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US 3,964,175 AGranted
Coffee roasting system
OwnerMichael Sivetzinventor
Life of this patent
Estimating the term…
Abstract
A coffee bean roasting system is disclosed wherein coffee beans in a box-like chamber are levitated as a dense, uniformly recirculating mass by an upwardly directed airstream. The air is heated to a temperature not in excess of 530.degree.F., and the heat is transferred to the beans primarily by convection and secondarily by conduction from bean to bean. Heat transfer continues until after a thermally induced pyrolitic reaction has occurred within the bean mass and the desired roast has resulted whereupon the roasted beans are cooled. The system may employ batch type or continuous roast apparatus.
Claims24
Coffee bean processing comprising:
- a. housing means forming at least one processing chamber for a quantity of coffee beans undergoing processing, said housing means having air inlet means at the bottom of said chamber connected to blower means for creating a controlled updraft through said air inlet means in a first vertically extending updraft portion of said chamber, said housing means including interior wall means joined to said air inlet means, at least one part of said wall means diverging upwardly away from said air inlet means at an acute angle, another part of said wall means forming a second vertically extending downdraft portion of said chamber adjacent said updraft portion;
- b. said blower means for collecting ambient air and forcing it through said air inlet means with sufficient velocity to provide said controlled updraft so that said updraft levitates said coffee beans upwardly in said first vertically extending portion of said chamber and outwardly into said second vertically extending downdraft portion wherein said beans move downwardly to enter said first portion so that said quantity of coffee beans forms a dense recirculating fluidized mass;
- and
- c. heater means for heating said collected air before entry into said chamber as said controlled updraft to a predetermined coffee bean processing temperature, said heater means including limiting means for providing said heated air updraft with a temperature not in excess of 530.degree. F.,
- whereby heat is transferred into the beans by convection from said heated updraft and by thermal conduction from bean to bean throughout the dense recirculating fluidized coffee bean mass to provide thermal equilibrium and a uniform roast.
2 more elements
A coffee bean roaster comprising:
- a. a roasting chamber formed by a wide shallow rectangular base plate with a multiplicity of spaced apart orifices therein, a front wall meeting said plate at an acute angle and extending upwardly therefrom, a back wall extending upwardly from said plate and diverging away from said front wall and side walls extending upwardly from said plate and joined to said front wall and said back wall;
- b. a plenum connected to said chamber and communicating with said base plate;
- c. a blower in said plenum and adapted to collect air and force it through said orifices with sufficient velocity to levitate a charge of coffee beans in said chamber in a dense, recirculating fluidized mass of beans;
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- d. a heater element in said plenum and adapted to heat said collected air to a predetermined coffee bean roasting temperature not greater than 530.degree. F., before said air is forced through said orifices.
2 more elements
Coffee bean processing apparatus comprising:
- a. housing means forming at least one processing chamber for holding a quantity of coffee beans, said chamber having means for defining an undraft portion and a recirculation portion, said housing means connected to blower means and containing airstream directing means creating a controlled updraft in said updraft portion of said chamber;
- b. said blower means to collect ambient air and force it into said chamber through said airstream directing means with sufficient velocity so that said updraft lifts coffee beans in said updraft portion of said chamber to move said quantity of coffee beans into said recirculation portion as a dense, recirculating fluidized mass;
- and
- c. heater means for heating said collected air before entry into said chamber as said controlled updraft to a predetermined coffee bean processing temperature, said heater means including limiting means for providing said heated air updraft with a temperature not in excess of 530.degree. F;
- d. coffee bean temperature sensor means positioned within said chamber in said recirculation portion and completely outside of said controlled updraft portion, said sensor means for contacting said dense recirculating mass of coffee beans and operable for sensing the occurrence of pyrolitically induced thermal rise in said quantity of coffee beans undergoing heating;
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- e. temperature indicator means connected to said temperature sensor means and operable for indicating measured virtual coffee bean temperature in said chamber and the occurrence of pyrolitically induced thermal rise in said quantity of heated coffee beans.
4 more elements
Dependencies are inferred from the claim text.