Field device assembled with printed circuit board as screen for protection against effect of environment and against electromagnetic field/radio interference

FIELD: physics, control.

SUBSTANCE: present invention is related to electron field devices such as transmitters of technological processes parameters used for monitoring (routine inspection) of these processes. In particular, the present invention is related to electron field devices used in environment of technological plants, which may produce high level of electromagnet interference. Field industrial device (200) for operation under severe conditions comprises body (208) with electroconductive walls that surround cavity (206) with open end. Cavity may contain electronic module (292) based on printed circuit boards. Device comprises ready-fitted printed circuit board (270), which represents multilayer printed circuit board with through electric contacts and hidden layer (350) of grounding, which is electrically connected to body (202) for screening of electronic module (292) against electromagnet interference and provision of electronic module protection against effect of environment.

EFFECT: creation of body designs for transmitters of technological processes parameters, which possess improved resistance to effect of moisture and substances that pollute the environment, and also provide efficient filtration of electromagnetic field and radio interference.

30 cl, 9 dwg

 

The technical FIELD TO WHICH the INVENTION RELATES.

The present invention relates to electronic field devices like transmitters parameters of the technological processes used for monitoring (monitoring) of these processes. In particular, the present invention relates to electronic field instruments used in the environment of processing units which may have a high level of electromagnetic interference.

PRIOR art

Typically, electronic field devices (type transmitters of parameters of technological processes) are used for monitoring (monitoring) of technological processes, for example, at oil installations, installations for chemical processing, reprocessing of paper, biotechnological plants, plants for the pharmaceutical industry installations for the production of food products and beverages, etc. Transmitters parameters of the technological processes used to monitor, measure pressure, flow rate, the fluid or material in the tank, temperature, vibrations, etc. in Addition, the number of such field devices can be called electronic analytical equipment, electronic diagnostic equipment or other electronic devices for the current to the control over processes or even electronic, hydraulic or pneumatic actuators used for process control.

Transmitters of parameters of technological processes are usually placed inside the industrial premises, where they can be liquids, dust and moisture and various industrial pollutants. In some environments may be present process fluid type solutions of acids or alkaline solutions. Source of fluid can also be spray from hoses used for cleaning equipment. The liquid can drip or fall on the transmitter and the electrical contacts in the form of a spray or liquid dust. In addition, dust, moisture and liquids in the environment can contaminate and destroy both external and internal electrical contacts of the transmitter.

Specialists in the art known transmitters, electrical circuit which is placed in a hermetically sealed enclosure and protected by an outer cover. It is also known that the transmitters have one or more controllable switches for the adjustment of the circuit parameter of type zero adjustment or setting of the measurement interval. Typically, one or more switches or connectors field wiring only accessible after removing the cover of the transmitter.

Unfortunately, removing the outer cover is key leads to environmental pollution and electromagnetic and radio interference on the electronic circuit inside the housing of the transmitter. One method of protecting the electronic circuits inside the enclosure from EMFs is to place inside the transmitter conductive inner cover and providing frictional contact of the cover with the conductive walls of the enclosure to reduce the effects of EMF when it is removed. An example of the transmitter parameters of technological processes with the internal conductive cover is described in U.S. patent No. 5353200 "Transmitter parameters of technological processes with the internal conductive cover for shielding EMF" from October 4, 1994

The INVENTION

The technical task of the present invention is to provide a body structure transmitters of parameters of technological processes with improved resistance to moisture and chemicals, polluting the environment, as well as providing effective filtering of EMI and RFI. The present invention provides a solution of these and other tasks and has advantages relative to the nearest technical solutions.

The problem is solved by creating an industrial field device for use in harsh environments. Case industrial field device for use in harsh environments has a conductive wall surrounding a cavity with an open end. An electronic module on a printed square the tah is designed for placement within the cavity. Part of the electronic module on the PCB is the printed circuit Board Assembly, which is a multilayered printed circuit Board c interlayer electrical connections to the hidden layer of the ground connection electrically connected to the housing for shielding the electronic module on the printed-circuit from electromagnetic interference and protect the electronic module on the printed circuit boards from environmental influences.

