EP0501747A1

EP0501747A1 - Washing and drying machine

Info

Publication number: EP0501747A1
Application number: EP92301565A
Authority: EP
Inventors: Takeshi Fukuchi; Kenji Natuno; Kiyoshi Suzuki; Hiroshi Ohsugi
Original assignee: Hitachi Ltd
Current assignee: Hitachi Ltd
Priority date: 1991-02-28
Filing date: 1992-02-25
Publication date: 1992-09-02
Also published as: JPH04272792A

Abstract

A washing and drying machine for operating in washing, rinsing, spinning and drying modes respectively has an outer frame (1) within which is supported, via suspension rods (2) and vibration absorbers (3), an inner frame (4). The inner frame (4) has opposed axles (6) which support a circularly cross-sectioned tub assembly (5) comprising an outer tub (12) and an inner tub (11). A motor (30) is connected to the outside of the outer tub and is connected by a crank (31) and lever (34) to a pin (33) secured to the inner frame (4) such that the tub may be rotated from a vertical position during which washing and spinning is effected to an approximately horizontal position at which drying is effected. The machine has a drying unit (50) formed by a fan (53) and a heater (56) fixedly secured to the outer frame (1). Flexible conduits (68, 65) connect the drying unit to inlet and outlet ports, respectively, of the outer tub (12). By such an expedient, the drying unit is isolated from vibration from the tub assembly. In a preferred embodiment, a condenser formed by a water spray nozzle (61) is located at the outlet (60) of the outer tub.

Description

BACKGROUND OF THE INVENTION

1. Field of the Invention

This invention relates to a washing and drying machine of the so-called top-loading type.

2. Description of the Related Art

There are basically two types of washing and drying machines, namely top-loading types and so-called front-loading types. The latter type of machine has a drum that rotates about a horizontal axis and clothes are fed into the machine from a front access port. In a top-loading type machine a tub rotates about a vertically extending axis and clothes are inserted into a top, open part of the tub through a clothes inlet access. With a front-loading type machine, because the drum rotates about a horizontal axis, so the machine can be readily used for a washing cycle, a drying cycle, and thence for a drying cycle. In this latter respect, for clothes to be dried, it is necessary for the clothes to tumble inside the machine, i.e. they are revolved from a lower angular part of rotation of the drum to an upper angular part of rotation of the drum whereupon the clothes drop under gravity to the bottom of the drum. Such tumbling action ensures that the clothes can be fully dried. However, such front-loading drum-type machines tend to suffer from vibrational difficulties.
The difficulty, however, with a top-loading type machine is that, although tub rotation about a vertical axis is satisfactory for washing and spinning cycles, such rotation is unsatisfactory for the drying cycle, since no tumbling action is possible.
However, in a prior invention of the applicants there is disclosed a washing and drying machine for operating in washing, spinning and drying modes respectively which has an outer support means formed by a housing and tub means are located inside said housing via vibration insulating members. The tub means is formed by an outer tub and an inner tub for accepting fabric, the inner tub being rotatably mounted in the outer tub. The inner and outer tub combination is rotatably driven by a motor and in the washing and spinning cycles the inner and outer tubs have a substantially vertical axis of rotation. The housing, preferably, has an upper lid through which clothing may be inserted and the outer tub also has a lid through which clothing may be inserted into the inner tub, the inner tub having a closed bottom end and an open top. Because the tubs rotate about a vertical axis during washing, and especially spinning where high revolutions of approximately 800 - 1,000 r.p.m. are achieved, so vibration, which is normally caused by the weight of clothes and water within the machine is reduced. It will be understood that it is usual to provide a plurality of holes in the side wall of the inner tub through which water may drain into and out of the inner tub.
In the prior art, a drying unit comprising a heater and a blower are fixedly and integrally secured to the top part of the outer tub and a rigid, fixed duct extends from the heater to a, normally bottom part of the outer tub (although it may extend to an upper part of the outer tub) and a further duct extends from an upper portion of the outer tub back to the drying unit so that a hot air circulation path is formed. When the washing and spinning modes are complete a motor drivingly rotates the inner and outer tubs from a substantially vertical rotational axis toward an approximately horizontal axis of rotation to effect drying and so that a tumbling action of clothes within the inner tub may be performed.
The clothes are washed by virtue of motion by a motor driven paddle-type pulsator located in the bottom of the inner tub and the paddle may be of the pulsator type where the paddle oscillates through two or three revolutions in each direction of rotation.
The known top-loading drying machine has the following problems:

1. If, as described above, the drying unit is located on the top of the outer tub, then the drying unit is located on one side of the vertical axis opposite to an approximately diametrically extending hinge of a lid on the tub that permits clothes access to the tubs. Because the drying unit has substantial weight, so this tends to cause imbalance of the inner and outer tubs when the spinning mode is in operation.
2. Because the drying unit is located on the top of the outer tub, an excess amount of space is required within the outer housing to permit the inner and outer tub combination to rotate toward the horizontal position for drying.
The above difficulties are also present when the drying unit is located on a side of the outer tub, as is also known.
3. It is highly desirable to use a positive temperature coefficient thermistor (PTC heater), such as that disclosed in US-A-3927300, since such heaters are very efficient and may be readily controlled having high safety. However, if a PTC heater is used as the heater in the drying unit and connected rigidly to the drum, because of the vibration of the drum during spinning, the PTC heater, which is a fragile unit, tends to break and there is the danger that dangerously large currents may then flow.
4. It is sometimes difficult to control the supply of water to the machine and if the water should overflow and the electrically conductive portion of the PTC heater is wetted, there is the danger of the whole machine becoming electrically live. For this reason it is conventional for a coil-type heater to be used, but the surface temperature of such a coil heater is high, as compared with a PTC heater, which causes smoke generation when thread dusts and wool dusts, etc. come into contact with the coil heater. Such a coil-type heater also tends to have the problem that thermal run-away is not easily detected.

The present invention seeks to provide a washing and drying machine in which the above problems may be substantially mitigated.

SUMMARY OF THE INVENTION

According to this invention there is provided a washing and drying machine for operating in washing, rinsing, spinning and drying modes respectively comprising an outer support means, tub means formed by an outer tub and an inner tub which is rotatably mounted in said outer tub, said tub means being located in the support means, rotation means for rotating the tub means from a substantially vertical position when washing and spinning toward an approximately horizontal position when drying, and hot air generating means for producing hot air to dry material in said inner tub in use, characterized in that the hot air generating means is fixedly mounted to said outer support means, and flexible conduit means are provided between said hot air generating means and said tub means for introducing hot air into, and extracting hot air from, said tub means.
Preferably, said hot air generating means is located about the predetermined maximum water level, in use, in said tub means when the machine is in a washing mode.
Advantageously, water condenser means are located in the extraction path between said tub means and said heat generating means.
Conveniently, said condenser means comprises water droplet producing means located in said extraction path at an upper part of said outer tub when said machine is in a drying mode, wherein said water droplets assist condensation of air in said extraction path.
Preferably, at least one electric drive means is provided for driving a washing mode pulsator and for driving said inner tub during the drying mode, said at least one motor being positioned on a base of said outer tub, and condensed air is arranged to travel downwardly past the location of said at least one motor so as to cool the same when in a drying mode.
Advantageously said water droplet producing means comprises a nozzle for producing a spray of water droplets.
Preferably, the flexible conduit means includes a flexible outlet conduit provided between said water droplet producing means and said blower, whereby the outlet conduit is constructed so as to prevent water droplets reaching said blower.
Conveniently, the hot air generating means comprises said blower and a heater, whereby said blower is connected to blow air through said heater.
Advantageously, said heater is a positive temperature coefficient thermistor (PTC) heater known per se.
Preferably, said flexible conduit means further includes a flexible inlet conduit connected between an outlet of said heater and an inlet of said outer tub, the inlet of said outer tub being in an end wall remote from said base.
Advantageously, the inlet of said outer tub is adjacent an upper or lower portion of said outer tub when said outer tub is disposed in a drying mode position.
Preferably, a plurality of drainage apertures are provided about the circumferential side wall of said inner tub, the cross-sectional area of said apertures increasing with axial distance from the hot air inlet of said outer tub and/or extending only three quarters the length of the inner tub from the direction of said base.
Advantageously, said pulsator has a plurality of apertures therein for permitting air to pass therethrough.
Preferably, said condenser means is located in a side wall of said outer tub adjacent the base thereof, whereby hot air is capable of passing through the apertures in the pulsator, upwardly along the outer tub base to said condenser means and, thence, via the flexible outlet conduit to said blower.
Conveniently, there is provided an inner supporting means for rotatably supporting the outer tub, said inner supporting means being located by suspension rods depending from an upper part of the outer support means. Advantageously, the inner supporting means is mounted on said suspension rods through the intermediary of vibration absorbing means.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention will now be described, by way of example, with reference to the accompanying drawings in which:-

