CN212064404U - Electric heating device and motor vehicle - Google Patents

Abstract

The utility model relates to an electric heating device, electric heating device includes that heating element holds shell (6), heating element holds shell (6) and constitutes at least one heating rib (22), the heating rib has the U-shaped recess that is used for holding electric heating element (28), and wherein, every U-shaped recess has two relative lateral walls (24), wherein, medial surface (25) of lateral wall (24) have uplift portion (26), the area of uplift portion (26) accounts for at least 50% of the area of whole lateral wall medial surface (25) to have a flat region in uplift portion central authorities. According to the utility model discloses can realize pressing from both sides electric heating element in the U-shaped recess more firmly, ensure to have sufficient heat transfer simultaneously between U-shaped recess and electric heating element. The utility model discloses still relate to a motor vehicle.

Description

Electric heating device and motor vehicle

Technical Field

The utility model relates to an electric heater unit and a motor vehicle that has this electric heater unit.

Background

Such an electric heating device is known, for example, from EP 2884198 a 1. An electric heating device, in particular for heating a temperature control medium in a motor vehicle, comprising a housing which has a pipe connection for connecting pipes which conduct the temperature control medium and which encloses a circulation chamber, into which heating ribs project, which heating ribs are each provided with a U-shaped recess which opens into a uniform connection chamber which is separated from the circulation chamber by a separating wall which is arranged in the region of the open ends of the U-shaped recesses, wherein the heating ribs are arranged one behind the other and offset from one another and alternately close to the walls, so that a meandering flow channel is formed in the circulation chamber. In order to be able to achieve a high thermal output of the electric heating device in a compact configuration, a gap which allows a bypass flow is formed between the longitudinal side wall of the housing which delimits the circulation chamber and the heating ribs opposite the flow channel.

However, in the case where the electric heating apparatus of the prior art vibrates during the operation of the motor vehicle, the electric heating element in the U-shaped recess and the sealing element in the housing may slip, resulting in the abnormal operation of the electric heating apparatus.

SUMMERY OF THE UTILITY MODEL

The task of the utility model is to provide an electric heater unit for prior art improvement, it can be more reliable must move.

The object is achieved by an electric heating device comprising a heating element receiving shell which forms at least one heating rib having U-shaped recesses for receiving an electric heating element, wherein each U-shaped recess has two opposing side walls. The inner side of the side wall has a raised area which occupies at least 50% of the entire area of the inner side of the side wall, and a flat area in the center of the raised area.

According to the invention, the inner side of the side wall of the U-shaped groove is not flat, but has a bulge over at least 50% of the area. A more secure clamping of the electric heating element in the U-shaped recess can be achieved by the elevations, in which the electric heating element does not slip even in the event of strong vibrations of the electric heating device. In addition, there is a flat area in the centre of the elevation, whereby a heat transfer contact is formed, in order to still ensure a sufficient heat transfer between the U-shaped groove and the electric heating element.

According to a further development of the invention, the elevations are constructed symmetrically and the area of the elevations represents at least 80% of the area of the entire side wall inner side.

According to an embodiment of the invention, the electric heating device has a lower housing, the lower housing having a sealing groove for receiving a sealing element for sealing between the lower housing and the heating element receiving shell, a recess being formed on the lower housing inner wall which carries out the inner limit to the sealing groove. Through this recess, an additional tongue-and-groove connection of the circumferential sealing element with the sealing groove can be achieved, so that a better positioning and fixing of the sealing element in the sealing groove is ensured.

According to a further embodiment of the invention, the heating element receiving housing has an auxiliary positioning element on the side facing the connection circuit board, which auxiliary positioning element is used for interacting with a mating positioning element formed on the connection circuit board. This facilitates the mounting of the connection circuit board on the heating element receiving housing and ensures a correct positioning of the connection circuit board on the heating element receiving housing.

According to a development of the invention, the auxiliary positioning element is designed as a projecting strip, and the mating positioning element is designed as a latching hook with a recess. This enables the auxiliary positioning to be achieved with a simple structure.

According to a further development of the invention, the heating element receiving housing has separating elements which separate a high-voltage circuit on the connection circuit board from a low-voltage circuit for the temperature sensor. By separating the high-voltage circuit on the connection circuit board from the low-voltage circuit for the temperature sensor, for example, the measuring harness, the electromagnetic compatibility of the circuit in the heating element accommodating case can be improved.

According to a further development of the invention, the separating element is integrally formed on the heating element receiving shell and extends vertically upwards.

