Note: Descriptions are shown in the official language in which they were submitted.
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Title: COMBINED LAUNDRY WASHING AND DRYING MACHINE
FIELD OF THE INVENTION
This invention relates to appliances for washing and
drying and more particularly relates to a combined laundry washing and
drying machine.
BACKGROUND OF THE INVENTION
Conventionally, domestic laundry washing and drying
machines have been separate units. The user first places laundry in a
washing machine, in which the laundry is washed, rinsed and then spun to
remove most of the water. Once it has been washed etc., the wet laundry is
then transferred to a laundry drying machine. This is inconvenient in
many respects. Firstly, two separate machines have to be provided, both of
which are relatively bulky. The cost of two machines is quite high and one
can note that many of the basic control elements, e.g. the cabinet, motor,
clutches, tub and control electronics are duplicated. While having two
machines can theoretically enable a higher throughput, as both machines
can be run simultaneously, this is difficult to achieve in practice and
requires close monitoring of the machines to ensure prompt removal of the
laundry or transfer, when each machine finishes its cycle. Practically, for
most domestic use, the throughput available with a single combined
machine would be sufficient.
A review of the prior art shows that numerous attempts
have been made in the past to provide a combined washer and dryer, but to
applicant's knowledge all of these have been unsuccessful. While some
designer's have appreciated that it is desirable to provide a tub or basket
having an axis which can be tilted between a vertical position for washing
and a horizontal position for drying, they have generally failed to recognize
that the requirements for this drum or basket are quite different for the two
actions of washing and drying. Thus, in conventional, separate washing
and drying machines, the basket for washing is of relatively small diameter
and includes a central agitator that oscillates about a vertical axis, to wash
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the laundry in the machine. For drying, a drum having a relatively large
diameter rotates about a horizontal axis, to create a tumbling action to
promote a flow of heated air through the laundry, to dry the laundry. A
drum for drying typically is totally unobstructed in the middle and includes
a small number of baffles around the periphery to engage the laundry and
cause the tumbling action. Thus, a tub configured for providing a washing
action is not suitable, even if mounted for rotation about a horizontal axis
for drying the laundry. Similarly, a tub or drum configured for a drying
action, is wholly unsuited for providing the agitation for washing laundry,
whatever the orientation of the drum.
In the foreign patent literature the following references, all
dating from approximately the same period, show early examples of
attempts at providing a dual function machine: German Patent
Specification 853,434; French Patent 1,016,540; and British Published
Specification 913,485.
The French and German proposals both appear to teach a
proposal in which a drum or the like can be tilted between two different
positions, with its axis either horizontal or vertical to provide the two
different functions of washing and drying. A different approach is taken in
the British specification, which provides a cylinder for washing, and
proposes moving the cylinder with the laundry in it from the washing
machine to an extraction machine, without the provision of any drying
step.
An early proposal in the U.S. art is U.S. Patent 2,782,622.
Here, the drum is only tilted through a small angle, and again a single
drum of fixed configuration is intended to provide both the washing and
drying actions.
A so-called washing, dehydrating and drying machine is
disclosed in U.S. Patent 5,058,401. The apparatus here is extremely
complicated, and somewhat unusually, provides a spherical container for
the laundry, comprising two hemispherical members molded from resin.
The patent teaches three separate steps, namely: washing with rotation
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about a horizontal axis; spinning about a vertical axis; and drying by
rotation about the horizontal axis. U.S. Patent 5,074,131 describes a
combined washer and dryer that rotates a tub to approximately 75% for the
vertical to initiate the drying mode. This invention utilizes a so-called
pulsator to wash the laundry. A somewhat similar proposal can be found
in U.S. Patent 5,111,673 which also utilizes a pulsator. In both of these
proposals, the pulsator could be characterized as truncated agitators from
conventional washing machines which are intended to provide sufficient
agitation, while leaving the drum or basket largely unobstructed, so that a
tumbling action for drying can be provided. It is believed that such a
compromise will impair both the washing and drying actions. Thus, the
agitator will probably be insufficient to provide a good washing action,
while at the same time it will still be present to interfere with the tumbling
action for drying.
