FIELD OF THE INVENTION
The present invention relates to a washing machine. More particularly, the present
invention relates to a washing machine having two tub-type
configuration/arrangement including a wash tub for washing clothes and a spin tub
for spin drying of the clothes.
BACKGROUND
In general, a washing machine for home use is a device which can easily remove dirt
and other foreign particles contained in the washing articles/clothes, using water and
detergents. Washing machine is generally categorized in two broad categories namely
automatic and semi-automatic type washing machines. In the automatic type washing
machine, only one tub is used for washing as well as spin drying of clothes. Whereas
in the semi-automatic type washing machine two tubs namely a wash tub and a spin
tub placed adjacent to each other are provided. The wash tub is used for washing of
the clothes and the spin tub is used for spin drying of the clothes. One such
construction of existing semi-automatic washing (100) is shown in Figure 1. This
washing machine (100) is provided with adjacently located wash tub (101) and spin
tub (102). Also illustrated is an instrument panel (103) for operating either the wash
tub or the spin tub.
In use, after washing the clothes in the wash tub, the clothes are required to be
transferred to the spin tub. With this construction of wash tub and spin tub adjacent to
each other, the said transfer of clothes is cumbersome and also it may happen that
while transferring the clothes from the wash tub to the spin tub for spinning purpose,
water may spill on the floor.
Also, the placement of tubs adjacent to each other occupies more space. Sometimes it
may be a problem for the user to place the washing machine at his home due to space
constraint.
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Therefore, it is the need of the art to provide a semi-automatic washing machine
which occupies less space than the washing machine already provided in the art and
solves or at least reduces the problem of spilling of water while transferring clothes
from the wash tub to the spin tub.
OBJECT
An object of the present invention is to provide a semi-automatic washing machine
which has a spin tub mounted inside a wash tub.
SUMMARY OF THE INVENTION
According to an aspect of the invention a washing machine is provided. The washing
machine comprises a housing, an outer tub located within the housing, an inner tub
located within the outer tub, a motor operatively connected to an impeller and the
inner tub through a drive shaft, and the impeller disposed at the base of the outer tub,
said impeller is axially displaceable between an engaged position and a disengaged
position in which the impeller is engaged and disengaged respectively with the inner
tub.
According to another aspect of the invention a washing machine is provided wherein
the impeller is a floating body.
According to yet another aspect of the invention a washing machine is provided
wherein the impeller is axially displaced between the engaged position and the
disengaged position due to filling and drainage of water respectively in the outer tub.
According to still another aspect of the invention a washing machine is provided
wherein in the engaged position, the inner tub engages with the impeller.
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According to one more aspect of the invention a washing machine is provided
wherein in the disengaged position, the inner tub disengages with the impeller.
According to another aspect of the invention a washing machine is provided wherein
the impeller and the inner tub together rotate in clockwise and anticlockwise direction
in tandem during a wash process.
According to yet another aspect of the invention a washing machine is provided
wherein the impeller and the inner tub are provided with rib structure.
According to still another aspect of the invention a washing machine is provided
wherein the inner tub rotates in a single direction during a spin process.
According to still another aspect of the invention a washing machine is provided
wherein the motor is mounted on a bracket through a suspension member.
BREIF DESCRIPTION OF DRAWINGS
Further aspects and advantages of the present invention will be readily understood
from the following detailed description with reference to the accompanying drawings.
Reference numerals have been used to refer to identical or similar functionally similar
elements. The figures together with a detailed description below, are incorporated in
and form part of the specification, and serve to further illustrate the embodiments and
explain various principles and advantages, in accordance with the present invention
wherein:
Fig. 1 illustrates a conventionally known design of semi-automatic washing machine.
Fig. 2 illustrates a washing machine in accordance with one embodiment of the
present invention.
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Fig. 3 illustrates a line diagram of the washing machine in accordance with one
embodiment of the present invention.
Fig. 4a illustrates the engagement mechanism in accordance with one embodiment of
the present invention.
