US 3155462 A
Description (OCR text may contain errors)
Nbv. 3, 1964 c. E. ERICKSON ETAL 3,155,462
CLOTHES DRYING CABINET WITH A BIASED ROTARY DRUM Filed Oct. 51. 1961 3 Sheets-Sheet 1 ENTOR.
INV CLIFFORD E. ERICKSON S EORGE M. STONE ATTORNEY A 1964 c. E. ERICKSON ETAL 3,155,462
CLOTHES DRYING CABINET WITH A BIASED ROTARY DRUM Filed Oct. 31. 1961 a Sheets-Sheet 2 FIG. 7
INVEN TOR. CLIFFORD E. ERICKSON BgEORGE M. STONE W Quad 9' ATTORNEY 6 c. E. ERIICKSON ETAL 3,
CLOTHES DRYING CABINET WITH A BIASED ROTARY DRUM Filed Oct. 31 1961 3 Sheets-Sheet 3 FIG. 9
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ATTQRNEY ll5 V. 60 C. A.C.
United States Patent 3,155,462 CLOTI-ES DRYING CABINET WITH A BIASED RGTARY DRUM Clifford E. Erickson, Chicago, and George M. Stone,
This invention relates to clothes drying apparatus, and in particular, to a clothes dryer providing for the tumbling of clothes in a drying chamber of which only one wall or a major portion of one wall is rotatable.
The domestic clothes dryer art appears presently to be founded on two broad types of appliance: the simple cabinet type in which articles which should not be tumbled, such as sweaters, hosiery and the like, are hung in an atmosphere of moving warm air, and the rotating drum type in which the articles of laundry are tumbled in a similar atmosphere. These two types of dryers are not actually interchangeable'for use in a particular sense, for even in tumbler dryers in which the drum rotating mechanism may be disconnected without interfering with the blowing and air heating means, the space limitation of the drum and the conventional front loading requirement preclude the hanging of clothing so as to derive maximum benefit from the dryer operation. It is, of course, obvious that it would be impractical to attempt to dry sheets or other large articles in a stationary cabinet dryer, for it would be necessary to fold the damp sheets to a size consistent with the cabinet size and to hang or drape the sheets over rods or the like within the cabinet.
It is known also that in rotating drum dryers of the sotermed automatic type in which, by means of timing switches and condition-sensing devices, the operation of the dryer is terminated upon attainment of preselected time or factors such as temperature or dampness of the clothes, it is diflicult accurately to sense either the temperature or the dampness of the articles of clothing, for if the condition-sensing devices are not in the wall of the drum so as actually to be contacted by the articles of clothing as they tumble within the drum, the temperature or humidity condition which is sensed is only an approximation, at best. To mount such devices in the wall of a conventional rotating drum requires slip rings or the like to establish the electrical connections. These arrangements are quite unsatisfactory, for the humid atmosphere in which they must operate accelerates the deterioration of the contacting surfaces.
It is therefore an object of our invention to provide a clothes dryer which may be eificiently and easily employed to tumble-dry and to still-dry articles during a single operation of the dryer.
It is another object of the invention to provide a clothes dryer of the tumble-action type in which the major portion of the drying chamber is stationary, thus lending itself to the efficient and economical mounting of thermostats or hygrostats in optimum locations for sensing the physical condition of the articles being dried.
It is still another object of the invention to provide a clothes dryer of the tumble-action type in which the drying chamber permits of loading from the top, from the front, or from either side. 7
It is a further object of the invention to provide a clothes dryer of the tumble-action type in which the facilities for loading the dryer are such that the dryer may optionally be installed as a free-standing appliance It is yet another object of the invention to provide a clothes dryer of the tumble-action type in which the tumbling mechanism is light in weight and may be rotatably supported on a single structural element which forms a part of the blower casing and the air-heating chamber.