Accordingly, what the present inventor has realized is that,
in order to provide a combined washing and drying machine, it is necessary
to provide some mechanism within the tub or basket, which will enable an
efficient washing action to be provided, while at the same time leaving the
basket unobstructed for tumbling action during drying. The introduction of
a perforated washing plate meets these requirements. By forcing water
through the laundry the plate provides a more effective cleaning action
than the agitators or pulsators in the prior art. Moreover, the present
inventor has realized that it is also desirable to be able to adjust the
effective
size of the basket, to accommodate different size loads. This becomes
particulary important where the basket is large enough, i.e. has a relatively
large diameter in volume, so as to be suitable for drying.
SUMMARY OF THE INVENTION
In accordance with the present invention, there is
provided a machine for washing and drying laundry, the machine
comprising a cabinet, a pivotally mounted subassembly within the cabinet
which moves between a washing and a drying position, an activation
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apparatus for pivoting the subassembly between the washing and drying
positions, a tub within the subassembly, a perforated basket within the tub, a
washer plate within the perforated basket, an apparatus for moving the
washer plate within the basket and an apparatus within the cabinet or
subassembly for drying the laundry. The apparatus for moving the washer
plate within the basket can comprise a continuously helically grooved drive
screw, a pin engaging the helically grooved screw, an apparatus for rotating
the washer drive pin so that it follows the path of the continuous helical
groove in the drive screw and a washer shaft connecting the washer plate to
the drive screw so that rotation of the washer drive pin causes the washer
plate to reciprocate within the basket.
BRIEF DESCRIPTION OF THE DRAWINGS
For a better understanding of the present invention, and to
show more clearly how it may be carried into effect, reference will now be
made, by way of example, to the accompanying drawings which show a
preferred embodiment of the present invention and in which:
Figure 1 is a perspective view of the apparatus of the
present invention showing it in the laundry washing configuration;
Figure 2 is a perspective view of the apparatus of the
present invention showing it in the laundry drying configuration;
Figure 3 is a perspective view of the apparatus similar to
Figure 1, and showing internal details;
Figure 4 is a perspective view of the apparatus similar to
Figure 2, and showing internal details;
Figure 5 is a sectional view of a the present invention
along line 5-5 of Figure 3, showing it in the laundry washing configuration;
Figure 6 is a partial sectional view of a washer drive screw
and associated components;
Figure 7 is a sectional view of the present invention along
line 7-7 of Figure 4, showing it in the laundry drying configuration;
Figure 8 is a perspective view of the apparatus of the
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present invention illustrating the configuration of a water baffle; and
Figure 9 is a top view of the washer plate.
DETAILED DESCRIPTION OF THE INVENTION
Referring first to Figures 1 and 3, both of a perspective
view of the preferred embodiment of the apparatus of the present
invention, which provides a combined washer and dryer, shown in the
laundry washing configuration is generally indicated by the numeral 10.
The principal components of the apparatus consist of a pivotally mounted
subassembly 12, a motor 14 for pivoting the subassembly 12, a main drive
motor 16, a perforated washer plate 18, a washer plate drive screw 20, a
perforated basket 22 and a tub 24.
As shown in Figures 1 and 2, the subassembly 12 is
typically mounted within a cabinet 26 about an axis 28. The cabinet 26 can
be largely conventional and can be for example, formed from sheet steel in
known manner with the dimensions of a conventional washing machine.
The motor 14 is mounted in the base of the cabinet 26, and outside of the
subassembly 12. A pivot arm 30 is attached to the subassembly 12 and
extends perpendicularly from the axis 28. A rotation screw 32 is attached at
one end to the motor 14, and at the other end engages a threaded collar or
nut, attached to a free end of the arm 30. Hence, actuation of the motor 14
causes rotation of the rotation screw 32 which in turn drives the collar and
free end under the pivot arm 30 towards or away from the motor 14. It will
be appreciated that the motor 14 will also be mounted for a small amount of
pivotal movement about an axis parallel to the axis 28, to accommodate
motion of the pivot arm 30, and the threaded collar or nut (not shown)
would be similarly pivotally mounted to the end of the pivot arm 30.
