Claims:I/We Claim:

1. An electronic product (100) comprising:
an electronic assembly (102) comprising a plurality of base members (203, 204, 205, 206, 207) with a plurality of electronic components (105) mounted in a predetermined sequence; and
a heat dissipation assembly (208) positioned in thermal contact with at least one of the plurality of base members (203-207) and at least one of the plurality of electronic components (105) disposed on the plurality of base members (203, 204, 205, 206, 207).
2. The electronic product (100) as claimed in claim 1, wherein the plurality of base members (203, 204, 205, 206, 207) comprises a power board (203), a control board (207), a primary voltage conversion board (204), a secondary voltage conversion board (205), and a current sensor board (206).
3. The electronic product (100) as claimed in claim 2, wherein the primary voltage conversion board (205) is positioned proximal to an edge (203c) of the power board (203) and the secondary voltage conversion board (205) is mounted on the primary voltage conversion board (204).
4. The electronic product (100) as claimed in claim 2, wherein the heat dissipation assembly (208) comprises:
a plurality of cooling rails (202a, 202b) positioned in thermal contact with longitudinal sides of the power board (203) facilitating flow of coolant longitudinally and laterally across the power board (203), and
a plurality of heat transfer bridges (106) connected between the plurality of cooling rails (202a, 202b) and in thermal contact with the primary voltage conversion board (204) and the plurality of electronic components (105) on the power board (203) for dissipating the heat from the at least one of the plurality of electronic components (105).
5. The electronic product (100) as claimed in claim 4, wherein the thermal contact between the longitudinal sides of the power board (203) and the plurality of cooling rails (202a, 202b) being established by mounting a plurality of primary thermal interfaces (305) to a plurality of lands (304) extending from a side surface (202d) of each of the plurality of cooling rails (202a, 202b).
6. The electronic product (100) as claimed in claim 5, wherein the control board (207) is mounted in thermal contact to a bottom surface (202e) of each of the plurality of cooling rails (202a, 202b) at a plurality of primary extensions (303) using a secondary thermal interface (501).
7. The electronic product (100) as claimed in claim 6, wherein the bottom surface (202e) of the each of the plurality of cooling rails (202a, 202b) further comprises a plurality of secondary extensions (302) for mounting other components of the electronic product (100).
8. The electronic product (100) as claimed in claim 7, wherein the plurality of lands (304) is formed lower than the plurality of primary extensions (303) and the plurality of primary extensions (303) are formed lower than the plurality of secondary extensions (302), when the electronic assembly (102) is viewed from bottom direction.
9. The electronic product (100) as claimed in claim 2, wherein the control board (207) partially covers a bottom surface (203b) of the power board (203), when the electronic assembly (102) is viewed from a bottom direction.
10. The electronic product (100) as claimed in claim 4, wherein a rear surface of the primary voltage conversion board (204) is in thermal contact with at least one of the plurality of heat transfer bridges via a tertiary thermal interface (601) for dissipating the heat from the at least one primary voltage conversion board (204).
11. The electronic product (100) as claimed in claim 2, wherein the secondary voltage conversion board (205) is removably mounted on a front surface of the primary voltage conversion board (204) using a plurality of fasteners.
12. The electronic product (100) as claimed in claim 2, further comprises a plurality of end covers (103, 104) to cover a plurality of open ends (101a) of a casing, wherein the current sensor board (206) is removably attached to an inner surface (104a) of at least one end cover (104) for ensuring proximity of the current sensor board (206) with a plurality of electrical terminals (107) extending from the power board (203) towards the at least one end cover (104).
13. The electronic product (100) as claimed in claim 12, wherein one of the end covers (104) accommodates an inlet nozzle (201a) for a coolant flowing in the plurality of heat transfer bridges (106).
14. The electronic product (100) as claimed in claim 12, wherein one of the end covers (103) comprises an outlet nozzle (201b) for a coolant flowing in the plurality of heat transfer bridges (106).
15. The electronic product (100) as claimed in claim 12, wherein the at least one end cover (104) comprises a plurality of mounting ribs (701) and a plurality of reinforcement ribs (702) in the inner surface (104a).
16. The electronic product (100) as claimed in claim 4, wherein the each of the plurality of heat transfer bridges (106) comprises a flat external surface (106a) on both sides for establishing thermal contact with the at least one of the plurality of electronic components (105) positioned on the power board (203) and the primary voltage conversion board (205).
, Description:TECHNICAL FIELD
[0001] The present subject matter relates to an electronic product. More particularly and not exclusively, it pertains to construction of the electronic product for it to be temperature maintained and easily assembled, serviced, and maintained.

