Molded core filter drier with filter media molded to core for use in heat pump systems

A filter-drier for drying refrigerant circulated in a heat pump refrigeration system by removing moisture therefrom, the filter-drier comprising:

• a casing having an inlet for receiving refrigerant and an outlet for discharging refrigerant, and opposed end plates each having inlet and outlet openings having check valves defining the direction of the flow;
• a molded core including inlet and outlet end portions having a through passage therebetween said core being disposed in said casing and held in place between said opposed end plates and receiving flow of refrigerant therethrough, said core including opposed inlet and outlet end faces and said passage being cylindrical;
• and
• a filter media including a cylindrical portion lining said passage and annular end portions, said filter media being molded to said core.

A method of manufacturing a filter-drier desiccant core for a heat pump filter-drier having a tubular casing and a two-way valve system to provide two-way flow through the core between an inlet and an outlet comprising the steps of:

• providing a tubular mold to form the outer diameter of the core;
• providing a center post within the tubular mold to form the inner diameter of the core;
• providing a mold base associated with the tubular mold at one end of the core;
• placing a filter media over the mold base and the center post;
• depositing a desiccant/binder within the mold and over the filter media;
• placing a filter media over the desiccant/binder to form the other end of the core to bond the filter media to the core;
• and.
• removing the mold when the core has set.