The subassembly 12, as shown in Figure 1, has a top or
access surface 34, a front surface 36, a bottom surface 38 and a rear surface
40.
In the washing position of Figure 1, the front surface 36 is at the front and
the top surface 34 is at the top of the apparatus. To pivot to the drying
position shown in Figure 2, the bottom surface 38 and rear surface 40 must
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be such as to clear fixed components within the cabinet 26. In the drying
position of Figure 2, the top surface 34 is then to the front of the
apparatus,
and the rear surface 40 is then brought to the top of the apparatus as a
whole.
Referring now to Figure 4 a perspective view of the
preferred embodiment of the apparatus is shown in the laundry drying
configuration. An electric heater 42 is mounted to an interior wall of the
subassembly 12. Located diagonally opposite the electric heater 42 and
within the subassembly 12 are the dryer exhaust tube 44 and the dryer fan
46. A dryer exhaust outlet 48 is mounted within the cabinet 26 and provides
an exit for the exhaust air. The dryer exhaust outlet 48 becomes aligned
with outlet from the fan 46, when the subassembly 12 is in the drying
position of Figures 2 and 4. If required a mechanism can be provided to
retract the outlet 48 when pivoting the subassembly 12 and/or when the
subassembly 12 is in the washing position, to prevent interference with the
subassembly 12.
Referring now to Figure 5, Figure 5 is a sectional view of
the preferred embodiment of the present invention in the laundry washing
configuration. The tub 24 contains the perforated basket 22, and they are
both cylindrical in shape. A washer plate shaft 50 extends through the
central region of the tub 24 and the perforated basket 22. The perforated
washer plate 18 is adjustably attached to the washer plate shaft 50 by means
of a washer plate adjustment collar 52, so that the washer plate can be
secured at different positions along the washer plate shaft 50. Mated to one
end of the washer plate shaft 50 is the washer plate drive screw 20.
The basket 22 is rotatably mounted within the tub 24. At
the lower end of the basket 22, as shown in Figure 5, a shaft sleeve 60
extends from the basket 22 through the wall of the tub 24, with a suitable
bearing and seal being provided between them. The shaft sleeve 60 has
mounted on its lower end a relatively large dryer drive pulley 62 and a
smaller spin dry drive pulley 64. The washer plate shaft 50 extends
downwardly through the shaft sleeve 60, and again a suitable bearing and
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seal arrangement would be provided.
Referring now to Figure 6, Figure 6 is a partial view of the
washer drive screw 20 and associated components. The washer plate drive
screw 20 extends from the top surface 34 and is enclosed by a screw cover 54.
Enclosing the washer plate drive screw 20 is a washer drive pulley 66, with
the drive screw 20 free to slide axially and rotatable within the drive pulley
66. A washer drive screw bearing 56 is provided between the drive pulley 66
and a washer drive screw retainer 58. The drive screw retainer 58 serves to
mount the pulley 66 in the top surface 34. A washer drive pin 68 is carried
by the pulley 66 and engages a continuous helical groove 70 in the drive
screw 20. The arrangement is such that the pin 68 continuously travels up
and down the drive screw 20. As the pin 68 is carried by the pulley 66, the
drive screw 20, shaft 50 and attached perforated washer plate 18 are forced to
oscillate up and down as viewed in Figures 5 and 6.
As shown in Figures 5 and 6, a washer drive shaft 72
extends from one end of the main drive motor 16. Mounted on washer
drive shaft 72 is a washer drive screw clutch 74. The washer drive screw
clutch 74 controls drive to a first washer drive pulley, which in turn is
connected by a washer drive screw belt 76 to the washer drive pulley 66, as a
second washer drive pulley, for the washer drive screw 20. Extending from
the end of the main drive motor 16 opposite the washer drive shaft 72 is a
second drive shaft 78. Attached to drive shaft 78 are a dryer clutch 80, a
spin
dry clutch 82, a water pump clutch 84, and a dryer fan clutch 86; each of
these clutches controls a drive connection to a respective first drive pulley,
similarly to the drive screw clutch 74. The pulley for the dryer clutch 80 is
connected to the dryer drive pulley 62 by dryer drive belt 88. The pulley for
the spin dry clutch 82 is connected to the spin dry drive pulley 64 by spin
dry
drive belt 90, and the pulley for the water pump clutch 84 is connected to a
water pump drive pulley 92 by water pump drive belt 94. The pulley for
the dryer fan clutch 86 is connected to a dryer fan pulley 96 by dryer fan
drive belt 98.
