Washing Machine Having Waste Threads Screening Means

Abstract

In a washing and dehydrating machine comprising a vessel having a basket concentrically arranged therein, and a pulsator disposed at the bottom of the basket, the improvement comprises vane means formed at the back side of the pulsator for providing pumping action to produce water flow from a space between the basket and the vessel through the back side of the pulsator into the basket, and screen-like filter means provided below the pulsator and covering perforations formed in the basket so as to remove waste threads separated from clothings during washing.

Description

BACKGROUND OF THE INVENTION

The present invention relates to waste threads screening means for a washing and dehydrating machine in which washing and dehydrating operations are performed in a single vessel. More particularly, the present invention relates to waste threads screening means for a washing and dehydrating machine comprising a water vessel, a basket having perforated peripheral wall means and disposed in said vessel and a pulsator provided at the center portion of the bottom of the basket, whereby said vessel is filled with water and the pulsator is operated for washing and rinsing operation but the vessel is evacuated of water and the basket is rotated in one direction at a high speed for dehydrating operation.

DESCRIPTION OF THE PRIOR ART

Hithertofore, in a washing machine of the type having a pulsator, ravellings has been often produced in clothings during washing operation and deposited on the cleaned clothings causing adverse appearance thereof. For this reason, there has been proposed to provide waste threads screening means for collecting the waste threads during washing or rinsing operation in order to prevent them from depositing on the clothings to be cleaned. A known waste threads screening means includes means for constituting a flow passage from the vessel through conduits and a pump to return to the vessel, and filter means provided in the flow passage for screening waste threads in the flow. In this arrangement, however, it is necessary to provide a pump for producing the circulation of flow and also it is necessary to clean the filter means with suitable intervals to remove the waste threads caught by the filter means. Thus, the arrangement is disadvantageous in that it is inconvenient to use and also it is structurally complicated.

Another known type of waste threads screening means includes an agitator which is provided in the center of the vessel for reciprocating rotational movement, means being provided for forming a flow passage which allows water to flow under the influence of the agitator. A filter means is provided in the flow passage for screening waste threads in the water flow. This arrangement cannot be employed in a washing machine of the type having a pulsator because the pulsator does not have a flow passage therein. Further, this arrangement is also disadvantageous in that it is necessary to remove waste threads caught by the filter means.

Thus, according to conventional arrangements, it has been required to remove filter means for cleaning it and removing waste threads caught by the filter.

SUMMARY OF THE INVENTION

An object of the present invention is to provide waste threads screening means for a washing machine which is convenient to dispose waste threads caught by said means.

Another object of the present invention is to provide waste threads screening means which is simple in construction and in which a circulation of water flow is provided by a water flow produced at the back side of a pulsator in a washing machine and waste threads in the water flow is screened.

A further object of the present invention is to provide waste threads screening means in which waste threads caught by filter means can automatically be disposed of by a water flow produced during water discharging.

Still further object of the present invention is to provide waste threads screening means which occupies less space and is reliable without requiring any maintenance work.

A further object of the present invention is to provide waste threads screening means in which separation of waste threads deposited on the undersurface of filter means by causing the filter to rotate at a high speed with basket of washing machine.

According to the present invention, there is provided a washing and dehydrating machine comprising a water vessel having a water discharge port at the bottom portion thereof and adapted to be filled with water, a basket provided in the water vessel and having a perforated peripheral wall, a pulsator disposed at the center of the bottom of said basket, a pulsator shaft secured to said pulsator, a basket shaft secured to the bottom portion of said basket, means for selectively transmitting power to said pulsator shaft and said basket shaft, radially extending bead means provided on the back side of the pulsator for providing centrifugal pumping action, water passage means connecting the back side of the pulsator with the space between said water vessel and said basket for introducing the water in said space to the back side of the pulsator, and filter means including a screen of fine mesh rotatable with said basket for screening waste threads in the water flowing in said passage.

BRIEF DESCRIPTION OF TH DRAWINGS

FIG. 1 is a longitudinal sectional view of a washing and dehydrating machine embodying the present invention;

FIG. 2 is a longitudinal sectional view showing the detail of waste threads screening means;

FIG. 3 is a bottom view of the flange;

FIG. 4 is a plan view of the filter; and,

FIG. 5 is a sectional view showing the filter fitting.

