A VAPOR CHAMBER

Abstract

This invention relates to a vapor chamber (100) comprising a first thermally conductive plate (110) and a second thermally conductive plate (120) separated from each other by a plurality of bridging elements (140) to form a cavity (130) having a first height, H1 (001). The vapor chamber (100) comprises a bending section (151) and a non-bending section (152). The bending section (151) is configured to provide a bend having a first volume fraction (V1) of bridging elements (140), and the non-bending section (152) having a second volume fraction (V2) of bridging elements (140). A ratio of the first volume fraction (V1) and the second volume fraction (V2) is less than 0.7.

Claims

1. A vapor chamber comprising: a first thermally conductive plate and a second thermally conductive plate separated from each other by a plurality of bridging elements to form a chamber having a first height, H1, wherein the vapor chamber having a length L along a longitudinal axis and a width W defined perpendicular to the longitudinal axis and comprises a bending section configured to provide a bend around an axis in a direction parallel with the width W, said vapor chamber further having a first volume fraction of bridging elements, and a non-bending section having a second volume fraction of bridging elements, and wherein a ratio of the first volume fraction and the second volume fraction is less than 0.7.

2. The vapor chamber according to claim 1, wherein the ratio of the first volume fraction and the second volume fraction is selected from a range between 0 and 0.3.

3. The vapor chamber according to claim 1, wherein a ratio of the length, L and the width, W is selected from a range between 0.2 and 5.

4. The vapor chamber according to claim 1, wherein the width, W varies along the longitudinal axis from a first width value to a second width value, and wherein the second width value is selected from a range between 0.1 times of the first width value to 5 times of the first width value.

5. The vapor chamber according to claim 4, wherein the width, W varies along the longitudinal axis from a first width value to a second width value and a relation between the width, W along the longitudinal axis is defined by a linear function or a step function.

6. The vapor chamber according to claim 1, wherein the vapor chamber comprises an n number of the bending sections, and an (n?1), n or (n+1) number of the non-bending sections, wherein n is selected from a range between 2 to 20, and wherein the non-bending sections and the bending sections are arranged alternately.

7. The vapor chamber according to claim 1, wherein the vapor chamber has a thickness, d.sub.e, wherein the bending section is configured to provide a bend having a bending angle, ?, a bending radius, r.sub.b, and a bending length, L.sub.b along the longitudinal axis, and wherein the bending length, L.sub.b is greater than or equal to ?*(r.sub.b+d.sub.e)/(360/?).

8. The vapor chamber according to claim 7, wherein the bending radius, r.sub.b that is less than or equal to 3 mm.

9. The vapor chamber according to claim 1, wherein the bending angle, ? is selected from a range between 45 degrees and 135 degrees.

10. The vapor chamber according to claim 1, wherein the chamber comprises a wick structure, wherein the wick structure comprises a first wick structure attached to an inner surface of the first thermally conductive plate facing the chamber and a second wick structure attached to an inner surface of the second thermally conductive plate facing the chamber.

11. The vapor chamber according to claim 1, wherein the plurality of bridging elements comprise columns.

12. A method for providing a bent vapor chamber, the method comprising: providing a vapor chamber along the longitudinal axis according to claim 1; filling the bent vapor chamber with a coolant; and sealing the bent vapor chamber.

13. The method according to claim 12, wherein the method comprises bending along the bending section is to provide the bent vapor chamber having meandering shapes.

14. A device comprising the bent vapor chamber obtained with the method according to claim 12, wherein the device further comprises an electronic component thermally coupled to the bent vapor chamber.

15. The device according to claim 14, wherein the electronic component comprises one or more light-emitting devices.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0108] The above, as well as additional objects, features, and advantages of the disclosed devices, methods, and systems, will be better understood through the following illustrative and non-limiting detailed description of embodiments of devices, methods, and systems, with reference to the appended drawings, in which:

[0109] FIG. 1 shows a perspective cross-sectional view of a vapor chamber:

[0110] FIGS. 2(a) and (b) schematically depict cross-sectional views of a bent vapor chamber and a bent section of the bent vapor chamber as shown in FIG. 2(a), respectively:

[0111] FIGS. 3(a) to (d) schematically depict a vapor chamber with varying width in the longitudinal axis, a front view of a bent vapor chamber, a cross-section view of the bent vapor chamber, and a side view of the bent vapor chamber, respectively:

[0112] FIG. 4 schematically depicts an alternative vapor chamber with varying width in the longitudinal axis, similar to FIG. 3(a):

[0113] FIGS. 5(a) to (d) schematically depict an alternative vapor chamber with varying width in the longitudinal axis, a front view of a bent vapor chamber, a cross-section view of the bent vapor chamber, and a side view of the bent vapor chamber, respectively:

[0114] FIG. 6 schematically depicts an alternative vapor chamber with varying width in the longitudinal axis, similar to FIG. 5(a):

[0115] FIGS. 7(a) and (b) schematically depict an alternative vapor chamber similar to FIG. 5(a) with an opening through the bending section and a yet another vapor chamber having a foldable stud associated with the bending section:

[0116] FIG. 8 schematically depicts a method for producing a bent vapor chamber; and

[0117] FIG. 9 schematically depicts a device having a bent vapor chamber.

[0118] As illustrated in the figures, the sizes of layers and regions are exaggerated for illustrative purposes and, thus, are provided to illustrate the general structures of embodiments of the present invention. Like reference numerals refer to like elements throughout.

DETAILED DESCRIPTION OF THE EMBODIMENTS

[0119] The present invention will now be described more fully hereinafter with reference to the accompanying drawings, in which currently preferred embodiments of the invention are shown. This invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein: rather, these embodiments are provided for thoroughness and completeness, and fully convey the scope of the invention to the skilled person.

[0120] FIG. 1 schematically depicts a perspective cross-sectional view of a vapor chamber 100. The vapor chamber 100 has a length 002 (L) along a longitudinal axis 005 and a width 003 (W) defined perpendicular to the longitudinal axis 005. In this figure, the vapor chamber 100 comprises a first thermally conductive plate 110 and a second thermally conductive plate 120 with a chamber 130 in between. The height or thickness 004 (d.sub.e) of the vapor chamber 100 is the distance between a first outer surface 011 of the first thermally conductive plate 110 and a second outer surface 022 of the second thermally conductive plate 120. The first thermally conductive plate 110 has a first thickness 112 (d.sub.1) and the second thermally conductive plate 120 has a second thickness 122 (d.sub.1).

[0121] The chamber 001 comprises a wick structure. The wick structure comprises a first wick structure 111 attached to a first inner surface 013 of the first thermally conductive plate 110 facing the chamber 130. Similarly, a second wick structure 121 attached to a second inner surface 012 of the second thermally conductive plate 120 facing the chamber 130. The chamber 130 has a first height 001 (H1). The vapor chamber element 100 further comprises bridging elements 140 bridging at least part of the first height 001 (H1). The edge surfaces 016 of the vapor chamber 100 can be sealed as shown in FIG. 1.

[0122] The vapor chamber 100 further comprises a plurality of sections 150 configured along the longitudinal axis 005. In the depicted embodiment, the plurality of sections 150 comprise a bending section 151 having a first volume fraction V.sub.1 of bridging elements 140. The plurality of sections further comprises a non-bending section 152 having a second volume fraction V.sub.2 of bridging elements 140, especially wherein the bending section 151 is configured (directly) between two non-bending section sections 151, i.e., the bending section 151 may border two non-bending sections 152. The bending section 151 is configured to provide a bend at the middle of the bending section 006. FIG. 1 depicts that the first volume fraction V.sub.1 of bridging elements 140 in the bending section 151 is less compared to the second volume fraction V.sub.2 of bridging elements 140 in the non-bending section 152. The volume fraction V.sub.1 of bridging elements 140 in the bending section 151 may be zero or none when compared to the non-bending section 152. This may allow bending with a small bending radius and easy bending of the bending section without rapturing the vapor chamber.

[0123] A ratio of the first volume fraction V.sub.1 and the second volume fraction V.sub.2 can be less than 1. The ratio of the first volume fraction V.sub.1 and the second volume fraction V.sub.2 may also be selected from a range between 0 and 0.5.