In one embodiment, a multilayer printed circuit Board interlayer electrical connection is sized for placement within the body cavity of the device. Layer the ground, hidden in the thickness of the printed circuit Board, runs almost the entire area of the multilayer printed circuit Board. The grounding layer is electrically connected to the housing of the device for shielding electronic circuit inside the device from electromagnetic interference and ensure the protection of these electronic circuits from environmental influences.

BRIEF DESCRIPTION of DRAWINGS

The invention is further explained in the description of the preferred variants of the embodiment with reference to the accompanying drawings, in which:

Figure 1 depicts a General view of the field device according to the invention;

Figure 2 - field device to the printed circuit Assembly (longitudinal section), according to the invention;

Figure 3 - plot of the PCB in the bore, shown in figure 2 by the dotted line, according to the invention;

Figa diagram of the substrate of the printed circuit with many PCB Assembly (top view), according to the invention;

FIGU is a top view of one of the circuit boards in the collection presented on figa, according to the invention;

Figa - sectional view of the blind of the transition holes in a printed circuit Board Assembly according to the invention;

FIGU is a top view of the layer and ground layer interconnects with vias, shown by the dashed line 460 on figa, according to the invention;

Figa - section of the transition holes in a printed circuit Board Assembly according to the invention;

FIGU is a top view of the layer and ground layer interconnects with vias, shown by the dashed line 460 on figa, according to the invention.

In all cases listed in the description of examples of embodiments of the invention should be interpreted as a demonstration and not restrictive.

A DETAILED DESCRIPTION of the PREFERRED EMBODIMENT VARIANTS of the INVENTION

The present invention relates to the field of industrial device for operation in harsh conditions such as transmitter parameters of technological processes, which in the preferred embodiment, adnoidectomy electrical enclosure, providing protection from EMI and environmental influences even when removing the top cap the transmitter. Used in the phrase "industrial field device for use in harsh conditions" refers to the device housing, isolated from polluting the environment. In the preferred embodiment, in addition to housing, isolated from polluting the environment, the electronic circuit is additionally isolated from polluting the environment, as well as from electromagnetic and radio interference. In the preferred embodiment, to isolate the PCB Assembly from the environment used tight seal. Used in the description, the term "isolated" refers to a seal that has a leakage rate of helium is less than 5×10-8stands3(0,00000005 cubic centimeters of helium per second at a pressure of one atmosphere). Also used in the description of the term "EMF" or "Electromagnetic interference refers to interference from electromagnetic radiation, containing primarily electrostatic (electric field or field (E) energy at a frequency of between 0 Hz (DC) and about 10 GHz.

The present invention includes a printed circuit Board Assembly (CCA), used for electrical connection of the electronic circuits of the device with a field wiring and the local operator interface (LOI) or LCD display with a store who have field wiring apparatus. In addition, CCA has a secret for the ground layer, electrically connected with the conductive housing of the device for shielding electromagnetic interference. Layer ground CCA effectively divides the housing into two "Faraday cage" and serves as a screen for protection against environmental influences, and the screen EMF.

In General, the Faraday cage is an enclosure formed from conductive materials, designed to prevent transmission of electromagnetic waves inside this space and the outside. Transmitters of parameters of technological processes in the typical case are formed of conductive metal and are themselves cells Faraday. In fact, the external surface of the housing of the transmitter is an equipotential surface having essentially the same electrical potential at each point. The principle of the Faraday cage is that the charge on a charged conductor is always only on its outer surface. In the absence of any electric charge inside the structure, according to the Gauss law and the divergence theorem within an equipotential surface, there is no electrostatic field, even if the structure is exposed to an external field.

