US 2334025 A
Descripción (El texto procesado por OCR puede contener errores)
Nov. 9, 1943.
L. M., Q'NEILL DRIER Filed March 29, 1940 Zhnen-Sheet 1 v lime/fof Zeb /l/f. 'OWeL'ZZ Nov. 9, 1943. L. M. oNElLL.
DRIER jveiz for OWezlZZf Leo Patented Nov. 9, 1943 UNITED STATES PATENT OFFICE DBIEB Leo lVL O'Neill, Evanston, lll.
Application March 29, 1940, Serial No. 326,889
The invention relates generally to driers and more particularly to a device for drying wet fabrics such as laundry.
The general object of the invention is to provide a novel drier utilizing a maximum of the heat generated by a source of heat, for the purpose of evaporating the moisture within the articles being dried.
It is also a general object to provide a novel drier for drying fabrics such as laundry in a relatively short space of time and which sterilizes the fabrics and leaves them in a fluffy unmatted condition.
Another object is to provide a drier which is of relatively simple and inexpensive construction, which does not involve any dangerous temperatures, and which is easy to operate.
Still another object is to provide a drier in which the rate of drying does not depend upon the humidity conditions of the air in the room in which it operates, and to only a negligible extent does the rate of drying depend upon the temperature of the room.
Further objects reside in the provision of a drier having means for collecting and disposing of water vapor discharged from the drier proper, of a drier which avoids discharging a large volume of heated air into the room in which it operates, and of a drier in which any lint from the articles being dried is collected so as not to be discharged into the room.
Other objects and advantages will become apparent from the following description taken in connection with the accompanying drawings, in which:
Figure l is a perspective view of a drier embodying the features of the invention.
Fig. 2 is an enlarged vertical sectional view of the drier shown in Fig. 1.
Fig. 3 is a vertical sectional view taken on the line 3-3 of Fig. 2.
Fig. 4y is a fragmentary sectional view takenon the line 4 4 of Fig. 2.
Fig. 5 is a fragmentary rear view of the drier.
Fig. 6 is a fragmentary plan view partially broken away to show the condenser construction.
Many types of driers for fabric materials have heretofore been constructed, but in practically all of such driers, the principal mode of drying the fabrics has been by placing the fabrics in a current of heated air. The heat of the air causes the moisture in the fabrics to vaporize and be carried oil' along with the air. There are two principal disadvantages to a drier .of this type. One is that a large amount of the heat is wasted because of the large volume of air which has to be heated in order to effect drying. The air when taken into the drier of course has to be heated from the intake temperature sumciently to cause vaporization of the moisture content of the fabrics. However, the heat that may be utilized for such vaporization is only a fractional part of the total heat imparted to the air, since necessarily the air leaves the drier at a much higher temperature than the incoming air. If the drier is operating in a closed room, the temperature of the room will be raised considerably because of the large volume of heated air discharged into lt by the drier, and such air is obviously excessively humid.
The other principal disadvantage is that the air as taken into the drier may contain a large percentage of humidity. The moisture thus carried by the air has to be heated along with the air and decreases the amount of heat available for vaporizing the moisture content of the fabrics. Obviously this increases the amount of heat that has to be supplied by the drier, and subjects the rate of drying attainable by the drier to the humidity conditions of the air of the room in which it operates. When the drier operates in a closed room, as mentioned above, the rate of drying obviously will decrease as the drying cycle progresses because of the increasing percentage of humidity in the air of the room.
A drier embodying the features of the invention avoids these disadvantages by utilizing a maximum part of the heat generated within the drier solely for the purpose of evaporating the moisture content of the fabrics. is by radiation from the drier as a whole, which loss is reduced to a minimum by the heat insulated construction of the drier. To this end, air ls prevented from entering the drier during the drying cycle so that none of the heat is wasted in heating air which would thereby carry the'heat out of the drier.
The drier comprises generally a closed chamber within which is placed a source for generating heat as distinguished from a means for supplying the chamber with a heated medium such as air. The articles to be dried are placed within the chamber, and the moisture content thereof is thereby subjected to the heat generated within the chamber to cause vaporization of such moisture content. To cause uniform vaporization throughout all parts of the articles, means for agitating them is provided. .The vaporization of the moisture tends to build up a pressure within the chamber and therefore the chamber is pro- The only loss of heat vided with a vent of suicient size to prevent any appreciable rise in pressure within the chamber by permitting the vapor to escape from the chamber as fast as it is generated. Thus practically all of the heat generated within the chamber is utilized for vaporization of the moisture content of the articles except for the small radiation loss of the drier.
