GB2098713A - Tumbler drier door - Google Patents

Abstract

A tumbler drier includes a door 6 mounted on a front wall 2 of the drier cabinet, which door comprises a moulded baffle dish 12 and a moulded door frame 32. The baffle dish 12 has a base which forms a baffle plate 13 which partly closes an aperture 11 defined by a rim 14 in an end wall of a drier drum 3 which is rotatable about its axis 5. The gap between plate 13 and rim 14 is occupied by a perforated clothes guard ring 15. An air-tight seal between the baffle dish 12 and the front wall 2 of the cabinet is provided by a resilient strip 29 seated in a groove 28 formed in the baffle dish. <IMAGE>

Description

SPECIFICATION Tumbler drier This invention relates to a tumbler drier comprising a cabinet which encloses a drier drum which is rotatable about a horizontal axis, a cabinet door arranged to close an opening in the cabinet in an air-tight manner, a central circular aperture in an end of the drum adjacent the opening, the aperture being so arranged with respect to said opening that articles can be loaded into and removed from the drum when the door is open, which door at least comprises a circular baffle dish which is coaxial with said axis and which extends inwardly of the cabinet such that its base forms a baffle plate which partly closes the aperture when the door is in the closed position, the remaining annular gap between the baffle plate and the rim of the aperture being occupied by a guard ring, integral with the baffle dish, arranged to prevent said articles entering the gap, the guard ring being provided with perforations which allow air to pass relatively freely through the gap.

In such a drier, air is drawn into the cabinet and warmed, whereafter it passes through the drum to dry the articles therein, through the perforations in the guard ring, into an annular duct surrounding the baffle dish, and is then expelled from the machine.

The air is circulated through the drier by a motordriven fan. Since the circulating air is not vented to the atmosphere via the door, it is necessary to have an air-tight seal between the door assembly and the cabinet.

A tumbler drier of the type defined above is disclosed in British Patent Specification 1,434,607. In the embodiment described therein, the door carries a resilient air-sealing strip arranged to engage the flat outer face of the cabinet around the opening at a small distance from the rim of the opening. The door frame is hollow and the baffle dish is provided with a flanged rim which extends into the hollow portion of the door frame and is secured there by the sealing strip. Thus the sealing strip has a double function, namely to hold the baffle dish in the door frame and to provide the door-to-cabinet air seal. However the need to provide a hollow door frame almost inevitably led to its fabrication in sheet metal.Sheet metal constructions tend to be relatively expensive, for example because they have to be protected from corrosion by the hot moisture-laden air and also because they have to be provided with an aesthetically attractive shape and colour. Reasonable protection against corrosion is generally achieved by a stove-enamelled layer on the metal. The enamel layer so provided is, however, fairly easily chipped or scratched. Also, it is very difficult to provide a protective enamel coating inside hollow portions.

Further, the aligning of the door frame, the baffle dish, and the sealing strip is rather a difficult process which cannot readily be automated. As a result, the assembly is time-consuming and expensive.

An object of the invention is to provide a tumbler drier of the above-defined type in which the construction of the door frame, baffle dish, and sealing strip is very considerably simplified.

According to the invention there is provided a tumbler drier of the type defined above, characterised in that, in the vicinity of the opening in the cabinet, the wall of the baffle dish is provided with an annular groove in which a resilient air-sealing strip is seated, the arrangement being such that, with the door closed, the sealing strip provides an air seal directly between the baffle dish and the cabinet.

Thus in a tumbler drier in accordance with the invention, the sealing strip is held in place solely by the baffle dish itself and, therefore, does not have to be located and secured in place by the door frame.

Additionally, the sealing strip may be fixed to the baffle dish at any convenient stage in the overall assembly of the tumbler drier since the application of the sealing strip no longer relies on the presence of the door frame. Thus the baffle dishes may be held in stock with the sealing strip already fixed thereto.

