Patent Description:
The invention may be used in the field of garment care.

Garment care devices comprising a steam generator and an opening arranged in the steam generator are known.

An example of such a known device is illustrated in <FIG> and <FIG>. <FIG> depicts an external view of this known garment care device <NUM>, while <FIG> depicts a partial cross-sectional view.

The garment care device <NUM> comprises a housing <NUM>. A steam generator <NUM> is arranged in the housing <NUM>. An opening <NUM> is arranged in the steam generator <NUM> for accessing an inside part of the steam generator <NUM>. A detachable plug <NUM> is used for closing the opening <NUM>. A hose cord 100b is connected between the steam generator <NUM> and an iron 100a.

As shown in <FIG>, the detachable plug <NUM> closes the opening <NUM> by being screw-fitted into a tubular element <NUM> which delimits the opening <NUM>. In the particular example shown in <FIG>, the tubular element extends from the steam generator <NUM> towards the housing <NUM>.

In this type of garment care device <NUM>, the opening <NUM> is intended to operate a de-calc or rinse of the steam generator <NUM>. Indeed, when water is heated and then evaporates in the steam generator <NUM>, scale may overtime accumulate in the steam generator <NUM>.

When the plug <NUM> is removed from the opening <NUM>, scale can be discharged together with the remaining water full of minerals, for example into a sink or a cup. Note that the plug <NUM> is sometimes provided at its extremity with a spoon or scraper element <NUM> used to free the path of the opening <NUM> if there is a relatively large amount of accumulated scale, which may occur, for example, when the user does not regularly rinse the steam generator <NUM>.

Although this known type of garment care device <NUM> greatly helps the user to de-scale/de-calc the steam generator <NUM>, and thus helps to extend the lifetime of the device <NUM>, the user is usually advised to conduct this operation with care. Typically, the user is asked to switch off and unplug the device <NUM> from the power supply, to allow it to cool down for an hour after the previous use. Such guidance is, for example, explained in the user manual of the garment care device <NUM>.

However, in cases where the user does not follow these recommendations, in particular does not wait a sufficient amount of time after the previous use of the device <NUM>, this de-scaling process may entail risks to the user. Indeed, if the steam generator <NUM> is still hot and contains steam under pressure, when the user starts to remove the plug <NUM>, some steam SS might be projected towards the user's hand. In such a scenario, there is a risk of injury to the user because the user may be scalded by the steam SS.

<CIT> discloses a household ironing appliance comprising a steam generator provided with a discharge opening.

<CIT> discloses an electrical household appliance for producing and feeding steam to an electric iron.

<CIT> discloses an electrical heating element having a heating conductor for heating water, and a carrier element for receiving the heating conductor. The carrier element is deformed reversibly by a temperature change, and the deformation is transferred to the heating conductor.

<CIT> discloses a method for cleaning an iron provided with a scale recovery cavity.

It is an object of the invention to provide a detachable plug, and in particular a garment care device comprising such a detachable plug, that avoids or mitigates the above-mentioned problems.

To this end, the garment care device according to the invention comprises: a steam generator,.

At or above the given temperature threshold, the mechanism prevents detachment of the plug from the steam generator. Only once the steam generator has cooled below the given temperature threshold is the plug capable of being removed by the user. The safety of the device is correspondingly improved.

Particular aspects of the invention will now be explained with reference to the embodiments described hereinafter and considered in connection with the accompanying drawings, in which identical parts or sub-steps are designated in the same manner:.

The present invention relates to a detachable plug for accessing the inside of a steam generator of a garment care device. The plug is detachable from the steam generator by rotation via a thread. The plug comprises a mechanism having mechanical movements being dependent on the temperature of the steam generator, such that when the temperature of the steam generator is equal to or above a given temperature threshold, the mechanism is adapted to prevent the plug from being detached from the steam generator. In other words, when the temperature of the steam generator is below the given temperature threshold, the mechanism is adapted to allow the plug to be detached from the steam generator.

In an embodiment, the plug comprises a first part and a second part. The second part comprises a threaded portion for engaging with a complementary threaded portion provided around an opening of the steam generator.

