Dehydrator apparatus with unidirectional air flow control means

Claim 2

Dehydrator apparatus for drying food comprising: a housing including a vertical sidewall portion and a transverse base wall joined to said sidewall portion and forming an enclosure; air intake means in said housing comprising a plurality of spaced apart recesses formed by respective wall portions of said housing projecting inwardly from said sidewall portion adjacent said base wall and forming air inlet flow channels into said housing through openings in respective walls of said recesses; at least one food supporting tray member disposed across an open top part of said housing, said tray member having a foraminous food supporting portion forming a generally flat shelf; a fan mounted in said housing generally above said openings and disposed for inducting a flow of air into said housing through said air intake means and then through said shelf; and a motor mounted in said housing below and drivably connected to said fan, said motor being mounted adjacent said openings in said recesses whereby air is drawn through said channels into said housing by said fan and flows generally over said motor before flowing through said shelf.

Claim 3

The invention set forth in claim 1 together with: an electrical heating element mounted in the flow path of said air flow through said housing.

Claim 4

The invention set forth in claim 2 wherein: said heating element includes a shield disposed between said heating element and said tray member.

Claim 5

The invention set forth in claim 1 wherein: said wall portions forming said recesses are adapted to support said motor and said heating element.

Claim 6

The invention set forth in claim 1 wherein: said shelf includes a plurality of orifices defined by wall means converging in the direction of air flow propelled by said fan, said orifices presenting a resistance to air flow in the opposite direction greater than the resistance to air flow in the direction propelled by said fan.

Claim 7

The invention set forth in claim 5 wherein: said tray member is generally circular and said orifices are formed as annular concentric rows of openings in said shelf.

Claim 8

The invention set forth in claim 5 wherein: said apparatus includes a plurality of tray members vertically stackable one on top of another to provide a plurality of spaced apart food drying levels, each of said tray members being provided with orifices in said shelf adapted to provide for substantially vertical unidirectional air flow from the space above one drying level to the space above the next drying level.

Claim 9

The invention set forth in claim 7 wherein: said tray members are circular and are provided with circular peripheral axially extending rim and flange portions, said rim portions engageable in nesting relationship within the flange of the adjacent tray member.

Claim 10

The invention set forth in claim 5 wherein: said orifices are formed by substantially flat sided converging wall portions forming a pyramidal shaped flow passage defining an outlet opening of smaller cross sectional flow area than an inlet opening to said flow passage.

Claim 11

The invention set forth in claim 9 wherein: said converging wall portions form an angle with respect to the longitudinal axis of said flow passage of at least 15 degrees.

Claim 12

Dehydrator apparatus for drying food, comprising: housing means forming an enclosure having air intake means and air discharge means; fan means for directing a flow of air through said housing means; and food supporting tray means adapted to be supported by said housing and comprising a foraminous shelf disposed in the flow path of air passing through said housing means, said shelf including means providing a food supporting surface, a plurality of openings in said shelf forming a plurality of flow passages defined by wall means converging toward and intersecting said means forming said food supporting surface and in the direction of air flow propelled by said fan means, said openings in said shelf providing a greater resistance to air flow in a direction opposite to the direction of air flow provided by said fan means whereby recirculation of drying air through said dehydrator is minimized.

Claim 13

Dehydrator apparatus for drying food, comprising: housing means forming an enclosure having air intake means and air discharge means; fan means for directing a flow of air through said housing means; and food supporting tray means adapted to be supported by said housing and comprising a foraminous shelf disposed in the flow path of air passing through said housing means, said shelf including means providing a food supporting surface, a plurality of openings in said shelf forming a plurality of flow passages defined by wall means converging toward and intersecting said means forming said food supporting surface and in the direction of air flow propelled by said fan means, said openings in said shelf providing a greater resistance to air flow in a direction opposite to the direction of air flow provided by said fan means whereby recirculation of drying air through said dehydrator is minimized.

Claim 14

Dehydrator apparatus for drying food, comprising: housing means forming an enclosure having air intake means and air discharge means; fan means for directing a flow of air through said housing means; a plurality of food supporting trays supported on said housing vertically stacked one on top of another to provide a plurality of spaced apart drying levels disposed in the flow path of air passing through said housing means, each of said trays being provided with openings therein of a configuration which provide for flow of air generally in one direction through the spaces between said plurality of drying levels, said openings in said trays being formed to provide a greater resistance to air flow in a direction opposite to said one direction whereby recirculation of drying air between said drying levels is minimized.

