GB2620111A

GB2620111A - Heat dissipation housing

Info

Publication number: GB2620111A
Application number: GB2209020.3A
Authority: GB
Inventors: Aronet Vlad; Stetcu Alina; Barbuta Ioan; Ionescu Robert-Daniel
Original assignee: Continental Autonomous Mobility Germany GmbH; Continental Automotive Romania SRL
Current assignee: Continental Autonomous Mobility Germany GmbH; Continental Automotive Romania SRL
Priority date: 2022-06-15
Filing date: 2022-06-20
Publication date: 2024-01-03
Also published as: GB202209020D0

Abstract

A housing 10 of a vehicular camera assembly cools a heat-generating element of the camera assembly. The housing has a thermally conductive hollow body with integral circular and rectangular segments. Sets of thermally conductive ribs 102,102’,103 are on an outer surface of at least one of the segments generally adjacent the heat-generating element. The sets of ribs alternate their respective orientation, lengths and depths defining sets of air guiding channels 104 of alternating lengths and depths from one segment to another. The circular segment of housing may have a first set of thermally conductive ribs protruding radially, defining a first set of air guiding channels of non-uniform cross-sections. The rectangular segment of housing may have a second set of thermally conductive ribs protruding axially, defining a second set of air guiding channels of non-uniform cross-section. The circular segment may have the first set of air guiding channels and the rectangular segment may have the second set of air guiding channels with none of the orientation, depth or length of the first set of air guiding channels being the same as those of the second set of air guiding channels. A process of obtaining this housing includes forging the described features.

Description

Heat dissipation housing The present invention relates to a heat dissipation housing for vehicular camera assembly, most precisely for a surround view camera, and to a manufacturing process thereof.

Next generation of surround view cameras means high performance electronics and optics, having less weight, smaller size, but able to operate in any condition, including high temperatures (even from 85° to 100°C and beyond). As available space for heat dissipation is drastically reduced, thermal management requirements are challenging. In some scenarios, components overheating exceeds some limits and camera shuts down. Prior art that dissipate heat by means of heat sink and fins, as described by the European patent EP 3145755 B1 or US 6667884 Bl, or by means of a combination of air duct and cooling fan, as described by US 2021306538 Al or EP 3918419 Al may not be suitable in a space where each square milimeter counts. However, thermal efficiency leaves room for further improvement.

Technical problem to be solved is to acquire higher heat exchange efficiency at relative small volume by means of a relative simple and inexpensive manufacturing process.

It is an object of the present invention to provide a thermal efficient design of a 25 housing of a camera assembly.

This object is solved by a housing with the features of claim 1.

The dependent claims include advantageous further developments and improvements of the present principles as described below.

According to a first aspect of the invention, there is provided a housing of a vehicular camera assembly for cooling a heat-generating element of the camera assembly, the housing having a thermally conductive hollow body provided with a circular segment integral with a rectangular segment. Sets of thermally conductive ribs are provided on an outer surface of at least one of the segments generally adjacent the heat-generating element, said sets of ribs alternating their respective orientation, lengths and depths and defining sets of air guiding channels of alternating lengths and depths from a segment to another.

By means of this advantageous invention, an enhanced cooling behavior is achieved, combined with a decreased overall weight.

In a preferred embodiment of the present invention, the circular segment is provided with a first set of air guiding channels and the rectangular segment is provided with a second set of air guiding channels, none of orientation, depth or length of the first set of air guiding channels being equal with orientation, depth or length of the second set of air guiding channels.

In a further embodiment of the present invention, only the circular segment of housing is provided with a set of thermally conductive ribs protruding radially, defining a first set of air guiding channels of non-uniform cross-sections.

In a further embodiment of the present invention, only the rectangular segment of housing is provided with a set of thermally conductive ribs protruding axially, defining a second set of air guiding channels of non-uniform cross-section.

According to a second aspect of the invention, there is provided a process of obtaining a housing of a vehicular camera assembly for cooling a heat-generating element of the camera assembly. First, there is provided a thermally conductive hollow body of the housing with a circular segment integral with a rectangular segment. Further, the process comprises forging sets of thermally conductive ribs on an outer surface of at least one of the segments generally adjacent the heat-generating element, said sets of ribs alternating their respective orientation, lengths and depths and defining sets of air guiding channels of alternating lengths and depths from a segment to another.