Figure 1 shows, in schematic form, a cross-sectional side view of a washing and drying machine in accordance with this invention,
Figure 2 shows a perspective view of part of the machine in a washing and spinning mode of operation,
Figure 3 shows a perspective view of the parts shown in Figure 2 in which the machine is in a drying mode of operation,
Figure 4 shows a cross-sectional side view of the machine to explain the drying mode of operation,
Figure 5 shows the inner and outer tub in a drying mode of operation and the water condenser, and
Figure 6 is a detailed cross-sectional diagram of the water condenser.

In the Figures like reference numerals denote like parts.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

The washing and drying machine shown in Figure 1 has an outer support frame 1 or housing formed by panel sheets and, supported from a top part of the frame 1 by suspension rods 2 via the intermediary of vibration absorbing coil springs 3, is an inner supporting frame 4. The inner supporting frame 4 carries within the confines of the frame 4 a tub assembly 5 which is rotatably mounted in the inner support frame 4 by diametrically opposed axles 6. In this respect, the tub assembly has a circular cross-section and is formed by an inner tub 11 and an outer tub 12, the outer tub 12 being connected by the axles 6 to the supporting frame 4.
The inner tub 11 is arranged to be rotatably driven inside the outer tub 12 by a washing and spinning motor 13 or by a drying motor 14, both motors driving the inner tub through the intermediary of a clutch mechanism 15. The motors 13 and 14 may be connected to the clutch mechanism 14 by, for example, toothed belts and the motors and clutch mechanism are mounted externally on a base 120 of the outer tub 12. Thus, the inner tub 11 is located via a bearing (not shown) which also forms a water seal at the base of the outer tub 12. The inner tub has a plurality of drainage apertures 8 provided about the circumferential side wall of the inner tub, the cross-sectional area of the apertures increasing with axial distance from a hot air inlet to the outer tub (to be described hereinafter). Located internally over an opening in the bottom of the inner tub 11 is a pulsator 7 connected to be driven selectively by the washing and spinning motor 13 via clutch mechanism 15. Located in an axially extending direction around the inner circumferential wall of the inner tub are a plurality of equi-circumferentially spaced lifters 9 for lifting clothes when the machine is in the drying mode of operation, such that the clothes are carried from a lower angular portion of rotation to an upper angular rotational portion and thereupon fall under gravity to the lower angular part of rotation of the inner tub. A ring-shaped fluid balancer 10 is provided at an upper portion of the inner tub, the balancer 10 being partially filled with fluid which tends to counterbalance vibration of the inner tub.
As will be described later with reference to Figure 5, the inner tub 11 has an apertured walled lower end (in the orientation shown in Figure 1) and an open upper end. The outer tub 12 has a closed lower end and an apertured upper end wall 16 on which is located a pivoted lid 17 over the aperture, shown in Figure 2, the lid 17 being disposed over the opening in the inner tub 11 so that clothes may be inserted into the inner tub. Located in the end wall 16 is a water receiving port 28 for receiving water from a water supply 27 receiving water from a water supply valve 26 comprising two independent electromagnetic valves located on a top cover 25 of the outer support frame 1. One of the electromagnetic valves of the water supply valve 26 supplies water into the outer tub 12 via the water receiving port 28. Another of the electromagnetic valves of the water supply valve 26 is a water supply system for a water condenser (shown in Figures 4, 5, 6) in which water carried from valve 26 by a hose 40 is supplied to a nozzle 61 located in a hot air outlet duct 62. The duct 62 is in a hot air outlet 60 located at the confluence of the base and side wall of the outer tub.
A water drain port 180 and a water drain valve 18 are provided on the lowermost part of the outer tub 12 and water is drained from the outer tub 12 via a flexible water drain hose 19 and a relay operated valve 21 through a base 20 of the outer supporting frame to a location external of the machine. The water drain hose 19 has a sufficient length so as not to obstruct rotational motion of the tub assembly 5.
When the tub assembly 5 is in the vertical position (as shown in Figures 1 and 2) for washing, rinsing and spinning, the water drain port 180 is located at the lowermost portion of the outer tub. When the tub assembly 5 is in an approximately horizontal position, the water drain port 180 is also located at a lowermost portion of the outer tub 12, as shown in Figures 3 and 4. Thus, it will be understood that the water drain port 180 is approximately at the confluence of the circular side wall and base of the outer tub.
So as to rotate the tub assembly from the washing, rinsing and spinning position, shown in Figures 1 and 2, to the drying position, shown in Figures 3 and 4, the inner supporting frame 4 has a pin 33 upon which is pivotally mounted a lever 34 having an opposite end thereof connected to a pivot 32 in a crank 31. The crank 31 is connected to a motor 30 fixedly secured on the outer side wall of the outer tub 12. So as to provide improved control, the pivotal output of the motor 30 to the crank 31 may be connected to the axle 6 and the axle 6 may be connected to the pin 33. When the motor 30 is activated and the crank 31 rotates, the pin 33 provided on the inner supporting frame 4 receives a turning torque around the axle 6. Thus, the tub assembly comprising the inner and outer tubs are rotated about axle 6 with respect to the inner supporting frame 4.
