US2670549A - Laundry drier - Google Patents

Description

C. S. O'NEILL March 2, 1954 LAUNDRY DRIER 4 Sheets-Sheet 1 Filed Oct. 5, 1951 Charles 6. (fi /fi C. S. O'NEILL March 2, 1954 LAUNDRY DRIER 4 Sheets-Sheet 2 Filed Oct. 5,. 1951 3 IN VENTOR.

Charles 5. O/Yezl,

C. S. O'NEILL LAUNDRY DRIER Filed Oct. 5, 1951 4 Sheets-Sheet 4 ooooo n 000 0 5 000 00 O T M u o 6 M. 0 I 000 0000 V o 000 W I o 000 4 o oo 0. 0

Charles 5 0 Patented Mar. 2, i954 LAUNDRY DRIER Charles S. ONeil, Two Rivers, Wis., assignor to Hamilton Manufacturing Company, Two Rivers, Wis., a corporation of Wisconsin Application October 3, 1951, Serial No. 249,564

6 Claims.

This invention relates generally to dryers and more particularly to a laundry dryer in which the laundry is tumbled.

The general object of the invention is to provide a novel dryer having a drying chamber into which air from the exterior of the chamber is introduced and a portion of the air from the chamber is recirculated and mixed with the air from the exterior.

Another important object is to provide a dryer of the foregoing character, having novel means for effecting the recirculation of air from the drying chamber and for introducing air from the exterior of the chamber, by which the poportion of the two quantities of air is established.

A further object is to provide a dryer of the foregoing character, having a novel blower provided with dual air-impelling means acting separately on the recirculated air and the air introduced from the exterior of the chamber.

Still another object is to provide a dryer in which the air is introduced into the drying chamber in a novel manner.

vOther objects and advantages will become apparent from the following description taken in connection with the accompanying drawings, in which:

Fig. 1 is a front elevational view of a dryer embodying the features of the invention;

Fig. 2 is a rear elevational View with the rear wall ,of the outer cabinet removed;

- Fig. 3 is a vertical sectional view taken on the line 33 of Fig. 2;

Fig. 4 is a vertical sectional view, similar to Fig. 3, but showing a modified form of dryer; and

Fig. 5 is a fragmentary sectional view taken on the line 55 of Fig. 4.

A dryer of the type herein contemplated is.

adapted for home use and has a capacity generally equal to the capacity of the ordinary domestic washing machine so that after one loading of laundry has been washed in the washing machine and the major portion of the water removed, it then may be placed in the dryer for drying.

The dryer herein disclosed comprises generally an outer casing or cabinet, a drum rotatably mounted in the cabinet and constituting a drying chamber, and an air chamber means located preferably at therear of the drum. The air chamber communicates at its perimeter with the interior ofthe drum and is provided with rotary blower means comprising a partition with airiinpelling means. at its opposite faces. One airimpellingmeans is adapted to draw air from the exterior of the drum, while the other air-impelling means is adapted to draw air from some other source such as the interior of the drying chamber. The two quantities of air are mixed in the outer portion of the air chamber and the 'mixture is then forced into the drum for drying the laundry therein. The first mentioned stream of air drawn from the exterior of the drum is arranged to pass over a heating unit so that it will be heated to the desired degree to effect rapid drying when mixed with the other stream of air and discharged into the drying chamber.

When the second air-impelling means draws air from the drum, such air is thus recirculated. The drum is provided with an outlet remote from the point where air is discharged into the drum from the air chamber, and the volume of air passing through the outlet is thus equal only to the air drawn into the air chamber from the exterior by the first-mentioned air-impelling means. The first-mentioned stream of air is preferably drawn from the space between the drum and the outer cabinet so that it will absorb any heat radiating from the drum. Such air is thus preheated prior to passing over the heating element.