Claim 15

Dehydrator apparatus for drying food, comprising: housing means forming an enclosure having air intake means and air discharge means; fan means for directing a flow of air through said housing means; a plurality of food supporting trays supported on said housing vertically stacked one on top of another to provide a plurality of spaced apart drying levels disposed in the flow path of air passing through said housing means, each of said trays being provided with openings therein of a configuration which provide for flow of air generally in one direction through the spaces between said plurality of drying levels, said openings in said trays being formed to provide a greater resistance to air flow in a direction opposite to said one direction whereby recirculation of drying air between said drying levels is minimized.

Claim 16

The invention set forth in claim 12 wherein: said trays are circular and are provided with circular peripheral axially extending rim and flange portions, said rim portions engageable in nesting relationship within the flange portion of the adjacent tray.

Claim 17

The invention set forth in claim 12 wherein: said openings are formed by substantially flat sided converging wall portions forming a pyramidal shaped flow passage defining an outlet opening of smaller cross sectional flow area than an inlet opening to said flow passage.

Claim 18

The invention set forth in claim 14 wherein: said converging wall portions form an angle with respect to the longitudinal axis of said flow passage of at least 15 degrees.

Claim 19

Dehydrator apparatus for drying food comprising: a generally cylindrical vertically disposed tubular housing forming an enclosure with air intake means formed at the bottom of said housing; a fan mounted in said housing and disposed for inducting a flow of air into said housing through said air intake means; a motor mounted in said housing and drivably connected to said fan; a foraminous shelf disposed across the interior of said housing above said fan; and a plurality of food supporting trays vertically stackable one on top of another on said housing above said shelf to provide a plurality of spaced apart food drying levels, said shelf and said plurality of trays each being provided with a plurality of orifices defined by wall means converging generally in the direction of air flow propelled by said fan, said orifices in said shelf and said trays providing a resistance to air flow in a direction opposite to the direction of flow propelled by said fan greater than the resistance to flow in the direction which air is being propelled by said fan.

Claim 20

Dehydrator apparatus for drying food comprising: a generally cylindrical vertically disposed tubular housing forming an enclosure with air intake means formed at the bottom of said housing; a fan mounted in said housing and disposed for inducting a flow of air into said housing through said air intake means; a motor mounted in said housing and drivably connected to said fan; a foraminous shelf disposed across the interior of said housing above said fan; and a plurality of food supporting trays vertically stackable one on top of another on said housing above said shelf to provide a plurality of spaced apart food drying levels, said shelf and said plurality of trays each being provided with a plurality of orifices defined by wall means converging generally in the direction of air flow propelled by said fan, said orifices in said shelf and said trays providing a resistance to air flow in a direction opposite to the direction of flow propelled by said fan greater than the resistance to flow in the direction which air is being propelled by said fan.

Claim 21

A cylindrical tray for supporting material such as food particles and the like for dehydration, said tray comprising a member adapted to be positioned in the path of a flow of air through a duct or the like, said member being formed with peripheral rim and flange portions extending axially in opposite directions from a foraminous wall, said wall including a plurality of flow passages therein extending from one surface of said wall to an opposed surface of said wall, said passages converging from said one surface to intersection with said opposed surface of said wall, said passages being formed by substantially flat sided converging portions of said wall forming pyramidal shaped flow passages defining outlet openings in the plane of said opposed surface of smaller cross-sectional flow area than the inlet openings of said passages formed in the plane of said other surface, said converging wall portions forming an angle with respect to the longitudinal axis of said passages of at least 15 degrees, said member being arranged with respect to the flow of air through said duct whereby the normal direction of flow is in the direction of convergency of said passages whereby the resistance to air flow through said duct due to said member in the direction of convergency of said passages is less than the resistance to air flow in the opposite direction.

Claim 22

A cylindrical tray for supporting material such as food particles and the like for dehydration, said tray comprising a member adapted to be positioned in the path of a flow of air through a duct or the like, said member being formed with peripheral rim and flange portions extending axially in opposite directions from a foraminous wall, said wall including a plurality of flow passages therein extending from one surface of said wall to an opposed surface of said wall, said passages converging from said one surface to intersection with said opposed surface of said wall, said passages being formed by substantially flat sided converging portions of said wall forming pyramidal shaped flow passages defining outlet openings in the plane of said opposed surface of smaller cross-sectional flow area than the inlet openings of said passages formed in the plane of said other surface, said converging wall portions forming an angle with respect to the longitudinal axis of said passages of at least 15 degrees, said member being arranged with respect to the flow of air through said duct whereby the normal direction of flow is in the direction of convergency of said passages whereby the resistance to air flow through said duct due to said member in the direction of convergency of said passages is less than the resistance to air flow in the opposite direction.