Electromagnetic wave-activated sorption refrigeration system

• US 5,842,356 A
• Filed: 03/20/1997
• Issued: 12/01/1998
• Est. Priority Date: 09/20/1995
• Status: Expired due to Term

• Current Assignee: Oracle America, Inc. (Oracle Corporation)
• Original Assignee: Sun Microsystems Incorporated (Oracle Corporation)
• Inventors: Pfister, Dennis M., Byrd, Charles M.
• Primary Examiner(s): DOERRLER, WILLIAM CHARLES
• Application Number:
  US08/821,257
• Time in Patent Office: 621 Days
• Field of Search: 62/480, 62/497, 62/481, 62/148, 62/101, 62/476
• US Class Current: 62/480
• CPC Class Codes: F25B 17/08 the absorbent or adsorbent being a solid, e.g. salt F25B17/12 takes precedence
• CPC Class Codes: F25B 2333/005 the generator or boiler uses electromagnetic energy in the form of microwaves for desorbing the sorbate from the sorbate/sorbent compound
• CPC Class Codes: F25B 35/04 using a solid as sorbent
• CPC Class Codes: F25B 39/026 specially adapted for sorption type systems
• CPC Class Codes: F25B 49/046 Operating intermittently
• CPC Class Codes: F25D 23/12 Arrangements of compartments additional to cooling compartments; Combinations of refrigerators with other equipment, e.g. stove
• CPC Class Codes: H01L 23/427 Cooling by change of state, e.g. use of heat pipes by liquefied gas H01L23/445
• CPC Class Codes: H01L 2924/00 Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
• CPC Class Codes: H01L 2924/0002 Not covered by any one of groups H01L24/00, H01L24/00 and H01L2224/00
• CPC Class Codes: H05B 6/701 using microwave applicators
• CPC Class Codes: H05B 6/802 for heating fluids methods of heating fluids in conventional microwave ovens H05B6/687
• CPC Class Codes: H05B 6/808 Microwave heating adapted for vending machines
• CPC Class Codes: H05K 7/20363 Refrigerating circuit comprising a sorber

Abstract

A refrigeration system capable of providing cooling during at least a portion of a repeatable refrigeration cycle, the refrigeration system comprising at least one sorber having a housing forming an enclosure, a sorbent located within the enclosure, an evaporator in fluid communication with the enclosure, a condenser in fluid communication with both the enclosure and the evaporator, wherein a sorbate is evaporated in the evaporator to provide a cooling effect and then adsorbed by the sorbent, an electromagnetic wave generator, a waveguide coupler for coupling electromagnetic waves generated by the generating means to the sorber, wherein during a desorb portion of the refrigeration cycle the sorbate is desorbed from the sorbent by the electromagnetic waves and then condensed in the condenser, wherein the desorption of the sorbate from the sorbent is primarily isothermal, and a controller for controlling the operation of the generator, wherein the generator is selectively activated and deactivated to initiate and terminate, respectively, the desorb portion of the refrigeration cycle.

Claims

1. A refrigeration system capable of providing cooling during at least a portion of a repeatable refrigeration cycle, the refrigeration system comprising:

at least one sorber having a housing forming an enclosure;

a sorbent located within the enclosure;

the sorber including at least one port through which a sorbate may be communicated to the sorbent;

wherein the sorbate is adsorbed by the sorbent to form a sorbate/sorbent compound;

an electromagnetic wave generator;

means for coupling electromagnetic waves generated by the electromagnetic wave generator to the sorber;

wherein during a desorb portion of the refrigeration cycle electromagnetic waves transmitted by the electromagnetic wave generator are propagated through the enclosure to desorb the sorbate from the sorbate/sorbent compound;

wherein the sorbate/sorbent compound is not heated by the electromagnetic waves to a degree sufficient to thermally desorb the sorbate from the sorbate/sorbent compound;

a condenser connected to the sorber;

an evaporator connected between the condenser and the port; and

a controllable valve interposed between the condenser and the evaporator;

wherein sorbate which is desorbed in the sorber is condensed in the condenser and then, during an adsorb portion of the refrigeration cycle, controllably evaporated in the evaporator to create a cooling effect and drawn back into the sorber;

means for controlling the operation of the electromagnetic wave generator and the valve in response to preprogrammed instructions;

wherein the desorb and adsorb portions of the refrigeration cycle may be selectively regulated to provide a desired cooling effect.

2. The refrigeration system of claim 1, wherein the sorber comprises a hollow outer conductor and an inner conductor extending coaxially into the outer conductor, the inner and outer conductors being sized and spaced to form a waveguide for the electromagnetic waves.

