EP1522440B1 - Electric heater for the heating of air, in particular for a motor vehicle - Google Patents

Description

The present invention relates to a device for exchanging heat, in particular for motor vehicles. In motor vehicle air conditioning systems, electrical heating devices are increasingly being used, which serve, for example, to defrost the windshield immediately after departure, or to heat the interior of the vehicle.

In the prior art heating devices are known, which have a heating element, in particular a PTC heating element, which heats up as a result of a current passing through it. In this case, contact plates are provided which are in electrical connection with the heating element and on the other hand are connected to a voltage source.

As a connection between the voltage source and the contact plates riveted plug connections are known in the art. However, these riveted plug connections have the disadvantage that they offer only a relatively small contact surface between the contact plate and the plug connection. This in turn causes the occurrence of relatively high temperatures due to a current flow between the plug connection and the contact plate.

Heating devices of the type mentioned are, for example. In the FR 2 794 605 and in the US 6,055,360 described. The latter relates to a heater with electrical heating elements and associated contact plates. To connect the contact plates to the power / voltage supply is a connection device (wire plate) with a receptacle, in which the end-side tabs of the contact plates are inserted, provided. However, such a connection device of the type shown for connecting the contact plates to the power or voltage supply has various disadvantages. Over time, due to vibration and moisture to aging and corrosion processes, so that the electrical contact at the junctions to the contact plate toward or for power / voltage supply increasingly deteriorates. This leads to an unfavorable increase in the contact resistance and / or to a loose contact at the respective connection points.

Further, the EP-A-1 502 784 the applicant, which constitutes a prior art under Article 54 (3) EPC, an electric heating device for a motor vehicle, on which the preamble of claim 1 is based. In this heating device, an electrical connection device for connecting a first or second contact sheet to a power source is provided. This connecting device is formed with a connecting device for clamping connection of a tab on the side of the power source; their connection with a tab of the contact plates via a riveted joint.

The invention has for its object to improve the connection of the power source or voltage source to the contact plate.

According to the invention this is achieved by a device for exchanging heat according to claim 1 and by a method for producing such a device according to the independent claim. Advantageous embodiments and further developments are the subject of the dependent claims.

The present invention relates to a device for exchanging heat, in particular for a motor vehicle, with at least one first component, which is connected to an electric current source and whose temperature changes in dependence of a current flowing through the component, and at least one second component, which at least one first and at least one second subunit, which are connected to opposite poles of the power source and each at least indirectly in electrically conductive connection with the first Component, wherein at least one subunit has an end-side first tab.

In addition, at least one electrical connection device is provided, which is in electrically conductive connection by means of a first connection device with the first lug of the at least one subunit and serves to connect to the electrical power source, wherein the connection device for connection to the electrical power source at least one second connection device with a Has receiving device for a second tab.

According to the invention, the first connection device of the connection device has a receiving device with a flat section and at least one clamping device. In the assembled state, the receiving device of the first connecting device and the first tab of the at least one subunit of the at least one second component engage each other such that a frictional and positive connection between this receiving device and the first tab is effected by means of the at least one clamping device and an electrical contact between at least the flat portion of the receiving device and a flat portion of the first tab of the at least one subunit is formed.

In the context of the present invention, a connection device is understood to mean any device which, by cooperating with a further connection device, effects a substantially non-positive connection between the two connection devices. As a connection means, for example, a clamp would be understood, which clamps a pin, or a plate. But even at least partially interlocking or interlocking devices are understood as a connection device in the sense of the invention.

An electrical connection device is understood to be a device by means of which the connection to an electrical current source can be established.

A flat section is understood to mean a section that forms a surface having a predetermined length and a predetermined width. This area section can, for. B. represent the surface of a plate-shaped element.

Under a clamping element while such elements are understood to be biased and have at least two sections in order to exercise a clamping force on another element can.

Preferably, at least one clamping element presses the two-dimensional sections of at least the receiving device and the second tab against one another and, in a further preferred embodiment, has at least one curved section.

Particularly preferably, the receiving device of the first connecting device, two clamping elements as the at least one clamping device.

In a further preferred embodiment, the first tab is at least partially surrounded by the receiving device substantially. The term "substantially surrounded" is understood to mean that the surrounding connection device does not completely surround the surrounding connection device, but surrounds a predetermined proportion of the circumference of the surrounding connection device that is greater than 50%, preferably greater than 60% and particularly preferably greater than 70% ,

In a further preferred embodiment, the first and the second connecting device are pressed together, whereby preferably a positive and / or non-positive connection between the connecting devices is formed.