BACKGROUND
[0002] In recent years, processor-based systems and computer systems have found widespread application in any engineering domain. The processor-based systems are temperature and vibration sensitive. The processor-based systems are susceptible to vibrations during their lifetime, which may lead to functional failure and fatigue damage to it. To be deployed in rugged environments, such as, in power trains of electric vehicles and hybrid electric vehicles, efficient heat dissipation and thermal management needs to be done in the processor-based systems and it needs to be packaged in a manner that the external shocks and vibrations do not affect its functionality. The construction of the processor-based systems is thus critical to longevity, safety, serviceability, and maintainability of the system as well as the application in which it is employed.

BRIEF DESCRIPTION OF DRAWINGS
[0003] 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.
[0004] Figs. 1A-1B exemplarily illustrate an exploded perspective view and a section view of an electronic product;
[0005] Figs. 2A-2B exemplarily illustrate a top perspective view and a bottom perspective view of the electronic assembly with some of the electronic components on the base members;
[0006] Figs. 3A-3C exemplarily illustrate different views of an assembly of the power board;
[0007] Figs. 4A-4B exemplarily illustrates different views of the cooling rails of the heat dissipation assembly;
[0008] Figs. 5A-5B exemplarily illustrate an exploded view and a bottom perspective view of the electronic assembly showing the control board;
[0009] Fig. 6 exemplarily illustrates an exploded view of the electronic assembly showing the primary voltage conversion board and the secondary voltage conversion board; and
[00010] Figs. 7A-7B exemplarily illustrate different views of the end cover with the current sensor board.

DETAILED DESCRIPTION OF THE INVENTION
[00011] In the following description, numerous specific details are set forth to provide a thorough understanding of the embodiments. One skilled in the relevant art will recognize, however, that the techniques described herein can be practiced without one or more of the specific details, or with other methods, components, materials, etc. In other instances, well-known structures, materials, or operations are not shown or described in detail to avoid obscuring certain aspects.
[00012] It is contemplated that the disclosure in the present invention may be applied to any vehicle without defeating the spirit of the present subject matter. The detailed explanation of the constitution of parts other than the present invention which constitutes an essential part has been omitted at suitable places.
[00013] In electric/ hybrid electric vehicles, the parts of the electric drive train, such as, one or more controllers, one or more inverters, power boards, voltage converter boards, etc., tend to get heated up and may fail to function after a certain number of use cycles causing discomfort to the rider of the vehicle, during normal usage and/or prolonged operation. Sometimes, the continuous heating up may also lead to fire propagation in the electric drive train, leading to a catastrophic failure of the electric drive train and the vehicle. Thus, there is a need to effectively dissipate the generated heat in the parts and efficiently cool the parts for good performance and longevity as well as to arrest propagation of fire, if any, for the safety of a product employing the components, such as, the vehicle.
[00014] Based on the output wattage of the electric or hybrid electric vehicle, the number, size, and technical specifications, of the parts in the vehicle, vary. Each of these parts has multiple electrical and electronic components, such as, capacitors, transistors, resistors, etc., whose specifications and ratings also vary. For a higher wattage of the electric drive train of the vehicle, the electrical and electronic components vary in quantity, in size, in ratings, and other technical specifications. With the increased sizes and numbers, the positioning of the electrical and electronic components in the various parts of the electrical drive train is difficult and needs to be performed optimally. With the increased size, density and wattage of the number of the electrical and electronic components in the part, the part or the electronic product becomes bulkier and difficult to assemble, service, and maintain in the vehicle.
[00015] The electrical and electronics components, such as, the ICs, transistors, capacitors, resistors, etc., are usually mounted and soldered to a PCB board. The mounting of these components on the PCB board should not make it heavy, clumsy, congested and difficult for assembly, troubleshooting, maintenance, and replacement. However, if the functionality to be achieved demands numerous such components, the single PCB board getting bulkier, difficult to assemble with a casing, and their mechanical and functional failure in due course of time is inevitable.
[00016] For example, in a conventional design of a PCB based electronic product, such as, a low power controller, the capacity of the controller is low. However, the weight of the electronic components is also low due to the low power rating of the electronic components. Further, such low power controllers are only used in low powered vehicle. Additionally, the electronic components on the PCB exert pressure on the PCB board and the board itself functions as a load bearing member. However, these PCB based low power controllers cannot meet the demands of high-power applications, such as, an electric or a hybrid electric vehicle. These high-power applications require a high power rated electronic product, such as, a high power rated controller.
[00017] The high power rated controllers are bulkier and have heavier electrical and electronic components assembled on a PCB board. The PCB board bears the weight of the heavier, denser, and larger components mounted on it and may give away after some operation cycles due to the vibrations the electronic product is susceptible to. As the PCB fails, the electronic product may fail subsequently resulting in a catastrophe in the high-power applications. Also, assembly of such PCBs within a casing needs additional tooling and utmost care while doing it, thereby increasing man-hours in assembly, servicing, troubleshooting, and maintenance.
