Air conditioning and refrigeration systems utilizing a cryogen
AssigneeThermo King Corporation
InventorsHerman H. Viegas, Roland L. Roehrich, Dale T. Johnson
Life of this patent
Estimating the term…
Abstract
Air conditioning and refrigeration methods and apparatus for controlling the temperature of a conditioned space to a predetermined temperature band adjacent to a predetermined set point temperature via cooling and heating cycles utilizing a supply of pressurized cryogen. A fluid flow path for the cryogen includes a heat exchanger associated with the conditioned space. A cryogen heater is connected in the active cryogen flow path during a heating cycle, and cryogen is directed through the heater and heat exchanger via at least two successive serial passes, utilizing the elevated pressure energy of the cryogen as the motive force.
Claims26
A method of reducing the amount of cryogen consumed during a heating cycle of a refrigeration system which utilizes a supply of pressurized cryogen, which includes cryogen in a liquid state, with the cryogen being circulated through a cryogen flow path which includes heat exchanger means located to control the temperature of a conditioned space to a predetermined temperature band adjacent to a predetermined set point temperature via cooling and heating cycles, the heating cycle comprising the steps of:
- heating the cryogen a first time,
- passing the heated cryogen through the heat exchanger means a first time,
- heating the cryogen a second time, after it has passed through the heat exchanger means,
- and passing the re-heated cryogen through the heat exchanger means a second time.
A method for controlling the temperature of a conditioned space comprising the steps of:
- providing a pressurized supply of cryogen which includes cryogen in a liquid state,
- providing a fluid flow path for the cryogen,
- providing heat exchanger means in the flow path,
- providing a cooling cycle by passing cryogen through the heat exchanger means,
- and providing a heating cycle by the steps of heating the cryogen in response to a predetermined condition, passing the heated cryogen through the heat exchanger means, and repeating the steps of heating the cryogen and passing the heated cryogen through the heat exchanger means until the pressure of the cryogen falls below a predetermined value.
A refrigeration system for controlling the temperature of a conditioned space to a predetermined temperature band adjacent to a predetermined set point temperature via heating and cooling cycles, including a supply of pressurized cryogen which includes cryogen in a liquid state, a flow path for the cryogen, heat exchanger means in the cryogen flow path associated with the conditioned space, control means for selectively configuring the cryogen flow path to provide cooling and heating cycle cryogen flow paths, and cryogen heating means in the heating cycle cryogen flow path, the improvement comprising:
- said heating means and said heat exchanger means each having at least first and second cryogen flow paths,
- said control means configuring the cryogen flow path during a heating cycle to successively direct cryogen in first and second passes through the cryogen heating means and the heat exchanger means via the first and second cryogen flow paths of the heating means and the first and second cryogen flow paths of the heat exchanger means.
Dependencies are inferred from the claim text.