Apparatus and method for removing fumes from the space above a cooking appliance

Claim 3

The invention as claimed in claim 1, in which said method further comprises employing as said grease filter a filter having an inner face which lies generally in a single plane, and causing said stream of supply air to initially strike said inner face while traveling in a direction generally perpendicular to such face.

Claim 4

The invention as claimed in claim 1, in which said method further comprises employing as said grease filter a filter having an inner face which lies in a single plane, causing said stream of supply air to initially strike said inner face while traveling in a direction generally perpendicular to such face, and causing said stream of supply air to initially strike said inner face at an intermediate elevation lower than the upper edge portion of said filter and higher than the lower edge portion thereof.

Claim 5

The invention as claimed in claim 1, in which said method further comprises preventing any substantial amount of said supply air from passing out of said hood and into said room.

Claim 6

The invention as claimed in claim 1, in which said method further comprises causing the vortex of said upwardly rolled supply air to be large in size, and causing the vortex of said downwardly rolled supply air to be small in size.

Claim 7

The invention as claimed in claim 1, in which said method further comprises causing the average velocity of said stream of supply air, at the region where such stream enters the portion of said hood which first receives fumes from said cooking appliance, to be in the range of about 1,000 fpm to about 1,500 fpm.

Claim 8

The invention as claimed in claim 1, in which said method further compriseS employing as said grease filter an impingement-type filter, and causing the velocity of air and fumes passing through said filter to be in the range of about 300 fpm to about 900 fpm.

Claim 9

The invention as claimed in claim 1, in which said method further comprises causing the average velocity of said stream of supply air, at the region where such stream enters the portion of said hood which first receives fumes from said cooking appliance, to be much higher than the velocity of the air and fumes passing through said filter.

Claim 10

The invention as claimed in claim 1, in which said method further comprises directing said stream of said supply air through said hood in an upward direction at an incline to the horizontal and into engagement with said filter, and causing said stream of supply air to first strike the inner face of said filter while traveling in a direction substantially perpendicular to such inner face.

Claim 11

The invention as claimed in claim 1, in which said method further comprises so balancing said supply blower relative to said exhaust blower that the number of cfm of air supplied to said hood from said region exterior to said room is less than, but not over a few hundred cfm less than, the number of cfm of air and fumes which pass through said filter.

Claim 12

The invention as claimed in claim 1, in which said method further comprises so balancing said supply blower relative to said exhaust blower that the number of cfm of air supplied to said hood from said region exterior to said room is about 100 cfm less than the number of cfm of air and fumes which pass through said filter.

Claim 13

The invention as claimed in claim 1, in which said method further comprises effecting said directing of said stream of supply air by means including a baffle disposed in the lower portion of said hood, and additionally passing part of said supply air into the region beneath said baffle and in a direction toward said filter.

Claim 14

The invention as claimed in claim 1, upwardly off which said method further comprises employing as said grease filter a filter having an inner face which lies in a single plane, causing said stream of supply air to initially strike said inner face while traveling in a direction generally perpendicular to such face, and causing said stream of supply air to initially strike said inner face at at an intermediate elevation lower than the upper edge portion of said filter and higher than the lower edge portion thereof, in which said method further comprises causing the vortex of supply air which rolls upwardly off said filter to be large in size, and causing the vortex of supply air which rolls downwardly off said filter to be small in size, and in which said method further comprises preventing any substantial amount of said supply air from passing out of said hood and into said room.

Claim 15

The invention as claimed in claim 13, in which said method further comprises causing the average velocity of said stream of supply air, at the region where such stream enters the portion of said hood which first receives fumes from said cooking appliance, to be in the range of about 1,000 fpm to about 1,500 fpm, and in which said method further comprises employing as said grease filter an impingement-type filter, and causing the velocity of air and fumes passing through said filter to be in the range of about 300 fpm to about 900 fpm.