In a presently available form of our invention, we utilize a rectangular exterior cabinet in which the front to-rear dimension is 24 inches, and therefore, of a depth compatible with the depth of the average undercounter cabinet. The width of the cabinet is only about 18 inches, and the height is compatible with the normal clearance below a 36-inch high countertop. An upper portion of the front cabinet panel'and a portion of the top wall of the cabinet may comprise a hinged loading door, whereupon the dryer may be loaded from the front, top, or either side with equal facility. Within the cabinet, arranged obliquely to all of the walls thereof and extending from the bottom to the top, we provide a main structural member comprising a rigid plate which supports a drivemotor, a fan and fan housing, a plenum chamber, and bearing structure for the tumbling mechanism. We find it advantageous to incline said plate rearwardly; an inclination of between 10 and 20 degrees from the vertical gives excellent operational results. The oblique position and rearward inclination of the support plate makes it possible. to rotatably mount thereon a conical or frustoconical structure which will be in a posture looking upwardly toward a front corner of the cabinet. This frustoconical structure comprises a wall of a drying chamber in which all of the other walls are stationary. The oblique positioning makes it possible for the diameter of the frusto-conical structure to be substantially more than the actual width of the cabinet. Essentially, the
stationary portion of the drying chambercomprises a light sheet metal structure having an angularly-related rear wall formed with a large opening defined by a flange which enters the frusto-conical structure in telescoping relation therewith. Exterior decorative walls are placed about the drying chamber structure. Means are provided 'to rotate the frusto-conical wall structure and to introduce heated air through the rear hub portion thereof; if desired, certain areas of the door or cabinet wall structure may be foraminated and provided with an appropriate lint-catching mechanism. In any event, the air flow is axially directed relative to the frusto-conical wall as it enters the drying chamber, but strikes front and side wall 'areas at an angle and is deflected thereby, thus producing a live air conditionthroughout the drying chamber. In order to tumble the laundry articles within this moving body of air we provide in the conical structure a plurality of paddles arranged to lift and release the articles for free fall through the air stream. It is a feature of the invention that the paddles do not trap the articles in rubbing contact along the stationary wall structures.
From the above brief description it will be appreciated that the major portion of the drying chamber wall area is stationary and that said stationary wall areas include a and temperature of the laundry articles and to the actual temperature and humidity conditions of the drying chamber atmosphere.
The preferred door arrangement of the cabinet, and also the facilities for optional air discharge locations, make it. possible to employ a supplemental drying chamher or drying chamber extension within which may be hung sweaters or other articles which should not be tumbled during drying. Actually, as will later be apparent, this non-tumbling drying can proceed contemporaneously with a normal tumble-dry operation, thus providing a laundry-drying apparatus whichcan at one and the same time perform two types of drying operation.
Other features and advantages will be apparent from the following detailed description of a presently preferred form, read inconnection with the accompanying drawings in which:
FIG. 1 is a front perspective viewof a clothes dryer embodying our invention with the cabinet door in partly open position;
FIG. 2 is a view of the tumbling mechanism and support structure without the enclosing drying chamber or cabinet;
FIG. 3 is a top perspective view of the basic casing structure without the upper and other external walls of the cabinet, to better show the arrangement of the sta tionary drying chamber;
FIG. 4 is a side sectional elevation taken in section immediately behind the right side of the cabinet as viewed in FIG. 1;
FIG. 5 is a rear elevational view with most of the rear cabinet wall broken away;
FIG. 6 is a fragmentary elevation showing the tumbling cone support structure in section in a vertical plane taken through the axis of rotation;
FIG. 7 is a partial side elevation of a dryer showing the application of a supplemental stationary drying chamber;
7 FIG. 8 is a perspective view of such a supplemental chamber;
FIG. 9 is a front elevation showing a second form of stationary drying chamber adapted to be supported on the top of the dryer cabinet rearwardly of the door thereof;
FIG. 10 is a side sectional elevation taken on lines 1010 of FIG. 9; and
FIG. 11 is. a schematic control diagram.