[00018] In order to address this, multiple PCB boards may be employed on to which the transistors, ICS, capacitors, etc., based on the functionality to be performed, are segregated. Such multiple PCB boards may be stacked or mounted on to one another within the electronic product. If the PCBs are fastened to each other with components mounted on them, they may all fail electrically or mechanically after a few operation cycles. Also, the pressure applied to tighten the fasteners is also high leading to cracks or failure of the PCB boards. Further, if there is a need to expand the functionality of the electronic product, for example, add additional functions to the existing electronic product, the internal construction of the electronic product must allow plug-and-play of additional PCBs with additional electronic components to perform the additional function. The internal construction must allow mounting of additional PCB with additional components. Thus, there is a need to mount the PCBs to any structural component with the electronic product rather than to each other. Also, there is a need to access, troubleshoot, service, and assemble individual PCBs without disturbing the other components within the electronic product.
[00019] Also, with the increased rated specifications of the electrical and electronic components, such as, maximum voltage specification, frequency band of operation, etc., in high wattage vehicles, the heat dissipation from the electrical and electronic components also increases. If in case the components are located very proximal to each other, apart from inaccessibility, there are high chances of propagation of the generated heat from one component to another, leading to grave increase in the temperature of the PCB board. The components may fail to function beyond a rated temperature, the electrical connections on the PCB board may fail, and the PCB board may get structurally deformed, etc., at higher temperatures. The components may ignite and cause a fire and the fire may propagate, leading to a catastrophic failure of the electric drive train as well as the vehicle employing it. Thus, the components on each of the PCB boards may require a heat dissipation mechanism of their own to maintain operable temperature of the electronic product. Employing such separate heat dissipation mechanisms for each of the PCB boards and their respective components will make the assembly of electronic product clumsy, denser, and heavy and also difficult to access and service. Overall, there exists a problem of potential safety risk to the vehicle and its user. There is a need for an improved heat dissipation assembly for the multiple PCB boards and the electronic components mounted on them, within the electronic product.
[00020] As per known art, the electronic products or vehicle parts, such, inverters, converters, power board, controller, etc., in the electric drive train are provided with a sacrificial member that melts down and creates a space between the electrical and electronic components to arrest propagation of fire. However, probability of the sacrificial member being non-functional at the time of need makes this mechanism not effective. Despite employing the sacrificial member, there still exists a need for extracting heat from the individual components to reduce the probability of drastic increase in the temperatures of the components and the PCB boards in a failsafe manner.
[00021] In an implementation for cooling of the electronic product, and in turn the components constituting the electronic assembly, a heat exchange member is in thermal contact with the casing of the electronic product and forced convection is employed. The heat dissipated from the electrical and electronic components on the PCB boards has to traverse through air-filled gap between the components and the casing. The heat transfer between the components and the casing may not be efficient since air is a poor conductor of heat. In order to ensure that heat is effectively dissipated from the components, it is essential to ensure that the heat generating components are reliably secured to be in thermal contact with the heat exchange member proximal to the casing. Another existing implementation employs liquid cooling for thermal management in the electronic product or the electronic assembly of the electronic product. The electronic product or the electronic assembly as a whole may be immersed into a liquid coolant. However, the liquid coolant is stagnant and efficiency of cooling of the electronic assembly is substantially less. In case of forced liquid flow for cooling individual electrical and electronic components, the electronic product becomes more complex, undesirably large to package and also adds to the cost. Also there exists a challenge of enabling the coolant to reach all the hot zones while maintaining a compact layout. There is exists a need for an active cooling system that dissipates the heat from each of the electrical and electronic components of the electronic assembly, yet not making the electronic assembly undesirably bulky.
[00022] However, introduction of new structural components within the electronic product merely to mount the PCBs in addition to employing an active cooling system to cool the electronic components will make manufacturing, assembly, accessibility, and serviceability of the PCBs and the electronic components cumbersome and tedious.
[00023] Therefore, there exists a need for an improved design of an electronic product that provides ease and safety during assembly, use, maintenance, and servicing, is durable, can sustain shocks and vibrations, with efficient and effective heat transfer from the electrical and electronic components, while curtailing fire propagation and overcoming all problems disclosed above as well as other problems of known art.
[00024] In an embodiment, an electronic product is disclosed. The electronic product comprises an electronic assembly and a heat dissipation assembly. The electronic assembly comprises a plurality of base members with a plurality of electronic components mounted in a predetermined sequence and the heat dissipation assembly positioned in thermal contact with at least one of the plurality of base members and at least one of the plurality of electronic components on the plurality of base members. In an embodiment, the plurality of base members comprises a power board, a control board, a primary voltage conversion board, a secondary voltage conversion board, and a current sensor board. The primary voltage conversion board is positioned proximal to an edge of the power board and the secondary voltage conversion board is mounted on the primary voltage conversion board.
[00025] The heat dissipation assembly comprises a plurality of cooling rails positioned in thermal contact with longitudinal sides of the power board facilitating flow of coolant longitudinally and laterally across the power board, and a plurality of heat transfer bridges connected between the plurality of cooling rails and in thermal contact with the primary voltage conversion board and the plurality of electronic components on the power board for dissipating the heat from the at least one of the plurality of electronic components. Each of the plurality of heat transfer bridges comprises a flat external surface on both sides for establishing thermal contact with the at least one of the plurality of electronic components positioned on the power board and the primary voltage conversion board.