In another preferred embodiment, at least the attachment means is at least partially made of a material selected from a group of materials including copper, brass, but especially tin-plated brass, aluminum, iron, and the like.

In a further preferred embodiment, at least the connection device contains nickel (Ni) with a percentage between 0.2% and 5%, preferably between 0.5% and 3%, and more preferably between 0.8% and 1.8%.

Preferably, at least the connection device contains silicon (Si) with a percentage of between 0.05% and 2%, preferably between 0.1% and 1% and particularly preferably between 0.15% and 0.35%.

In a further preferred embodiment, at least the connection device contains phosphorus (P) with a percentage of between 0.001% and 1%, preferably between 0.005% and 0.3% and particularly preferably between 0.01% and 0.1%.

Particularly preferably, at least the connection device contains nickel with a percentage of 0.8% to 1.8%, silicon with a percentage of 0.15% to 0.35%, phosphorus with a percentage of 0.01% to 0.1% and copper with the difference percentage resulting from the deduction of 100% nickel, silicon and phosphorus shares.

It has been found that the amounts of the individual constituents mentioned above contribute to ensuring a reliable functioning of the plug connection in a wide temperature range. Thus, a reliable operation of the compounds in a temperature range at least from -40 degrees Celsius to 130 degrees Celsius is possible, with the specified high temperatures may arise, for example, by an interaction of high ambient temperature and additional heating by electricity.

In a further preferred embodiment, at least the connection device consists at least partially of brass (CuZn) and particularly preferably of tinned brass. In a further preferred embodiment, at least the connection device is connected to a cable. This cable is preferably used to connect the connecting device to a pole of a voltage source. Preferably, at least the connection device is connected to a control and / or regulating device which controls and / or regulates the current flowing through the first component.

In a further preferred embodiment, at least one subunit of at least one second component is made of a group of materials including copper, brass, but especially not tin-plated brass, iron and the like.

Preferably, the first component comprises at least one heater selected from a group of heaters having PTC heating elements, resistance heating elements, plasma heating elements, and the like.

In a further preferred embodiment, a multiplicity of first and second subunits are provided, which are arranged alternately, the first components preferably being arranged between the subunits. The first and second subunits are preferably contact plates, which are connected to the opposite poles of a voltage source. The alternating arrangement ensures that a current flow through the first component, which is respectively arranged between the subunits, occurs. It would be possible to arrange the first components directly between the first and second subunits, but it is preferred to provide between the respective subunits further, in particular current-conducting elements such as corrugated fins, additional contact plates and the like.

In a further preferred embodiment, the receiving device of the second connecting device of the connecting device is a clamping device. Preferably, the second tab engages in the clamping device such that a non-positive and / or positive, releasable connection is formed.

In a further preferred embodiment, at least one tab has at least one partially rounded and / or beveled end region. This end region preferably serves to facilitate a telescoping of the respective connecting devices.

In a further preferred embodiment, at least one planar section has at least one electrically conductive, structured subsection. Preferably, this is structured by surface shapes taken from a group including ridges, ridges, burls, holes, recesses, roughenings or the like.

In a further preferred embodiment, the longitudinal directions of the first and the second tab are substantially parallel to one another. A coincidence of the longitudinal directions is also understood to be parallel in the sense of this invention. In this case, the longitudinal direction of the first end-side tab preferably coincides with the longitudinal direction of the subunit of the second component.

In a further preferred embodiment, the first and the second tab in the assembled state are rotated by a predetermined angle α with respect to the longitudinal direction of the tabs. This is to be understood to mean that the flat portions of the two tabs are rotated by the predetermined angle to each other. Preferably, this angle α is between 0 degrees and 90 degrees, preferably between 0 degrees and 45 degrees more preferably between 0 degrees and 20 degrees. In a further preferred embodiment, the angle α is approximately 90 degrees.

The inventive method for producing a device according to the invention is characterized in that the connection device and the second tab are pressed together.

The structuring of at least one electrically conductive subsection of the receiving device according to the invention is preferably carried out by surface shaping during punching and / or in at least one shaping process.

The present invention is further directed to the use of the above-described apparatus for exchanging heat in an air conditioning system, in particular a motor vehicle.

Further advantages and embodiments of the device according to the invention for the exchange of heat will become apparent from the accompanying drawings.

