RU2820075C1 - System of conductive heat removal from electronic modules of main-modular form factor for package electronics products - Google Patents

Abstract

FIELD: electronics; electronic equipment.

SUBSTANCE: invention relates to can be used to design a system for removing heat energy from heat-generating components of radio-electronic products—electronic modules. System of conductive heat removal from electronic modules of the main-modular form factor for package electronics products, including housing, wherein two inner opposite upper and lower walls of the housing are provided with ribs forming on the upper and lower walls of the housing a system of grooves located at intervals, corresponding to location interval of functional electronic modules of cPCI-Serial format with conductive heat removal system in housings protected from external factors, installed in the backplane, each module is equipped with a heat-removing plate protruding beyond the dimensions of the module, installed by means of mechanical attachment on printed circuit board of electronic module or on radiator of electronic module, wherein the plate is equipped on its two opposite edges with locks, fixing the plate in the grooves of the two opposite upper and lower walls of the housing by the bracing method, at that, the heat-removing plate simultaneously fixes the electronic module in the product housing, at least two power supply modules with backplanes are installed on the flat side walls of the housing, power supply modules are pressed through heat-removing plate by means of wedge locks to inner side walls of the housing with provision for reduction of thermal load on the upper and lower walls of the housing.

EFFECT: creation of system of conductive heat removal from electronic modules of main-modular system of form factor for package electronics products, meeting modern requirements for manufacturability, maintainability, reliability, resistance to external factors, durability, ease of installation and operation, with the possibility of using modern heat-emitting modules in the required quantity in the composition of the housing product.

8 cl, 6 dwg

Description

APPLICATION AREA

The invention relates to the field of electronics, namely, to electronic technology and can be used to construct a system for removing thermal energy from the heat-generating components of radio-electronic products - electronic modules.

BACKGROUND OF THE ART

Currently, a current trend in electronic engineering is the development of various systems for removing thermal energy from the heat-generating components of radio-electronic products - electronic modules.

Below are known different approaches to creating such systems.

It is known from the art, for example, a solution for a heat removal system implemented in a CompactPCI backbone-modular system with conductive heat removal through wedges to the case - CM Computer Inc. “3U SEF-18HP Military ATR Chassis Performance,” https://www.cmcomputer.com/pdf/CM-3U-ATR-SEFHP-DATASHEET.pdf [1]. This system provides for the removal of heat to the product body by using a system of wedge locks inside the case for each module, made primarily of aluminum, through which the heat flow is transferred from the modules to the walls of the case. Locks are installed along the long edges of the module shell for fixing in the grooves of the guides of the connecting basket or the product body. Heat dissipation from the installed module is provided through the module shell to the housing guides and then to the housing itself. The guides and housing are made of thermally conductive material, usually aluminum or copper.

The disadvantage of developing the system [1] is the impossibility of removing heat from the power source directly to the side walls of the case, bypassing the wedge lock system, as well as the output of interfaces from the module only to the side walls of the case, where the interface connectors should be attached, and output to the front cover is impossible, i.e. To. The space for connecting and laying interface cables on the front cover of the case, located in front of the installed modules, is inaccessible when assembling the case.

Common to the proposed invention and the specified device [1] are the materials used to manufacture the elements, as well as the presence of an element that transports heat from the fuel elements of the electronic module to the upper and lower walls of the product body.

