WO2019081854A1

WO2019081854A1 - Heating unit, heat exchange bundle, electric heating device and associated air-conditioning unit

Info

Publication number: WO2019081854A1
Application number: PCT/FR2018/052646
Authority: WO
Inventors: Erwan Gogmos
Original assignee: Valeo Systemes Thermiques
Priority date: 2017-10-24
Filing date: 2018-10-24
Publication date: 2019-05-02
Also published as: FR3072766B1; FR3072766A1

Abstract

The invention concerns a heating unit (2) formed from a stack comprising a first row of stones (4a) comprising at least a first heating stone (5a), said first row of stones being connected to a first electrode (8a) of the heating unit, a second row of stones (4b) comprising at least a second heating stone (5b), said second row of stones being connected to a second electrode (8b) of the heating unit, characterised in that the first and second rows of stones (4a, 4b) are electrically connected by means of a common third electrode (9).

Description

HEATING UNIT, HEAT EXCHANGE BEAM, ELECTRIC HEATING DEVICE AND AIR CONDITIONING UNIT THEREFOR

Field of the Invention The invention relates to a heating unit. It is especially intended for heating air in a vehicle, in particular a motor vehicle powered by an electric or hybrid motor. It also relates to a heat exchange beam comprising a plurality of such heating units. It also relates to an electric heating device comprising such a beam and an air conditioning unit comprising such a device.

State of the art

Heat exchange bundles equipped with electric heating units for heating vehicles powered by electric or hybrid motors are known. Indeed, in this type of vehicle, conventional cooling systems of the engine through a heat transfer fluid are not sufficient to increase the temperature in the passenger compartment of the vehicle, so that an additional heating source, even alternative, is then essential to ensure the comfort of the driver and the passenger.

The efficiency of the heating provided by this type of heat exchange bundle is essentially due to the possibility of placing a very large number of heating units. Electric heating units are usually composed of heating elements or stones. These heating stones are arranged in rows forming heating lines and electrically connected to a supply module by means of two electrodes. The power module is located within the heat exchanger itself. The device thus obtained is compact and can be integrated in a reduced space of the vehicle.

However, the known devices have several important limitations. Indeed, as illustrated in Figure 1, so that the heating lines can be powered independently of each other: each heating line has its own supply circuit, namely a first electrode 102 and a second electrode 104 for supplying the heating elements 108, so that the operation of the device is based on an electrically functional supply diagram; each heating line is separated from the adjacent heating lines by a double row of heat sinks 106.

Such a heat exchange beam does not have optimal compactness.

The invention aims to improve the prior art by providing a compact heat exchange beam. Improved compactness makes it easier to integrate the device under the dashboard and save space that could be used to implement other functional elements

For this purpose, according to a first aspect, the invention proposes a heating unit formed of a stack comprising:

a first row of stones comprising at least one first heating stone, said first row of stones being connected to a first electrode of the heating unit;

a second row of stones comprising at least one second heating stone, said second row of stones being connected to a second electrode of the heating unit; characterized in that said first and second rows of stones are electrically connected by means of a third common electrode.

The effect of increasing the compactness is thus obtained, according to the invention, by using an electrode common to the two rows of stones, which makes it possible to dispense with an additional electrode and, at least, a row heat sinks.

By "stone" is meant any type of heating element, ceramic or other type, which allows to release heat by being fed with an electric current. According to different features of the invention that can be taken together or separately:

the first row of stones comprises at least one first non-heating stone; the second row of stones comprises at least one second nonheated stone;

the one or more heating and / or non-heating stones are disposed in a non-identical manner from one row to another, so as to generate a heterogeneous heat along the heating unit according to whether one or the other row is powered; - At least one of the first heating stones of the first row of stones is disposed opposite one of the second non-heating stones of the second row of stones;

at least one of the second heating stones of the second row of stones is disposed facing one of the first non-heating stones of the first row of stones;

at least one first stone of the first row of stones is offset longitudinally with respect to at least one second corresponding stone of the second row of stones;

at least one first non-heating strip of the first row of stones is arranged in front of a plurality, at least two, of heating stones of the second row of stones;

at least one second non-heating strip of the second row of stones is arranged in front of a plurality, at least two, of heating stones of the first row of stones; - one of the first heating stones of the first row of stones is arranged vis-à-vis one of the second heating stones of the second row of stones; - The first row of stones comprises at least a first heating stone very little, and the second row of stones comprises at least a second heating stone very little;

at least one of the first few heating stones of the first row of stones is disposed in front of one of the second heating stones of the second row of stones, said first and second rows of stones comprising a plurality, at least two , heating stones and a plurality, at least two, non-heating stones;

at least one of the second stones heating very little of the second row of stones is disposed in front of one of the first heating stones of the first row of stones, said first and second rows of stones comprising a plurality, at least two stones; heaters and a plurality, at least two, non-heating stones;

said first and second rows of stones are electrically connected to the third electrode via at least one element having good electrical conductivity;

the heating unit comprises a metal tube, said rows of stones and said electrodes being inserted into the tube;

said first and second rows of stones and said first and second electrodes are electrically insulated from the metal tube.

