Electric radiator with heat transfer fluid and associated method for filling the radiator with heat transfer fluid

Abstract

The present invention relates to an electric radiator (1) with heat transfer fluid, comprising a collector assembly (2a, 2b), several blades (3, 3a) mounted spaced from each other, a heating element (5) mounted in the collector assembly (2a, 2b) and configured to heat the heat transfer fluid (7), the lower blade (3a) in the use position of the radiator (1) being in fluid communication with the collector assembly (2a, 2b) by a single hole (6a) formed in the lower part of the lower blade (3a).

Description

[0001] The invention relates to the field of heating, and more particularly relates to an electric radiator with heat transfer fluid and to an associated method of filling the radiator with heat transfer fluid.

[0002] Electric radiators with heat transfer fluid can take several forms. In particular, towel dryers are known, comprising one or two parallel collectors on which are attached blades, also generally parallel, fixed to the collector or to the two collectors by electric welding. The blades are hollow and the collector or collectors are hollow, and holes are formed to put the interior of the blades in fluid communication with the interior of the one or two collectors to form an internal space for circulation of heat transfer fluid, allowing the heat transfer fluid, when heated by an immersion heater type heating element housed in one of the two collectors, to circulate in this internal space throughout the towel dryer, circulating by convection in the blades and the collector or collectors.

[0003] In current blade-type towel dryers as described above, the space inside the towel dryer, formed by the inside of the blades in communication with the inside of the collectors, and in which the heat transfer fluid circulates, cannot be completely filled with the heat transfer fluid. Indeed, it is necessary to keep a space available to allow the heat transfer fluid to expand when it is hot. Since the radiator in use is sealed to prevent any leakage of heat transfer fluid, this means that when the internal space of the radiator is filled with heat transfer fluid, it is necessary to keep an air space. This air space will then remain permanently in the radiator, changing volume with the change in volume of the heat transfer fluid with the temperature.

[0004] In the normal operating position of a conventional radiator according to the state of the art, namely vertical, the heat transfer fluid, which is denser than air, will tend to occupy the lower part of the radiator, while the air will be trapped in the upper part of the radiator.

[0005] The consequence is that the lower part of the radiator, filled with heated heat transfer fluid, will be much hotter than its upper part, which is mostly filled with air. The surface temperature distribution of the towel dryer is therefore not uniform, with the upper blades being colder than the others and the lower blades being too hot.

[0006] This situation is not satisfactory, because the hot lower part is likely to be touched by young children who then risk being burned, while the towels, most often placed in the upper part, are not heated or not dried optimally.

[0007] The present invention aims to overcome the drawbacks of the prior art.

[0008] EP2034264B1 and EP2072168B1 describe the state of the art of the invention.

[0009] The present invention therefore relates to an electric radiator with heat transfer fluid, comprising a collector assembly having a longitudinal direction, the collector assembly being sealed, several blades mounted spaced apart from each other along the longitudinal direction of the collector assembly, the blades being hollow and in fluid communication with the collector assembly to form an interior volume for circulation of the heat transfer fluid configured to contain the heat transfer fluid and air to support the variations in volume of the heat transfer fluid with the temperature in the interior volume, a heating element mounted in the collector assembly and configured to heat the heat transfer fluid in the interior volume, the heating element being configured to be powered by an electrical power supply,characterized by the fact that the lower blade in the radiator's operating position is in fluid communication with the collector assembly via a single hole formed in the lower part of the lower blade, such that the lower blade, in the radiator's operating position in which the heat transfer fluid fills the part of the collector assembly where the fluid communication hole with the lower blade is formed, is configured to comprise heat transfer fluid up to the level of the hole and air trapped above.,

[0010] Thus, by filling the radiator adequately, it is possible to trap the air necessary for the variations in the volume of the heat transfer fluid not in the upper part, but in the lower blade: filling with heat transfer fluid will seal the fluid communication hole between the lower blade and the collector assembly and trap the air in the lower blade. The heat transfer fluid will thus always expand with the volume of air trapped in the lower blade, which guarantees that the hole will always be sealed, and allows the temperature of the lower blade to be lowered, thus reducing the risk of burns by contact in the lower part of the towel dryer.

[0011] In addition, more heat transfer fluid will be located, at a constant internal space volume, in the upper part of the radiator, which guarantees better heating in the upper part. This results in a better distribution of the surface temperature of the radiator, with a constant temperature in the central part of the radiator for a given temperature of the heat transfer fluid, a movement of heat from the lower part of the radiator to the upper part of the radiator, thanks to the distribution of air and heat transfer fluid trapped in the lower blade instead of the upper part in the state of the art, which makes it possible to reduce the size of the radiator because more surfaces can be heated compared to existing radiators.