Fig. 1

die Gesamtdarstellung einer Vorrichtung zum Austausch von Wärme;

Fig.2

eine Verbindungseinrichtung gemäß dem Stand der Technik;

Fig. 3

eine Rückansicht der Verbindungseinrichtung gemäß Fig. 2;

Fig. 4

eine perspektivische Darstellung einer erfindungsgemässen Verbindungseiririchtung;

Fig. 5

eine Seitendarstellung der erfindungsgemässen Verbindungselnrichtung gemäß Fig. 4;

Fig. 6

eine Draufsicht auf die Verbindungseinrichtung gemäß Fig. 4;

Fig. 7

eine weitere Draufsicht entlang der Linien A-A gemäß Fig. 6.

Show:

Fig. 1

the overall view of a device for the exchange of heat;

Fig.2

a connection device according to the prior art;

Fig. 3

a rear view of the connecting device according to Fig. 2 ;

Fig. 4

a perspective view of an inventive Verbindungseiririchtung;

Fig. 5

a side view of the inventive Verbindungselnrichtung according to Fig. 4 ;

Fig. 6

a plan view of the connecting device according to Fig. 4 ;

Fig. 7

a further plan view along the lines AA according to Fig. 6 ,

In Fig. 1 a device 1 for the exchange of heat is shown in an overall representation.

In this case, the reference numeral 2 refers to a frame and terminal device, which serves the supply of electrical energy into the device for exchanging heat. The reference numeral 6 refers to a first component, which may be in particular, but not exclusively, a PTC element. At this first component is a subunit 7 and 9 of a second component. This subunit can in particular, but not exclusively, be a contact plate. This contact plate has an end tab 3, which serves to supply electrical energy.

Also, the reference numeral 10 refers to a second subunit of the second component, which also has a connection component or tab 12. This tab 12 is preferably connected to the opposite pole 5 of a current or voltage source, so as ultimately a current flow to create by the first component 6 and thus a heating of the same. Furthermore, corrugated fins 8 are provided between the individual first components, which serve to promote the heat exchange with the surrounding air. Reference numeral 15 refers to a frame means for fixing the above-mentioned means.

Fig. 2 shows a conventional connection means between the metal unit or the contact plates of the second component 7 and a terminal lug or a connecting device 21. In this case, a rivet connection 23 is provided. Reference numeral 24 refers to a tab, not visible in the upper picture, with an opening 23 'intended for the riveted connection. A disadvantage of this rivet connection, as stated above, is that a relatively small contact surface between the subunit 7 and the terminal lug 21 is available. This lower contact surface ultimately results in the same current flow to an elevated temperature at the junction.

Fig. 3 shows the connection of the contact plate 7 and the terminal lug 21 in a rear view. Again, the rivet 23 is clearly visible.

Fig. 4 shows a connection device 30 according to the invention for the device 1 for the exchange of heat. In place of in Fig. 3 shown rivet 23 here a clamping connection with two clamping devices 35a and 35b between a first tab 24 of a subunit 7 of the second component and the connection device 30 is used. The tab 24, in this embodiment, has two beveled end portions which facilitate insertion into the clamps 35a and 35b. In addition, rounded corners and the like could be provided. These clamping devices 35a and 35b cause the tab 24 to be pressed against a flat section 36 of the connection device 30. Reference numeral 39 here denotes a second tab of the leadframe 2, which in the second connection means 32 and in the Terminals 31 can preferably be inserted releasably: The elements 31 are in this embodiment to resilient elements that ultimately favor pinching the tab 39. The first tab 24 has a predetermined width b.

In Fig. 5 is a page representation of the presentation Fig. 4 shown. It can be seen that the clamping device 35b presses the tab 24 against the flat portion 36 of the connection device 30. In this way it is achieved that a contact surface between the tab 24 and the flat portion 36 is formed, which results essentially from the product of the width b of the tab 24 and the height h, in which surface portion 36 and the tab 24 overlap results. Furthermore, a contact still comes along the respective side surfaces of the connecting device or the tab 24 and, as in Fig. 4 shown partially on the upwardly facing surface of the tab 24 state.
As it turned out Fig. 5 results, the terminals 31 in cross-section on a beak-shaped. In this case, the clamps initially run in a V-shaped manner in a lower section in the figure, then have a section in which they contact each other and then again run apart in a substantially V-shaped manner. The opening angle above the Berührabschnitts in this embodiment is greater than below the Berührabschnitts. In the assembled state, the two Berührabschnitte the terminals 31 put on the second tab 39, which is indicated by the thin line. In this embodiment, two clamps 31 were used. However, it would also be possible to provide more or fewer clamps instead. Also, a different number of clamping member units could be provided on the two sides.

The two clamping devices 35a and 35b in turn have end sections 35'a and 35'b (cf. Fig. 4 ), which cause a further increase in the contact area between the connecting device 30 and the first tab 24.

