GB2114606A

GB2114606A - Tub to shell gaskets for washing machines

Info

Publication number: GB2114606A
Application number: GB08234886A
Authority: GB
Inventors: Albert Charles Hucker; Alan Mason Roberson
Original assignee: HOOVER PLC
Current assignee: HOOVER PLC
Priority date: 1981-12-07
Filing date: 1982-12-07
Publication date: 1983-08-24
Also published as: GB2114606B

Abstract

The present invention relates to gaskets for front loader washing machines in which the gasket extends between, and seals the tub and the shell of the washing machine. A base (28) and side walls (24 and 26) of the gasket define an annular pocket (18). Two deflector webs (30, 32), peripherally offset from one another, are integrally moulded with a different side wall (24 or 26) and the base (28). The deflector webs (30, 32) are located at 60 degrees away from the lowest point of the loading opening of the washing machine in the direction in which the drum rotates such that when the tub is spun with an article of clothing partially trapped in the pocket, the article of clothing engages and rides over the deflector webs (30, 32) and is thereby expelled from the pocket. <IMAGE>

Description

SPECIFICATION Tub to shell gaskets for washing machines The present invention relates to tub to shell gaskets for washing machines and is concerned with such gaskets for washing machines of front loading type, that is to say of the type having a clothes loading opening in a side surface of the outer casing or shell.

Front loader washing machines include a rotary drum which is mounted to rotate about a substantially horizontal axis within a so called tube, or washing liquid container, which in turn is positioned within the outer casing of the machine. The outer casing is provided with a clothes loading opening in the front surface which may be closed by a movable access door and this opening is substantially aligned with a similar opening in the tube which in turn is aligned with an open end of the rotary drum.The rotational axis of the drum is fixed with respect to the tub and the drum is rotated by a motor positioned between the tub and the outer casing but the tub is mounted in a resilient suspension system to permit it to move in response to radial or axial loads acting on the drum due to the weight of clothes within, it or asymmetrical centrifugal forces when the irregularly loaded drum is spun.

Due to the presence of the clothes loading openings in the outer casing, the tub and the drum there is of necessity a gap between the edges of the opening in the drum and that in the tub and a further such gap between the tub and the outer casing and it is therefore conventional to provide an annular gasket between the tub and the shell or outer casing to ensure that articles of clothing and more particularly water can not pass through the gap between them. This gasket must however permit a substantial amount of relative movement between the tub and the shell since this movement can be as mucbh as 5 cm and the gasket must provide a reliable seal at all times.For this reason the gasket is usually made of extremely resilient material and has a substantial axial length between the tub and the shell which is normally accommodated in convolute or serpentine form between the tub and the shell.

Fig. 1 of the accompanying drawings is an axial section through a conventional tub to shell gasket of rubber. As may be seen, the gasket is in the form of an annular collar and has an annular thickened portion 2 at one end and a further such thickened portion 4 at the other end. The thickened portion 2 has a peripherally extending radial groove 6 which, in use, sealingly accommodates a correspondingly dimensioned flange around the clothes loading opening in the tub of a washing machine, where it is commonly retained in position by an adjustable annular clamp engaging the peripheral surface 8 beside the groove 6. The thickened portion 2 is also provided with a radially inwardly extending peripheral flange 10 which in use axially obscures the small annular gap inevitably present between the tub and the drum.The thickened portion 4 at the other end of the gasket is provided with a peripheral groove 12 which, in use, sealingly accommodates a correspondingly dimensioned flange around the clothes loading opening in the outer shell where it may be retained in position by an adjustable annular clamp engaging the peripheral surface 14 radially outside the groove 12.

The thickened portion 4 is also provided with an inwardly extending peripheral flange 13 which, in use, is sealingly engaged by an inward circular section projection, normally of glass, on the door of the washing machine thereby ensuring that water can not flow from the tub through the clothes loading opening in the shell when the door is closed.