Claim 16

A fume hood or canopy adapted to be mounted in a room in spaced relationship above a cooking appliance, which comprises: a housing defining an open-bottomed capture and entrainment chamber adapted to receive fumes from said cooking appliance, grease filter means mounted in said housing and exposed to said capture and entrainment chamber, exhaust conduit and blower means to draw exhaust air and fumes through said filter means from said capture and entrainment chamber for discharge to a region exterior to said room, supply conduit and blower means connected directlY to said housing to pump supply air directly to said housing from a region exterior to said room, director means to direct at least the major part of said supply air in a stream through said capture and entrainment chamber to said filter means, without leaving said housing, said director means being related to said capture and entrainment chamber, to said filter means, and to said housing in such manner that said stream strikes said filter means and then divides into three portions, the first of such stream portions passing directly through said filter means to said exhaust conduit and blower means, the second of such stream portions rolling upwardly, and the third of such stream portions rolling downwardly, first deflector means to deflect said second stream portion back to said filter means for passage therethrough to said exhaust conduit and blower means, and second deflector means to deflect said third stream portion back to said filter means for passage therethrough to said exhaust conduit and blower means, whereby fumes which pass upwardly from said cooking appliance into said capture and entrainment chamber are effectively withdrawn through said filter means and discharged by said exhaust conduit and blower means.

Claim 17

A fume hood or canopy adapted to be mounted in a room in spaced relationship above a cooking appliance, which comprises: a housing defining an open-bottomed capture and entrainment chamber adapted to receive fumes from said cooking appliance, grease filter means mounted in said housing and exposed to said capture and entrainment chamber, exhaust conduit and blower means to draw exhaust air and fumes through said filter means from said capture and entrainment chamber for discharge to a region exterior to said room, supply conduit and blower means connected directlY to said housing to pump supply air directly to said housing from a region exterior to said room, director means to direct at least the major part of said supply air in a stream through said capture and entrainment chamber to said filter means, without leaving said housing, said director means being related to said capture and entrainment chamber, to said filter means, and to said housing in such manner that said stream strikes said filter means and then divides into three portions, the first of such stream portions passing directly through said filter means to said exhaust conduit and blower means, the second of such stream portions rolling upwardly, and the third of such stream portions rolling downwardly, first deflector means to deflect said second stream portion back to said filter means for passage therethrough to said exhaust conduit and blower means, and second deflector means to deflect said third stream portion back to said filter means for passage therethrough to said exhaust conduit and blower means, whereby fumes which pass upwardly from said cooking appliance into said capture and entrainment chamber are effectively withdrawn through said filter means and discharged by said exhaust conduit and blower means.

Claim 18

The invention as claimed in claim 15, in which the face of said filter means which is exposed to said capture and entrainment chamber is substantially planar, and in which said director means is so related to said face that said stream when passing through said capture and entrainment chamber from said director means to said face is substantially perpendicular to said face.

Claim 19

The invention as claimed in claim 15, in which the face of said filter means which is exposed to said capture and entrainment chamber lies in an inclined plane and faces downwardly, and in which said director means passes said stream upwardly at an incline and directly into engagement with said face substantially perpendicularly thereto.

Claim 20

The invention as claimed in claim 15, in which the supply blower means is balanced relative to the exhaust blower means in such manner that the number of cfm of exhaust air and fumes which pass through said filter means from said capture and entrainment chamber is greater than, but not over a few hundred cfm greater than, the number of cfm of supply air delivered to said capture and entrainment chamber by said supply conduit and blower means.

Claim 21

The invention as claimed in claim 15, in which said second deflector means includes a baffle plate which deflects fumes from said cooking appliance upwardly into the region adjacent said filter means, the entire lower surface of said baffle plate being inclined at a large angle relative to the horizontal.

Claim 22

The invention as claimed in claim 15, in which means are provided to pass a portion of said supply air downwardly from said supply conduit and blower means to the region immediately beneath said director means, and to cause such portion to flow beneath said director means toward said capture and entrainment chamber whereby to entrain fumes which pass upwardly from said cooking appliance into said region beneath said director means.