However, it is also possible to design the embodiments of the connecting devices in reverse order, d. H. Furthermore, it would also be conceivable to provide clamping devices on both the connecting device 30 and the first tab 24, which engage in one another.

Fig. 6 shows a plan view of the in the 4 and 5 Shown connection device 30. It can be seen here that the end sections 35'b and 35'a are enlarged relative to the remaining sections of the clamping devices 35a and 35b along the direction h. Furthermore, it can be seen that the first tab 24 has a bevelled end portion 26 which facilitates collapse for making the connection between the connectors 24 and 34.

In Fig. 7 is a sectional view along the lines AA on the device Fig. 6 shown. In this case, the regions in which the mechanical connection between the connection device 30 and the first lug 24 comes about are represented in particular by hatching. It can also be seen here that the area of the first lug 24 surrounded by the clamps 35a and 35b is also available as the contact surface in the area defined by the width b and the height h, as mentioned above. In this case, it is also possible to bring the end regions 35a 'and 35b' closer to the center line M in order in this way to further increase the contact surface.

As it turned out Fig. 7 shows, the clamping means 35a and 35b each have an arcuate portion, each having a lateral region the tab 24 at least partially surrounds. In this case, the clamping devices preferably contact the lug 24 along substantially this entire arcuate section. Substantially along this entire arcuate section, it is understood that nevertheless in smaller areas, in which the lug 24 faces a strong curvature of the clamping devices 35a and 35b, such as in the FIG. 7 on the underside of the tab 24 sections, no contact may occur.

The arcuate portion may be made such that it extends at least partially in the shape of a circular line, but other courses such as elliptical courses are also conceivable.

Furthermore, it can be seen that the thickness of the tab 24 projects beyond the thickness of the flat section 36 (indicated by hatching). However, it would also be possible to choose the thicknesses equal or the thickness of the tab 24 is less than the thickness of the flat portion 36th

Further, in this embodiment, the thickness of the sheet portion 36 is substantially equal to the thickness of the clamps 35a and 35b. However, the thicknesses could also be chosen differently.

By suitable methods, such as pressing, it can be achieved that a contact between the connecting device 30 and the tab 24 substantially completely along the lines I1 and I2 comes about.

The reference numeral 33 refers to a central region of the connecting device 30. This central region has a predetermined height and a substantially rectangular cross section, wherein at the respective longitudinal sides of this central region, the clamping devices 31 for the second tab 39 are arranged. However, instead of substantially rectangular cross sections, other cross sections could be used, such as generally polygonal cross sections, elliptical cross sections, and the like.

In FIG. 4 the central region 33 is not a closed region, but is interrupted on its upper side in the longitudinal direction. In cross-section, the central region has rounded corners. The underside of the central region 33 merges directly into the planar section 36, the width of the central region substantially coinciding with the width of the planar section 36.

Preferably, the central region 33 is made of a current-insulating material or surrounded by such a material.

Claims (29)