[0124] In FIG. 1, the bridging elements 140 comprise columns, especially columns having a shape selected from the group consisting of a sphere, a plate, and a cylinder, such as especially spherical columns.

[0125] The vapor chamber 100, especially the chamber 130, may comprise a wick structure 111, 121. The wick structure may especially comprise the first wick structure 111 associated with the first thermally conductive plate 110 and the second wick structure 121 associated with the second thermally conductive plate 120.

[0126] The bridging elements 140 may be at least partly comprised by the first and the second wick structures 111, 121.

[0127] The vapor chamber 100 shown in FIG. 1 comprises bending sections 151 that can be configured to provide bent vapor chamber 200 as shown in FIG. 2. Therefore, FIG. 1 depicts the vapor chamber element 100 before bending. FIG. 2 schematically depicts the vapor chamber element 100 after bending at the bending sections 151. FIG. 2(a) schematically depicts a cross-sectional view of a bent vapor chamber 200. The vapor chamber 100 as shown in FIG. 1 may comprise a plurality of bending sections 151, especially an n bending sections 151, especially wherein n is selected from the range of 2 to 10, such as from the range of 2 to 4. In FIG. 2(a), n=4. Similarly, the vapor chamber 100 may have an (n?1) or (n+1) non-bending sections 152. In FIG. 2(a), the bent vapor chamber 200 comprises (n+1)=5 non-bending sections 152. The bent vapor chamber 200 has a constant thickness 004. However, the width (W) may vary along the longitudinal axis 005 of the vapor chamber 100. The vapor chamber 100 is bent at a bending angle 080 (?) which is approximately 90 degrees. The bending section has a bending length 009 (L.sub.s).

[0128] The first thermally conductive plate 110 and the second thermally conductive plate 120 may have (respectively) a first thickness 112 (d.sub.1) and a second thickness 122 (d.sub.2) independently selected from the range of 50-5000 ?m.

[0129] FIG. 2(b) shows one of the bent sections of the bent vapor chamber 200 as shown in FIG. 2(a). The bending section 151 has a bending radius r.sub.b, especially an inner bending radius 014 (r.sub.i), or especially an outer bending radius 015 (r.sub.o). The bending radius, r.sub.b can be the inner bending radius 014 (r.sub.i), or the outer bending radius 015 (r.sub.o), or an average of the inner bending radius 014 (r.sub.i), and the outer bending radius 015 (r.sub.o). The bending radius, r.sub.b can be less than or equal to 3 mm. The inner bending radius 014 (r.sub.i) is smaller than the outer bending radius 015 (r.sub.o) and the difference between the inner bending radius 014 (r.sub.i), and the outer bending radius 015 (r.sub.o) depending on the thickness 004 (d.sub.s) of the vapor chamber 100.

[0130] In FIG. 2(b), the bent vapor chamber 200 has a thickness 004 (d.sub.s). The element thickness 004 (d.sub.s) is essentially the sum of the first height 001 (H1), the first thickness 112 (d.sub.1) and the second thickness 122 (d.sub.2). The bending section 151 has a bending length 009 (L.sub.b). In particular, the bending section 151 comprises a bending subsection 151 having a bending subsection length 008 (L.sub.bs) and two support subsections length 007 (L.sub.ss). Therefore, bending length 009 (L.sub.b)=the bending subsection length 008 (L.sub.bs)+2*the support subsections length 007 (L.sub.ss). The bending subsection length 008 (L.sub.bs) may especially be ?*(r.sub.b+d.sub.e)/(360/?). The support subsection length 007 (L.sub.ss) can be 3*d.sub.e to 20*d.sub.e, such as from the range of 5*d.sub.e to 10*d.sub.e. Hence, the bending length 009 (L.sub.b) may especially be at least ?*(r.sub.b+d)/(360/?)+2*3*d.sub.e, such as ?*(r.sub.b+d.sub.e)/(360/?)+2*5*d.sub.e. Alternatively, the bending length 009 (L.sub.b) may especially be selected from the range of ?*(r.sub.b+d.sub.e)/(360/?)+2*3*d.sub.e to ?*(r.sub.b+d.sub.e)/(360/?)+2*20*d.sub.e, or especially from the range of ?*(r.sub.b+d.sub.e)/(360/?)+2*5*d.sub.e to ?*(r.sub.b+d.sub.e)/(360/?)+2*10*d.sub.e.