It is known, for example, COOLING DEVICE [2], which relates to the field of electrical engineering and can be used for cooling groups of fuel elements of a printed circuit board, which is designed to ensure effective heat removal from the fuel element and heat dissipation into the surrounding space in the absence of forced cooling, to provide electromagnetic shielding of the fuel element with restrictions on the overall dimensions of the cooling device, the cooling device in contact with the printed circuit board is made of a metal plate. On the surface of the metal plate there are holes for attaching to a printed circuit board, fins, and heat-removing pads in contact with the heat-generating elements, which are connected by cylindrical surfaces to each other and to the fins. In the area of low heating of the cooling device and along the perimeter of the cooling device, there are holes for air inlet, and in the area of high heating of the cooling device, there are holes for air outlet, which are located at the transition points of the heat-removing platforms to the fin area, where the cross-sectional profile of the cooling device changes stepwise (stepwise). ). The size and shape of the holes, their number and the direction of the fins of the cooling device are selected to ensure an optimal temperature difference between the surfaces on which the air inlet holes are located and the surfaces on which the air outlet holes are located. The total area of the air inlet holes is larger than the total area of the air outlet holes. The maximum dimensions and shape of the holes for air inlet and air outlet are limited by the condition of minimal reduction in electromagnetic shielding of the heat-generating elements of the printed circuit board.

There is also a well-known SYSTEM OF CONDUCTIVE HEAT REDUCTION FROM ELECTRONIC MODULES OF STACKED FORM FACTOR FOR PACKAGED ELECTRONICS PRODUCTS [3], which relates to electronic equipment and is intended to ensure the removal of thermal energy from the heat-generating components of elements of packaged radio-electronic products - from electronic modules made in the format of a stacked form - factor a. The technical result is to increase the efficiency of conductive heat removal from electronic modules. The system contains a housing equipped with aluminum parts with ribs installed on its two inner opposite walls, forming a system of grooves, and at least one copper heat-removing plate. A product module with an installed heat sink plate is connected to other modules in a stack. The stack of modules is installed in the product body only by fixing the edges of the heat sink plate on one of the modules with locks in the housing grooves. Heat removal to the housing is carried out due to the tight fit of the edges of the heat sink plate to the side walls of the housing. A tight fit is ensured by fixing the plate in the grooves of the housing with locks that are installed on the edges of each heat sink plate. Heat removal from the module to the plate occurs due to the contact of the plate to the heat-generating elements of the module or to the intermediate cooling radiator. Heat is taken away by the plate and redistributed over its entire area from the module to the side walls of the housing over the entire contact area of the two edges of the plate and the housing in the groove.

The technical result to which the proposed invention is aimed is the creation of a conductive heat removal system from electronic modules of a backbone-modular form factor system for packaged electronics products that meets modern requirements for manufacturability, maintainability, reliability, resistance to external factors, durability, ease of installation and operation, with the possibility of using modern fuel modules in the required quantity as part of the body product.

DISCLOSURE OF INVENTION

The technical result is achieved by the proposed:

1. A system for conductive heat removal from electronic modules of a backbone-modular form factor for packaged electronics products, including a housing, at least one heat sink located inside the housing, which is in close contact with the heat-generating elements of the electronic module, and two internal oppositely located upper and lower walls the housings are equipped with ribs that form a system of grooves on the upper and lower walls of the housing, located at intervals corresponding to the spacing of the product modules installed in the backplane, and the heat sink is made in the form of a heat sink plate that follows the contour of the electronic module, including copper, aluminum or other possible, installed using mechanical fastening on the printed circuit board of the electronic module, and the plate is equipped on its two opposite edges with locks that fix the plate in the grooves of two opposite walls of the housing using the expansion method, while the heat sink plate simultaneously fixes the module in the product body by connecting the plate with printed circuit board, while the overall dimensions of the module with conductive heat removal are regulated, among other things, by the cPCI-S.0 standard in terms of the conductive design of the module, moreover, each module is installed separately in the housing, the modules are installed with the mandatory presence of a heat sink plate, in this case, at least two power supplies are installed, having a similar design to the electronic module, as well as fastening in the form of locks, and the power supplies are installed only in the two extreme positions of the housing with locks pressed against the side walls of the housing, thereby fixing the power source and ensuring heat transfer to side walls of the housing, heat removal to the side walls from power sources is provided to reduce the thermal load on the upper and lower walls of the housing, to ensure increased efficiency of heat removal from electronic modules that remove heat to the upper and lower walls of the housing.

