CN216011895U - Micro-deformation enhanced heat conduction contact phase change heat transfer device - Google Patents
Micro-deformation enhanced heat conduction contact phase change heat transfer device Download PDFInfo
- Publication number
- CN216011895U CN216011895U CN202122388457.2U CN202122388457U CN216011895U CN 216011895 U CN216011895 U CN 216011895U CN 202122388457 U CN202122388457 U CN 202122388457U CN 216011895 U CN216011895 U CN 216011895U
- Authority
- CN
- China
- Prior art keywords
- micro
- deformation
- side wall
- phase change
- transfer device
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
- 230000008859 change Effects 0.000 title claims abstract description 30
- 239000000758 substrate Substances 0.000 claims abstract description 47
- 239000007788 liquid Substances 0.000 claims abstract description 20
- 230000007246 mechanism Effects 0.000 claims abstract description 15
- 238000009434 installation Methods 0.000 claims abstract description 12
- 230000009471 action Effects 0.000 claims abstract description 7
- RYGMFSIKBFXOCR-UHFFFAOYSA-N Copper Chemical compound [Cu] RYGMFSIKBFXOCR-UHFFFAOYSA-N 0.000 claims description 7
- 229910052802 copper Inorganic materials 0.000 claims description 7
- 239000010949 copper Substances 0.000 claims description 7
- 229910052782 aluminium Inorganic materials 0.000 claims description 5
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 claims description 5
- 239000002861 polymer material Substances 0.000 claims description 5
- 229920000620 organic polymer Polymers 0.000 claims description 4
- 125000004122 cyclic group Chemical group 0.000 claims description 2
- 238000000034 method Methods 0.000 abstract description 10
- 230000008569 process Effects 0.000 abstract description 10
- 230000001105 regulatory effect Effects 0.000 abstract description 7
- 238000010292 electrical insulation Methods 0.000 abstract description 2
- 239000000463 material Substances 0.000 description 8
- 238000010586 diagram Methods 0.000 description 4
- 229910052751 metal Inorganic materials 0.000 description 4
- 239000002184 metal Substances 0.000 description 4
- 230000017525 heat dissipation Effects 0.000 description 3
- CSCPPACGZOOCGX-UHFFFAOYSA-N Acetone Chemical compound CC(C)=O CSCPPACGZOOCGX-UHFFFAOYSA-N 0.000 description 2
- 230000006835 compression Effects 0.000 description 2
- 238000007906 compression Methods 0.000 description 2
- 239000008367 deionised water Substances 0.000 description 2
- 229910021641 deionized water Inorganic materials 0.000 description 2
- 230000000694 effects Effects 0.000 description 2
- 238000005516 engineering process Methods 0.000 description 2
- 230000004907 flux Effects 0.000 description 2
- 239000007789 gas Substances 0.000 description 2
- 238000009413 insulation Methods 0.000 description 2
- 238000010030 laminating Methods 0.000 description 2
- 230000035882 stress Effects 0.000 description 2
- 239000000126 substance Substances 0.000 description 2
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Chemical compound O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 2
- 229910000838 Al alloy Inorganic materials 0.000 description 1
- 229920000049 Carbon (fiber) Polymers 0.000 description 1
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N Silicium dioxide Chemical compound O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 description 1
- 230000032683 aging Effects 0.000 description 1
- 229910045601 alloy Inorganic materials 0.000 description 1
- 239000000956 alloy Substances 0.000 description 1
- 230000033228 biological regulation Effects 0.000 description 1
- 230000005540 biological transmission Effects 0.000 description 1
- 239000004917 carbon fiber Substances 0.000 description 1
- 230000018109 developmental process Effects 0.000 description 1
- 230000005489 elastic deformation Effects 0.000 description 1
- 229920001971 elastomer Polymers 0.000 description 1
- 239000000835 fiber Substances 0.000 description 1
- 230000007774 longterm Effects 0.000 description 1
- 150000002739 metals Chemical class 0.000 description 1
- VNWKTOKETHGBQD-UHFFFAOYSA-N methane Chemical compound C VNWKTOKETHGBQD-UHFFFAOYSA-N 0.000 description 1