In manufacturing such conductive structures used throughout the world is to eliminate electric fields in the structure and protection of electronic circuits from unwanted electromagnetic signals. In the ideal case, the electric field and radio frequency cannot penetrate the Faraday cage and impact of the electronic circuit. However, it should be understood that the Faraday cage in the present invention are not ideal, as the body material (though conductive) is not an ideal conductor and, in addition, the enclosure is equipped with a hole for wiring in the building. In addition to moisture and other contaminants through the wiring in the electronic circuit inside the housing can penetrate (pass) interference (RFI) and electromagnetic interference (EMI). However, used in this description, the term "Faraday cage" refers to a conductive structure having the properties of a Faraday cage, which is sufficient for shielding the closed volume from external electromagnetic interference and radio interference.

Figure 1 shows the General view of the system 100 with transmitter parameters of technological processes according to the exemplary embodiment of the present invention. The transmitter 102 of parameters of technological processes connected with segment 104 of process tubes for measurement of the parameter or of the controlled process parameter associated with the fluid inside the segment 104 of the tube. The transmitter 102 is connected to the center 106 control via field wiring 108. Typically, field wiring includes power supply cable/for whom ellenia, and communication line. Field wiring 108 may include two or more transactions. In an alternative embodiment, the field wiring 108 provides power and ground, and the connection between the transmitter 102 and the center 106 of the control is carried out through the line wireless connection (not shown).

Typically, the transmitter 102 includes a housing 110 with a lid 112. The housing 110 is connected to the segment 104 of the pipe through the sealed base 114, which may include a flange or other fastening mechanism, provided by the consumer for the specific installation. On the housing 110 has an inlet 116 for the wiring that forms the input for field wiring 108 in the housing 110, and the connection of the electronic circuits inside the housing 110 of the transmitter with the center 106 of the control.

Printed circuit Board Assembly (CCA) 270 (figure 2) is located inside the housing 202 of the transmitter and has a secret for the ground layer which is in contact with the body of the transmitter at several points to circuit ground connection. CCA isolates the electronic circuit below CCA in the housing 202 of the transmitter, from electromagnetic interference and polluting the environment, in the case of removing the cover 208 of the transmitter.

Figure 2 shows a cut odnomodovogo enclosure according to the invention. In this example, the transmitter 200 is particularly the pressure sensor for measuring fluid pressure in a pipe or tank in the process. However, the transmitter 200 may represent an industrial sensor of any type.

The transmitter 200 includes a housing 202, which is connected with the base 204, the bounding an enclosed space 206 with a hole. Removable cover 208 has the size necessary to fit over the hole and protection confined space 206 from the environment. The housing 202 has an upper portion 210 and bottom portion 212. The upper portion 210 is threaded 214, which is made on the outer surface and has a size that is required to mate with the threads 216 on the inner surface of the cover 208. In addition, in the preferred embodiment, on the outer surface of the upper portion 208 is executed recess 218 having the size required to accommodate o-ring seals 220. The overhanging edge 222 of the cover 208 presses the annular seal 220 and isolates the housing 206 from the environment.

Usually the upper part 210 is connected with the bottom part 212 by means of welded connections 224 or other conductive means. The lower part 212 is connected to the base 204 by means of welded connections 226 or other conductive means.

Field wiring 228 passes through the hole 230 for the wiring in the upper part 210 of the housing 202. The connecting pipe 232 under the wiring has a body 234 with connecting sections 236 and 238. The housing 234 has a size that is required to mate with the corresponding recess 240 on the outer surface of the upper part 210 on the site, adjacent to the hole 230 for the wiring. The connecting section 236 is threaded for coupling with coupling nut 242 inside the housing 206. Between the coupling nut 242 and the inner surface of the upper part 210 through the connecting section 206 posted gasket 244 for protection confined space 206 around the hole 230. In another embodiment of the invention, the socket for the wiring or the receiving connection or molded socket can be welded or rigidly attached to the chassis directly.