Claim 23

The invention as claimed in claim 16, in which means are provided to pass a portion of said supply air downwardly to the region immediately beneath said director means, and to cause such portion to flow beneath said director means toward said capture and entrainment chamber whereby to entrain fumes which pass upwardly from said cooking appliance into said region beneath said director means, in which said face lies in an inclined plane, and in which said director means is so related to said face that said stream initially strikes said face at an intermediate elevation below that of the upper edge of said face, and above that of the lower edge of said face.

Claim 24

A self-contained fume hood adapted to be mounted in a room over a cooking appliance, which comprises: a rigid rectangular housing having a fRont wall, a rear wall, and parallel side walls, means to define a capture and entrainment chamber in said housing, the portion of said housing beneath said chamber being open whereby to permit convection of fumes upwardly from said cooking appliance into said chamber, a grease filter mounted in said housing remote from said front wall thereof and exposed to said chamber, exhaust conduit and blower means to draw air and fumes through said filter from said chamber and to exhaust said air and fumes to a region exterior to the room in which said housing is mounted, supply conduit and blower means to pump supply air from a region exterior to said room to a portion of said housing exterior to said chamber and adjacent the upper region of said front wall of said housing, means provided in said housing to direct said supply air downwardly from said housing portion, wall means provided in said housing to define the upper region of a generally horizontal throat, a baffle plate disposed in said housing in spaced relationship below said wall means and transverse to the downwardly flowing supply air, said baffle plate defining the lower region of said horizontal throat, said baffle plate and said wall means cooperating with each other to cause said supply air to enter said capture and entrainment chamber in relatively laminar manner for flow to said filter, hinge means provided relatively adjacent said front wall of said housing to effect pivotal mounting of the forward edge of said baffle plate, means to effect vertical adjustment of said hinge means whereby to raise and lower said forward edge of said baffle plate, and means to pivot said baffle plate upwardly and downwardly relative to said hinge means, said means for vertically adjusting said forward edge of said baffle plate, and said pivot means, cooperating to change the cross-sectional area of said horizontal throat, and also cooperating to change the direction at which said supply air enters said capture and entrainment chamber.

Claim 25

A self-contained fume hood adapted to be mounted in a room over a cooking appliance, which comprises: a rigid rectangular housing having a fRont wall, a rear wall, and parallel side walls, means to define a capture and entrainment chamber in said housing, the portion of said housing beneath said chamber being open whereby to permit convection of fumes upwardly from said cooking appliance into said chamber, a grease filter mounted in said housing remote from said front wall thereof and exposed to said chamber, exhaust conduit and blower means to draw air and fumes through said filter from said chamber and to exhaust said air and fumes to a region exterior to the room in which said housing is mounted, supply conduit and blower means to pump supply air from a region exterior to said room to a portion of said housing exterior to said chamber and adjacent the upper region of said front wall of said housing, means provided in said housing to direct said supply air downwardly from said housing portion, wall means provided in said housing to define the upper region of a generally horizontal throat, a baffle plate disposed in said housing in spaced relationship below said wall means and transverse to the downwardly flowing supply air, said baffle plate defining the lower region of said horizontal throat, said baffle plate and said wall means cooperating with each other to cause said supply air to enter said capture and entrainment chamber in relatively laminar manner for flow to said filter, hinge means provided relatively adjacent said front wall of said housing to effect pivotal mounting of the forward edge of said baffle plate, means to effect vertical adjustment of said hinge means whereby to raise and lower said forward edge of said baffle plate, and means to pivot said baffle plate upwardly and downwardly relative to said hinge means, said means for vertically adjusting said forward edge of said baffle plate, and said pivot means, cooperating to change the cross-sectional area of said horizontal throat, and also cooperating to change the direction at which said supply air enters said capture and entrainment chamber.

Claim 26

The invention as claimed in claim 22 in which said baffle plate comprises first and second overlapping parallel plate portions, and means to secure such plate portions together with different degrees of overlapping whereby to change the effective dimension of said baffle plate in a direction perpendicular to said front wall of said housing.

Claim 27

The invention as claimed in claim 22, in which said means to vertically adjust said hinge means comprises upwardly extending fastener means threadedly associated with a fixed support, and in which said means to pivot said baffle plate comprises an upwardly extending member threadedly associated with a fixed support, and means to provide a universal connection between said last-mentioned member and said baffle plate.

