GB2258720A

GB2258720A - Tumble dryer

Info

Publication number: GB2258720A
Application number: GB9117628A
Authority: GB
Inventors: Derek Watts
Original assignee: Creda Ltd
Current assignee: Creda Ltd
Priority date: 1991-08-15
Filing date: 1991-08-15
Publication date: 1993-02-17
Also published as: DE4220534A1; GB9117628D0

Description

1 -5 '537n g Tumble Dryer This invention relates to tumble dryers,

especially to those including a rotatable drum mounted in a cabinet, the drum having an opening at one end for receiving a load.

It is customary for the air which is fed through the drum to dry the load to vent to the atmosphere through a slot in the periphery of the door covering the opening, the slot either opening to the atmosphere outside the cabinet, or opening into a duct inside the cabinet, for venting to the atmosphere or recirculation through the drum. In either case the door includes a filter extending across the area of the opening in the drum through which the emerging air passes, to prevent fluff being blown into the room housing the dryer. However, in order to prevent clothes in the dryer from escaping from the drum, and thus prevent then from rubbing on the filter and causing fluff on the filter to drop back into the drum, the filter is backed by a perforated cover. While this overcomes the problem of fluff build-up dropping back into the drum, to remove the filter or to replace or unblock it now requires the removal of the perforated cover.

P/8662/CRE The invention provides a tumble dryer, comprising a rotatable drum mounted in a cabinet, the drum having an opening at one end for receiving a load, a door for covering the opening, the air leaving the opening being channelled in use into a duct in the cabinet, and a filter positioned in the duct.

By positioning the filter in the cabinet rather than in the door, access to the filter for cleaning or replacement is improved.

Advantageously, the door channels air to the duct and also covers the duct when the door is closed. Thus, for example, the door may have a seal which abuts the front of the cabinet and surrounds the area containing the drum opening and the duct.

The invention is applicable to condenser dryers, in which case the duct includes a condenser, to heat recovery dryers, in which case there is heat exchange between the hot moist air passing down the duct from the drum, and air about to enter the drum, as well as to arrangements in which the hot moist air leaving the drum is simply ducted away.

Tumble dryers constructed in accordance with the P/8662/CRE 3 - invention will now be described, by way of example, with reference to the accompanying drawings, in which:

Figure 1 is a perspective view of a first form of tumble dryer with the door in an open position; and Figure 2 is a perspective view of a second form of tumble dryer with the door in an open position.

Referring to Figure 1, a condenser tumble dryer consists of a rotatable drum 1 having an opening 2 at the front through which the load is inserted, the drum being mounted in a cabinet 3 having a door 4 which is shown in an open position. The drum 1 is rotated by a motor 5 by means of a drive belt which is not shown.

Air is recirculated through the drum, and moisture is extracted from the air in the condenser 6 on each pass and the air is also heated before reentry into the drum. Thus, air is heated in a duct 7 which is fan-shaped in axial view, and enters the rear of the drum in the direction of arrows A. Moisture from the clothes is picked up from the airstream travelling through the drum, and this then leaves the front of the drum and enters a duct 8 located in the cabinet beneath the drum in the direction of arrow B. This f P/8662/CRE - 4 air then passes through a large number of tubes 9 flattened in the horizontal direction over the outside of which a fan 10 driven by the motor 5 blows air drawn from the exterior in the direction of the arrows X. This cooling air passes from side to side of the heat exchanger and emerges from the other end in the direction of arrows Y. The air from which moisture has been removed in the condenser emerges from the rear end of the condenser in the direction of arrows C and travels along duct 11 at the rear of the cabinet where it is fed to the centre of a centrifugal fan 12 (arrow D), and the now dried air is propelled upwardly and heated in the fan shaped duct 7, whereupon it re-enters the drum. The forward end of the tubes 9 is mounted higher than the rear end, so that the moisture condensed out of the airstream drains to the rear of the tubes assisted by the airflow through the tubes, and runs into duct 11. From duct 11, it drains into a removable water bottle 20.

In accordance with the invention, a filter 13 is positioned in the duct 8 in the cabinet (shown in exploded view in Figure 1). The duct is located behind the door of the dryer. The door itself defines the channel for returning the moist air leaving the drum to the recirculation path defined by the duct.

P/8662/CRE Thus, the door is much larger than hitherto on tumble dryers, and has a seal 14 which extends around, not only the opening 2 at the front of the drum, but also around the periphery of the duct 8. The seal 14 abuts the front of the cabinet 3. The door 4 has a projection 15 which extends partially into the open end of the drum in order to prevent rotating clothes from working their way out of the rotating drum, but it does not seal against the opening 2 to allow air to pass around its periphery.

With the condenser dryer of the invention, the filter 13 is readily accessible when the door is open, and it can be removed and cleaned. Very fine particles of fluff can actually pass through the filter and eventually build up on the condenser. However, the condenser is also readily accessible since it is mounted at the front of the dryer, and it may also be removed for cleaning (only this will only be necessary at infrequent intervals). The filter 13 may consist of a gauze for example of plastics material. Because the door itself channels the recirculating air to the duct, the duct can be mounted right at the front of the cabinet, so both filter and condenser are easily accessible.