As shown in the drawings, the preferred embodiment comprises a base structure I having a narrower upright portion II supporting a chamber structure, indicated generally at I2. The chamber structure I2 preferably is of cylindrical form comprising a peripheral wall I 3, a front Wall I4, and a rear wall I5. These walls are of heat insulated construction and for this purpose may comprise an outer sheet metal facing I8 (see Fig. 2) and a sheet metal liner I'I spaced apart and filled with heat insulating material I8 such as rock wool or the like.
The source of heat preferably comprises an electrical heating element, indicated generally at 20, located within the chamber. In order to effect drying rapidly, the heating element 20 is preferably spread over a relatively large area within the chamber. Such spreading of the heat element furthermore tends to make the temperature throughout the chamber uniform. 'I'he spreading of the heat element also permits the use of an element of relatively large size or capacity so that for a given rate of heating a lower operating temperature of the element is obtainvable than if the heat element were of compact form. In the case of drying fabrics, such lower operating temperature has two very distinct advantages. One is that the lint from the fabrics being dried will not be ignited by an intense temperature in the element, and second that the danger of scorching the fabric is minimized.
To these ends the heating element is preferably made of a resistance material of strip form, or in the form of a rod such as that known in the trade as a Calrod, arranged in a series of parallel portions. In the present instance the Calrod is bent, as at 2| (see Fig. 4), to provide a series of Us extending parallel to the axis of the cylinder chamber and arranged in an arc adjacent the peripheral wall of the chamber in the upper part thereof. The Calrod is supported by a plurality of clips 22 attached to the intermediate portion of each U and carried by the upper portion of the rear wall I of the chamber structure. In order to facilitate installation of the heating element or repair thereof, the upper portion of the rear wall I5 of the chamber structure may be made in a separate piece, as shown in Fig. 5, and attached to the peripheral wall I3 as bymeans of screws 23. The heating element may thus be assembled on the upper portion of the rear wall and the latter then assembled in place on the rest of the chamber structure.
In order to control the heat of the heating element, a thermostat 24 may be provided, such thermostat preferably extending parallel to the U-shaped portions of the heating element at the top of the chamber structure. Since different fabrics have different temperatures above which they should not be heated without injury, the thermostat 24 is preferably of the adjustable type. For this reason the thermostat is preferably mounted on the removable upper portion of the rear wall I5 and has an adjusting member 25 on the outer face of said wall.
In order that the articles may be dried uniformly, and in order to facilitate vaporization of the moisture content thereof, means for agitating the articles during the course of drying is provided. In the present instance the agitating means comprises a rotatable drum or basket, indicated generally at 30, mounted within the cylinder concentrlcally therewith. The basket or drum is of such dimension that its peripheral wall is spaced from the peripheral wall of the chamber structure and in such space the heating element 20 is located. The drum or basket 30 is of foraminous construction and preferably is made of perforated sheet metal. In order to cause agitation of the articles placed Within the drum. radial vanes 3l are mounted on the periphery of the drum to extend radially inward therefrom. In the present instance three such vanes are provided and they extend from one end Wall of the basket to the other, thus rigidly reenforcing the basket.
When articles are placed within the basket, rotation of the drum causes the articles to be lifted up by the vanes, and as they approach the top, the articles slide off the vanes and spread out across the drum so that all parts thereof are subjected to the heat from the heating element 20.
To center and rotate the drum, it is preferably provided with a spider 32 on its rear face, the arms of which extend and are connected to the vanes 3 I. The spider is provided with a hub portion 33 (see Fig. 3) rigidly connected to the in-l ner end of a shaft 34 journaled in a bearing member 35 mounted on the rear wall I5 of the chamber structure. gaging the hub 33, a cone-shaped perforated metal guard 36 may be mounted over the hub.
The shaft 34 extends through the rear wall I5 of the chamber structure and is connected at its outer end to a driving means. In the preferred construction the outer end of the shaft -34 carries a sprocket 40 meshing with a chain 4I extending downwardly at the rear of the casing structure and driven by speed reducing gearing, indicated generally at 42, and an electric motor 43 mounted withinthe base structure I0. A removable guard or casing 44 is preferably placed over the chain. In removing the upper portion of the rear 'wall I 5, the casing 44 and the sprocket 40 may be first removed, the drum being temporarily supported through the front of the chamber structure, so that the bearing 35 may be slid rearwardly on the shaft 34. The upper portion of the rear wall may lthen be readily removed.