Field wiring 228 is placed in the connector 246 wiring and nut 248 of the connector are connected by a thread with a connecting section 238 for fixing the position of the field wiring 228. In particular, since the nut 248 of the connector mounted on the connecting section 238, the flange 250 of the connector 246 wiring is pressed against the inner surface of the connecting section 238 and provide thereby fixing the position of the field wiring in the connector 246 wiring.

Confined space entry field 206 wiring 228 is divided into separate wires, including wire 252 earth connected with earthing lug 254, and the wire 256 power and signal wire 258, connected with spring-loaded electrical contacts 280, is accomplished by connecting the circuit Board 270. Backplane 270 easily accessible to the operator in the field after removal of the cover 208. Fee 262 local operator interface (LOI) is connected to the connecting circuit Board 270, and provides easy access to the elements of the field device, which must be available, including a push button 264 setting the measurement interval and a push button 266 zero adjustment to return the transmitter 200 in the initial state, and the switch 260 of the alarm system and switch 261 protect your account.

In this embodiment, the card 262 LOI fixed inside the upper part 210 of the housing 202 of the transmitter screws 268 and is separated from the printed circuit Board Assembly or wiring Board 270 supporting insulators 272 and the clamping ring 274. Clamping ring 274 is connected with the connecting plate 270, which, in turn, is associated with the seal 290. Threaded fasteners 288 pass through the clamping ring 274, the connection plate 270 and seal 290 in the lower portion 212 of the housing 202, fixing the position of the wiring Board 270. Typically, fasteners 288 may include bolts, screws or other threaded fasteners. In an alternative embodiment, fasteners 288 need not be threaded and may include fasteners of the type of pins, running the VI is tov etc.

Filter 278 to protect against radio interference (RFI filter)placed on backplane 270, provides a capacitive connection pin pin connector 280 field wiring layer 350 grounding and, consequently, the housing 202 of the transmitter. The RFI filter 278 is designed to filter radio interference, which can be distributed via the wiring 228, and, as a rule, to protect the electronic module on the printed-circuit from noise on the power lines.

Finally, the printed circuit Board Assembly (CCA or backplane) 270 in the preferred embodiment, consists of a multilayer printed circuit boards (WFP), covered by its edge conductive layer 282. Typically, CMP is made of insulating material such as ceramic, plastic and the like, which may be formed of conductive paths and the electrical interconnect.

As will be discussed in more detail below, the connecting Board 270 includes a hidden layer 350 grounding, which runs almost the entire diameter of the adaptor plate 270 and is connected to a conductive layer 282. The hidden layer 350 grounding is a planar layer that is hosted in the thickness of the CCA 270 and passing almost the entire diameter of the CCA 270. The hidden layer 350 grounding 350 is formed from a conductive material (such as copper) and is intended for electric with the organisations with the conductive walls of the housing 202 of the transmitter and shielded electronic module on the PCB from EMFs. In General, the electrical contact between the layer 350 ground and the housing 202 can be provided through the conductive layer 282, fasteners 288, conductive layer 282 on the edge or other means. In one embodiment, the seal 290 is electrically conductive, and channel ground is formed through the seal 290.

In the electrical connection layer to the grounding casing 202 270 CCA effectively divides the housing 202 into two Faraday cages (cage 284 Faraday over 270 CCA and cell 286 Faraday under the CCA 270).

In this embodiment, the inside of the lower portion 212 of the housing 202 CCA 270 is connected to the circuit Board 292 Assembly (CCA) of the transmitter through a flexible printed circuit 294. The connector 296 connects the flexible printed circuit 294 with CCA 270. Connector 297 connects the other end of the flexible circuit 294 with CCA 292 transmitter. In a preferred embodiment, between CCA 270 and a flexible circuit 294 is fixed to the radiator 295, providing channel heat sink for removal of heat released by any of the items placed on the flexible circuit 294.

CCA 292 transmitter placed inside the glass 298, with the influx of 300 that is designed to mate with the recess 302 in the lower part 212. The influx of 300 fixation of the position of the glass 298 in the lower part 212. The connector 304 connects the flexible circuit 306 with CCA 292 transmitter lower level, which, in turn, connects to the sensor 308 Yes the population through pin conclusions 310.