2. The conductive heat removal system according to claim 1, which provides for heat removal by the power source to the upper and lower walls of the housing.

3. The conductive heat removal system according to claim 1, in which the heat removal plate is made of aluminum.

4. The conductive heat removal system according to claim 1, in which the heat removal plate has a protective galvanic coating.

5. The conductive heat removal system according to claim 1, in which the heat removal plate has a protective powder coating.

6. The conductive heat dissipation system according to claim 1, in which the heat sink plate has cutouts for tall components and module connectors.

7. The conductive heat removal system according to claim 1, in which the heat sink plate has holes for laying cables and other connectors.

8. The conductive heat removal system according to claim 1, in which a copper heat distribution element is installed as an intermediate element between the electronic module and the heat sink plate.

9. The conductive heat removal system according to claim 1, in which the spacing of the grooves on the walls of the housing is regular along the entire length of the side walls of the housing.

10. The conductive heat removal system according to claim 1, in which the groove system is formed by milling ribs on the inner walls of the housing.

11. The conductive heat removal system according to claim 1, in which heat-conducting paste is provided at the contact points between the heat-sinking plate and the housing.

12. The conductive heat removal system according to claim 1, in which heat-conducting paste is provided at the points of contact between the heat-sinking plate and the module cooling radiator.

13. The conductive heat removal system according to claim 1, in which heat-conducting paste is provided at the points of contact between the heat-sinking plate and module components.

14. The conductive heat removal system according to claim 1, in which a heat-conducting volumetric gasket is provided at the points of contact between the heat-sinking plate and module components.

The proposed invention is illustrated in figures 1-6:

In fig. Figure 1 shows a general view of the proposed system, including a conductive processing unit with measured parameters listed in Table 1.

In fig. Figure 2 shows a cross-section of the conductive module 20 from the conductive processing unit of the proposed system, where:

1-19 (see Fig. 1) indicate temperature control points;

20 - conductive module (see Fig. 1);

21 - printed circuit board of the electronic stack module;

22 - heat sink plate;

23 - locks;

24 - fuel-generating components of the module.

In fig. For clarity, Figure 3 shows the conductive processor unit of the proposed system, front view.

In fig. For clarity, Fig. 4 shows the conductive processor unit of the proposed system, side view.

In fig. For clarity, Figure 5 shows the conductive processor unit of the proposed system, rear view.

In fig. For clarity, Fig. 6 shows a cross-section of the conductive processing unit of the proposed system.

The conductive heat removal system works as follows. In fig. Figure 1 shows a general view of the proposed system, including a conductive processing unit with measured parameters listed in Table 1. Numbers 1-19 (see Fig. 1) indicate temperature control points, the ends of the lines indicate the locations of temperature sensors on the outside of the housing. In fig. Figure 2 shows a cross-section of the conductive module 20 from the conductive processing unit of the proposed system. The heat sink plate 22 (see Fig. 2) is installed via a screw connection on the printed circuit board of the electronic stack module 21, and the height is calculated in such a way as to ensure a tight fit of the inner surface of the plate 22 to the heat-generating components 24 of the module. In the case of a processor module, as well as in the case when, in order to obtain higher performance of the heat sink system, a heat distribution plate made, for example, of copper or other highly thermally conductive material is used as an intermediate element between the heat sink plate and the electronic module.

Plate 22 protrudes beyond the dimensions of the module on both sides and locks 23 are installed on these protrusions. Plate 22 is intended for transporting heat, as well as for fixing the module in the housing. The plate 22 is primarily made of aluminum or copper or other similar material, and may also have a protective galvanic or powder coating, but may be made of copper if it is desired to dissipate as much heat as possible. In a particular case, holes in the plate 22 may be provided in the form of additional cutouts for expansion connectors installed on the module, to which other modules can be connected, or in the case of other high components on the module that abut against the plate. The heat sink plate 22 itself has holes for attaching locks 23 and holes for attaching to the element block.

