US2782620A - Water level control for automatic washing machines - Google Patents

Description

Feb. 26, 1957 w. J. ROTH El'AL WATER LEVEL CONTROL FOR AUTOMATIC WASHING MACHINES Filed Oct. 9, 1952 5 Sheets-Sheet l M W m W W W. H B A r 0 Mx w we M a r e\ w 21 n P w 1 V I 4 Z 2 H 2 2 n. .2 K. 9 v F 4 O W. 2 o v m M u. a i \t W. J. ROTH EI'AL Feb. 26, 1957 WETER LEVEL CONTROL FOR AUTOMATIC WASHING MACHINES Filed Oct. 9, 1952 3 Sheets-Sheet 2 HE: E

I N VE NTOR$ WAZ rm J Bum JANA! 2. Farm ATTORNEY! Feb. 26, 1957 w. J. ROTH ETAL 2,782,620

WATER LEVEL CONTROL FOR AUTOMATIC WASHINGMACHINES Filed Oct. 9, 1952 s Sheets-Sheet 3 INVENTORJ Wm re: J. Porn Jane! E. Fasrig BY cw bv ATTORNEY! United States atent O WATER LEVEL CONTROL FOR AUTOMATIC WASHING MACHINES Application October 9, 1952, Serial No. 313,945 4 Claims. (Cl. 68*12) This invention relates to improvements in domestic clothes washing machines of the so-called automatic type wherein the clothes are washed, rinsed and spin-dried in an automatically controlled sequence of operations.

In one form,'such as exemplified in the George P. Castner Patent No. 2,513,844, machines of this type'comprise an outer casing and an inner frame and Works as- 'sembly whichincludes an imperforate tub for containing the clothes and the water for washing and rinsing. In such machines provision is made for gyration of the inner works assembly as the spin tub is rotated with an unbalanced'load, and for this purpose there is some form of yieldable or movable support connection between the outer stationary casing and theinner gyrating assembly, about which support the latter assembly may gyrate. In addition, there is also provided means for snubbing and resisting such gyration in order to confine it to a reasonable amount. The clothes are actually Washed in most cases by provision of an oscillating agitator within the spin tub and the sequential operations of washing, rinsing and spin-drying are automatically timed and controlled by a timer motor and switching system.

In another form these automatic clothes washing machines have a perforated spin tub, or spin basket, in which the clothes are'placed for washing and this perforated tub-operates within a larger, surrounding and water confining tub, but in any case the same sequential operations take place for washing, rinsing and spin-drying the clothes.

In such automatic'rnachines there arises a problem in that it is necessary for the tub to be filled with a working or washing level of water before the'agitating means is set in motion, since otherwise the clothes may be tangled and torn. Filling of the tub is accomplished by a water supply valve, or valves,*which is controlled by the timer motor, and operated for a definite period of time before the agitating means is set in motion, and under normal or most advantageous conditions this gives surficient protection for the clothes. Difliculty arises, however, from the wide variations in water pressures which are encountered not only in different parts of the country but in different parts of each city and at different times of the day. Oftenthe water pressure will drop so low that the opening of the valve for the set period of time will not provide suflicient water for washing the clothes without 'damage'thereto. Valves for this purpose have been designed which will-maintain a working level of water within five to'ten percent under Water'pressure variations of from between twenty and one hundred pounds, for example, but even this is not sufficient since there are locations in most citiesin which the water pressure willdrop even below thisminimum when lawns are being watered or when theload on the water system is higher than usual for other reasons. In such conditions it all too frequently. occurs that the agitating means will be set in motion before the water in the tub has built up to the desired level, with resulting damage to the clothes. In some instances also the operator of certain machines'may, instarting to wash, turn on only the hot water, and then when the machine reaches its rinsing cycles there will result an inadequate supply of water.

It is accordingly the primary object of our invention to provide means forsolving this problem by sensing'or measuring the weight of the water in the tub and actuat ing a control which will prevent the starting of the washing action, until the weight of the water in the tub has risen to a point corresponding to the existence of the de sired working level in the tub.

It is another object of our invention to provide, in conjunction with a washing machine having an outer stationary housing, or casing, and an inner frame and works assembly, a means for supporting the works assembly so that it may be deflected downwardly, with reference to the outer stationary casing, as the weight of the water in the tub increases and to then utilize this downward deflection for the control of the valve which supplies water to the tub, so that this valve is maintained in an open condition until the water level reaches the desired point.

These and other more detailed and specific objects-will be disclosed in the course of the following specification, reference being had to the accompanying drawings, in which Fig. 1 is a side elevation of one form of washing machine showing a portion thereof broken away in order to disclose interior details of construction and with one form of water level control therein.