1. Device (1) for exchanging heat, in particular for a motor vehicle, with
   at least one first component (6), the temperature of which changes depending on a current flowing through this component;
   at least one second component, comprising at least one first part element (7) and at least one second part element (9), which is connected to one of the opposite terminals of the electrical power supply and each of which are at least indirectly conductively connected to the first component (6), wherein at least one part element (7, 9) comprises a first link plate at its end; and
   at least one electrical contact means (30) for the connection to one of the terminals of the power supply, which is conductively connected to the first link plate (24) of the at least one part element (7, 9) by means of a first connecting means (34) and serves to connect to the electrical power supply,
   wherein the contact means (30) comprises at least a second connecting means (32) with a receiving means (31) to receive a second link plate (39) to connect to a electrical power supply,
   characterized in that
   the first connecting means (34) of the contact means (30) comprises a receiving means with a flat portion (36) to engage with the first link plate (24) or
   the first connecting means (34) of the contact means (30) comprises a further link plate and the first link plate (24) comprises a receiving means with a flat portion (36) to engage with a further link plate; and
   in assembled state the receiving means engages with the engaging link plate (24) such that a force-fitting and form-fitting connection is effected between the receiving means and the engaging link plate (24) via at least a clamping means (35a, 35b) and an electrical contact is established between at least the flat portion (36) of the receiving means and a flat portion of the engaging first link plate (24) of the at least one part element (7, 9).
2. Device according to claim 1, characterized in that
   the at least one clamping means (35a, 35b) urges the flat portions of the receiving means and of the first link plate (24) against one another.
3. Device according to claim 1 or 2, characterized in that
   the at least one clamping means (35a, 35b) comprises at least one curved portion.
4. Device according to at least one of the preceding claims, characterized in that the at least one clamping means of the receiving means of the first connecting means (34) comprises two clamping elements (35a, 35b).
5. Device according to at least one of the preceding claims, characterized in that the first link plate (24) of the at least one part element (7, 9) is at least sectionally surrounded by the receiving means of the first connecting means (34).
6. Device according to at least one of the preceding claims, characterized in that the contact means (30) is made at least partially from a material selected from a group of materials including copper, brass, in particular but not exclusively tin-plated or zinc-coated brass, aluminium, iron and the like.
7. Device according to at least one of the preceding claims, characterized in that die contact means (30) comprises nickel at a percentage between 0,2% and 5%, preferably between 0,5% and 3% and particularly preferably between 0,8% and 1,8%.
8. Device according to at least one of the preceding claims, characterized in that the contact means (30) comprises silicon at a percentage between 0,05% and 2%, preferably between 0,1 % and 1% and particularly preferably between 0,15% and 0,35%.
9. Device according to at least one of the preceding claims, characterized in that the contact means (30) comprises phosphorus at a percentage between 0,001 % and 1%, preferably between 0,005% and 0,3% and particularly preferably between 0,01% and 0,1%.
10. Device according to at least one of the preceding claims, characterized in that the contact means (30) comprises nickel at a percentage of 0,8% to 1,8%, silicon at a percentage of 0,15% to 0,35%, phosphorus at a percentage of 0,01% to 0, 1 % and copper at the balance percentage resulting from subtracting the portions of nickel, silicon and phosphorus.
11. Device according to at least one of the preceding claims, characterized in that the contact means (30) is at least partially made of brass.
12. Device according to at least one of the preceding claims, characterized in that the contact means (30) is at least partially made of tin-plated brass.
13. Device according to at least one of the preceding claims, characterized in that the contact means (30) is connected to a cable.
14. Device according to at least one of the preceding claims, characterized in that the contact means (30) is connected to a control system.
15. Device according to at least one of the preceding claims, characterized in that the at least one part element (7, 9) of the at least one second component is made of a group of materials including copper, brass, in particular but not exclusively tin-plated or zinc-coated brass, iron and the like.
16. Device according to at least one of the preceding claims, characterized in that the first component (6) comprises at least one heating element selected from a group of heating elements comprising PTC heating elements, resistance heating elements, plasma heating elements and the like.
17. Device according to at least one of the preceding claims, characterized in that a plurality of first and second part elements (7, 9) are provided in an alternating arrangement.
18. Device according to at least one of the preceding claims, characterized in that corrugated ribs are provided between a plurality of first components (6).
19. Device according to at least one of the preceding claims, characterized in that the receiving means (31) of the second connecting means (32) of the contact means (30) is a clamping means.
20. Device according to claim 19, characterized in that
    the second link plate (39) engages with the clamping means (31) so as to establish a detachable connection.
21. Device according to at least one of the preceding claims, characterized in that the first and/or the second link plate (24, 39) comprises at least a partially rounded and/or bevelled end portion (26).
22. Device according to at least one of the preceding claims, characterized in that at least one flat portion of the first connecting means (34) and of the first link plate (24) comprises at least one electrically conductive, structured subsection.
23. Device according to claim 22, characterized in that
    the at least one electrically conductive, structured subsection is structured by surface shapes from a group including ridges, fins, naps, fishskin texture, holes, recesses, roughenings and the like.
24. Device according to at least one of the claims 1 to 23, characterized in that the longitudinal directions of first and second link plates (24, 39) are substantially parallel.
25. Device according to at least one of the claims 1 to 23, characterized in that
    in assembled condition the first and the second link plate (24, 39) are twisted relative each other by a specified angle α relative the longitudinal direction of the link plates.
26. Device according to claim 25, characterized in that
    the angle α is between 0 and 90°, preferably between 0° and 45° and particularly preferably between 0° and 10°.
27. Procedure to manufacture a device according to at least one of the claims 1 to 26, characterized in that
    the first link plate (24) of the at least one part element (7, 9) is pressed onto the first connecting means (34) of the contact means (30).
28. Procedure according to claim 27 to manufacture a device according to claim 22 or 23, characterized in that
    the structuring of the at least one electrically conductive subsection of the receiving means of the contact means (30) is performed by surface shaping while stamping and/or during at least one shaping process.
29. Use of a device according to at least one of the claims 1 to 26 in an air conditioner, in particular of a motor vehicle.

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