heating closet comprising such heating support

The present invention relates to a heating support for objects to be heated and a heating closet comprising such heating support.

Such heating supports are well known. Typically, they are water-filled or oil-filled metal radiators with an electric heating element in the form of an electric cartridge inserted into the water-filled or oil-filled metal radiator. The heat transport within such radiators primarily works by convection within the water or oil with some contribution by heat conduction primarily within the metal walls of these radiators. The heating of the air surrounding such radiators primarily works by natural or forced convection and by radiation.

In order for convection within such type of radiator to work well, it has to be arranged with as much level difference between its uppermost portions and its lowermost portions. For typical box-like, plate-like, grid-like or comb-like radiators having a maximum dimension along a first radiator main axis, a medium dimension along a second radiator main axis and a minimum dimension along a third radiator main axis, this means that they have to be arranged at a wall or the floor of a room with their first or second main axis extending in a vertical direction to achieve reasonable convection and a uniform temperature at the radiator surface. In addition, when some air is left in the radiator it may form pockets of air blocking the flow of liquid in some portions of the radiator. As a result, convective liquid flow within the radiator may be seriously impaired and further contribute to non-uniform temperature at the radiator surface. Finally, due to the arrangement of the first or second main radiator axis extending in a vertical direction, such type of radiator provides a relatively small support area on top of the radiator for placing objects to be heated.

It is an object the present invention to provide a radiator which does not suffer from these drawbacks. Therefore, the present invention provides a heating support for objects to be heated, said heating support comprising a plurality of support elements arranged next to each other and together providing a support base for objects to be placed thereon, wherein at least some, preferably all, of said support elements comprise a hermetically sealed cavity filled with a fluid and having a first cavity portion thermally connected to at least one heat source and a second cavity portion thermally connected to at least one heat sink, said first cavity portion and said second cavity portion being in fluid connection with each other to allow liquid or steam to flow between the two cavity portions. According to the invention, the fluid can be evaporated in said first cavity portion with heat energy provided by said heat source and said fluid can be condensed in said second cavity portion, thus providing heat to said heat sink.

As a result, irrespective of the position or spatial orientation of the heating support, the evaporated fluid portion (steam) of the fluid will spread uniformly within the hermetically sealed cavity, thus contributing to a uniform temperature distribution at the radiator surface. In addition the condensed fluid portion (liquid) of the fluid provides condensation heat at the heat sink at a location different from the heat source and can flow back to the heat source. The steam uniformly distributed within the hermetically sealed cavity contributes to a uniform temperature distribution, within the cavity and at the surface of the support elements which form a radiator surface.

In the heating support, at least some, preferably all, of said cavities are ducts may have a first end thermally connected to said heat source and a second end thermally connected to said heat sink.

Preferably, at least some of said cavities are in fluid connection with adjacent cavities and together constitute a hermetically sealed fluid-filled chamber. This is a

precondition to or at least further helps to achieve a uniform radiator surface temperature.

Preferably, said plurality of support elements are tube portions. Such tube portions are easily provided with appropriate lengths and can easily be connected, for instance by welding, to form the heating support according to the invention. In the heating support, the tube portions may have circular, oval or rectangular cross sections. Such cross sections allow the condensed fluid (liquid) to easily flow back from a heat sink to the heat source.

Preferably, said tube portions are arranged next to each other with their first ends in fluid connection with each other through a connecting duct. Such tube portions are dead-end ducts and their first ends may all be in thermal contact with the heat source while their second ends form separate heat sinks. In addition, the arrangement of the tube portions next to each other provides ample support for objects to be placed on heating support in order to be heated and dried, if wet.

Alternatively, at least some of the first ends are in fluid connection with each other through a first connecting duct and/or at least some of the second ends are in fluid connection with each other through a second connecting duct.

The portions may be shaped as straight tube portions extending away from said connecting duct.

In a first preferred version, the tube portions extend in parallel to each other. In this way, they may form a comb-like rack which is suitable for placing objects to be heated and dried, if wet.

In a second preferred version, the tube portions are tube portions extending in a non parallel fashion to each other. In that way, they may form a tree-like or cactus-like support where objects such as clothing to be heated and dried, if wet, can be suspended.

Preferably, the hermetically sealed cavity comprises a wick-like element

wettable/impregnable by said fluid and extending from said at least one heat sink to said at least one heat source. This allows condensed fluid (liquid) to easily flow back from the heat sink to the heat source by capillary action.