[00026] In an embodiment, the thermal contact between the longitudinal sides of the power board and the plurality of cooling rails is established by mounting a plurality of primary thermal interfaces to a plurality of lands extending from a side surface of each of the plurality of cooling rails. In another embodiment, the control board is mounted by establishing thermal contact to a bottom surface of each of the plurality of cooling rails at a plurality of primary extensions using a secondary thermal interface and a plurality of fasteners.
[00027] In an embodiment, the bottom surface of the each of the plurality of cooling rails further comprises a plurality of secondary extensions for mounting other components of the electronic product. The plurality of lands is formed lower than the plurality of primary extensions and the plurality of primary extensions are formed lower than the plurality of secondary extensions, when the electronic assembly is viewed from bottom direction. The control board partially covers a bottom surface of the power board, when the electronic assembly is viewed from a bottom direction.
[00028] A rear surface of the primary voltage conversion board is in thermal contact with at least one of the plurality of heat transfer bridges via a tertiary thermal interface for dissipating the heat from the at least one voltage conversion board. The secondary voltage conversion board is removably mounted on a front surface of the primary voltage conversion board using a plurality of fasteners.
[00029] The electronic product further comprises a plurality of end covers to cover a plurality of open ends of a casing, wherein the current sensor board is removably attached to an inner surface of at least one end cover for ensuring proximity of the current sensor board with a plurality of electrical terminals extending from the power board towards the at least one end cover. One of the end covers accommodates an inlet nozzle for a coolant flowing in the plurality of heat transfer bridges. One of the end covers comprises an outlet nozzle for a coolant flowing in the plurality of heat transfer bridges. One of the end covers comprises a plurality of mounting ribs and a plurality of reinforcement ribs in the inner surface.
[00030] 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.
[00031] 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.
[00032] In the foregoing specification, the disclosure has been described with reference to specific embodiments. However, as one skilled in the art will appreciate, various embodiments disclosed herein can be modified or otherwise implemented in various other ways without departing from the spirit and scope of the disclosure. Accordingly, this description is to be considered as illustrative and is for the purpose of teaching those skilled in the art the manner of making and using various embodiments of the disclosure. It is to be understood that the forms of the disclosure herein shown and described are to be taken as representative embodiments. Equivalent elements, materials, processes or steps may be substituted for those representatively illustrated and described herein. Moreover, certain features of the disclosure may be utilized independently of the use of other features, all as would be apparent to one skilled in the art after having the benefit of this description of the disclosure. Expressions such as “including”, “comprising”, “incorporating”, “consisting of”, “have”, “is” used to describe and claim the present disclosure are intended to be construed in a non-exclusive manner, namely allowing for items, components or elements not explicitly described also to be present. Reference to the singular is also to be construed to relate to the plural.
[00033] Further, various embodiments disclosed herein are to be taken in the illustrative and explanatory sense, and should in no way be construed as limiting of the present disclosure. All joinder references (e.g., attached, affixed, coupled, connected, etc.) are only used to aid the reader's understanding of the present disclosure, and may not create limitations, particularly as to the position, orientation, or use of the systems and/or methods disclosed herein. Therefore, joinder references, if any, are to be construed broadly. Moreover, such joinder references do not necessarily infer that two elements are directly connected to each other.
[00034] 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.
[00035] It will also be appreciated that one or more of the elements depicted in the drawings/figures can also be implemented in a more separated or integrated manner, or even removed or rendered as inoperable in certain cases, as is useful in accordance with a particular application. Additionally, any signal hatches in the drawings/figures should be considered only as exemplary, and not limiting, unless otherwise specifically specified.
[00036] The embodiments of the present invention will now be described in detail with reference to the accompanying drawings.
[00037] Figs. 1A-1B exemplarily illustrate an exploded perspective view and a section view of an electronic product 100. The section view shown in Fig. 1B is taken along the line AA’ in Fig. 1A. The electronic product 100 may be a part of the drive train of an electric vehicle or a hybrid electric vehicle. The vehicle may be a two-wheeled vehicle, a three wheeled or a multi-wheeled vehicle, such as, a passenger car, a passenger bus, a load carrying truck, etc. The electronic product 100 may be an inverter, a controller, a power conditioning circuit, a voltage converter, etc., of the drive train of the vehicle. The electronic product 100 comprises one or more electronic assemblies, such as, 102. An electronic assembly 102 is a congregation of a multiple electrical and electronic components, such as, 105 connected to each other to achieve a defined function, such as, stepping down voltages, converting AC voltage to DC voltage, etc. As exemplarily illustrated, the electronic product 100 comprises a casing 101 enclosing the electrical and electronic components and a pair of end covers 103, 104. The casing 101 is a hollow geometry cover with open ends enclosing the electronic assembly 102. End covers 103, 104 of the electronic product 100 close the open ends, such as, 101a of the casing 101. The casing 101 has mounting provisions 101b to mount the end covers, such as, a first end cover 103 and a second end cover 104 at the open ends 101a, using attachment means. The second end cover 104 has provisions 104a for the external electrical terminals 107 of the electronic assembly 100. The first end cover 103 seals the casing 101 on the other side. In an embodiment, an outer surface of the casing 101 may comprise a dovetail pattern that facilitates in easy mounting and removal of the electronic product 100 in a designated space in an application, such as, the vehicle. In an embodiment, an inner surface of the casing 101 may comprise a dovetail pattern that facilitates in easy mounting and removal of the electronic assembly 102 into and out of the casing 101 for accessing the mounted electrical and electronic components, such as, 105.