Referring to Figures 2 and 3, a drying unit 50 has a blower, including a rotatable fan 53, located in a casing 54 and a PTC heater 56 is located within a casing 57, the fan 53 being configured so as to blow air through a duct 55 over the heater 56. The fan 53 is driven by a motor 51 through a belt 52, the motor 51 being mounted on the outer support frame base 20 through a vibration isolator. The blower has a suction port 63 located in the case 54 and a filter 59, which may be a lint filter, is removably mounted between the suction port 63 and the fan 53, the filter being shown withdrawn in Figure 2. So as to facilitate rotational movement of the tub assembly, the drying unit 50 is fixedly mounted on a side of the outer support frame 1 that is parallel to the axis of rotation, denoted by double arrow-headed lines 600 about axle 6.
A hot air outlet 67 from the heater casing 57 is connected to a hot air inlet 66 provided in the upper end wall 16 by a flexible conduit 68. The hot air outlet 67 of the heater casing 57 and the hot air inlet 66 in the upper end wall 16 are positioned to be at substantially the same height but, preferably, the outlet 67 is not lower than the inlet 66 when the tub assembly is in the vertical position, as shown in Figures 1 and 2 so as to keep the heater safe from accidental water overflow. In this respect, it is desired that the drying unit is located above the maximum water level in the tubs in a washing and rinsing mode.
When the tub assembly 5 is in the vertical position, as shown in Figures 1 and 2, a mid portion of the flexible conduit 68 hangs in a U-shape, thereby preventing vibration being transmitted therealong when the tub assembly is in a spinning mode. When the tub assembly is in an approximately horizontal position, as shown in Figure 3, the flexible conduit 68 is able to follow the motion of the top end 16.
A hot air outlet 60 is located at a lower end of the outer tub (as shown in Figures 1 and 2), i.e. opposite to end wall 16, and the outlet 60 is connected via a duct 62 and a flexible outlet conduit 65 to a universal coupling 64 mounted at the suction port 63 of the blower casing 54. Similarly to the conduit 68, the outlet conduit 65 has a sufficient length to enable the tub assembly 5 to rotate between the positions shown in Figures 1, 2 and the positions shown in Figures 3, 4. It is to be noted that the hot air outlet 60 is positioned to one side of the axis of rotation so that when the tub assembly 5 is rotated to an approximately horizontal position, the outlet port 60 is in an upper portion of the outer tub, above the axle 6.
The hot air outlet duct 62 also performs the role of a water cooling condenser. The water from the water hose 40 is arranged to spray from a nozzle 61 into the hot air outlet duct 62. As shown in Figure 5, the nozzle 61 for introducing condensing water droplets is located in the outlet 62 substantially at the confluence of the side wall and base (when in a vertical position) of the outer tub.
Referring now to Figures 4, 5 and 6, the water spray from the nozzle 61 is condensed by a water guide 80 positioned internally across the outlet 60. The condensed water is arranged to travel along the base 120 supporting the motors 13, 14 and clutch mechanism 15 so as to cool the motors (as shown by broken arrow-headed lines) 181 and passes out of water drain port 180.
The pulsator 7 has a plurality of apertures 70 therein for permitting hot air to pass through the pulsator to the base 120 so that improved condensing is performed. The end of the inner tub to which the motors are connected has a plate 81 formed of a moulded aluminium casting and the plate 81 has radial and circumferential ribs defining apertures 281 through which hot air may pass. A ventilating port 82 is provided in a central portion of the plate 81. The ventilating port 82 has a diameter at least 100mm larger than the internal diameters of the flexible conduits 65 and 68. The end of the ventilating port 82 is reinforced by a ring-shaped flange 83 and an outer side face of the ventilating port 82 is received by the plate 81 to thereby smooth hot air flow and, at the same time, provide compatible reinforcement for the ventilating port 82.
In operation, with the tub assembly in the vertical position, as shown in Figures 1 and 2, the washing, rinsing and spinning modes are performed.
First of all, the lid 17 is open and clothes are put into the inner tub 11. Next the lid 17 is closed and the water supply valve 26 is opened so that water is supplied to the inner tub 11 by the water receiving port 28 from the water supply 27. When the water level in the inner tub 11 reaches a predetermined water level, the water supply is cut off and the pulsator 7 is oscillated by operation of the washing and spinning motor 13 via the clutch mechanism 15. Thus, the modes of washing and rinsing are performed.
The water drain valve 18 is then opened and the washing water in the tub 11 or the rinsing water is drained out of the machine through the water drain hose 19. The clutch mechanism 15 is then automatically adjusted and both the inner tub 11 and pulsator 7 are locked so as to rotate with one another at a high speed of, for example, 800 - 1000 r.p.m., so as to effect spinning. At this time the inner support frame 4 vibrates, but such vibration is damped by the coil springs 3 and, in any event, vibration is not transmitted to the drying unit 50 by virtue of the flexible conduit connection 65, 68 from the outer tub to the drying unit.
After spinning is completed, the motor 30 is actuated and the tub assembly 5 is rotated about axles 6 by the crank 31 and lever 34 so that the tub assembly is inclined to an approximately horizontal position, as shown in Figures 3 and 4.
At this time, the flexible conduit 68 tends to straighten out from its previously U-shape form. Also the end of the flexible conduit 65 connected to the outlet 62 is arcuately moved, but such motion is possible due to flexibility of the conduit 65 and by rotation of the universal coupling 64.