- 238000004377 microelectronic Methods 0.000 description 1
- 238000004806 packaging method and process Methods 0.000 description 1
- 239000002245 particle Substances 0.000 description 1
- 238000005215 recombination Methods 0.000 description 1
- 230000009467 reduction Effects 0.000 description 1
- 230000003014 reinforcing effect Effects 0.000 description 1
- 239000011347 resin Substances 0.000 description 1
- 229920005989 resin Polymers 0.000 description 1
- 230000004044 response Effects 0.000 description 1
- 229920006395 saturated elastomer Polymers 0.000 description 1
- 230000035939 shock Effects 0.000 description 1
- 239000000741 silica gel Substances 0.000 description 1
- 229910002027 silica gel Inorganic materials 0.000 description 1
- 229910052710 silicon Inorganic materials 0.000 description 1
- 239000010703 silicon Substances 0.000 description 1
- 238000004088 simulation Methods 0.000 description 1
- 239000011343 solid material Substances 0.000 description 1
- 239000010935 stainless steel Substances 0.000 description 1
- 229910001220 stainless steel Inorganic materials 0.000 description 1
- 230000001360 synchronised effect Effects 0.000 description 1
- 230000008646 thermal stress Effects 0.000 description 1
- 230000007704 transition Effects 0.000 description 1
- 239000002918 waste heat Substances 0.000 description 1
Images
Landscapes
- Cooling Or The Like Of Semiconductors Or Solid State Devices (AREA)
Abstract
The invention discloses a micro-deformation enhanced heat conduction contact phase change heat transfer device which comprises an upper substrate, a lower substrate, a micro-deformation side wall, a liquid charging pipe, a pressure adjusting mechanism, a wire mesh capillary core and a working medium. The upper and lower substrates, the micro-deformation side wall and the liquid filling pipe are welded to form a cavity, the pressure regulating mechanism is communicated with the cavity, the wire mesh capillary cores are laid on the inner sides of the upper substrate part and the lower substrate part of the cavity, and the cavity is filled with working medium through the liquid filling pipe. When the heat exchanger is used, the lower substrate is attached to the cold end, the upper substrate is attached to the hot end, the micro-deformation side wall can deform under the action of installation pressure, and heat is transmitted from the hot end to the cold end by means of working medium circulation flowing phase change. The invention provides a micro-deformation enhanced heat conduction contact phase change heat transfer device which is suitable for the distance change of a cold end and a hot end in the installation and use processes, applies pretightening force, can realize electrical insulation between cold sources and hot sources, strengthens the backflow of a liquid working medium, and relieves the pressure impact of an upper substrate and a lower substrate on an electronic component in the installation and use processes.
Description
Technical Field
The invention relates to the technical field of electronic equipment thermal management.
Background
Along with the rapid development of microelectronic technology, the performance of electronic equipment is rapidly increased, but limited by the efficiency of electronic devices, nearly 80% of electric power is converted into waste heat, if the heat of the electronic equipment cannot be effectively dissipated, the performance and the service life of the electronic equipment are seriously affected, and the importance of thermal management of the electronic equipment is increasingly highlighted. From the heat transfer path, the heat generated in the electronic device is firstly diffused to the packaging shell and then is transferred to the heat sinks such as the cold plate and the radiator by the shell, data shows that the heat transfer resistance between the shell and the heat sink accounts for the highest heat transfer resistance in the whole process, and the proper heat transfer resistance control has important significance on the reliability of the electronic equipment.
