US3729960A

US3729960A - Leaf spring suspension for automatic washer

Info

Publication number: US3729960A
Application number: US00212590A
Authority: US
Inventors: F Skinner
Original assignee: Whirlpool Corp
Current assignee: Whirlpool Corp
Priority date: 1971-12-27
Filing date: 1971-12-27
Publication date: 1973-05-01
Anticipated expiration: 1990-05-01

Abstract

A suspension assembly in a clothes washing machine which includes a rotatable clothes receptacle disposed in a tub having a bottom side and a circumferential vertical side and susceptible to off-balance spinning characteristics when unevenly loaded. A plurality of leaf springs are provided, each having a fastened end and a free end, the fastened end being attached to the bottom side of the tub and the free end being disposed adjacent the vertical side of the tub. Dampening means are attached to the free end of the springs and are in frictional contact with the vertical side of the tub. Support means are provided to support the springs, and thereby support the tub resiliently on the springs.

Description

United States Patent [191 Skinner, II

LEAF SPRING SUSPENSION FOR AUTOMATIC WASHER Inventor: Frank R. Skinner, H, St. Joseph,

Mich.

Assignee: Whirlpool Corporation, Benton Harbot, Mich.

Filed: Dec. 27, 1971 Appl. No.: 212,590

US. Cl ..68/23.3, 210/363, 233/1 C Int. Cl. ..D06f 37/24 Field of Search ..68/23.3, 23.1;

[5 6] References Cited UNITED STATES PATENTS FOREIGN PATENTS OR APPLICATIONS 1,468,435 12/1966 France ..68/23.l

[4511 May 1, 1973 1,357,625 3/1964 France ..68/23.1 1,145,131 3/1963 Germany 1,187,269 4/1970 Great Britain ..ss/z3.1 1,545,699 10/1968 France ..68/23.1

Primary Examiner-Leon G. Machlin Attorney-James S. Nettleton et a1.

[ ABSTRACT A suspension assembly in a clothes washing machine which includes a rotatable clothes receptacle disposed in a tub having a bottom side and a circumferential vertical side and susceptible to off-balance spinning characteristics when unevenly loaded. A plurality of leaf springs are provided, each having a fastened end and a free end, the fastened end being attached to the bottom side of the tub and the free end being disposed adjacent the vertical side of the tub. Dampening means are attached to the free end of the springs and are in frictional contact with the vertical side of the tub. Support means are provided to support the springs, and thereby support the tub resiliently on the springs.

9 Claims, 8 Drawing Figures r mmed May 1, 1973 Y 3,129,960

2 Sheets-Sheet 1 Patented May 1, 1973 I 2 Sheets-Sheet 2 Wow/A? LEAF SPRING SUSPENSION FOR AUTOMATIC WASHER BACKGROUND OF THE INVENTION 1. The Field of the Invention This invention relates to a suspension assembly for a clothes washing machine. More particularly, it relates to a leaf spring assembly to provide acceptable offbalance characteristics during spinning for washing machines and the like.

2. The Prior Art The problem of isolating vibrations of the moving parts of a clothes washing machine from the stationary parts is an old one. Many solutions have been proposed for isolating or controlling the vibrations, however, for the most part these solutions have eitherbeen only partially effective or impractical in domestic laundry appliances since they are too expensive to manufacture and too difficult to install in the machine. Also, it frequently occurs that the moving parts of such apparatus or machine must often be allowed only a certain number of degrees of movement and therefore there is a problem of absorbing the vibrations between the moving system or parts and the stationary parts or frame of the machine while maintaining the motion of the moving system within the predetermined limits.

A most common area for this problem of undue and uncontrolled vibration of moving parts in a stationary frame is that encountered in most automatic washing machines of the type presently commercially available for domestic and home use. In such washing machines a clothes basket is provided in which the clothes are washed and rinsed. When, it is desired to remove the liquid from the clothes the basket is spun at a high speed so as to centrifuge the liquid from the clothes. Due to uneven distribution of wet clothes, distribution of weight is not symmetrically distributed about the axis of rotation. The basket or receptacle therefore tends to oscillate and the machine tends to waik on the surface support.

