GB2375813A

GB2375813A - A vapour compression refrigeration system

Info

Publication number: GB2375813A
Application number: GB0112274A
Authority: GB
Inventors: Albert Robert Lowes
Original assignee: Individual
Current assignee: Individual
Priority date: 2001-05-21
Filing date: 2001-05-21
Publication date: 2002-11-27
Also published as: GB0112274D0

Abstract

In a vapour compression refrigeration system, the liquid feed line from the condenser is connected to the inlet (12) of a valve housing. The liquid outlet (13) from the housing is connected to an expansion device. Any gas present in the liquid flow, rises to an area (9) in the housing, causing a float (10) to move downwardly. A lever (6) thereby pivots about an anchor point (7), opening valve (3) which allows the gas to escape through a connection (1) to return to the vapour compression refrigeration system downstream of the expansion device. Upon release of the gas the float will rise, closing the valve (3). The float could be replaced by a liquid optical detector in conjunction with an electrically operated valve.

Description

De-gassing Valve.

Background of the invention.

This invention relates to air conditioners and refrigeration systems and provides a method that enables the system to run successfully when the outside temperatures are low.

Description of prior art.

Previously systems have maintained the condensing temperatures by switching the condenser fan on and off, or fan speed control to maintain the temperature of the condensed refrigerant. Another method boosts the pressure of the refrigerant from the condenser with a pump, effectively increasing the boiling point of the refrigerant.

Objects and advantages.

Systems without any means to eliminate gas in the liquid line are often overcharged when the ambient temperature is low, as when most of the condenser is full with liquid the pressure increase eliminates any gas bubbles, this temporarily making the unit perform conectly. However when the ambient temperature is high compressor damage can occur.

This invention eliminates this problem without the disadvantages associated with other solutions. Fan speed control uses extra energy as the higher back pressure causes the compressor to draw extra power. The liquid pressurisation pump system adds a pump with a shorter life expectancy than the rest of the components, also the cost of the pump is high, as is the cost of necessary additional electrical connections.

Bubbles are more likely to occur while the air conditioner or refrigeration unit is turned off to maintain the correct operating temperature, or during a de-frost period. When the unit is restarted the valve can pass all or a large percentage of the refrigerant flow rapidly cooling the liquid feed line, then regulate gas flow in response to demand preventing bubbles from entering the expansion device. This automatic operation on demand provides maximum energy efficiency, and its low cost means it can be fitted to any size system.

Summary of the invention with the objectives.

The general object of the invention is to pass any bubbles that occur in the liquid feed line before the expansion device directly to the suction

side of the system, bypassing the small passage in the expansion device, thus preventing the loss of high power cooling associated with gas flowing though the expansion device instead of the intended liquid flow.

Description of the drawing Fig. 1 Figure 1 shows the valve according to the invention, Numerals in drawing, 1 Gas output connection 2 Valve seat 3 Valve 4 Body of the valve 5 Shaft 6 Connecting lever 7 Valve body anchor 8 Float anchor 9 Area where gas collects 10 Float I I Area where liquid collects 12 Liquid in connection 13 Liquid output connection The valve is connected in the refrigeration circuit of a vapour compression system, the liquid feed from the condenser is connected to 12, the liquid line to the expansion device is connected to 13, 1 is connected to the low pressure side of the refrigeration circuit down stream from the expansion device. If any gas is present the lower velocity of the flow within the valve body will allow separation, the gas rises and fills the area 9, the float will fall, shaft 5 prevents any turbulence from causing the float to contact the side of the valve body 4 jamming it, as 10 moves down it pulls down the lever 6, which is connected by a pivot to the float anchor point 8, the lever 6 when moved downwards pivots about the anchor point 7, and opens valve 3, away from its seat 2, allowing gas to flow out of the valve through connection 1, when the gas is released the float will rise lifted by the liquid, this will close the valve by the same coupling mechanism, liquid from connection 13 will have few or no bubbles, permitting effective operation of the expansion device. The example given is a description of the invention, and is not intended to limit the methods used to release the gas from the liquid, without departing from the spirit of the invention, a person skilled in the art would understand that the float could be replaced with a liquid detector, that could be an optical device, or a heated temperature sensor or other means that could detect the presence or absence of liquid, and that it could

operate an electrically operated valve, or solenoid, to release the gas to the low pressure side of the system bypassing the expansion device.

Claims

1aims (1) I claim a means to separate any gas present in the liquid feed line of a vapour compression system, and release the gas into a secondary circuit bypassing the expansion means, then return it back to the main circuit downstream of the aforesaid expansion means.