As an alternative or in addition to the wick-like element, said hermetically sealed fluid- filled cavity is shaped such that the heating support has at least one set-up or mounting position where said heat source is at a lower location than said heat sink. This allows condensed fluid (liquid) to easily flow back from a heat sink to the heat source by the action of gravity when the heating support is in said at least one set-up or mounting position. Preferably, the heating support comprises at least one fixing means for fixing the heating support to a wall, bottom or ceiling of a room or a closet.

Preferably, the fixing means allows the heating support to be fixed in at least two mounting positions. A first mounting position or operating position may be a horizontal or almost horizontal position of a plate-like, grid-like or comb-like heating support providing a large support area for objects to be placed thereon. A second mounting position or non-operating position may be a vertical or almost vertical position of the same plate-like, grid-like or comb-like heating support when it is not needed and the space is used for a purpose other than heating and drying clothing.

Preferably, the heat source is an electric heating element. It may be a point-like heat source extending around a point within the heating support or it may be a line-shaped heat source extending along a line within the heating support. Preferably, the location and extension of the heat source coincides with the location and extension of a liquid sump for receiving condensed fluid. This guarantees that enough condensed fluid is always present in good thermal contact with the heat source.

Preferably, the ratio of the fluid volume, measured with all of the liquid in its liquid form, to the volume of the hermetically sealed fluid-filled cavity is comprised between 1/100 and 1/5.

Preferably, the inner surface of said hermetically sealed fluid-filled cavity is coated with a sintered material having a grain size of less than 0.3 mm, preferably less than 0.1 mm.

The fluid may be water or a mixture of water with some additives. One type of additive may be a surfactant for reducing the surface tension of the condensed fluid. Another type of additive may be a nucleating agent for helping to start bubble formation with the fluid.

The heating support according to the invention may be manufactured by

- providing a plurality of support elements arranged next to each other and together providing a support base for objects to be placed thereon, wherein at least some, preferably all, of said support elements comprise a cavity,

- thermally connecting a first cavity portion to at least one heat source,

- thermally connecting a second cavity portion to at least one heat sink, - filling said cavity or cavities with a fluid, and

- hermetically sealing said cavity or cavities.

Preferably, before hermetically sealing said cavity or cavities, they are evacuated. Preferably, evacuation means removing air molecules such as N2, O2 and CO2 from said cavity or cavities.

Preferably, said evacuation is performed by alternate pumping and non-pumping periods, said non-pumping periods allowing time for volatiles dissolved in the liquid phase of the fluid to escape into the gas phase (steam) of the fluid.

Preferably, said evacuation is performed by heating and evaporating the fluid and using the gas phase (steam) of the fluid to displace molecules such as N2, O2 and CO2 from said cavity or cavities.

The heating support according to the invention may be operated by intermittently evaporating said fluid in said first cavity portion at a temperature provided by said heat source and condensing said fluid in said second cavity portion at a temperature provided by said heat sink.

The invention also provides a heating closet, comprising a heating support as defined in the preceding paragraphs.

Preferably, the heating closet comprises a ventilation unit which can be switched between an internal circulation mode for circulating air within the heating closet and an external circulation mode for circulating air into, through and out of the heating closet. This allows objects to be efficiently heated or dried when placed in the heating closet according to the invention.

Preferably, the heating closet comprises a humidity sensor for sensing the relative humidity of the air within the heating closet and connected to the ventilation unit, wherein the ventilation unit can be switched between the internal circulation mode and the external circulation mode as a function of relative humidity within the heating closet. This allows alternate drying of the objects and venting the air in the closed for optimized drying results.

Preferably, the heating closet comprises a temperature sensor for sensing the temperature of the air within the heating closet and connected to the heat source, wherein the heat source can be switched between a first heating mode providing a first heating power and a second heating mode providing a second heating power as a function of temperature within the heating closet. Preferably, the first heating power is a maximum heating power and said second heating power is a minimum or zero heating power.