Yet a further item for consideration is that in vertical axis washing machines, i.e., top loading washing machines of the type which have a basket open at its top, it is desirable to have a highly limited amount of vertical freedom both for proper function of the apparatus itself and because of the restrictions on the size inherent in an appliance which is to be used in the space normally available in most homes.

In one form of suspensionassembly heretofore provided, a single cable is used with a networkof pulleys to support the clothes receptacle and the motor assembly from the cabinet. In such assembly there are dampening means provided between thecabinet and the receptacle by leaf springs and a snubber, however, the leaf springs do not provideany support for the receptacle and motor assembly when there is an off-balance load during the spinning operation of the washer.

In another form of suspension for a washing machine, cable and extension springs have-been used where the cable and springs are attached to a platform on which the receptacle is placed. Such suspension assemblies, however, have proved to be faulty in that a spinning motion is not controlled in all directions and the extension springs have a tendency to become loose and ineffective.

SUMMARY OF THE INVENTION The suspension assembly of the present invention can be used in a clothes washing machine including a rotatable clothes receptacle disposed in a tub having a bottom wall and circumferentially extending vertical side walls. A plurality of leaf spring assemblies include a fastened end attached to the bottom wall of the tub and the free end is disposed adjacent the vertical side wall of the receptacle. Dampening means are attached to the free end of each spring and are in frictional contact with the vertical side of the tub. Support means are provided to support the springs, and thereby support the receptacle resiliently on the springs.

The support means may comprise cables connected to the springs and to a support above the level of the springs, or may comprise an underlying frame.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a cut-away view of the clothes receptacle pf a washing machine, illustrating a suspension assembly embodyingthe present invention;

FIG. 2 is an enlarged fragmentary view of one por tion of the suspension assembly illustrated in FIG. 1;

FIG. 3 is a cross-sectional view of the retainer of the suspension assembly taken on line IIIIII of FIG. 2;

FIG. 4 is a view of the attachment of the leaf spring and support cable of the suspension assembly taken on line IV--IV of FIG. 2;

FIG. 5 is a fragmentary illustration of the suspension assembly during the washing portion of the automatic cycle of the washing machine shown in FIG. 1;

FIG. '6 is a cut-away view of another embodiment of the present suspension in associationwith the clothes receptacle of the washing machine shown in FIG. 1;

FIG. 7 isan enlarged fragmentary view of one portion of the suspension assmbly illustrated in FIG. 6; and

FIG. 8 is a view taken on line VIII-VIII of FIG. 7, illustrating the means for connecting a leaf spring to a supporting corner strut of the suspension assembly shown in FIGS. 6 and 7.

DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring to FIG. 1, there is shown a washing machine which has a suspension assembly embodying the present invention. The washer generally indicated at 10 comprises a cabinet 12 in which is mounted a tub 14. In the tub a rotatable clothes basket or receptacle 16 is connected to a drive shaft 18 and may be rotatably driven at spinning speeds by a motor 20 through a transmission 22. An agitator A is also shown which may be oscillated during a washing cycle.

The suspensionsystem consists of 'a plurality of circumferentially spaced spring and cable assemblies, for example, four equidistantly spaced assemblies may be utilized. Each assembly has a leaf spring 24 curved into a generally .V" shaped configuration, although such shape could be compared to a U or to a C. The essential characteristic, of course, is that the spring have two angularlydisposed legs as shown in FIG. 2 at 24a and 24b extending in different directions joined by a bight portion 240. One end as at 24a is fastened to the base plate 26 mounted on the bottom side 27 of the tub 14. The free end 24b is disposed opposite the circumferential vertical side 29 of the tub 14. A dampening pad 28 made of a suitable material is attached to the free end 24b of the leaf spring 24 and is positioned in frictional contact with the vertical side wall 29 of the tub 14.

A support cable 30 is connected to the base plate 26 by means of a clasp 32 which overlies the end 24a of the spring 24. A fastener such as a bolt 34 passes through the clasp 32 and the end 24a and engages the base plate 26. A retainer of clip 36 is provided to maintain the cable 30 in an aligned contact position with the spring 24 to provide support for the receptacle 14. The cable is suspended from a support plate 42 which may be formed in cabinet 12 by a clip 38 at a loop 40 in the cable. Thus, the tub 14 is resiliently nested in the legs 24b of the respective springs 24.