3. A refrigeration system capable of providing cooling during at least a portion of a repeatable refrigeration cycle, the refrigeration system comprising:

at least one sorber having a housing forming an enclosure;

a sorbent located within the enclosure;

an evaporator in fluid communication with the enclosure;

a condenser in fluid communication with both the enclosure and the evaporator;

wherein a sorbate is evaporated in the evaporator to provide a cooling effect and then adsorbed by the sorbent;

means for generating electromagnetic waves;

means for coupling electromagnetic waves generated by the generating means to the sorber;

wherein during a desorb portion of the refrigeration cycle the sorbate is desorbed from the sorbent by the electromagnetic waves and then condensed in the condenser;

wherein the desorption of the sorbate from the sorbent is primarily isothermal; and

controller means for controlling the operation of the generating means;

wherein the generating means is selectively activated and deactivated to initiate and terminate, respectively, the desorb portion of the refrigeration cycle.

4. The refrigeration system of claim 3, further comprising:

means responsive to the controller means for regulating the power transmitted to the generating means from a source of electrical power;

wherein the power transmitted to the generating means is gradually increased to initiate the desorption of the sorbate from the sorbent and thereby increase the pressure in the enclosure at the beginning of the desorb portion of the refrigeration cycle.

5. The refrigeration system of claim 4, wherein the regulating means comprises a mosfet.

6. The refrigeration system of claim 3, further comprising:

means connected to the controller means for sensing the temperature of the generating means;

wherein the generating means is deactivated to thereby terminate the desorb portion of the refrigeration cycle when the temperature rises by a predetermined amount.

7. The refrigeration system of claim 3, further comprising:

a controllable valve in fluid communication with the evaporator and responsive to the controller means;

wherein the evaporation of the sorbate is controlled by the controller means.

8. The refrigeration system of claim 7, wherein the controller means actuates the valve prior to the initiation of the desorb portion of the refrigeration cycle to thereby increase the pressure in the enclosure at the beginning of the desorb portion of the refrigeration cycle.

9. A refrigeration system capable of providing cooling during at least a portion of a repeatable refrigeration cycle, the refrigeration system comprising:

at least one sorber having a housing forming an enclosure;

a sorbent located within the enclosure;

an evaporator in fluid communication with the enclosure;

a condenser in fluid communication with both the enclosure and the evaporator;

wherein a sorbate is evaporated in the evaporator to provide a cooling effect and then adsorbed by the sorbent;

means for generating electromagnetic waves;

means for coupling electromagnetic waves generated by the generating means to the sorber;

wherein during a desorb portion of the refrigeration cycle the sorbate is desorbed from the sorbent by the electromagnetic waves and then condensed in the condenser;

controller means for controlling the operation of the generating means;

wherein the generating means is selectively activated and deactivated to initiate and terminate, respectively, the desorb portion of the refrigeration cycle; and

means responsive to the controller means for regulating the power transmitted to the generating means from a source of electrical power;

wherein the power transmitted to the generating means is gradually increased to initiate the desorption of the sorbate from the sorbent and thereby increase the pressure in the enclosure at the beginning of the desorb portion of the refrigeration cycle.

10. The refrigeration system of claim 9, wherein the regulating means comprises a mosfet.

11. A refrigeration system capable of providing cooling during at least a portion of a repeatable refrigeration cycle, the refrigeration system comprising:

at least one sorber having a housing forming an enclosure;

a sorbent located within the enclosure;

an evaporator in fluid communication with the enclosure;

a condenser in fluid communication with both the enclosure and the evaporator;

wherein a sorbate is evaporated in the evaporator to provide a cooling effect and then adsorbed by the sorbent;

means for generating electromagnetic waves;

means for coupling electromagnetic waves generated by the generating means to the sorber;

wherein during a desorb portion of the refrigeration cycle the sorbate is desorbed from the sorbent by the electromagnetic waves and then condensed in the condenser;

controller means for controlling the operation of the generating means;

wherein the generating means is selectively activated and deactivated to initiate and terminate, respectively, the desorb portion of the refrigeration cycle; and

a controllable valve in fluid communication with the evaporator and responsive to the controller means;

wherein the evaporation of the sorbate is controlled by the controller means and wherein the controller means actuates the valve prior to the initiation of the desorb portion of the refrigeration cycle to thereby increase the pressure in the enclosure at the beginning of the desorb portion of the refrigeration cycle.

12. A method of providing a cooling effect during at least a portion of a refrigeration cycle, the method comprising the steps of:

providing a sorbent having a sorbate adsorbed thereon;

desorbing the sorbate from the sorbent using electromagnetic energy;

wherein the desorption of the sorbate from the sorbent is primarily isothermal;

condensing the desorbed sorbate;

evaporating the condensed sorbate to produce a cooling effect; and

controlling the duration of the desorbing and evaporating steps to provide a desired cooling effect.

13. The method of claim 12, further comprising the steps of:

providing an enclosure for the sorbent;

increasing the pressure in the enclosure immediately before or at the beginning of the desorbing step.