Claim 28

The invention as claimed in claim 22, in which ledge means are provided on said housing beneath said baffle plate and adjacent said rear wall of said housing, said ledge means projecting rearwardly toward said capture and entrainment chamber, and in which passage means are provided between said rear housing wall and said forward edge of said baffle plate whereby to permit a portion of the supply air to pass downwardly through said passage means into engagement with said ledge means, such supply air portion then being deflected by said ledge means forwardly and beneath said baffle plate into said capture and entrainment chamber, thus entraining fumes which pass upwardly into the region of said housing beneath said baffle plate and causing such fumes to enter said capture and entrainment chamber.

Claim 29

The invention as claimed in claim 22 in which an upwardly inclined lip is provided on the rear edge of said baffle plate.

Claim 30

The invention as claimed in claim 22, in which ledge means are provided on said housing beneath said baffle plate and adjacent said rear wall of said housing, said ledge means projecting rearwardly toward said capture and entrainment chamber, and in which passage means are provided between said rear housing wall and said forward edge of said baffle plate whereby to permit a portion of the supply air to pass downwardly through said passage means into engagement with said ledge means, such supply air portion then being deflected by said ledge means forwardly and beneath said baffle plate into said capture and entrainment chamber, in which additional ledge means are provided on said housing below the ends of said baffle plate, and in which additional passage means are provided between said baffle ends and said side walls of said housing, whereby other portions of the supply air may pass downwardly through said last-mentioned passage means for deflection by said last-mentioned ledge means in directions away from said side walls, and for subsequent entrainment in said first-mentioned supply air portion.

Claim 31

The invention as claimed in claim 22, in which said upper region of said horizontal throat, and said baffle plate, are so constructed and adjusted that the supply air entering said capture and entrainment chamber from said horizontal throat passes through said capture and entrainment chamber in an upwardly inclined direction, and in which said filter is substantially perpendicular to such upwardly inclined direction whereby said supply air strikes said filter substantially perpendicularly.

Claim 32

A fume hood adapted to be mounted in a room above a cooking appliance therein, which comprises: an open-bottomed rectangular housing having parallel front and rear walls and parallel side walls, said housing incorporating means to define an open-bottomed capture and entrainment chamber adapted to receive fumes passing upwardly from said cooking appliance, said last-named means to define said chamber including a grease filter lying in an inclined plane, means to supply air to said housing from a region exterior to said room and to direct at least a major portion of such supply air through said capture and entrainment chamber toward said filter in an upwardly inclined stream or curtain, means to draw air and fumes through said filter from said capture and entrainment chamber and to exhaust such air and fumes to a region exterior to said room, a lower deflector disposed beneath the lower edge of said filter, and an inclined deflector plate extending from a region adjacent said rear wall of said housing to a region above said lower deflector, said inclined deflector plate being inclined at a very substantial angle to the horizontal and serving to deflect upwardly and into the vicinity of said filter the fumes which pass upwardly into the region of said housing relatively adjacent said rear wall thereof.

Claim 33

A fume hood adapted to be mounted in a room above a cooking appliance therein, which comprises: an open-bottomed rectangular housing having parallel front and rear walls and parallel side walls, said housing incorporating means to define an open-bottomed capture and entrainment chamber adapted to receive fumes passing upwardly from said cooking appliance, said last-named means to define said chamber including a grease filter lying in an inclined plane, means to supply air to said housing from a region exterior to said room and to direct at least a major portion of such supply air through said capture and entrainment chamber toward said filter in an upwardly inclined stream or curtain, means to draw air and fumes through said filter from said capture and entrainment chamber and to exhaust such air and fumes to a region exterior to said room, a lower deflector disposed beneath the lower edge of said filter, and an inclined deflector plate extending from a region adjacent said rear wall of said housing to a region above said lower deflector, said inclined deflector plate being inclined at a very substantial angle to the horizontal and serving to deflect upwardly and into the vicinity of said filter the fumes which pass upwardly into the region of said housing relatively adjacent said rear wall thereof.

