US3063280A - Sealing means - Google Patents

Description

NOV. 13, J BONNER SEALING MEANS Filed April 15, 1960 r IIII INVENTOR.

JOHN I BONNER l HTTORNE) United States Patent 3,063,280 SEALING MEANS John J. Bonner, Philadelphia, Pa., assignor, by mesne assignments, to Philco Corporation, Philadelphia, Pa., a corporation of Delaware Filed Apr. 15, 1960, Ser. No. 22,631 3 Claims. (Cl. 68-23) The present invention relates generally to means for preventing seepage and escape of liquid in structures which during normal use are submerged within a body of liquid. More particularly, the invention has to do with arrangements adapted to establish sealing connections between submersible portions of concentrically disposed members, such as the outer and inner shafts employed as supporting and driving members in automatically controlled cleansing machines of the type wherein a foraminous article-containing basket is enclosed in an imperforate liquid-retaining tub.

One of the main objectives of this invention is to overcome and to solve sealing difficulties and problems which have come about as a result of the generally prevailing practice of adding chemically produced modern detergents or cleansing agents to liquid used in machines for washing or cleaning fabrics.

These difficulties and problems are particularly acute where the seal is between submersible portions of concentric shaft structures in which one shaft member is received within and movable with respect to another shaft member. Accordingly, another object of the invention is to provide a novel and improved sealing arrangement which is especially suited for use with structure of the kind mentioned above, and which insures a leakproof seal between the concentric shaft members of such a structure.

It is generally known that the addition of modern detergents or cleansing agents to a washing or cleaning liquid produces a solution which is subject to seepage and escape. It is also common knowledge that solutions containing modern detergents or cleansing agents chemically react on conventional sealing materials in a manner which reduces and tends'to destroy their ability to resist leakage. For these reasons it has become necessary in most instances to design and employ complicated and expensive seal constructions incorporating special and costly sealing materials. Accordingly it is also an object of this invention to provide a simplified and economical seal arrangement for submersible portions in a structure of the aforementioned variety, the arrangement being adapted to prevent the solution surrounding said portions from coming into intimate contact with the seal proper, thus making it possible to employ ordinary inexpensive sealing materials.

These general objectives as well as other characteristic features and advantages of the invention are attained by cooperatively associating sealing material and structural members in a manner providing a chamber for trapping air below the exposed portion of the sealing material. In this way there is established a protective layer of air which opposes and limits the rise of the liquid in the chamber and which maintains the sealing material dry and unaffected by the washing or cleaning solution. In accordance with a preferred embodiment particularly suited for association with a driven spin-shaft structure, the member defining the air-trapping chamber is so constructed and arranged that any liquid or moisture which might adhere to the wall of the chamber is expelled therefrom in response to spinning of the shaft structure at centrifuging speed.

The nature of the invention, and its objectives and advantages, will be more fully understood from the following detailed description based on the accompanying drawing in which:

FIGURE 1 is an elevational-sectional side view of part of a clothes washing machine of a type adapted for use with the invention; and

FIGURE 2 is an enlarged fragmentary sectional view of a sealing arrangement constructed in accordance with the invention and incorporated in the structure of a machine of the type illustrated in FIGURE 1.

It will be understood that a sealing arrangement embodying the principles of the present invention is not necessarily limited to use in washing machines, and also that the illustrated preferred embodiment of the invention could be employed in a washing machine havingany one of various conventional forms of agitator means. Thus it is merely by way of example that FIGURE 1 of the drawing illustrates an automatic Washing machine with an agitator of the monodirectional wobbling variety.

The illustrated machine is of conventional construction and includes a cabinet 10 which houses a non-rotatable imperforate tub 11 having an outlet drain 12 and enclosing a rotatable foraminous basket 14, the latter being accessible through the cabinet open top 15 which is closed by means of a hinged cover 16. An agitator structure 18 is mounted for movement within the foraminous basket 14 to wash and rinse clothes in liquid which fills the machine to a predetermined level represented at L in FIGURE 1, and which is drained after a clothes-washing operation or a clothes-rinsing operation. The basket 14 is mounted for axial rotation at centrifuging speed to effect spin-drying of the clothes.

The various control and driving means for governing the automatic functions of the machine and for activating the same through its conventional schedule of washing, rinsing, and water draining and extracting operations are Well known in the art and, since such means form no part of this invention, they have not been illustrated and require no description herein. However, for a detailed description of such means as well as of the basic construction and over-all operation of a machine of the general type illustrated in FIGURE 1, reference may be had to United States Patent No. 2,871,689, issued February 3, 1959, to George C. Fields and assigned to Philco Corporation.

In accordance with the present invention there is provided a combination shaft and seal construction in which submersible driven shaft members and elements for mounting said members incorporate a seal arrangement to prevent the leakage of liquid about said members. For these purposes, the bottom 20 of the non-rotatable tub 11 and the bottom 21 of the rotatable basket 14 of the illustrated embodiment are each provided with a central hub 22 and 23 respectively. These hubs, as clearly seen in FIGURE 2, are affixed to the respective bottoms 20 and 21 of the tub and basket by means of suitable securing elements such as screw-bolts 24, and are constructed for association with the shaft arrangement to mount the above-mentioned shaft members.

Asshown, the shaft arrangement includes a rotatable agitator shaft 25 drivingly connected in the usual manner to the agitator structure 18 and disposed within a rotatable spin shaft or tube 26 which is enclosed within an elongated sleeve 27. This sleeve is fixed on and extends upwardly from a supporting frame 28 (FIGURE 1) in a lower part of the cabinet 10 and, in particular accordance with the invention, the upper portion of the sleeve 27 passes through the hub 22 of the tub 11 and is anchored to said hub, for example, by means of rivet pins 29.