According to a further embodiment of the invention, the heating element housing has a measuring sensor cap for the measuring sensor, which has an extension that projects laterally from a receiving recess for receiving the measuring sensor, and a fillet is formed on the heating element housing, which fillet and extension jointly form an anti-eddy element. By the rounded portion and the elongated extension portion together forming a vortex-preventing element, the fluid flowing into the circulation chamber can be prevented from generating a vortex, thereby enabling more accurate temperature measurement of the measurement sensor at the location.

According to the utility model discloses an extension scheme, electric heater unit is arranged in heating the liquid temperature regulating medium in the motor vehicle.

Furthermore, the invention also relates to a motor vehicle having an electric heating device as described above.

Drawings

Embodiments of the present invention will be described in detail below with reference to the attached drawing figures, wherein:

fig. 1 and 2 show a perspective view of an electric heating device according to a first embodiment of the invention from different perspectives;

fig. 3 shows an exploded view of an electric heating device according to a first embodiment of the present invention;

figure 4 shows a perspective view of the lower housing of an electric heating device according to a first embodiment of the present invention;

fig. 5 shows a top view of a heating element housing shell of an electric heating device according to a first embodiment of the present invention;

FIG. 6 shows a perspective view of a connection circuit board for mounting in the heating element-receiving shell of FIG. 5;

fig. 7 and 8 show perspective views of a heating element housing shell of an electric heating device according to a first embodiment of the invention, from different perspectives;

figure 9 shows a side cross-sectional view of a heating element housing shell of an electric heating device according to a first embodiment of the present invention;

figure 10 shows a perspective view of a heating element housing shell of an electric heating device according to a second embodiment of the present invention;

figure 11 shows a perspective view of a lower housing of an electric heating device according to a second embodiment of the present invention; and

fig. 12 shows a side sectional view of a heating element receiving shell of an electric heating device according to a second embodiment of the present invention.

Detailed Description

Fig. 1 and 2 show assembled states of an electric heating apparatus according to a first embodiment of the present invention at different viewing angles. Fig. 3 shows an exploded view of an electric heating device according to a first embodiment of the invention.

The electrical heating device according to the invention is used in particular for heating a liquid tempering medium in a motor vehicle. As shown in fig. 3, the electric heating device comprises two modular parts, namely a power part L and a control part S.

The power section L mainly comprises the following components shown one above the other on the left in fig. 3: a lower housing 4, a sealing element 32, a heating element accommodating shell 6, an electrical heating element 28 (in particular a PTC heating element) to be mounted in the heating element accommodating shell, a connection circuit board 40, a measuring wire harness 36 and an upper housing cover 48 covering the connection circuit board 40.

The control section S mainly includes a controller case 60 shown in the order from the right in fig. 3, a control circuit board 64 to be mounted in the controller case, a frame arrangement 66 provided between the controller case 60 and the control circuit board 64, and a metallic controller case cover 78.

Two connecting pieces 10 (i.e. an inlet connecting piece and an outlet connecting piece for a circulation chamber 14 in the lower housing 4) project from a first end side of the lower housing 4, which connecting pieces 10 are integrally formed on the lower housing 4 in the form of a plastic injection-molded part and are designed here as pipe connections. The heating element receiving housing 6 defines a separating wall 12 which delimits, on the upper side, a circulation chamber 14 which is also delimited by the walls of the lower housing 4 (i.e. the longitudinal side walls 16 running parallel to the connecting piece 10, the end side walls running at right angles thereto and the bottom wall). A sealing element 32 for sealing between the lower housing 4 and the heating element receiving shell 6 is introduced into a sealing groove 34 which is open at the lower housing 4 and is held there. The sealing element 32 projects beyond the end face of the lower housing 4 on the end side, on which the heating element receiving shell 6 rests. The heating element receiving housing 6 not only serves as a cover for the circulation chamber 14 of the lower housing 4, but also as a receiving seat for the electric heating element 28. The heating element receiving shell 6 forms a plurality of heating ribs 22 with U-shaped recesses, into each of which an electric heating element 28 is inserted, the electric heating elements 28 being in heat-transferring contact against the inner side of the heating ribs 22. The heating element receiving housing 6 also forms two measuring sensor caps 26a and 26b in the region close to the connecting piece 10, which protrude from the heating element receiving housing 6 into the circulation chamber 14.

