RU2365070C1 - Radio-electronic block and method of its manufacturing - Google Patents

Abstract

FIELD: physics; radio.

SUBSTANCE: of invention concerns field of radio electronics and can be used at manufacturing of radio-electronic blocks of package type. It is reached because the radio-electronic block contains the case consisting of metal frameworks, elastic sealing interleafs and two walls joined in a package, and also printing assemblies with the demountable connectors, anchored on the mentioned frameworks. The covering and covered stage claws are contained accordingly at end faces of frameworks on their exterior and interior contours, and the height of covering stage claws is less than height of the covered ones, and elastic sealing interleafs are located between end faces of frameworks and the covering stage claws and executed from hermetic. The method of manufacturing of the radio-electronic block includes manufacturing of printing assemblies, their fastening on metal frameworks, arrangement of elastic sealing interleafs at the end faces of frameworks, the makingup of frameworks with two walls in a package and tightening of the package by screws, thus elastic sealing interleafs are disposed after tightening of a package by filling of backlashes with hermetic between end faces of frameworks and covering stage claws.

EFFECT: increase of radio-electronic block reliability.

4 cl, 2 dwg

Description

The invention relates to the field of radio electronics, namely to packet-type radio electronic blocks, in which the metal frames of the electronic modules are part of the housing of the electronic block, and can be used in the manufacture of electronic equipment implemented on the basis of similar electronic modules, for example, communication systems, computer systems, and etc.

A packet-type radio electronic unit is known from the state of the art, consisting of printed units (printed circuit boards) with all attached elements electrically and mechanically connected to them and all performed processing operations: soldering, washing, marking, coating, etc. (P.P. Gell, N.K. Ivanov-Esipovich. Design and microminiaturization of electronic equipment. - L .: Energoatomizdat, 1984, p.115) with one-sided placement of radio-electronic elements (ERE) on the front surfaces, with printed units on the back sides fixed on metal plates and frames connected around the perimeter by screws (RF patent No. 2135298 C1, H05K 7/02, publ. 06/27/1999).

A method of manufacturing such a radio-electronic unit includes the manufacture of printing units with one-sided ERE placement, rigidly connecting the printing units with the back side with metal plates using glue, installing the printing units with metal plates on the frames, assembling the frames into the bag and tightening the bag with screws (RF patent No. 2135298 C1, H05K 7/02, published on June 27, 1999).

The disadvantage of such a radio electronic unit and the method of its manufacture is low reliability due to leakage of the unit.

The disadvantages of such a radio electronic unit are also its large mass and dimensions due to the use of printed units with a one-sided arrangement of ERE, as well as metal plates connected to the rear sides of the printed units.

The closest in technical essence to the claimed radio electronic unit is a radio electronic unit containing a housing consisting of metal frames of G- and T-shaped profiles, at the ends of which grooves and protrusions are located along the perimeter, while elastic gaskets are placed in the grooves, as well as two walls connected to the frames in the package by screws or studs.

The radio-electronic unit also contains printing units with one-way connectors with a single-sided arrangement of ERE, fixed with the backs on the metal plates and the mentioned frames (RF patent No. 2231236 C1, H05K 1/00, H05K 7/20, publ. 06/20/2004).

Closest to the claimed method of manufacturing a radio-electronic unit is a method comprising the manufacture of printing units with a one-sided arrangement of ERE, the rigid connection of the printing units with the back sides with metal plates by means of glue, the manufacture of metal frames of the G- and T-shaped profiles with grooves and protrusions at the ends, placement at the ends of the frames in the grooves of the elastic sealing gaskets, fixing the printing units with metal plates in the framework of the L-and T-shaped profile, the assembly of frames and two x walls in the package and tightening the package with screws or studs (RF patent No. 2231236 C1, H05K 1/00, H05K 7/20, publ. 06/20/2004).

A disadvantage of the known radio-electronic unit and the method of its manufacture is low reliability, since when screws tighten the frames and walls into a bag through elastic gaskets, the frames and walls are deformed (bending), which leads to a violation of the tightness of the housing and a decrease in the efficiency of electromagnetic field shielding. The lack of reliability of the known radio-electronic unit is also determined by the use of printed circuit boards with a one-sided arrangement of ERE, which leads to an increase in the size of printed circuit boards and a decrease in the resistance of the unit to external mechanical influences - vibration, shock, linear acceleration (OST 107.460000.002-89. Electronic modules of the first and the second level of electronic equipment. Design Methods, p. 44, 45).

