|Publication number||US3263343 A|
|Publication date||2 Aug 1966|
|Filing date||12 Nov 1963|
|Priority date||12 Nov 1963|
|Publication number||US 3263343 A, US 3263343A, US-A-3263343, US3263343 A, US3263343A|
|Inventors||Loos John H|
|Original Assignee||Gen Motors Corp|
|Export Citation||BiBTeX, EndNote, RefMan|
|Patent Citations (2), Referenced by (27), Classifications (7)|
|External Links: USPTO, USPTO Assignment, Espacenet|
Aug. 2, 1966 J. H. LOOS 3,263,343
LINT DISPOSER FOR CLOTHES DRYER Filed Nov. 12, 1963 5 Sheets-Sheet 1 INVENTOR. John H. Loos His A/forn e y Fig. l
Aug. 2, 1966 J. H- 1.005
LINT DISPOSER FOR CLOTHES DRYER 5 Sheets-Sheet ,2
Filed Nov. 12, 1963 m w m E w J W0 L H 0 o J 9 3 n R 5 n 3 .0 H 4 6 9 O 6 2 4 8 s A i .9 V 6 S u /6 a H 5 w W m M m w w M His A fforney United States Patent 3,263,343 LINT DISPOSER FOR CLQTHES DRYER John H. Loos, Dayton, Ohio, assignor to General Motors Corporation, Detroit, Mich, a corporation of Delaware Filed Nov. 12, 1963, tier. No. 322,844 10 Claims. (Ci. 34-82) This invention relates to a domestic appliance and more particularly to an improved continuous lint burner for a clothes dryer.
One of the most frequently heard objections to the domestic clothes dryer involves the elimination of lint which is generated during the tumbling of clothes. Commonly assigned copending applications Ser. No. 710,808, filed January 23, 1958, now Patent No. 3,132,006, suggests burning the lint continuously in order to reduce the lint to an inconsequential ash residue.
Accordingly it is an object of this invention to provide an improved continuous lint burner for a clothes dryer which is more readily accessible.
Another object of this invention is the provision of a continuous lint burner for a clothes dryer which is mounted on the door of the clothes dryer for improved air flow control.
A further object is the provision of a continuous lint burner which is mounted on a dryer door, thereby making the device an interchangeable option available as an accessory for prior art dryers not so equipped.
A more specific object of this invention is the provision of a door mounted continuous lint burning arrangement including means for eliminating the smoke and odor from burning lint and means for preventing the burning of wool lint.
Further objects and advantages of the present invention will be apparent from the following description, reference being had to the accompanying drawings wherein preferred embodiments of the present invention are clearly shown.
In the drawings:
FIGURE 1 is a perspective view of a clothes dryer having its access door in an open position;
FIGURE 2 is fragmentary rear elevational view, with parts broken away, to show the improved door mounted lint burning arrangement of this invention;
FIGURE 3 is a side sectional view, partly in elevation, of a domestic clothes dryer provided with this invention; 7 FIGURE 4 is an enlarged, fragmentary side sectional view of a preferred embodiment of the lint burning and smoke eliminating clothes dryer door of this invention; and
FIGURE 5 is a side sectional view similar to FIGURE 4 of another embodiment of this invention.
In accordance with this invention and with reference to FIGURE 1, a clothes dryer is shown with a cabinet having a front wall 12 in which a recessed opening 14 is provided. The recessed opening 14 terminates in an inset wall 16 which circumscribes an access opening or drum outlet port 17 in communication with a tumbling drum 19 therebehind. Adapted to close the opening 14 is a vertically pivoted door 20 having a lint eliminating housing 22 mounted thereon and adapted to extend into said opening 17 when the door 20 is in closed position.
The lint eliminating housing 22 is adapted to project into intercepting air flow relationship with air moving outwardly through opening 17 on its way to an arcuate series of ports 24 along the bottom of a front port plate or collar 26. The lint eliminating housing 22 is formed with a vertical inlet or inner panel 28 in which a plurality of inlet ports or perforations 30 are formed. The lint screen guard or inner panel 28 is joined to the inner door panel 29 at the inner end of a drawn circumambient housing wall or duct means portion 34 thereof. Since air must flow through the housing 22 on its way from the drum opening 17 to the port plate openings 24, the circumambient wall 34 is provided further with an exhaust opening 42 in a bottom portion thereof to permit air to leave the housing 22. The peripheral jointure 35 where inner and outer door panels meet should be airtight to prevent ingress of air to the housing 22.
