Single shaft agitate and spin drive for automatic washer

A single shaft agitate and spin drive for an automatic washer is provided in which a lost motion mechanism or clutch in the form of a plurality of stacked discs is mounted on the agitator shaft, a lower end of the mechanism being driven by the agitator shaft and an upper end of the mechanism driving the basket after a sufficient amount of rotation by the agitator has been inputted to the mechanism. The mechanism absorbs enough rotational motion to allow oscillatory motion of the agitator without transmission of that motion to the basket, but if sufficient rotational motion is input to the mechanism, such as during the spin mode, the mechanism transmits the motion to drive the basket. The amount of rotation absorbed is easily changed by changing the number of discs in the stack.

BACKGROUND OF THE INVENTION 
1. Field of the Invention 
The present invention relates to a drive mechanism for an automatic washer 
and more particularly to a device to allow for a delay between the start 
of rotation of a driving member and the start of rotation of the driven 
member in an automatic washer agitator drive. 
2. Description of the Prior Art 
In the drive of an automatic washer, the agitator is driven either in a 
back and forth agitate motion or in a single direction spin motion 
depending on the particular portion of the wash cycle. Various clutching 
mechanisms have been provided in the prior art to provide a transition 
between oscillatory agitation motion and rotating spin motion. 
U.S. Pat. No. 2,609,697 discloses a drive dog 42 depending downwardly from 
the agitator skirt which engages a drive dog 43 on the basket to carry the 
agitator and basket together during a spin mode and during the agitate 
mode it is stated that the downwardly depending dog 42 will push the 
basket dog 43 out of the way during the first oscillation and then will 
not contact it during subsequent oscillation. 
U.S. Pat. No. 3,248,908 uses an inner and outer helical spring type clutch 
30 to permit oscillatory motion of the agitator without causing 
oscillation of the basket, but continued rotation in one direction during 
spin will cause the clutch 32 engage thus spinning the basket with the 
agitator. 
U.S. Pat. No. 4,059,975 uses a pivoting arm 180 to alternatively be engaged 
by opposed cam surfaces on adjacent pulleys which are rotated in opposite 
directions to result in oscillatory motion when the pulleys are rotated in 
a first direction and results in a spinning of the agitator when the 
pulleys are rotated in a second direction. 
It is desirable in washers to provide a means for driving the basket and 
agitator in a spin mode and only the agitator in an agitate mode. All the 
prior art has provided some solutions for providing this function, these 
solutions are somewhat complicated and use involved clutching mechanisms 
and connecting parts. 
Therefore, it would be an improvement in the art if there were provided a 
simple, yet effective means for permitting oscillatory motion of the 
agitator without causing oscillatory motion of the basket, and for causing 
spinning of the basket upon a given rotation of the agitator, without the 
need for a complicated and expensive clutch arrangement. 
SUMMARY OF THE INVENTION 
The present invention provides a rotational delay mechanism for a single 
shaft agitate and spin drive for automatic washers which permits the use 
of a single shaft to drive both the agitator and spin basket in a spin 
mode, but which permits oscillation of the agitator without rotational 
movement of the basket in a wash mode. Further, the present invention 
provides for a simplified clutch arrangement which is a rotational delay 
mechanism with means for easily varying the length of delay so that it can 
be assured that the agitator is free to oscillate through any given 
oscillatory stroke angle, even one of several rotations, without causing 
the spin basket to be driven, yet assuring that the spin basket will be 
driven in a spin direction after the agitator has been rotated beyond the 
preselected stroke angle. 
The delay mechanism is comprised of a plurality of disc members to be 
stacked on the agitator shaft, each disc having opposed axially extending 
tab or lug portions such that the extending portion of one disc will abut 
against an extending portion of a neighboring disc after sufficient 
relative rotation of the two discs. A driver such as a pulley rotated by a 
motor drives a lowermost disc and an uppermost disc drives a spin tube 
attached to the basket. Thus, when stacked on the agitator shaft, each 
disc will be rotated a given number of degrees before its projection 
engages the projection on the next adjoining disc. During agitate, the 
driver rotates in its oscillating motion fewer degrees in one direction 
than is required for the combination of all the discs to rotate 
sufficiently to provide a driving input to the spin tube. The number of 
turns the disc adjacent the driver makes before the disc at the other end 
adjacent the spin tube begins to rotate is the angular delay and is 
determined by the number of discs and the size of the discs. When the 
driver rotates in a single direction, the lost motion device eventually 
locks up, providing a continuous rotational input to the spin tube. 
Two different embodiments of the disc are disclosed as exemplary 
embodiments of the invention. In a first embodiment, the discs comprise a 
generally circular member with a central hole for passage of the agitator 
shaft and have two radially extending tabs, one tab being turned upwardly 
in an angled axial direction and the opposite tab being turned downwardly 
in an angled axial direction. Thus, when the discs are stacked on the 
agitator shaft, an upwardly turned tab will engage with a downwardly 
turned tab of the next adjacent disc to provide the driving connection 
between the discs. In this manner, each disc may provide at least 
approximately 340.degree. of lost motion. If the disc is made of a larger 
diameter, and the tab remaining approximately the same size, then the 
effective angular width of the tab would be reduced such that a larger 
number of degrees of lost motion could be obtained from each disc. 