[00038] Figs. 2A-2B exemplarily illustrate a top perspective view and a bottom perspective view of the electronic assembly 102 with some of the electronic components 105 on the base members 203, 204, 205, 206, 207. The electronic assembly 102 comprises one or more base members 203, 204, 205, 206, 207 for mounting multiple electronic components, such as, 105 Each of the base members 203, 204, 205, 206, 207 may be a printed circuit board (PCB), a bread board, an insulated metal substrate (IMS) board, etc. The base members 203, 204, 205, 206, 207 may be, and not limited to, a multi-layered PCB, a rigid PCB, flexible PCB, single layer PCB, aluminum backed PCB, etc. Each of the base members 203, 204, 205, 206, 207 may be for a different function such as voltage conversion, voltage inversion, etc. The base members are a power board 203, a control board 207, a primary voltage conversion board 204, a secondary voltage conversion board 205, and a current sensor board 206. The electronic components, such as, 105 are, for example, transistors, such as, BJTs, MOSFETs, capacitors, resistors, ICs, etc., are mounted on the base members 203-207. The components of a heat dissipation assembly 208 (shown in Fig. 1) are spread in the lateral direction and the longitudinal direction of the power board 203 to extract heat from the electronic components 105 on the different base members 203, 204, and 207 and the base members themselves 203, 204, and 207.
[00039] The heat dissipation assembly 208 comprises a plurality of heat transfer bridges, such as, 106 and two cooling rails 202a, 202b positioned along the longitudinal direction of the power board 203. The cooling rails 202a, 202b carry coolant along the longitudinal direction of the power board 203. The coolant in the cooling rails 202a, 202b flows through the heat transfer bridges 106 to extract heat from the transistors, the capacitors on the power board 203, and the voltage converter boards 204, the power board 203, and the control board 207 respectively and cool the different elements of the electronic assembly 102. The heat transfer bridges 106 extend between the cooling rails 202a, 202b in the lateral direction of the power board 203.
[00040] The cooling rail 202a comprises an inlet nozzle 201a removably engaging with the end cover 104 and an end cap 201c removably engaging with the other end. Similarly, the cooling rail 202b comprises an outlet nozzle 201b removably engaging with the end cover 103 and an end cap (not shown) with the other end. The inlet nozzle 201a and the outlet nozzle 201b are configured to be in longitudinally opposite sides. In an embodiment, the inlet nozzle 201a and the outlet nozzle 201b are in the same direction. The coolant flows into the cooling rail 202a through the inlet nozzle 201a and flows out of the cooling rail 202b through the outlet nozzle 201b. The temperature of the coolant exiting from the outlet nozzle 201b is substantially higher than the temperature of the coolant entering through the inlet nozzle 201a, due to the amount of heat carried away by the coolant while exiting through the outlet nozzle 201b. In an embodiment, the coolant exiting from the outlet nozzle 201b may be cooled and re-circulated into the inlet nozzle 201a through an external recirculation line. The coolant may be water, ethylene glycol, etc.
[00041] As exemplarily illustrated in Fig. 2A, the cooling rails 202a, 202b are proximal to longitudinal sides extending in X-X’ direction of the power board 203. At one end of the power board 203, the primary voltage conversion board 204 is located and the other end of the power board 203, the current sensor board 206 is located. The power board 203 regulates power supply in a high power rated application, such as power supply to drive an electric vehicle. The power board 203 regulates the 3-phase power being supplied to a motor of the electric vehicle. The electronic components 105 on the power board (shown in Fig. 1B) may comprise multiple rows of transistors and multiple rows of capacitors soldered back-to-back to the power board 203 and are spread in a lateral direction Y-Y’ of the power board 203. The pores 209 on a top surface 203a of the power board is the location where the electronic components, such as 105 are soldered. On the rear surface 203b, the pins of the electronic components 105 are connected using multiple bus bars (not shown) as the power board 203 handles high voltages.