The tube 26 encased in the sleeve 27 projects upwardly beyond the upper extremity of said sleeve, and the projected portion of said tube is rigidly connected as by means of a spline 30 to the hub 23 of the basket 14. Thus said basket and tube constitute a spinning unit which can be and preferably is stabilized by means of side thrust bearings, such as the one represented at 33, positioned within said sleeve and installed upon the interior surface thereof to encircle said spin tube.

As clearly seen in FIGURE 2, the seal arrangement of this invention includes an upwardly directed extension 36 of the sleeve 27, a downwardly directed cylindrical flange or skirt 38 depending from the hub 23 of the basket 14 and overlapping the sleeve extension 36, and an annular band of sealing material 40 interposed between the exterior surface of said extension 36 and the interior surface of said flange or skirt 38. As shown, the extension 36 projects for an appreciable distance above the hub 22 and the tub 11, and the band of sealing material 40 is fixed in a retaining ring 41 carried by said skirt in a position where-a ridge 42 of said material frictionally engages and snugly bears upon said extension in close proximity to the upper extremity thereof.

The skirt 38, in turn, projects below the location of the sealing meterial 40 and terminates close to the upper face of the hub 22, so that the clearance 43 betweenthe con-- fronting surface areas of, said hub and of the lower extremities of the: skirt 38 is reduced to a minimum. By

reason ofthe above-described arrangement, the band of sealing material 40 cooperates with said sleeve extension 36 and with said skirt 38 to define. an air-trapping chamher-44. Thus it will be-understood that, when liquid flows into said chamber 44 from the tubv 11 through the clearance 43, air is trapped below the band of sealingmaterial 40, andthat the layer of trapped air prevents liquid from rising in said chamber. Accordingly as represented in FIGURE 2,- the liquid present in the chamber 44 is maintained at level L which is well below the band of sealing material 40 so that the latter remains dry and unaffected by said-liquid.

As shown in FIGUREZ, the inner wall of the flange or skirt38-is slanted to flare outwardly and downwardly toward the terminal'end thereof. In this mannenliquid or condensation which may attach itself to the interior surfaces of=said flange or skirt in the vicinity of the band of sealing material 40 is centrifugally'ejected during spinning of thebasket.

Although a preferred embodimenthas'been shown and described, it will be recognized that the invention is not limited to the specific'structure of this embodiment, but

embraces such changes and variations as come within the scope of the subjoined claims.

Iclaim:

1. In a submersible shaft-and-seal arrangement, the combination of a rotatable shaft, a stationary sleeve encircling said shaft, a skirt member carried by said shaft to rotate therewith and'encirclingsaid sleeve to rotate with respect thereto, said skirtmember defining a chamber within which fluid-is received when said arrangement is submerged, and an annular band of sealing material interposed between the interior'surface of said chamber and the exterior surface of said sleeve and cooperating with said surfaces to trap air in said chamber below said band, said interior surface of said chamber below said band being slanted to flare outwardly and downwardly from said band.

2. A shaft-and-seal arrangement for a liquid-retaining tub having a basket devised to rotate therein, said arrangement comprising a first hub adapted to be affixed to the bottom of said tub, a second hub adapted to be afiixed to the bottom of said basket, said second hub being positioned above and coaxially with respect to said first hub, a rotatable shaft passing through said first hub and affixed to said second hub to rotate the same, a sleeve encircling said shaft and aflixed to said first hub, said sleeve having an extension projecting upwardly from said first hub and terminating adjacent said second hub, a skirt member encircling said sleeve extension and affixed to said second hub, said skirt member projecting downwardly from said second hub and terminating adjacent said first hub, and an annular band of sealing material interposed between the interior surface of said skirt member and the exterior surface of said extension, said band of sealing material and said surfaces cooperating to define an air trapping; chamber below said band, said interior surface of said chamber. below said band being slanted to flare outwardly and downwardly toward the terminating end ofsaid skirt member. p

3. A shaft-and-seal arrangementfor a liquid-retaining tub having a basket devised to rotate therein, said arrangement comprising a rotatable shaft adapted to extend through the bottom of said tub and to be. connected to the bottom of said basket to rotate the same, a stationary sleeve encircling said shaft and having an extension constructed and arranged to project upwardly from said bottom of said tub and to terminate adjacent said bottom of said basket, a skirt member encircling said extension, said skirt member being constructed and arranged to project downwardly from said bottom of said basket and to terminate adjacent said bottom of said tub, and a band of sealing material interposed between the interior surface ofsaid skirt member and'the exterior surface of said extension and cooperating wit-h said surfaces to define an air trapping chamber below said band, said interior surface of said chamber below said band being slanted to flare outwardly and downwardly from said band.

References Cited in the file of this patent UNITED STATES PATENTS 1,699,770 V,oss t Jan. 22, 1929 1,832,352 Behan Nov. 17, 1931 1,853,993 Paquette Apr. 12, 1932 2,067,572 Kirby- Jan. 12, 1937 2,275,680 Myers Mar. 10, 1942 2,605,628 Smith Aug. 5, 1952 2,647,772 Wernert Aug. 4, 1953 2,667,776 Kortepeter et a1 Feb. 2, 1954 2,709,908 Altorfer June 7, 1955v 2,871,689 Fields Feb. 3, 1959

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