Claim 34

The invention as claimed in claim 29, in which said inclined deflector plate has an upper edge portion which engages the forward edge of said lower deflector and cooperates therewith in deflecting upwardly to said filter air and fumes which roll downwardly therefrom.

Claim 35

The invention as claimed in claim 29, in which said lower deflector is a generally horizontal flange which extends rearwardly from an inclined liner lying in generally the same plane as said filter and extending downwardly therefrom, and in which said deflector plate lies at approximately a 45* angle from the horizontal.

Claim 36

The invention as claimed in claim 29, in which said lower deflector extends outwardly from a liner which lies in generally the same plane as said filter and extends downwardly therefrom, and in which exposed groove means are provided in said liner to receive grease which drips downwardly from said filter, said groove means being inclined and communicating with catch means for said grease.

Claim 37

The invention as claimed in claim 32, in which means are provided to heat said groove means to maintain in liquid condition the grease therein.

Claim 38

A fume hood for mounting in a room above a cooking appliance disposed in such room, which comprises: a housing adapted to be mOunted in said room above a cooking appliance therein, said housing having formed therein an open-bottomed capture and entrainment chamber adapted to receive fumes passing upwardly from said cooking appliance, filter means exposed to said capture and entrainment chamber and adapted to filter grease, exhaust blower means to draw through said filter means air and fumes from said chamber, and to discharge said air and fumes to a region exterior to said room, supply blower means connected to said housing to supply air from a region exterior to said room to a portion of said housing outside said chamber, first inlet means to conduct supply air from said housing portion to said chamber for flow therethrough to said filter means, and second inlet means to pass a portion of said supply air from said housing portion to the vicinity of the bottom of said housing and below said first inlet means, and to direct such supply-air portion toward said chamber for flow therethrough to said filter means, said second inlet means serving to entrain fumes which pass to the region below said first inlet means and to cause such entrained fumes to enter said chamber.

Claim 39

A fume hood for mounting in a room above a cooking appliance disposed in such room, which comprises: a housing adapted to be mOunted in said room above a cooking appliance therein, said housing having formed therein an open-bottomed capture and entrainment chamber adapted to receive fumes passing upwardly from said cooking appliance, filter means exposed to said capture and entrainment chamber and adapted to filter grease, exhaust blower means to draw through said filter means air and fumes from said chamber, and to discharge said air and fumes to a region exterior to said room, supply blower means connected to said housing to supply air from a region exterior to said room to a portion of said housing outside said chamber, first inlet means to conduct supply air from said housing portion to said chamber for flow therethrough to said filter means, and second inlet means to pass a portion of said supply air from said housing portion to the vicinity of the bottom of said housing and below said first inlet means, and to direct such supply-air portion toward said chamber for flow therethrough to said filter means, said second inlet means serving to entrain fumes which pass to the region below said first inlet means and to cause such entrained fumes to enter said chamber.

Claim 40

The invention as claimed in claim 34, in which said first inlet means includes a horizontally elongated plate extending from the vicinity of a front wall of said housing toward a rear wall of said housing, and in which said second inlet means effects flow of said supply-air portion below said plate and generally parallel thereto toward said chamber.

Claim 41

The invention as claimed in claim 35, in which gaps are provided around the edges of said plate, said gaps forming said second inlet means, and in which inwardly extending ledge means are provided around the lower region of said housing, said ledge means serving to deflect inwardly and toward said capture and entrainment chamber the air which passes downwardly through said gaps.

Claim 42

The invention as claimed in claim 34, in which said second inlet means includes ledge means which extend inwardly from the lower portion of said housing, said ledge means having an upper surface adapted to deflect air toward said capture and entrainment chamber and also adapted to receive condensate, said ledge means communicating with a catch means for said condensate.