[0012] The term “blade” means any heating element, regardless of its shape, in which a heat transfer fluid can circulate. Most often, the blade will have a flattened rectangular parallelepiped shape, but other shapes can of course be envisaged within the framework of the present invention, for example a tubular shape or other shapes conventionally encountered for radiators and other towel dryers.

[0013] The single fluid communication hole formed between the lower blade and the collector assembly also makes it possible to limit fluid exchanges between the lower blade and the collector assembly, and in particular to limit the passage of air trapped in the lower blade towards the collector assembly, throughout the life of the radiator, and in particular if the latter is moved or transported. The fact that the level of heat transfer fluid in the collector assembly is above this single fluid communication hole guarantees the sealing of the hole with respect to the passage of air trapped in the lower blade above the hole towards the collector assembly.

[0014] According to one embodiment, the blade immediately above the lower blade in the radiator use position is also in fluid communication with the collector assembly by a single hole formed in the lower part of the blade, such that the blade, in the radiator use position in which the heat transfer fluid fills the part of the collector assembly where the fluid communication hole with the lower blade and the blade immediately above is formed, is configured to comprise heat transfer fluid up to the level of the hole and air trapped above. The movement of heat towards the upper part of the radiator is thus increased since two volumes of air trapped in the two lower blades make it possible to accommodate the changes in volume of the heated heat transfer fluid.

[0015] The volume of air required for the variations in the volume of the heat transfer fluid can thus be distributed over several lower blades, for example the two lower blades, in order to reduce the temperature in the lower part of the radiator. Depending on the design of the radiator, the person skilled in the art will be able to determine the number of blades which must only communicate through a hole with the collector assembly.

[0016] According to one embodiment, the manifold assembly comprises a manifold configured to be vertical in the radiator use position.

[0017] According to one embodiment, the collector assembly comprises two parallel collectors configured to be vertical in the radiator's operating position. In the case where the collector assembly comprises two vertical collectors, these are generally at each end of the blades. The lower blade, and where appropriate the immediately upper blade, then only communicate fluidically with a single collector.

[0018] According to one embodiment, the fluid communication hole of the lower blade, and where appropriate of the blade immediately above in the position of use of the radiator, are formed below half the height of the corresponding blade, preferably below one third of the height of the corresponding blade. The volume of trapped air will then correspond to half or two thirds of the volume of the blade, the remainder being occupied by the heat transfer fluid.

[0019] According to one embodiment, the diameter of the fluid communication hole of the lower blade, and where appropriate of the blade immediately above in the position of use of the radiator, is less than 8 mm, preferably between 5 and 7.5 mm, more preferably between 5.5 and 7 mm.

[0020] The other blades of the radiator, above the lower blade in the position of use of the radiator, and if necessary the blade immediately above, communicate with the collector assembly by several separate holes, preferably four holes, or by a single, larger hole, allowing the blade to be filled with a maximum of heat transfer fluid and a minimum of air, and also allowing good circulation of the heat transfer fluid in the interior volume of the radiator. A homogeneity of surface temperature is thus obtained by better circulation of the heat transfer fluid by convection in the interior volume of the radiator.

[0021] According to one embodiment, the heating element is of the immersion heater type.

[0022] According to one embodiment, the collector assembly has a tightly closable opening at a lower end in the radiator's operating position for filling the heat transfer fluid inside the radiator, optionally configured to be closed by the heating element.

[0023] The invention also relates to a method for filling a heat transfer fluid radiator with heat transfer fluid as described above, characterized in that it comprises: placing the interior volume of the radiator under vacuum through an opening in the collector assembly, introducing a heat transfer fluid through the same opening, suspending the filling of the heat transfer fluid to break the vacuum and allow air to enter the interior volume of the radiator, and continuing to fill the interior volume of the radiator with heat transfer fluid until it is completely filled.

[0024] According to one embodiment, for a radiator in which the heat transfer fluid introduction opening is formed in the lower part in the use position of the radiator, the filling is carried out with the radiator inclined, with its lower end facing upwards. It is thus possible to ensure that the heat transfer fluid will be mostly in the upper part of the radiator (at the bottom when the radiator is inclined during filling) while the air will be trapped in the lower part (at the top when the radiator is inclined during filling). Once the radiator is tightly closed and then turned over, the air will remain trapped at the bottom in the vertical use position.

[0025] According to one embodiment, the filling opening is sealed by the heating element after filling.

[0026] In order to better illustrate the object of the present invention, a preferred embodiment will now be described, in conjunction with the accompanying drawings.