Further objects, advantages and applications of the heating support and heating closet according to the invention will be apparent from the description of the drawings which are purely exemplary and not to be construed to limit the scope of the present invention, wherein:

Fig. 1 is a front view of a heating support according to a first embodiment of the invention (flat radiator with a bend in the middle half-way along its maximum dimension radiator main axis) in a use position;

Fig. 2 is a top view of the heating support according to the first embodiment of the invention in the use position;

Fig. 3 is a side view of the heating support according to the first embodiment of the invention in the use position;

Fig. 4 is a side view of the heating support according to the first embodiment of the invention in a non-use position;

Fig. 5 is a front view of two heating supports according to the first embodiment of the invention, with each of them in the use position and arranged next to each other at different heights;

Fig. 6 is a planar cross section along a plane parallel to the drawing plane of

Fig. 1 or Fig. 5 of a portion (heat source) of the heating support according to the first embodiment of the invention;

Fig. 7 is a front view of a heating support according to a second embodiment of the invention (flat radiator without a bend in the middle half-way along its maximum dimension radiator main axis / flat radiator with straight linear heat source and liquid sump) in a use position;

Fig. 8 is a perspective view of a first arrangement of a plurality of heating

supports according to the invention; Fig. 9 is a perspective view of a second arrangement of a plurality of heating supports according to the invention;

Fig. 10 is a perspective view of a third arrangement of a plurality of heating

supports according to the invention;

Fig. 1 1 is a front view of a fourth arrangement of a plurality of heating supports according to the invention;

Fig. 12 is a side view of a fifth arrangement, similar to Figs. 1 , 2, 3 and 4, of a heating support according to the invention;

Fig. 13 is a front view of a sixth arrangement, similar to Fig. 10, of a heating support according to the invention;

Fig. 14 is a front view of a heating support according to a third embodiment of the invention (stand-alone tree-like radiator) in a use position.

Fig. 15 is a top view of the heating support according to the third embodiment of the invention in the use position; and

Fig. 16 is a perspective view of the heating support according to the third

embodiment of the invention in the use position.

Referring to Fig. 1 , a front view of a heating support 1 according to a first

embodiment of the invention is shown. The heating support 1 is an approximately flat, comb-like radiator with a slight bend in the middle half-way along its maximum dimension radiator main axis. The heating support 1 is shown in a use position where objects to be heated can be placed on it. The heating support 1 has an electric heat source 2 located in the region of the slight bend in the middle of its main axis or along its largest dimension. Also shown is an electric cable 41 having a mains plug 42 at its first end and a heater plug 43 at its second end. The heating support 1 is hermetically sealed and filled with a fluid. A first portion of its inner volume is filled with a liquid (condensed vapor) and a second portion of its inner volume is filled with steam/vapor (evaporated liquid). The liquid and vapor portions of the fluid within the heating support are in thermodynamic equilibrium, with the mass ratio of the vapor portion to the liquid portion being a function of temperature or the partial pressure of the vapor being a function of temperature. The entire surface of the heating support 1 except for its region in immediate thermal contact with the heat source 2 constitutes a heat sink 3, i.e. a distributed heat sink, where heat from within the heating support 1 is transferred, by convection, radiation and heat conduction, to the air-filled space surrounding the heating support 1. As a result, objects H1 , H2, H3, H4, H5, H6, H7 or H8 placed on the heating support 1 , as shown in Figs. 8, 9 and 10, will be heated.

Referring to Fig. 2, a top view of the heating support 1 according to the first embodiment of the invention and in its use position is shown. The heating support 1 and the distributed heat sink 3 comprises a duct or duct system 5 having first ends 5a in fluid contact and in thermal contact with the heat source 2 and second ends 5b forming dead ends of the duct or duct system 5. As a result, steam/vapor formed by evaporating liquid in the region of the heat source 2 can be easily distributed within the heating support 1 by thermal action and contributes to a uniform temperature distribution within the heating support 1 and at the outer surface of the heating support 1 , thus forming a radiator surface having a uniform temperature distribution.

In its use position, the region of the heat source 2 of the heating support 1 is at a lowest position. As a result, liquid formed by condensing steam/vapor in the region of the distributed heat sink 3 can easily flow back from the distributed heat sink 3 of the heating support 1 to the heat source 2 of the heating support 1 by the action of gravity. The duct or duct system 5 of the heating support 1 provides a plurality of support elements arranged next to each other in a comb-like fashion and together providing a support base for objects to be placed on the heating element 1.

Referring to Fig. 3, a side view of the heating support 1 according to the first embodiment of the invention is shown in its use position. In this use position, all the duct ends 5b, best shown in Fig. 2, are at a slightly higher position, barely

recognizable in Fig. 3, than the duct ends 5a. This improves liquid backflow form the distributed heat sink 3 to the localized heat source 2 of the heating support 1. Also shown is a chain 44 in its extended/stretched position with its first end fixed to the heating support 1 and its second end fixed to a wall mount 45. Preferably, a first chain 44 and a first wall mount 45 are located at the first lateral end (left-side end in Fig. 2) of the heating support 1 and a second chain 44 and a second wall mount 45 are located at the second lateral end (right-side end in Fig. 2) of the heating support 1 . Referring to Fig. 4, a side view of the heating support 1 according to the first embodiment of the invention is shown in a non-use position. In this non-use position, all the duct ends 5b, best shown in Fig. 2, are at their highest position much higher than the duct ends 5a. Thus, even after the heating support 1 having been used in its use-position, liquid backflow form the distributed heat sink 3 to the localized heat source 2 of the heating support 1 is possible. Also shown is the chain 44 in its non- extended/slack position and the wall mount 45.