Fig. 2 is a horizontal plan view of the base portion of the machine as viewed substantially along the line 2"'2 in Fig. 1. In this view there is also illustrated a line 11 substantially along which Fig. 1 is taken.

Fig. 3 is an enlarged detail sectional andelevational view of the lower lefthand portion of the machine as seen in Fig. 1.

Fig. 4 is a schematic and simplified diagram of one manner in which the water control may be connected into the electrical circuit of the machine.

Fig. 5 is an enlarged vertical cross sectional view through the lower part of a machine like that of Fig. I, but showing a variation in the support for the inner frame and works assembly, in which the weight of the water is measured at the center point about which said assembly gyrates, and showing also a slightly different form of switch for controlling the water level.

Fig. 6 is a vertical cross sectional view through the lower part of a machine of the type employing a perforated spin basket and illustrating another modification of the support between the inner works assembly and the outer casing by which the weight of the water is sensed and the water level controlled according to our invention.

It will at the outset be realized by those skilled in the art that'there are many constructions of automatic washing machines to which our invention may be applied by the provision of means for permitting vertical deflection of the inner works and tub assembly, by the weight of thewater accumulated in the tub, and then utilizing such deflection forcontrolling the water level. We do not, therefore, limit ourselves to the specific examples here shown, but for convenience in Figs. 1 through 4 we have shown a washing machine which is in general similar to that disclosed in detail in the earlier Castner Patent No. 2,513,844. This machine may be regarded as typical of that type of'automatic clothes Washer in which the clothes and water are contained within an imperforate, rotatably mounted spin tub which is arranged for rotation at a speed sufiicient to centrifugallyexpel the water when the washing andrinsing cycles are completed.

Referring then more particularly and by reference characters to Figs. 1 through 4, we illustrate therein a machine having a stationary outside frame or casing which encloses an inside frame and works assembly, desinated generally at 11. The latter assembly is supported for gyration about the vertical spin axis of the tub at a support point or movable support element 12, while the outside casing 10 includes the usual walled structure 13 in which there is a partition 14 forming the bottom of a splash tub 15. It will, of course, be understood that the specific details of this outside casing structure 10 are here immaterial, but it will be noted that the casing includes a marginal base channel 16 having inwardly turned, upper and lower flanges 17 and 18. Also as material to the understanding of our invention said casing structure 10 includes another stationary frame member 19 spaced upward some distance from the base channel 16.

The inner frame and works assembly 11 includes a rotary spin tub 20 having substantially imperforate and upwardly flaring side walls 21, so that upon rotation of the tub the liquid content thereof may be centrifugally driven up the walls and outwardly over the upper edge of the tub for discharge into the splash tub 15. The clothes are washed by means of an oscillating agitator 22 in the spin tub 20 and this assembly is carried upon a main vertical spindle unit 23 through which torque is transmitted for rotating the tub and power flows for oscillating the agitator. The mechanism by which these elements are driven is immaterial to an understanding of the present invention, but this mechanism is shown as including a lower element 24 from which there depends a pin forming the bearing point 12, resting in a resilient bearing 25 in a suitable bearing cup 26 to permit gyration of the entire inner assembly, as set forth in the Castner patent.

As stated hereinbefore, it is necessary that the cycle of operations of the spin tub and agitator be so related to the level of the water in the spin tub that the clothes will not be agitated with an insufficient volume of water and thereby become damaged. In Fig. l the numeral 27 indicates the desired or working level of water for the tub and it will, of course, be appreciated that this volume of water will have a very considerable weight. In accordance with our invention, therefore, this weight of the water is operatively arranged to downwardly defleet the inner frame and works assembly 11, with reference to the stationary outside casing 10, and the resulting movement controls the supply of water to the tub, as will now be described.

As one simple example of the manner in which this may be accomplished, we have shown the support point 12 as located upon a vertically movable support or connection between the assemblies 10 and 11, designated generally at 28. Said support 28 actually is a cross member extending between opposite sides of the base channel 16 and welded or otherwise fastened at one end 29 to that channel, as indicated in Fig. 2. Extending centrally from this cross member 28 is another frame member 30 which is welded or otherwise secured at 31 to the base channel 16. The free end 32 of cross member 28 extends loosely between the upper and lower flanges 17 and 18 of the base channel and as clearly shown it is narrower, measured vertically, than the space between said flanges. The arrangement is thus obviously such that this support structure 2830 may flex in a vertical plane from the points 29-31 with a resulting upward and downward movement of the free end 32 of member 28. Normally said end 32 is pulled upward against the upper flange 17 by a retractile coil spring 33 hooked at 34 to the adjacent corner 35 of the cross member and connected by means of an eye-bolt 36 to the frame member 19, so that the tension of the spring may be adjusted as will be readily appreciated.