In the preferred embodiment shown in Figs. 1 to 3, inclusive, the outer cabinet is indicated generally at H) and preferably is of generally rectangular form comprising a base H, a front wall l2, side walls, and a rear wall l3. The rear wall I 3 is preferably made removable so that driving and supporting mechanism within the cabinet can be accessible for servicing. The cabinet also includes a top wall [4. The base II is preferably provided with a three point support comprising a rigid member 15 adjacent the back wall (see Fig. 3) and a pair of adjustable members It at the front corners. The various walls of the cabinet are, of course, preferably made of sheet metal.

Within the cabinet is a rotatably mounted drum, indicated generally at 20, which is here shown as being cylindrical in shape and formed by a pair of dished members 2| (see Fig. 3) flanged and secured together at their open faces, as at 22. The drum 2!! at its front end is provided with an opening 23 formed by an annular flange 24, there being a corresponding opening in the front wall l2 of the cabinet. The drum at its front end is supported by a pair of rollers 25 engaging the annular flange 24 and supported by an upright 26 mounted on the base ll of the cabinet.

At the rear side of the drum, air chamber means is provided, which in the present instance comprises a cylindrical dished member 30 somewhat smaller in diameter than the drum but rigidly secured to the rear wall of the drum. The rear wall of the drum is provided with a central opening 3! communicating with the interior of the air chamber 38, and is also provided with an annular series of perforations 32 opening from the air chamber adjacent the perimeter of the latter. The air chamber is also provided with a central opening 33, preferably of substantially the same size as the opening 3! and aligned therewith so that air may enter the air chamber through the respective openings 31 and 33,

Within the air chamber is a rotary blower mounted coaxially with the central openings and adapted to positively draw air separately from both the drum and from the exterior of the air chamber through the respective central openings. To this end, the rotary blower comprises a rotatably driven partition or disc member 34 extending radially beyond the margins of the central openings and provided with dual air-impelling means comprising two sets of blades 35 and 36 on its respective faces. The blades 35 and 36 are preferably made in the form of angle members rigidly secured to the disc 34 and placed in a position so as to produce an effective impelling action on the air. In the present instance, the blades 35 are shown as being larger than the blades 36, so that a greater quantity of air will be drawn from the drum than from the exterior of the drum. The size and number of blades on each side may be varied, depending upon the mixture of air desired. Thus, a major portion of the air in the drum may be recirculated. The invention, however, is not limited to this particular arrangement and the sizes of the two sets of blades may differ from that shown.

With the foregoing structure, it will be evident, that upon rotation of the blower, the blades 35 will positively draw air through the opening 3! from the drum 20, while the blades 36 will positively draw air through the opening 33 from the exterior of the drum. Both streams of air are forced outwardly to the outer portion of the air chamber 50 and are there mixed with each other and pass into the drum through the perforations 32. The outer portion of the air chamber thus constitutes a plenum chamber for supplying heated air to the drum. Of course, since air from the exterior of the drum is drawn in through the opening 33, a corresponding quantity of air must be discharged from the drum, and such air passes outwardly through the central opening 23 at the front end of the drum.

The air drawn in through the opening 33 is preferably heated prior to entry into the air chamber. To this end, a heating means is provided', which in the present instance is shown as comprising a series of concentrically arranged electrical heating elements 48 supported by plates M mounted on a sheet metal disc or plate 42 fixedly supported at the rear of the air chamber and spaced therefrom and extending radially beyond the opening 33. The air drawn into the air chamber through the opening 33 thus is forced to pass between the disc 42 and the rear wall of the air chamber 30 and consequently will be heated in passing through this space. The disc 42 is provided with a forwardly extending flange 43 while the rear wall of the drum is provided with a rearwardly extending flange M which together act as a shield to prevent radiation of heat from the heating element outwardly into space between the drum and the outer cabinet.

To supply air to such space, the top wall M, in the present instance, projects forwardly beyond the front wall l2 and thus provides a gap or opening 45 through which air may enter the interior of the cabinet. Such air in passing to the rear of the cabinet flows around the drum 20 and thus absorbs heat radiating from the drum. Such flow of air is thereby preheated before entering the space between the disc 42 and the rear wall of the air chamber 30 for further heating by the heating elements 40.