Claim 43

A fume hood for mounting in a room over a cooking appliance therein, which comprises: a housing defining an open-bottomed capture and entrainment chamber, a grease filter mounted in said housing and exposed to said chamber, blower means to draw air and fumes through said filter from said chamber and to discharge such air and fumes to a region exterior to said room, blower means to supply air to said housing from a region exterior to said room and to direct such air through said chamber to said filter, an inclined liner mounted in said housing below said filter and exposed to said chamber, the upper edge of said liner being close to the exposed face of said filter whereby grease from said filter drips along the exposed face of said liner, exposed groove means provided at said liner to receive grease which flows downwardly along the exposed face thereof, said groove means being at an incline to the horizontal whereby grease therein will flow downwardly into a suitable catch means, and heating means provided on the side of said liner remote from said chamber, said heating means serving to maintain the grease in said groove means warm despite the continuous passage of supply air through said chamber to said filter.

Claim 44

A fume hood for mounting in a room over a cooking appliance therein, which comprises: a housing defining an open-bottomed capture and entrainment chamber, a grease filter mounted in said housing and exposed to said chamber, blower means to draw air and fumes through said filter from said chamber and to discharge such air and fumes to a region exterior to said room, blower means to supply air to said housing from a region exterior to said room and to direct such air through said chamber to said filter, an inclined liner mounted in said housing below said filter and exposed to said chamber, the upper edge of said liner being close to the exposed face of said filter whereby grease from said filter drips along the exposed face of said liner, exposed groove means provided at said liner to receive grease which flows downwardly along the exposed face thereof, said groove means being at an incline to the horizontal whereby grease therein will flow downwardly into a suitable catch means, and heating means provided on the side of said liner remote from said chamber, said heating means serving to maintain the grease in said groove means warm despite the continuous passage of supply air through said chamber to said filter.

Claim 45

A fume hood or canopy for mounting in a room above a cooking appliance therein, which comprises: wall means to define a generally rectangular housing having an open bottom, said housing having generally parallel front and rear walls and generally parallel side walls, a front liner provided in said housing and lying in an inclined plane, said front liner extending for the entire distance between said side waLls, a rear liner mounted in said housing and extending downwardly at an incline from the upper edge of said front liner, said rear liner extending the entire distance between said side walls, said front and rear liners being transverse to each other, a planar filter means mounted in said rear liner and adapted to filter grease, said filter means extending substantially the entire distance between said side walls, the upper edge of said filter means being spaced from the intersection between said rear and front liners, the lower edge of said filter means being spaced from the lower edge of said rear liner, said rear and front liners, and said filter means, cooperating with the side walls of said housing to define an open-bottomed capture and entrainment chamber adapted to receive fumes from said cooking appliance, blower and exhaust means to draw air through said filter means from said capture and entrainment chamber and to discharge such air to a region exterior to said room, supply conduit and blower means to supply air from a region exterior to said room to the region of said housing between said front liner and said front wall of said housing, vertical throat means to conduct supply air downwardly from said last-mentioned housing region to the vicinity of the lower portion of said housing, generally horizontal throat means to receive such supply air and to direct the same into said capture and entrainment chamber in a generally laminar stream or curtain, said horizontal throat means being so directed that said stream or curtain passes directly through said capture and entrainment chamber, in an upward and rearward direction, and strikes said filter means generally perpendicularly thereto, whereby a portion of said supply air which strikes said filter means rolls or vortexes upwardly into engagement with said front liner and then back downwardly for flow through said filter means, and whereby another portion of said supply air which strikes said filter means rolls or vortexes downwardly, and lower deflector means provided in said housing below said filter means to deflect said last-mentioned air upwardly to said filter means.