As also shown in Figure 5, two water supply hoses 100, one
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for hot water, and the other for cold water, supply water to the tub 24, in
known manner. A water exit or drain 102 connects the tub 24 to a water
pump 104, driven by the water pump drive pulley 92. The water pump 104
is connected on the outflow side to water pump hose 106. The hoses 100,
106 would be sufficiently long and flexible to accommodate pivoting of the
subassembly 12 between the washing and drying positions.
Referring now to Figure 7, a sectional view of the pivotally
mounted subassembly 12 is shown in the laundry drying configuration.
The perforated washer plate 18 contains a hinged, self locking, washer plate
lid 108. In the top surface 34 of pivoting subassembly 12 is a washer/dryer
lid 110. Mounted equally spaced within the circumference of the basket 22
are three dryer baffles 112. As mentioned, the electric heater 42 is mounted
to an interior wall of the pivoting subassembly 12. A drying air inlet 114
allows air to enter cabinet 26. A water baffle 116 allows heated air to enter
the perforated basket 22. A lint filter 118 is mounted at the entrance of the
dryer exhaust tube 44.
Referring now to Figure 8, a perspective view of the
apparatus of the present invention illustrates the function of the water
baffle 116. In the washing position, the water in tub 24 fills water baffle
116.
In drying mode water baffle 116 connects drying air inlet 114 to the interior
of tub 24. The baffle 116 is generally U-shaped and includes a barrier 120,
that is sufficiently high, as viewed in Figure 8, to prevent spillage of water
out through the drying air inlet 114.
Referring now to Figure 9, this shows a top view of the
perforated washer plate 18, which contains a number of perforations 122.
The positioning of the perforations 122 may be irregular as illustrated or
they may form a more regular geometric pattern in the washer plate 18.
Notches 124 in the washer plate 18 accommodate dryer baffles 112. More
particularly, the notches and dryer baffles 112 act like cooperating splines,
to
permit the washer plate 18 to oscillate axially but prevent relative rotation
between them.
The cabinet 26 can include a control panel in known
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manner, and here this includes an electric timer 126 (Figure 1), for
controlling the washing and drying cycles.
In use the combined laundry washing and drying machine
operates as follows: with the apparatus initially in the washing position of
Figures 1, 3 and 5, the user opens the washer/dryer lid 110 exposing the
washer plate lid 108 which is next opened. Soap and laundry to be cleaned
are then deposited in the basket 22. The user then adjusts the height of the
perforated washer plate 18 using the washer plate adjustment collar 52 based
upon the level of laundry in the basket 22. The washer plate lid 108 and the
washer/dryer lid 110 are then closed and the combined washer/dryer 10 is
started by setting the electric timer 126. The electric timer then opens the
water supply valves (not shown) for the water supply hoses 100 until the
tub 24 is filled to the appropriate level, in a known manner water level
sensors can be provided. The electric timer 126 then closes the water supply
valves (not shown) and starts main drove motor 16, with the various drive
clutches disengaged. The washer drive screw clutch 74 is then engaged
which results in the washer drive screw belt 76 rotating the washer drive
pulley 66. The pulley 66 in turn rotates washer drive screw bearing 56. As
the pulley 66 rotates, washer drive pin 68 traces a helical path in the
continuous groove 70 of washer plate drive screw 20, causing the washer
plate shaft 50 to move in a reciprocating motion. The shaft 50 is mounted
in the washer drive shaft sleeve 42, so that it can reciprocate. The washer
plate shaft 50 is prevented from rotating by the dryer baffles 112 which are
retained in notches 124 of the washer plate 18 (Figure 9). As the washer plate
shaft 50 moves downward toward the laundry, the perforated washer plate
18 forces water through the laundry. As the washer plate shaft 50 moves
upward away from the laundry, the perforated washer plate 18 provides a
slight suction action which allows the water to circulate among the laundry.