The connection circuit board 40 is formed from a plastic plate 42 and a metal plate 44 connected thereto and is mounted to a plastic frame 58 of the electric heating element 28. The plastic plate 42 has spacers projecting from its upper side, which are integrally formed on the plastic plate 42 and by means of which the upper housing cover 48 is reliably held spaced apart from the conductor circuits of the circuit board 40. The heating element receiving shell 6 has a circumferential edge 45 which projects beyond the separating wall 12 and which surrounds a connection housing for electrically connecting the contact tongues 28.1 of the heating element 28 to the connection circuit board 40. The measuring wire harness 36 above the electric heating element 28 is electrically connected to the signal output of a measuring sensor 37 introduced into the measuring sensor caps 26a and 26b, the other end of the measuring wire harness 36 being exposed with its measuring wire connection tongue 38. At the top, an upper housing cover 48 is shown, which consists of a stamped and bent sheet metal part and a TPE sealing element sprayed on at the edge, which engages in a sealing groove 54 formed on the circumferential edge 45 and is formed on the heating element receiving housing 6, so as to seal the connecting housing from the environment.

A rod 84 provided for joining the lower case 4 and the heating element accommodating case 6 also belongs to the power section L. The heating element receiving shell 6 and the lower housing 4 have alternately bridging fastening sections, and the rod 84 as a form-locking element locks the heating element receiving shell 6 and the lower housing 4 through the opposite fastening sections of the heating element receiving shell 6 and the lower housing 4.

These components, which constitute the power section L, are fitted to one another in the Z direction in order to form the circulation chamber 14 hermetically on the one hand and to fit the heating element 28 into the U-shaped recess of the heating element receiving shell 6 on the other hand and to be electrically connected to the connection circuit board 40 by means of contact tongues 28.1 projecting upwards from the heating element 28. The measurement sensors are also incorporated into the measurement sensor caps 26a and 26b in this engagement direction and are electrically connected by a measurement harness 36. Finally, the arrangement is covered and sealed by the upper housing cover 48, so that the electrical circuit provided in the connection chamber 30 is also sealed off from the environment on the upper side.

Similarly to the upper housing cover 48, the control housing cover 78 is produced from a stamped sheet metal and has metal snap-on means formed in one piece thereon by stamping and bending, which interact with the wall of the control housing 60 in order to form a peripheral shield which surrounds the connection circuit board 40 on the one hand and the control circuit board 64 equipped with the power transistors 62 on the other hand.

The power plug 80 is fixed to the outside of the controller housing 60 by two fixing pins 82, and the control plug 72 is fixed to the outside of the controller housing 60 by the fixing screws 70. The ground terminal 76 is mounted in a ground terminal receiving portion on the side of the controller case 60, and protrudes beyond the controller case 60 toward the power portion L in a mounted state. The fixing screws 68 are used to fix the metallic controller case 60 to the metallic heating element accommodation case 6 to achieve the assembly of the power section L and the control section S together.

After the complete preassembly of the power section L, the printed circuit board 40 projects beyond the power section L not only with its printed circuit board terminal lugs formed by the stamped metal sheet 44 but also through the end section of the plastic sheet 42. For this purpose, the heating element receiving housing 6 has a through-opening for connecting a circuit board in the circumferential edge 45 on the side facing the control section S.

According to fig. 4, a partition wall 20 is formed on the lower housing 4, which partition wall 20 extends parallel to the direction of extension of the connecting piece 10 from one end side to the other end side of the lower housing 4. The circulation chamber 14 is divided by a partition 20 into a first sub-circulation chamber 14a and a second sub-circulation chamber 14b, wherein the two connection ports 10, i.e. the inlet port and the outlet port, each open into one sub-circulation chamber 14a, 14 b. In addition, a measuring sensor cap 26a, 26b is associated with each of the sub-circulation chambers 14a, 14 b.

It can also be seen from fig. 4 that a recess 23 is formed in the inner wall which delimits the sealing groove 34 of the lower housing 4 on the inside. Through this recess 23, an additional tongue-and-groove connection of the circumferential sealing element 32 with the sealing groove 34 can be achieved, so that a better positioning and fixing of the sealing element 32 in the sealing groove 34 is ensured.