On the inside of the housing (Fig. 1) there is a system of grooves located at equal intervals, the width of which corresponds to the thickness of the plate 22 and the width of the lock 23 (Fig. 2), installed on the plate 22 in a wedged position, and the spacing of the grooves corresponds to the spacing of the modules. - the distance between the backplane connectors.

A system of ribs is formed by milling them on the inner walls of the housing (Fig. 1) since only in this way the thermal resistance is reduced when heat is transferred from the fin to the volume of the housing.

The efficiency of the heat removal system is clearly evident from the results (Table 1) of the following experiments (Fig. 1).

A study was carried out on the efficiency of heat removal, which was assessed by measuring the temperature on simulators of fuel modules and various points of the body, while the temperature of the simulators should not exceed 100°C at an external temperature of a static air environment of +55°C.

Numbers 1-19 (see Fig. 1) indicate temperature control points, the ends of the lines indicate the locations of temperature sensors on the outside of the housing. Two heating elements (resistors) are symmetrically placed on board simulators; the temperature is controlled in the geometric center of the board using a thermocouple. The thermal load on each simulator board was calculated assuming the actual power output of the device installed in this slot. Simulator boards 2-4 are made of copper, boards 1 and 5-11 are made of D16.

Based on measurements 1-5 (Fig. 1), we can conclude that the maximum power dissipation of the case is no more than 240 W in a static environment, the maximum operating temperature is +55°C and overheating is 35°C. The conclusions take into account the presence of air mixing in the heat chamber.

Based on measurements 6, the coating (An. Oke. Black) is more preferable than the coating (Chem. Oke. E) in terms of heat dissipation on the aluminum parts of the block body.

The achieved technical result is to ensure effective heat removal from a group of modules located inside the housing of a radio-electronic product, while simultaneously ensuring high manufacturability of the product with a minimal increase in its cost.

When solving the problem of uniform removal of heat flow to all elements of the case, differentiated heat removal is carried out from the computing modules to the upper and lower sides of the block, and from the power supply modules to the side surfaces of the block, and heat transfer from the power supply modules is not carried out due to wedge locks, but due to direct contact of the heat distribution plate of the power source with the side surface of the housing. Manufacturability is expressed, in particular, in the possibility of displaying interfaces on the front wall of the product body, and on the top or bottom covers without the need to manufacture a separate heat-sinking structure for each electronic module of the product, and also without the need to use additional fasteners for each electronic module in the product body, which significantly saves space inside the product body.

Achieving this result is achieved through the use of at least one heat sink plate with edges protruding beyond the dimensions of the electronic module on both sides as part of the described conductive heat removal system. Each electronic module from which a heat sink is required has its own plate attached, which ensures heat transfer from the heat-generating components of the module to the walls of the housing. The plate is attached with screws to a heatsink mounted on a module - for example, in the case of a processor module or power supply, or is attached to stands on a printed circuit board, with its inner surface adjacent directly to the heat-generating elements of the module. The plate is made of heat-conducting material, mainly copper or aluminum.

Locks are installed on two opposite edges of the heat-sinking plate, allowing the plate to be secured in the grooves of the product body. The lock is, for example, a structure of several sections - wedges, each of which is made of heat-conducting material, preferably aluminum or brass. A fixing screw runs through the center of all sections of the lock. When the locking screw is tightened, the wedges move apart in different directions, which leads to the lock becoming wedged.