To more clearly understand the structure of a clothes dryer suitable for use with this invention, reference may now be had to FIGURE 3. The clothes dryer 10, in addition to its front wall 12, door 20 and lint eliminating housing 22, includes a top cabinet portion 48, a rear Wall 50, and sidewalls 52, 53. Extending generally parallel to the rear wall 50 is an interior bulkhead 56 for mounting the tumbling drum 19. The tumbling drum is generally cylindrical in form and includes a rear wall 60 which is perforated at 61 to permit ingress of air through the wall. A shaft 62 is aifixed to the wall 60 and is journaled in a spherical bearing 64 carried by the partition or bulkhead 56. Opposite the rear wall 60 in the drum is an annular front wall 66 which terminates in a generally cylindrical neck or collar portion 63 in axial alignment with the opening 17 formed by the inwardly directed collar of the port plate 26. It may be seen in FIGURE 4 that the port plate 26 has a radially outwardly directed flange 70 which is carried in a seal 72 and fixed thereby relative to the recess wall 16 of the cabinet opening. Thus, the front collar 68 of the tumbling drum 19 circumscribes the drum support collar 17 of the port plate 26 and is supported thereby in a manner taught more particularly in the patent to Whyte, 2,843,945, issued July 22, 1958. In this way the tumbling drum 19 is supported for rotation and jour naled at its rear wall on the partition 56 and at its front end by the port plate 26. The port plate 26 may be fas tene-d to the front wall 12 of the dryer by any suitable fastening means such as by screws 77. In order to im prove the agitation of clothes within the tumbling drum during rotation thereof, bafiies such as 78 may be included.
The air flow through the clothes dryer 10 is motivated by a blower 80 (FIGURE 3) which is driven by a motor or other suitable prime mover 82 which serves also to rotate the tumbling drum 19 through a belt and pulley arrangement 84. Although this invention is not so limited, the clothes dryer 10 is of the vented type-the rear wall 50 being provided with inlet openings 86 which communicate with the tumbling drum through an opening 88 in the rear bulkhead 56. Serving as the means for heating incoming air is an electrically energizable heater 90 which is mounted within an annular chamber 92 between the rear bulkhead 56 and perforated rear wall 60 of the tumbling drum. An annular seal 94 defines the peripheral limits of the annular space 92 and may be of any suitable flexible material such as felt mounted in a channel formed by an annular bracket 96 on the rear bulkhead 56.
Adjacent the front wall 12 of the dryer 10 and connected to the port plate openings 24 is a front duct 100. This duct 100 extends downwardly and channels the air to the inlet of the blower 80 thereby completing an air flow path past the heater 90 and through the tumbling drum 19 and the lint eliminating housing to the blower 80. Leading from the blower 80 is an outlet or discharge c-onduit 106 which is connected to the atmosphere in the case of a vented dryer or to the inlet chamber 92 in the case of a recirculating or condensing dryer.
During operation clothing or other material will be tumbling within the drum 19 and the heater currents of air will intermingle with the clothes, picking up the moisture and lint therefrom prior to egress from the tumbling drum through the drum outlet 17. At this point, air is drawn into the lint eliminating housing 22 through perforations 30 in the inner panel 28. An annular seal 110 circumscribes the outer limits of the inner panel 28 in a manner to engage a beveled annular portion 112 of the port plate 26 when the door 20 is closed. The seal 110 engages the port plate between the port plate openings 24 and the air outlet opening 17 from the drum to direct all air flow through the lint eliminating housing 22. As this heated air passes through the housing 22, it will be filtered of foreign matter and will pass then through the exhaust opening 42 in the housing.
Turning now to FIGURES 2 and 4, the preferred embodiment of the door mounted lint burner will be described. Within the lint eliminating housing 22 a radially inwardly turned portion 120 of the cylindrical wall or duct means 34 has an annular shoulder portion 122 for receiving in sealing engagement therewith the outer peripheral edge or annular frame 124 of the disc-like lint collecting screen 126. Thes'creen 126 is tightly stretched on the frame 124 and positioned to intercept air flow proceeding from the openings 30 in the inner panel to the exhaust outlet 42 from the lint eliminating housing. The steel hub, welded or staked to the screen 126, is journaled at one end in a depression or thrust bearing in the lint burner housing as at 128 (springs 129 push housing 134 against the said one end) and at the other end is mounted on a drive shaft or pinion 130 which extends through a support channel 32 from a prime mover means having a gear reduction unit 131 and a drive motor 132. The screen is adapted to be driven by the motor in the speed range between /6 r.p.m. and A r.p.m. All lint passing through the lint eliminating housing will be trapped on the side of the screen 126 facing the tumbling drum; and this trapped lint is slowly rotated into juxtaposition with a lint burning heating element 140 for incinerating the lint.