Referring now to FIGS. 1 and 3, our dryer comprises an inner cabinet structure 1 of sheet metal to the exterior walls of which are attached outer decoration panels forming side walls 2 and 3, a relatively shorttop wall 4, and a lower front wall 5. .The rear of the structure 1 is open, and will be fitted with a rear closure panel, shown fragmentarily in FIG. 5 at the lower left hand corner thereof. It will be noted from FIG. 3 'that the interior .of this cabinet structure 1 has a wall 6 which forms substantially all of the drying chamber. The top wall 7 of the structure 1 is only a partial wall, characterized by the long angular portion 7.1 which establishes the general directional relationship of the rear of the drying chamber. The rear of the interior wall 6 has a large circular opening 8 defined by a rearwardly extending flange 8.1. As
will later be apparent, the opening 8 is not in a vertical plane but rather in a plane which inclines downwardly and forwardly from the portion 7.1, at an angle of about 18. The wall 6 intersects with the front of the structure at the corner 9 and slopes downwardly from there to merge into the lower portion of the opening 8. In brief, the wall 6 is of rather complex curved shape to provide a stationary drying chamber enveloping the opening 8 and having a bottom wall sloping sharply to the bottom of the inclined opening 8.
This structure 1 may be of relatively light weight, for it rests upon the rectangular structural base 10, the front wall 11 of which is foraminated to provide an air intake as later described. This base structure has a fixed bottom wall or bottom brace 12 which provides the supporting base for the member 14 which is the main structural support for all of the moving parts of the dryer. As best shown in FIGS. 2 and 4, the member 14 is angularly positioned within the base and it inclines rearwardly at the 18 angle of inclination of the plane of the opening 8. The member 14 is appropriately flanged and embossed for rigidity as indicated in FIG. 2.
Referring now to FIGS. 4 and 5, it will be noted that the relatively wide front face of the member 14 between its side flanges accommodates the mounting of the main drive motor 15 thereon and for mounting the respective driving and idler sheaves of the tumbling apparatus later described. The rear face provides a wall of the housing 16 of the blower 17. Said blower is directly aflixed to an extension (not shown) of the motor shaft and as is conventional, draws air into the blower casing through the central inlet 18 and discharges it at the tangential outlet 20, which communicates directly into the plenum chamber 21, of which member 14 also forms a wall. The plenum chamber accommodates an air heating mechanism which may be the appropriately supported and insulated electrical resistance coils 22, or any suitable gas-fired heat exchanger (not shown). In the clothes dryer art each of these air heating systems is so well established as to make further description unnecessary. The rear wall 23 of chamber 21 cooperates with the plate 14 to accommodate the shaft 24 of the clothes tumbler 25, FIG. 6, said shaft being freely rotatable in the respective bearings 26 and 27. The tumbler 25 is frusto-conical, having a truncated rear wall 28 to the center of which the shaft 24 is aifixed by any suitable means. Said wall 28 is foraminated and the plate 14 has slots 30 appropriately arranged radially about the shaft 24. Air flows from the plenum chamber through the slots 30 and the openings in the wall 28. To minimize escape of air into the cabinet we provide an annular seal 31 which may be of a lubricant impregnated fibrous material such as felt.
The tumbler 25 has paddles 32 extending from its inner wall. These paddles are preferably of eccentric arch shape, being of maximum depth near the rim of the drum. One or both of the paddles may be radial to the axis of rotation; we have found it advantageous, however, to have one of them radial and the other nonradial. The non-radial paddle slopes away from and in addition, leans away from, the direction of rotation of the tumbler, as suggested bythe upper paddle 32 in FIG. 2. The paddles do not project materially beyond the plane of the opening 8, and therefore will not drag the clothes against the wall 6. The non-radial positioning 'of one of the paddles causes it to deflect the articles placed about exterior surface of the flange 8.1 in sealing relation with the rim 25.1.
The tumbler is arranged to be belt-driven by the sheave and idler system best shown in FIG. 2. The sheave 35 of the motor shaft is belt connected to a larger diameter sheave 36 idly rotatable on a shaft appropriately mounted on the plate 14. Rearwardly of sheave 36 and advantageously integral therewith is a small sheave 37 which drives the belt 38 which encircles the rim 25.1 of thetumbler 25. To maintain the belt under appropriate tension and to insure its proper tracking on the rim 25.1, we may use any suitable arrangement of idler wheels 40, 41, 42. By way of the speed reduction effectedby the various sheaves and the large diameter of the tumbler at its rim-which is of the order of 19 inchesa conventional 1725 r.p.m. appliance motor rotates the tumbler at 40 rpm.