In order to provide a more uniform stress in the springs 24, the base plate 26 is struck out to form a lug or protruding section 44 between each spring 24 and the bottom side of the receptacle 14.

The springs 24 are normally deflected by the weight of the tub 14. The motor and the transmission 22 as well as the other related components and the contents of the machine so there is always a tension on the cables 30. Because of the curved shape of the leaf springs 24, if the basket 16 tends to oscillate during the spinning stage of the washing operation, the unbalanced forces will transmit forces through the suspension so that relative movement will occur between the side walls 29 of the tub l4 and the pads 28 carried by the springs 24. The frictional engagement during such relative movement provides the suspension assembly with a variable dampening.

It is contemplated by this invention that the leaf springs 24 have a relatively low spring constant. Thus, the natural frequency of the suspension assembly will be low and the assembly will pass through its critical resonant frequency at a relatively low spin speed of the basket 16. Also, at high spin speeds the force transmitted to the cabinet will be low. Since the downward vertical forces created by the weight of the clothes and the water in the washing receptacle 14 during a washing operation will be greater than the downward vertical forces created during the spinning operation, it will be noted that the retainers 36 are disposed and shaped to provide a stop or abutment surface 36a engageable with an adjoining surface of the base plate 26 as shown in FIG. 5, thereby to act as a means for limiting the movement of the springs 24 so that the springs are bottomed out. In such bottomed out position, the are or curve of the spring 24 is flattened and the springs are extended.

In FIGS. 6, 7 and 8 there is illustrated another embodiment of the present leaf spring suspension assembly wherein the supporting means or supports for the leaf springs 52 constitute a platform support as con trasted with a cable support. As shown in FIG. 6 and illustrated in greater detail in FIG. 7, the supporting means are corner struts formed by brackets 50 connected to each of the leaf springs 52 and extending down to provide platform support on a support surface provided by the bottom wall 49a of the cabinet 49.

The washer 48 and leaf spring assembly are essentially the same as that of the prior embodiment illustrated in FIGS. 1 through 5, where the washer 48 has a cabinet 49 in which there is a tub 54 and a rotatable clothes basket or receptacle 56 mounted on an agitator post and spin tube assembly 68. The clothes basket 56, accordingly, is rotatably driven in the tub 54 by the motor 60 through the transmission 62.

As shown most clearly in FIG. 7, each of the springs 52 has one end 52a connected to the base plate and bottom wall 55 of the tub 54 by means of a bolt 59 extending through the spring 52 and base plate 58 mounted on the bottom wall 55. The base plate 58 has a lug 64 interposed in between each spring 52 and the bottom wall of the tub 54 to provide a more uniform stress in the springs 52.

A dampening pad 66 is provided on the free end 52b of each spring 52 and is positioned in frictional contact with the vertical side wall 57 of the tub.

As shown in FIGS. 7 and 8, the assembly includes resilient sleeve members 72 having

fasteners

69, 69 projecting from the ends thereof. The spring 52 has an opening 73 through which one of the fasteners 69 extends and the bracket 70 of the corner struts 50 has a corresponding opening 74 through which the other fastener 69 extends.

The opening 73 in the spring 52 is disposed to provide a connection between the support means and the spring. The action of the springs 52 and the dampening pads 66 is similar to that of the springs and dampening pads in the prior embodiment, i.e., the suspension system.

Although minor modifications might be suggested by those versed in the art, it should be understood that I wish to embody within the scope of the patent warranted hereon all such modifications as reasonably and properly come within the scope of my contribution to the art.

The embodiments of the invention in which an exclusive property or privilege is claimed as defined as follows:

1. In a clothes washing machine including a tub having a bottom wall and a circumferentially vertically extending side wall, a support assembly comprising:

a plurality of leaf spring assemblies, each of said spring assemblies having a leaf spring formed with one end fastened to said bottom wall of said tub and a free end disposed adjacent to said vertically extending side wall of said tub;

dampening means attached to said free end of said springs in frictional contact with said vertically ex-' tending side wall of said tub;

and support means connected to said springs for supporting said tub resiliently on said springs.