In one embodiment of the present invention, the process comprises forging a first set of thermally conductive ribs protruding radially from the circular segment of housing, defining a first set of air guiding channels of non-uniform cross-sections.

Forging allows obtaining fine ribs without compromising the housing robustness. Plus, a heat dissipation mechanism is implemented by a cost-efficient process.

In a further embodiment of the present invention, the process comprises forging a second set of thermally conductive ribs protruding axially from the rectangular segment of housing, defining a second set of air guiding channels of non-uniform cross-section. A different number of ribs is forged from a segment to another segment of the housing, and more precisely, the ratio of ribs is 3:4 from the circular segment to rectangular segment.

In a preferred embodiment of the present invention, each set of ribs is forged with different orientation, width, or length.

In a further embodiment of the present invention, the process comprises that additional ribs are forged parallel with the ribs of the second set of ribs, any additional rib being of a shorter length than the length of ribs of second set of ribs.

Further features of the present invention will become apparent from the following description and the appended claims in conjunction with the figures.

Figures Fig. 1 shows an exploded view of a surround view camera from prior art, provided with a housing without heat sink, Fig. 2 presents a top view of a prior art housing from Fig. 1, Fig. 3 shows a section through the housing from Fig. 1 and 2, Fig. 4 shows a heat dissipation housing according to a first embodiment of the invention, Fig. 5 illustrates a section through the housing from Fig. 4, Fig. 6 shows a section view of a heat dissipation housing according to a second embodiment of the invention, Fig. 7 presents a top view of the housing from Fig. 6, Fig. 8 shows a detail from Fig. 7, Fig. 9 shows an isometric of the housing from Fig. 6, Fig. 10 shows a section view of a heat dissipation housing according to a third embodiment of the invention, Fig. 11 presents an isometric view of the housing from Fig. 10, Fig. 12 shows a top view of the housing from Fig. 10.

Detailed description

For a better understanding of the principles of the present invention, embodiments of the invention will be explained in more detail below with reference to the figures. Like reference numerals are used in the figures for the same or equivalent elements and are not necessarily described again for each figure. It is to be understood that the invention is not limited to the illustrated embodiments and that the features described may also be combined or modified without departing from the scope of the invention as defined in the appended claims.

Figure 1 shows an exploded view of a surround view camera SV from prior art.

Surround view camera SV has a housing 1 provided with a central hole h, configured to receive an optical module 2. An intermediary glue layer 3 is provided between housing 1 and optical module 2. A printed circuit board (not illustrated) is a heat-generating element, placed within housing 1.

Figure 2 presents a view of the prior art housing 1 without heat sink. The illustrated housing 1 is a hollow body having a circular segment la integral with a rectangular segment 1 b. In this case, heat dissipation is made exclusively through the housing's material.

Figure 3 shows a section through the prior art housing from Fig. 1. Housing 1 has a lateral wall 12 of a variable thickness w; for example, wall thickness varies from a minimum of 1 mm to a maximum 4 mm, such a geometry ensuring an overall heat dissipation area of 20 cm2.

Figure 4 presents a section view of a first embodiment of a modified housing 10, provided with a heat dissipation mechanism according to invention. Rectangular segment is provided with parallel cooling ribs 100 forged on lateral wall 12, equally spaced apart from each other. Forging as manufacturing process allows obtaining thin cooling ribs 100 of a width w10 of the total thickness of wall, for example 0.4 mm, with a remaining wall thickness w1 (for example, 0.6 mm). Such cooling ribs 100 may extend on a portion where the heat generated by heat-generating element (not illustrated) is maximal, for example on 5:6 of the rectangular segment length. In this design, there are ten vertical cooling ribs 100 provided on each side of rectangular segment, which means a total of 40 cooling ribs 100 -but density may vary. An alternative design (not illustrated) may provide cooling ribs 100 inclined at an angle of more than 30°, the same of each side, or different from one side to another.