In the method of drying employed in the present drier, all the heat generated by the heating element 2U, except for such small portion as may be radiated from the chamber structure, is utilized for causing vaporization of the moisture content of the articles. Because of the large volumetric expansion of water when vaporized, a
' lpressure would be built up within the chamber .unless it were freely vented. Since it is the purpose of a drier to remove the moisture content of the articles being dried, the chamber structure is vented so that the vapor as fast as it is generated may force itself out of the chamber and prevent any appreciable rise in pressure Within the chamber. is provided With an opening comprising a slot 50 (see Fig. 2) which in the present instance extends transversely across the chamber structure for substantially the full Width thereof. The dimensions of the slot 50 are calculated so that To prevent the fabrics from en-v To this end the chamber the vapor generated within the chamber will force itself out through the slot 50 without causing any building up of pressure within the chamber. At the same time the slot is made no larger than is necessary from a practical standpoint in order that no air may enter the chamber through the slot.
Externally of the chamber structure the slot 50 may open into a condenser, indicated generally at I, which serves to condense the vapor after it leaves the chamber so that the humidity of the room in which the drier operates will not be undesirably increased. In Figs. 2 and 6 of the drawings I have illustrated a condenser of suitable construction, which comprises a box-like structure 52 provided with a plurality of heat radiating tubes 53 extending vertically through the box structure 52 to conduct air therethrough. The air passing through the tubes 53 cools them and fins or other well-known forms of heat absorbing structures are formed on the outer surfaces of the tubes within the box structure 52 so that the vapor is readily condensed. A manually operable tap 54 may be mounted in the lower portion of the condenser to drain oiI the water as it is condensed. The tap 54 also permits the escape of the air which initially filled the chamber and which is carried off with the vapor during the first part of the drying operation.
During the drying process, fabrics will give off a certain amount of lint. It is of course desirable to collect and dispose of such lint both because it should not be permitted to be carried into contact with the heating element, and because it is desirable to prevent its being mixed into the fabrics. For this reason, the invention includes a lint collecting and disposing means by which the lint is prevented from being continually thrashed around by the agitating means.
As shown particularly in Fig. 2, the chamber structure is provided with a downwardly opening pocket 60 preferably located at the bottom of the chamber. The pocket 60 extends the full width of the chamber, and one of the chamber walls leading toward the pocket is formed on a tangent so that the lint within the chamber will be swept into `the pocket 60. In the present instance where the drum or basket 30 is rotated in a counterclockwise direction, -as shown by the arrow in Fig. 2, the left hand wall of the pocket has a tangential relation to the cylindrical chamber, as indicated at 6|. The side walls of the pocket 60, as well as the tangential portion 6|, are of insulated construction similar to that of the walls of the chamber structure so that r the va'por will not tend to condense thereon and mat the lint.
In order to dispose of the lint collected in the pocket 60, the bottom wall of the pocket is made in the form of a downwardly opening hinged door 62, pivoted as at 63 (Figs. 2 and 3). In the base of the machine is a removable container in the form of a drawer 64 to receive the lint as it drops from the pocket 60. The door 62 is rigid with its pivot 63 which extends through the front wall and on its outer or forward end is mounted a handle 63 by which the door 62 may be manually opened. In order to keep the door normally closed, torsion springs 66 (see Fig. 3) may be mounted on the pivot 63 at each end thereof.
To facilitate the removal of the lint from the pocket 68 and its-disposa1 into the drawer 64, an air blast is provided for blowing the lint downwardly out of the pocket 60. To this end a shaft extension 'I0 is mounted in line with the shaft of the motor 43 and a fan 1I is carried on the shaft extension 10. The fan 1I is mounted in a tubular air duct 12 having its intake at the front face of the machine. The intake is preferably provided with a screen 13. The tubular air duct 12 extends rearwardly and thence upwardly, as at 14, alongside the pocket 60. At its upper end, the passage is provided with a slot 15 opening into the pocket 60. The tangential portion 6I of the adjacent chamber wall extends over the slot and directs the air blast downwardly toward the door 62. Thus when the fan 1I is operating and the door 62 is open, the air blast forces the lint downwardly into the drawer 64.