It will be obvious that air issues in a substantially axial direction through the apertures at the base of the tumbler cone, but because the axis of the cone is actually oblique to all of the walls of the drying chamber which are in a facing relation to the cone, there is actually much deflection of the air as it impinges on the chamber walls. The resulting confused air pattern is very advantageous because it insures that all of the articles of clothing are exposed to a live air condition. Heavier laundry articles such as towels and the like which have a greater moisture content, tumble within the more concentrated lair streams issuing through the apertures in .the wall 28, whereas the lighter articles, which may be of synthetic materials less absorbent in water, tend to float toward the front portion of the casing.
The fact that the drying chamber is essentially stationary except for the rotating tumbler cone which comprises a substantial portion of the rear wall thereof makes it possible to adapt the dryer to a wider range of installation practices and use factors than in the conventional rotating drum dryer. The loading door 43, for example, has a vertical portion 44 comprising a part of the front wall of the cabinet and a horizontal portion 45 which forms a part of the top wall of the cabinet. Such a door can be hinged at the bottom of the portion 44, or at the rear of the portion 45, or along either side edge of the portion 44. In any event, opening the door affords access to the dryer chamber from the front or from the top as well as from a side, for it is obvious that one standing adjacent a side of the cabinet can readily reach into the dryer chamber through the space made available at the top and front as the door is opened. Also, the drying chamber provides for optional locations for the discharge of air from the chamber. As suggested in FIG. 4, the vertical portion 44 of the door may be forarninated and house a removable lint catching screen 46 which may be slidably mounted between the inner and outer door panels and removable through an aperture such as the slot 47, FIG. 1. It will be understood that such a screen will have a flange 48 which is normally in an overlying relation with the slot 47, and aflords a means for removing the screen. Alternatively, of course, the screen could be placed in the portion 45. In situations where it is desirable to duct the exhaust to the exterior of the building it is feasible to have a screened opening 49 in the upper front portion of the chamber wall 6, as shown in FIG. 3. Said opening may communicate with a duct (not shown) within the dryer behind the wall 6. Such a duct in turn would discharge through the rear cabinet wall or through a knock-out provided opening (not shown) in the rear of the side walls. An-
tion is adaptable to drying articles which should not be tumbled, and that both types of drying may be carried on concurrently. A simple expedient is the provision of brackets such as 52, FIG. 1, depending from the door portion 45 at each side thereof and serving to mount transversely extending rods over which small articles such as socksmay be draped. a
More elaborate arrangements are shown in FIGS. 7 and 8 and in FIGS. 9 and 10. In FIGS. 7 and 8 an auxiliary drying cabinet 53 is useful with a dryer cabinet having a bottom hinged door. The auxiliary cabinet comprises a box structure having a width adapting it to seat snugly within the main cabinet door space and provided with a gasket 54 preferably of the magnetic type popular in refrigerators to seal against the adjacent metallic cabinet structure. A lower curved wall 55 may be screened to prevent passage of lint into the cabinet 53 if said cabinet is being used to dry articles while the main dryer is tumble drying clothing. The top wall 56 may also have a lint screen. These screens are readily cleanable and need not be removable. A front door 57 hinged in any conventional manner aflords access to the hanger rod 58. I
The second form of auxiliary drying chamber 60 of FIGS. 9 and 10 is arranged to seat on the top panel 4 of the main dryer cabinet. The chamber 60 has any suitably hinged door 61 affording access to the hanger rod 62. The top is provided with a lint screen 63. Lifting handles 64 facilitate handling the drying chamber 60. The bottom wall is formed with an opening 65 im mediately beneath a bafiie or deflector 66. The opening 65 is screened as at 67, FIG. 10, and when the chamber is in position on the cabinet, the opening 65 will register with the opening 59 in the top panel 4 of the principal cabinet, it being understood that when chamber 60 is used, the cap 51 will be removed. The baffle 66 serves to distribute the air entering from the main dryer.
FIG. 11 is a schematic of a simplified dryer control circuit of the time-temperature type. The heating elements 22 are illustrated as being connected across the conventional volt A.C. house lighting circuit, although it is more usual for heaters to be energized at 230 volts A.C. The motor 15 has a start winding 15.1 and a run winding 15.2 together with a centrifugal switch 15.3, which is normally closed to connect both windings in parallel but opens as soon as the motor reaches'running speed to interrupt the start winding circuit and close against contact 15.4 for continued motor operation on the run Winding. A second centrifugal switch 15.5 closes the circuit to the heater 22 when the motor is in its running condition, thus insuring that the heater is not energized until the blower 17 is fully operative.