Fig. 4b illustrates the disengagement mechanism in accordance with one embodiment
of the present invention.
DETAILED DESCRIPTION OF THE INVENTION
It is an object of the present invention to provide a washing machine which addresses
the problems identified in the existing washing machines.
Referring now to the drawings, there is shown an illustrative embodiment of the
invention washing machine. It should be understood that the invention is susceptible
to various modifications and alternative forms; specific embodiment thereof has been
shown by way of example in the drawings and will be described in detail below. It
will be appreciated as the description proceeds that the invention may be realized in
different embodiments.
Before describing in detail embodiments it may be observed that the novelty and
inventive step that are in accordance with the present invention reside in the
construction of the washing machine, accordingly, the drawings are showing only
those specific details that are pertinent to understanding the embodiments of the
present invention so as not to obscure the disclosure with details that will be readily
apparent to those of ordinary skill in the art having benefit of the description herein.
The terms “comprises”, “comprising”, or any other variations thereof, are intended to
cover a non-exclusive inclusion, such that a setup, device that comprises a list of
components does not include only those components but may include other
components not expressly listed or inherent to such setup or device. In other words,
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one or more elements in a system or apparatus proceeded by “comprises… a” does
not, without more constraints, preclude the existence of other elements or additional
elements in the system or apparatus.
Fig. 2 illustrates a washing machine (200) in accordance with an embodiment of the
present invention. This washing machine (200) is provided with a spin tub (202)
disposed inside a wash tub (201). Also illustrated is an instrument panel (203) for
operating either the wash tub or the spin tub. The washing machine may be optionally
provided with a transparent window so that the user can watch the wash and spin
process in progress. The term wash process herein refers to operation of an impeller
or a pulsator. An impeller or pulsator in a wash tub is moved or operated back and
forth by a mechanical force so as to cause turbulence in water in the wash tub.
Further, as the spin tub is disposed inside the wash tub, it is easier to transfer clothes
from the wash tub to the spin tub thereby avoiding/minimizing any spillage of water
on the floor.
Fig. 3 illustrates the washing machine (300) in accordance with an embodiment of the
present invention. Fig. 3 clearly illustrates various aspects of the construction of the
washing machine. An inner tub or spin tub (302) is located in the middle of outer tub
or wash tub (301). The wash tub (301) and the spin tub (302) are driven by single
driving motor (303). The driving motor is mounted underneath the wash tub (301) in
a base area (304). The spin tub (302) is supported on an upper end of a shaft (305)
which drives or rotates the spin tub (302) and originates from the base area (304). The
shaft gets its power from the driving motor (303) provided in the base area (304). The
drive motor (303) is mounted rigidly on the base of the base area (304) of the
washing machine (300). More particularly, the driving motor (303) is supported by
four suspension members (307) which in turn is mounted on a bracket (306). The spin
tub (302) is provided with a coupling (308) at its base. The coupling (308) couples the
spin tub (302) with an impeller (309) mounted above the inner floor of the wash tub
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(301). The impeller (309) is a floating body which can be detachably engaged from
the spin tub according to operation (spin or wash) as required. In other words, the
impeller (309) is axially displaced between the engaged position and the disengaged
position due to filling and drainage of water respectively in the outer tub (301).
During the wash process, when the water is filled in the wash tub (301), the impeller
(309) is lifted upwards due to buoyant force. This upward movement of the impeller
(309) causes the coupling (308) provided at its top and more particularly between top
of impeller (309) and bottom of the spin tub (302) to engage. After the impeller (309)
is engaged with the spin tub (302), they both become one unit and together provide
the function of the impeller or the pulsator during the wash process. More
particularly, the spin tub (302) and the impeller (309) operate together in a back and
forth motion, thus causing turbulence in the water and thereby assisting in the wash
process. The spin tub (302) and the impeller (309) may be provided with ribs on the
surface which is in contact with water in the wash tub (301). These ribs help in
providing mechanical friction or additional turbulence in the water current thus aiding
in washing of the clothes.