Assuming the spring 33 to have been properly preloaded with the inner works assembly 11 in its dry condition, it follows that the support structure for this "structure 11 maybe caused todefiect downwardly as the weight of the water in the tub 20 increases, resulting in a measurable downward movement of the end 32 by the time that the water approaches the working level 27. This weight-induced, downward movement is then utilized for the actuation of an electrical switch 37, which in the present instance is shown as of a well-known micro-switch type having an actuating tongue or arm 38 overlying the lower flange 18 of base channel 16. The switch 37 is itself here shown as mounted on the moving end 32 of the support structure, although this showing is suggestive only and the switch might as well be mounted on the stationary part and the tongue 38 engaged in some fashion by the moving part of the assembly. In any case it is obvious that if the switch 37 is in one condition, in the normal or unloaded position of the parts shown in Fig. 1, then the downward deflection occasioned by the increasing weightof the water being added to the tub will positively adjust the switch to a different condition.

While there are various ways in which the switch 37 may be connected into the circuit for properly controlling the machine, we have in Fig. 4 illustrated a simplified schematic circuit wherein 39 designates the motor which drives the agitator 22 and which motor is connected to the supply conductors 40 and 41. Also here illustrated is a solenoid 42 which operates the clutch for engaging and disengaging the drive to the agitator and a part of the actual clutch appears at 43 in Fig. 1. Another solenoid 44 is also shown in Fig. 4 and the same is utilized for the control of the water valve which supplies the water to the spin tub 20 and which valve is, of course, not here shown since it is entirely conventional.

In this circuit the switch 37 is illustrated as of the single-pole, double-throw variety with the moving contact connected at 45 to one supply conductor 40, while the stationary contacts 46 and 47 are respectively connected to end terminals of the solenoids 42-44, the opposite terminals of which are connected to the other conductor 41. In the normal or unloaded condition of the machine the switch 37 closes the circuit to the valve solenoid 44, as illustrated by the solid line position of the moving contact, and under these conditions the water valve will be opened under the normal control of the automatic timing and switching system. Under these conditions, however, it will also be noted that the circuit to the clutch solenoid 42 is open so that the agitator clutch cannot be closed. Now as the water level in the tub builds up, the increasing weight of the water will downwardly deflect the inner works assembly support and as the water reaches the level 27 the switch 37 will be actuated to its second condition at which the circuit is closed to the contact 47, as illustrated by the dotted line showing in Fig. 4 and the circuit to the valve solenoid is opened. As this occurs the clutch solenoid 42 will, of course, be energized and drive will be transmitted to the agitator. Thus it will be readily understood that the agitator canont be set in operation until the water reaches the desired level, regardless of the time which may be required for this operation, so that variations in the water pressure supply to the machine will no longer be a factor. As here shown the timer motor 48 is shown as connected parallel with the clutch solenoid 42 so that the switch 37 effectively overrides the automatic timing mechanism, but the timer motor will, of course, take over operations after the tub has been properly filled.

This particular circuit is to be regarded as an example only and as stated there are other ways by which the control may be exercised over the operation of the machine within the scope of our invention.

It will be noted in Fig. 2 that corner legs 49 are necessarily shown as a part of the base structure, but these are stationary elements for supporting the splash tub 50 and have no bearing upon the vertical deflection of the inner assembly 11 by the weight of the water in the tub.

In the foregoing example of one practical constructi n for our purpose the Weight is measured at one side of the machine by the vertical deflection of a part of the base structure, but as a further example we illustrate in Fig. an analogous arrangement in which the weight is measured at the center of the assembly. In this case the cross member 28 is firmly secured at the end 32, by welding or other suitable means, in the channel 16 instead of being movable. The support point 12 for the inner works assembly 11 is again within a bearing cup 26 but instead of the yieldable bearing 25 we here employ an expansion coil spring 50 braced between the lower member 24 and the bottom 51 of said cup. A spring so arranged will not only permit gyration of the inner works assembly 11 but will also permit vertical deflection thereof and if properly chosen as to strength, the spring will allow the entire inner assembly to move downwardly only when the water in the tub has risen toward the working level 27. Here again a switch 37 is utilized and the same is secured to the bottom 51 of the cup but in this case the switch may be of a snap-action variety having an actuating plunger 52 extending upwardly into the cup and normally cleared by the lower end of the element 12. Thus as the inner assembly deflects downward and the Water level rises to the working level, element 12 will engage and actuate the plunger 52 to throw the switch 37 so that it may control the further operations of the machine, as previously described.