Between the two thickened portions 2 and 4 there is an annular web 16 which under axial tension may adopt a substantially smooth sided tubular form but which is moulded so that in its rest configuration it adopts a convolute or serpentine form defining an annular pocket 18 which communicates with the interior of the gasket through a relatively narrow neck portion 20. The material of the pocket can flex and permit the axial spacing of the two thickened portions to vary by a substantial distance thereby ensuring a reliable seal between the tub and the shell regardless of relative radial or axial movement of these two components.

The gap of the neck portion must be present to permit movement of the tub towards the loading opening in the shell as well as away from it, but articles of clothing tend partially to enter this gap. This is no problem when the machine is washing the clothes since the speed of rotation of the drum is relatively low and the water acts as a lubricant and permits the articles of clothing to slide around in contact with the gasket without damage.However, if the machine switches into its spinning mode the speed of rotation may be 800 r.p.m. or more and, when there is substantially no water present, the friction of the gasket against the portion of the trapped article of clothing trapped in the pocket can severely abrade the article of clothing. ing. In addition, the friction can evaporate the film of water on the gasket and after this the heat generated can be sufficient to melt a portion of the gasket which both reduces the service life of the gasket and leaves a rubber streak across the article of clothing.

According to the present invention a tub to shell gasket for a washing machine of front loading type comprises an annular collar of rubber or elastomeric material, the ends of which are arranged to be sealingly located adjacent aligned clothes loading openings respectively in the tub and shell, the gasket defining a passage between the ends of the gasket, and a portion of the gasket extending in a convolute between the ends of the gasket, the convolute defining an annular pocket opening onto the passage and the gasket including deflector means connected to the inner surface of the pocket and obscuring a major proportion of the axial cross-sectional area of the pocket.

Thus, in use, when the tub is spun with an article of clothing partially trapped in the pocket, the latter engages the deflector means and rides over it and is thereby expelled from the pocket.

The deflector means could -be a solid block with a ramped surface to promote expulsion of an article of clothing from the pocket but it preferably comprises one or more webs extending in a generally radial direction and preferably integrally moulded with the gasket.

The pocket may be considered as being defined by two side walls extending away from the neck of the pocket and being connected by a base portion. It will be appreciated that it is important that the deflector means does not interconnect the two side walls at the neck of the pocket since this would largely prevent relative axial movement of these walls and thus the efficient sealing operation of the gasket. Thus if a single deflector web is provided this may be connected to or integral with the base portion of the pocket or with one or the other of the side walls.In the latter case the web is preferably also connected to or integral with the base portion also since this will tend to mean that when it is engaged by an article of clothing it will yield against its own resilience, or that of the material of the pocket, in a generally tangential direction thus providing a ramp surface which will promote the expulsion of an article of clothing from the pocket.

In the preferred embodiment two deflector webs are provided and whilst these may be coplanar this might result in clothes becoming trapped in the gap between them and they are therefore preferably offset a small distance, e.g. 2 to 10 mm in the peripheral direction.

This permits the two webs to overlap when viewed in axial section and they preferably together obscure substantially the entire crosssection of the pocket. The two webs are preferably connected to, eg, integral with, respective side walls of the pocket and preferably the base portion also, both for added mechanical stability and the reason referred to above. The width of the web or webs is not crucial, but they should be strong enough to withstand substantial mechanical loads and preferably thin enough to yield in the peripheral direction under such load and it is found that a thickness of between 4 and 1 Omm is suitable.

The invention also embraces a washing machine of front loader type incorporating such a gasket and the deflector means of the gasket are preferably located between 20 degrees and 90 degrees away from the lowest point of the loading opening in the direction in which, in use, the drum rotates.

The invention may be carried into practice in various ways but one embodiment will now be described by way of example with reference to the accompanying drawings, in which: Figure 2 is a scrap axial section through the pocket of a gasket along the line Il-Il of Fig.