Since the air blast is needed only when the door 62 is open and since the mode of operation of the machine is such that air should not be permitted to enter the drying chamber, the fan is interlocked with the door -62 so that the former will operate only when the latter is open. To this end the shaft extension 10 and the motor shaft are provided with cooperating clutch parts adapted to' be connected as an incident to opening the door 62. As shown in Fig. 3 the clutch parts are indicated at I6 and 11 and a bell crank 18 is provided for shifting the clutch member 16 into and out of engagement with the clutch member 11. The bell crank 18 is connected by a rod I9 to the door. Thus when the door 62 is manually opened by the handle 65, the rod 19 and the bell crank 18 cause the clutch parts to engage and the fan to be operated.
In order to provide access to the interior of the chamber, a door 80 is provided which is located centrally of the front wall I4 of the chamber structure, and a centrally located aperture 8| is provided in the rotatable drum or basket 30. 'Ihe door 80 is preferably of circular construction and is provided with a lip 82 overlapping the front face of the wall I4, and a flexible sealing strip 83 is interposed between the wall I4 and the lip 82 to securely seal it when the door is closed. The door 8|) is also of heat insulated construction. In order to prevent the articles in the rotatable basket from being tumbled out through the aperture 8| and getting caughtl between the basket and the xed wall I4 ofr the chamber structure, the door 80 is of sufficient depth to extend inwardly and form a plug or closure loosely fitting in the aperture 8|. The door is mounted on a hinge 84 of a well-known type suitable for `such a construction and is adapted to be securely held in its closed position by a manually operable latch 85.
In the operation of the drier, the door 8D is thrown open and the articles to besdried are placed in the drum 38 and the door is closed. The motor 43 is then started and the drum is vthereby caused to be rotated. The articles,
which naturally tend to fall to the bottom of the drum, are carried upwardly by the vanes 3|. As they reach the upper portion of the chamber where they are close to the heating element 20, they fall or slide oiI the vanes 3| and in vsuch falling spread out loosely so that all parts thereof are uniformly subjected to the heat. The heat causes the moisture content of the articles to be rapidly vaporlzed, thus drying out the articles. The heating element 20 is of sufi'icient capacity and is spread out sufficiently to produce a substantially uniform temperature throughout the chamber of 212 Fahrenheit or somewhat above, which of course is the vaporization temperature of water at atmospheric pressure. Because o! the fact that the heating element is spread over a relatively large area and consequently is of considerable size and capacity, it is unnecessary to have the heating element operate at a very high temperature. Thus the articles in passing close to the heating element are in no danger of being scorched. Moreover, by means oi adjusting the thermostat 24, the heat may be regulated to such temperature as will prevent 'injury to diiierent kinds of fabrics.
The generation of vapor within the chamber of course would tend to build up a pressure therein i! the chamber were sealed. Since the purpose of the drier is to remove the moisture content of the articles, this tendency to build up pressure is utilized by letting the vapor as it is generated force itself out through the slot 50. Thus no appreciable increase in pressure occurs within the chamber, and the vapor is disposed of substantially as fast as it is generated. The slot 5I), however, is only koi sufficient size to carry ori the vapor so that no air will enter into the chamber through the slot. By preventing any substantial entryv of air into the chamber, the heat is not wasted by heating such air, and substantially the entire quantity of heat generated by the heating element 20 is utilized for causing vaporization of the moisture. The chamber is of course lled with air initially but such air will be rapidly carried out of the chamber through the slot 5U with the ow of vapor.
As the vapor leaves the slot 50 it enters the condenser 5l where it is liquefied and may be drawn oi through the tap 54. The tap 54 also permits the escape of the air which is initially in the chamber and is carried ofi' with the vapor.
During the agitation of the `fabrics by the rotatable drum 30, a certain amount of lint is formed. Such lint is swept into the pocket 60 past the tangential wall portion 6I and is collected in a mass resting on the door 62. After the articles are dry and removed from the chamber, the door 62 may be opened by turning the handle 65 and the mass of lint will drop into the drawer 64. To clear out all the lint from the pocket 60, the downwardly directed blast of air entering the pocket through the slot l5 will completely discharge all the lint into the drawer 64. The fan 1i for producing such blast of air is y operated only at such time as the door 62 is open because of the interlock between the door and the clutch connecting the fan with the motor. The torsion springs 66 tend to keep the door 62 closed, thereby preventing any substantial quantity of air from entering 'the chamber through the pocket 60. While the pocket will collect the lint throughout the drying cycle, it is preferred to operate the discharge of the lint into the drawer only at the conclusion of the drying cycle. However, it may be operated during the drying cycle if desired.