[0027] On these drawings: [ Fig. 1 ] is a front view of a radiator according to one embodiment of the invention. [ Fig. 2 ] is a sectional view along AA' of the radiator of the Figure 1 . [ Fig. 2a ] is a detail view of the detail of the Figure 2 . [ Fig. 3 ] is a schematic view of a radiator according to the present invention being filled by the method of the present invention. [ Fig. 4a ] is a schematic view of a radiator filled by the method of the present invention, at the end of filling in an inclined position. [ Fig. 4b ] is a schematic view of a radiator filled by the method of the present invention, at the end of filling in the position of use.

[0028] If we refer to the Figures 1, 2 And 2a, we can see that a radiator 1 according to the invention has been shown.

[0029] The radiator 1 is of the towel dryer type, and comprises two collectors 2a, 2b (forming a collector assembly) on which blades 3, 3a are mounted.

[0030] The collectors 2a, 2b are tubular in the non-limiting example shown, and sealed at each end. Although the collectors 2a, 2b have been shown at each end of the blades 3, 3a, it is also conceivable that the collectors 2a, 2b are located at the same end of the blades 3, 3a, without departing from the scope of the present invention, or even that there is only one collector of larger volume forming the collector assembly in which the heat transfer fluid circulates, from which the blades 3, 3a extend cantilevered.

[0031] The blades 3a, 3a are of rectangular parallelepiped shape in the non-limiting example shown, generally flat, but could take other shapes (tubular, etc.) without departing from the scope of the present invention.

[0032] The blades 3, 3a are hollow, as are the collectors 2a, 2b, the interior of the collectors 2a, 2b communicating with the interior of the blades 3, 3a to form in the radiator 1 an interior volume into which a heat transfer fluid is introduced, for example of the propylene glycol type, without the invention being limited in this respect. The heat transfer fluid could thus for example be an oil or other.

[0033] An electric heating element 5, of the immersion heater type, is introduced into the lower end of one of the collectors 2a, 2b, to heat the heat transfer fluid. The lower end 5a of the electric heating element 5 constitutes a sealed plug for the end of the collector 2a, 2b into which it is introduced.

[0034] A human-machine interface 4, conventionally comprising a screen and buttons, makes it possible to control the heating of the electric heating element 5, and to program the heating of the radiator 1. The human-machine interface 4 comprises the electronic components necessary to control the electric heating element 5: an electronic control circuit (of the microprocessor, microcontroller, processor, programmable gate array (FPGA), application-specific electronic component (ASIC), digital signal processor (DSP) type, associated with internal or external memory of the component), and possibly electronic remote communication components of the infrared receiver, Wifi ®<, Sigfox ®<, Bluetooth ®<, Lora ®< or equivalent type transmitter / receiver making it possible to remotely control the human-machine interface 4.The person skilled in the art will be able to program in the electronic components of the human-machine interface 4 the algorithms necessary to control the electric heating element 5, communicate remotely with an external control unit (remote control, home automation system, remote server, etc.) and more generally program the operation of the radiator 1.

[0035] The radiator 1 is powered by mains current via a power cord A providing sufficient power for the electric heating element 5. The human-machine interface 4 can be powered by battery or by the same power supply as the electric heating element 5, by means of a transformer (not shown) integrated into the radiator 1. As can be seen in the detail of the Figure 1, the blades 3 communicate with each collector 2a, 2b via several holes 6, four in the example shown, this with the aim of facilitating the circulation of the heat transfer fluid in the radiator 1 in order to distribute the heat well in the radiator 1, the heat transfer fluid circulating in the interior volume of the radiator 1 according to its temperature. The holes 6 can have diameters of the order of 8 mm, and can be aligned or on different lines. The blades 3 could also communicate with each collector 2a, 2b via fewer holes, or even via a single hole of larger surface area, representing for example the total surface area of ​​the four holes, the hole(s) formed between the blades 3 and the collectors 2a, 2b having to allow optimal fluid communication between the interior volume of the blade considered and the collectors 2a, 2b.Unlike the lower blade 3a, the hole(s) formed for the blades 3 must connect both the upper part and the lower part of the blade in question, to minimize the volume of air trapped in each blade 3.

[0036] The holes 6 can have any shape (round, square, oblong, etc.), the objective of the holes 6 of the blades 3 being to allow maximum fluid exchange between the blades 2 and the collectors 2a, 2b, while guaranteeing good fixing of the blades 3 to the collectors 2a, 2b.

[0037] The lower blade 3a has the same general shape as the other blades 3, but communicates with the collectors 2a, 2b only through a single hole 6a, shown in Figure 2a . Thus, the fluid exchanges between the collectors 2a, 2b and the lower blade 3a are more limited than for the other blades 3.