An increase in the size of printed circuit boards as a result of a one-sided arrangement of ERE also leads to an increase in the dimensions and mass of the block.

The objective of the proposed technical solutions is to increase the reliability of the electronic unit.

The problem is achieved in that in a radio electronic unit containing a housing consisting of metal frames, elastic gaskets and two walls connected to the package by screws or studs, as well as printed units with detachable connectors, mounted on the said frames, at the ends of the frames their external and internal contours contain respectively covering and covered step ledges, while the height of the covering step ledges is less than the height of the covered, and elastic seals nye gasket disposed between the ends of the framework and covering the stepped protrusions and made of a sealant, for example silicone.

This embodiment of the electronic block provides an increase in its reliability by increasing the efficiency of the shielding of the electromagnetic field as a result of tight coupling of the connecting surfaces of the frames and walls forming the block body and reducing the magnitude of the transient electrical resistance between them.

The task is also achieved by the fact that the covering stepped protrusions and (or) the ends of the frames are made with a slope, which ensures a defect-free filling of the gaps with a sealant, it is possible to visually control the quality of the gaskets from the sealant and, if necessary, repair or replace them without disassembling the unit.

The task is also achieved by the fact that the elastic gaskets are made of electrically conductive sealant, for example elastosil 131-55 (TU 6-02-1-472-86), which further improves the efficiency of shielding and reduces the magnitude of the transient electrical resistance between the frames and the walls forming block body.

In addition, the task is achieved by the fact that according to the proposed method of manufacturing a radio electronic unit, including the manufacture of printing units, fixing them on a metal frame, placing elastic sealing gaskets on the ends of the metal frames, assembling the metal frames and two walls into a bag and tightening the bag with screws or studs , elastic sealing gaskets are placed after tightening the bag by filling with sealant the gaps between the ends of the frames and the surrounding stepped protrusion s, for example, by means of a metering device. This allows for the manufacture of a sealed radio electronic unit with effective shielding of the electromagnetic field as a result of tight coupling of the connecting surfaces of the frames and walls forming the housing of the electronic block, as well as sealing the joints with a sealant.

The essence of the proposal is illustrated by drawings.

Figure 1 shows a General view of the electronic block in section. The block comprises a housing 1, formed by metal frames 2, elastic gaskets 3 and walls 4, fastened with screws 5 in the package. On the basis of 2, printing units 6 with detachable connectors 7 are fixed, as well as external electrical connectors 8, electrically connected with detachable connectors 7 and printing unit 6 ribbon wires 9 (OST 4G 0.054.316-84. Installation of ribbon wires in connectors and on printed circuit boards).

Figure 1 a, b, c, d shows fragments of various embodiments of the covering step ledge 10 and the end of the frame 12 (with the shape of the covered step ledge 11 being unchanged), which not only ensure tight coupling of the connecting surfaces, but also simplify the filling of the gaps with sealant. On figa covering the step of the protrusion 10 and the end of the frame 12 is made without bias; on figb - the end face of the frame 12 is made with a slope; on figv covering step ledge 10 is made with a slope; Fig.1d with a slope made and covering the step ledge 10, and the end of the frame 12. The presence of slopes on the covering step ledges and (or) the ends of the frames contributes to the defect-free filling of gaps with sealant, provides the ability to visually control the quality of the gaskets from the sealant and, if necessary, their repair or replacement without disassembling the unit.

Figure 2 shows the electronic module, which is a typical structural element of the proposed electronic unit, containing a metal frame 2 with 10 covering and 11 covered with step ledges and an end 12, on which through the threaded sleeves 13 is mounted a printing unit 6, consisting of a printed circuit board 14 with detachable connectors 7 and ERE 15 located on both sides of the board 14; in the upper part of the frame 2, external electrical connectors 8 are fixed, electrically connected to detachable connectors 7 and the printing unit 6 by means of tape wires 9.

Thus, the technical result of the proposal is to increase the reliability of the radio-electronic unit as a result of improving the efficiency of the electromagnetic field shielding and the tightness of the housing, as well as reducing the transient electrical resistance between the frames and the walls that make up the housing of the unit due to the tight coupling of the connecting surfaces of the frames and walls and sealing the joints .

In addition, in the proposed radio-electronic unit, in contrast to the well-known radio-electronic units of the packet type, the use of printed units with one-sided placement of ERE is not required. Therefore, as a result of the use of printing units with double-sided placement of ERE in the proposed device, a reduction in the dimensions and mass of the electronic unit is achieved, as well as an additional increase in its reliability due to an increase in the stability of the printed units to external mechanical stresses while reducing the size of their printed circuit boards (OST 107. 460000.002-89 Electronic Modules of the First and Second Levels of Radio-Electronic Means. Design Methods. S.44, 45).