said third electrode comprises a heat dissipating element between the first and second rows of stones;

the heating unit comprises a first row of dissipators adjacent to the first row of stones; the heating unit comprises a second row of dissipators adjacent to the second row of stones;

the heating units comprise electrode supports; said electrode supports extend longitudinally, according to the orientation of said rows of stones;

- The heating stones, non-heating and / or heating very few are located vis-à-vis large faces of said supports; - The sink or dissipaters are formed of corrugated inserts.

The invention also relates to a heat exchange bundle comprising a plurality of heating units, as described above.

According to different features of the invention that can be taken together or separately:

said heating units are separated from each other by at least one layer of electrical insulator;

said heating units are separated from each other by at least one electrical insulator disposed on an outer face of said first electrode;

said heating units are separated from each other by at least one electrical insulator disposed on an outer face of said second electrode;

at least one of the heating units comprises first and second rows of stones different from said first and second rows of stones of the other heating units, in particular according to a partition of the beam in at least two parts intended to be traversed by a respective air flow, each air flow being intended to be oriented towards a different area of the vehicle.

The invention also relates to a heating device comprising such a heat exchange bundle and an air conditioning unit, in particular a motor vehicle, comprising a heating device. Presentation of figures

Other objects, features and advantages of the invention will appear more clearly in the description which follows, made with reference to the appended figures, in which: FIG. 1, already commented, schematically illustrates, in front view, a electric heating unit according to the prior art;

- Figure 2a schematically illustrates, in front view, a heating unit according to a first embodiment of the invention;

FIGS. 2b and 2c schematically illustrate, in front view, a heating unit according to several variants of the invention;

- Figure 3 schematically illustrates, in front view, a heating unit according to a second embodiment of the invention;

- Figure 4a schematically illustrates, in front view, a heating unit according to a third embodiment of the invention; FIGS. 4b and 4c schematically illustrate, in front view, a heating unit according to several variants of the invention;

FIGS. 5a and 5b schematically illustrate, in front view, a heat exchange beam in which the rows of stones and the electrodes of each heating unit are integrated in metal tubes (cut in FIG. 5a and not in FIG. cut in Figure 5b);

- Figures 6a and 6b schematically illustrate, in front view, a heating unit according to the invention;

FIGS. 7a and 7b schematically illustrate, in front view, a heat exchange beam comprising a plurality of heating units according to the invention;

- Figures 8a and 8b schematically illustrate, in front view, a heat exchange beam comprising a plurality of heating units according to several variants of the invention. detailed description

As illustrated from Figures 2a to 2c, the invention relates to a heating unit 2 formed of a stack comprising a first row of stones 4a, a second row of stones 4b and, here, a first row of dissipators 3a and a second row of heatsinks 3b. The stacking direction is illustrated by the arrow marked X.

Once assembled into a bundle, the heating units 2 are intended to be traversed by a flow of air that propagates mainly in a direction perpendicular to the direction of the stack X and perpendicular to a direction Y of longitudinal extension of the heating unit 2. In other words, the air flow is oriented in a direction orthogonal to the figures.

The first and second rows of stones 4a and 4b are disposed adjacent one another and interposed between said first and second rows of dissipators 3a and 3b.

The first row of stones 4a comprises at least one first heating stone 5a. Preferably, the first row of stones comprises several, at least two, hot stones 5a. The first row of stones 4a is connected to a first electrode 8a of the heating unit 2. This first electrode 8a makes it possible to apply a specific potential to said first row of stones 4a.

The second row of stones 4b comprises at least a second heating stone 5b. Preferably, the second row of stones comprises several, at least two, hot stones 5b. The second row of stones 4b is connected to a second electrode 8b of the heating unit. Similar to the first electrode 8a, this second electrode 8b makes it possible to apply a specific potential to said second row of stones 4b, preferably identical to the specific potential applied to the first row 4a.

