DESC:TECHNICAL FIELD
[0001] The present subject matter relates to a thermal management device. More particularly and not exclusively, the present invention pertains to a heat sink for heat dissipation from electronic circuits.

BACKGROUND
[0002] In electric/hybrid vehicles, various electrical and electronic parts are involved in running of a drive train or operation of various other electrical components. These include variety of electronic devices such as controllers, power modules etc. Various electronic components are combined in a predetermined design and structure to form an electronic device. These electrical components may include various combinations including resistors, transistors, capacitors, inductors, diodes circuit boards, relays, quartz crystalsand the like. Such electronic components often interact with each other based on inputs received and further transmit signals as per predetermined operation. These components are generally connected to each other based on type of electronic circuit and packed in a closed casing. They tend to get heated up and may fail to function after a certain number of use cycles. Sometimes, the continuous heating up may result into to fire or sparking in the electrical parts.
[0003] Thus, there is a need to effectively dissipate the heat generated by various electrical and electronic components especially in a control unit/controller which plays an important decision-making role when used in a product like automobile or a vehicle. During vehicle running conditions, the control unit/ controller often operate as per a first set of predetermined commands and continuous inputs received from the rider. During other vehicle on conditions, the control unit/ controller operate as per a second set of predetermined commands.

BRIEF DESCRIPTION OF DRAWINGS
[0004] The detailed description is described with reference to the accompanying figures. The same numbers are used throughout the drawings to reference like features and components.
[0005] Figs. 1 illustrates a perspective view of a heat sink in accordance with an embodiment of the present invention.
[0006] Fig. 2 illustrates a front view of a heat sink in accordance with an embodiment of the present invention.
[0007] Fig. 3 illustrates an exploded view of a heat sink in accordance with an embodiment of the present invention.
[0008] Fig. 4 illustrates a perspective view of one or more cylindrical fins of a heat sink in accordance with an embodiment of the present invention.
[0009] Fig. 5 illustrates a method of thermal management in a heat sink in accordance with an embodiment of the present invention.