Claim 46

A fume hood or canopy for mounting in a room above a cooking appliance therein, which comprises: wall means to define a generally rectangular housing having an open bottom, said housing having generally parallel front and rear walls and generally parallel side walls, a front liner provided in said housing and lying in an inclined plane, said front liner extending for the entire distance between said side waLls, a rear liner mounted in said housing and extending downwardly at an incline from the upper edge of said front liner, said rear liner extending the entire distance between said side walls, said front and rear liners being transverse to each other, a planar filter means mounted in said rear liner and adapted to filter grease, said filter means extending substantially the entire distance between said side walls, the upper edge of said filter means being spaced from the intersection between said rear and front liners, the lower edge of said filter means being spaced from the lower edge of said rear liner, said rear and front liners, and said filter means, cooperating with the side walls of said housing to define an open-bottomed capture and entrainment chamber adapted to receive fumes from said cooking appliance, blower and exhaust means to draw air through said filter means from said capture and entrainment chamber and to discharge such air to a region exterior to said room, supply conduit and blower means to supply air from a region exterior to said room to the region of said housing between said front liner and said front wall of said housing, vertical throat means to conduct supply air downwardly from said last-mentioned housing region to the vicinity of the lower portion of said housing, generally horizontal throat means to receive such supply air and to direct the same into said capture and entrainment chamber in a generally laminar stream or curtain, said horizontal throat means being so directed that said stream or curtain passes directly through said capture and entrainment chamber, in an upward and rearward direction, and strikes said filter means generally perpendicularly thereto, whereby a portion of said supply air which strikes said filter means rolls or vortexes upwardly into engagement with said front liner and then back downwardly for flow through said filter means, and whereby another portion of said supply air which strikes said filter means rolls or vortexes downwardly, and lower deflector means provided in said housing below said filter means to deflect said last-mentioned air upwardly to said filter means.

Claim 47

The invention as claimed in claim 39, in which said horizontal throat means includes a lower baffle plate which extends for substantially the entire distance between said side walls, and in which means are provided to effect substantially independent horizontal, vertical and pivotal adjustments of said baffle plate.

Claim 48

The invention as claimed in claim 39, in which means are provided to pass a portion of said supply air downwardly into the region below said horizontal throat means, and to effect flow of such air rearwardly beneath said horizontal throat means and into said capture and entrainment chamber, such air serving to entrain fumes which pass upwardly to a region below said horizontal throat means.

Claim 49

The invention as claimed in claim 39, in which a steeply inclined baffle is provide beneath said lower deflector means and extends downwardly at an incline to the vicinity of the rear wall of said housing, said baffle deflecting upwardly into said capture and entrainment chamber fumes which pass upwardly and relatively adjacent said rear wall.

Claim 50

The invention as claimed in claim 39, in which said horizontal throat means is so located and directed that said stream or curtain strikes said filter means at an intermediate elevation spaced downwardly from the upper edge of said filter means, and spaced upwardly from the lower edge thereof, and in which said supply conduit and blower means is adapted to effect laminar flow of air into said housing region formed between said front liner and the front wall of said housing.

Claim 51

The invention as claimed in claim 39, in which the area of said filter means is much greater than the cross-sectional area of said horizontal throat means.

Claim 52

A fume hood or canopy for mounting in a room above a cooking appliance therein, which comprises wall means to define a generally rectangular housing having an open bottom, said housing having generally parallel front and rear walls and generally parallel side walls, a front liner provided in said housing and lying in an inclined plane, a rear liner mounted in said housing and extending downwardly at an incline from the upper edge of said front liner, said front and rear liners being transverse to each other, a planar filter means mounted in said rear liner and adapted to filter grease, said rear and front liners, and said filter means, cooperating with the side walls of said housing to define an open-bottomed capture and entrainment chamber adapted to receive fumes from said cooking appliance, blower and exhaust means to draw air through said filter means from said capture and entrainment chamber and to discharge such air to a region exterior to said room, supply conduit and blower means to supply air from a region exterior to said room to the region of said housing between said front liner and said front wall of said housing, vertical throat means to conduct supply air downwardly from said last-mentioned housing region to the vicinity of the lower portion of said housing, said vertical throat means being defined in part by a generally vertical plate which extends downwardly from said front liner, and generally horizontal throat means to receive such supply air and to direct the same into said capture and entrainment chamber in a generally laminar stream or curtain, said horizontal throat means being so directed that said stream or curtain passes directly through said capture and entrainment chamber, in an upward and rearward direction, and strikes said filter means, whereby a portion of said supply air which strikes said filter means rolls upwardly into engagement with said front liner, then flows forwardly down said front liner, then passes downwardly along said vertical plate, and then passes rearwardly across said capture and entrainment chamber back to said filter means, said flow of said portion of supply air constituting a very large-diameter vortex.