According to the invention, in order to be able to generate heat, said first and second rows of stones, 4a and 4b, are electrically connected by means of a third electrode 9, common to both rows. This common electrode 9 is connected the mass of the device and traversed by a zero potential. The common electrode 9 being connected to the two rows of stones, 4a and 4b, a voltage can be created across them. Thus, as each row of stones is connected to another electrode ie the row of stones 4a is connected to the first electrode 8a and the row of stones 4b to the second electrode 8b, the voltage applied to any of the rows of stones can be changed independently of the voltage applied to the other row of stones. Therefore, the heat generated by any of the rows can be changed independently of the heat generated by the other row. The common electrode 9 can be directly connected to the two rows of stones 4a and 4b. Alternatively, said first and second rows of stones 4a and 4b can be electrically connected to the third electrode 9 via at least one element having good electrical conductivity. Other alternatives that the skilled person will be able to define can be used to connect the common electrode 9 to the two rows of stones.

In a very advantageous manner, the use of the common electrode 9 thus makes it possible to dispense with an additional electrode and at least one additional row of heat sinks.

Such a configuration therefore makes it possible to improve the compactness of each heating unit 2, and substantially the compactness of a heat exchange bundle 1 comprising a plurality of heating units 2.

The heating units may also include longitudinally extending electrode supports 13a and 13b, depending on the orientation of said rows of stones. Preferably, the heating stones, not heating and / or heating very little are located vis-à-vis large faces of said supports 13a and 13b.

Advantageously, the dissipator or dissipaters are formed of corrugated inserts.

Preferably, the first row of stones 4a comprises at least one first non-heating stone 6a. Preferably, also, the first row of stones comprises several, at least two, nonheated stones 6a. The advantages of such a configuration are discussed below. For the purposes of the invention, a non-heating stone is a stone that does not release heat even when subjected to an electric current. Preferably, it is an electrically insulating element which preferably also has a high thermal conductivity, so that the heat generated by the heating stones can propagate easily through the heating unit 2. Advantageously, the non-heating stone according to the invention also makes it possible to prevent the positive electrodes 8a and 8b from coming into contact with the common electrode 9 and thus making it possible to avoid a short circuit within the heating unit 2.

Advantageously, said at least one first heating stone 5a of the first row 4a is located in a first zone of the heating unit 2, while said at least one first non-heating stone 6a is in a second zone of the heating unit 2, so as to form two zones. The first and second zones are arranged in such a way that one, for example the first zone, exchanges heat with a flow of air intended to be directed towards the front passenger side of the passenger compartment of the vehicle, while the other, for example the second zone, exchanges heat with a flow of air intended to be directed towards the driver's side of the passenger compartment of the vehicle.

Thus, advantageously, the first row of stones 4a can generate a high heat on the side comprising the heating stone (s) 5a located in the first zone, while it generates a very high degree of heat. low or zero on the side comprising the non-heating stone (s) 6a located in the second zone.

Preferably, the second row of stones 4b comprises a second non-heating stone 6b. Preferably, also, the second row of stones 4b comprises several, at least two, non-heating stones 6b. Advantageously, the heating stones 5b of the second row 4b are located in the second zone of the heating unit 2, while the non-heating stones 6b are located in the first zone of the heating unit 2.

Thus, particularly advantageously, the heating stones 5b of the second row of stones 4b are arranged in the second zone of the heating unit 2, while the heating stones 5a of the first row of stones 4a are arranged in the first zone. of the heating unit. Therefore, the first row of stones 4a can generate a very high heat on the front passenger side of the passenger compartment, while the second row of stones 4b generates a very low or zero heat in said side. Simultaneously, the second row of stones 4b can generate a very high heat on the driver's side of the cabin, while the first row of stones 4a generates a very low or zero heat in said side.

In such a configuration, since the heating and / or non-heating stones are non-identically arranged from one row to another, there is a spatial modulation effect of the heating ie a heterogeneous heat is generated along the the heating unit 2 according to whether one or the other row is powered. By "arranged in a non-identical manner" is meant in particular arranged differently according to their order of succession in the direction of extension Y of the heating unit 2.

Advantageously, when the number of heating and non-heating stones and / or their distribution are homogeneous on each side of the common electrode 9, this improves the stability and flatness of said common electrode 9. Similarly, when the gap between the stones of each row, 4a and 4b, decreases, the same effect can be obtained.

Referring to Figure 2a, according to a first variant of the invention, at least one of the first heating stones 5a of the first row of stones 4a is disposed vis-à-vis one of the second non-heating stones 6b of the second row of stones 4b, here three, and / or at least one of the second heating stones 5b of the second row of stones 4b is arranged vis-à-vis one of the first non-heating stones 6a of the first row of stones 4a, here three.