Within the lint eliminating housing 22 is an open-sided box-like lint burning housing 134 supported on the inner panel 28 and having any type of high temperature insulation 136 backing up a slight recess 138 in which the lint burning heating element 140 is positionedaluminum clad steel forming the recess 138 to reflect the heat toward the screen 126. Note that the heating element 140 is close enough to the upstream side of the screen 126 so that the lint on any portion of the screen in proximity therewith will be surely and quickly incinerated as the screen portion is rotated past the heater. Electrical conduits for energizing the motor 132 and the heater 140 may be channeled to the door through a protective hinge arrangement taught in the patent to Haslup, 3,042,471, issued July 3, 1962.
A quantity of smoke and odor accompanies the lint burn process. For this reason an open-sided box-like smoke and odor eleminating or catalyst housing 142 is supported on the vertical channel 32 and positioned adjacent the lint burning housing 134 on the opposite or downstream side of the screen 126. A catalyst 144 is carried in this housing 142 between support screens 143, 145 and acts to eliminate the products of combustion by altering the smoke and odor to make them colorless and odorless. Platinum coated alumina or chromia alumina in bead or pellet form has been used successfully as the catalyst. A honeycombed ceramic called Cercor marketed by Cornning Glass Co. has been coated with a precious metal (platinum) and also used in place of the bead-like catalyst.
The catalyst housing 142 has in the rear thereof exhaust outlets or louvres 146 through which the altered products of combustion are withdrawn. The normal suction of the clothes dryer blower 80 will cause the smoke generated in the area between the heating element 140 and the catalyst 144 to be drawn through the catalyst for alteration thereof-the colorless, odorless results being withdrawn through the exhaust louvres 146, the exhaust outlet 42 of the lint eliminating housing and the ports 24 in the front port plate into the front duct 100. Note that the housings 134 and 142 snugly sandwich the screen therebetween. This leaves only a small or restricted air flow connection 147 with the duct means 34 around the periphery of the housing 134 at the screen 126. When the blower is operating, a full air flow is drawn through the lint eliminating housing duct means 34 with the lint burning housing 134 serving as an air flow shield for the area where lint is being burned. A lesser or reduced quantity of air is drawn through the burn and smoke elimination area when the door is closed as determined by the combined flow resistances of the duct connection 147, the screens 126, 143 and 145, the catalyst 144, the louvres 146 and the exhaust opening 4.2. The variation of any of these can regulate the reduced air flow. As a matter of fact air flow control in the door mounted continuous lint burner is much improved over the device in the aforementioned copending application.
In the embodiment of FIGURES 2 and 4 with door 20 closed the lint collecting screen 126 is rotated continuously throughout a clothes drying cycle and the lint burning heating element is energized concurrently with the dryer operation. Where the door 20 is opened during the drying cycle while the lint is burning, air flow through the lint eliminating housing 22 will stop. Although the heater will be immediately deenergized, a small residue of smoke may remain. The occurrence of such 'a smoke and odor residue has not been troublesome in the preferred embodiment. However, if every vestige of noxious prod ucts of combustion is to be removed the embodiment shown in FIGURE 5 may be used.
The lint eliminating arrangement shown in FIGURE 5 is identical with that shown in FIGURE 4 with the exception of the means used to draw the smoke through the catalyst bed v144 and the addition of a Wool lint collector 149. In this second embodiment a sepanate impeller 150 is used and adapted to :be driven by a second motor 152. Thus, so long as the motor 152 remains energized, even with the door 20 open, any smoke and odor being generated by the burning of lint will be sucked through the catalyst bed and thereby converted to colorless and odorless products.