The invention is not restricted to condenser dryers, and a non-condenser dryer, but which does have a form of A P/8662/CRE - 6 heat recovery, will now be described with reference to Figure 2 of the drawings. Like parts have been given like reference numerals in both drawings.

In the tumble dryer of Figure 2, air leaving the front of the drum and passing into duct 8 is channelled by a path of tapering cross section 16 into a tube of square cross section 17, whereupon it is ducted to the atmosphere by suitable outlets (not shown) in the direction of arrows F. In order to obtain some heat from the air leaving the drum, the air that is drawn into the duct 11 and which passes into the centre of the fan 12 to be blown into the fan-shaped housing 7, is drawn along a box section member 18 communicating with the duct 11 and surrounding the square tube 17 i.e. in the direction of the arrows E. In this way some of the heat which is given to the air in the housing 7 is recovered from the air exhausted along the tube 17. To improve heat transfer, the tube 17 could be finned or corrugated.

With such a non-condenser/dryer, hitherto it would have been customary to provide a circular filter across the area of the door opening to trap fluff, and such a filter would have been backed by a perforated cover to keep the clothes away from the filter. The positioning of the filter I 1 1, P/8662/CRE 13 on the cabinet rather than on the door avoids the need for the perforated cover and provides easier access to the filter.

The invention is also applicable to tumble dryers in which there is no heat recovery i.e. in which the outlet air through the square tubes 17 is vented to the atmosphere and the inlet to the centre of the fan 12 is taken directly from the atmosphere.

Various modifications may be made without departing from the scope of the invention. Thus, in either embodiment the filter 13 could be fixed on the cabinet, or hinged to the cabinet, as a safety feature to prevent removal of it by children. Second, in the first embodiment, the condenser 6 could be mounted above instead of below the drum 1. Some users might prefer a higher positioning of the filter. The duct 11 would be connected to the water bottle 20 by a tube or, if desired, the water bottle 20 could also be mounted above the drum 1 for easier access. Finally, in either embodiment. the air leaving the front of the drum could be channelled to the duct 8 by a double walled region of the front of the cabinet itself, rather than by the door. Thus, the door 4 would only cover the opening at the front of the drum, and there would be a separate opening, perhaps a P/8662/CRE pivoted flap, in front of the duct 8 and filter 13. The region behind the flap and in front of the filter 13 would communicate with the double walled region into which air leaving the drum was fed.

1 P/8662/CRE

Claims

CLAIMS,

1. A tumble dryer,, comprising a rotatable drum mounted in a cabinet, the drum having an opening at one end for receiving a load, a door for covering the opening, the air leaving the opening being channelled in use into a duct in the cabinet, and a filter positioned in the duct.

2. A tumble dryer as claimed in claim 1, in which the filter is movable from the duct to assist cleaning of the filter.

3. A tumble dryer as claimed in claim 1 or claim 2, in which the door is arranged to channel air leaving the opening into the duct, and the door also covers the duct when the door is closed.

4. A tumble dryer as claimed in claim 2, in which the door has a seal which abuts the front of the cabinet.

5. A tumble dryer as claimed in claim 4, in which the seal surrounds both the area of the opening in the drum and the area of the duct.

t 1 41 1 P/8662/CRE 6. A tumble dryer as claimed in any one of claims 1 to 5, in which the duct includes a condenser for withdrawal of moisture from the air leaving the drum, and means is provided to recirculate the dried air into the drum.

t 7. A tumble dryer substantially as herein described with reference to the accompanying drawings.

ANENDLENTS TO TFE CLAM HAVE BEEN FLED AS FOLLOWS -. II - CLAIMS 1. A tumble dryer, comprising a rotatable drum mounted in a cabinet, the drum having an opening at one end for receiving a load, a door for covering the opening, the air leaving the opening being channelled in use into a duct in the cabinet, and a filter positioned in the duct, and accessible from the front of the cabinet.

2. A tumble dryer as claimed in claim 1, in which the filter is a screen arranged substantially parallel to the front of the cabinet.

3. A tumble dryer as claimed in claim 1 or claim 2, in which the filter is movable from the duct to assist cleaning of the filter.

4. A tumble dryer as claimed in any one of claims 1 to 3, in which the door is arranged to channel air leaving the opening into the duct, and the door also covers the duct when the door is closed, the filter thus being accessible when the door is open.

5. A tumble dryer as claimed in claim 4, in which the P/8662/CRE door has a seal which abuts the front of the cabinet.

6. A tumble dryer as claimed in claim 5, in which the seal surrounds both the area of the opening in the drum and the area of the duct.

7. A tumble dryer as claimed in any one of claims 1 to 6, in which the duct includes a condenser for withdrawal of moisture from the air leaving the drum, and means is provided to recirculate the dried air into the drum.

8. A tumble dryer substantially as herein described with reference to the accompanying drawings.