US2661620A - Washing machine and vibration damping means therefor - Google Patents

Description

Patented Dec. 8, 1953 WASHING MACHINE AND VIBRATION DAIVLPING MEAN S THEREFOR James F. Young, Bridgeport, Conn, assignor to General Electric Company, a corporation of New York Application November 20, 1947, Serial No. 787,089

7 Claims. l

The present invention relates to clothes washing machines of the type wherein washing is performed in a casket, the basket afterwards being rotated to centrifugally extract the water from the clothes. Ihe invention is especially well adapted for small portable light-weight machines adapted to be readily lifted manually and placed on a (ire-inboard, for example, when the machine is to be used. However, the invention is not limited thereto necessarily.

More particularly the invention relates to a machine of the above type wherein the basket, the washing means, and the mechanism for actuating the washing means and spinning the basket are built as a unitary structure which is mounted in a tub or casing as a unit.

The object of my invention is to provide an improved construction and arrangement in a machine of this character, and for a consideration of what I believe to be novel and my invention, attention is directed to the following specification and to the claims appended thereto.

In the drawing Fig. 1 is a sectional view of a clothes washing machine embodying my invention, and Figs. 2, 3 and 4 are views showing modifications.

Referring to the drawing i indicates the tub of the washing machine which may be supported on a base 2 provided with feet or casters 3. In the tub is a unitary structure comprising a basket 6 having perforations 5, an agitator 6 for performing the washing operation, and a sealed casing 'i in which is an electric motor and mechanism including suitable gearing operated by the motor for oscillating the agitator to perform the washing operation, the basket being then stationary, and for spinning the basket and the agitator to extract the water from the clothes; also in casing l is a suitable supply of lubricant and means for circulating it to the parts requiring lubrication. The structure of the mechanism in casing l is not illustrated as its specific construction forms no part of the present invention. It may be a structure such as that disclosed and claimed in the application of myself and Carl S. Dayton Ser. No. 787,090 for Drainboard Washer Mechanism, now Patent No. 2,511,681, filed of even date herewith, and as signed to the same assignee as the instant application. The tub is provided with a cover 8 and with handles 9 for use in lifting the machine.

My invention has to do primarily with the arrangement of the unitary structure in the tub and the arrangement for damping vibration caused by nonsymmetrical location of the clothes in the basket 4.

Referring to Fig. 1, the unitary structure is supported in the tub by a base spring H) and three side springs H. Base spring it is positioned between a strap l2 attached to the bot tom 53 of the tub, and the bottom of casing i. In the bottom of the tub is an opening M in which the lower end of casing '5 stands. The space between casing "i and bottom it is sealed by means of a flexible diaphragm l5 which may be formed from rubber, for example. It has one edge connected to bottom !3 at the edge of opening [4 and the other edge attached to cas ing 1. This serves to seal the space between the casing and the opening in bottom I3 against leakage. Side springs H are tension springs and are positioned between lugs it fixed to casing 5 and lugs I'i fixed to casing 1. With this arrangement the unitary structure is yieldingly mounted in tub I. Flexible diaphragm it serves to hold casing i from turning and if desired it may be made stiff enough to support the unitary structure in part or entirely.

In performing a washing operation the clothes to be washed are placed in basket 4 and the tub is filled with washing solution to a point slightly above the top row of openings 5. With this arrangement the basket 4 and the casing l are completely surrounded by washing solution. The agitator is now operated to perform the washing operation. After the washing operation is completed, the level of the washing solution in the tub is lowered to a point somewhat below the bottom of basket 4, it being lowered sufficiently to leave space between the bottom of basket l and such level to hold the washing solu tion to be extracted from the clothes. For conveniently lowering the water level to the desired point, I provide preferably a hose is connected to the tub at IS, the level desired n the tub at the beginning of the spinning operation. Normally hose I8 may be supported in a vertical position on the tub by means of a clip 29. After the washing operation is completed hose is may be lowered and its end placed in a suitablereceptacle permitting the washing solution to flow from the tub down to the level it. The hose It may be then again fastened vertically by the clip 26. After the washing solution level has been thus lowered, the basket is spun to extract centrifugally the water from the clothes.

With the foregoing arrangement it will be seen that casing l and the mechanism therein is completely surrounded by washing solution during the washing operation and is partially surrounded during the spinning operation. By such arrangement the washing solution serves to extract heat irom the mechanism and the lubricant in casin I. This serves the double purpose of cooling the mechanism and lubricant and imparting heat to the washing solution.