The first part is rotatable by the user. To this end, the first part can be coupled to a handle, e.g. a knob, which can be grasped by the user, and used to rotate the first part.

In this embodiment, the mechanism is configured such that the first part and the second part are keyed, i.e. locked, to each other when the temperature of the steam generator is below the given temperature threshold, such that user rotation of the first part causes rotation of the second part to allow the plug to be detached from the steam generator. The mechanism is further configured such that the first part and the second part are not keyed to each other when the temperature of the steam generator is equal to or above the given temperature threshold.

The first and second parts being keyed to each other below the given temperature threshold means that rotation of the first part by the user also causes the second part to rotate. Accordingly, when the temperature is sufficiently low, the torque applied by the user to the first part is transferred to the second part engaged to the opening of the steam generator via the threaded coupling, thereby to loosen the thread (when the first part is being twisted in the appropriate direction).

At or above the given temperature threshold, the first and second parts are not keyed to each other such that user rotation of the first part does not cause rotation of the second part. Rather, the first part merely rotates relative to the second part when the temperature is at or above the given temperature threshold.

This may improve user safety because the temperature of the steam generator is required to fall below the given temperature threshold before the mechanism permits detachment of the plug.

Preferably, the given temperature threshold is in the range [<NUM>; <NUM>] °C. Such a temperature threshold assists to ensure that the plug is only detachable when the scalding risk to the user is reduced.

The first part and the second part can be keyed to each other in any suitable manner. In an embodiment, the mechanism comprises a sliding element arranged to slide between a first position in which the sliding element keys the first part to the second part, and a second position in which the sliding element does not key the first part to the second part. The sliding element's adoption of the first or second position in this example is dependent on the temperature of the steam generator.

The mechanism comprises a reversibly thermally deformable element whose expansion (i.e. increase in length) when the temperature of the steam generator is equal to or above the given temperature threshold causes the mechanism to prevent the plug from being detached from the steam generator. The decrease of length of the reversibly thermally deformable element when the temperature of the steam generator is below the given temperature threshold causes the mechanism to allow the plug to be detached from the steam generator.

Preferably, the reversibly thermally deformable element is arranged such that its expansion when the temperature of the steam generator is equal to or above the given temperature threshold causes the first part to be no longer keyed to, i.e. unlocked from, the second part.

This expansion is nevertheless reversible such that when the temperature of the steam generator falls below the given temperature threshold, the associated contraction of the reversibly thermally deformable element assists to cause the first part to be again keyed to the second part. In other words, the reversibly thermally deformable element returns to its original compressed shape.

Suitable materials which can be used for the reversibly thermally deformable element are known. They are sometimes referred to as shape memory material. Particular mention is made of nickel titanium alloy, also known as Nitinol.

The nickel titanium alloy has, for example, a concentration of nickel of approximately <NUM> to <NUM> mole%, <NUM> to <NUM> wt. %, and a concentration of titanium of <NUM> to <NUM> mole%, <NUM> to <NUM> wt. The given temperature threshold can be tuned by making small changes to the concentrations of nickel and titanium in the alloy.

Preferably, the reversibly thermally deformable element is in the form of a spring, such as a helical spring. This spring is also referred to herein as a "first spring". This first spring may assist to control the direction, e.g. predominant direction, of movement of the reversibly thermally deformable element.

In the case of the first spring being a helical spring, the reversible deformation expansion of the helical spring causes axial lengthening/shortening of the helical first spring. This (predominantly) axial movement can usefully be applied to engaging/removing the keying between the first and second parts.

The first spring may, for example, be a helical nickel titanium alloy spring.

The given temperature threshold to which the reversibly thermally deformable element is heated in order to increase its length in order to unlock the first part from the second part may be different from the temperature to which the element must be cooled in order to subsequently restore the mechanical key between the first and second parts. The latter temperature is nonetheless lower than the given temperature threshold such that the first and second parts are keyed to each other below the given temperature threshold.

In the case of the helical nickel titanium alloy spring, the axial elongation of the spring may occur when temperature reaches or exceeds <NUM> and it can be compressed back to a shorter length when the temperature decreases below <NUM>.

