Internal refrigerating machine heat exchanger

Abstract

An internal refrigerating machine heat exchanger ( 11 ) which increases the efficiency of the refrigerating machine ( 10 ) comprises a pipe having an internally arranged low-pressure channel and having a substantially larger cross-section than all of the high-pressure channels provided on the outside of the pipe. In addition, the inside width of the low-pressure channel is at least as large as the inside width of the connecting lines ( 17, 21 ). Preferably, the wall of the low-pressure channel is smooth.

1 . Internal refrigerating machine heat exchanger ( 11 ), consisting of a pipe ( 22 ) that is designed for the connection to the suction side of a coolant compressor ( 2 ) and that comprises high-pressure channels ( 27 ) which are designed for the connection to the pressure side of the coolant compressor ( 2 ), whereby:
 a. the low-pressure channel ( 25 ) has a substantially cylindrical cross-section defining an internal cross-sectional area;   b. the high-pressure channels ( 27 ) are arranged around the low-pressure channel ( 25 ) and are separated from each other by radially arranged intermediate walls ( 29 ,  30 ), in which case the sum of their respective cross-sectional areas defines an external cross-sectional area, and;   c. the internal cross-sectional area is larger than the external cross-sectional area.   
   
   
       2 . Heat exchanger in accordance with  claim 1 , characterized in that the internal cross-sectional area ( 25 ) is larger than 1.6 times the external cross-sectional area. 
   
   
       3 . Heat exchanger in accordance with  claim 1 , characterized in that the low-pressure channel ( 25 ) is enclosed by a smooth, non-ribbed wall ( 26 ). 
   
   
       4 . Heat exchanger in accordance with  claim 1 , characterized in that the pipe ( 22 ) consists of extruded light metal. 
   
   
       5 . Heat exchanger in accordance with  claim 1 , characterized in that each high-pressure channel ( 27 ) is limited by one radially internal wall section ( 28 ), two radially oriented wall sections ( 29 ,  30 ) and one radially external wall section ( 31 ), and that the portion of the radially internal wall section ( 28 ) adjacent the channel ( 27 ) is longer than the radial wall sections ( 29 ,  30 ). 
   
   
       6 . Heat exchanger in accordance with  claim 5 , characterized in that the portion of the radially internal wall section ( 28 ) adjacent the channel ( 27 ) is longer than twice the radial wall sections ( 29 ,  30 ). 
   
   
       7 . Heat exchanger in accordance with  claim 5 , characterized in that the portion of the radially internal wall section ( 28 ) adjacent the channel ( 27 ) is longer than three times the radial wall sections ( 29 ,  30 ). 
   
   
       8 . Heat exchanger in accordance with  claim 1 , characterized in that the number of external high-pressure channels ( 27 ) is at most 10. 
   
   
       9 . Heat exchanger in accordance with  claim 1 , characterized in that the number of external high-pressure channels ( 27 ) is at most 8. 
   
   
       10 . Heat exchanger in accordance with  claim 1 , characterized in that the number of external high-pressure channels is at most 6. 
   
   
       11 . Heat exchanger in accordance with  claim 1 , characterized in that the pipe ( 22 ) has a circular outside profile. 
   
   
       12 . Heat exchanger in accordance with  claim 11 , characterized in that the outside diameter of the pipe ( 22 ) is less than or equal to 25 mm. 
   
   
       13 . Heat exchanger in accordance with  claim 1 , characterized in that the low-pressure channel ( 25 ) of the pipe ( 22 ) is provided with a connector ( 37 ), from which extends the connector ( 19 ) of the low-pressure channel in axial direction. 
   
   
       14 . Heat exchanger in accordance with  claim 1 , characterized in that the low-pressure channel ( 25 ) has a width which is at least as large as the width of its connector ( 19 ). 
   
   
       15 . Heat exchanger in accordance with  claim 1 , characterized in that the low-pressure channel ( 25 ) has a width which is at least as large as the width of the connected lines ( 17 ,  21 ). 
   
   
       16 . Heat exchanger in accordance with  claim 1 , comprising:
 a coupling device ( 101 );   a receiving component ( 104 ) having a receiving opening ( 109 ) changing to a fluid channel ( 110 ), said receiving opening being provided with an inward-directed shoulder ( 112 );   a coupling plug ( 105 ) having a tubular extension ( 108 ) which contains a fluid channel ( 137 ), whereby said plug can be inserted in the receiving opening ( 109 ) and whereby said plug's external circumferential face defines a gap with the shoulder ( 112 ); and,   a coupling housing ( 106 ), which has a passage opening ( 119 ) for passage of the coupling plug ( 105 ) and is provided with a locking means ( 135 ) for axially securing the coupling plug ( 105 ) in the receiving component, and which has on its face side facing the coupling bushing ( 104 ) at least one catch means ( 112 ,  116 ,  117 ,  118 ) that interacts with the coupling bushing ( 104 ).   
   
   
       17 . Heat exchanger in accordance with  claim 1 , comprising:
 a coupling device ( 101 );   a receiving component ( 104 ) having a receiving opening ( 109 ) changing to a fluid channel ( 110 ), said receiving opening being provided with an inward-directed shoulder ( 112 );   a coupling plug ( 105 ) having a tubular extension ( 108 ) which contains a fluid channel ( 137 ), whereby said plug can be inserted in the receiving opening ( 109 ) and whereby said plug's external circumferential face defines a gap with the shoulder ( 112 ), whereby the fluid channel has an inside diameter which matches the inside diameter of the low-pressure channel ( 25 ).   
   
   
       18 . Refrigerating machine, comprising:
 a compressor ( 20 ) having an inlet ( 4 ) and an outlet ( 3 );   a condenser ( 6 ) that is connected to the outlet ( 3 ) of the compressor ( 2 );   an evaporator ( 16 ) to which the compressed coolant is fed via an expansion valve ( 15 ); and,   an internal heat exchanger ( 11 ) in accordance with one of the previous claims, said heat exchanger being arranged between the evaporator ( 16 ), the compressor ( 2 ) and the condenser ( 6 ) in order to heat the coolant fed to the compressor ( 20 ) and to cool the coolant fed to the evaporator ( 16 ).