Top loading and front loading washing machines typically have a rotatable drum for holding the clothes to be washed. The drum has a fixed perimeter defined by the sidewall of the drum. After the wash and rinse cycles are complete, the machine normally goes into a spin cycle to extract water from the clothes. During the spin cycle, the drum rotates at relatively high rpms so as to extract water by centrifugal force. An unbalanced condition of the clothes in the drums, causes undesirable vibrations of the washing machine. The larger the diameter of the drum, the more accentuated the vibrations become. Various mechanisms are provided in the prior art-to overcome or reduce the vibrations, including dampers, balance rings, and the like.
Accordingly, a primary objective of the present invention is the provision of a washing machine having a drum which can be expanded for the wash and rinse cycles and contracted for the spin cycle to minimize the effect of unbalanced conditions in the drum.
Another objective of the present invention is the provision of a washing machine having a drum with an adjustable sidewall to reduce the diameter of the drum for the spin cycle.
Still another objective of the present invention is the provision of a washing machine having a rotatable drum with a sidewall comprised of pivotal wall segments to alter the diameter of the drum.
Another objective of the present invention is the provision of a method of washing laundry in a washing machine including the steps of expanding the diameter of the drum for the wash and rinse cycles and contracting the diameter of the drum for the spin cycle.
A further objective of the present invention is the provision of a clothes washing method comprising simultaneously and equally pivoting wall segments of the drum sidewall to reduce the drum diameter for the spin cycle of the machine.
Yet another objective of the present invention is the provision of a washing machine having a contracting drum to minimize vibrations from unbalanced conditions during the spin cycle.
These and other objectives will become apparent from the following description of the invention.
The washing machine of the present invention includes a rotatable drum for holding the clothes or articles to be washed. The drum includes first and second end walls, and a plurality of wall segments connected to the end walls so as to define a continuous sidewall extending 360°. The wall segments are moveable between expanded and contracted positions such that the diameter of the sidewall is variable. The wall segments include first ends pivotally connected to the end walls and second ends which are moveable inwardly and outwardly relative to the axis of rotation of the drum. The inner ends of the wall segments are pivoted inwardly by a rotating shaft and a linkage assembly so as to contract the drum diameter for the spin cycle, thereby minimizing the vibration effects of an unbalanced load condition in the drum.
The laundry washing method of the present invention involves the steps of moving the sidewall segments of the drum to an expanded position for the wash and rinse cycles of the machine, and moving the wall segments to a contracted position for a spin cycle of the machine. Adjacent wall segments are maintained in contact with one another in both the expanded and contracted positions. The wall segments are moved simultaneously and equally during expansion and contraction. Movement of the wall sections is controlled by a linkage assembly and actuated by a rotatable shaft.
A clothes washing machine 10 includes an outer drum 12 and a rotatable inner drum 14. The outer drum 12 is conventional. As shown in
The inner drum 14 has an adjustable diameter which can be expanded and contracted during operation of the washing machine 10. More particularly, the inner drum includes a front end wall 16 and a rear end wall 18. The front end wall 16 has an opening 17 to provide access into the drum 14. The sidewall of the inner drum 14 is defined by a plurality of wall segments or flaps 20A-D, each of which have an outer end 22 and an inner end 24. The outer ends 22 of the segments 20A-D are pivotally connected to the end walls 16, 18, such that the segments 20A-D are pivotal about the pivot points 28A-D. Thus, the sidewall segments 20 are moveable between an expanded position for the wash and rinse cycles of the washing machine 10, as seen in
Adjacent segments 20 engage one another in both the expanded and contracted positions. The inner drum 14 has a substantially cylindrical shape in both the expanded and contracted positions.
Movement of the segments 20 between the expanded and contracted positions is controlled by a linkage assembly, as seen in
The linkage assembly also includes an actuation shaft 38 rotatably mounted in a bearing on the rear wall 18. The shaft 38 has a bar 42 fixed thereto extending opposite directions from the shaft 38. A pair of arms 44 are pivotally connected to the opposite ends of the bar 42 and the second connection points 34A and 34C of the plates 30A, 30C. The arms 44 are shown to be L-shaped in
The shaft 38 is rotated in opposite directions by a reversible motor (not shown). The motor is operatively connected to the controls of the washing machine 10 such that the shaft 38 is rotated in a first direction to move the wall segments 20A-D to the contracted position, via the linkage assembly, just prior to the spin cycle. At the completion of the spin cycle, the motor rotates the shaft 38 in the opposite direction so as to move the wall segments 20A-D to the expanded position. It is understood that the wall segments 20A-D may be moved between the expanded and contracted positions using other means, without departing from the scope of the present invention. For example, the segments 20A-D could each have separate drive motors which would move the wall segments 20A-D between the expanded and contracted positions, either simultaneously or sequentially.
The invention has been shown and described above with the preferred embodiments, and it is understood that many modifications, substitutions, and additions may be made which are within the intended spirit and scope of the invention. From the foregoing, it can be seen that the present invention accomplishes at least all of its stated objectives.