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Publication numberUS3309783 A
Publication typeGrant
Publication dateMar 21, 1967
Filing dateMar 9, 1964
Priority dateMar 9, 1964
Publication numberUS 3309783 A, US 3309783A, US-A-3309783, US3309783 A, US3309783A
InventorsWorst Joseph C
Original AssigneeGen Electric
Export CitationBiBTeX, EndNote, RefMan
External Links: USPTO, USPTO Assignment, Espacenet
Clothes drying machine having reversing drum drive means
US 3309783 A
Abstract  available in
Previous page
Next page
Claims  available in
Description  (OCR text may contain errors)


R E o w W w H m g o H I United States Patent Cfifiee 3,309,783 Patented Mar. 21, 1967 3,309,783 CLOTHES DRYING MACHINE HAVING REVERSENG DRUM DRIVE NEANS Joseph C. Worst, Louisville, Ky., assignor to General Electric Company, a corporation of New York Filed Mar. 9, 1964, Ser. No. 350,344 3 Claims. (Cl. 34-48) This invention relates to clothes drying machines, and, more particularly to such machines of the type which have a basket rotating on a non-vertical axis, in which the clothes to be dried are tumbled in the basket during the drying operation.

The conventional approach to the tumbling of clothes in such baskets is to rotate the clothes basket continuously in one direction at a rate of speed which is appropriate to effect a tumbling pattern for the clothes therewithin. This is, of course, a simple type of structure, one which causes relatively little wear and tear on the parts of the machine. However, when a large load of clothes, with many pieces, is put into the drum, or basket, of a clothes dryer to be tumbled, it often occurs that, because of the large quantity of clothes tumbling in a relatively restricted space, an undesirable amount of tangling occurs. When this happens, the effectiveness of the dryer is impaired; in addition, it is disagreeable for the operator to find the clothes tangled with each other when she wishes to remove the clothes from the dryer at the end of an operation.

This tangling action can best be prevented by reversing the direction of rotation of the clothes basket on a cyclic basis, so that throughout a drying operation the basket rotates first in one direction and then in the other. While this tumbling approach is effective to prevent tangling of large loads, it provides virtually no improvement in average and small loads. Also, it will readily be seen that the cyclic reversal of a relatively large clothes drum with clothes therein constitutes quite a strain on the parts of the drying machine.

It is, therefore, an object of my invention to provide an improved clothes dryer wherein the operator may elect, depending upon the size of the clothes load to be dried, whether a cyclic reversal of the basket rotation takes place or whether it is precluded from taking lace.

In one aspect of my invention, I provide a clothes drying machine wherein clothes are dried in a basket which rotates on a substantially non vertical axis, suitable heating means being provided for heating clothes in the basket so as to cause them to dry. The basket is rotated alternatively in either one direction or the other by suitable drive means. The change from one direction to the other may be effected cyclically by suitable reversing means which cause the drive means to reverse the rotation of the basket cyclically during a drying operation. Suitable means are provided to prevent this cyclic reversal from taking place, and manual means are provided so that the operator may selectively, depending upon the size of the clothes load, either provide unidirectional basket rotation or cyclic reversal.

The subject matter which I regard as my invention is particularly pointed out and distinctly claimed in the concluding portion of this specification. My invention, however, both as to organization and method of operation together with further objects and advantages thereof, may

best be understood by reference to the following description taken in conjunction with the accompanying drawmgs.

In the drawings, FIGURE 1 is a side elevational view of a clothes dryer incorporating my irnproved tumbling control arrangement, the view being partly broken away and partly sectionalized in order to illustrate details;

FIGURE 2 is a view along line 2-2 in FIGURE 1 showing a portion of a reversing mechanism, which may be used in the operation of my invention, arranged to provide a first direction of rotation;

FIGURE 3 is a view similar to FIGURE 2 showing the parts arranged to provide the other direction of rotation; and 7 FIGURE 4 is a schematic illustration of an improved control circuit incorporating my invention.