[00042] The power board 203 is rectangular in shape with the current sensor board 206 in contact with an edge of the power board 203 as seen in Fig. 2A. The primary voltage conversion board 204 is not mounted on the power board 203 but mounted on a heat transfer bridge 106 mounted on the cooling rails 202a, 202b as seen in Fig. 2A. The power board 203 extends between the inlet nozzle 201a and the end cap (not shown) and the outlet nozzle 201b and the end cap 201c as seen in Fig. 3A. The heat transfer bridge 106 is positioned slightly inwards away from the outlet nozzle 201b and the end cap 201c as seen in Fig. 2A.
[00043] As exemplarily illustrated in Fig. 2B, the control board 207 is positioned below the power board 203. When the power board 203 is viewed from the top as seen in Fig. 2A, the control board 207 is hidden. The control board 207 is the brain of the electronic product 100 and takes the decision to control the functioning of the electronic product 100 and the high power rated application, such as the vehicle. Multiple components, such as, 105 are mounted to the control board 207. However, the voltages at which the components 105 operate are relatively low (about 5V) and thus, the size of the components 105 is also less. When the electronic assembly 102 is viewed from the bottom direction as in Fig. 2B, the control board 207 partially covers the rear surface 203b of the power board 203. The control board 207 is also mounted to the cooling rails 202a, 202b. The electronic components 105 of the control board 207, being small, generate less heat and thus the amount of heat to be extracted is also low. The control board 207 with copper tracks underneath also requires some cooling as the board surface 207b tends to increase in temperature with continuous operation. The coolant in the cooling rails 202a, 202b aids in maintaining optimal temperatures.
[00044] The control board 207 is also rectangular in shape with cutouts to accommodate mounting provisions, such as, 302 in the cooling rails 202a, 202b to mount other components, such as, packaging members. The control board 207 is mounted to the cooling rails 202a, 202b in a manner that it extends from the end where the primary voltage conversion board 204 is mounted to the heat transfer bridge 106.
[00045] Figs. 3A-3C exemplarily illustrate different views of an assembly of the power board 203. As exemplarily illustrated, the power board 203 is mounted to a side surface 202d of the cooling rails 202a, 202b and in the space between the cooling rails 202a, 202b. The components 105 on the top surface 203a of the power board 203 that generate heat are cooled by the heat transfer bridges 106. The power board 203 itself is cooled by the coolant flowing through the cooling rails 202a, 202b. To mount the power board 203, on the side surface 202d of the cooling rails 202a, 202b, irregular flat extensions, referred to as lands 304, are provided. The lands 304 have mounting provisions 304a to mount the power board 203 over it. The mounting provisions 304a are in-line with the mounting apertures in the power board 203.
[00046] To establish thermal contact between the power board 203 and the lands 304 in the cooling rails 202a, 202b a primary thermal interface 305 is provided between them. The assembly involves the positioning of the thermal interface 305 on the lands 304 and then positioning the power board 203 over it. These three 203, 305, and 304 are fastened using fasteners 301. Though the lands 304 extend from the side surface 202d, these lands 304 face in upwards direction with the mounting provisions 304a on them. The cooling rails 202a, 202b may be rectangular or circular in shape. The bottom surface 202e of the cooling rails 202a, 202b comprises extensions 302, 303 for mounting other components of the electronic product. The lands 304 are formed between such extensions 302, 303 and the power board 203 is fastened on such lands 304 as seen in Fig. 3B. The shape of the thermal interface 305 is in-line with the shape of the lands 304. The flat thermal interface 305 has multiple cut-outs to comply with the shape of the lands 304. After mounting the power board 203 on the lands 304, the components 105 on the top surface 203a of the power board 203 are soldered. Also, can be seen in Fig. 3B, the bottom elevation view of the power board 203 on the cooling rails shows that on the bottom surface 202e of the cooling rails 202a, 202b at the extensions 303, the control board 207 can be mounted without touching the power board 203.
[00047] Figs. 4A-4B exemplarily illustrates different perspective views of the cooling rails 202a, 202b. As exemplarily illustrated in the top view in Fig. 4B, on the top surface 202f of the cooling rails 202a, 202b, mounting provisions 401 are provided to mount the heat transfer bridges 106. The two cooling rails 202a, 202b are parallel to each other with the inlet nozzle 201a and the outlet nozzle 201b in opposite ends. The power board 203 and the control board 207 are also mounted to the cooling rails 202a, 202b. The inlets and the outlets to the heat transfer bridges 106 are mounted into the mounting provisions 401. The inlet of each of the heat transfer bridges 106 is on the cooling rail 202a and the outlet of each of the heat transfer bridges 106 is on the cooling rail 202b. The raised openings 402 are for equalizing the pressure of the coolant in the cooling rails 202a, 202b. In the bottom perspective view as shown in the Fig. 4A, the lands 304 are formed in the side surface 202d of the cooling rails 202a, 202b. Apart from the lands 304, the mounting extensions 303 on the bottom surface 202e of the cooling rails 202a, 202b is for mounting the control board 207. The other mounting extensions 302 as indicated are for mounting other accessories of the electronic product 100. The mounting extensions 303 are lower in height compared to the mounting extensions 302 as can be seen in Figs. 3A-3C. This ensures a gap between the mounting of the control board 207 to the extensions 303 and the mounting of the accessories on the extensions 302. The lands 304 are formed on the side surface 202d at a height lower than the extensions 302 and 303. This ensures there is gap between the power board 203 and the control board 207 on assembly of the electronic assembly 102.