A conventional timing mechanism 76 has a motor 70.1 of the conventional synchronous Telechron type driving a cam shaft and cams (not shown) which control switch blades 70.2 and 70.3. These blades make or break with their respective associated stationary contacts 70.4 and 70.5 according to the contours of the associated cams (not shown) as well known in the art. It is conventional to have the time switch operate as a master switch by providing means whereby displacing the cam shaft axially in one direction closes the switch, and displacement. in the opposite direction opens the switch. See, for example, Patent 2,619,557, granted November 25, 1952, to D. F. lllian for Program Control Switch, and assigned to our present assignee. In theschematic diagram of FIG. ll the switch 76.5 represents this master switch. The con trol circuit may also include a door switch 71 as well known in the art, which is arranged to be closed when the door 43 is closed. Further, the circuit includes a safety cut out thermostat 72 which may be a bimetal switch placed to sense the air temperature immediately in advance of passage through the openings in the tumbler cone 25 as indicated in FIG. 5. Thermostat 72 is normally closed. It would open in the abnormal situation of failure of the blower to circulate air over the heating units in adequate volume, for example, and upon opening would interrupt operation of all of the dryer components. Finally, the illustrated circuit includes a cycling thermostat 73 which is placed to sense theair temperature condition within the dryer chamber. This thermostat may, for example, be placed in the wall 6 at any suitable location as suggested in FIG. 3.
Briefly reviewing the operation of the dryer under control of .the circuit of FIG. 11:
The user adjusts the dryer control knob (not shown) to establish the desired overall time during which the dryer is to operate. This adjustment moves switches 70.2 and 70.3 to close with their associated contacts 70.4 and 79.5 respectively, and in so doing effects a manual rotation of the cams (not shown) so that the cams will return the respective switches to open position at the end of the selected operational period. Thermostats 72 and 73 will be in their normally closed condition; motor switch 15.3 will be closed to connect windings 15.1 and 15.2 in parallel; switch 15.5 will be open. Assuming that the 7 dryer is loaded and the door 43 closed, switch 71 is then closed. I
Manual operation of the timer cam shaft to close switch 70.5 will begin operation of the dryer. The timer motor 71 will have been energized when the door switch is closed through conductor L2, closed switch 71, 72, switch 70.2, 70.4, the timer motor, and conductor 74 to L1. The main motor is energized through L2, closed switch 70.2 and 70.4, conductor 75, the two motor field coils 15.1 and 15.2, conductor 76, closed switch 70.5, and conductor 74 to L1. After the motor comes to running speed and switch 15.3 closes with contact 15.4 the motor will continue to run on its run winding 15.2 and conductor 77 to L1. Also, when the motor attains running speed switch 1.5.5 will close to energize heating unit 22 through the circuit comprising L1, conductor 77, closed thermostat 73, conductor 78, closed switch 70.3, 0.5, and closed switches 72 and 71 to L2.
It is well known that in a dryer operation the air temperature within the drying chamber rises to an intermediate level which is relatively stationary so long as moisture is being evaporated from the clothes. When the clothes are dry, however, the heat is no longer being used to evaporate moisture, the air temperature will rise quite sharply. The thermostat 73 senses thi temperature increase and opens the heater circuit which interrupts the operation of the heating coils without stopping the other components. The thermostat 73 will re-close as the inflow of relatively cooler air reduces the temperature to the degree commensurate with the operational amplitude of thermostat'73. In the meantime, of course, the timer is continuing to rotate the cams which control the switches 70.2 and 70.3, and depending on the weight of clothes in the dryer and the nature of the clothes, there may be one or more cyclings of the thermostat 73 before the end of the time period opens the switches 70.2 and 70.3 and signifies the end of the dryer operation.
While there has been described What is at present thought to be the preferred embodiment of the invention, it will be understood that various modifications may be made therein and it is intended to cover in the appended claims all such modifications as fall within the true spirit and scope of the invention.