Preferably, the mechanism comprises a second spring <NUM> for biasing the first and second parts into engagement with each other below the given temperature threshold. In this case, the resistance of the second spring is overcome by the increase of length of the above-described reversibly thermally deformable element when the temperature is equal to or above the given temperature threshold.

The second spring may be formed of any suitable material, such as stainless steel. The second spring is not intended to axially lengthen and contract to the same degree as the reversibly thermally deformable material in the relevant temperature range of the steam generator. The second spring <NUM> may also be situated further away from the steam generator than the first spring when the plug is closing the opening.

Thus, the increase in length of the reversibly thermally deformable element, e.g. the first spring, overcomes the resistance of the second spring in order to remove the keying of the first part with the second part at or above the given temperature threshold.

When the steam generator has cooled sufficiently, the second spring forces reengagement of the first and second parts by compressing the reversibly thermally deformable element.

In an embodiment, the mechanism comprises a hollow housing and the above-described sliding element slides within the hollow housing between the first position in which the first and second parts are keyed with each other and the second position in which the first and second parts are not keyed with each other.

The hollow housing is, for example, a hollow cylinder, i.e. a hollow cylindrical housing, although other shapes for the housing can be envisaged.

Preferably, the sliding element is arranged relative to the reversibly thermally deformable element such that the sliding element moves from the first position to the second position by increase of length of the above-described reversibly thermally expandable element at or above the given temperature threshold. For example, this movement can be effected by axial increase of length of a helical spring formed from a suitable reversibly thermally deformable material, such as nickel titanium alloy.

Preferably, the second part comprises an inside bottom part of the hollow housing, and the sliding element comprises a first extremity adapted to lock with the inside bottom part when the temperature of the steam generator is below the given temperature threshold.

The term "inside bottom part" is intended to refer to a part which is proximal to the opening of the steam generator and distal with respect to the portion of the plug, e.g. handle, which the user turns in order to gain access to the steam generator.

The inside bottom part and the sliding element may experience relatively high torsion stress during operation. Hence, they are preferably made from high strength materials, such as SUS304 stainless steel, whose yield strength is around 215MPa.

In this embodiment, the first part comprises a rotating shaft. A second extremity of the sliding element is adapted to permanently slidably lock with the rotating shaft. In other words, the sliding element is engaged with the rotating shaft via the second extremity of the sliding element irrespective of the temperature of the steam generator.

When the temperature of the steam generator is at or above the given temperature threshold, the increase of length of the reversibly thermally deformable element causes the sliding element to be positioned such that the first extremity of the sliding element and the inside bottom part become unlocked from each other.

Thus, rotation of the rotating shaft by the user is not transferred to the inside bottom part (and the hollow housing) when the temperature is at or above the given temperature threshold.

In the example in which the reversibly thermally deformable element is defined by the above-described first spring, the length of the first spring at or above the given temperature threshold is such that the first extremity of the sliding element and the inside bottom part are unlocked.

Preferably, the reversibly thermally deformable element, e.g. the first spring, is arranged inside the hollow housing. The reversibly thermally deformable element is thus shielded by the hollow housing from the water and/or steam present in the steam generator. The housing can therefore protect the reversibly thermally deformable element from being fouled by scale.

Preferably, the housing is formed from a material having relatively high thermal conductivity, combined with sufficient strength and corrosion resistance. Suitable materials for forming the housing thus include aluminum or brass. Aluminum has a thermal conductivity of around <NUM> W/mK, and brass has a thermal conductivity about <NUM> W/mK (<NPL>). Such a material can assist heat transfer from the steam/water within the steam generator into the interior of the hollow housing of the plug. This effective heat transfer, in turn, facilitates unlocking of the first part from the second part of the mechanism when the temperature of the steam generator is at or above the given temperature threshold.

In an example, the hollow housing comprises a first portion coupled to a second portion. In this example, the second portion comprises the threaded portion for engaging with the complementary threaded portion delimiting the opening of the steam generator.

Such a two-portion hollow housing may facilitate assembly of the plug.

Preferably, the first spring is arranged inside the second portion. In this example, at least the second portion is formed of the material having relatively high thermal conductivity, combined with sufficient strength and corrosion resistance, e.g. aluminum or brass.