[0131] The bending section 151 may have a bending length 009 (L.sub.b) along the longitudinal axis 005, especially wherein the bending length 009, L.sub.b? 0.5 mm.

[0132] In FIG. 3(a) the vapor chamber 100 is depicted in a top view of the device and in an unbent condition. The vapor chamber 100 has bending sections with the middle of the bending sections 006 indicated in the figure. The vapor chamber 100 has rectangular cells 088 in between the middle of the bending sections 006. The width 003 (W) varies along the longitudinal axis 005 from a first width value W.sub.1 to a second width value W.sub.2. The relation between the width 003 (W) along the longitudinal axis 005 can be defined by a step function. Such a vapor chamber 100 can be configured in to a bent vapor chamber 200 with meandering shapes. FIG. 3(b) to (d) schematically depict a bent vapor chamber 200 obtained from folding or bending the vapor chamber 100 in FIG. 3(a) in a front view, a cross-section view; and a side view, respectively.

[0133] FIG. 4 schematically depicts a vapor chamber 100 with varying width 003 (W) in the longitudinal axis 005, similar to FIG. 3(a). However, the width 003 (W) varies from the first width value W.sub.1 to the second width value W.sub.2 in discrete step values that are random, while in FIG. 3(a) the first width value W.sub.1 varies to the second width value W.sub.2 gradually towards the middle and then decreases towards the end.

[0134] In FIG. 5(a), the vapor chamber 100 has hexagonal cells 088 in between the middle of the bending sections 006. The width 003 (W) varies from the first width value W.sub.1 to the second width value W.sub.2 linearly within each cell 088. Each cell 088 is adjoined by neighboring cells 088 by straight sections. FIG. 5(b) to (d) schematically depict an alternative vapor chamber with varying width in the longitudinal axis, a front view of the vapor chamber, a cross-section view of the vapor chamber, and a side view of the vapor chamber, respectively. Such a vapor chamber 100 can be configured into a bent vapor chamber 200 with meandering shapes. FIG. 5(b) to (d) schematically depict a bent vapor chamber 200 obtained from folding or bending the vapor chamber 100 in FIG. 5(a) in a front view, a cross-section view, and a side view, respectively.

[0135] FIG. 6 schematically depicts an alternative vapor chamber 100 with varying width 003 (W) in the longitudinal axis 005, similar to FIG. 5(a). In this case, the hexagonal cell 088 sizes gradually increase towards the middle of the vapor chamber 100.

[0136] FIGS. 7(a) schematically depicts an alternative vapor chamber 100 similar to FIG. 5(a), except with openings 089 located in the middle of the bending sections 006. For folding or bending an unbent vapor chamber, an opening in the bending section with less or no bridging element compared to a non-bending section may allow easier bending with a small bending radius.

[0137] In FIG. 7(b), a vapor chamber 100 is depicted to have a foldable stud 090 associated with the middle of the bending section 006. Such a foldable stud 090 may allow easy mechanical fixation of a vapor chamber 100 with a device.

[0138] FIG. 8 schematically depicts a method 300 for producing a bent vapor chamber 200 from a vapor chamber 100 that is flat across a longitudinal axis 005 as shown in previous figures. The method 300 may start with providing 301 a vapor chamber 100 along the longitudinal axis 005. Then, bending 302 the vapor chamber 100 along the bending section 151 or in the middle of the bending section 006. Subsequently, filling 303 the bent vapor chamber 200 with a coolant in the form of a liquid or gas. Finally, sealing 304 the bent vapor chamber 200.

[0139] FIG. 9 schematically depicts a device 400 having a bent vapor chamber 200 obtainable with the method 300 described above. The device 200 further comprises an electronic component 410 that comprises one or more light-emitting devices 420 and the electronic component 410 is thermally coupled to the bent vapor chamber 200. The one or more light-emitting devices 420 may comprise one or more solid-state light sources (such as a LED or laser diode). The electronic component or the device may further comprise one or more driver unit and therefore, the device may comprise one or more bent vapor chambers for providing cooling of the driver unit. The device 400 is part of a lighting device 500 that further comprises a housing 401 and a fitting 402 for providing mechanical and electrical connection with a complementary socket. Therefore, the lighting device 500 can form a luminaire. The bent vapor chamber 200 is arranged to provide cooling for the electronic component 410 in such a scenario.