DESCRIPTION OF THE PREFERRED EMBODIMENT

FIG. 1 shows a washing and dehydrating machine having a pulsator. The machine includes an outer housing 1 made from a steel plate to a box-like form. The housing has corner plates 2 welded at corners of the upper portion thereof for suspending a water vessel 13 in the housing. Although in FIG. 1 only one corner plate 2 is shown, it should be understood that all of the corners of the upper portions of the housing has identical plates 2. The plate 2 has a hole 3 for receiving a suspending rod 5 and a semi-spherical recess 4 for co-operation with a semi-spherical slider 6 secured to the upper end of the rod 5. Each suspending rod 5 extends downwardly through a fitting 10 secured to the peripheral wall of the water vessel 13 and has a spring seat 7 secured at the lower end thereof. A coil spring 8 and a part-spherical slider 9 are disposed between the fitting 10 and the coil spring 8. The fitting 10 has a part-spherical recessed surface 11 for co-operation with the part-spherical surface of the slider 9. The slider 9 has a rubber tube 12 which is fitted to the lower end of the slider 9 and adapted to be put into pressure contact with the outer surface of the coil spring 8. Thus, the vibration of the vessel 13 is absorbed by the coil spring 8 and the frictional sliding movement between the rubber tube 12 and the spring 8. The vessel 13 is of a cylindrical form having a bottom and a side wall. The bottom of the vessel has at its center a hole 14 for passing a basket shaft 17 therethrough as well as a water drain port 15, and the side wall has at its upper portion an overflow port 16. The basket shaft 17 extends upwardly through the bottom of the vessel 13 and is secured at its upper end to the bottom of basket 19 through a flange 18. The basket shaft 17 is of a hollow tublar form as shown in FIG. 2 and, through the hollow interior thereof, a pulsator shaft 20 extends upwardly. The pulsator shaft 20 supports a pulsator 21 in the basket 19 adjacent the bottom thereof. The pulsator 21 is engaged with a recess 22 formed on the bottom of the basket 19 and projecting upwardly from the recess.

The basket 19 has in its peripheral wall a plurality of water separating perforations 23 but is free from perforations at the lower area of the peripheral wall for the reasons explained later. The flange 18 serves to connect the basket shaft 17 to the basket 19 and also is provided with holes for allowing water in the space between the vessel 13 and the basket 19 to the back side of the pulsator 21 as shown in FIG. 2 and means for holding a filter which is simply shown by a block in FIG. 1. At the lower surface of the vessel 13, there are provided a motor 24 and clutch means 25 for transmitting the power from the motor selectively to the basket shaft 17 and the pulsator shaft 20, a belt 28 being stretched between a pulley 26 on the motor and a pulley 27 on the clutch. A water drain hose 30 and an overflow hose 31 are connected respectively to the water drain port 15 and the overflow port 16. Each of the hoses is connected through a cock 32 to an outer hose 33.

FIG. 2 shows details of waste threads screening means which is secured to the basket 19 by means of bolts 37 at a portion below the pulsator 21. The flange 18 has at its center a hose 34 which is formed with a hole 35 for receiving the basket shaft 17 and a key-groove 36 for securing the basket shaft 17 to the flange 18. A plurality of water ports 40 are provided between the boss and threaded holes 38 for the bolts 37. The basket shaft 17 is provided below the portion engaging to the flange 18 with a shoulder portion 41 for supporting the boss 34 through a washer 42. The flange 18 is secured to the basket shaft 17 by means of a nut 44 threadably engaging with the threaaded end 43 of the basket shaft 17. On the lower side of the flange 18, there is provided a plurality of circumferentially spaced nails 45 as shown in FIGS. 3 and 4. A filter 46 is provided below the flange 18 and has an outer diameter d.sub.2 which is larger than the inner diameter d.sub.1 defined by the ends of the nails. Thus, the filter 46 is put into engagement with the nails 45 by resiliently deforming them. The filter 46 comprises an annular nylon screen of 20 to 40 meshes which is reinforced at its inner and outer peripheries 47 and 48, respectively, by resilient plastic members made of such as polypropyrene. The inner diameter of the inner periphery 47 is smaller than the outer diameter of the washer 42.

The basket shaft 17 is supported by a bearing sleeve 50 which is water-tightly mounted on the bottom of the water vessel 13 through a seal member 49. A water seal 51 is provided around the upper portion of the bearing sleeve 50 for preventing water from entering the bearing portion. The bearing sleeve 50 is secured to the bottom of the vessel 13 together with the clutch means 25 by means of bolts 52. The pulsator shaft 20 is supported by a bearing 53 disposed in the basket shaft 17. A pulsator 21 is secured to the pulsator shaft 20 by means of a screw 54.