In this manner, the heat from the steam generator is transmitted to the first spring via the second portion of the hollow housing.

In other examples, the hollow housing takes the form of a unitary component.

In an embodiment, the reversibly thermally deformable element, e.g. the first spring, is arranged inside the steam generator when the plug is attached thereto. Locating the reversibly thermally deformable element inside the stream generator in this manner facilitates transfer of heat to the reversibly thermally expandable element, which may enhance the responsiveness of the mechanism to the temperature of the steam generator.

Upon the temperature of the steam generator falling below the given temperature threshold, the decrease of length of the reversibly thermally deformable element assists to cause the first extremity and the bottom part to again become locked, i.e. keyed, to each other.

In the example in which the reversibly thermally deformable element is defined by the above-described first spring, the (compressed) length of the first spring below the given temperature threshold is such that the first extremity of the sliding element and the inside bottom part are locked to each other. The reversion to this locked state can also be assisted by the second spring, as previously described.

The first spring exerts a first force on the first extremity of the sliding element, and the second spring exerts a second force on the second extremity of the sliding element. The second force is applied in the opposite direction to the first force.

The first spring is such that the first force is greater than the second force when the temperature of the steam generator is at or above the given temperature threshold, and the second spring is such that the second force is greater than the first force when the temperature of the steam generator is below the given temperature threshold.

In a particular example, the mechanism comprises the hollow housing, and the hollow housing has the inside bottom part. The mechanism further includes a rotating shaft connected to a user handle, and the sliding element adapted to slide inside the hollow housing. In this example, the rotating shaft and the handle define the previously described first part of the plug, and the hollow housing and the inside bottom part define the second part of the plug. The sliding element comprises a first extremity adapted to lock with the inside bottom part, and a second extremity adapted to permanently slidably lock with the rotating shaft. The mechanism further comprises the first spring arranged inside the hollow housing for exerting the first force on the first extremity, and the second spring is also arranged inside the hollow housing for exerting the second force on the second extremity. The second force is opposite to the first force, as previously described.

The first spring is thermally deformable such that:.

More generally, the releasable locking of the first extremity of the sliding element and the inside bottom part may be implemented in any suitable manner. In a first example, the inside bottom part comprises a first pin protruding in the direction of the first extremity. In this case, the first extremity comprises a first cavity adapted to lock with the first pin.

The first pin may, for example, form a peg which can be received within the first cavity included in the first extremity of the sliding element.

Preferably, the first pin is of a non-circular cross-sectional shape, and the first cavity has a cross-sectional shape complementary to the non-circular cross-sectional shape. This facilitates locking of the first pin and the first cavity when the temperature of the steam generator is below the given temperature threshold.

The first pin can have any suitable non-circular cross-sectional shape, such as square, rectangular, hexagonal, triangular, crossed, D-shape, etc..

In a second example, the first extremity comprises a second pin protruding in the direction of the inside bottom part. In this case, the inside bottom part comprises a second cavity adapted to lock with the second pin.

The second pin may, for example, form a peg which can be received within the second cavity included in the inside bottom part.

Preferably, the second pin is of a non-circular cross-sectional shape, and the second cavity has a cross-sectional shape complementary to the non-circular cross-sectional shape. This facilitates locking of the second pin and the second cavity when the temperature of the steam generator is below the given temperature threshold.

The second pin can have any suitable non-circular cross-sectional shape, such as square, rectangular, hexagonal, triangular, crossed, D-shape, etc..

<FIG> and <FIG> provide cross-sectional views of a detachable plug <NUM> according to a non-limiting example. The plug <NUM> shown in <FIG> and <FIG> is closing an opening <NUM> which provides access to a steam generator <NUM> of a garment treatment device <NUM> when the plug <NUM> is detached from the steam generator <NUM>.

The plug <NUM> comprises a hollow housing <NUM>, which in this example takes the form of a hollow cylinder. The hollow housing <NUM> has an inside bottom part <NUM>.

In this example, the inside bottom part <NUM> comprises a first pin 111A.

The inside bottom part <NUM> is affixed, e.g. permanently locked, to the hollow housing <NUM>. An annular portion <NUM> of the inside bottom part <NUM> is fitted into a complementary engagement member <NUM> of the hollow housing <NUM>.