1. A laundry drier comprising, in combination, a cabinet, stationary wall means in said cabinet to provide front, side and top walls and a portion of the rear wall of a chamber within which laundry articles are received to be dried, a loading door in said cabinet affording access to said chamber, a concave rotatable wall structure within said cabinet in interfitting engagement with said stationary rear wall to complete said article-receiving chamber, the concavity of said wall structure facing said loading door, shaft means for said rotatable wall, said shaft means being oblique to all walls of said cabinet, and means on said concave wall structure to effect a tumbling of said articles within said chamber during rotation of said wall structure, means for passing heated air through said chamber, and means for discharging said heated air from said chamber.
2. A laundry drier according to claim 1, in which said article-tumbling means comprise paddle structures fixed to said concave wall structure and disposed substantially wholly within the concavity thereof.
3. A laundry drier comprising, in combination, a cabinet, structure within said cabinet providing a receptacle within which clothes are to be dried, said receptacle being defined in part by wall structures in rectangular relationship and being stationary except for wall means forming at least a major part of an end wall thereof, the base of said receptacle forming a fixed trough-like struc ture sloping toward said end wall means, said base being adapted to gather the clothes and direct them against said end wall means, means for rotating said end wall means about an axis directed toward a front upper corner of said cabinet, paddle structures on said end wall means extending toward said receptacle to engage clothes to tumble the same within said receptacle during rotation of said end wall means,'and means for eifecting movement of air axially through said rotating wall, whereby upon impinging against said cabinet walls said air is deflected for striking the clothes at varying angles during the tumbling thereof.
4. A laundry drier comprising, in combination, a cabinet, structure within said cabinet providing a receptacle within which clothes are to be dried, said receptacle being stationary except for wall means forming at least a major part of an end wall thereof, the base of said receptacle forming a fixed trough-like structure sloping toward said end wall means, means for rotating said end wall means, structures on said end wall means extending toward said receptacle to engage clothes therein to tumble the same within said receptacle during rotation of said end wall means, means for effecting movement of air throughout said receptacle during rotation of said end wall means, and means for hanging articles within said receptacle remote from said rotating wall but within the path of air movement within said receptacle.
5. A laundry drier comprising, in combination, a rectangular cabinet, structure within said cabinet providing a receptacle within which clothes are to be dried, a loading door for said cabinet, said receptacle being stationary except for upwardly and rearwardly extending wall means forming at least a major part of an end wall thereof remote from said loading door, the base of said receptacle forming a trough-like structure sloping toward said end wall means, means for rotating said end wall means, structures on said end wall means extending toward said receptacle to engage clothes therein to tumble the same within said receptacle during rotation of said end wall means, means for effecting movement of air throughout said receptacle during rotation of said end wall means, means including cabinet structure mounted about the opening of said loading door to receive air flow therethrough, and means within said cabinet for hanging articles to be dried in the air stream without tumbling, whereby both still-drying and tumble-drying may be effected simultaneously.
6. A laundry drier comprising, in combination, structure providing a rectangular cabinet, wall means within said cabinet having a circular opening and fixed to interior front, side and top walls thereof and together there- 'with providing a chamber within which laundry articles are to be dried, a frusto-conical structure disposed in said circular opening and forming a part of an end wall of said chamber, said frusto-conical structure having a foraminated central area, means for mounting said frusto-conical structure for rotation about an axis oblique to said cabinet structure, means effecting an air-sealing joint between said fixed wall means and said frusto-conical structure, means for rotating said frusto-conical structure, paddle means on said structure to engage laundry articles to tumble them within said chamber during rotation of said structure, a blower for introducing air into said chamber through said foraminated central area of said frusto-conical structure, means for operating said blower, a loading door on said cabinet remote from said frustoconical structure to afford access to said chamber, and a lint screen in said door providing for the egress of air from said chamber.
References Cited in the file of this patent UNITED STATES PATENTS 2,328,256 Breckenridge Aug. 31, 1943 2,843,945 Vxhyte July 22, 1958 2,875,996 Hullar Mar. 3, 1959 2,878,580 Hughes Mar. 24, 1959 2,959,867 Doty Nov. 15, 1960 2,983,050 Alaback May 9, 1961