An example of a specific implementation of the method.

On glass-epoxy printed circuit boards by 14 well-known methods (Mengin C.-G., Maclelland S. Surface mounting technology. The future of assembly technology in electronics. Translated from English, Moscow: Mir, 1990) ERE 15 and plug connectors 7 are installed and mounted DOD-C-55302 OPL D Connectors from Hypertronics Corporation and perform all necessary operations (soldering, washing, forming a moisture-proof coating, marking), resulting in printing units 6. Then, external electrical connectors of type 8 H6 signify Aring 600 are fixed on the metal frames 2 series as well as, among using threaded sleeves 13, the printing units 6, after which the ribbon wires 9 perform (in accordance with OST 4G 0.054.316-84) the electrical connections of the shanks of the contacts of the connectors 7 and 8, resulting in an electronic module (figure 2).

Then the modules are assembled in a package with two walls 4, the screws 5 are installed technologically (without tightening), and as a result of the jointing of the connectors 7, the necessary electrical connections between the electronic modules are obtained. Then, the obtained electronic unit through the connectors 8 is connected to an external electrical circuit, control its functioning, adjust (if necessary) and technological training, after which the screws 5 are tightened. After this, the unit is sealed by filling the conductive elastosil 131-55 with gaps between the ends of the frames 12 and the surrounding stepped protrusions 10, as well as between the screw heads 5 and the wall 4. Filling is carried out by metered application of elastosil using a pneumatic doser D4 equipped with a 600 ml syringe flask and a set of needles with holes with a diameter of 0.37; 0.84 and 1.37 mm (production of NPP KVP Rainbow, Moscow).

The presence of distinctive features in the claimed device, namely:

- at the ends of the frames along their external and internal contours respectively contain enveloping and covered step ledges,

- the height of the covering step ledges is less than the height of the covered,

- elastic gaskets are located between the ends of the frames and the surrounding stepped protrusions,

- elastic gaskets are made of sealant, such as silicone,

- covering the stepped protrusions and (or) the ends of the frames are made with a slope,

- elastic gaskets are made of conductive sealant, for example elastosil 131-55,

indicates compliance of the claimed technical solution with the patentability criterion of "novelty."

The presence in the claimed method of manufacturing a radio electronic unit distinguishing features, namely:

- gaskets are placed after tightening the package,

- the gaskets are placed by filling with a sealant the gaps between the ends of the frames and the surrounding stepped protrusions, for example, by means of a metering device,

indicates the conformity of the claimed method to the criterion of "novelty."

At the same time, these distinguishing features ensure the achievement of a technical result — an increase in the reliability of the electronic block by increasing the efficiency of shielding the electromagnetic field, improving the tightness of the housing and reducing the magnitude of the transient electrical resistance between the parts forming the body (frames and walls). From this we can conclude that the proposed device and method of its manufacture correspond to the inventive step and do not follow directly from the modern level of science and technology.

The proposed electronic block has wide consumer demand and industrial applications, since the volume of production and use of electronic blocks, which are subject to increased requirements for reliable operation, is growing, for example, for communications equipment, computer systems, and avionics.

Claims (4)

1. An electronic unit containing a housing consisting of metal frames, elastic gaskets and two walls connected to the package by screws or studs, as well as printed units with detachable connectors, mounted on the aforementioned frames, characterized in that at the ends of the frames along external and internal contours contain respectively covering and covered stepped protrusions, while the height of the surrounding protrusions is less than the height of the covered, and elastic gaskets are located m forward ends of the framework and covering the stepped protrusions and made of a sealant, for example silicone. 2. The electronic unit according to claim 1, characterized in that the enclosing stepped protrusions and (or) the ends of the frames are made with a slope. 3. The electronic unit according to claim 1 or 2, characterized in that the elastic gaskets are made of conductive sealant, for example elastosil 131-55. 4. A method of manufacturing a radio electronic unit, including the manufacture of printing units, their fastening on a metal frame, placing elastic gaskets on the ends of the metal frames, assembling the metal frames and two walls in a bag and tightening the bag with screws or studs, characterized in that the elastic gaskets are placed after the package is pulled together by filling the gaps between the ends of the frames and the surrounding stepped protrusions with a sealant, for example, by means of a metering device.

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