[00048] Figs. 5A-5B exemplarily illustrate an exploded view and a bottom perspective view of the electronic assembly 102 showing the control board 207. The control board 207 is mounted on the extensions 303 provided on the bottom surface 202e of the cooling rails 202a, 202b, proximal to the rear edge 203c of the power board 203. The components 105 on the control board 207 are smaller in size and wattage and thus, do not require any direct cooling. However, the control board 207 itself requires cooling which is achieved by the thermal contact between the control board 207 and the coolant in the cooling rails 202a, 202b. To establish the thermal contact between the control board 207 and the cooling rails 202a, 202b, a secondary thermal interface 501 is positioned between them. The shape of the thermal interface 501 complies with the shape of the bottom surface 202e of the cooling rails 202a, 202b along with the extensions 303. The control board 207, the secondary thermal interface 501, and the cooling rails 202a, 202b are fastened together using fasteners 502 as indicated in Fig. 5A. On the cooling rail 202b, the extensions 303 to mount are closer to the outlet nozzle 201b and on the other cooling rail 202a, the extensions 303 are formed closer to the end cap 202c.
[00049] By mounting the power board 203 on the lands 304 and the control board 207 on the extensions 303, the control board 207 is positioned lower than the power board 203 and no contact is ensured between them. The extensions 303 are formed slightly higher on the bottom surface 202e of the cooling rails 202a, 202b than the position of the lands 304 formed in the side surface 202d of the cooling rails 202a, 202b. In an embodiment, the extensions 303 extends from the side surface 202d of the cooling rails 202a, 202b. The other mounting provisions 302 are visible and remain undisturbed after mounting the control board 207 to the extensions 303.
[00050] Fig. 6 exemplarily illustrates an exploded view of the electronic assembly 102 showing the primary voltage conversion board 204 and the secondary voltage conversion board 205. The primary voltage conversion board 204 steps down a high voltage to a low voltage. The primary voltage conversion board 204 may be aluminum backed PCB with ICs on its rear surface. The front surface of the primary voltage conversion board 204 is in thermal contact with the heat transfer bridge 106. On the rear surface of the primary voltage conversion board 204, a secondary voltage conversion board 205 is also mounted using multiple fasteners.
[00051] The primary voltage conversion board 204 is mounted on the heat transfer bridge 106 via a tertiary thermal interface 601 to establish thermal contact between them. The heat transfer bridge 106 extends between the plurality of cooling rails 202a, 202b and is in thermal contact with the primary voltage conversion board 204 for dissipating the heat from the primary voltage conversion board 204. The heat transfer bridge 106 comprises an inlet port removably connected to the cooling rail 202a for the coolant to flow in, an outlet port removably connected to another cooling rail 202b for the coolant to flow out after extracting heat from the voltage conversion board 204, and a flat external surface 106a. The voltage conversion board 204 is mounted to the flat external surface 106a via the tertiary thermal interface 601 and multiple fasteners 602. The heat transfer bridge 106 and the primary voltage conversion board 204 are not in contact with the power board 203. There is a slight gap between them. The heat transfer bridge 106 with the voltage conversion board 204 is located proximal at the rear edge 203c of the power board 203. Thus, the primary voltage conversion board 204 is visible on the top surface 203a of the power board 203.
[00052] Figs. 7A-7B exemplarily illustrate exploded and assembled views of the end cover 104 with the current sensor board 206. As exemplarily illustrated, the current sensor board 206 comprising sensors is mounted to the end cover 104 at the mounting ribs 701 provided on the rear surface 104a of the end cover 104. The current sensor board 206 has apertures for the electrical terminals 107 extending from the power board 203 to protrude through the end cover 104 and be accessible external to the electronic product 100. In addition to the mounting ribs 701, the end cover 104 also has reinforcement ribs 702 to strengthen the end cover 104 to sustain external vibrations. The holes 104a in the end cover 104 for the electrical terminals 107 are oriented with the apertures in the current sensor board 206. The current sensor board 206 senses the current available at the electrical terminals 107 and indicates to the control board 207, the normal or abnormal functioning of the electronic product 100. To communicate with the control board 207, a communication port 703 is mounted on the current sensor board 206 that connects the current sensor board 206 to the control board 207. The current sensor board 206 apart from sensing current in the terminals 107, provides mechanical support to the terminals 107 and holds the electrical terminals 107 sturdy.