If additional clothes are not to be washed, then after the spinning operation is completed the washing solution still in the tub may be drained from the tub by means of a hose 2! similar to hose [8 and connected to the tub at its bottom. On the other hand, if additional clothes are to be washed then the washing solution previously drained out through hose [3 may be returned to the tub, or fresh washing solution added to bring the level in the tub up to the desired point.

During the spin cycle, small dissymmetry in the distribution of the clothes in the basket causes vibration of the unitary structure, especially at the critical frequencies, and in this connection I utilize the washing solution in the bottom of the tub to perform two functions, one to add weight to machine and the other as a liquid for a hydraulic vibration dampening system.

As to the first-mentioned function, I provide sufiicient capacity in the portion of the tub below the basket that when the washing solution stands at the level i9, weight is added to the machine sufficient to give good stability during the spin cycle, so as to prevent excessive tub motion. In a small machine, a volume of water may be used having a weight about equal to the weight of the machine. The volume needed is controlled by the machine structure. It should be an amount which represents good economy between effectiveness and cost of construction.

As to the second-mentioned function, I provide dampening means connected to and carried by easing l positioned in the washing solution and cooperating with the washing solution to effect the absorption of vibrations. In the embodiment shown in Fig. l, a cylinder 22 is attached to casing l by several arms 23. Cylinder 22 is formed from relatively thin metal and is positioned below point 19 with its axis vertical. It is sub-merged in the washing solution. On the upper edge of cylinder 22 is a projecting wiper 24 which may be formed from rubber or other suitable material. Pref erably cylinder 22 is provided with rings of openings 25. The cylinder forms in substance a vane carried by easing l and positioned so as to be below the level of the washing solution during the spin cycle. When vibration occurs the vane moves in the solution functionin as a. dampening member to absorb energy and thus limit the amplitude of the vibration.

In a structure as disclosed and with maximum extraction speeds of the order of one thousand R. P. M., for example, there are encountered two critical speeds due to unbalanced clothes in the basket, a first critical speed which may occur at a speed of the order of one hundred R. P. M., for example, and a second critical speed which may occur at a speed of the order of five hundred R. P. M., for example. At first critical speed the node or imaginary point of pivoting of the unitary structure axis occurs at some distanc below the center of gravity of the structure which center of gravity in the present structure is about at the bottom edge of the basket as indicated in Fig. 1. For example such node may be the point indicated in Fig. 1. At second critical speed, the node shifts up to slightly above the center of gravity and then drops to slightly below it, indicated running node in Fig. 1. Use is made of this shift in positioning the damping cylinder in that it is so located and arranged that its motion s will be large with respect to the water and pushes the water as the basket goes through its first critical speed and slight and in such a direction that the cylinder slices through the water rather than pushes it during the second critical speed and up to running speed.

The openings 25 serve to decrease the dampening effect of the cylinder. They may or may not be used and when used may be of an extent to give the desired dampening effect.

The annular wiper 24 engages the inner surface of tub I whenever vibrations occur having an amplitude of motion greater than a predetermined amount. When this occurs, the wiper produces non-linear stiffness as well as rubbing friction.

In Fig. 2 is shown a modification of my invention wherein the clamping member 38 is in the form or a truncated cone supported on the easing by spaced arms 3!. In this instance an annular wiper 32 corresponding to the wiper 2d of Fig. l is shown as being carried by spaced arms 33. The structure of Fig. 2 functions after the manner of that shown in Fig. l. The Fig. 2 construction may be used to take care of a nodal distribution difierent from that of Fig. 1. It may be used to obtain different degrees of damping for the two critical speeds. The angularity of the damping member determines its action with respect to the water.

In Fig. 3 is shown a construction similar to that shown in Figs. 1 and 2 except that the dampening member instead of being a complete ring comprises several sections 35 (three being indicated in the present instance) carried by arms 36. The structure shown in Fig. 3 may be used where a dampening effect less than that of Figs. 1 and 2 is desired.

In Fig. 4 is shown a modification wherein the dampening means comprises pistons it carried at the ends of arms l fixed to the casing and fitting loosely in cylinders 42 attached to the tub wall. The cylinders may be provided with openings as for inward and outward how of washing solution effected by movement of the pistons. This forms in substance a series of dampening dash pots. In the present instance three are indicated but this is only by way of example. Any suitable number may be used.