In the present embodiment, the sensor 308 pressure contains vitrified hole 312 for electrical pin conclusions 310. Vitrified hole 312 for supplying power goes up isolated from the environment sensitive membrane 314 adjacent to filled with oil cavity 316 inside the sensor 308. Filled with oil tube 318 connects the sensor 308 with a cavity 320, adjacent to the insulating membrane 322, which is connected with the process pipe.

The sensor 308 has a filling tube 324 to fill the cavity 316, tube cavity 318 and 320 oil to the required level. Air-filled tube 326 connects the sensor 308 with atmospheric vent hole 328, which allows the transmitter to measure gauge pressure.

Finally, the base 330 in the preferred embodiment, connected to the process tube by means of a clamp flange 332 and 334 provided by the consumer to pair with their specific technological device. Undercut 336 and 338 at the base 330 and the flange 334 have the size required to accommodate the spacers 340, providing a tight seal base 330 with flange 334.

Specialists in the art should be understood that the present invention can be used in combination with any type of sensitive element, not only is with the gauge pressure. In particular, the subject of the present invention CCA 270 can be used with any transmitter parameters of technological processes, provided that the thickness of the skin layer layer ground, hidden in the thickness of the CCA 270, will be sufficient for the effective isolation of electronic circuits from EMI, which can be distributed via the wiring 228 or come in from the surrounding production environment when removing the outer cap 208. In addition, the present invention can be used with any industrial unit, designed for operation in harsh environments, including distance measuring devices, wireless network interfaces, remote control, transmitters of parameters of technological processes, etc.

Figure 3 presents the incision CCA 270 and part assemblies with welded connection 224 between the upper part 210 and the lower part 212 of the housing 202 in an enlarged scale. As previously mentioned, the edge of the CCA 270 is covered with a conductive layer 282. Typically, 270 CCA is a multilayer substrate with a hidden layer 350 earth is made between the upper layer 352 and the lower layer 354. Typically, the top and bottom layers 352 and 354 and a layer 350 of the earth are parts of the multilayer printed circuit boards (CMP). As a rule, open planar surfaces 360 and 362 are water-resistant. However, in the process is izgotovlenie in the substrate are drilled hole, and the edges are trimmed for the formation of CMP 270. In these open edges on the surface are fibers that can act as capillaries and suck moisture into the layers 360 and 362 of the substrate. To prevent this phenomenon edge CMP 270 cover a conductive layer such as copper or tin, which also serves as a diffusion barrier for moisture and contaminants. In addition, each transition or mounting hole is exposed metallization.

As previously mentioned, the threaded fastening element 288 passes through the clamping ring, 274, 270 CCA and the gasket 290 in the lower part 212. The hole in the CCA 270, which receives the fastening element 288 threaded, also covered with a conductive layer 356 to prevent moisture from penetrating into the thickness of the card through the hole. Depending on the specific implementation layer 350 grounding may be subjected to etching to remove the layer 356 metallization of through holes and prevent zakolachivaniya to earth through the threaded fastening element. Alternative depending on the specific implementation layer 356 metallization can provide grounding for the layer 350 ground.

As mentioned above, the threaded fastening element 288 is mated with the formation of frictional contact with the lower conductive part 212 (and/or the upper part 210 of the body 202 and the conductive layer 364 PPM and electrically connected to Edinaya with a layer 350 of the ground through the conductive layer 356 or conductive layer 282 for shielding electronic circuit of the sensor (sensor type 308 figure 2) from EMFs.

In one embodiment, the seal 290 is an electrical insulator that prevents friction pairing CCA 270 with housing 202. Clamping ring 274 mates with the conductive path on the outer surface 270 CCA with the formation of frictional contact, while threaded fasteners 288 ultimately form a channel grounding to the chassis 202. If the seal 290 is electrically conductive (type commercially available pads for protection from EMFs), channel ground can be formed through the seal 290, and not through the threaded fastening element 288.