At the front of the dryer, the front wall I2 is preferably provided with a flange member projecting within the flange 24 on the drum and providing an opening whereby laundry may be readily inserted into the drum. To prevent the air discharged through the front of the drum from entering the space between the drum and the cabinet, a flexible wiper 5|, of annular form, is mounted on the flange 24 of the drum and bears against the adjacent surface of the flange member 50 of the cabinet to provide a seal therebetween.

A door, indicated generally at 52, is mounted Preferably the door carries a screen 54 adapted to extend into the flange member 50 on the front wall so that lint will be removed from the air passing from the drum, and to prevent small articles in the drum from being caught in the exhaust air stream.

The door 52 is constructed to provide an. air duct for the air discharged from the drum.- To this end, the door comprises an outer wall 55 and an inner wall 56. Adjacent the upper part of the door, the inner wall 56 is bulged outwardly as at 5'! to provide a transfer duct 60. The bulged portion 51 overlaps the upper portion of the opening through the flange member 50 so as to communicate with the interior of the drum.

The duct 80 also extends upwardly above the flange member so as to communicate with a passage in the upper part of the cabinet formed by a channel member Bl. extends from the left edge of the duct 50. as

viewed in Fig, 1 when the door is closed, toward the right to a position beyond the periphery of the drum. Communicating with the channel member 6! is a pipe or flue 52 extending rearwardly through the cabinet and opening at itsrear end through the rear wall 13 thereof or through one of the other adjacent walls. Thus, air discharged through the central opening at the front of the drum will pass through such opening into the duct 60 for transfer to the channel member 6! and thence rearwardly through the pipe $2 for discharge at the rear of the cabinet exteriorly thereof.

The screen 54 will remove much of the lint carried out by the air flow from the front of the drum. However, further filtering of the air may be obtained by providing additional filter screens 83 and G4 at the point where the transfer duct 58 communicates with the channel 8|. Preferably the screen 5c is coarser than the screen 63 and the latter is coarser than the screen 64. The central opening 3i in the rear wall of the drum may also be provided with a screen 65 to prevent lint from entering the air chamher.

The drive for the drum and the drive for the rotary blower is combined with means for supporting the rear of the drum. For this purpose, i an upright 10" is mounted on the base if of j The channel member 66 i 5 the cabinet at the rear of the drum and at its upper end it is shown as carrying a sleeve II which extends forwardly from the upright. The rear wall of the air chamber 30 is provided with a spider I2 extending across the central opening 33 therein and at the center, the spider is provided with a hub '73 rotatably mounted on the sleeve 'II. Rotatably mounted within the sleeve H is a shaft I4 extending forwardly beyond the hub I3 of the spider and adapted to receive a hub member I5 to which the disc 34 of the rotary blower is secured. Thus upon rotation of the shaft II, the blower will be rotated while the rear end of the drum is supported on the sleeve II by the spider 12. The disc 42 which supports the heating element 40 is provided with a vertical slot fitting snugly over the upright I and is secured thereto for supporting the heating element. The coils of the heating element 40 terminate at the slot and baffies I6 are mounted on the upright I0 between the ends of the heating element to prevent air from passing upwardly along the upright where there is no heating element.

The drive for the rotary blower and for the drum is combined and comprises a motor 80 mounted on the base II at one side of the casing. The motor carries a pulley 8| which is engaged by a belt I9 extending upwardly over a pulley 82 mounted on the rear end of the shaft I4 and then extending downwardly over an idler pulley 83 and then back to the motor pulley 8!. Thus, the motor drives the shaft I4 to drive the rotary blower. For driving the drum, the idler pulley 35 is mounted on a shaft 86 which also carries a pulley 8i. Entrained around the pulley B1 is a belt 00 which extends about the cylindrical air chamber 30 to drive the drum.

To keep both the belt I9 and the belt 90 taut, the shaft 86 carrying the idler pulley 8E and the pulley 81 is journaled in a bearing member 0| mounted on a plate 02 extending through slots 93 in the upright 10. To the lower right hand corner of the plate 92, as viewed in Fig. 2, a

spring 04 is secured, the spring also being se-' cured to the base II of the cabinet. Thus, the spring 94 tends to pull the plate 92 downwardly and to the right, as viewed in Fig. 2, to keep both belts taut.

