in this art would recognize that certain modifications would 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.