The contact manner between the electronic device housing and the heat sink can be divided into a direct contact manner and an indirect contact manner. The direct contact type means that the shell of the electronic device is directly attached to the cold plate, and a thinner thermal interface material is coated in the middle. Direct contact thermal conduction can significantly reduce contact resistance after the use of an appropriate thermal interface material, but its use is limited as follows. Firstly, the requirement on the matching degree of the electronic device shell and the heat sink is high, and the flatness and the dimensional matching tolerance must be accurately designed and manufactured. Secondly, for a single board with multiple heat sources, the assembly process of the electronic device is limited, the height of the electronic device needing heat dissipation and a design value usually have certain deviation, and the heat sink in synchronous design cannot be perfectly attached to the multiple electronic devices. And thirdly, the pressing force is proper, the interface contact failure can be caused by the lower pressing force, the contact thermal resistance is increased, and the sensitive device can be damaged by the higher pressing force. Fourthly, the thermal stress and the mechanical stress which are possibly generated in the use process of the assembly directly act on the surface of the electronic device. Fifthly, temperature changes during use of the electronic device may pump the thermal interface material out of the contact surface. Sixthly, the liquid thermal interface material has the performance reduction and even failure caused by aging after long-time use. And seventhly, the heat sink is not suitable for occasions where the electronic device needs to be insulated from the heat sink. In response to the disadvantages and limitations of direct contact heat conduction, non-contact heat conduction technology has been developed and developed rapidly. The most common form of use for non-contact thermal conduction is the use of deformable thermal pads. The heat conducting gasket is a soft solid material with a certain thickness, consists of a silica gel substrate/silicon resin and high heat conducting particles, and can generate unequal compression deformation of 0-50% along the thickness direction under the action of pressure. The heat conducting gasket can solve the problems of assembly tolerance matching, pressing force adjustment, stress decoupling, insulation and long-term use reliability between the multi-electronic equipment and the heat sink, and is widely applied to the electronic industry. However, the thermal conductivity of the thermal conductive gasket widely used in the industry is generally between 1W/(m.K) and 7W/(m.K) due to the poor thermal properties of the substrate, and the highest thermal conductivity of the thermal conductive gasket using the oriented carbon fiber recombination technology in the literature can only reach 30W/(m.K). The low thermal conductivity and the millimeter-scale thickness severely limit the application of the thermal pad in the field of heat dissipation of high heat flux density electronic devices.
The heat pipe/steam cavity heat pipe is a powerful means for solving the problem of heat dissipation of high heat flux density electronic devices, and the heat is efficiently transported along the axial direction or the longitudinal direction by utilizing the circulating phase change of internal working media. The heat pipe/steam cavity heat pipe is composed of copper, aluminum, stainless steel, table alloy and other metals, can not deform normally when being installed in a use process, and is similar to direct contact type heat conduction in a use mode. Part of the flexible heat pipe can be folded along the direction vertical to the thickness direction, and the phase change heat transfer device which can be deformed along the thickness direction is rarely reported. The prior patent CN108780343A discloses a thermal management system including an elastically deformable phase change device, in which an elastic metal is used as a shell of the phase change device, and the metal shell deforms when pressure is applied to adapt to the change of the distance between the cold source and the heat source, and recovers to its original shape after the external force is removed. This patent uses elastic metal's physical characteristic to obtain the deformation effect, exists that the elasticity deformation volume is limited, can't accomplish electric insulation, working medium backward flow capillary is not enough, is difficult to make the regulation to the pressure variation in installation and the use cavity.
Disclosure of Invention
The invention provides a micro-deformation enhanced heat conduction contact phase change heat transfer device which can adapt to the distance change between a cold end and a hot end in the installation and use processes, apply pretightening force, realize electrical insulation between cold and heat sources, strengthen liquid working medium backflow, enhance heat conduction and relieve the pressure impact of upper and lower substrates on electronic components in the installation and use processes.
The invention provides a micro-deformation enhanced heat conduction contact phase change heat transfer device which comprises an upper substrate, a lower substrate, a micro-deformation side wall, a liquid charging pipe, a pressure adjusting mechanism, a wire mesh capillary core and a working medium. The upper and lower substrates, the micro-deformation side wall and the liquid filling pipe are welded to form a cavity, the pressure regulating mechanism is communicated with the cavity, the wire mesh capillary cores are laid on the inner sides of the upper substrate part and the lower substrate part of the cavity, and the cavity is filled with working medium through the liquid filling pipe. When the heat transfer device is used, the lower substrate is attached to the cold end, the upper substrate is attached to the hot end, the micro-deformation side wall can deform under the action of installation pressure, and the micro-deformation enhanced heat conduction contact phase change heat transfer device transfers heat from the hot end to the cold end by means of the cyclic flow phase change of working media in the wire mesh capillary core and the cavity.