In Fig. 6 we have illustrated as a further example an assembly including an outside stationary casing and an inner frame and works assembly, indicated generally at 11 Said inner assembly 11 include a tub 53 within which there operates a perforated spin basket or tub 54 and in the form of a box-diagram at 55 there is designated suitable support and actuating means for these tubs 53-54 and for whatever type of washing agitator may be employed. In a machine of this type it is the outer tub 53 which contains the water, and however this assem bly is actually arranged it may be conveniently supported upon a support element, indicated generally at 56, arranged to deflect downwardly under the load of the water in tub 53, so that the resulting movement may be utilized for control of the water supply to the machine. We have here indicated the support member 56 as pivoted at one end at 57 to a part 58 of the outer stationary casing structure and with the inner assembly flexibly supported by coil springs 59. At the opposite, movable end of the support member 56 the switch 37 is arranged and here again the same has a plunger 52 which will engage an adjacent stationary element 69 when the inner works assembly moves downward under load. In this case also We illustrate the application of a spring 33 for biasing the moving end of the-support member 56 in an upright direction in a manner very similar to that illustrated in Fig. 1.

It is understood that suitable modifications may be made in the structure as disclosed, provided such modifications come within the spirit and scope of the appended claims. Having now therefore fully illustrated and described our invention, what we claim to be new and desire to protect by Letters Patent is:

1. In an automatic washing machine, the combination comprising an outside stationary frame, an inside assembly including a rotary tub for containing clothes and water and an agitator in the tub, an electrically controlled water valve for filling the tub with water to a working level, an electric motor for operating the tub and agitator, an automatic control circuit for sequentially operating the valve, tub and agitator, and including a valve solenoid for controlling the valve and an agitator solenoid for controlling the agitator, a base structure forming part of the outside frame and having means yieldably supporting the weight of the inside assembly, and a switch operatively arranged for actuation by downward movement of the said yieldable support means and connected in circuit to control both of the solenoids.

2. In an automatic washing machine, the combination comprising an outside stationary frame, an inside assembly including a rotary tub for containing clothes and water and an agitator in the tub, an electrically controlled water valve for filling the tub with water to a working level, an electric motor for operating the tub and agitator, an automatic control circuit for sequentially operating the valve, tub and agitator, and including a valve solenoid for controlling the valve and an agitator solenoid for controlling the agitator, a base structure in the outside frame having means supporting the weight of the inside assembly, said outside frame having upper and lower stationary frame parts and the base structure having an end movable upwardly and downwardly with reference to the lower frame part, a spring biasing said end to an upper position, and an electrical switch operatively arranged for actuation from a first position closing a circuit to the valve solenoid to a second position opening that circuit and closing a circuit to the agitator solenoid as the end of the base structure is moved downward by the increasing weight of the inside assembly as the tub fills with water.

3. In an automatic washing machine, the combination comprising an outside stationary frame, an inside assembly including a rotary tub for containing clothes and water and an agitator in the tub, an electrically controlled water valve for filling the tub with water to a working level, an electric motor for operating the tub and agitator, an automatic control circuit for sequentially operating the valve, tub and agitator, and said circuit including a valve controlling solenoid and an agitator controlling solenoid, the outside frame having a base channel with upper and lower flanges, a base structure having :a support for the inside assembly and fixed at at least one point to the channel and having an end movable upwardly and downwardly between the flanges of the channel under variations :in the weight of the inside assembly, a spring operatively arranged to hold said end against the upper flange when the tub is empty but to permit theend to move downward toward the lower flange as the tub fills with water and the increasing weight of the inside assembly overcomes the spring, and a switch operatively arranged for actuation as the end of the base structure moves downward and the water reaches its working level to de-energize the valve control solenoid and energize the agitator control solenoid.

4. In a clothes washing machine having a rotatable spin tub and an agitator therein, means yieldably supporting the tub for downward movement from an empty to a filled position as liquid is supplied to the tub, a source of liquid supply and electrically controlled valve means for controlling the supply of liquid from the source to the tub, power means for rotating the tub and operating the agitator and including a solenoid for connecting said power means to the agitator, a timer for controlling a sequence of operations of the machine, a timer motor for operating the timer, a switch closed as the said supporting means is moved downward and the tub reaches its filled position, an electrical circuit and said circuit including means connecting the switch to close said valve means, to operate the solenoid and set the agitator in operation, and to start the timer motor to control the subsequent program of the machine when the tub reaches its filled position.

References Cited in the file of this patent

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