The drying motor 14 and clutch mechanism 15 are actuated so that the inner tub 11 and pulsator 7 rotate in unison at a relatively low speed of 60 - 70 r.p.m. and wet clothes within the inner tub are tumbled by being lifted by lifters 9 and then falling under gravity, the clothes being shown by reference numeral 201 in Figure 4. In Figure 4, although the conduit 68 is shown in broken lines extending outside the confines of the outer frame, it will be understood that this is for ease of representation only and the flexible conduit 68 is located, at all times, within the confines of the outer support 1.
During the drying mode, the fan motor 51 rotates and air is blown over the heater 56, through flexible conduit 68 and enters the outer tub inlet 66. The hot air is heated to a temperature of 100° - 130°C to thus have high temperature and low relative humidity. The hot air, as depicted by arrows 202, travels along the direction of the axis of rotation of the inner tub, through the holes 70 in the pulsator 7 and through the apertures 181 in the receiving plate 81 of the inner tub as well as through the apertures 8 to then pass upwardly along the base 120 and, thence, out of outlet 60 and through the flexible conduit 65 to the universal joint 64 at the suction port 63 of the drying unit to be recycled.
When the wet hot air passes into the outlet 60 it is speedily cooled, condensed and dehumidified by water sprayed from the nozzle 61.
In the above process, the humidity in the clothes is evaporated and the clothes are dried. It has been found that air passing from the outlet 60 has a temperature in the range of 60° - 80°C and a relative humidity in the range 90 - 100%.
The hot air which is passed through the pulsator 7, the ventilating port 82 and the apertures 181 in the inner tub receiving plate 81 flows out smoothly to the hot air outlet 60. Because the hot air outlet 60 is positioned on the upper side of the outer tub 12, no hot air travels against convection movement of the hot air so that smooth circulation of air is ensured. By the constant cycle of air, humidity in the clothes is removed and drying effected.
The provision of the condenser spray nozzle 61 greatly enhances the efficiency of dehumidifying clothes or other articles absorbing moisture inserted into the washing and drying machine. The water sprayed from the nozzle 61 into the duct 62 is at a temperature of about 20°C. Because the hot, damp air entering the outlet 60 is at a temperature of 60° - 80°C, so vapour in the air is discharged as dew upon meeting the cooled water sprayed by the nozzle 61. Furthermore, by virtue of the bend in the outlet conduit 65, so water vapour does not reach the fan 53.
The sprayed cooling water and condensed water from the hot air are received by the condensation water guide 80 and are guided to the base 120. The shape of the water guide 80 also prevents water sprayed from the nozzle 61 and the condensed water in the hot air from re-entering the inner tub 11. As mentioned above, the base 120 is cooled by the condensed water passing therealong so that the base 20 acts as a cooling fin for the motors 13, 14. By virtue of such a cooling system, the inventors believe that the consumption of water can be reduced to 0.2 - 0.5L/min.
When the condensed water reaches the water drain port 180 so it can have the effect of cleaning soap scum from the outer tub. It will also be realised that water outlet for the water condenser is common with the water outlet used for washing and spinning so that no additional outlet is required, thereby providing a simplified structure.
During drying, large quantities of lints are generated which adhere to the inner peripheral face of the outer tub 12, but due to the mode of washing in which the tub assembly 5 is in the vertical position, so such lints can be washed away with the drained water, thereby preventing lints from accumulating in the outer tub 12. Furthermore, the condensation water guide 80 tends to prevent lints from being sucked into the hot air outlet 60 during drying and so also reduces the problem of clogging by lints. The location of the water guide 80 may also guard against small items of clothing which may exit the inner tub in operation from being drawn into the outlet 60.
Additionally, because the hot air outlet 60 and the hot air outlet duct 62 are located in the bottom portion of the outer tub when the tub assembly is in the vertical position, so lints that are collected by condensed water in the drying mode in the outlet duct 62 flow back into the outer tub 12 when the machine is in the washing mode. Thus, the lints from the duct 62 may flow out with drained water so that, again, lint clogging, is reduced.
In the embodiment described above, the apertures 8 in the peripheral wall of the inner tub 8 increase in cross-sectional area with axial distance from the hot air inlet 66 so as to ensure the air introduced into the inner tub passes toward the outlet 60. As well as, or instead of, having apertures 8 which vary in size, the initial one quarter of the inner tub circumferential wall from the hot air inlet 66 may be free of apertures. Thus, if the inner tub has a depth H then the top H/4 portion of the inner tub (as viewed in Figures 1 and 2) may be free of apertures 8. By such an expedient, hot air entering the inner tub is prevented from exiting through the inner tub until it has travelled some axial distance of the tub through the clothing.
The holes 70 in the pulsator 7 may have a diameter of 2mm - 6mm. It is preferable to make the holes as large as possible from the aspect of drying performance, but if the holes are larger than 6mm there is the danger that buttons, hooks, pin, etc. may pass through the holes in the pulsator to cause rotational difficulties thereof.
The present invention has the following advantages:-