According to fig. 5, the heating element receiving housing 6 has, on the side of the separating wall 12 facing the connection circuit board 40, auxiliary positioning elements 20 for cooperation with mating positioning elements 21 (see fig. 6) formed on the connection circuit board 40 in order to facilitate the mounting of the connection circuit board 40 on the heating element receiving housing 6 and to ensure a correct positioning of the connection circuit board on the heating element receiving housing 6. The auxiliary positioning element is preferably integrally formed on the surrounding edge 45 of the heating element receiving shell and projects inwardly. In this embodiment, the auxiliary positioning element 20 is arranged substantially in line with the leftmost U-shaped recess and the free end of the auxiliary positioning element 20 is spaced from the U-shaped recess to ensure that the auxiliary positioning element does not interfere with the mounting of the electric heating element. Of course, the auxiliary positioning member 20 may be provided at any suitable position on the heating element accommodating case 6. In this exemplary embodiment, the auxiliary positioning element 20 is designed as a projecting strip, while the mating positioning element 21 is designed as a latching hook with a recess. Other forms of auxiliary positioning structures are also possible, as long as the auxiliary positioning function of the connection circuit board 40 on the heating element accommodating case 6 can be achieved.

As can be seen from fig. 7, the heating element receiving shell 6 has a separating element 17. These partition elements 17 are integrally formed on the heating element accommodating case 6 and extend vertically upward. Advantageously, the separating element 17 extends to a height not exceeding the encircling edge 45 of the heating element receiving shell 6, and the separating element 17 extends laterally at a distance from the encircling edge 45. When the connection circuit board 40 is mounted on the plastic frame 58 of the electric heating element 28, these separation elements 17 separate the high-voltage circuit 27 (see fig. 6) on the connection circuit board from the low-voltage circuit (measuring harness 36) for the temperature sensor in order to improve the electromagnetic compatibility of the circuit in the heating element housing case.

As can be seen in fig. 8, a partition wall 50 is also formed on the heating element accommodating case 6, and this partition wall 50 cooperates with the partition wall 20 of the lower housing 4 to achieve the continuous separation of the circulation chamber into the first and second sub-circulation chambers.

The measurement sensor cap 26 has an elongated projection 18 projecting laterally from the receiving recess 29 for receiving the measurement sensor 37, the projection 18 having a tail-like shape. The projection 18 extends towards the partition wall 50 and ends at a distance from the partition wall 50, so that a gap is formed between the free end of the projection and the partition wall 20. In addition, the free end of the projection is bent toward the U-shaped groove such that a reduced gap is formed between the free end of the projection and an adjacent one of the U-shaped grooves.

At the end of the partition wall 50 close to the measurement sensor cap 26, a fillet 19 is formed between the partition wall 50 and the surrounding side wall of the heating element receiving shell 6, which fillet is mirror-symmetrical with respect to the center line of the partition wall 50 and is configured, for example, in the form of a roughly semicircular segment. A gap is also present between the rounded portion 19 and the protruding portion 18. The rounded portion and the elongated projection together form an anti-vortex element to prevent the fluid flowing into the circulation chamber from generating vortices, thereby enabling a more accurate temperature measurement of the measuring sensor at the location. Preferably, the lower housing 4 is also provided with a corresponding projection and a corresponding fillet, opposite the projection 18 and the fillet 19. The projections 18 and the rounded portions 19 of the heating element receiving shell 6 cooperate with corresponding projections and rounded portions of the lower housing 4 in order to better prevent eddy currents from occurring and thus to further improve the measurement accuracy of the measuring sensor.

According to fig. 9, each U-shaped recess of the heating element accommodating shell 6 has two opposite side walls 24. The two opposite side walls do not extend parallel to one another but taper toward the lower housing 4 at an angle α to one another, preferably less than 5 degrees, particularly preferably equal to 3 degrees. In this embodiment, the U-shaped groove has a length of 40mm to 50mm and the gap between the opposing sidewalls of the U-shaped groove is 5mm to 7.5 mm. In addition, the inner side 25 of the side wall 24 is not flat, but has a raised portion 26, which is shown in detail in fig. 12, which shows a second embodiment of the electric heating device, for example).

Fig. 10 and 11 show an electric heating device according to a second embodiment of the present invention. In this embodiment, the connection end face 46 'of the heating element accommodating case 6' and the connection end face 47 'of the lower case 4' do not extend parallel to the bottom wall of the lower case 4 'as in the first embodiment of the electric heating apparatus, but extend obliquely to the bottom wall of the lower case 4', so that the heating element accommodating case 6 'and the lower case 4' each have a substantially triangular cross section. In addition, this embodiment also differs from the first embodiment of the electric heating device in that the longitudinal direction of the heating ribs 22' is parallel to the direction of extension of the connecting stub. In this embodiment, four heating ribs 22 'are integrally formed on the heating element accommodating case 6', two longer heating ribs 22 'being located at the center and two shorter heating ribs 22' being located at both sides, respectively, wherein each accommodating rib is capable of accommodating at least two electric heating elements. The measuring sensor caps 26a ', 26 b' are integrally formed on the heating element receiving shell 6 'on both sides of the two longer heating ribs 22'.