Figure 5 shows a top view of the modified housing 10 from Fig. 4. Alongside the cooling ribs 100 air guiding channels 101 are formed, having a depth equal to width w10 of the cooling ribs 100, but a larger width (for example, 1 mm). Both cooling ribs 100 and air guiding channels 101 may have a non-uniform cross-section from base to top, for example each cooling rib may be thinner at top than at base. By adopting such a design, heat dissipation area reaches a total of 23 cm2, therefore an increasing of approx.15% in comparison with a prior art housing without heat sink built in.

Figure 6 shows a second embodiment of a housing 10 modified according to invention. In this case, there are provided alternating cooling ribs 102, 102' of various widths and lengths on wall 12 -for example, some longer cooling ribs 102 have 1.3 mm width (referenced as w11) and alternate with shorter cooling ribs 102' that have 0.5 mm width (referenced as w1). The longer cooling ribs 102 may extend on 5:6 of the rectangular segment length, while shorter cooling ribs 102' may extend only on 3:5 of the longer cooling ribs length (which means half of the rectangular segment length).

Figure 7 shows a top view of the second embodiment, illustrating also corresponding air guiding channels 122. By adopting this design, it is achieved a maximum of heat dissipation surface of 25.5 cm2, therefore an increasing of approx. 30% in comparison with a housing without such built-in heat sink.

Figure 8 shows a detail X from Fig. 7, where the depth of air guiding channels 122 is referred as wl 3. For example, such air channel may start from a lower depth (equal with width w13) of 0.5 mm and reach a higher depth (equal with width w11) of 1.3 mm, the lower depth corresponding to a portion of rectangular segment populated with shorter cooling ribs 102', and the higher depth corresponding to a portion of rectangular segment populated exclusively with longer cooling ribs 102. In fact, by adopting this design, one longer cooling rib 102 on each side of rectangular segment is directly based on the circular segment.

Figure 9 shows an isometric view of the second embodiment from Fig. 7, for a better understanding of the alternance in lengths and widths of the cooling ribs 102 ad 102'. By alternating both widths and lengths of such cooling ribs, which means the corresponding air guiding channels also have alternating depths and lengths, meant to disrupt the air flowing and thus to improve heat transfer.

Figure 10 illustrates a section of a third embodiment of the invention, wherein an additional heat sink may be built by forging cooling ribs 103 on an upper surface of modified housing 10. In this case, cooling ribs 103 are forged as radially protruding ribs, being placed on a circular body of the modified housing 10.

Figure 11 shows an isometric view of the third embodiment from Fig. 10, to illustrate also air guiding channels 104 formed alongside cooling ribs 103. By adopting the additional radial heat sink, a maximum of heat dissipation surface of 27.2 cm2 is achieved, therefore an increasing of approx. 40% in comparison with a housing without such heat sink.

Figure 12 shows a top view of the third embodiment from Fig. 10. In this example, there are provided 30 radial cooling ribs 103, and a corresponding number of air guiding channels 104. Again, the cross-section of air guiding channels 104 is non-uniform.

Even though the process of manufacturing the housing according to the invention is not illustrated by any figure, it comprises forging sets of thermally conductive ribs 100, 102, 103 on an outer surface of at least one of the segments la, lb generally adjacent the heat-generating element (not illustrated). The sets of ribs alternate their respective orientation, lengths and depths and define sets of air guiding channels of alternating lengths and depths from a segment to another.

In an embodiment, the process comprises forging a first set of thermally conductive ribs 103 protruding radially from the circular segment la of housing, defining a first set of air guiding channels 104 of non-uniform cross-sections.

In another embodiment, the process comprises forging a second set of thermally conductive ribs 102 protruding axially from the rectangular segment lb of housing, defining a second set of air guiding channels 101 of non-uniform cross-section.

A peculiarity of the process is that each set of ribs is forged with different orientation, 25 width, or length. Moreover, different number of ribs is forged from one segment la to another segment lb of the housing; for example, there is provided a ratio of ribs of 3:4 from circular segment la to rectangular segment 1 b.

In another embodiment, additional ribs 102' are forged parallel with the ribs 102 of the second set of ribs, any additional rib 102' being of a shorter length than the length of ribs 102 of second set of ribs.