DETAILED DESCRIPTION OF THE INVENTION
[0010] Conventionally, a heat sink conducts thermal energy away from a heat generating component to the environment by convection, radiation, or further conduction. Heat sinks have an extended surface area to improve heat dissipation to the environment. In other known heat sinks, a flexible heat sink article is provided which comprises plurality of surfaces having protrusions. The heat sink article maybe provided in different type of materials.
[0011] In a known electronic device, the electronic device contains integrated circuits. During operation of electronic device, the electronic components such as integrated circuits produce heat. The heat from components in the electronic device is localized in various hot spots. These hot spots can make portions of the device undesirably warm relative to other portions. Therefore, it is desirable to improve thermal management of the electronic device.
[0012] In a known electronic device, the electronic device is provided a heat dissipating device such as a heat spreader. The heat dissipating device includes a first heat spreader layer, a second heat spreader layer, a first spacer and a first phase change material (PCM). The first spacer is coupled to the first heat spreader layer and the second heat spreader layer. The first phase change material (PCM) is located between the first heat spreader layer, the second heat spreader layer and the first spacer. However, provision of a heat spreader tends to increase the size of the electronic device.
[0013] Hence the objective of the present invention is to provide an improved heat sing which is compactly packed and efficiently cools the electronic device by cooling down the heat generated by the electronic circuit.
[0014] The electronic device of the present invention may function as a control unit which may be required to be operational for a long duration of time. A conventionally electronic device as per known arts may tend to produce hot spots in specific portions of the electronic device which is an additional problem to be resolved as per the present invention.
[0015] In an aspect of the present invention, a heat sink is comprising a heat sink base member attached to an electronic circuitry.. The A plurality of components to, which the heat sink is connected, generate heat during an electronically active state. To cool down the heat generated by the plurality of electronic components, the heat sink includes a base member, a plurality of cylindrical fins disposed on the base member. The heat generating plurality of electronic components are disposed on the base member. On one side of the base member is provided a fan to channelize forced air to the heat base member. Further, the base member is provided a plurality of sets of cylindrical fins on one side wherein dimensions of one or more set of the plurality of sets of cylindrical fins being different from other set of cylindrical fins. Each set of cylindrical fins include plurality of cylindrical fins. As per an aspect second set of cylindrical fins being more in number as compared to first set of cylindrical fins. As per another embodiment, second cylindrical fin set being disposed around the gap and are on a peripheral portion of heat sink base member.
[0016] In another aspect of the present invention, a method of thermal management in an electronic device is disclosed. The method of thermal management of the electronic device includes firstly operating an electronic device. Thereafter, generating heat on one side of the base member due to operation of plurality of electronic components disposed on the electronic circuitry and at the same time, forced air cooling means provided on the other side of the base member. Subsequently, the forced air from the other side and the heat from the first side is transferred to the heat sink from opposite sides of the heat sink base member. Thereafter, receiving heat from first side and forced air side, cooling of heat is achieved through plurality of sets of cylindrical fins disposed on the heat sink base member wherein dimensions of the plurality of sets of cylindrical fins being different from each other.
[0017] The present subject matter is further described with reference to accompanying figures. It should be noted that the description and figures merely illustrate the principles of the present subject matter. Various arrangements may be devised that, although not explicitly described or shown herein, encompass the principles of the present subject matter. Moreover, all statements herein reciting principles, aspects, and examples of the present subject matter, as well as specific examples thereof, are intended to encompass equivalents thereof.
[0018] The foregoing disclosure is not intended to limit the present disclosure to the precise forms or particular fields of use disclosed. As such, it is contemplated that various alternate embodiments and/or modifications to the present disclosure, whether explicitly described or implied herein, are possible in light of the disclosure. Having thus described embodiments of the present disclosure, a person of ordinary skill in the art will recognize that changes may be made in form and detail without departing from the scope of the present disclosure. Thus, the present disclosure is limited only by the claims.
[0019] Additionally, all numerical terms, such as, but not limited to, “first”, “second”, “third”, “primary”, “secondary”, “main” or any other ordinary and/or numerical terms, should also be taken only as identifiers, to assist the reader's understanding of the various elements, embodiments, variations and/or modifications of the present disclosure, and may not create any limitations, particularly as to the order, or preference, of any element, embodiment, variation and/or modification relative to, or over, another element, embodiment, variation and/or modification.
[0020] The embodiments of the present invention will now be described in detail with reference to the accompanying drawings.
[0021] Figure 1 of the present invention illustrates a perspective view of a heat sink (100) in accordance with an embodiment of the present invention. The heat sink (100) comprising one or more base member (102, 103, 104). The one or more base members (102, 103, 104) are disposed on a casing (101). The casing (101) is usually made of a sheet metal or a polymer-based material. The role of the casing (101) is to provide an enclosure to a plurality of electronic components (not shown). The casing (101) ensures a shock proof, electrically insulated and a compact housing is ensured for the plurality of electronic components (not shown). Also, the casing (101) ensures that no dust, water or any foreign particles enter inside the casing (101). As per the illustrated embodiment, a heat sink base member (103) and a plate (104) forming part of a forced cooling mechanism are connected or attached to each other on a second side of the heat sink base member (103). Also, the heat sink base member (103) and the plate (104) are integrally connected to the casing (101). As per the illustrated embodiment, heat sink base member (103) is mounted to the casing (101) and the plate (104) is mounted to the heat sink base member (103).
[0022] The heat sink base member (103) includes plurality of sets of cylindrical fins (106, 107) which are disposed on one side of the heat sink base member (103) for cooling of the heat generated by the plurality of electronic components.