Further, the door frame no longer has to be designed to secure the sealing strip to the frame as well as to the baffle dish in an air-tight manner, since the sealing strip provides an air-tight seal directly between the baffle dish and the cabinet. Indeed, it is possible to provide the baffle dish with a flanged rim having a larger diameter than that of the opening of the cabinet and to shape this rim to have a pleasing appearance and to serve as the door frame. It is customary however to form the baffle dish of a transparent material, in which case the hinge(s) and door latch(es) would be visible through the flange.

Further it is sometimes required that the door frame be square, in which case it is preferable to have a separate door frame.

However, since the frame is effectively freed from the limiting design constraints of the prior art arrangements, the frame can be moulded in a plastics material, thereby eliminating the problems of corrosion and shape limitation. Also, with the use of suitable filler pigments, the door frame can be coloured to substantially any required shade.

The sealing strip may be applied to the groove in the baffle dish from a continuous length of the strip, in which case it has to be accurately cut to length and held in place in the groove, for example by an adhesive. Preferably, however, the open side of the groove faces radially outward of the side of the baffle dish and the sealing strip is ring-shaped with such a diameter that it has to be resiliently stretched in order to seat it in the groove. This has the advantage that no further means are required to hold the resilient strip in place and no cutting to length is necessary. Hence the cost of assembly is considerably reduced.

The arrangement of the groove and sealing strip may be such that the sealing strip engages the cabinet wall solely around the rim of the opening in the cabinet. This has the advantage that the sealing is effected by a wedge action instead of by the direct compression of the seal as used in prior driers. One result is that the very small dimensional tolerances previously required to ensure precise door-tocabinet spacing are no longer necessary. Thus the door hinge(s) and latch(es) may be designed with considerably greater freedom.

In the tumbler drier described in the said patent specificaton, the guard ring is integral with the baffle dish by virtue of being cemented thereto. In an embodiment of the present invention, the guard ring and the baffle dish are formed as a single moulded unit. This achieves yet a further reduction in labour costs during assembly. Also, although the moulding tool for the dish is more complex due to the addition of the guard ring, it is nevertheless more costeffective than the two moulding tools formerly required - particularly since only one moulding cycle is required instead of two and no welding or adhesive process is required.

An embodiment of the invention will now be described with reference to the accompanying drawings, of which Figure 1 shows a schematic sectional view of a tumbler drier and Figure 2 shows, on an enlarged scale, the door and sealing arrangement of the drier shown in Figure 1.

Referring to Figures 1 and 2, a cabinet 1 has a front wall 2 and encloses a drier drum 3 which is rotatable by a motor 4 (via a belt, not shown) about a substantially horizontal axis 5. A cabinet door 6 is hinged, by means not shown, to the front wall 2 and is arranged to close an opening 7, defined by its rim 8, in wall 2 in an air-tight manner. Drum 3 is provided with pivot means 9 at one end and with a central circular aperture 11 at the other end, which aperture is adjacent to and is aligned with opening 7 such that, with door 6 open, articles to be dried can be loaded into drum 3 via opening 7 and aperture 11, and may be subsequently unloaded in a corresponding manner.

Door 6 comprises a circular baffle dish 12 which is arranged coaxiallywith axis 5 and extends inwardly of the cabinet such that its base forms a baffle plate 13 which partly closes aperture 11 when door 6 is in the closed position shown in the figures.

The annular gap between the baffle plate 13 and a rim 14 of drum 3 which defines aperture 11 is occupied by a guard ring 15, moulded integrally with the baffle dish 12 which prevents articles in the drum, when rotating, from entering the gap. Guard ring 15 is provided with perforations 16 which on the one hand are sufficiently small to prevent any small articles from passing through the ring, but on the other hand allowfree passage of air from the drum into a surrounding duct 17 formed by a duct wall 18 and front wall 2 of the cabinet 1.

In use of the tumbler drier, air is drawn into the cabinet, for example via a grill 19 atthe bottom of wall 2, over heating elements 21 arranged at the rear of drum 5, through perforations 22 in the wall of drum 3, through drum 3 and any articles therein to be dried, through the perforations 16 in guard ring 15 into duct 17, and is then drawn through an impeller 23, driven for example by motor 4, and expelled from the cabinet via a venting duct 24.