During the spin process, when the water is drained out from the wash tub (301), the
impeller (309) is lowered back to its initial position. This lowering of the impeller
(309) causes the coupling (308) provided between the top of the impeller (309) and
the bottom of the spin tub (302) to disengage, thus disengaging the spin tub (302)
from the impeller (309). Therefore, during the spin process, the spin tub (302) rotates
while the impeller (309) remains stationary.
The driving motor (303) is designed in such a way that during wash process it causes
back and forth motion of the engaged impeller (309) and the spin tub (302) and
during the spin process it causes the spin tub (302) to rotate at high speed in a single
direction.
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Fig. 4a illustrates the engagement mechanism in accordance with an embodiment of
the present invention. The figure shows a drive system and the transfer of the motion
from the driving motor to the impeller. The spin tub is fitted on an upper end of the
drive shaft originating from the drive motor. More particularly, the drive shaft ends in
a base area of the spin tub where the coupling is fitted. The coupling is essentially
made up of two parts, the drive coupling and the driven coupling. The drive coupling
is fitted at the bottom of the spin tub and the driven coupling at the top of the
impeller. During the wash process, when the water is filled in the wash tub, the
impeller is lifted upwards, thus causing the driven coupling and the drive coupling to
engage and therefore engage the impeller with the spin tub. Upon starting the wash
process, the back and forth motion transfers from the drive shaft to the spin tub and
then on to the impeller. More particularly the motion in the wash process transfers
from the drive shaft to the drive coupling and then on to the driven coupling.
Fig. 4b illustrates the disengagement mechanism in accordance with one embodiment
of the present invention. During the spin process, the water is drained out from the
wash tub. This causes the driven coupling to disengage from the drive coupling, thus
disengaging the impeller from the spin tub. Therefore, during the spin process the
motion is transferred from the motor to the drive shaft and then to the drive coupling
or the spin tub. Since the driven coupling is disengaged from the drive coupling the
motion is not transferred to the driven coupling or the impeller and therefore the
impeller remains stationary.
The drive coupling and the driven coupling are specifically designed for this
invention such that the clothes do not get entangled in the same.
While the invention has been described with reference to a preferred embodiment, it
is apparent that variations and modifications will occur without departing the theme
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of the invention. It is therefore contemplated that the present invention covers any and
all modifications, variations or equivalents that fall within the scope of the basic
underlying principles disclosed above and claimed therein.

WE CLAIM:
1. A washing machine, comprising:
a housing (300);
an outer tub (301) located within the housing;
an inner tub (302) located within the outer tub (301);
a motor (303) operatively connected to an impeller (309) and the inner tub
(302) through a drive shaft (305); and
the impeller (309) disposed at the base of the outer tub (301), said impeller is
axially displaceable between an engaged position and a disengaged position in which
the impeller is engaged and disengaged respectively with the inner tub (302).
2. The washing machine as claimed in claim 1, wherein the impeller (309) is a
floating body.
3. The washing machine as claimed in claim 1, wherein the impeller (309) is
axially displaced between the engaged position and the disengaged position due to
filling and drainage of water respectively in the outer tub (301).
4. The washing machine as claimed in claim 1, wherein in the engaged position,
the inner tub (302) engages with the impeller (309).
5. The washing machine as claimed in claim 1, wherein in the disengaged
position, the inner tub (302) disengages with the impeller (309).
6. The washing machine as claimed in claim 1, wherein the impeller (309) and
the inner tub (302) together rotate in clockwise and anticlockwise direction in tandem
during a wash process.
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7. The washing machine as claimed in claim 1, wherein the impeller (309) and
the inner tub (302) are provided with rib structure.
8. The washing machine as claimed in claim 1, wherein the inner tub (302)
rotates in a single direction during a spin process.
9. The washing machine as claimed in claim 1, wherein the motor is mounted on
a bracket (306) through a suspension member (307).