On figa presents a top view of a substrate 400 with many made it CMP 402. Usually, produce a multi-layer substrate 400, and then collect a trace, drilling, etching and metallization separate CMP 402 to create a finished PCB. In particular, PCB CMP 402 is cut out of the card path, for example along the line 404 Reza. Line 404 Reza is not continuous. CMP 402 is cut around the outline, except for a small jumper 406, which are secured CMP 402 in the plane of the substrate 400.

In CMP 402 form the openings 408 under fasteners, vias 410 for electrical contacts and through mounting holes 416 for components. The edge of the PCB (line 404 Reza) and openings 408, p is recognie holes 410 and through the mounting holes 416 for components cover the conductive layer 412. To help the operator to complete the installation using CMP 402, CMP 402 can be printed contours connector 414 and the text.

On FIGU presents a top view of CMP 402, similar to that shown figa, but on an enlarged scale. After mounting the components on CMP 402 this CMP is called PCB Assembly or CCA 402. After mounting the components of CCA 402 banging from the substrate 400, leaving the jumper 406, not covered with a conductive layer 412, ee edge. Electrical contact between the conductive layer 412 and the housing of the electronic device or transmitter, the frame 202 of the transmitter (figure 2), is sufficient to provide shielding of electronic circuits in the body from EMFs. In addition, the open jumper 406 on the circular area that is covered with a conductive layer 412, because of its small area does not create a significant problem, "capillary distribution of moisture and it can be covered with epoxy resin or similar material to further improve the moisture resistance.

For a complete solution for protection against capillary distribution of moisture line 404 cutting Board CMP can be carried out via the jumper 406 partial depth, so that the layer 350 ground and the bottom conductive layer 366 is fully remain open around the entire circumference of CMP 402 without any intervals or gaps. When applying the conductive layer 282 is and CMP 402 this conductive layer 282 covers the entire edge CMP 402 between layer 350 and a layer 366. This creates a complete diffusion barrier that prevents the penetration of moisture in the lower part of the housing through the WFP. It is important to note that the moisture penetrating through the remaining open edge of the CMP 402 in the field of carved lintels 406, penetrates only into the layer 352 CMP 402. The penetration of moisture into the layer 354 CMP 402 and thence into the lower part of the housing prevent the conductive layers 282, 350, 356 and 366 and the seal 290.

CCA 402 in addition to the holes 408 and transitional holes 410 includes contact pads 420 to create an electrical contact with a circuit element (not shown). The underlying electrical connectors 418, which can be laid on the inner layer of the card shown by the dotted line. Finally, to facilitate removal of heat from the electrical components mounted on CCA 402, or provide thermal connection with CCA 402 through the radiator 295, the fee is equipped with a special edge 422.

Finally, it is clear that the ground layer 2, 3, 5A, 5B, 6A and 6B), is virtually across the diameter (D) CMP 402. In certain areas of the layer grounding Vitruvian to prevent unwanted zakolachivaniya various conductive paths, pin conclusions electrical components and/or vias to the ground. In General, the size of the etched areas are doing as low as possible to prevent unwanted p is oscawana EMFs and/or diffusion of moisture through the layer of ground.

Specialists in the art it should be clear that CMP 402 may be given any desired shape. In the described embodiment, CMP is considered almost round in shape, but it may be square, elliptical, triangular or any other desired shape. In any case, the grounding layer is virtually over the entire area of SCP.