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

1. In a washing machine having a tub for containing a washing liquid, a unitary structure within said tub comprising a rotatable shaft, a relatively heavy body on said shaft, journaling means for said shaft, means resiliently supporting said journaling means within said tub, and dampening means carried by and spaced radially outwardly from said journaling means and positioned to present a relatively broad surface to the liquid in the tub upon vibrational movement of said unitary structure transverse to the normal axis of said shaft.

2. In a washing machine having a tub for containing a washing liquid, a unitary structure within said tub comprising a rotatable shaft, a relatively heavy body on said shaft, journaling means for said shaft, means resiliently supporting said journaling means within said tub, a dampening ring carried by and spaced radially outwardly from said journaling means, said ring presenting a relatively broad surface to liquid in the tub during rotation of said shaft for dampening vibration of the unitary structure transversely of the normal axis of said shaft, and resilient guard means carried by the dampening ring and normally spaced from the tub side wall for engagement with said tub only upon vibration of predetermined amplitude.

3. In a washing machine having a tub for containing a washing liquid, a unitary structure within said tub comprising a rotatable shaft, a relatively heavy body on said shaft, journaling means for said shaft, means resiliently support ing said journaling means within said tub, and a plurality of ring segment members carried by said journaling means and positioned to present a relatively broad surface spaced from said journaling means to cooperate with the liquid in the tub to dampen vibration of the unitary structure.

4. In a washing machine having a tub for containing a washing liquid, a unitary structure comprising a rotatable shaft, a receptacle on said shaft for carrying an unbalanced load, journaling means for said shaft, a resilient support for said journaling means carried by said tub, and ring sections carried by and surrounding said journaling means in spaced relation thereto and to the tub side wall which present broad surfaces to liquid in the tub during rotation of said shaft for damping vibrations transverse to the axis of said shaft of the unitary structure.

5. For use in a clothes washing machine having an outer tub for containing a Washing solution, a unitary structure comprising a sealed casing, a rotatable shaft journaled therein and extending upwardly therefrom, a receptacle for an unbalanced load carried by said shaft for rotation therewith, motor drive means for said shaft disposed within said casing, means for resiliently supporting said casing within said tub, ring sections carried by and surrounding said casing in spaced relation thereto and to the tub side wall which present broad surfaces to Washing solution in the tub during rotation of said shaft for damping vibrations of the unitary structure, and flexible Wipers carried by said ring sections adapted to engage the tub side wall when vibrations of predetermined amplitude occur.

6. In a clothes washing machine, a tub for containing a Washing solution, means for emptying said tub, a unitary structure within said tub comprising a rotatable clothes basket spaced upwardly from the tub bottom to form a chamber therewith, a sealed casing, a rotatable shaft journaled in said casing and supporting said basket for rotation with said shaft, a motor and gearing in said casing for driving said shaft, means resiliently supporting said casing within said tub, a dampening ring member carried by said casing and spaced therefrom and positioned to present a relatively broad surface for co-operation with said washing solution, and means including a drain in said tube between the bottom of said basket and the bottom of said casing operable instead of said emptying means upon rotation of said basket to partially exhaust said Washing solution whereby said casing and said dampening ring member are at least partially immersed in said washing solution.

7. In a Washing machine having a tub for containing a washing liquid, a unitary structure comprising a rotatable shaft, a relatively heavy body carried on said shaft, journaling means for said shaft, means for resiliently supporting said journaling means within said tub, and a truncated conical member fixed to said journaling means at a point above the vibrational node at the first critical rotational speed and closely adjacent the vibrational node at the running speed and positioned to present a relatively broad surface to the liquid in the tub during vibrational movement of said unitary structure transverse to the normal axis of said shaft.

JAMES F. YOUNG.

References Cited in the file of this patent UNITED STATES PATENTS Number Name Date 1,743,441 Dunham Jan. 14, 1930 1,905,912 Kirby Apr. 25, 1933 2,220,524 Kapitza Nov. 5, 1940 2,285,436 Hoover June 9, 1942 2,405,404 Clark Aug. 6, 1946 2,432,271 Bariffi Dec. 9, 1947 2,454,980 Sobell Nov. 30, 1948 2,538,246 Holm-Hansen Jan. 16, 1951

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