Preferably, the micro-deformation side wall is of an annular structure, the diameter of the micro-deformation side wall is 10-20 mm, the height of the micro-deformation side wall is 5-10 mm, the middle of the micro-deformation side wall is provided with a V-shaped or S-shaped deformation structure, the micro-deformation side wall can be elastically deformed under the pressure of 1-100N, and the relative deformation amount is less than or equal to 25%.
Preferably, the material of the micro-deformation side wall is copper, aluminum or an organic polymer material.
Preferably, the pressure regulating structure is a spring piston structure.
Preferably, the wire mesh capillary core structure is a woven wire mesh made of copper, aluminum or an organic polymer material.
Compared with the prior art, the invention has the following advantages:
the elastic structure is arranged on the side wall of the steam cavity heat pipe, so that the steam cavity heat pipe can adapt to the distance change between the cold end and the hot end in the installation and use processes, and simultaneously, pretightening force is simultaneously applied between the cold end and the lower substrate and between the hot end and the upper substrate, so that the contact thermal resistance is reduced, and the upper substrate and the lower substrate can be insulated according to the requirement; the wire mesh capillary cores are laid on the upper substrate and the lower substrate, so that liquid backflow is enhanced, and the heat transfer performance of the phase change device is enhanced; by adding the pressure adjusting structure, the pressure impact of the upper and lower substrates on the electronic components in the installation and use process is relieved.
Drawings
FIG. 1 is a schematic view of the apparatus of the present invention.
FIG. 2 is a schematic diagram of the elastic structure of the sidewall of the device of the present invention.
Fig. 3 is a schematic view of the pressure regulating mechanism of the device of the present invention.
The figure comprises an upper substrate 1, a lower substrate 2, a micro-deformation side wall 3, a liquid charging pipe 4, a pressure adjusting mechanism 5, a screen capillary core 6, a working medium 7, an upper cavity 51, a lower cavity 52, an upper spring 53, a lower spring 54, a piston 55 and a communicating pipe 56.
Detailed Description
The invention is further described below with reference to the accompanying drawings.
Fig. 1 shows a schematic diagram of the device of the present invention, which comprises an upper substrate 1, a lower substrate 2, a micro-deformation sidewall 3, a liquid charging tube 4, a pressure adjusting mechanism 5, a wire mesh capillary wick 6 and a working medium 7. The upper substrate 1, the lower substrate 2, the micro-deformation side wall 3 and the liquid filling pipe 4 are welded and formed to form a cavity, the pressure adjusting mechanism 5 is communicated with the cavity, the wire mesh capillary core 6 is laid on the inner side of the cavity of the upper substrate and the lower substrate and is tightly connected with the cavity, the cavity is vacuumized and filled with a proper amount of working medium 7 through the liquid filling pipe 4, and the liquid filling pipe is sealed after filling is completed. Lower base plate 2 and cold junction laminating when little deformation reinforcing heat conduction contact phase transition heat transfer device installs, upper substrate 1 and hot junction laminating, little deformation lateral wall 3 can take place elastic deformation under the installation pressure effect, little deformation lateral wall 3 resumes original height after the pressure is got rid of. In a working state, the working medium 7 is sucked to the inner wall of the upper substrate 1 by the wire mesh capillary core 6, the phase change is carried out after the heat is absorbed, the working medium is changed into a gas state from a liquid state, the gas state working medium is conveyed to the position close to the inner wall of the lower substrate 2 under the action of pressure difference through the cavity and then condensed into a liquid again, the working medium 7 is sucked to the position close to a heat source by the capillary core 6, and the heat transmission is completed through the phase state change and the mass conveying of the working medium.