Fig. 12 is a sectional view of the heating element receiving shell 6' according to fig. 10, wherein the sectional plane is parallel to the extension direction of the heating ribs and passes through a measuring sensor cap. Fig. 12 shows a specific structure of the inner side surface 25 'of the side wall of the U-shaped recess of the heating element accommodating case 6' in the second embodiment of the electric heating apparatus according to the present invention, which is the same as the structure of the inner side surface of the side wall of the U-shaped recess in the first embodiment. As can be seen from fig. 12, the inner side 25 ' of the side wall has a bulge 26 ', which bulge 26 ' is, for example, crowned, so that it bulges to a greater extent from the edge to the center. The area of the ridge 26 'occupies at least 50%, preferably at least 80%, of the area of the entire side wall inner side face 25'. Advantageously, a flat area is formed in the centre of the ridge. Preferably, the elevation 26' is constructed as a symmetrical structure. A more secure clamping of the electric heating element in the U-shaped recess is achieved by the elevations 26', so that the electric heating element cannot fall out of the U-shaped recess even in the event of strong vibrations of the electric heating device. The flat area ensures sufficient heat transfer between the U-shaped groove and the electric heating element. Preferably, the flat region projects 1mm to 2mm relative to the inner side of the side wall.

The above examples show or describe possible embodiments of the invention, wherein it is to be noted here that various different combinations of the individual embodiments with one another are also possible. In addition, the present invention is not limited to the above description. The present invention can be modified and changed in various ways without departing from the spirit and scope of the present invention.

Finally, it is pointed out that in the figures some parts are not shown to scale and/or enlarged and/or reduced in order to facilitate the understanding of the structure of the individual components of the electric heating device.

Claims (10)

1. An electric heating device comprising a heating element receiving shell (6), the heating element receiving shell (6) constituting at least one heating rib (22) having a U-shaped recess for receiving an electric heating element (28), wherein each U-shaped recess has two opposing side walls (24), characterized in that the inner side surfaces (25) of the side walls (24) have a bulge (26), the area of the bulge (26) occupying at least 50% of the area of the entire side wall inner side surface (25), and in that there is a flat area in the middle of the bulge.

2. Electrical heating device according to claim 1, characterised in that the elevations are constructed symmetrically and the elevations (26) have an area which accounts for at least 80% of the area of the entire side wall inner side (25).

3. Electrical heating device according to claim 1, characterized in that the electrical heating device has a lower housing (4), the lower housing (4) having a sealing groove (34) for receiving a sealing element (32) for sealing between the lower housing (4) and the heating element receiving shell (6), a recess (23) being formed in the inner wall of the lower housing which delimits the sealing groove (34) on the inside.

4. Electrical heating device according to one of claims 1 to 3, characterized in that the heating element receiving housing (6) has an auxiliary positioning element (20) on the side facing the connection circuit board (40) for cooperating with a cooperating positioning element (21) formed on the connection circuit board (40).

5. Electrical heating device according to claim 4, characterized in that the auxiliary positioning element (20) is configured as a projecting strip and the co-operating positioning element (21) is configured as a catch with a recess.

6. Electrical heating device according to any one of claims 1 to 3, characterised in that the heating element receiving housing (6) has separating elements (17), which separating elements (17) separate a high-voltage circuit (27) on the connection circuit board from a low-voltage circuit for the temperature sensor.

7. Electrical heating device according to claim 6, characterised in that the separating element (17) is integrally formed on the heating element receiving shell (6) and extends vertically upwards.

8. Electrical heating device according to one of claims 1 to 3, characterized in that the heating element receiving housing (6) has a measuring sensor cap for the measuring sensor (37), which measuring sensor cap has a projection (18) which projects laterally from a receiving recess (29) for receiving the measuring sensor (37), wherein a rounded portion (19) is formed on the heating element receiving housing (6), which rounded portion together with the projection (18) forms an anti-eddy element.

9. Electrical heating device according to any of claims 1-3, wherein the electrical heating device is used for heating a liquid tempering medium in a motor vehicle.

10. Motor vehicle, characterized in that it has an electric heating device according to any one of claims 1 to 9.

Images