The inside bottom part <NUM> can, for example, be mounted to the engagement member <NUM> of the hollow housing <NUM> via a screw mechanism. The screw mechanism may also be fixed, e.g. jammed, via the application of a suitable strong adhesive, such as locktite® from Henkel AG & Company, KGaA.

In other examples, the inside bottom part <NUM> and the hollow housing <NUM> are integrally formed.

The plug <NUM> further comprises a rotating shaft <NUM>. A first end <NUM> of the rotating shaft <NUM> is engaged with, e.g. permanently locked to, a complementary recess <NUM> in a handle <NUM>. Rotation of the handle <NUM> by the user thus causes the rotating shaft <NUM> to rotate, irrespective of the temperature of the steam generator <NUM>.

The handle <NUM> can have any suitable shape, provided that the user is able to grasp the handle <NUM> and rotate the rotating shaft <NUM> using the handle <NUM>. For example, the plug <NUM> shown in <FIG> and <FIG> has a handle <NUM> in the form of a knob.

In this example, the handle <NUM> and the rotating shaft <NUM> at least partly define a first part <NUM>, <NUM> of the plug <NUM>. Moreover, the hollow housing <NUM> and the inside bottom part <NUM> at least partly define a second part <NUM>, <NUM> of the plug <NUM>.

It is noted that a relatively small gap tolerance can be provided between the hollow housing <NUM> and the rotating shaft <NUM>. Such a relatively small gap tolerance is acceptable in this case because the rotating shaft <NUM> is not intended to axially slide relative to the hollow housing <NUM>.

As shown in <FIG>, when the temperature of the steam generator <NUM> is less than a given temperature threshold T1, the first part <NUM>, <NUM> is keyed to the second part <NUM>, <NUM>. The second part <NUM>, <NUM>, and in particular the hollow housing <NUM>, is engaged via a threaded coupling <NUM> to the tubular element <NUM>. Turning the handle <NUM> in the appropriate direction, e.g. anticlockwise, enables loosening and removal of the hollow housing <NUM> from the tubular element <NUM>.

The plug <NUM> comprises a mechanism having mechanical movements being dependent on the temperature of the steam generator <NUM>.

When the temperature of the steam generator <NUM> is equal to or above the given temperature threshold T1, as shown in <FIG>, the mechanism is adapted to prevent the plug <NUM> from being detached from the steam generator <NUM>. When the temperature of the steam generator <NUM> is below the given temperature threshold T1, the mechanism is adapted to allow the plug to be detached from the steam generator, as shown in <FIG>.

In the example depicted in <FIG> and <FIG>, the mechanism comprises a sliding element <NUM>. The sliding element <NUM> slides within the hollow housing <NUM> between a first position in which the first part <NUM>, <NUM> and the second part <NUM>, <NUM> are keyed with each other, as shown in <FIG>, and a second position in which the first part <NUM>, <NUM> and the second part <NUM>, <NUM> are not keyed with each other.

The sliding element's <NUM> adoption of the first or second position is dependent on the temperature of the steam generator <NUM>. In this example, this is achieved thermo-mechanically via the change of length of a reversibly thermally deformable element. This has the benefit of simplicity and low cost manufacture, although any suitable alternative thermal actuation principle can be used.

In the example shown in <FIG> and <FIG>, the reversibly thermally deformable element is in the form of a first spring <NUM>, helical-shaped and formed from nickel titanium alloy. This first spring <NUM> is shown in a compressed shape in <FIG>, and in an expanded state in <FIG>. Change in length of the nickel titanium alloy is sufficient when the temperature is equal to or exceeds the given temperature threshold T1 to cause the first part <NUM>, <NUM> to be unlocked from the second part <NUM>, <NUM>.

The sliding element <NUM> has a first extremity <NUM> and a second extremity <NUM>.

The second extremity <NUM> of the sliding element <NUM> is adapted to permanently slidably lock with the rotating shaft <NUM>. In other words, the sliding element <NUM> is engaged with the rotating shaft <NUM> via the second extremity <NUM> irrespective of the temperature of the steam generator <NUM>.