The pulsator 21 may be of a moulded plastic having blades on its upper surface for producing water flow in the basket. When the pulsator is formed by a plastic moulding technique, it may preferably have radially extending beads on the lower surface for the purpose of providing uniform wall thickness thereof. The beads also provide passages for the water flow from the water ports 40. When the pulsator has a flat lower surface, there must be formed a plurality of radially extending ribs for the purpose of producing forced circulation flow.

In order to assemble the machine, the filter 46 which is previously reinforced at its inner and outer peripheries 47 and 48 by the plastic members is fixed to the flange 18 by putting the outer periphery 48 into engagement with the nails 45. The filter 46 and the flange 18 thus assembled are then engaged with the basket shaft 17. Thus, the inner periphery 47 of the filter is supported by the shoulder 41 of the basket 17 through the washer 42. The flange 18 is provided at its lower surface with small bosses 55 each having a small threaded hole 38 and an annular rib 56 is formed along a circle defined by the bosses. Thus, the filter 46 is supported on the lower surface of the flange with a predetermined distance therefrom by said rib 56. After the flange 18 is put on the basket shaft 17, the nut 44 is placed to secure the flange thereon and thereafter the pulsator 21 is placed on the pulsator shaft 20 and secured thereto by the screw 54.

In operation of the washing machine constructed as described above, clothings to be washed are put into the basket and the water vessel is filled with water and soap. Then, the clutch means is actuated so that the power from the motor 24 is transmitted to the pulsator shaft 20 and thereafter the motor is started. Thus, the pulsator 21 is started to rotate so that the blades on the upper surface thereof produce waterflow and, at the same time, radially outwardly directed water flow is produced in the space between the pulsator and the recess 22 of the basket by the beads on the lower surface of the pulsator. The water flow is produced by the centrifugal pump action of the beads on the lower surface of the pulsator, water being taken into the pump through a water port provided near the center of the pulsator and discharged at the outer periphery thereof.

Thus, when the pulsator 21 is operated, the water around the port 40 is passed through the space between the pulsator 21 and the recess 22 of the basket 19 into the chamber in the basket. At the same time, water in the space between the basket 19 and the vessel 13 flows into the port 40. Thus, a circulation flow is produced as shown in FIG. 1. The screen filter 46 disposed beneath the port 40 effectively catches waste threads in the circulating flow.

It should be understood that the ratio of the waste threads caught by the filter 46 to those produced in the basket may vary in accordance with the amount of water flow passing through the filter 46, the ratio increasing with the increase in the water flow.

However, an increased water flow produces an increased load imparted on the motor. The inventors found that, in a washing machine having a rated capacity of 2.5 to 3.0 Kg, a water flow of 30 ml/min. can provide a practically satisfactory waste thread catching effect without substantially increasing the load on the motor.

Waste threads are mainly produced through rubbing contact of the pulsator with clothings being washed. Since the waste threads are floating in the water stream during washing operation, it is essential to put them in the water flow passing through the filter 46. Further, since the waste threads are often floating near the water surface, it is preferable to take water into the filter 46 from water ports formed in the upper part of the basket. Thus, it is recommendable that the basket has perforations concentrated at the upper part thereof. Further, the perforations in the basket must be of sufficient diameter to allow waste threads to pass therethrough. The inventors have found that the perforations should be as large as possible but are practically satisfactory results can be obtained by those having diameter of 3 to 5 mm.

Conventionally, the pulsator is rotated either in only one direction or in the opposite directions with predetermined time intervals. Therefore, in order that the pulsator provides the same pumping effect in both direction of rotation, it is preferable that the beads or ribs on the lower side of the pulsator extend straightly in radial direction. When the pulsator 21 is rotated, waste threads are gradually accumulated on the filter 46 so that the filter should preferably have an effective area which is as large as possible in order that the flow resistance of the filter is not adversely increased. The flange which has the water port 40 is also formed with an annular rib 56 on the lower side thereof so that a gap d is maintained between the filter 46 and the lower side of the flange 18. With this arrangement, it is possible to provide a sufficient effective area of the filter 46 so that the flow resistance is not increased even when a lot of waste threads are accumulated.

After the washing operation is proceeded for a predetermined time, the motor 24 is stopped and the valve 32 is actuated to drain the water. During the draining operation, the water in the basket 19 is discharged through perforations therein and the space between the vessel 13 and the basket 19, and then through the water draining port 15. A portion of the water in the basket is at that time allowed to flow through the water port 40 and downwardly through the filter to perform reverse washing. After the water level in the basket comes below the area of perforations, all of the water is passed downwardly through the filter. Thus, the waste threads caught by the filter during washing operation is exhausted from the machine together with the drain water.