As indicated above, said first and second heating stones, 5a and 5b, of said first and second rows of stones are arranged to heat respectively the first zone and the second zone. The electrodes 8a, 8b and 9 make it possible to independently control the rows 4a and 4b and to heat one of said zones if necessary. Very advantageously, such a configuration simultaneously allows the spatial modulation of the heating and obtaining a heating unit 2 more compact. In particular, this spatial modulation of the heating is carried out so that a suitable heat can be generated on one side of the passenger compartment, while zero or very low heat is released on the other side of the passenger compartment. . With reference to FIG. 3, according to a second variant of the invention, at least one first stone of the first row of stones 4a is offset longitudinally with respect to at least one corresponding second stone of the second row of stones 4b.

In the illustrated configuration, at the interface between the two zones, the longitudinal shift of the stones of the first row vis-à-vis the stones of the second row is achieved by moving the heating stone away from one of the rows of the stone heater of the other row at said interface. This promotes the appearance of a "buffer zone" between the first and the second zone, while avoiding the risk of a short circuit between the two rows of stones. For the rest, the spacing between the heating stones and / or unheated of each row remains preferentially constant.

Referring to Figures 4a to 4c, according to a third variant of the invention, at least a first non-heating strip 6a of the first row of stones 4a is disposed opposite a plurality of heating stones 5b of the second row of stones 4b, here three in Figure 4a and two in Figures 4b and 4c, and at least one second non-heating strip 6b of the second row of stones 4b which is disposed opposite a plurality of heating stones 5a of the first row of stones 4a, here three in FIG. 4a and two in FIGS. 4b and 4c.

Such a configuration advantageously makes it possible to simplify the manufacturing process of the device. Indeed, the non-heating stones that are in any one of said first or second zone of the heating unit 2 have the same functions, ie ensure the conduction of heat through the unit so as to heat one of them. any of the first or second zones of the passenger compartment and avoid any short circuit between the electrodes 8a and 8b and the common electrode 9, they can be replaced by one and the same element having the same functions. Conversely, heating strips can be used in place of several hot stones.

Referring to Figure 2b, according to a fourth embodiment of the invention, one of the first heating stones 5a of the first row of stones 4a, is disposed vis-à-vis one of the second heating stones 5b of the second row of stones 4b. For the remainder, the distribution of the stones is in accordance with the embodiment of FIG. 2a, two pairs of successive heating stones being separated by two pairs associating a heating stone of one of the rows with a non-heating stone of the other row. . In such a configuration, one and the same row of stones is capable of generating high heating on one side of the passenger compartment and simultaneously medium or low heating on the other side of the passenger compartment, which allows a spatial modulation of the heat along the heating unit 2, without even applying a potential to the electrode of the other row. In particular, said configuration makes it possible to create an even finer spatial modulation of the heat within any first or second zone of the heating unit 2. Here, each zone comprises four heating stones. When heating is activated in one of the rows, the three heating stones in one zone are energized, while one of the heating stones in the other zone is also energized.

Such a configuration can be obtained according to several variants. We can, for example, refer to Figure 4b, which is a non-limiting example.

Advantageously, the first row of stones 4a comprises at least a very little first heating stone 7a, and the second row of stones 4b comprises at least a second, very little heating stone 7b.

Within the meaning of the invention, a very little heating stone is an element which, without being fully electrically insulating, has a low thermal conductivity so as to be able to heat moderately. The very low electrical conductivity of this type of stone ensures electrical insulation between two rows of elements. With reference to FIG. 2c, according to a fifth variant of the invention, at least one of the first very little heating stones 7a of the first row of stones 4a is disposed in front of one of the second heating stones 5b of the second row of stones 4b and / or at least one of the second very little heating stones 7b of the second row of stones 4b is arranged in front of one of the first heating stones 5a of the first row of stones 4a. For the remainder, the distribution of the stones is in accordance with the embodiment of FIG. 2a, two pairs of successive heating stones being separated by two pairs associating a heating stone of one of the rows with a non-heating stone of the other row. .

Thus, similar to the variants shown in Figures 2b and 4b, a single row of stone is capable of generating a high heating of one side of the passenger compartment and simultaneously a medium or low heat on the other side of the passenger compartment. cabin. The main advantage of this configuration is to allow even finer heating modulation along the heating unit 2.

Such a configuration can be obtained according to several variants. We can, for example, refer to Figure 4c, which is a non-limiting example.