Claim 53

A fume hood or canopy for mounting in a room above a cooking appliance therein, which comprises wall means to define a generally rectangular housing having an open bottom, said housing having generally parallel front and rear walls and generally parallel side walls, a front liner provided in said housing and lying in an inclined plane, a rear liner mounted in said housing and extending downwardly at an incline from the upper edge of said front liner, said front and rear liners being transverse to each other, a planar filter means mounted in said rear liner and adapted to filter grease, said rear and front liners, and said filter means, cooperating with the side walls of said housing to define an open-bottomed capture and entrainment chamber adapted to receive fumes from said cooking appliance, blower and exhaust means to draw air through said filter means from said capture and entrainment chamber and to discharge such air to a region exterior to said room, supply conduit and blower means to supply air from a region exterior to said room to the region of said housing between said front liner and said front wall of said housing, vertical throat means to conduct supply air downwardly from said last-mentioned housing region to the vicinity of the lower portion of said housing, said vertical throat means being defined in part by a generally vertical plate which extends downwardly from said front liner, and generally horizontal throat means to receive such supply air and to direct the same into said capture and entrainment chamber in a generally laminar stream or curtain, said horizontal throat means being so directed that said stream or curtain passes directly through said capture and entrainment chamber, in an upward and rearward direction, and strikes said filter means, whereby a portion of said supply air which strikes said filter means rolls upwardly into engagement with said front liner, then flows forwardly down said front liner, then passes downwardly along said vertical plate, and then passes rearwardly across said capture and entrainment chamber back to said filter means, said flow of said portion of supply air constituting a very large-diameter vortex.

Claim 54

A self-contained fume hood adapted to be mounted in a room over a cooking appliance, which comprises: a rigid rectangular housing having a front wall, a rear wall, and parallel side walls, means to define a capture and entrainment chamber in said housing, the portion of said housing beneath said chamber being open whereby to permit convection of fumes upwardly from said cooking appliance into said chamber, a grease filter mounted in said housing remote from said front wall thereof and exposed to said chamber, exhaust conduit and blower means to draw air and fumes through said filter from said chamber and to exhaust said air and fumes to a region exterior to the room in which said housing is mounted, supply conduit and blower means to pump supply air from a region exterior to said room to a portion of said housing exterior to said chamber and adjacent the upper region of said front wall of said housing, means provided in said housing to direct said supply air downwardly from said housing portion and thence rearwardly across said capture and entrainment chamber to said grease filter in a substantially laminar curtain into which fumes from said cooking appliance are entrained, a large part of the air in said curtain, and the fumes entrained therein, passing directly through said filter, and means to cause another large part of the air in said curtain to roll upwardly off said filter, thence forwardly across the upper part of said chamber, thence downwardly to the upper part of said curtain, and thence rearwardly to said filter, said flow effected by said last-named means being a large vortex located above said curtain.

Claim 55

A self-contained fume hood adapted to be mounted in a room over a cooking appliance, which comprises: a rigid rectangular housing having a front wall, a rear wall, and parallel side walls, means to define a capture and entrainment chamber in said housing, the portion of said housing beneath said chamber being open whereby to permit convection of fumes upwardly from said cooking appliance into said chamber, a grease filter mounted in said housing remote from said front wall thereof and exposed to said chamber, exhaust conduit and blower means to draw air and fumes through said filter from said chamber and to exhaust said air and fumes to a region exterior to the room in which said housing is mounted, supply conduit and blower means to pump supply air from a region exterior to said room to a portion of said housing exterior to said chamber and adjacent the upper region of said front wall of said housing, means provided in said housing to direct said supply air downwardly from said housing portion and thence rearwardly across said capture and entrainment chamber to said grease filter in a substantially laminar curtain into which fumes from said cooking appliance are entrained, a large part of the air in said curtain, and the fumes entrained therein, passing directly through said filter, and means to cause another large part of the air in said curtain to roll upwardly off said filter, thence forwardly across the upper part of said chamber, thence downwardly to the upper part of said curtain, and thence rearwardly to said filter, said flow effected by said last-named means being a large vortex located above said curtain.