Referring to Fig. 5, a front view of two heating supports 1 according to the first embodiment of the invention is shown, with each of them in the use position and arranged next to each other at different heights. Each of the two heating supports 1 is fixed to a wall with a first wall mount 45 at the left-side end of the heating support 1 and with a second wall mount 45 at the right-side end of the heating support 1. Unlike the chain-mounted heating support 1 hinged to the wall mounts 45, as shown in Figs. 3 and 4, the two heating supports 1 shown in Fig. 5 are rigidly fixed to the wall mounts 45 with a slight slope between the duct ends 5b and the ducts ends 5a, i.e. permanently in the use-position.

Referring to Fig. 6, a planar cross section along a plane parallel to the drawing plane of Fig. 1 or Fig. 5 of a portion of the heat source 2 of the heating support 1 according to the first embodiment of the invention is shown. The localized heat source 2 and a portion of the distributed heat sink 3 is shown. The distributed heat sink 3 is formed by the duct or duct system 5 of the heating support 1. Also shown is a portion of the duct or duct system 5 with its first ends 5a in fluid contact and in thermal contact with the heat source 2. The second ends 5b, best seen in Fig. 2 and forming dead ends of the duct or duct system 5, are not visible in the cross sectional view of Fig. 6. The localized heat source 2 is in thermal contact with a first chamber C1 of the heating support 1 and second chambers C2 of the heating support 1 are in thermal contact with the distributed heat sink 3.

The heat source 2 comprises an electric heater cartridge 1 1 extending into a liquid sump filled with liquid (condensed fluid) of the first chamber C1 , as well as an electric connection unit 12 and a control unit 13 connected to the electric heater cartridge 11 for adjusting electric power fed into the liquid sump of the heat source 2. Due to the inclination of the duct or duct system 5, virtually all of the liquid L condensed from the steam/vapor S in the second chambers C2 of the distributed heat sink 3 flows back to the liquid sump in the first chamber C1. The liquid level in the liquid sump is defined by the liquid/steam interface LSI. By increasing or decreasing the electric power input of the electric cartridge 1 1 , the uniform temperature of the heating support 1 can be increased or decreased with a corresponding increase or decrease in vapor pressure and a corresponding decrease and increase in the liquid level.

Referring to Fig. 7, a front view of a heating support 1’ according to a second

embodiment of the invention is shown. The heating support 1’ is flat radiator with a straight linear heat source 2’ and liquid sump, i.e. a radiator without a bend in the middle half-way along its maximum dimension radiator main axis and having a less localized heat source 2’ and less localized heat sump. Both the heat source 2’ and the liquid sump extend along the entire length of the radiator along its maximum dimension main axis. The top view of the second embodiment (not shown) looks very similar to the top view of the first embodiment (Fig. 2). As in the first embodiment, the distributed heat sink 3’ of the second embodiment is constituted by the duct or duct system 5. In the use position of the second embodiment, all the duct ends 5b, best shown in Fig. 2, are at a slightly higher position, barely recognizable in Fig. 3, than the duct ends 5a. Again, this improves liquid backflow form the distributed heat sink 3’ to the localized heat source 2’ of the heating support 1 \

The heat source 2’ comprises an elongate (oblong) electric heater membrane 21 extending along the entire length of the heating support 1’ and attached to the outer surface of the heating support 1’ in thermal contact with an elongate (oblong) first chamber (not shown), as well as an electric connection unit 22 and a control unit 23 connected to the electric heater membrane 21 for adjusting electric power fed into the liquid sump of the heat source 2’.

Referring to Fig. 8, a perspective view of a first arrangement of a plurality of heating supports 1 according to the invention is shown. On a upper heating support 1 , a group of first types of objects H1 , H2, H3 (e.g. hats, gloves and shawls) to be heated can be placed. On a lower heating support 1 , a group of second types of objects H8 (e.g. shoes and boots) to be heated can be placed.