This is achieved in the example shown in <FIG> and <FIG> by the second extremity <NUM> of the sliding element <NUM> comprising a recess 129A in which a second end 129B of the rotating shaft <NUM> is located, irrespective of the movement of the sliding element <NUM> caused by the temperature changes of the steam generator <NUM>.

In other words, the sliding element <NUM> is always in contact with the rotating shaft <NUM>, so the alignment between the sliding element <NUM> and the rotating shaft <NUM> is maintained throughout the range of movement of the sliding element <NUM>.

The first extremity <NUM> of the sliding element <NUM> is adapted to lock with the inside bottom part <NUM> when the temperature of the steam generator is below the given temperature threshold T1, as shown in <FIG>.

However, when the temperature of the steam generator <NUM> is at or above the given temperature threshold T1, the expansion/lengthening of the first spring <NUM> causes the sliding element <NUM> to be positioned such that the first extremity <NUM> of the sliding element <NUM> and the inside bottom part <NUM> become unlocked, as shown in <FIG>.

Thus, rotation of the rotating shaft <NUM> by the user is not transferred to the inside bottom part <NUM> (and the hollow housing <NUM>) when the temperature is at or above the given temperature threshold T1. Since this prevents the user from removing the plug <NUM>, the plug <NUM> improves user safety, as previously described.

In the example shown in <FIG> and <FIG>, the mechanism comprises a second spring <NUM> for biasing the first part <NUM>, <NUM> into engagement with the second part <NUM>, <NUM> below the given temperature threshold T1.

The first spring <NUM> exerts a first force F1 on the first extremity <NUM> of the sliding element <NUM>, and the second spring <NUM> exerts a second force F2 on the second extremity <NUM> of the sliding element <NUM>. The second force F2 is applied in the opposite direction to the first force F1.

The first spring <NUM> is such that the first force F1 is greater than the second force F2, i.e. the spring force of the second spring <NUM>, when the temperature of the steam generator <NUM> is above the given temperature threshold T1. The second spring <NUM> is such that the second force F2 is greater than the first force F1 when the temperature of the steam generator <NUM> is below the given temperature threshold T1.

The first spring <NUM>, e.g. formed form the nickel titanium (Nitinol) alloy, acts like a temperature sensor. When the first spring <NUM> is exposed to elevated temperatures, it changes its geometry and decouples the first part <NUM>, <NUM> from the second part <NUM>, <NUM>, thus preventing the user from removing the plug <NUM>.

At lower temperatures, the first spring is compressed to its original compressed shape/geometry, for example with the help of the second spring <NUM>. This assists the first part <NUM>, <NUM> to be recoupled to the second part <NUM>, <NUM>, thus enabling the user to unscrew the plug <NUM>.

The sizing and spring constant of the second spring <NUM> may allow the reversibly thermally deformable element, e.g. the nickel titanium (Nitinol) alloy, to extend sufficiently when in a relatively hot environment, as well as provide a strong enough compressive force to return the first spring <NUM> to its original compressed shape when the environment cools down. At this same time, the sliding element <NUM> is pushed back towards the inside bottom part <NUM>.

<FIG> illustrates the characteristics of a reversibly thermally deformable element used in a garment care device according to the invention.

The reversibly thermally deformable element corresponds to the first spring <NUM>, made of Nitinol alloy, when interacting with and under the effect (i.e. force) of the second spring <NUM>. The variations of length of the first spring <NUM> are thus measured for various increasing/decreasing temperatures of the assembly first spring <NUM> / second spring <NUM>.

The horizontal axis corresponds to the temperature around the assembly first spring <NUM> / second spring <NUM>.

The vertical axis corresponds to the change of length of the first spring <NUM>.

Note that the temperature of the assembly first spring <NUM> / second spring <NUM> may be relatively different than the temperature of the steam generator itself. Indeed, the first spring <NUM> is encapsulated in the plug which acts as a thermal resistance.

In this example, the second spring <NUM> has a spring constant of <NUM>.

As illustrated, the first spring <NUM> does not behave in a symmetrical manner to a temperature increase or a temperature decrease.