At the end of the washing cycle as determined by the electric timer 126, the
washer drive screw clutch 74 is disengaged and the main drive motor 16
stops spinning washer drive shaft 72. The water pump clutch 84 is then
engaged which rotates the water pump drive belt 94 which in turn rotates
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the water pump drive pulley 92, and drives the water pump 104 which then
pumps the water out of the tub 24 through the water exit 102 to the water
pump hose 106 which leads to an external drain.
With the pump 104 still running, the spin dry clutch 82 is
then engaged and the spin dry drive belt 90 begins to rotate the spin drive
pulley 64. As the spin dry pulley 64 rotates, it rotates the shaft sleeve 60
which being fixably attached to the basket 22 causes the basket 22 to rotate.
The spin dry pulley 64 is of a diameter such that the basket 22 rotates at a
speed sufficient to effectively remove the water from the laundry by
centrifugal force. The water exits the basket 22 through perforations in the
side of the basket 22 and falls to the base of the tub 24. The water pump 104
then ensures this water is discharged to the water pump hose 106. After the
laundry has been spun for a period of time sufficient to remove a significant
amount of water, the spin dry clutch 82 and the water pump clutch 84 are
disengaged. If desired, this cycle can be repeated with fresh water, to effect
a
rinse action, as is known.
After a time period sufficient to allow the basket 22 to stop
rotating, the user then opens the washer/dryer lid 110, and the washer plate
lid 108 and moves the washer plate 18 (along the washer plate shaft 50) to
the top of the basket 22, using the washer plate adjustment collar 52, thus
creating a large, free area in the basket 22 for the laundry to tumble dry.
The user then sets the electric timer 126 to drying mode
which causes the motor 14 to engage. As the motor 14 rotates the rotation
screw 32, the pivot arm 30 is moved causing the pivotally mounted
subassembly 12 to pivot toward a horizontal or drying position. Once the
subassembly 12 is in the horizontal or drying position, the motor 14 is
turned off. Here, it is noted that it is preferable to provide a mechanism to
lock the subassembly 12 in the washing and drying positions, so that loads
resulting from washing, spinning and drying actions are not transferred
through the pivot arm 30 and rotation screw 32. The main drive motor 16
is then activated and the dryer clutch 80 is engaged. The dryer clutch 80
rotates dryer drive belt 88 which in turn rotates dryer drive pulley 62. As
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dryer drive pulley 62 rotates it causes the basket 22 to rotate, thus tumble
drying the laundry. Simultaneously, the clutch 86 is activated to provide
drive to the dryer fan 46, which draws air through the tub 24 and exhausts it
through the dryer exhaust outlet 48. Within basket 22 are three
conventional dryer baffles 112. Electric heater 42 is activated to heat
incoming ambient air to dry the laundry. Air enters the cabinet 26 through
a drying air inlet 114 due to the suction of dryer fan 46. The air is heated
by
electric heater 42 and enters the tub 24 by way of the water baffle 116. The
dryer fan 46 extracts the moisture laden air from the rotating basket 22
through the lint filter 118 into the dryer exhaust tube 44 and forces it out
the dryer exhaust outlet 48. Once the drying cycle is complete, the electric
heater 42 and dryer fan 46 are shut off. The dryer clutch 80 is then
disengaged and the main drive motor 16 stopped. The motor 14 is then
engaged to retract the rotation screw 32, thus returning the pivotally
mounted subassembly 12 to a vertical position. Once the subassembly 12 is
in a vertical position, the motor 14 is shut off. The user may then remove
the dry laundry by first opening washer/dryer lid 110 and then washer plate
lid 108. Alternatively, the control circuitry can be configured to leave the
subassembly 12 in the drying position, once drying is finished, as many
users may find it more convenient to unload the machine in this position.
Although the preferred embodiment makes use of one
dryer fan 44, improved air flow may be achieved by mounting a dryer fan
near the drying air inlet 114 to push air through the perforated basket 22.
As will be apparent to those skilled in the art, various
modifications and adaptations of the method and system described above
are possible without departing from the present invention, the scope of
which is defined in the appended claims.