The modified form of dryer shown in Figs. 4

and is generally similar to the dryer heretofore described but has a different mode of discharging the air into the drum. Thus, the dryer shown in these two figures comprises a cabinet I0 of substantially the same construction as the form of cabinet shown in the other construction. Within the cabinet is mounted a drum, indicated generally at I00. The drum comprises a cylindrical peripheral wall IIlI secured to two annular end walls I02 and I03. The front wall I02 is provided with a central opening IM through which air from the drum is discharged. The rear wall is also provided with a central opening I05.

Mounted within the drum I00 is a plurality of laundry-tumbling ribs, indicated generally at I05, three such ribs being provided in the present instance. Each rib constitutes a means fordischarging the air into the drum. To this end, each rib comprises an angular member I I0 which extends from one end wall to the other of the drum and is secured to both of these end walls and to the cylindrical wall I00. Both legs of the angular member are perforated, as indicated at III. The rear end wall I03 of the drum is provided-with a plurality of apertures II 2, one

and a rear wall H4. The dished member with the rear wall I03 forms an air chamber communicating at its periphery with the apertures IIZ. Mounted in the air chamber is a rotary blower, indicated generally at II5, which is of the same construction as in the form earlier described. The blower II5 is provided with two sets of air-impelling blades respectively mounted on its opposite faces and adapted to draw air both from the drum through the central opening I05 and through a central opening H6 in the rear wall II A of the air chamber. Outside of the air chamber, a heating means, indicated generally at III, is provided for heating the air drawn inwardly through the opening II6 by the rotary blower. Such air is drawn from the space between the drum I00 and the cabinet I0 and is preheated by heat radiated from the drum.

Thus, the rotary blower I I5 will draw air both from the drum through the opening I05 and from the exterior of the drum through the opening H6 and will force both such streams of air outwardly into the outer part of the air chamber where the two streams of air are mixed. The air then flows through the apertures II2 into the interior of the ribs I06 for passage through the perforations I l I in the ribs to the interior of the drum. In this type of dryer, the damp laundry is carried upwardly at one side of the drum by the ribs I00 and as the laundry approaches the top of the drum the laundry slides off the ribs to being drawn in'through the central opening [I6 in the air chamber, a corresponding amount of air is discharged through the opening H3 in the front end of the drum, as in the case of the first-described form of dryer. The drive means for the.

drum and the rotary blower, as Well as the support for the drum, may be substantially the same as in the other form of dryer.

It will be seen from the foregoing that both forms of dryers herein described provide for recirculation of some of the air from the drum with additional air taken in from the exterior of the drum. Such additional air is heated before entering the drum and thus maintains a sufficient temperature within the drum to effect rapid drying. With a rotary blower of the character herein disclosed, the proportion of air recirculated from the drum and air from outside of the drum is definitely determined by the fact that the blower comprises a central disc or partition member having two sets of air-impelling means at its opposite faces. A definite flow of air recirculated from the drum as well as a definite flow of air from the exterior of the drum is thereby assured.

In the form of dryer shown in Figs. 1 to 3, the mixture of both streams of air is discharged directly into the drum at the periphery thereof. In the form of dryer shown in Figs. 4 and 5, such Such heated air also passes into the drum fiii'xtui'e'of air is discharged from the air chain:- ber into the laundry tumbling ribs and thence through the perforations in the ribs against the laundry being carried thereby, as well as from the ribs directly into the drum, for producing a highly effective drying action.

I claim:

1. A dryer comprising a rotatable drum having an and Wall provided with a central opening and apertures adjacent its periphery, a chamber strut t'ure mounted on said end wall and enclosing said apertures, said chamber structure having an end wall spaced from the end wall of the drum and provided with a central opening, rotary blower means mounted in chamber structure and com= prising a rotatably driven disc having two sets of air impeiling blades respectively mounted on opposite faces thereof for drawing air through the respective openings and discharging it through said apertures into the drum, a plate mounted in spaced relation to the end wall of the chamber structure and extending radially beyond the opening therein, and a heating element mounted in the space between said plate and the end wall of the chamber structure to heat the air drawn inwardly through said space and through the adjacent opening, and a shield secured to the end wall of the chamber structure radially outside the backing plate and extending axially over the space between the end wall of the chamber structure and said plate to prevent outward radiation from the heating element.