1. By remotely positioning the drying unit from the tub assembly so the high reliability and high safety of a PTC heater can be utilized.
2. By remotely positioning the heater above the maximum water level in the tubs, even if, abnormally, water overflows from the tub assembly, so the heater is not wetted, thereby improving safety.
3. Because the drying unit is not mounted on the top of the outer tub, the mass of the tub assembly can be reduced so that the rigidity of the tub assembly can be decreased, thereby making the machine lighter in weight. Furthermore, vibration isolation performance is improved.
4. Because the drying unit is not mounted on the top of the tub assembly, the turning radius of the tub assembly is reduced, thereby rendering the overall size of the machine smaller.
5. Because the drying unit is no longer mounted on the top of the outer tub, the clothes inlet port covered by the top lid can be made larger, thereby making it easier to feed clothes into the machine and remove them from the machine.
6. The provision of a cooled water spray condensing system enhances dehumidifying circulating air which increases overall drying efficiency.
7. Because the condensed water flows along the base 120 of the outer tub, the area of contact with hot air is made larger so that the condensation rate is improved. Furthermore, by cooling the end portion of the outer tub where the motors are connected, so temperature rise in the motors is reduced.
8. By providing apertures on the peripheral wall of the inner tub nearer to the hot air outlet and holes in the agitator, so more hot air is kept in the inner tub with a result that the drying efficiency is improved.