Referring to Fig. 9, a perspective view of a second arrangement of a plurality of heating supports 1 according to the invention is shown. On a upper heating support 1 , a group of third types of objects H4 (e.g. towels) to be heated can be placed. On a lower heating support 1 , a group of fourth types of objects H5 and H6 (e.g. sweaters and socks) to be heated can be placed.

Referring to Fig. 10, a perspective view of a third arrangement of a plurality of heating supports 1 according to the invention is shown. On a uppermost heating support 1 , a group of third types of objects H4 (e.g. towels) to be heated can be placed. On a lower heating support 1 , a group of fifth types of objects H7 (e.g. shirts and socks) to be heated can be placed. On a lowermost heating support 1 , a group of fifth types of objects H7 (e.g. shirts) to be heated can be placed. Unlike the first and second arrangements shown in Figs. 8 and 9, this third arrangement comprises a partially cut away heating closet 4 including three heating supports 1 at different levels and an air duct 46 for evacuating the closet 4.

When heated, the steam/vapor within the heating support 1 or 1’ spreads rapidly and has the same temperature throughout the inner chamber(s) C2 of the heating support 1 or 1 \ As a result, a very high thermal conductivity between any two different locations of the heating support according to the invention is achieved, thus preventing any localized temperature peaks even if the heating support is loaded with densely-packed objects to be heated.

Referring to Fig. 11 , a front view of a fourth arrangement of a plurality of heating supports according to the invention is shown. This fourth arrangement is similar to the third arrangement shown in Fig. 10. Also shown is an air duct 46 cooperating with a fan/ventilator 47 for air flow adjustment.

Referring to Fig. 12, a side view of a fifth arrangement, similar to Figs. 1 , 2, 3 and 4, of a heating support 1 according to the invention is shown. This fifth arrangement includes an air duct 46 for evacuating a closet 4 (not shown).

Referring to Fig. 13, a front view of a sixth arrangement, similar to Fig. 10, of a heating support 1 according to the invention is shown. Also shown are an air duct 46 and a fan/ventilator 47, as in Fig.1 1 , as well as a switching unit 48 for air flow adjustment within a heating closet 4. Due to the switching unit 48, ventilation of the closet 4 can be switched between an internal circulation mode for circulating air within the heating closet 4 and an external circulation mode for circulating air into, through and out of the heating closet 4. This allows objects to be efficiently heated or dried when placed in the heating closet 4 according to the invention. Referring to Fig. 14, a front view of a heating support 1” according to a third

embodiment of the invention is shown. The heating support 1” is a stand-alone tree like radiator with a heat source 2” in its bottom part and a duct or duct system 5 extending upwardly from the heat source 2” in the bottom part. The heating support 1” also comprises a distributed heat sink 3 formed by a duct or duct system 5 having first ends 5a in fluid contact and in thermal contact with the heat source 2” and second ends 5b forming dead ends of the duct or duct system 5. As a result, steam/vapor formed by evaporating liquid in the region of the heat source 2” can be easily distributed within the heating support 1” by thermal action and contributes to a uniform temperature distribution within the heating support 1” and at the outer surface of the heating support 1”, thus forming a radiator surface having a uniform temperature distribution. As a result, liquid formed by condensing steam/vapor in the region of the distributed heat sink 3” can easily flow back from the distributed heat sink 3” of the heating support 1” to the heat source 2” of the heating support 1” by the action of gravity.

Referring to Fig. 15, a top view of the heating support 1” according to the third embodiment of the invention is shown.

Referring to Fig. 16, a perspective view of the heating support 1” according to the third embodiment of the invention is shown.

List of reference signs

1 heating support

1’ heating support

1” heating support

2 heat source

2’ heat source

2” heat source

3 heat sink

3’ heat sink

3” heat sink

4 heating closet

5 duct

5a first end (of duct)

5b second end (of duct)

1 1 electric heater (cartridge)

12 electric connections

13 control unit

21 electric heater (membrane)

22 electric connections

23 control unit

C1 first chamber

C2 second chamber

L liquid (water)

S steam (water vapor)

LSI liquid/steam interface (water level)

41 electric cable

42 mains plug

43 heater plug

44 chain 45 wall mount

46 air duct

47 fan (for air flow adjustment)

48 switching unit (for air flow adjustment)

H1 object (to be heated)

H2 object (to be heated)

H3 object (to be heated)

H4 object (to be heated)

H5 object (to be heated)

H6 object (to be heated)

H7 object (to be heated)

H8 object (to be heated)