Alternatively, the air may be blown, instead of sucked, through the drum in a manner shown, for example, in the above-mentioned Patent Specifica tion 1.434,607. The particular arrangements for passing heated air through the drum and guard ring are not relevant to the invention.

The drum 3 is rotationally supported at its front end by a numer of bearer members 25 on which the rim 14 of drum 3 rides. These bearer members 25 are secured to an annular support wall 26 formed on wall 18 of duct 17. The spaces between adjacent bearers may, for example, be filled with a fibrous material 27, such as felt, in order to prevent any air leak from the drum between the bearers.

The side wall of baffle dish 12 has an annular groove 28 formed therein in such a manner that the open side of the groove faces radially outward of the side, in which groove a resilient air-sealing strip 29 is seated. Strip 29, which is of rubber or a rubber-like material, is ring-shaped (i.e. it has the form of a continuous loop) and has such a diameter that, during assembly, it has to be stretched slightly in order to seat it in the groove. With such a loop, no other means such as an adhesive is required in order to retain the sealing strip in position.

With the door 6 closed as shown in the figures, the free edge of the strip 29 remote from the seated portion bears on a flange 31, integrally moulded with baffle dish 12, and the intervening portion of the strip engages, and is resiliently deflected by, the rim 8. Thus the sealing strip 29 forms an air-tight seal directly between the baffle dish 12 and the cabinet wall 2. It is, of course, alternatively possible to provide the groove around the innermost edge of flange 31, but in this case it is possible that an adhesive or clips may be required to hold the sealing strip firmly seated in the groove. Further, the sealing strip may alternatively be arranged such that it engages the flat outer surface of wall 2 instead of solely the rim 8 of the opening.It is not essential for the free edge of the sealing strip 29 to bear on the flange 31 or, indeed, for the sealing strip to have such a free edge. Thus the strip may, for example, be triangular semi-circular in cross section.

A door frame 32, of a moulded plastics material, is secured to the flange 31 by means of self-tapping screws (not shown) which are screwed into respective hollow bosses 33 arranged around the door frame. Since the closure and sealing functions of door 6 are performed by the baffle dish 12, the door frame 32 may be made any suitable shape depending upon the particular hinging and latching arrangement required. Thus the door can be a relatively simple platics moulding.

The baffle dish 12 is preferably moulded in an optically transparent plastics material, for example a styrene acrylonitrile copolymer material, so that the baffle plate 13 servies as a window through which the contents of the drum are visible.

Claims (5)

1. A tumbler drier comprising a cabinet which encloses a drier drum which is rotatable about a horizontal axis, a cabinet door arranged to close an opening in the cabinet in an air-tight manner, a central circular aperture in an end of the drum adjcent the opening, the aperture being so arranged with respect to said opening that articles can be loaded into and removed from the drum when the door is open, which door at least comprises a circular baffle dish which is coaxial with said axis and which projects inwardly of the cabinet such that its base forms a baffle plate which partly closes the aperture when the door is in the closed position, the remaining annular gap between the baffle plate and the rim of the aperture being occupied by a guard ring, integral with the baffle dish, arranged to prevent said articles entering the gap, the guard ring being provided with perforations which allow air to pass relatively freely through the gap, characterised in that, in the vicinity of the opening in the cabinet, the wall of the baffle dish is provided with an annular groove in which a resilient air-sealing strip is seated, the arrangement being such that, with the door closed, the sealing strip provides an air seal directly between the baffle dish and the cabinet.

2. A tumbler drier as claimed in Claim 1, wherein the open side of the groove faces radially outward of the side of the baffle dish and wherein the sealing strip is ring-shaped with such a diameter that it has to be resiliently stretched in order to seat it in the groove.

3. A tumbler drier as claimed in Claim 1 or 2 in which the arrangement of the groove and sealing strip is such that the sealing strip engages the cabinet wall solely around the rim of the opening in the cabinet.

4. A tumbler drier as claimed in Claim 1 or 2 wherein the guard ring and baffle dish are formed as a single moulded unit.

5. A tumbler drier substantially as herein described with reference to the accompanying drawing.