[0038] The lower blade 3a communicates with only one of the two collectors 2a, 2b through a hole 6a.

[0039] The diameter of the hole 6a is less than 8 mm, preferably between 5 and 7.5 mm, more preferably between 5.5 and 7 mm.

[0040] The hole 6a is preferably formed in the lower part of the lower blade 3a, preferably in the lower third of the lower part of the lower blade 3a, in the vertical use position of the radiator 1.

[0041] The collectors 2a, 2b and the blades 3, 3a are metallic, to provide good thermal inertia, the blades 3, 3a being fixed to the collectors 2a, 2b for example by electric welding.

[0042] It should be noted that, as indicated above, although the radiator 1 has been described as having two collectors 2a, 2b, it is also conceivable that a radiator according to the invention has only one collector, sufficiently large to allow circulation of heat transfer fluid in the radiator. The lower blade would however also have a single communication hole with this single collector.

[0043] Similarly, it could be envisaged, without departing from the scope of the present invention, that several lower blades, for example the three lowest blades or the two lowest blades in the vertical position of use of the radiator, communicate with the collector(s) only by a single hole 6a, in a manner analogous to the blade 3a shown in the example of Figures 1, 2 And 2a , in order to limit fluid exchanges in the lower part of the radiator 1.

[0044] If we now refer to the Figure 3, we can see that a radiator 1 according to the invention has been shown during its filling with heat transfer fluid, before its use.

[0045] As we can see on this Figure 3 , the radiator 1 is placed on an inclined plane 10, supported by legs 11, with the lower side of the radiator 1 in use in a high position on the inclined plane 10, the blades 3 resting on the inclined plane 10 for greater stability.

[0046] A heat transfer fluid distribution device (not shown) supplies heat transfer fluid to the radiator 1 by means of a cord 12 ending in a connector 13 connected in a sealed manner to the lower end of the collector 2b.

[0047] To fill the radiator 1 with heat transfer fluid, the internal volume of the radiator 1 is first evacuated through an opening in the collector 2b, the connector 13 is connected and the heat transfer fluid is supplied through the same opening, then the filling of the heat transfer fluid is suspended to break the vacuum and allow air to enter the internal volume of the radiator 1, and the filling of the internal volume of the radiator 1 with heat transfer fluid is continued until it is completely filled, while leaving a volume of air in the internal volume of the radiator 1 to accommodate variations in the volume of the heat transfer fluid with temperature.

[0048] We obtain a filling of the radiator 1 as shown in Figures 4a And 4b , where only the lower part of radiator 1 in use has been shown. The Figure 4a represents radiator 1 in the intermediate position while the Figure 4brepresents radiator 1 in the vertical, operating position.

[0049] For the lower blade 3a, the single hole 6a, closed by the heat transfer fluid 7, traps a volume of air 8 above the hole.

[0050] For the upper blades 3, given that the hole(s) provide access to a larger volume of the blade 3 in question, while allowing better circulation of the heat transfer fluid 7, the blade 3 has, at constant volume compared to the blade 3a, a larger volume of heat transfer fluid 7 and a much smaller volume of air 8. Table 1 below shows the temperature distribution for a radiator according to the prior art, where all the blades have the same fluid communication with the collector assembly, and for a radiator according to the invention, where one or two lower blades have fluid communication with the collector assembly constituted by a single hole.

[0051] The temperature measurement points correspond to different heights of the radiator in the vertical operating position, with the value of the measurement points increasing with the downward direction, measurement point 1 representing the highest position in the vertical operating position of the radiator, measurement point 21 representing the lowest position in the vertical operating position of the radiator. [Table 1] Temperature measuring point State-of-the-art radiator (Temperature in °C) Radiator according to the invention (Temperature in °C) Temperature difference 1 35 43,4 8,4 2 40,9 45,6 4,7 3 52,7 53,6 0,9 4 43,4 68,7 25,3 5 52,6 71,3 18,7 6 69,9 74,1 4,2 7 73,8 73,5 -0,3 8 75,6 74,3 -1,3 9 77,9 76,4 -1,5 10 71,1 70,8 -0,3 11 72 71,9 -0,1 12 73,3 73,3 0 13 70,3 70,2 -0,1 14 71,6 71,4 -0,2 15 73,9 72,9 -1 16 67,6 67,4 -0,2 17 68,9 67,9 -1 18 72,2 71 -1,2 19 48 32,3 -15,7 20 49,7 33,9 -15,8 21 54,5 40,2 -14,3

[0052] It can be seen from this comparison that in the central part of the radiator, the temperatures remain substantially identical, while the temperatures increase significantly in the upper part of the radiator according to the invention, and decrease significantly in the lower part, reaching in particular temperatures not likely to cause burns, unlike the temperatures observed with the radiator of the state of the art.