Main point regarding the inventive concept presented here is to create a combination of sets of cooling ribs and air guiding channels in an alternance able to enhance the heat transfer area and to simultaneously disrupt the air flowing in the air guiding channels. By combining any of these sets of cooling ribs on the same housing (even such an exemplary embodiment is not illustrated), it is possible to increase the heat dissipation surface up to 70% and beyond.

However, while certain embodiments of the present invention have been described in detail, those familiar with the art to which this invention relates will recognize various alternative designs and embodiments for practicing the invention as defined by the following claims.

List of reference numbers SV surround view camera

1 Prior art housing

2 Optical module 3 Glue layer Heat dissipation housing 100, 102, 102', 103 -Cooling rib 101, 104, 122-Air guiding channel 12 Housing wall la Circular segment lb Rectangular segment h Central hole w, wl, w10, wl 1, w12, w13 -Width

Claims

Patent claims 1. A housing of a vehicular camera assembly for cooling a heat-generating element of the camera assembly, the housing having a thermally conductive hollow body provided with a circular segment integral with a rectangular segment, characterized in that sets of thermally conductive ribs are provided on an outer surface of at least one of the segments generally adjacent the heat-generating element, said sets of ribs alternating their respective orientation, lengths and depths and defining sets of air guiding channels of alternating lengths and depths from a segment to another.
2. Housing according to claim 1, characterized in that the circular segment of housing is provided with a first set of thermally conductive ribs protruding radially, defining a first set of air guiding channels of non-uniform cross-sections.
3. Housing according to claim 1, characterized in that the rectangular segment of housing is provided with a second set of thermally conductive ribs protruding axially, defining a second set of air guiding channels of non-uniform cross-section.
4. Housing according to preceding claims, characterized in that the circular segment is provided with the first set of air guiding channels and the rectangular segment is provided with the second set of air guiding channels, none of orientation, depth, or length of the first set of air guiding channels being the same orientation, depth, or length of the second set of air guiding channels.
5. Housing according to any of the preceding claims, characterized in that the number of ribs from the first set of ribs is different from the number of ribs from the second set of ribs, and more precisely, the ratio of ribs of first set is 3:4 from the ribs of second set.
6. Housing according to claims 1 and 3, ch a r a cterized in that each rib from the second set is extending partially on rectangular segment length, more precisely on a ratio of 5:6 of the rectangular segment length.
7. Housing according to preceding claim, characterized in that in each air guiding channel from the second set is provided with an additional rib parallel with the ribs of the second set of ribs, any additional rib being of a shorter length than the length of ribs of second set of ribs.
8. Housing according to any preceding claims, ch a r acter i ze d in that most of the ribs are thinner at top than at base.
9. Housing according to any preceding claims, ch a r a cte r iz ed i n that all the ribs are manufactured by a forging process. 15
10. A process of obtaining a housing of a vehicular camera assembly for cooling a heat-generating element of the camera assembly, providing a thermally conductive hollow body of the housing with a circular segment integral with a rectangular segment, ch a r a cterized i n that it further comprises forging sets of thermally conductive ribs on an outer surface of at least one of the segments generally adjacent the heat-generating element, said sets of ribs alternating their respective orientation, lengths and depths and defining sets of air guiding channels of alternating lengths and depths from one segment to another.
11. Process according to claim 10, characterized i n that the process comprises forging a first set of thermally conductive ribs protruding radially from the circular segment of housing, defining a first set of air guiding channels of non-uniform cross-sections.
12. Process according to claim 10, characterized i n that the process comprises forging a second set of thermally conductive ribs protruding axially from the rectangular segment of housing, defining a second set of air guiding channels of non-uniform cross-section.
13. Process according to claim 10, characterized in that each set of ribs is forged with different orientation, width, or length, from one segment to another.
14. Process according to claim 1Q characterized in that a dtiferent number of ribs is forged from one segment to another segment of the housing, and more precisely, there is provided a ratio of 3:4 ribs from the circular segment to rectangular segment.
15. Process according to claim 10, characterized in that additional ribs are forged parallel with the ribs of the second set of ribs, any additional rib being of a shorter length than the length of ribs of second set of ribs.