Referring now to FIGURE 1, the machine illustrated is a domestic clothes dryer generally indicated by the numeral 1. Dryer 1 is provided in the usual way with a cabinet 2 having a front door 3 to provide access to the interior of the cabinet for loading or unloading clothes. Provided on the top wall 4 of cabinet 2 is a control panel 5 which may in the conventional way include controls 6 mounted in the panel. By operation of controls 6, the machine may be caused to start and automatically proceed through a cycle of operations.

Within cabinet 2, there is provided a clothes tumbling basket, or drum, 7 mounted for rotation on a substantially non-vertical axis which, as in the present case, is preferably horizontal. Drum '7 is substantially cyclindrical in shape, having a first cylindrical wall portion 8, second and third outer cylindrical wall portions 9 and 1t located respectively adjacent the front and back of the drum, a front wall 11, and a back wall 12. Outer wall portions 8, 9 and 1d are imperforate over their entire length so that the outer shell of the basket is imperforate. On the interior surface of central portion 8 there may be provided a plurality of clothes tumbling ribs 13 so that clothes are lifted up when the drum rotates and then tumble back down to the bottom of the basket. This provides continuous flexing of the clothes and changing of the exposed surfaces thereof.

The front of drum 7 may be rotatably supported within outer casing 2 by suitable idler wheels, one of which is shown by the numeral 14. These Wheels are rotatably secured to the top of a member 15 which extends up from base 16 of the machine. Wheels 14 are disposed beneath the drum in contact with portion 9 thereof so as to support portion 9 on each side to provide a stable support.

The rear end of drum 7 receives its support by means of a stub shaft 17 extending from the center of wall 12. Shaft 17 is secured within a bearing 18 formed in a bafiie 19 which, in turn, is rigidly secured to the back wall 20 of cabinet 2 by any suitable means such as, for instance, welding at a number of points 21. With the arrangement shown, the basket may rotate on a horizontal axis, with rollers 14 providing the front support and stub shaft 17 within bearing 18 providing the rear support. In order to provide for the flow of a stream of drying air through the drum, the drum is provided with a central aperture 22 in its front wall 11 and with an opening in the form of a plurality of perforations 23 in its rear wall 12, the perforations in the present case being formed to extend around the rear wall in an annulus.

As has been stated, baflde member 19 is rigidly secured to rear wall of cabinet 2. Bafiie member 19 also serves to support heating means 24 which includes two electrical resistance heating elements appropriately insulated from the bafile member. The elements may be annular in shape so as to be generally cmxtensive with perforations 23 in drum 7. A bafile member 25 is rigidly secured to the back wall 12 of the drum outside the ring of perforations 23 and within the stationary baffle 19, so that an annular air inlet 26 is in effect formed by baflles 19 and 25. In this manner a passage is formed for air to enter annular inlet opening 26 between the baffles, pass over the heater 24, and then pass through openings 27 formed in baffle 25 to the interior of drum 7.

The front opening 22 of the drum is substantially closed by means of a stationary bulkhead generally indicated by the numeral 28. Bulkhead 28 is made up of a number of adjacent members including the inner surface 29 of access door 3, a stationary frame 30 for the door formed as a flange of front wall 31 of the cabinet, the inner surface member 32 of an exhaust duct which is formed by the cooperation of member 32 with the front wall 31 of the cabinet, and an annular flange 33 mounted on frame 30 and on the duct wall. It will be noted that a suitable clearance is provided between the inner edge of the drum Opening 22 and the edge of bulkhead 28 so that there is no rubbing between the drum and the bulkhead during rotation of the drum. In order to prevent any substantial air leakage through opening 22 between the interior and the exterior of the drum, a suitable ring seal 34, preferably formed of felt-like material, is secured to flange 33 in sealing relationship with the exterionwall surface of drum wall 11.