From the foregoing description it will be apparent that I have provided a novel drierA utilizing substantially all of the heat generated within the chamber, for the purpose of evaporating the moisture content of the articles to be dried. In other words, since no air is permitted to enter the drying chamber during the drying cycle, no heat is lost in heating up such air. The only loss of heat is the minor loss through radiation from the drier as a whole, which loss is reduced to a minimum by the heat insulated construction of the drier. By such eiilcient use of the heat generated, the articles may be dried in a relatively short space of time and in a temperature which tends to sterilize the articles. 'I'he tumbling or agitation of the fabrics during the drying cycle leaves them in a Iluiiy, unmatted condition. This is particularly desirable with articles such as bath towels or the like.
Since no air is permitted to ente'r the drying chamber during the drying cycle, and since the heat is not imparted to the articles by means of heated air, the rate of drying is not dependent upon the humidity conditions oi the air in the room in which the drier operates. For the same reason the rate oi.' drying is not to any substantial extent dependent upon the temperature of the room. A further advantage arising because of the same reasons is that the temperature of the room is not raised because of any large volume of heated air being discharged into it, nor is the room atmosphere raised in humidity to any apperciable extent. because of the fact that the water vapor as it is discharged from the chamber is condensed. The use of the large heating element prevents excessive temperatures such as might injure fabrics if they are exposed thereto too long, and would likewise reduce the quantity of lint formed during the drying, as well as any chance of burning what little lint is formed should it be blown into direct contact with the heating element. Moreover, what little lint is formed is readily collected in the pocket 60 and is discharged into the drawer 64 so that there is no danger of accumulating lint within the chamber.
It will also be apparent that I have provided a novel method of drying articles such as fabrics.
I claim as my invention: l. A drier of the character described comprising, in combination, a cylindrical chamber, a drum wiihin the chamber to receive the articles to be dried and to agitate them, and `a heating element located within the cham-ber and arranged in an arc extending circumferentially around the drum to provide a source of heat extending over a large area, said element being rigidly secured to an adjacent portion of one wall of the chamber and said portion being detachably secured to the chamber structure so as to be readily removable and thereby provide for removal of the heating element, said chamber being vented for removal of the vapor generated during the drying.
2. A drier for fabrics comprising, in combination, a cham-ber to receive the moist fabrics, heat generating means within tht,` chamber, means for agitating the fabrics within the chamber, said chamber having a pocket in its peripheral wall located adjacent the bottom of the chamber to collect lint from the fabrics and prevent its circulation within the chamber, a removable container adjacent said pocket, a manually operable door arranged to deposit the lint collected by said pocket in said container, and air blast means connected to said door and rendered operableas an incident to the opening of said door to blow the lint from said pocket into said container.
3. A drier for fabrics comprising, in combination, a chamber, heat generating means within the chamber, a rotatable drum to receive the fabrics for agitating them, a pocket in the peripheral wall of the chamber` having a generally tangential opening whereby the lint from the fabrics will be swept into said pocket, a door 'in said pocket, a removable container adjacent said door ,and means iorconnecting said driving means to receive the lint upon opening the door, .and air blast means opening into said pocket and directed toward said door, said air blast means connected to said door and rendered operable as an incident to opening said door whereby the lint collected in said pocket is blown through said door and into said container.
4. A drier for fabrics comprising, in combination, a chamber to receive the moist fabrics, heat generating means within the chamber, means for agitating the fabrics during the course of drying, a pocket in the peripheral wall of the chamber to receive the lint from there. fabrics and having an opening, a removable container adjacent said opening, a door for said opening, a fan, an air passage from said ian to said pocket to conduct a blast of air from said fan to said pocket to blow the lint in said pocket through said opening and into said container, driving means for said Ian,
with said fan interlocked wlthsaid door whereby said air blast will occur only when said door is open. A l
5. A drier for fabrics comprising, in combination, a chamber, heat generating means within the chamber, a rotatable drum to receive the moist fabrics, means in the wall of said chamber to collect lint from said fabrics and provided with an opening, movable closure means for said opening, a motor for driving said drum, a fan mounted coaxially with the motor shaft, an air passage leading from said fan to said lint-collecting means to conduct a blast of air thereto to blow the lint through said opening, a clutch for connecting said fan to the motor shaft, and an interlock connecting said clutch with said closure means.
LEO M. ONEIIL.