2, A dryer comprising a generally rectangular casing having a front wall provided with a dis charge opening, a cylindrical drum rotatably mounted in said casing and having a discharge opening at its front end registering the discharge opening of the casing, said drum at its rear end having a central opening and apertures adjacent its periphery, a cylindrical air chamber structure mounted on the rear end of said drum and enclosing said apertures and having an inlet opening to the interior of said casing aligned with said central opening, and rotary blower means mount ed in said chamber structure and comprising a disc located between said central opening and said inlet opening, and two sets of air impelling blades on the respective faces of said disc for drawing air from the drum and from the interior of said casing and adapted to discharge the air through said apertures into the drum with a portion of the air passing through said discharge opening, said casing having a top wall extending forwardly beyond the front wall and providing a gap therewith for admitting air to the interior of the casing.

3. A dryer comprising a rotatable drum having a plurality of hollow perforated ribs for tumbling laundry within the drum during drying, said drum having a central opening at one end, means mounted on said end of the drum providing an air chamber communicating at its periphery only with the interior of said ribs, said means having a central opening to the exterior of the drum, and rotary blower means mounted in said air chamber and comprising a disc having air im-= pelling means mounted on the opposite faces thereof for drawing air from the drum and from the exterior of the drum respectively and for discharging the air into said ribs for passage through the herifoiatiohs therein into the drum.

L. A dryer comprising a cylindrical drum hav ing end walls, a plurality of laundry tumb'i'ng ribs within said drum, each comprising a perforated angular member extending from one end wall to the other and secured to the cylindrical wall of the drum, said drum having a central opening in one end wall with the latter provided with an aperture within the area of each rib, said end wall being otherwise closed, a cylindfical member mounted on said one end wall and having an end Wall spaced from said one end wall and providing an air chamber confinunlca'tin'g adjacent its e ripiiery with the interior of said ribs through the apertures in said one end wall of the drum, the end wall or the air chamber also having a central opening, and rotary blower means comprising a disc mounted in said air chamber and having air impeiling means mounted on its respective faces for drawing air through the respective central openings and for discharging the air into said ribs through said apertures for passage into the drum through the perforations in said ribs.

5; A dryer comprising a rotatable drum having a plurality of hollow perforated ribs for tumbling the laundry during drying, said drum having an end wall provided with apertures opening into the interior of said ribs,- means mounted on said end wall of the drum providing an air chamber communicating with said apertures, and rotary blower means mounted in said air chamber for discharg ing air from said air chamber only through said aperti'lres to the interior of said ribs and from the ribs through the perforations therein to the imterior of the drum.

6. A dryer comprising a rotatable drum having an end wall provided with a central opening and apertures adjacent its periphery; a chamber structure mounted on said end Wall and enclosing said apertures, said chamber structure having an end wall spaced from the end wall of the drum and provided with a central opening, rotary blower means mounted in chamber structure and comprising a rotatably driven dischaving two sets of air impelling blades respectively mounted on opposite faces thereof for drawing air through the respective openings and discharging it through said apertures into the drum, a circular platemounted in axially spaced relation to the end wall of the chamber structure and extending radially beyond the central opening therein to provide an annular opening to the space between the end wall of the chamber structure and said.

plate at the periphery of the plate to permit air to be drawn radially inward through saidspac e, and an annular heating element mounted in said space to heat the air passing through said space.

CHARLES S. ONEIL.

References Cited in the file of this patent UNITED STATES PATENTS Number Name Date v 1,35c, 599 White Nov. 9, 19,20 1,655,5l4 seiuert Jan. 10, 1928 2,039,429 Lydon May 5,- 193 2,280,794: nurxthal A r.- 21, 1942 1 Mar. 2,498,172

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