A second embodiment illustrated in this disclosure comprises a disc with a 
planar lower surface broken only by a downwardly extending tab or lug 
axial projection molded as part of the disc close to the outer perimeter 
of the disc. The top side of the disc includes an upwardly extending rim 
extending around the entire periphery of the disc and an upwardly 
extending tab or lug projection, radially opposite the downwardly 
extending projection, which terminates coplanar with the perimeter wall. A 
central hub portion is also formed which extends upwardly from the disc so 
that an annular channel is formed in the top side throughout approximately 
340.degree. of the circumference of the disc, the remaining 20.degree. 
being filled with the upward projection. When two such discs are stacked, 
the lower projection of the upper disc fits down into the annular channel 
of the lower disc and the discs are free to rotate relative to one another 
until the adjacent upward and downward projections abut. Then the two 
discs are carried together in a given rotational direction. In this 
embodiment there is also preferably provided an elastomeric bumper which 
is held in the topside of the disc and which projects to either side of 
the upwardly directed projection so that the bumper is engaged by the 
downwardly directed projection before that projection engages the upwardly 
extending projection thereby to act as a cushion and to avoid the impact 
of one projection against the other thereby to reduce or eliminate any 
noise associated with such impact. 
As with the first embodiment, the amount of lost motion can be changed by 
changing disc size or number of discs. Thus, there is provided a simple, 
yet effective means for permitting oscillatory motion of the agitator 
without causing oscillatory motion of the basket, and for causing spinning 
of the basket upon a given rotation of the agitator, without the need for 
a complicated and expensive clutch arrangement.

DESCRIPTION OF THE PREFERRED EMBODIMENTS 
In FIG. 1 there is illustrated an automatic washer generally at 10 having 
an outer cabinet 12 to surround and enclose a wash load receptacle and 
drive mechanism. The wash load receptacle is composed of an imperforate 
wash tub 14 and a concentric inner perforate wash basket 16. A vertical 
axis agitator 18 is concentrically located within the wash basket 16 and 
is driven by means of an agitator shaft 20 which extends through the floor 
of the wash basket 16 and wash tub 14 to be driven by an electric motor 22 
through an appropriate power transmission arrangement such as that 
described below. The washer cabinet 12 has a top openable lid 24 and has a 
console 26 at the rear edge of the top of the washer which includes a 
plurality of control dials 28 to permit a user to select a series of 
automatic washing, rinsing and dehydration steps. 
The interior of the washer is shown in greater detail in FIG. 2 where it is 
seen that the agitator 18 is connected to the agitator shaft 20 by 
appropriate fastening means which may include a spline connection 30 and a 
retaining screw 32. The agitator shaft extends downwardly and is secured 
to a driven pulley 34 which is connected by means of a drive belt 36 to a 
drive pulley 38 mounted on a drive shaft 40 of the motor 22. Thus, the 
agitator is driven by the motor 22 through the pulley and drive belt 
transmission arrangement. This type of a drive arrangement has many 
advantages, such as being able to quickly change pulley diameters to cause 
the machine to run at different speeds, for example when switching between 
60 cycle current and 50 cycle current in different countries. 
The wash tub 14 and wash basket 16 are shown as being suspended from the 
suspension rods 42 which are resiliently mounted to a base plate 44 
beneath the wash basket and wash tub. The motor and drive connection are 
all suspended from the base plate 44. 
During a normal wash cycle, the agitator 18 is oscillated about its 
vertical axis such that lower vanes 46 operate as pumping arms to cause a 
toroidal flow of wash liquid downwardly along the agitator body, outwardly 
along the skirt 48 of the agitator and upwardly along the wall of the wash 
basket 16. This toroidal flow increases turnover of the clothes in the 
wash basket thus enhancing washability. 
During the dehydration or liquid extraction stage of the wash cycle, the 
wash basket 16 is spun at high rate of speed to cause a centrifugal 
extraction of the wash liquid through the perforate wall of the basket. 
The wash basket 16 is driven by the motor 22 through the connection of a 
spin tube 50 which connects to the wash basket at a top end and which is 
indirectly connected to the driven pulley 34 at a bottom end by means of a 
delay mechanism shown generally at 52. A first embodiment of the delay 
mechanism is shown in greater detail in FIGS. 3-5 which illustrate a 
plurality of stacked discs 54 carried on the agitator shaft 20. Each 
individual disc comprises a generally circular member having an upstanding 
circumferential wall 56 extending axially from a floor portion 58. A 
central hub portion 60 also projects axially upwardly and terminates at a 
top wall 62 which is coplanar with a top wall 64 of the circumferential 
wall. Thus, an annular channel 66 is formed between the circumferential 
wall 56 and the hub 60. An axially upwardly extending lug or tab 68 is 
positioned in the annular channel 66 which also terminates flush with the 
tops of the circumferential wall and hub. In the top disc, there is 
mounted a connecting element 70 which provides the driving connection 
between the top disc and the spin tube 50. In each of the remaining discs 
there is mounted an elastomeric bumper 72 in a space between the hub 60 
and the upwardly projecting lug or tab 68. The elastomeric bumper 72 
projects beyond the side walls of the lug 68 into the annular channel. 