Claims

1. - Electric radiator (1) with heat transfer fluid (7), comprising a collector assembly (2a, 2b) having a longitudinal direction, the collector assembly (2a, 2b) being sealed, several blades (3, 3a) mounted spaced apart from each other along the longitudinal direction of the collector assembly (2a, 2b), the blades (3, 3a) being hollow and in fluid communication with the collector assembly (2a, 2b) to form an interior volume for circulation of the heat transfer fluid (7) configured to enclose the heat transfer fluid (7) and air (8) to support the variations in volume of the heat transfer fluid (7) with the temperature in the interior volume, a heating element (5) mounted in the collector assembly (2a, 2b) and configured to heat the heat transfer fluid (7) in the interior volume, the heating element (5) being configured to be powered by an electrical power supply (A), characterized by the fact thatthe lower blade (3a) in the position of use of the radiator (1) is in fluid communication with the collector assembly (2a, 2b) only by a hole (6a) formed in the lower part of the lower blade (3a), and the radiator (1) is configured such that the lower blade (3a), in the position of use of the radiator (1) in which the heat transfer fluid (7) fills the part of the collector assembly (2a, 2b) where the fluid communication hole (6a) with the lower blade (3a) is formed, comprises heat transfer fluid (7) up to the level of the hole (6a) and air (8) trapped above.

2. - Electric radiator (1) with heat transfer fluid according to claim 1, characterized by the fact thatthe blade immediately above the lower blade (3a) in the position of use of the radiator (1) is also in fluid communication with the collector assembly (2a, 2b) by a single hole formed in the lower part of the blade, such that the blade, in the position of use of the radiator (1) in which the heat transfer fluid (7) fills the part of the collector assembly (2a, 2b) where the hole for fluid communication with the lower blade (3a) and the blade immediately above is formed, is configured to comprise heat transfer fluid (7) up to the level of the hole and air (8) trapped above.

3. - Electric radiator (1) with heat transfer fluid according to claim 1 or claim 2, characterized by the fact that the collector assembly (2a, 2b) comprises a collector configured to be vertical in the position of use of the radiator (1).

4. - Electric radiator (1) with heat transfer fluid according to claim 1 or claim 2, characterized by the fact thatthe collector assembly (2a, 2b) comprises two parallel collectors (2a, 2b) configured to be vertical in the position of use of the radiator (1).

5. - Electric radiator (1) with heat transfer fluid according to one of claims 1 to 4, characterized by the fact that the fluid communication hole (6a) of the lower blade (3a), and where appropriate of the blade immediately above in the position of use of the radiator (1), are formed below half the height of the corresponding blade (3a), preferably below a third of the height of the corresponding blade (3a).

6. - Electric radiator (1) with heat transfer fluid according to any one of claims 1 to 5, characterized by the fact thatthe diameter of the fluid communication hole (6a) of the lower blade (3a), and where appropriate of the blade immediately above in the position of use of the radiator (1), is less than 8 mm, preferably between 5 and 7.5 mm, more preferably between 5.5 and 7 mm.

7. - Electric radiator (1) with heat transfer fluid according to any one of claims 1 to 6, characterized by the fact that the heating element (5) is of the immersion heater type.

8. - Electric radiator (1) with heat transfer fluid according to any one of claims 1 to 7, characterized by the fact that the collector assembly (2a, 2b) has a tightly closable opening at a lower end in the use position of the radiator (1) for filling the heat transfer fluid (7) inside the radiator (1), if necessary configured to be closed by the heating element (5).

9. - Method for filling with heat transfer fluid an electric radiator (1) with heat transfer fluid according to any one of claims 1 to 8, characterized by the fact that it comprises: placing the interior volume of the radiator (1) under vacuum through an opening in the collector assembly (2a, 2b), introducing a heat transfer fluid (7) through the same opening, suspending the filling of the heat transfer fluid (7) to break the vacuum and allow air (8) to enter the interior volume of the radiator (1), and continuing to fill the interior volume of the radiator (1) with heat transfer fluid (7) until it is completely filled.

10. - Method according to claim 9, for a radiator (1) in which the heat transfer fluid introduction opening (7) is formed in the lower part in the position of use of the radiator (1), characterized by the fact that filling is carried out with the radiator (1) inclined, with its lower end facing upwards.

11. - Method according to claim 9 or claim 10, characterized by the fact that the filling opening is sealed by the heating element (5) after filling.

Images