[00053] The electronic product with the electronic assembly and the heat dissipation assembly as disclosed in the present invention provides the following technical advancement in the field of design of electronic products: During normal operation of the electronic products, the temperature of electronic components within rises. During charging, overcharging, and extended operation, the temperatures may drastically rise. In both these conditions, the heat dissipation assembly and its associated components, such as the coolant, the cooling rails, the bridges, extract and dissipate the heat away from the electronic components. The bridges reduce the temperature of the individual electronic components, such as, transistors, capacitors, etc., and subsequently cool the electronic assembly and the electronic product actively and efficiently. The assembly of the bridges along with the power board, the control board, the voltage conversion boards and the current sensor board ensures a compact packaging of the electronic assembly and the electronic product.
[00054] Since the inlet ports and the outlet ports are connected to same set of cooling rails, compact packaging of the heat dissipation assembly and the electronic assembly is feasible. Since the cooling bridges are parallel, the flow through the bridges is balanced. In an embodiment, the flow rates to individual bridges can be varied based on the temperatures of the electronic components being cooled. To maintain continuous flow of the coolant, the pressure in both the cooling rails is equalized using raised openings in the cooling rails. The design of the electronic assembly with the heat dissipation assembly ensures cooling of all the major thermal contributors in the electronic assembly. The assembly of the electronic components on the base members and the assembly of the components of the heat dissipation assembly are not cumbersome and are guided by the features of the components, such as, the inlet port, the outlet port, the end caps, the nozzles, etc. With a common bridge that cools multiple electronic components, the crowding of the components and their respective heat sinks is avoided, thereby reducing weight of the electronic assembly, number of parts to be assembled, cost of the electronic assembly, and their associated costs.
[00055] The fastening of the base members to each other is avoided and the thus the stress of fastening them together is avoided. However, to mount the base members, use of additional structure members are avoided and existing cooling rails of the heat dissipation assembly are configured to perform this function. Thus, there are no additional components installed within the electronic product. The contact between the control board and the power board are avoided by configuring the extensions at different heights on the bottom surface of the cooling rails. So, the incidence of short circuiting, heat propagation between the base members, and the load transfer between the base members is prevented.
[00056] Due to the compact packaging of the electronic assembly and the heat dissipation assembly within the casing, the dimensions of the electronic product are also reduced, making space for other additional features in a space crunched vehicle. The components of the electronic product are all modular and can be added to the existing circuit design of the existing electronic product with ease, to achieve prolonged operation of the electronic product, higher efficiency throughout its operation, and avoiding occurrences of any kind of catastrophes in the space crunched applications. The heat dissipation assembly can also function along with existing cooling mechanism of the electronic product. The sealing of the coolant in the bridges is also taken care by configuring the covers on the bridges and the end caps in the cooling rails, to prevent the leakage of the coolant.
[00057] The components of the heat dissipation assembly are light weight, have features that guide in mounting while assembly, maintenance, and servicing, are thin not occupying more space, making the electronic product compact, as well as safe to use, preventing thermal runaway and elevated operating temperatures. The electronic product with such an electronic assembly has wattage in the range of about 0-50 kW and finds application in space constrained mobile devices, products, vehicle, such, two-wheelers, three-wheelers, or any multi-wheeled vehicle, such passenger trucks that experience lot of shock and vibrations. The components of the electronic assembly are tightly lodged into the base members, the base members are tightly mounted on the cooling rails and do not get dislodged due to vibration and shocks. Also, the packaging of the base members in the electronic product results in maintaining least cable length between the base members.
[00058] Thus, the mounting of the base members forming the electronic assembly as per present invention provide mechanical stability, thermal stability, durability, vibration isolation, and impact resistance to the electronic product while enabling breaking of trade-off on variety creation versus ease of manufacturing and assembly leading to a reliable electronic product for a powered device along with a robust casing capable of withstanding various loads arising out of its usage as well as its process of assembly cum manufacturing.
[00059] Improvements and modifications may be incorporated herein without deviating from the scope of the invention
LIST OF REFERENCE NUMERALS
100- Electronic product
101- Casing
101a- open ends
102- Electronic assembly
103- First end cover
104- Second end cover
104a- provision for electrical terminal
105- electronic components
106-heat transfer bridge
107-electrical terminals
201a-inlet nozzle
201b-outlet nozzle
202a, 202b- cooling rails
202c- end cap
202d-side surface
202e-bottom surface
203- power board
203a- top surface
203b-bottom surface
203c- rear edge
204-control board
205-primary voltage conversion board
206-secondary voltage conversion board
207-current sensor board
208- heat dissipation assembly
203-208- heat transfer bridges
209-pores on top surface
301-fasteners
302, 303-extensions
304-lands
305- primary thermal interface
401- mounting provisions for heat transfer bridges
402-raised openings
501-secondary thermal interface
502-fasteners
601-tertiary thermal interface
602- fasteners
701-mounting ribs
702-reinforcement ribs
703-communication port
704-fasteners