In other words, the plug starts to be detachable from the steam generator at a temperature being different than the given temperature threshold T1 of the steam generator.

For example, using a first spring <NUM> and a second spring <NUM> having the characteristics of <FIG> when cooperating together:.

In the example shown in <FIG> and <FIG> (as well as in the examples shown in <FIG>, <FIG>, <FIG>), the inside bottom part <NUM> comprises a first pin 111A. In the detachable plug <NUM>, the first pin 111A protrudes in the direction of the first extremity <NUM>.

As best shown in <FIG>, the first extremity <NUM> comprises a first cavity 127A which is adapted to lock with the first pin 111A. The first pin 111A may, for example, form a peg which can be received within the first cavity 127A.

<FIG> provides a perspective view of a detachable plug <NUM> according to another example. <FIG> provides an exploded view of the detachable plug <NUM> shown in <FIG>. In this example, the hollow housing <NUM> comprises a first portion 108A coupled to a second portion 108B. The second portion 108B comprises the threaded portion for engaging with the complementary threaded portion delimiting the opening <NUM> of the steam generator <NUM>.

Such a two-portion hollow housing 108A, 108B may facilitate assembly of the plug <NUM>.

In this example, a screw hole <NUM> in the handle <NUM> enables the handle <NUM> to be secured to the rotating shaft <NUM> such that rotation of the handle <NUM> causes rotation of the rotating shaft <NUM>, as previously described.

As shown in <FIG>, the plug <NUM> has a retaining ring <NUM>, e.g. a circlip, which retains the rotating shaft <NUM> in the hollow housing <NUM>.

The first and second portions 108A, 108B in this example are coupled to each other via a threaded joint (not visible). The hollow housing 108A, 108B in this example has a substantially cylindrical shape. A first recessed region <NUM> in the exterior surface of the first portion 108A and a second recessed region <NUM> in the exterior surface of the second portion 108B mean that the exterior shape of the hollow housing 108A, 108B is not precisely cylindrical, but the first and second recessed regions <NUM>, <NUM> nonetheless facilitate tightening of the threaded joint by accommodating a suitable tool, such as a wrench.

In the example shown in <FIG> and <FIG>, a seal holder <NUM>, e.g. an O-ring holder <NUM>, is fitted to the second portion 108B. This seal holder <NUM> is for carrying a seal, e.g. an O-ring, provided between the hollow housing 108A, 108B and the tubular element <NUM> delimiting the opening <NUM> of the steam generator <NUM>. This arrangement assists to seal the steam generator <NUM> when the plug <NUM> is attached thereto.

Whilst not visible in <FIG>, <FIG>, <FIG>, and <FIG>, the plug <NUM> can comprise a scraper element <NUM> to assist with removal of scale from the steam generator <NUM>. For example, such a scraper element <NUM> may be attached to the hollow housing <NUM> and extend into the steam generator <NUM> via the opening <NUM> when the plug <NUM> is attached to the steam generator <NUM>.

<FIG> provide views of a sliding element <NUM> of an exemplary detachable plug <NUM>. The perspective view provided in <FIG> shows the first cavity 127A in which the first pin 111A of the inside bottom part <NUM> is locatable.

The perspective view provided in <FIG> shows the recess 129A of the sliding element <NUM> in which the second end 129B of the rotating shaft <NUM> is located, throughout the range of movement of the sliding element <NUM>, as previously described.

As shown in <FIG>, the recess 129A has a non-circular, e.g. polygonal, cross-sectional shape, and this is complemented by the cross-sectional shape of the second end 129B of the rotating shaft <NUM>. Thus, rotation of the rotating shaft <NUM> is transferred to the sliding element <NUM>, and in turn to the hollow housing <NUM> when the temperature of the steam generator <NUM> is below the given temperature threshold T1.

In the example shown in <FIG>, the first cavity 127A has a non-circular cross-sectional shape. The non-circular, e.g. polygonal, cross-sectional shape of the first cavity 127A complements the cross-sectional shape of the first pin 111A, as shown in <FIG>. Thus, the non-circular cross-sectional shape of the first pin 111A and the first cavity 127A in this example facilitates locking of the first extremity <NUM> with the inside bottom part <NUM> when the temperature of the steam generator <NUM> is below the given temperature threshold T1.