2. In a clothes washing machine according to claim 1,

a base plate mounted on the bottom wall of said tub, said base plate having a lug projecting therefrom interposed between each of the springs and the bottom side of said receptacle to provide a more uniform stress in the springs.

3. In a clothes washing machine according to claim 1, wherein said support means comprise cables connected to the' receptacle and maintained in contact with said springs to support said receptacle.

4. In a clothes washing machine according to claim 1, wherein said support means comprise brackets connected to each of said springs and project downwardly to a support surface.

5. In a suspension structure for the tub of a vertical to the tub, axis washing machine, a plurality of spring assemblies thereby to resiliently suspend the tub. each comprising a spring member formed of a leaf 7. Inasuspension structure as defined in claim 6, member curved into a generally V" shaped configuraa clip member clamping said cable member and said tion and having first and second legs disposed to pro- 5 pring member in ss ly t n n th and ject in angular relation to one another from an interid clip memb ha ing an abutment surface enmediate bight portion, gageable as a stop with the lower wall of tub.

said first leg underlying the tub, fastener means con- 8- n a p n i n structure as defined in claim necting said first leg in firm assembly with said tub, Said pp means p g; said second leg disposed adjacent the vertical side 10 a Platform pp means Including a bracket for wall of the tub and adapted to frictionally engage each corresponding Spring member having a P the adjoining w ll surf f th b, tion connected to said spring and having a portion and support means engaging said spring member Projecting downwardly for engagement with 3 P- between said bight portion and said first leg, P QQ thereby to resiliently support the tub. thereby to p y Support the 6. In a suspension structure as defined in claim 5, In P struciture as defined said support means comprising a hanging support for a l'eslllem '3" having Stud fasteners proJectmg each corresponding spring member, from pp f ends, said hanging support comprising a flexible cable one end g Connected to l p g and the m b h i one d connected to a point of other end being connected to said bracket, support above h le l fth Spring, thereby to resiliently interconnect the spring and the said cable member being trained over the spring bracketmember and fastened together with said first leg

Claims

1. In a clothes washing machine including a tub having a bottom wall and a circumferentially vertically extending side wall, a support assembly comprising: a plurality of leaf spring assemblies, each of said spring assemblies having a leaf spring formed with one end fastened to said bottom wall of said tub and a free end disposed adjacent to said vertically extending side wall of said tub; dampening means attached to said free end of said springs in frictional contact with said vertically extending side wall of said tub; and support means connected to said springs for supporting said tub resiliently on said springs.

2. In a clothes washing machine according to claim 1, a base plate mounted on the bottom wall of said tub, said base plate having a lug projecting therefrom interposed between each of the springs and the bottom side of said receptacle to provide a more uniform stress in the springs.

3. In a clothes washing machine according to claim 1, wherein said support means comprise cables connected to the receptacle and maintained in contact with said springs to support said receptacle.

5. In a suspension structure for the tub of a vertical axis washing machine, a plurality of spring assemblies each comprising a spring member formed of a leaf member curved into a generally ''''V'''' shaped configuration and having first and second legs disposed to project in angular relation to one another from an intermediate bight portion, said first leg underlying the tub, fastener means connecting said first leg in firm assembly with said tub, said second leg disposed adjacent the vertical side wall of the tub and adapted to frictionally engage the adjoining wall surface of the tub, and support means engaging said spring member between said bight portion and said first leg, thereby to resiliently support the tub.

6. In a suspension structure as defined in claim 5, said support means comprising a hanging support for each corresponding spring member, said hanging support comprising a flexible cable member having one end connected to a point of support above the level of the spring, said cable member being trained over the spring member and fastened together with said first leg to the tub, thereby to resiliently suspend the tub.

7. In a suspension structure as defined in claim 6, a clip member clamping said cable member and said spring member in assembly with one another and said clip member having an abutment surface engageable as a stop with the lower wall of tub.

8. In a suspension structure as defined in claim 5, said support means comprising: a platform support means including a bracket for each corresponding spring member having a portiOn connected to said spring and having a portion projecting downwardly for engagement with a support surface, thereby to resiliently support the tub.

9. In a suspension structure as defined in claim 8, a resilient sleeve having stud fasteners projecting from opposite ends, one end being connected to said spring and the other end being connected to said bracket, thereby to resiliently interconnect the spring and the bracket.