In one embodiment, the micro-deformation sidewall 3 and the wire mesh wick 6 are red copper and the working substance 7 is deionized water. In another embodiment, the micro-deformation sidewall 3 and the wire mesh wick 6 are aluminum alloy, and the working medium 7 is acetone. In another embodiment, the micro-deformation sidewall 3 and the wire mesh capillary wick 6 are made of polymer materials, preferably, the micro-deformation sidewall 3 is made of rubber materials, the wire mesh capillary wick 6 is made of chemical fibers, and the working medium 7 is deionized water, so that the upper substrate and the lower substrate are in an insulating state.
FIG. 2 is a schematic diagram of the elastic structure of the sidewall of the device of the present invention. The side wall is of an annular structure, and the middle part can be elastically deformed. The intermediate portion mechanism may be V-shaped or S-shaped as shown in fig. 2(a) and 2(b), respectively. By selecting the base material, designing the wall thickness and the size of the elastic structure, the stress-strain relationship of the micro-deformation enhanced heat conduction contact phase change heat transfer device can be regulated, and the relative deformation amount of the micro-deformation side wall is less than or equal to 25% under the pressure action of 1-100N.
In one embodiment, the inner diameter of the micro-deformation side wall is 15mm, the outer diameter is 17mm, the height is 8mm, the material is red copper, the elastic mechanism is V-shaped, the included angle is 60 degrees, the radial length is 2mm, the thickness is 0.05mm, the height of a single V-shaped unit is 2mm, and 4V-shaped units are provided in total, finite element simulation data show that the structure can be elastically deformed in the longitudinal pressure range of 1-100N, the deformation amount is in direct proportion to the pressure, the absolute deformation amount is 1.85mm under the pressure of 100N, and the relative deformation amount is 23%.
Fig. 3 is a schematic structural diagram of a pressure regulating mechanism of the device of the present invention, which includes an upper chamber 51, a lower chamber 52, an upper spring 53, a lower spring 54, a piston 55 and a communicating tube 56. An upper spring 53 is connected to the upper chamber 51 and a piston 55, a lower spring 54 is connected to the lower chamber 52 and the piston 55, and the piston 55 obstructs the upper and lower chambers and can slide with low resistance between them. The lower chamber 52 is in a vacuum state, and the upper chamber 51 is connected to the vapor chamber of the phase change heat transfer device through a connection pipe 56. The working modes of the pressure regulating mechanism are as follows: when the equipment is not installed, the piston is in a balanced state; when the device is installed, the volume of the steam cavity is instantaneously compressed, the pressure is instantaneously increased, the piston moves downwards, and the pressure change caused by installation is buffered; after the equipment is installed, the working medium with the temperature temporarily raised due to compression transmits heat to the outside, the piston moves upwards, and the balance state is reestablished; when the heat of the heat source is increased, the temperature of a working medium in the equipment is increased, the saturated vapor pressure is increased, and in order to prevent the heat source equipment from being damaged by the suddenly increased vapor pressure, a spring in the pressure adjusting mechanism moves downwards, so that the volume of a vapor cavity is enlarged, and the sudden increase caused by thermal shock is relieved.
Claims (5)
1. A micro-deformation enhanced heat conduction contact phase change heat transfer device is characterized in that: the device comprises an upper substrate, a lower substrate, a micro-deformation side wall, a liquid filling pipe, a pressure adjusting mechanism, a wire mesh capillary core and a working medium; the upper substrate, the lower substrate, the micro-deformation side wall and the liquid filling pipe are welded and formed to form a cavity, the pressure adjusting mechanism is communicated with the cavity, the wire mesh capillary cores are laid on the inner sides of the upper substrate part and the lower substrate part of the cavity, and the cavity is filled with working media through the liquid filling pipe; when the heat transfer device is used, the lower substrate is attached to the cold end, the upper substrate is attached to the hot end, the micro-deformation side wall can deform under the action of installation pressure, and the micro-deformation enhanced heat conduction contact phase change heat transfer device transfers heat from the hot end to the cold end by means of the cyclic flow phase change of working media in the wire mesh capillary core and the cavity.