[0023] As per an illustrated embodiment, the plate (104) being rectangular in shape and having a circular central region wherein a circular space is provided and a fan (105) being disposed in the circular space of the central region of the plate (104). The fan (105) is configured as forced air-cooling fan (105) which pulls cooling air from an outer environment towards the heat sink base member (103). As a result, the fan (105) is configured to transmit forced air to the heat sink base member (103).
[0024] Figure 2 of the present invention illustrates a front view of an heat sink (100) in accordance with an embodiment of the present invention. As per the illustrated embodiment, the plate (104) is mounted on heat sink base member (103) through plurality of mountings on corner regions of the plate member (104).
[0025] In an alternate embodiment, any other geometrical shaped plate (104) may be mounted on the heat sink base member (103) which is configured to transfer a forced cooling air to the heat sink base member (103).
[0026] As per the illustrated embodiment, the heat sink base member includes plurality of mounting portions (110) which enables a mechanical connection between the heat sink base member (103) and the casing (101).
[0027] Figure 3 of the present invention illustrates a exploded view of an heat sink (100) in accordance with an embodiment of the present invention. As per the illustrated embodiment, a base plate (102) is provided inside the casing (101). The base plate (102) houses plurality of electronic components such that an electronic circuitry is formed on one side of the base plate (102) and connected using a conductive material or a thermal paste. In an embodiment the base plate (102) is a PCB board layer which forms a base for the electronic circuitry and the base plate (102) act as a primary heat receiving region from the electronic circuitry.
[0028] In an alternate embodiment, the electronic circuitry is formed in vicinity of the base plate (102) such that the base plate is primary receiver of heat from the electronic circuitry.
[0029] The base plate (102) is disposed in the casing (101) such that the plurality of electronic components (not shown) are covered by the casing (101). Further, as per the illustrated embodiment, the heat sink base member (103) is disposed parallel to the base plate (102) and a gap is created between the base plate (102) and the heat sink base member (103) wherein heat is transferred from the base plate (102) to the heat sink base member (103) through convection or any similar means.
[0030] In another embodiment, the heat sink base member (103) and the base plate (102) are mechanically connected to each other such that the heat sink base member (103) is provided additional stability in mounting.
[0031] As per the illustrated embodiment, the plate member (104) is disposed on an opposite side of the heat sink base member (103) from that of the base plate (102) such that the heat sink base member (103) is disposed between the bae plate (102) and the plate member (104).
[0032] The heat sink base member (103) is provided with plurality of sets of the cylindrical fins (106, 107) which provide additional surface area for receiving heat from the bae plate (102). The heat received from the first base plate (102) is transferred to the plurality of sets of the cylindrical fins (106, 107) on the heat sink base member (103). The dimensions of the plurality of sets of the cylindrical fins (106, 107) being variable. The variable dimension includes different length of the cylindrical fins. This is provided to ensure that sets of cylindrical fins (106) with longer lengths provide more surface area for the heat to cool down.
[0033] As per the illustrated embodiment, the plurality of sets of the cylindrical fins (106, 107) are placed in vicinity with each other such that an open circular region (108) is provided in a middle portion of the heat sink base member (103) and the plurality of sets of the cylindrical fins (106, 107) are disposed around an outer circumference of the open circular portion (108). The open circular region (108) is provided parallel to the circular area on the third board base member (103) wherein the fan (105) is disposed. The fan (105) distribute the forced air to heat sink base member (103) especially the regions surrounding the outer circumference of the open circular portion (108).
[0034] As per an embodiment, the plurality of sets of the cylindrical fins (106, 107) are disposed in a predetermined configuration such that set of cylindrical fins (106) with higher lengths are concentrated in regions which require more cooling. The regions requiring more cooling are determined according to the hotspot formation due to heat generated by the electronic circuitry.
[0035] Figure 4 illustrates a perspective view of one or more cylindrical fins in accordance with an embodiment of the present invention. As per an embodiment of the present subject matter, the plurality of sets of the cylindrical fins (106, 107) include a first set of cylindrical fins (106) and a second set of cylindrical fins (107). The first set of cylindrical fins (106) having a first length (X) for each of the cylindrical fin in the first set of cylindrical fins (106) and the second set of cylindrical fins (107) having a second length (Y) for each of the cylindrical fin in the second set of cylindrical fins (107). As per an embodiment, the first length (X) being greater than the second length (Y).
[0036] Figure 5 a method of thermal management in an electronic device in accordance with an embodiment of the present invention. The method of thermal management has been divided in five steps. As per the illustrated method, upon operating the electronic device (100) (Step 1 or S1) heat is generated on the base plate due to operation of the one or more electronic components of the electronic circuitry (Step 2A or S2A). At the same time a parallel process occurs on the plate member (104). The plate member receives forced air through the fan (105) (Step 2B or S2B).
[0037] Subsequently, heat is transferred from the base plate (102) to the heat sink base member (103) (Step 3A or S3A) and simultaneously forced air is transferred from the fan (105) to the heat sink base member (103) (Step 3B or S3B) such that forced air and the heat is received by the heat sink base member (103) simultaneously from opposite sides of the heat sink base member (Step 4 or S4). Further, cooling of heat occurs on the heat sink base member through plurality sets of cylindrical fins (106, 107) which are variable in dimensions.
[0038] The claimed steps as discussed herein are not routine, conventional, or well understood in the art, as the claimed steps enable the following solutions to the existing problems in conventional technologies.
[0039] One of the advantage of the present invention is a simple heat sink assembly for effectively cooling an electronic device or an electronic circuitry. As per another benefit, the heat sink works in parallel from 2 different sides enabling enhanced cooling within a compact space. The heat sink can be installed on a compact electronic circuitry and can be configured with local high and low heat dissipation capability based on the need of heat dissipation. Such spatial degree of freedom in cooling provide wide range of flexibility for a design of an electronic circuitry thereby opening up multiple possible permutation and combination of design of an electronic device or circuitry.
[0040] Improvements and modifications may be incorporated herein without deviating from the scope of the invention.

