Accumulator with pickup tube

Abstract

A suction accumulator for refrigeration or air-conditioning system use, especially for automotive air conditioning system use, which comprises a “pickup tube” to withdraw liquid from a reservoir of the accumulator to return oil to the compressor. The accumulator has a deflector with an outlet tube, to help ensure that fluid does not flow directly from the inlet opening to the outlet opening of the accumulator. The relatively narrow second portion of the outlet tube is closer to the outlet opening than the first portion. The pickup tube is secured in communication with the relatively narrow second portion and optimises the oil return function, minimises restriction to refrigerant flow, maximises effective and actual reservoir volume, and minimises the amount of liquid delivered to the compressor at switch-off. Incorporating an electric heating element or a heat exchanger for engine coolant or exhaust allows the accumulator of the present invention to function as the evaporator when the refrigeration system is used in heat pump mode for heating applications.

1 . An accumulator comprising 
 an inlet opening,    an outlet opening,    a deflector to help ensure that liquid does not flow directly from the inlet opening to the outlet opening,    a conduit inside the accumulator in communication with the outlet opening, the conduit comprising a conduit wall surrounding an open interior, the open interior having a first portion and a second portion, the second portion having a cross-sectional area less than a cross-sectional area of the first portion and the second portion being closer to the outlet opening than the first portion,    a pickup tube having a first end and a second end, the second end being in communication with the second portion of the open interior.    
   
   
       2 . The accumulator of  claim 1  wherein the first end of the pickup tube is adapted to extend into liquid accumulated within the accumulator.  
   
   
       3 . The accumulator of  claim 2  wherein the conduit wall has a passageway formed therein extending from the second portion of the open interior through at least part of the conduit wall and the second end of the pickup tube being secured in communication with the second portion of the open interior via the passageway.  
   
   
       4 . The accumulator of  claim 2  wherein the conduit forms part of the deflector.  
   
   
       5 . The accumulator of  claim 2  wherein the conduit comprises one or more parts.  
   
   
       6 . The accumulator of  claim 3  wherein the passageway extends from the open interior of the conduit to an exterior of the conduit wall.  
   
   
       7 . The accumulator of  claim 4  wherein the deflector is secured to the outlet opening.  
   
   
       8 . The accumulator of  claim 2  wherein the inlet opening and the outlet opening are both located in a top of the accumulator.  
   
   
       9 . The accumulator of  claim 2  wherein the inlet opening is located in a top of the accumulator and the outlet opening is located in a side of the accumulator.  
   
   
       10 . The accumulator of  claim 2  wherein the inlet opening and the outlet opening are both located in one or more sides of the accumulator.  
   
   
       11 . The accumulator of  claim 2  wherein the pickup tube comprises a means to trap liquid in the pickup tube if suction within the pickup tube is stopped or if suction is insufficient to draw liquid up the pickup tube.  
   
   
       12 . The accumulator of  claim 11  wherein the means to trap liquid comprises a ball valve.  
   
   
       13 . The accumulator of  claim 2  wherein the pickup tube comprises a filter located at a lower end of the pickup tube.  
   
   
       14 . The accumulator of  claim 2  wherein the pickup tube has several openings at different heights above the floor of the accumulator.  
   
   
       15 . The accumulator of  claim 2  further comprising heat exchanger coils.  
   
   
       16 . The accumulator of  claim 2  wherein the open interior tapers smoothly from the first portion to the second portion.  
   
   
       17 . The accumulator of  claim 2  wherein an entrance to the open interior of the first portion is gently flared.  
   
   
       18 . An accumulator comprising 
 an inlet opening,    an outlet opening,    a means to help ensure that liquid does not flow directly from the inlet opening to the outlet opening,    an outlet conduit means inside the accumulator in communication with the outlet opening, the outlet conduit means comprising an open interior, the open interior having a first portion and a second portion, the second portion having a cross-sectional area less than a cross-sectional area of the first portion and the second portion being closer to the outlet opening than the first portion,    a pickup conduit means in communication with the second portion of the open interior.    
   
   
       19 . The accumulator of  claim 18  wherein one end of the pickup conduit means is adapted to extend into liquid accumulated within the accumulator.  
   
   
       20 . The accumulator of  claim 18  wherein the means to help ensure that liquid does not flow directly from the inlet opening to the outlet opening is a deflector.  
   
   
       21 . The accumulator of  claim 2  further comprising one of engine coolant coils and electric heating coils.  
   
   
       22 . The accumulator of  claim 21  for use as an evaporator.