An oxygen concentrator comprises a product tank that is fluidly coupled to at least one sieve bed, and a product gas accumulator tank that is fluidly coupled to the product tank via a first conduit and to an outlet port via a second conduit, wherein the first conduit and the second conduit are disposed to allow at least a portion of product gas to flow from the product tank to the outlet port.

An oxygen concentrator comprises a product tank that is fluidly coupled to at least one sieve bed, and a product gas accumulator tank that is fluidly coupled to the product tank via a first conduit and to an outlet port via a second conduit, wherein the first conduit and the second conduit are disposed to allow at least a portion of product gas to flow from the product tank to the outlet port.

The present invention provides a refrigerating and freezing device. A first sealed space and a second sealed space are disposed in a storage space inside the refrigerating and freezing device. The refrigerating and freezing device is further provided with a nitrogen generation device, which comprises an adsorption device and an air compressor that supplies compressed air for the adsorption device. The adsorption device utilizes the compressed air to prepare nitrogen that is provided for the first sealed space and an oxygen-enriched gas that is provided for the second sealed space. The freshness preservation capability of the first sealed space is improved. The bioactivity of food in the second sealed space is guaranteed.

The present invention provides a refrigerating and freezing device. A first sealed space and a second sealed space are disposed in a storage space inside the refrigerating and freezing device. The refrigerating and freezing device is further provided with a nitrogen generation device, which comprises an adsorption device and an air compressor that supplies compressed air for the adsorption device. The adsorption device utilizes the compressed air to prepare nitrogen that is provided for the first sealed space and an oxygen-enriched gas that is provided for the second sealed space. The freshness preservation capability of the first sealed space is improved. The bioactivity of food in the second sealed space is guaranteed.

An oxygen supplying apparatus includes: an oxygen enriching module including a plurality of oxygen enriching units; a pressure boosting module which receives the oxygen-enriched gas from the oxygen enriching module and boosts pressure of the oxygen-enriched gas; and a controller controlling operations of the oxygen enriching module and the pressure boosting module. The pressure boosting module includes: a low-pressure tank which receives and stores the oxygen-enriched gas from the oxygen enriching module; a pressure booster which boosts pressure of the oxygen-enriched gas discharged from the low-pressure tank; a high-pressure tank stores the oxygen-enriched gas pressure-boosted by the pressure booster; and at least one bypass valve which is provided to a bypass passage for bypassing a portion of the pressure-boosted oxygen-enriched gas stored in the high-pressure tank to the low-pressure tank to regulate bypassing of the oxygen-enriched gas from the high-pressure tank to the low-pressure tank.

An oxygen supplying apparatus includes: an oxygen enriching module including a plurality of oxygen enriching units; a pressure boosting module which receives the oxygen-enriched gas from the oxygen enriching module and boosts pressure of the oxygen-enriched gas; and a controller controlling operations of the oxygen enriching module and the pressure boosting module. The pressure boosting module includes: a low-pressure tank which receives and stores the oxygen-enriched gas from the oxygen enriching module; a pressure booster which boosts pressure of the oxygen-enriched gas discharged from the low-pressure tank; a high-pressure tank stores the oxygen-enriched gas pressure-boosted by the pressure booster; and at least one bypass valve which is provided to a bypass passage for bypassing a portion of the pressure-boosted oxygen-enriched gas stored in the high-pressure tank to the low-pressure tank to regulate bypassing of the oxygen-enriched gas from the high-pressure tank to the low-pressure tank.

A rotary control valve and a sieve bed module assembly for use in pressure swing adsorption processes to make enriched oxygen product gas for therapy in patients is disclosed. The valve includes a stepping motor with a single shaft extending between ends. At ends of the valve, an air side valve function and oxygen side valve function are provided. Each end includes a stationary plate (stator) with ports, and a disc (rotor) that rotates with the shaft, opening and closing ports to achieve the desired valve function. The valve is integrated into the assembly between two sieve beds and a product storage tank is directly coupled to the oxygen side. Placement of the motor, shaft, and movable parts in the valve and mounting of the beds, valve, and tank in the assembly, result in more compact designs. The motor can be programmed to obtain multiple, different PSA processes and flexibility.

A rotary control valve and a sieve bed module assembly for use in pressure swing adsorption processes to make enriched oxygen product gas for therapy in patients is disclosed. The valve includes a stepping motor with a single shaft extending between ends. At ends of the valve, an air side valve function and oxygen side valve function are provided. Each end includes a stationary plate (stator) with ports, and a disc (rotor) that rotates with the shaft, opening and closing ports to achieve the desired valve function. The valve is integrated into the assembly between two sieve beds and a product storage tank is directly coupled to the oxygen side. Placement of the motor, shaft, and movable parts in the valve and mounting of the beds, valve, and tank in the assembly, result in more compact designs. The motor can be programmed to obtain multiple, different PSA processes and flexibility.

This invention provides a method to smooth out the concentration peak generated from the regeneration stream of a cyclic adsorption process such as PTSA or TSA process. A fixed-bed adsorber (called a capacitor) to process the spent regeneration gas from a TPSA or TSA unit to maintain a constant composition of the spent regeneration gas to the downstream unit. The adsorber operates in a once-through non-cyclic manner, very similar to the conventional fixed bed reactor or adsorber. The spent regeneration gas stream coming out of the adsorber will have a more uniform CO.sub.2 composition than without the capacitor.

An object of the present invention is to provide a gas refining apparatus which can produce a product gas with high purity and high yield at low cost and can produce a plurality of types of gas as a product gas without changing an adsorbent, and the present invention provides a gas refining apparatus (10) including a first derivation line (L3) connected to the second adsorption towers (2a, 2b) and through which the first gas flows, a second derivation line (L4) connected to the second adsorption towers (2a and 2b) and through which the second gas flows, a regeneration line (L5) connected to the first adsorption towers (1a, 1b), through which a regeneration gas for regenerating a first adsorbent in the first adsorption towers (1a, 1b) flows, and a pump (P) provided in the second derivation line (L4) and configured to desorb the second gas from a second adsorbent in the second adsorption towers (2a and 2b), and the regeneration line (L5) is connected to each of the first derivation line (L3) and the second derivation line (L4).