Front opening 22, in addition to serving as part of the air flow path through the drum, also serves as a means whereby clothes may be loaded into and unloaded from the drum. Door 3, whose inner surface forms part of the bulkhead closing the opening, is mounted on cabinet 2 so that when the door is opened clothes maybe inserted into or removed from the drum through the door frame 30. It will be noted that the door includes an outer flange imperforate section 35 and an inwardly extending hollow section 36 mounted on the flat outer section. Hollow section 36 extends into the door frame 30 when the door is closed, and the door surface 29 which comprises part of the combination bulkhead 28 is actually the inner wall of the hollow section.

The air outlet from the drum is provided by a perforated opening 37 formed in the inner wall 29 of hollow door section 36. The bottom wall section of door 3 and the adjacent wall of door frame 30 are provided with aligned openings 38 and 39, opening 39 providing the entrance to the duct 40 formed by the cooperation of member 32 with front wall 31. As shown, a lint trap 41, which may comprise a fine mesh bag, is preferably positioned in the exhaust duct 40 at opening 39, the bag being supported by the frame 30.

Duct 40 leads downwardly to an opening 42 formed in the member 15 which supports wheels 14. Opening 42 constitutes the inlet to a blower member 43, contained within a housing 44 and directly driven by an electric motor 45. The blower draws ambient air in over the heater 24, then through the basket, then through the door 3 and the duct 40, and then into the blower. From the blower the air passes through any appropriate duct (not shown) out of cabinet 2 so as to be exhausted from the machine.

In addition to driving blower 43, motor 45 constitutes the drive means for effecting rotation of basket 7. In order to effect this, motor 45 is provided with a shaft 46 having a small pulley 47 formed at the end thereof. A belt 48 extends around pulley 47 and also entirely around the cylindrical wall section 8 of drum 7. The relative circumferences of pulley 47 and wall section 8 cause the drum to be driven by the motor at a speed suitable to effect tumbling of clothes therein. In order to effect proper tensioning of belt 48, there may be provided a suitable idler assembly 49 secured on the same support 50 which secures one end of the motor. Thus, the air is pulled through the drum and at the same time the fabrics in the drum are tumbled. When the air is heated by heating elements 24, the heated air passing to the drum causes vaporization of moisture from the clothes. The vapor is carried off with the air as it passes out of the machine.

Suitable means are provided for causing motor 45 to effect rotation of basket 7 in the direction opposite to that normally provided by operation of the motor and transmission of motion to belt 48 by pulley 47. In order to do this, an assembly, generally indicated by the numeral 51, is provided under the control of a member 52 whose position in turn is controlled by a solenoid 53. The operation of this particular type of reversing mechanism is completely described and claimed in Letters Patent No. 3,211,015 issued to John Bochan on Oct. 12, 1965, and assigned to General Electric Company, assignee of the present invention. That application describes in complete detail how, when solenoid 53 is de-energized as shown, pulley 47 causes movement of belt 48 in a first direction (see FIGURE 2), and when the solenoid 53 is energized the pulley 54 extending from assembly 51 moves into engagement with the belt 48, at the same time forcing the belt out of engagement with pulley 47 (see FIGURE 3). Pulley 54 rotates in the opposite direction to pulley 47 and therefore causes the belt to move in the opposite direction. Thus, cyclic energization and de-energization of solenoid 53 is effective to cause, cyclically, rotation of drum 7 first in one direction and then the other. It will be understood that the particular reversing mechanism shown is selected only for purposes of illustration, and that any suitable reversing system may be utilized, including the reversible motor.

In summary then, when solenoid 53 is de-energized a first direction of rotation of the basket is provided, when the solenoid is energized the opposite direction of rotation is provided, and when the solenoid 53 is cyclically energized and de-energized the basket rotates first in one direction and then the other.

The operation of dryer 1 is controlled by the system shown in the circuit diagram of FIGURE 4. As shown therein, the entire control system of the machine may be energized across a three-wire power supply system which includes supply conductors 55 and 56 and a neutral conductor 57. For domestic use, conductors 55 and 56 will normally be connected across a 220 volt power supply, with 110 volts appearing between the neutral line 57 and each of the conductors and with the neutral line being at ground voltage.