[0140] The term plurality. refers to two or more. Furthermore, the terms a plurality of and a number of may be used interchangeably.

[0141] The terms substantially or essentially herein, and similar terms will be understood by the person skilled in the art. The terms substantially or essentially may also include embodiments with entirely, completely, all, etc. Hence, in embodiments, the adjective substantially or essentially may also be removed. Where applicable, the term substantially or the term essentially may also relate to 90% or higher, such as 95% or higher, especially 99% or higher, even more especially 99.5% or higher, including 100%. Moreover, the terms about and approximately may also relate to 90% or higher, such as 95% or higher, especially 99% or higher, even more especially 99.5% or higher, including 100%. For numerical values it is to be understood that the terms substantially, essentially, about, and approximately may also relate to the range of 90%-110%, such as 95%-105%, especially 99%-101% of the values(s) it refers to.

[0142] The term comprise also includes embodiments wherein the term comprises means consists of.

[0143] The term and/or especially relates to one or more of the items mentioned before and after and/or. For instance, a phrase item 1 and/or item 2 and similar phrases may relate to one or more of item 1 and item 2. The term comprising may in an embodiment refer to consisting of but may in another embodiment also refer to containing at least the defined species and optionally one or more other species.

[0144] Furthermore, the terms first, second, third and the like in the description and in the claims, are used for distinguishing between similar elements and not necessarily for describing a sequential or chronological order. It is to be understood that the terms so used are interchangeable under appropriate circumstances and that the embodiments of the invention described herein are capable of operation in other sequences than described or illustrated herein.

[0145] The devices, apparatus, or systems may herein amongst others be described during operation. As will be clear to the person skilled in the art, the invention is not limited to methods of operation, or devices, apparatus, or systems in operation.

[0146] The term further embodiment and similar terms may refer to an embodiment comprising the features of the previously discussed embodiment, but may also refer to an alternative embodiment.

[0147] It should be noted that the above-mentioned embodiments illustrate rather than limit the invention, and that those skilled in the art will be able to design many alternative embodiments without departing from the scope of the appended claims.

[0148] In the claims, any reference signs placed between parentheses shall not be construed as limiting the claim.

[0149] Use of the verb to comprise and its conjugations does not exclude the presence of elements or steps other than those stated in a claim. Unless the context clearly requires otherwise, throughout the description and the claims, the words comprise, comprising, include, including, contain, containing and the like are to be construed in an inclusive sense as opposed to an exclusive or exhaustive sense: that is to say, in the sense of including, but not limited to.

[0150] The article a or an preceding an element does not exclude the presence of a plurality of such elements.

[0151] The invention may be implemented by means of hardware comprising several distinct elements, and by means of a suitably programmed computer. In a device claim, or an apparatus claim, or a system claim, enumerating several means, several of these means may be embodied by one and the same item of hardware. The mere fact that certain measures are recited in mutually different dependent claims does not indicate that a combination of these measures cannot be used to advantage.

[0152] The invention also provides a control system that may control the device, apparatus, or system, or that may execute the herein described method or process. Yet further, the invention also provides a computer program product, when running on a computer which is functionally coupled to or comprised by the device, apparatus, or system, controls one or more controllable elements of such device, apparatus, or system.

[0153] The invention further applies to a device, apparatus, or system comprising one or more of the characterizing features described in the description and/or shown in the attached drawings. The invention further pertains to a method or process comprising one or more of the characterizing features described in the description and/or shown in the attached drawings. Moreover, if a method or an embodiment of the method is described being executed in a device, apparatus, or system, it will be understood that the device, apparatus, or system is suitable for or configured for (executing) the method or the embodiment of the method respectively.

[0154] The various aspects discussed in this patent can be combined in order to provide additional advantages. Further, the person skilled in the art will understand that embodiments can be combined, and that also more than two embodiments can be combined. Furthermore, some of the features can form the basis for one or more divisional applications.