Claims

A washing and drying machine for operating in washing, rinsing, spinning and drying modes respectively comprising an outer support means (1), tub means (5) formed by an outer tub (12) and an inner tub (11) which is rotatably mounted in said outer tub, said tub means (5) being located in the support means (1), rotation means (30 - 34) for rotating the tub means (5) from a substantially vertical position when washing and spinning toward an approximately horizontal position when drying, and hot air generating means (53, 56) for producing hot air to dry material in said inner tub in use, wherein the hot air generating means (53, 56) is fixedly mounted to said outer support means (1), and flexible conduit means (65, 68) are provided between said hot air generating means (53, 56) and said tub means (5) for introducing hot air into, and extracting hot air from, said tub means (5).
A washing and drying machine according to claim 1 wherein said hot air generating means (53, 56) is located about the predetermined maximum water level, in use, in said tub means (5) when the machine is in a washing mode.
A washing and drying machine as claimed in claim 1 or 2 wherein water condenser means (61) are located in the extraction path (65) between said tub means (5) and said heat generating means (53, 56).
A washing and drying machine as claimed in claim 3 wherein said condenser means comprises water droplet producing means (61) located in said extraction path at an upper part of said outer tub when said machine is in a drying mode, wherein said water droplets assist condensation of air in said extraction path.
A washing and drying machine as claimed in claim 4 wherein at least one electric drive means (13 - 15) is provided for driving a washing mode pulsator (7) and for driving said inner tub (11) during the drying mode, said at least one motor being positioned on a base (120) of said outer tub, and condensed air is arranged to travel downwardly past the location of said at least one motor so as to cool the same when in a drying mode.
A washing and drying machine as claimed in claim 4 or 5 wherein said water droplet producing means comprises a nozzle (61) for producing a spray of water droplets.
A washing and drying machine as claimed in claims 5 or 6 wherein the flexible conduit means includes a flexible outlet conduit (65) provided between said water droplet producing means (61) and said blower (53), whereby the outlet conduit (65) is constructed so as to prevent water droplets reaching said blower.
A washing and drying machine as claimed in any preceding claim wherein the hot air generating means comprises said blower (53) and a heater (56), whereby said blower is connected to blow air through said heater.
A washing and drying machine as claimed in claim 8 wherein said heater (56) is a positive temperature coefficient thermistor (PTC) heater known per se.
A washing and drying machine as claimed in claim 7 wherein said flexible conduit means further includes a flexible inlet conduit (68) connected between an outlet of said hot air generating means (53, 56) and an inlet (66) of said outer tub (12), the inlet of said outer tub being in an end wall (16) remote from said base (120).
A washing and drying machine as claimed in claim 10 wherein the inlet (66) of said outer tub (12) is adjacent an upper or lower portion of said outer tub when said outer tub is disposed in a drying mode position.
A washing and drying machine as claimed in any preceding claim wherein a plurality of drainage apertures (8) are provided about the circumferential side wall of said inner tub (11), the cross-sectional area of said apertures increasing with axial distance from the hot air inlet (66) of said outer tub and/or extending only three quarters the length of the inner tub (11) from the direction of a base (120) of said outer tub.
A washing and drying machine as claimed in claim 5 wherein said pulsator (7) has a plurality of apertures (70) therein for permitting air to pass therethrough.
A washing and drying machine as claimed in claim 4 wherein said condenser means (61) is located in a side wall of said outer tub (12) adjacent a base (120) thereof, whereby hot air is capable of passing through the apertures (70) in the pulsator (7), upwardly along the outer tub base (120) to said condenser means and, thence, via the flexible outlet conduit (65) to said blower (53).
A washing and drying machine as claimed in any preceding claim wherein there is provided an inner supporting means (4) for rotatably supporting the outer tub (12), said inner supporting means (4) being located by suspension rods (2) depending from an upper part of the outer support means (1).
A washing and drying machine as claimed in claim 15 wherein the inner supporting means (4) is mounted on said suspension rods (2) through the intermediary of vibration absorbing means (3).