The wool lint collector or filter 149 is rather like a hair net designed to slip over the perforated panel 28 of the lint eliminating housing to prevent wool lint (the cause of a rather persistent odor when burned) from reaching the screen 126. The lint collector is installed as shown in FIGURE 5 only whenever excessive amounts of wool are being dried, such as a wool blanket. More particularly, the collector is formed with a circular section 154 of nylon mesh (4245 mesh) and a peripheral elastic band 156 to retain the collector on the housing 22.
It should now be seen that an improved continuous lint burning arrangement has been provided for a clothes dryer-a compact arrangement which is accessibly mounted on the door of the clothes dryer and adapted thereby to be interchangeable with doors on dryers which were not originally supplied with the lint burning feature.
While the embodiments of the present invention as herein disclosed, constitute preferred forms, it is to be understood that other forms might be adopted.
What is claimed is as follows:
1. A fabric dryer comprising a casing defining a drying chamber and having an air inlet opening and an air outlet opening therein, door means vertically hingedly mounted with respect to said casing for closing said air outlet opening, lint eliminating means supported on said door means for burning lint carried from the fabric through said air outlet opening and for causing the products of said burning to be colorless and odorless, and blower means operable for circulating air flow sequentially through said drying chamber and the lint eliminating means when said door means is closed, said lint eliminating means including housing means having a perforated inlet panel portion parallel to said door means extending sealingly into air intercepting relationship with said air outlet opening, and having an exhaust port connected in air flow supply relationship to said blower means, a flat, circular screen member positioned extending across said housing means downstream from said perforated panel portion and parallel therewith and having at least a section thereof in intercepting air fiow relationship to the flow of air from said air outlet opening to said exhaust port to form a lint catering barrier, said screen member being rotatably mounted and positioned so that rotation of said screen member causes said at least a section thereof alternately to be placed in intercepting air flow relationship and then to be removed from said intercepting air flow relationship, motor means on said door means for rotating said screen member, means forming an insulated lint burning chamber within said housing means blocking a portion of said perforated inlet panel in a manner to shield air flow from that section of said screen mmeber which is removed and enclosing heating means positioned adjacent that section of said screen member which is removed for buming lintcaught on said section of said screen member, and means forming a smoke and odor eliminating chamber on the opposite side of said section of said screen member from said heating means and sandwichin-g said screen member section therebetween, said means forming the lint burning chamber being spaced slightly from said means forming the smoke and odor eliminating chamber to permit passage of said screen member and a limited flow of air therebetween, said smoke and odor eliminating chamber enclosing catalyst means in communication with the smoke .and odor resulting from said burning lint and including restricted outlet ports in communication with said blower means through said exhaust port in said housing means for conveying said limited flow of air from said portion of said screen member to said catalyst means thereby to draw the smoke and odor from said burning lint to said catalyst means when said blower means is operating and said door means is closed.
2. The fabric dryer of claim 1 including impeller means connected to said restricted outlet ports in said smoke and odor eliminating chamber and operable to draw smoke and odor from said burning lint to said catalyst means when said impeller means is operating irrespective of whether said door means is open or closed.
3. A fabric dryer comprising a casing defining a drying chamber and having an air inlet opening and an air outlet opening therein, door means movably mounted with respect to said casing for closing said air outlet opening, lint eliminating means on said door means for burning lint carried from the fabric through said air outlet opening and for causing the products of said burning to be colorless and odorless, and means for circulating air sequentially through said drying chamber and the lint eliminating means when said door means is closed, said lint eliminating means including housing means having an inlet portion connected to said air outlet opening, a lint filter member positioned extending across said housing means downstream from said inlet portion and having at least a portion thereof in intercepting air fiow relationship to the flow of air from said air out-let opening to form a lint catching barrier, said lint filter member being movably mounted and positioned so that movement of said lint filter member causes said at least a portion thereof alternately to be placed in intercepting air flow relationship and then to be removed from said intercepting air flow relationship, means for moving said lint filter member, means forming .a lint burning chamber in said housing means in air flow shielding relationship to that portion of said lint filter member which is removed and including means positioned adjacent that portion of said lint filter member which is removed for burning lint caught on said portion of said lint filter member, and means forming a smoke and odor eliminating chamber on the opposite side of said portion of said lint filter member from said burning means and including smoke and odor altering means in communication with the smoke and odor resulting from said burning lint, said smoke and odor eliminating chamber including means in communication with said air flow circulating means for conveying at least a portion of the flow of air from said portion of said lint filter member to said smoke and odor altering means thereby to alter the smoke and odor from said burning lint to colorless and odorless products.