<FIG> provides view of the inside bottom part <NUM> which shows an indent <NUM>. This indent <NUM> is for receiving a suitable tool, such as a screw driver, to enable securement of the inside bottom part <NUM> to the hollow housing <NUM> via a screw mechanism, as previously described.

The sliding element <NUM> preferably slides freely in the hollow housing <NUM> to minimize the risk of the sliding element <NUM> becoming jammed inside the hollow housing <NUM>. Also, the first cavity 127A in the sliding element <NUM> is ideally large enough to always engage the first pin 111A when the first spring <NUM> is exposed to temperatures lower than the given temperature threshold T1. At the same time, the first cavity 127A is required to be able to transfer the turning torque from the handle <NUM> to the first pin 111A to enable the user to unscrew the plug <NUM>.

Sufficient tolerance is given to the sliding interface between the first cavity 127A and the first pin 111A such that when the first cavity 127A is aligned to the first pin 111A, the sliding element <NUM> will always re-engage the first pin 111A.

Stack tolerance calculations can be carried out to ensure that the first cavity 127A in the sliding element <NUM> is large enough to ensure that the sliding element <NUM> can always slide back into engagement with the first pin 111A, yet small enough to ensure the sliding element <NUM> can transfer the turning force to the first pin 111A.

It is noted that following cooling of the steam generator <NUM>, there is a possibility of the above-described non-circular cross-sectioned first cavity 127A of the sliding element <NUM> not being aligned with the non-circular cross-sectioned first pin 111A. For example, the sliding element <NUM> may be rotated at <NUM>° relative to the inside bottom part <NUM> such that the first pin 111A cannot be located into the first cavity 127A. But in this case, turning of the handle <NUM> to the appropriate degree, e.g. by <NUM>° in the same example, will enable the second spring <NUM> to cause the sliding element <NUM> to be pushed back towards the inside bottom part <NUM> when the first cavity 127A becomes re-aligned with the first pin 111A.

Analogous alignment considerations are applicable to the alternative sliding element <NUM>/inside bottom part <NUM> configuration shown in <FIG>. In this case, the first extremity <NUM> of the sliding element <NUM> comprises a second pin 111B which protrudes in the direction of the inside bottom part <NUM>. In this configuration, the inside bottom part <NUM> comprises a second cavity 127B adapted to lock with the second pin 111B.

The second pin 111B may, for example, form a peg which can be received within the second cavity 127B. Preferably, the second pin 111B has a non-circular, e.g. polygonal, cross-sectional shape, and the second cavity 127B has a cross-sectional shape complementary to the non-circular shape. This facilitates locking of the first extremity <NUM> with the inside bottom part <NUM> when the temperature of the steam generator <NUM> is below the given temperature threshold T1, as previously described.

The plug <NUM> according to the invention is mounted to the steam generator <NUM> similarly as the plug illustrated in <FIG>.

<FIG> depicts a cross-sectional view of a garment care device according to the invention,.

<FIG> depicts a top view of a garment care device according to the invention.

Claim 1:
A garment care device (<NUM>) comprising:
a steam generator (<NUM>),
a plug (<NUM>) arranged on said steam generator (<NUM>) to access the inside of said steam generator (<NUM>), said plug (<NUM>) being detachable by rotation via a thread,
characterised in that the plug (<NUM>) comprises a mechanism having mechanical movements being dependent on the temperature of said steam generator (<NUM>), such that when the temperature of said steam generator (<NUM>) is equal to or above a given temperature threshold (T1), said mechanism is adapted to prevent the plug (<NUM>) from being detached from the steam generator (<NUM>), wherein the mechanism comprises a reversibly thermally deformable element whose expansion when the temperature of the steam generator (<NUM>) is equal to or above the given temperature threshold (T1) causes the mechanism to prevent the plug (<NUM>) from being detached from the steam generator (<NUM>), and whose contraction when the temperature of the steam generator (<NUM>) is below the given temperature threshold (T1) causes the mechanism to allow the plug (<NUM>) to be detached from the steam generator (<NUM>).