Cryogenic refrigerating apparatus

Claim 2

Cryogenic refrigerating apparatus of the type comprising a supply vessel to contain a supply of refrigerating liquid, and an evaporator to be mounted in heat exchange relationship with a load to be cooled, and connected to the supply vessel by a supply pipe of substantial length for the supply of refrigerant liquid to it, in which the supply vessel is provided with an injector having a liquid inlet communicating with the vessel below the liquid surface, and a gas inlet communicating through a pressure control device with a point in the supply vessel above the liquid surface to produce a flow of gas entraining drops of liquid into the supply pipe.

Claim 3

Apparatus as claimed in claim 1 in which the supply vessel is provided with a relief valve leading to an exhaust vent, so that if the pressure in the supply vessel rises above a predetermined value, gas is allowed to escape.

Claim 4

Cryogenic refrigerating apparatus comprising a supply vessel to contain a supply of refrigerating liquid, an evaporator to be mounted in heat exchange relationship with a load to be cooled, a supply pipe of substantial length connecting the supply vessel to the evaporator for the supply of refrigerant liquid to the latter, said pipe forming the sole connection between the supply vessel and the evaporator, and means including a valve adjacent the evaporator responsive to the level of liquid refrigerant in it, for automatically reducing or cutting off the flow of refrigerant when the liquid in the evaporator rises above a given level, without relying on lowering the pressure in the supply vessel, and an injector haviNg a liquid inlet communicating with the supply vessel below the liquid surface and a gas inlet communicating with it above the liquid surface to produce a flow of gas entraining drops of liquid into the supply pipe.

Claim 5

Cryogenic refrigerating apparatus comprising a supply vessel to contain a supply of refrigerating liquid, an evaporator to be mounted in heat exchange relationship with a load to be cooled, a supply pipe of substantial length connecting the supply vessel to the evaporator for the supply of refrigerant liquid to the latter, said pipe forming the sole connection between the supply vessel and the evaporator, and means including a valve adjacent the evaporator responsive to the level of liquid refrigerant in it, for automatically reducing or cutting off the flow of refrigerant when the liquid in the evaporator rises above a given level, without relying on lowering the pressure in the supply vessel, and an injector haviNg a liquid inlet communicating with the supply vessel below the liquid surface and a gas inlet communicating with it above the liquid surface to produce a flow of gas entraining drops of liquid into the supply pipe.

Claim 6

Apparatus as claimed in claim 3 including a venting device situated adjacent that end of the supply pipe which is adjacent the load and comprising a vented annular chamber surrounding the supply pipe and communicating with its interior through a number of perforations formed in its wall and distributed around its periphery.

Claim 7

Apparatus as claimed in claim 4 in which the supply pipe extends vertically where it passes through the annular chamber.