4. The fabric dryer of claim 3 wherein said means for conveying is an air duct having one end in restricted communication with said smoke and odor eliminating chamber and its other end in communication with said air flow circulating means.
5. The fabric dryer of claim 3 wherein said means for conveying is an impeller interposed in limited air flow inducing relationship between said smoke and odor eliminating chamber and said air flow circulating means.
6. A continuous lint burning fabric agitator comprising a drum for agitating said fabric and having an opening, a door for closing said opening, a lint eliminating means on said door, a blower for producing a first air flow through said drum and said lint eliminating means, duct means including said lint eliminating means connecting said drum and said blower, a rotatably mounted lint collecting surface in said lint eliminating means between said blower and said drum, means forming a compartment adjacent at least a portion of said surface to shield said portion from said first air flow and having restricted connections with said duct means, a lint burn heater in said compartment adjacent said surface, a smoke and odor altering means in said compartment adjacent said heater and downstream from said portion of said lint collecting surface, said restricted connections of said compartment with said duct means conveying a second air fiow through said compartment; and power means for moving said drum, blower and lint collecting surface.
7. A continuous lint burning fabric agitator comprising a drum for agitating said fabric and having an opening, a door for closing said opening, a lint eliminating means on said door, a blower for producing a first air flow through said drum and said lint eliminating means, duct means including said lint eliminating means, a rotatably mounted lint collecting surface in said lint eliminating means in air flow intercepting relationship to said duct means, means forming a compartment adjacent at least a portion of said surface to shield said portion from said first air flow and having a restricted connection with said duct means, a lint burn heater in said compartment adjacent said surface, and means connected to said compartment downstream from said portion of said lint collecting surface for removing smoke and odor resulting from burning lint, said restricted connection of said compartment with said duct means conveying a second air flow through said compartment to said removing means.
8. A door construction adapted for burning lint when used with a clothes dryer, said door construction comprising an outer imperforate panel and an inner perforate panel adapted for receiving a stream of air from the clothes dryer, duct means spacing said inner and outer panels to form a lint eliminating chamber therebetween and having an exhaust opening, a circular screen rotatably journaled on said outer panel and having a portion thereof extending across said duct means between said inner panel and said exhaust opening and rotatably in a manner to alternately intercept and be removed from air flow between said inner panel and said exhaust opening, an insulated lint burning housing between said inner panel and the portion of said screen which has been removed, said housing including a recess open toward said screen on one side thereof enclosing a heater adjacent the portion of said screen which has been removed, a smoke altering casing adjacent said recess and open toward said screen on the opposite side thereof enclosing a catalyst means for eliminating smoke and odor, means including an impeller for impelling air from said duct means into the space between said heater and said catalyst means and from said space through said catalyst means to said exhaust opening, and power means supported in fixed relationship to said outer panel for rotating said screen at one speed and said impeller at another speed.
9. A door construction adapted for burning lint used with a clothes dryer, said door construction comprising an outer imperforate panel and an inner perforate panel adapted for receiving a stream of air from the clothes dryer, duct means spacing said inner and outer panels to form a lint eliminating chamber therebetween and having an exhaust opening, a circular screen rotatably journaled on said outer panel and having a portion thereof extending across said duct means between said inner panel and said exhaust opening and rotatable in a manner to alternately intercept and be removed from air flow between said inner panel and said exhaust opening, an insulated lint burning housing between said inner panel and the portion of said screen which has been removed, said housing including a recess open toward said screen on one side thereof enclosing a heater adjacent the portion of said screen which has been removed, a smoke altering casing adjacent said recess and open toward said screen on the opposite side thereof enclosing a catalyst means for eliminating smoke and odor, means for conveying air from said duct means into the space between said heater and said catalyst means and from said space through said catalyst means to said exhaust opening, and power means supported in fixed relationship to said outer panel for rotating said screen.
10. The door construction of claim 9 including a removable mesh-like hood covering said inner panel for removing wool lint when the door is adapted for use with a clothes dryer drying fabric having wool therein.
References Cited by the Examiner UNITED STATES PATENTS 12/1962 Mitter et al 34-82 X 5/1964 Brucken 34-79
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|U.S. Classification||34/82, 55/400, 34/595|
|International Classification||D06F58/20, D06F58/22|