Motor 45, connected between conductors 55 and 57, is a single-phase induction-type motor having a main winding 58 and a start winding 59, both connected at a common end to a conductor 60. Through a conventional door switch 61 (which is cloesd when door 3 is closed and is opened when the door is open) conductor is connected to conductor 57. Start winding 59 is connected in parallel with main winding 58 under the control of a speed responsive device, such as that shown at 62 which is schematically shown as connected to rotor 63 of the motor. The speed responsive device 62 controls a switch 64 which is engageable with either a contact 65 or a contact 66. Switch 64 is engaged with contact 65 when the machine is at rest and moves into engagement with contact 66 as the motor comes up to speed. It can readily be seen that engagement with contact 65 connects the start winding in parallel with main winding 58, while movement of switch 64 away from this position opens the start winding. Thus, as rotor 63 comes up to speed the start winding becomes de-energized, and the motor then continues to run on the main winding 58 alone.

The starting of the motor is provided by a manually operable switch 67 which may, for instance, in the structure of FIGURE 1, be moved to its closed position by pulling out on control member 6. Switch 67 connects the motor to supply conductor 55, and is normally biased to the open position shown. When member 6 is pulled out, energization of the motor is provided and within less than a second then, under normal circumstances, the motor comes up to speed so that switch 64 engages contact 66. As a result of this movement of the centrifugally operated switch 64, the main winding 58 of motor 45 continues to be energized by a bypass around switch 67 when member 6 is released and the switch 67 opens.

A sequence control mechanism for the machine is provided which includes a timer motor 68 together with earns 69, 70 and 71 controlled thereby. Switches 72, 73 and 74 are respectively controlled by the cams 69, 70 and 71. In order to put the machine into a position where a cycle of operations may take place, the cams 'are manually rotated to a starting position wherein all three of their control switches are closed. This is conventionally done by rotating member 6 to the appropriate position. When the switches are closed, then the ene'rgization previously described of motor 45 may take place. In addition, the timer motor 68 is energized through switch 72, after the motor comes up to speed so that mechanism 62 closes a second centrifugal switch 75. The closure of switch 73 provides for energization of heater 24 across conductors 55 and 56, that is, across the full 220 volt source of supply. In adidtion, it is conventional in the art to supply one or more control thermostats, such as that indicated by the numeral 76, so that an appropriate control may be provided for the heat.

The arrangement shown constitutes one means of providing a drying operation of a predetermined length of time, that is, the sequence control mechanism comprised of timer motor 68, and the cams and switches controlled thereby, constitutes a control mechanism for providing a drying operation. It will be understood that this merely represents a typical control mechanism, and that other control mechanisms, either for providing pure timed operations such as is involved here, or for providing an operation which is responsive to other factors such as dryness of the clothes, may be used with equal success. In the present case, it will be understood that the member 6 is initially rotated at predetermined amount so that, with all three switches closed, it will take a certain amount of operation of the timer motor 68 and rotation of cams 69, 70 and 71 before they reach the point where they open their switches 72, 73 and 74 to end the drying operation.

In addition, there is provided 'across the conductors 55 and 57 a second timer motor 77 which may be energized when a switch 78 is closed. Switch 78 is ganged to a switch 79, with both of them being controlled by a manual member 80 provided on the front of control panel 5, as shown, so as to be selectively operable by an operator. The timer motor 77 operates a cam 81 which in turn controls a switch 82.