With reference to FIGS. 5a and 5b, the heating and / or non-heating stones and the first, second and third electrodes may be inserted into a metal tube 12 in order to protect its constituent elements of the external environment and to improve its service life. Preferably, said first and second rows of stones, 4a and 4b, and said first and second electrodes, 8a and 8b are electrically insulated from the metal tube 12, so as to avoid short circuits between the various elements of the heating unit 2. Referring to Figures 6a and 6b, the common electrode 9 may comprise a heat sink element 10 interposed between the first and second rows of stones 4a and 4b. The heat dissipating element 10 makes it possible to promote the evacuation of the heat generated by the heating stones. The size of the heat sink element 10 can be adjusted to optimize the compactness of the device. Preferably, the heating unit 2 according to the invention also comprises a first row of dissipators 3a adjacent to the first row of stones 4a and a second row of dissipators 3b adjacent to the second row of stones 4b, so as to form a heating block which can constitute the base element of a heat exchange bundle 1.

With reference to FIGS. 7a, 7b, 8a and 8b, a heat exchange bundle 1 according to the invention comprises a plurality of heating units 2, for example in the form of such heating blocks.

In Figures 7a and 7b, said heating blocks are separated from each other by at least one electrical insulator January 1. The electrical insulator 11 may consist of a layer of material located between the row of dissipators 3a of a first heating unit and the row of dissipaters 3b of a second heating unit, and so on between each heating unit 2. electrical insulation 1 1 may also be disposed on one of the outer faces of said first 8a and second 8b electrodes. In both configurations, each of said heating units 2 is electrically insulated from the other which makes it possible to adjust the heating independently for each unit 2, if necessary simultaneously with the heating of each row of stones.

Advantageously, the heat exchange bundle 1 comprises a plurality of heating units 2, in which first and second rows of stones 4a and 4b are different from said first and second rows of stones 4a and 4b of the other heating units. 2. Many configurations, for example as shown in Figures 8a and 8b, can be envisaged.

The invention also relates to a heating device comprising such a beam. The heater includes, for example, a support frame in which the beam is located. The heating device may further comprise a distribution unit and / or control of the current flowing in the beam. Said frame and a housing of said distribution unit are integral.

The invention also relates to an air conditioning unit comprising such a heating device, advantageously a housing configured to circulate a separate air flow to each of the driver and front passenger areas of the vehicle. Each zones of the heating units are then positioned accordingly in the housing.

Claims

1. Heating unit (2) formed of a stack comprising:

- a first row of stones (4a) comprising at least a first heating stone (5a), said first row of stones being connected to a first electrode (8a) of the heating unit;

- A second row of stones (4b) comprising at least a second heating stone (5b), said second row of stones being connected to a second electrode (8b) of the heating unit; characterized in that said first and second rows of stones (4a,

4b) are electrically connected by means of a third common electrode (9).

2. heating unit (2) according to claim 1, wherein the first row of stones (4a) comprises at least one first non-heating stone (6a) and / or the second row of stones (4b) comprises at least one second stone; non-heating (6b).

The heating unit (2) according to claim 2, wherein the one or more heating and / or non-heating stones are arranged in a non-identical manner from one row to another, so as to generate a heterogeneous heat along the heating unit according to whether one or the other row is powered.

4. heating unit (2) according to claim 3, wherein one of the first heating stones (5a) of the first row of stones (4a), is arranged vis-à-vis one of the second heating stones (5b) the second row of stones (4b).

5. heating unit (2) according to claim 3, wherein: - the first row of stones (4a) comprises at least a first heating stone very little (7a), and the second row of stones (4b) comprises at least one second heating stone very little (7b); at least one of the first few heating stones (7a) of the first row of stones (4a) is arranged in front of one of the second heating stones (5b) of the second row of stones (4b) and / or at least one of the second few heating stones (7b) of the second row of stones (4b) is disposed opposite one of the first heating stones (5a) of the first row of stones (4a).

6. heating unit (2) according to any one of the preceding claims, comprising a metal tube (12), said rows of stones (4a, 4b) and said electrodes (8a, 8b) being inserted into the tube.

7. Heating unit (2) according to the preceding claim, wherein said first and second rows of stones (4a and 4b) and said first and second electrodes (8a and 8b) are electrically insulated from the metal tube (12).

Heating unit (2) according to any one of the preceding claims, wherein said third electrode comprises a heat dissipating element (10) between the first and second rows of stones (4a, 4b).

Heating unit (2) according to any one of the preceding claims, comprising a first row of dissipators (3a) adjacent to the first row of stones (4a) and / or a second row of dissipators (3b) adjacent to the second row of stones row of stones (4b).

A heat exchange bundle (1) comprising a plurality of heaters (2) according to any one of the preceding claims.