2. The micro-deformation enhanced thermally conductive contact phase change heat transfer device of claim 1, wherein: the micro-deformation side wall is of an annular structure, the diameter of the micro-deformation side wall is 10-20 mm, the height of the micro-deformation side wall is 5-10 mm, the middle of the micro-deformation side wall is provided with a V-shaped or S-shaped deformation structure, the micro-deformation side wall can be elastically deformed under the pressure action of 1-100N, and the relative deformation amount is less than or equal to 20%.
3. The micro-deformation enhanced thermally conductive contact phase change heat transfer device of claim 1 or claim 2, wherein: the micro-deformation side wall is made of aluminum, copper or an organic polymer material.
4. The micro-deformation enhanced thermally conductive contact phase change heat transfer device of claim 1 or claim 2, wherein: the pressure adjusting structure is a spring piston structure.
5. A micro-deformation enhanced thermal contact phase change heat transfer device according to claim 1 or claim 2, wherein: the wire mesh capillary core is made of aluminum, copper or an organic polymer material.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202122388457.2U CN216011895U (en) | 2021-09-30 | 2021-09-30 | Micro-deformation enhanced heat conduction contact phase change heat transfer device |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202122388457.2U CN216011895U (en) | 2021-09-30 | 2021-09-30 | Micro-deformation enhanced heat conduction contact phase change heat transfer device |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN216011895U true CN216011895U (en) | 2022-03-11 |
Family
ID=80523739
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202122388457.2U Active CN216011895U (en) | 2021-09-30 | 2021-09-30 | Micro-deformation enhanced heat conduction contact phase change heat transfer device |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN216011895U (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113804035A (en) * | 2021-09-30 | 2021-12-17 | 中国船舶重工集团公司第七二四研究所 | Micro-deformation enhanced heat conduction contact phase change heat transfer device |
-
2021
- 2021-09-30 CN CN202122388457.2U patent/CN216011895U/en active Active
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113804035A (en) * | 2021-09-30 | 2021-12-17 | 中国船舶重工集团公司第七二四研究所 | Micro-deformation enhanced heat conduction contact phase change heat transfer device |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US7709951B2 (en) | Thermal pillow | |
| CN100378973C (en) | Housing structure of electronic device and heat radiation method therefor | |
| JP5116278B2 (en) | Method and apparatus for optimizing heat transfer by electronic components | |
| US6651732B2 (en) | Thermally conductive elastomeric heat dissipation assembly with snap-in heat transfer conduit | |
| US7515415B2 (en) | Embedded microchannel cooling package for a central processor unit | |
| CN1274425A (en) | Burn-in board with adaptable heat sink device | |
| CN110494018B (en) | Optical module | |
| CN105611804B (en) | Heat conductive pad, radiator and electronic product | |
| CN206584917U (en) | A kind of gastight ceramic packaging body of upside-down mounting welding core | |
| CN216011895U (en) | Micro-deformation enhanced heat conduction contact phase change heat transfer device | |
| US7096926B2 (en) | Thermal pouch interface | |
| CN106328612A (en) | Chip heat radiation apparatus and electronic assembly thereof | |
| CN111681995B (en) | Thyristor element, thyristor element assembly structure and soft starter | |
| CN107017207B (en) | Semiconductor circuit arragement construction and assembly method with compression gel | |
| CN113804035A (en) | Micro-deformation enhanced heat conduction contact phase change heat transfer device | |
| WO2020011045A1 (en) | Heat dissipation device | |
| CN106158790A (en) | Power module and thermal interface structure thereof | |
| CN113039875B (en) | Heat pipes, cooling modules and terminal equipment | |
| CN114005803A (en) | Integrated embedded micro-channel heat dissipation system and method of micro-system | |
| CN219577673U (en) | Vapor chamber | |
| CN104619156B (en) | Heat abstractor and communication products | |
| JP2006245356A (en) | Electronic device cooling system | |
| CN104392971A (en) | Watchband contact finger type heat conduction device | |
| CN216775160U (en) | A kind of electronic equipment heat dissipation shell assembly | |
| CN116864463A (en) | Cooling device of single-tube power device |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| GR01 | Patent grant | ||
| GR01 | Patent grant |