On the bottom side of each disc there is a downwardly projecting tab or lug 
74 which is spaced slightly inwardly from the circumferential edge of the 
disc so that when two discs are stacked together, the downwardly 
projecting lug of an upper disc will be received in the annular channel of 
the lower disc. The lowermost disc has its downwardly projecting tab 74 
extending into an annular channel between the pulley rim and the pulley 
hub where it is engagable by an upwardly axially extending drive lug 76 
formed on the pulley. Thus, as the pulley rotates, the drive lug 76 will 
engage the downwardly depending lug on the bottom disc causing the bottom 
disc to rotate with the pulley. Upon continued rotation of the pulley and 
drive disc in the same direction of rotation, the bottom disc will rotate 
until the upwardly extending lug 68 of the bottom disc approaches 
engagement with the downwardly extending lug of the next upwardly adjacent 
disc. 
Just prior to engagement of the two opposed lugs, the elastomeric bumper 72 
carried by the bottom disc will engage the downwardly depending lug 74 of 
the next upper disc. This is illustrated in FIG. 4 wherein the downwardly 
extending lug 74 of the next upper disc is shown in full at the 2 o'clock 
position and is shown in dotted lines in engagement with the bumper at the 
10 o'clock position. By providing the resilient bumper, the driving 
engagement between adjacent discs is cushioned at the point of impact to 
reduce or eliminate noise and to reduce shock to the parts. Once the 
bottom two discs are engaged together by the opposing lugs, they both 
rotate with the pulley and in succeeding fashion each of the remaining 
upper discs are picked up and carried in rotation until finally the top 
disc is picked up which causes the spin tube to rotate. 
As can be seen in FIGS. 4 or 5, each lug comprises an angular extent of 
approximately 20.degree., thus providing loss motion of approximately 
340.degree. per disc. This amount of lost motion can be reduced by making 
the disc smaller while keeping the lug approximately the same size, 
therefore the lug comprising a larger relative angular extent, and the 
amount of lost motion per disc can be increased by reducing the size of 
the lug or making the disc larger so that the lug will comprise a 
relatively smaller angular extent. The total lost motion of the system can 
be changed by changing the number of discs which are in the stacked 
arrangement, each new disc adding the per disc angle of lost motion. Thus 
it is seen that several rotations of lost motion are easily obtainable 
through the use of a few discs. 
Therefore, during the agitate portion of the motion, the motor may be 
operated in an oscillatory manner to provide alternating rotation to the 
agitator shaft 20. Since this alternating motion would be held below the 
amount of lost motion attributable to the disc stack, the wash basket 
would not be driven during this phase of the wash cycle. However, when the 
wash cycle moves into the spin phase, the motor would be operated in a 
single direction and, after sufficient number of rotations of the pulley 
34, all of the discs would be picked up and the basket 16 would be rotated 
along with the agitator 18 to provide the centrifugal extraction of the 
wash liquid from the clothes load. 
An alternative embodiment of the lost motion device is illustrated in FIGS. 
6-10 in which a plurality of discs 80 (seen best in FIG. 8) are stacked on 
the agitator shaft 20 to provide the desired lost motion. Each disc 80 is 
comprised of a circular member having a first radial tab or lug 82 which 
is bent or angled axially upwardly and a second, opposed tab or lug 84 
which is bent or angled axially downwardly. The lowermost disc 80 has its 
downwardly extending lug 84 captured in a cut out 86 in the driven pulley 
so that it will rotate with the pulley. As the lower discs are 
successively picked up during rotation of the pulley, the top ring is 
finally also picked up so that the entire stack of discs will rotate. A 
connecting member 88 connects the top disc to the spin tube 50 to provide 
rotation of the spin tube once all of the discs have been picked up. 
As in the first described embodiment of FIGS. 3-5, the angle of lost motion 
per disc with the second embodiment can be changed by changing either the 
size of the lugs or the diameter of the discs and the overall lost motion 
can be changed by increasing or decreasing the number of discs in the 
stack. 
Thus, with both embodiments, there is provided a lost motion mechanism 
which permits a single drive arrangement, that being of the pulley 34 and 
the associated agitator shaft 20 to impart oscillatory motion the agitator 
18 without effecting movement of the wash basket, even if the oscillation 
of the agitator extends through more than a 360.degree. agitation stroke. 
Once the driven pulley 34 is rotated beyond the lost motion angle, then 
the wash basket 16 is automatically picked up and rotated along with the 
agitator without the need for additional or special clutching arrangements 
other than the very simple stacked disc arrangement. 
As is apparent from the foregoing specification, the invention is 
susceptible of being embodied with various alterations and modifications 
which may differ particularly from those that have been described in the 
preceeding specification and description. 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.