Vapor chamber and manufacturing method of vapor chamber
A vapor chamber which enables to raise the heat transfer coefficient by improving the transport efficiency of the working fluid, and a manufacturing method thereof. A vapor chamber includes a working fluid in a sealed internal space formed by joining a first metal sheet and a second metal sheet, in which in an opposite surface of at least one metal sheet (at least opposite surface 12 a in FIGS. 1 A and 1 B) among opposite surfaces 11 a, 12 a at which the first metal sheet and the second metal sheet are facing each other, main grooves extending continuously or discontinuously towards one direction (extending direction X of main groove) are formed in line at a predetermined interval, and connection grooves connecting main grooves 21 a, 21 b which are adjacent are formed at irregular arrangement pitches and irregular grooves widths toward a different direction than the one direction (extending direction X of main groove 21 ).
1 . A vapor chamber comprising a working fluid in a sealed internal space formed by joining a first metal sheet and a second metal sheet,
wherein, in an opposite surface of at least one metal sheet of the first metal sheet and the second metal sheet, among opposite surfaces at which the first metal sheet and the second metal sheet are facing each other,
main grooves extending continuously or discontinuously towards one direction are formed in line at a predetermined interval, and connection grooves connecting main grooves which are adjacent are formed at irregular arrangement pitches and irregular grooves widths toward a different direction than the one direction,
the connection grooves are such that angles relative to a direction in which the main grooves extend differ,
the irregular arrangement pitches are such that, for all of the connection grooves present within an area of 10 mm height×10 mm width on the surface where the connection grooves are formed, when an arrangement pitch between adjacent connection grooves is determined by an average of both ends, a standard deviation of the arrangement pitches is at least 10% relative to an average value of the arrangement pitches, and
the irregular grooves widths are such that, for all of the connection grooves present within an area of 10 mm height×10 mm width on the surface where the connection grooves are formed, when groove width dimensions are determined, a standard deviation of determined groove width dimensions is at least 10% relative to an average value of the determined groove width dimensions.
2 . The vapor chamber according to claim 1 , further comprising an evaporator which evaporates the working fluid, and a condenser arranged at a position separated from the evaporator and which condenses the working fluid,
wherein at least part of the main grooves configure a flow channel in which the working fluid of liquid phase refluxes from the condenser toward the evaporator, and
wherein the internal space configures a flow channel of the working fluid of gas phase from the evaporator toward the condenser.
3 . The vapor chamber according to claim 1 , wherein an opposite surface of the first metal sheet has a recess partitioning to form the internal space,
wherein the second metal sheet is a flat shape at least at the evaporator, and
wherein the main grooves are arranged in line at least in an opposite surface of the second metal sheet.
4 . The vapor chamber according to claim 1 , wherein the main grooves have a larger groove depth dimension than groove width dimension.
5 . The vapor chamber according to claim 1 , wherein a micro-uneven surface having unevenness of a dimension smaller than a groove depth dimension of the main grooves are further formed in an inner surface of the main grooves, and on a portion of the opposite surface of the at least one metal sheet demarcated by the main groove and the connection groove.
6 . The vapor chamber according to claim 1 , wherein the main grooves have an arrangement pitch in a range of at least 100 μm and no more than 250 μm.
7 . The vapor chamber according to claim 1 , wherein the main grooves have a groove width in a range of at least 10 μm and no more than 100 μm, and
wherein the main grooves have a groove depth in a range of at least 10 μm and no more than 1000 μm.
8 . The vapor chamber according to claim 1 , wherein the connection grooves have a groove width in a range of at least 5 μm and no more than 100 μm, and
wherein the connection grooves have a groove depth in a range of at least 10 μm and no more than 1000 μm.
9 . The vapor chamber according to claim 1 , wherein the internal space is partitioned into a plurality of vapor flow channels by contact between abutting parts provided in the opposite surfaces of each of the first metal sheet and the second metal sheet, and
wherein the main grooves and the connection grooves are arranged in a region at least including the abutting part of the opposite surface of the at least one metal sheet.
10 . A manufacturing method of the vapor chamber according to claim 1 , the method comprising forming the main grooves and the connection grooves by irradiating a laser beam so as to draw a line in one direction onto the opposite surface of the at least one metal sheet.
11 . The vapor chamber according to claim 2 , wherein an opposite surface of the first metal sheet has a recess partitioning to form the internal space,
wherein the second metal sheet is a flat shape at least at the evaporator, and
wherein the main grooves are arranged in line at least in an opposite surface of the second metal sheet.
12 . The vapor chamber according to claim 2 , wherein the main grooves have a larger groove depth dimension than groove width dimension.
13 . The vapor chamber according to claim 2 , wherein a micro-uneven surface having unevenness of a dimension smaller than a groove depth dimension of the main grooves are further formed in an inner surface of the main groove, and a portion of the opposite surface of the at least one metal sheet demarcated by the main groove and the connection groove.
14 . The vapor chamber according to claim 2 , wherein the main grooves have an arrangement pitch in a range of at least 100 μm and no more than 250 μm.
15 . The vapor chamber according to claim 2 , wherein the main grooves have a groove width in a range of at least 10 μm and no more than 100 μm, and
wherein the main grooves have a groove depth in a range of at least 10 μm and no more than 1000 μm.
16 . The vapor chamber according to claim 2 , wherein the connection grooves have a groove width in a range of at least 5 μm and no more than 100 μm, and
wherein the connection grooves have a groove depth in a range of at least 10 μm and no more than 1000 μm.
17 . The vapor chamber according to claim 2 , wherein the internal space is partitioned into a plurality of vapor flow channels by contact between abutting parts provided in the opposite surfaces of each of the first metal sheet and the second metal sheet, and
wherein the main grooves and the connection grooves are arranged in a region at least including the abutting part of the opposite surface of the at least one metal sheet.
18 . A manufacturing method of the vapor chamber according to claim 2 , the method comprising forming the main grooves and the connection grooves by irradiating a laser beam so as to draw a line in one direction onto the opposite surface of the at least one metal sheet.
19 . The vapor chamber according to claim 3 , wherein the main grooves have a larger groove depth dimension than groove width dimension.
20 . The vapor chamber according to claim 3 , wherein a micro-uneven surface having unevenness of a dimension smaller than a groove depth dimension of the main grooves have further formed in an inner surface of the main grooves, and on a portion of the opposite surface of the at least one metal sheet demarcated by the main grooves and the connection grooves.