(under subclass 41.01) Cooling systems including (1) devices or arrangements for draining the entire cooling system or any part thereof, usually to prevent freezing, or (2) devices for storing heat to be returned to the system when the engine is stopped to prevent freezing.
(1) Note. The draining devices usually include a heat insulated tank into which the coolant is drained and stored.
(2) Note. Mere internal passages in a cooling system which are not closed in normal operation of the system are not considered draining devices, even though indented to allow complete emptying of the block or other port.
(3) Note. Heat storing devices must include something in addition to mere bulk of coolant or stopping of circulation.
SEE OR SEARCH CLASS
137, Fluid Handling, 59+, for drain valves operated in response to a sensing of freeze conditions; subclass 107 for drains responsive to flow stoppage; and subclasses 301+ for hydrants combined with means to prevent freezing.
417, Pumps,
434, for means for draining a pump or pump portion.