Solenoid 53, which controls the rotation-reversing mechanism 51, is in series with switches 79 and 82, so that when both switches are closed the solenoid is energized to" cause basket rotation in one direction; when either or both of the switches is opened, the solenoid is de-energized and rotation occurs in the other direction as previously described. Timer motor 77; when it is energized by closure of switch 78, is arranged so that it keeps switch 82 closed for an appropriate period, and then open for a like period. In practice, I prefer to have the periods exceed 30 seconds so as to minimize the wear on the machine; in fact, even periods of three minutes have been found to provide adequate untangling characteristics. In other words, there is a cyclic opening and closing of switch 82 and therefore a cyclic energization and de-energization of solenoid 53. This, in turn, results in a cyclic reversal of the direction of rotation of basket 7. When switches 78 and 79 are opened, the timer motor 77 is de-energized and the solenoid 53 is de-energized, thus ensuring rotation of the basket in a particular direction on a continuous basis.

As described above, continuous rotation of the basket 7 in the same direction with large loads tends to result in tangling, with a resultant decrease in the effectiveness of the drying operation, and with difiiculty being caused to the operator in separating the clothes as they are pulled out of the machine. Thus, appropriate markings (not shown) may be provided on the control panel 5 adjacent member 80 so as to indicate that switches 78 and 79 are to in the position shown for a regular load, and to be in the closed position for a large load. What this does, then, is to provide continuous operation in the same direction for a regular load and cyclic reversal, at the selected intervals, of the direction of basket rotation when 'a large load is to be dried.

Thus, my invention provides an arrangement wherein the special provisions desirable for proper tumbling of large loads are provided, yet smaller loads may be tumbled without the wear and tear on the machine which results from a cyclic reversal being provided at all times even when it is not necessary.

While in accordance with the patent statutes I have described what at present is considered to be the preferred embodiment of my invention, it will be obvious to those skilled in the art that various changes and modifications may be made therein without departing from the invention, and it is therefore aimed in the appended claims to cover all such equivalent variations as fall within the true spirit and scope of my invention.

What I claim as new and desire to secure by Letters Patent of the United States is:

1. A clothes drying machine comprising:

(a) a clothes basket rotatable on a substantially nonvertical axis;

(b) heating means for heating clothes in said basket to cause drying thereof;

(c) drive means for rotating said basket alternatively in either one direction or in another direction;

(d) control means for providing a drying operation during which said heating means and said rotating means are operated;-

(e) reversing means for cyclically causing said drive means to reverse the rotation of said basket during an operation;

(f) and manual means for selectively actuating said reversing means, so that a user of said drying machine may select unidirectional or cyclically reversing rotation of said clothes basket.

2. A clothes drying machine comprising:

(a) a clothes basket rotatable on a substantially nonvertical axis;

(b) heating means for heating clothes in said basket to cause drying thereof;

(c) drive means for rotating said basket alternatively in either one direction or in another direction;

(d) control means for providing a drying operation during which said heating means and said rotating means are operated;

(e) reversing means for cyclically causing said drive means to reverse the rotation of said basket during an operation, said reversing means comprising an electrical element causing rotation to be in one direction when energized and rotation to be in the other direction when de-energized, a switch in series with said electrical element, and a timer effective when energized to cycle said switch open and closed;

(f) and manual means for selectively energizing said timer, so that a user of said drying machine may select unidirectional or cyclically reversing rotation of said clothes basket.

3. The apparatus defined in claim 2 wherein said drive means comprises a unidirectional motor, and a transmis- 7 8 trical element controlling said transmission to determine 2,906,035 9/1959 Moss 3445 the direction of output rotation of said transmission. 2,961,776 11/ 1960 Hughes 34--133 3,161,481 12/1964 Edwards 3445 References Cited by the Examiner UNITED STATES PATENTS 5 FREDERICK L. MATTESON, JR., Primary Examiner.

2,283,612 5/1942 Perry 68-19 JOHN CAMBY: Exammer- 2,643,463 6/1953 Grantham 3445 D. A. TAMBURRO, Assistant Examiner.

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U.S. Classification34/553, 34/547, 34/534
International ClassificationD06F58/04, D06F58/08, D06F58/28
Cooperative ClassificationD06F58/08, D06F58/28
European ClassificationD06F58/28, D06F58/08