3, and Figure 3 is a scrap perspective view showing the location of the gasket and deflector means in relation to the tub and shell.

The gasket may be substantially the same as that described in connection with Fig. 1 but includes one pair of deflector webs within the pocket obscuring substantially the entire cross-sectional area of the pocket. As shown in Fig. 2, the pocket may be considered as being defined by two generally outwardly extending wall sections 24 and 26 connected by a base portion 28. Integrally moulded with one side wall 24 and the base 28 is a rubber deflector web 30 which is 6mm thick and obscures approximately three quarters of the cross-sectional area of the pocket. Spaced 6mm in the peripheral direction from the web 30 is a second deflector web 32 which is integrally moulded with the side wall 26 and the base 28, 6mm thick and obscures about half the cross-sectional area of the pocket.

In use, as shown in Fig. 3, the gasket is installed between a tub 34 and a shell of a washing machine with a glass door 40 of the washing machine engaging the flange 13 of the gasket. The deflector webs 30 and 32 are preferably positioned between 20 degrees and 90 degrees and shown at 60 degrees in the Figure, away from the lowest point of the loading openings in the direction in which the drum rotates (shown by arrow 38 in Fig. 3). If a portion of an article of clothing should enter the pocket 18 prior to the drum being spun this will occur at the lower portion of the gasket due to the natural action of gravity.

When the drum spins, the portion of the article of clothing within the pocket is drawn into engagement with the deflector webs 30 and 32. These yield under their natural resilience and present a ramp directed in the direction of rotation and out of the pocket.

The article of clothing rides over the deflector webs and in so doing is drawn out of the pocket. Thus any article of clothing that should become trapped in the pocket is rapidly expelled from it when the drum is spun before the gasket or the article of clothing is damaged. However, the sealing function of the gasket is in no way impaired since the deflector webs do not affect the ability of the walls of the pocket to move relative to one another thereby accommodating relative movement of the tub 34 and shell 36.

Claims

1. A tub to shell gasket for a washing machine of front loading type comprising an annular collar of rubber or elastomeric material, the ends of which are arranged to be sealingly located adjacent aligned clothes loading openings respectively in the tub and shell, the gasket defining a passage between the ends of the gasket, and a portion of the gasket extending in a convolute between the ends of the gasket, the convolute defining an annular pocket opening onto the passage and the gasket including deflector means connected to the inner surface of the pocket and obscuring a major proportion of the axial cross-sectional area of the pocket.

2. A gasket as claimed in Claim 1 in which the deflector means comprises a number of webs extending in a generally radial direction.

3. A gasket as claimed in Claim 1 or Claim 2 in which the annular pocket comprises two side walls extending away from the neck of the pocket and being connected by a base portion.

4. A gasket as claimed in Claim 2 and Claim 3 in which the deflector means comprises a single deflector web connected to the base portion and/or one or other of the side walls.

5. A gasket as claimed in Claim 2 or Claim 3 in which the deflector means comprises two deflector webs connected to different side walls.

6. A gasket as claimed in Claim 5 in which one or both of the deflector webs are connected to the base portion.

7. A gasket as claimed in Claim 5 or Claim 6 in which the deflector webs are offset from one another in the peripheral direction.

8. A gasket as claimed in Claim 7 in which the deflector webs overlap one another when viewed in axial section.

9. A gasket as claimed in Claim 1 in which the deflector means comprises a solid block with a ramped surface.

10. A gasket as claimed in any preceding claim in which the deflector means are integrally moulded with the gasket.

11. A washing machine of the front loader type incorporating a gasket as claimed in any preceding claim.

12. A gasket substantially as herein specifically described with reference to, and as shown in Figs. 2 and 3 of the accompanying drawings.

14. A washing machine as claimed in Claim 13 in which the deflector means of the gasket are located between 20 degrees and 90 degrees away from the lowest point of the loading opening in the direction in which, in use, the drum rotates.