To improve the operation of the heat removal system, the following was used in its composition:

- a cooling radiator as an intermediate element between the heat sink plate and the electronic module. In this case, the height of the radiator is calculated so that when installing a heat-sinking plate, the module can be installed in a system of grooves in the housing, made, as a rule, at regular intervals. The heat sink plate may also have a protective galvanic or powder coating. - located in the body of the product, on its two internal opposite walls, aluminum parts with ribs forming a system of grooves at intervals, i.e. the distance separating one groove from another. Heat sink plates with electronic modules installed on them are secured with locks in these grooves. The system of grooves inside the housing can also be made directly on the walls of the housing using the milling method. In this case, the width of each groove corresponds to the sum of the thickness of the heat-sinking plate, the height of the lock installed on the edge of the plate and the gap required to fix the structure with the lock when it is wedged. The slot spacing must correspond to the module stack spacing - the distance between the top edges of the printed circuit boards of modules connected to each other via a backplane (backplane). The spacing of the grooves is usually regular, i.e. made along the entire length of the inner wall of the housing. Parts with ribs in their dimensions correspond to the dimensions, such as width, height of the internal walls of the housing on which these parts are installed.

The regular spacing of the slots inside the housing allows individual modules and/or a stack of modules to be installed in any position inside the housing, which ensures the mobility of elements of the electronics package architecture.

The power supply modules are pressed using wedge locks to the side walls of the case and have their own backplanes, so they do not require regular spacing of the slots.

The body is a cubic-shaped structure, which can be either monolithic, for example, a milled or injection molded part, or made of four walls twisted together and closed at the top and bottom with two lids. The housing is preferably made of aluminum, magnesium alloy or copper.

Heat removal is carried out to the upper and lower walls, on which grooves are made. The side walls of the case, which do not have grooves, are designed to accommodate power supplies. In addition, the front wall of the housing may, among other things, be designed to accommodate interface connectors. The rear wall, among other things, may have a ribbed structure and is intended as an additional heat sink.

The outer surface of the housing walls to which the modules are attached preferably has fins to improve heat dissipation.

The advantage of the proposed case is that the interface connectors located on the front panel and the front strips of the installed modules are located on one side of the case. A special cable management system, located between the hinged front wall of the housing and the installed modules, allows you to quickly replace failed modules without dismantling the external cable connections of the unit or the unit itself from the installation site, which significantly reduces the time spent on restoring the unit’s functionality.

Example

The developed design solution for modular secure computers cPCI-S allows you to simulate computer systems based on cPCI Serial format modules in housings protected from external influences. This solution allows you to install, for example, up to 8 functional modules of the cPCI Serial format with a spacing width of, for example, 5 HP, with a conductive heat dissipation system and using, for example, two power supplies operating in load sharing mode.

For example, the design of a computer includes a case consisting of top and bottom covers, side walls, front and back covers. Inside the case there is a backplane for 8 functional modules, two rear boards for connecting power supplies, and a cabling system.

On the upper and lower parts of the case, on one of the sides (internal from the point of view of the assembled case), a comb is made for installing functional modules; On the other side (external) radiator fins are made to increase heat dissipation efficiency.

On the side parts of the case, on one side (outer from the point of view of the assembled case), radiator fins are provided; the other side of the part is flat, which allows for efficient heat dissipation from the power supply module.

The front cover has connectors for connecting external communication lines. The modules in the structure are installed from the rear cover, which avoids attaching connecting cables to a movable structural element. In the area of the front connectors of functional modules, a cable fixation system is provided, which ensures reliable fixation of connectors without special latches and resistance of the product to shock and vibration.

The arrangement of modules inside the computer is carried out as follows: power supplies using wedge-shaped clamps are pressed with the entire side plane of the power supply against the side walls of the case, functional modules using wedge-shaped clamps at the top and bottom of the module are fixed in the comb of the upper and lower parts of the case.

The connectors on the front panel are connected to the connectors on the front panels of the modules with cables, which are secured using a universal wiring and fixation system.

All of the above examples of the proposed system illustrate, but do not limit all possible uses of the proposed invention.