When the filter is made of a rough metallic wire screen, the waste threads are often entangled around the wires of the screen so that they cannot be removed by the reverse washing. Therefore, the filter must be as fine as possible in order to avoid this disadvantage, however, it should not be so fine that the flow resistance is adversely increased. The inventor has found that a screen of 20 to 40 mesh provides a satisfactory result, and the waste threads can be easily exhausted through reverse washing while the flow resistance can be maintained practically low. The screen may be of metallic material, however, it is preferable to use a nylon screen since the latter is free from corrosion and capable of attaching reinforcing plastic members to the inner and outer peripheries thereof. The nylon screen is also preferable because the waste threads caught thereby can be removed more easily than in another metallic wire screen because the former is always shaken by the water flow during washing operation.

By using a nylon screen of 20 to 40 mesh as the filter 46, it is possible to exhaust a substantial part of the waste threads caught by the filter during washing, however, a small part may still remain on the lower surface of the filter. However, during a succeeding dehydrating opertion, the filter 46 is rotated at a high speed together with the basket 19, so that the remaining waste threads are subjected to a centrifugal force and forced to move radially outwardly along the lower surface of the filter 46. Thus, during the dehydrating operation, the waste threads are dropped to the bottom of the vessel 13. In a washing and dehydrating machine, it is not likely that the work is terminated by the washing and draining operations but the dehydrating operation usually follows to the draining operation. Thus, the waste threads remaining on the filter are not dried thereon because they are substantially completely removed during the dehydrating operation. In a conventional arrangement, waste threads caught by the filter must be removed after the washing operation in order to prevent them from being dried on the filter. However, according to the present invention, although a small quantity of waste threads may be left in the water vessel, the filter surface can always be maintained free from waste threads with a higher rate. Further, since the filter is cleaned by a reverse washing during the draining operation, it is not necessary to make the filter accessible so that it may be positioned below the pulsator 21 and the basket 19.

Claims

I claim:

1. A washing and dehydrating machine comprising a water vessel having a water discharge port at the bottom portion thereof and adapted to be filled with water, a basket provided in the water vessel and having a perforated peripheral wall, a pulsator disposed at the center of the bottom of said basket, a pulsator shaft secured to said pulsator, a basket shaft secured to the bottom portion of said basket, means for selectively transmitting power to said pulsator shaft and said basket shaft, radially extending bead means provided on the back side of the pulsator for providing centrifugal pumping action, water passage means connecting the back side of the pulsator with the space between said water vessel and said basket for introducing the water in said space to the back side of the pulsator, the filter means including a screen of fine mesh rotatable with said basket for screening waste threads in the water flowing in said passage.

2. A washing and dehydrating machine in accordance with claim 1 in which said filter screen is of 20 to 40 mesh.

3. A washing and dehydrating machine in accordance with claim 1 in which said basket shaft is connected with the basket through a flange which is provided with a water port connecting the area around the center of the back side of the pulsator and the space between the basket and the water vessel, the filter of fine mesh size being disposed on the lower surface of said flange so as to cover said water port.

4. A washing and dehydrating machine in accdordance with claim 1 in which the perforations in the basket are provided only in the upper part thereof whereby water in the basket is caused to flow during water draining operation through a water passage connecting the back side of the pulsator and the space between the water vessel and the basket as well as through the filter, after the water in the basket is decreased below a predetermined level.

5. A washing and dehydrating machine comprising a water vessel having a water draining port at the bottom thereof and adapted to be filled with cleaning water, a basket disposed rotatably and concentrically in the water vessel, said basket having perforations in side wall thereof and a recess for mounting a pulsator at the center of the bottom thereof, a flange secured to the lower surface of said recess for connecting a hollow basket shaft and the basket, a pulsator shaft passing through the center of said flange and the basket shaft and secured to the pulsator in said recess, clutch means for selectively transmitting power from a motor either to said pulsator shaft or said basket shaft, a water port provided in said flange, a filter disposed beneath said flange, said pulsator having radially directed ribs on the back side thereof, said ribs producing a circulating water flow through said water port and directed upwardly through said filter when said pulsator is rotated so that waste threads floating in the circulating water are caught by the filter.

6. A washing and dehydrating machine in accordance with claim 5 in which said flange is provided with a plurality of inwardly bent nails, said filter being provided with an outer periphery having an outer diameter which is larger than the diameter of a circle defined by the inner ends of the nails, said filter being also provided with an inner periphery having an inner diameter greater than the outer diameter of a washer interposed between the flange and the basket shaft, said inner periphery of the filter being engaged with the washer and the outer periphery being engaged with said nails.