LIST OF REFERENCE NUMERALS

100: Electronic Device
101: Casing
102: Base plate
103: Heat Sink base member
104: Plate member
105: Fan
106: First Set of Cylindrical Fins
107: Second Set of Cylindrical Fins
108: Open Circular Region
110: Plurality of Mounting Portions
X: First Length
Y: Second Length

,CLAIMS:We Claim

1. An heatsink (100) comprising:
a heat sink base member (103) configured to be attached to an electronic circuitry; and
a plurality of cylindrical fin sets (106, 107) being disposed perpendicular on said heat sink base member (103), wherein dimensions of said plurality of cylindrical fin sets (106, 107) being different from each other.
2. The heatsink (100) as claimed in claim 1, comprising a forced cooling mechanism being attached to a second side of the heat sink base member (103), wherein the second side comprises the plurality of cylindrical fin sets (106, 107), and a first side of the heat sink base member (103) is attached to the electronic circuitry.
3. The heatsink (100) as claimed in claim 2, wherein the forced cooling mechanism comprises at least one of air-cooled mechanism or a liquid cooled mechanism, wherein the air-cooled mechanism comprises a fan disposed on a plate (104) and the fan is configured to push air onto the plurality of cylindrical fin sets (106, 107).
4. The heatsink (100) as claimed in claim 1, wherein said plurality of cylindrical fin sets (106, 107) being disposed in proximity to each other.
5. The heatsink (100) as claimed in claim 1, wherein said plurality of cylindrical fin sets (106, 107) includes a first cylindrical fin set (106) and second cylindrical fin set (107).
6. The heatsink (100) as claimed in claim 5 , wherein each fin of said first cylindrical fin set (106) being configured to a have a first length (X) and each fin of said second cylindrical fin set (107) being configured to have a second length (Y), wherein said first length (X) being greater than said second length (Y).
7. The heatsink (100) as claimed in claim 1, wherein said heat sink base member (103) being configured to have a gap (108) of a pre-defined shape in a central region of said heat sink base member (103).
8. The heatsink (100) as claimed in claim 3, wherein said plate (104) being configured to have a fan (105) disposed in a central region of said plate (104).
9. The heatsink (100) as claimed in claim 5, wherein said second cylindrical fin sets (107) being greater in number compared to number of said first cylindrical fin sets (106).
10. The heatsink (100) as claimed in claim 6, wherein said second cylindrical fin set (107) being disposed around said gap and said first cylindrical fin set (106) being disposed on peripheral portions of said heat sink base member (103).
11. The heatsink (100) as claimed in claim 1, wherein the heat sink base member (103) is connected to the electronic circuitry using a conductive material
12. The heatsink (100) as claimed in claim 1, wherein the heat sink base member (103) comprises of a plurality of holes for mounting the heat sink base member (103) onto the electronic circuitry using a mounting mechanism, wherein the mounting mechanism comprises of a plurality of fastening means.
13. The heatsink (100) as claimed in claim 1, wherein the heat sink base member (103) comprises of a plurality of mounting portions configured to receive a plurality of fasteners
14. The heatsink (100) as claimed in claim 4, wherein a height of each of said plurality of cylindrical fin sets (106, 107) being based on an amount of heat generated by one or more electrical components mounted on the electronic circuitry.
15.
16. A method of thermal management in a heat sink (100), said method comprising:
operating an electronic device (S1);
generation of heat on first board layer (102) due to operation of one or more electronic components disposed on base plate (102) (S2A) subsequently transferring heat from base plate (102) to heat sink base member (103) (S3A); and simultaneously
receiving forced air by a fan (105) disposed on a plate member (104) (S2B) subsequently transferring forced air from said fan (105) to heat sink base member (103);
simultaneously said heat sink base member (103) receiving heat from said base plate (102) and said heat sink base member (103) receiving forced air from said fan (105) being disposed on plate member (104), (S4)
wherein heat dissipation is achieved through plurality of sets of cylindrical fins (106, 107) being disposed on said heat sink base member (103) wherein dimensions of said sets of cylindrical fins (106, 107) being different (S5) from each other.