In the proposed system:

- effective heat removal from the functional modules of the protected computer to the upper and lower walls of the case is ensured;

- effective heat dissipation to the side walls from the power supplies is ensured;

- additional fixation of cables connected to the front connectors of the modules is provided, which makes it possible to ensure maintainability of the computer at the operating site at the module level;

- a universal cable routing system is provided inside the housing.

Thus, the use of the claimed technical solution in the product ensures effective heat removal from the fuel elements located inside the housing, while simultaneously ensuring high manufacturability of the product due to significant savings in internal space with a minimal increase in the cost of the product associated with the additional installation of easy-to-manufacture elements (plates, parts on the walls of the housing with a system of grooves).

The technical result was achieved by creating a conductive heat removal system from electronic modules of a backbone-modular form factor system for packaged electronics products that meets modern requirements for manufacturability, maintainability, reliability, resistance to external factors, durability, ease of installation and operation, with the possibility of using modern fuel modules in the required quantity as part of the enclosure product.

INDUSTRIAL APPLICABILITY

The proposed invention can be used to construct a system for removing thermal energy from heat-generating components of radio-electronic products - electronic modules.

The use of the claimed system ensures effective heat removal from the fuel elements located inside the housing, while simultaneously ensuring high manufacturability of the product due to significant savings in internal space with a minimal increase in the cost of the product associated with the additional installation of easy-to-manufacture elements (plates, parts on the walls of the housing with a system of grooves ).

The proposed system provides effective heat dissipation from the functional modules of the protected computer to the upper and lower walls of the case, provides effective heat dissipation to the side walls from the power supplies, and provides additional fixation of cables connected to the front connectors of the modules, making it possible to ensure maintainability of the computer at the operating site at the level module, and also provides a universal cable routing system inside the housing.

The system of conductive heat removal from electronic modules of the main-module form factor for packaged electronics products is industrially applicable; all modules and structural elements can be produced at any specialized enterprise. The system will find wide application in the field of electronics for removing heat from fuel-generating components of radio-electronic products.

INFORMATION SOURCES:

1. https://www.cmcomputer.com/pdf/CM-3U-ATR-SEFHP-DATASHEET.pdf

2. Patent RU No. 2361378.

3. RU patent No. 2713486.

Claims (8)

1. A system for conductive heat removal from electronic modules of a backbone-modular form factor for packaged electronics products, including a housing, wherein two internal oppositely located upper and lower walls of the housing are equipped with ribs forming a system of grooves on the upper and lower walls of the housing, located at intervals corresponding to interval of arrangement of functional electronic modules of the cPCI-Serial format with a conductive heat sink system in housings protected from external influences, installed in a backplane, each module is equipped with a heat sink plate protruding beyond the dimensions of the module, installed using mechanical fastening on the printed circuit board of the electronic module or on a heatsink for an electronic module, wherein the plate is equipped on its two opposite edges with locks that fix the plate in the grooves of two opposite upper and lower walls of the case using the expansion method, while the heat sink plate simultaneously fixes the electronic module in the product case; at least two modules are installed on the flat side walls of the case power supplies with backplanes, power supply modules through a heat-sinking plate using wedge locks are pressed to the inner side walls of the case, thereby reducing the thermal load on the upper and lower walls of the case. 2. The conductive heat removal system according to claim 1, in which the heat removal plate is made of copper. 3. The conductive heat removal system according to claim 1, in which the heat removal plate is made of aluminum. 4. The conductive heat removal system according to claim 1, in which the heat removal plate has a protective galvanic coating. 5. The conductive heat removal system according to claim 1, in which the heat removal plate has a protective powder coating. 6. The conductive heat dissipation system according to claim 1, in which the heat sink plate has cutouts for tall components and module connectors. 7. The conductive heat removal system according to claim 1, in which a copper heat distribution element is installed as an intermediate element between the electronic module and the heat sink plate. 8. The conductive heat removal system according to claim 1, in which the groove system is formed by milling ribs on the inner walls of the housing.