On figa shows a section of WFP 402. CMP 402 provided with a layer 430 of the ground connection electrically connected with the conductive layer 412 on the edge of the CMP 402. First MTG 438 passes from an open surface 428 of the upper circuit Board 434 from the field wiring to the etched region 436, which layer 430 ground was removed. The second transitional hole 440, displaced with respect to the first transition hole 438 passes from the etched region 436 to the open surface 426 of the bottom Board 432 from the sensor. In the first transition hole 438 deposited conductive layer 442 and the second transition hole 440 deposited conductive layer 444. The connector 446 closes the electrical circuit between the first and second vias 438 and 440. Thus, the circuit element 448 may be electrically connected with the circuit element 452 electrically connected through vias 438 and 440 without forming a direct path for prohozhdenie the pollutants from the field wiring through the CMP 402 to the sensor 456 and a flexible circuit 458. This special design can be called a design with the blind or biased transition hole.

Usually to create electrical contact without zakolachivaniya transient holes in the ground layer 430 grounding etched directly next to the vias 438 and 440 and the connecting line 446. A conductive mounting pad 466 is formed on the open surface 428-side field wiring and connect with the conductive layer 442 in the transition hole 438 using conductive paths 472 and pads 437 for transient holes. Circuit element 448 fixed to the mounting pad 466 using soldered connections 470. Similarly, a conductive mounting pad 468 formed on the open surface 426 from the sensor for mounting an electric component 452 using soldered connections 474. A conductive mounting pad 468 connected to a conductive layer 444 in the transition hole 440 via conductive paths 476 and contact pads 443 for transient holes. Despite the fact that the etched region 436 creates another defect in the Faraday cage, the limitation of the etched area of 436 square in the immediate vicinity of the vias and connectors can make the leakage EMF through the etched region 436 insignificant.

On FIGU p is redstavlena etched region 436 layer 430 ground on a plot of 460 PPM 402. First MTG 438, in which the deposited conductive layer 442 is thicker Board to the etched region 436, which layer 430 grounding 430 has been removed. The connector 446 connects the contact pad 439, electrically connected with the conductive layer 442 in the first transition hole 438, with the contact pad 441 for transient holes, electrically connected with the conductive layer 444 in the second transition hole 440. First MTG 438 and the second transitional hole 440 is shifted one relative to another to prevent a direct path for the passage of moisture and contaminants through the printed circuit Board.

Usually, the size of the etched region 436 doing the least possible in the preferred embodiment, equal to the amount sufficient only to accommodate the connecting line 446 and two vias 438 and 440 without zakolachivaniya elements on earth. In a preferred embodiment, the etched region has a maximum linear dimension of about 10 millimeters or less, to limit the amount of EMI and moisture, which can diffuse through the etched region 436.

Thus, the layer 430 grounding 430 serves as a screen EMF, and a screen to protect from moisture or exposure to the environment. In particular, the ground layer creates a path for the passage of EMFs in ARPUs, and the case of the transmitter creates a path for the passage of EMFs on the ground, shielding the electronic circuit under PCB 270 inside the body from EMFs. In addition, the conductive layer covering an edge of the printed circuit Board, prevents capillary distribution of moisture in the PCB, and the ground layer creates a diffusion barrier for moisture, so even if the moisture somehow bypasses the conductive layer and penetrates into the upper layer wiring Board, the grounding layer retains the moisture and prevents it from passing all the way through the connecting CCA 270 to the electronic circuitry below.

On figa presents the context of WFP 402 according to the embodiment of the present invention, where MTG 482 passes through CMP 402 in a straight line. CMP 402 provided with a layer 430 of the ground connection electrically connected with the conductive layer 412 on the edge of the CMP 402. MTG 482 passes from an open surface 428 of the upper circuit Board 434 from the field wiring to the etched region 436, which layer 430 ground was removed, and the open surface of the bottom Board 432 from the sensor. MTG 482 contains the first contact pad 437 for transient holes on the surface 428 and a second contact pad 443 for transient holes on the surface 426 and this through-hole is deposited conductive layer 442. Conductive layer 442 is electrically connected through the contact area 437 with the contact pad 443. For protection against environmental influences MTG 482 filled with solder 480.

Usually to create electrical contact without zakolachivaniya transition holes 482 to the ground layer 430 grounding etched directly next to the transitional hole 482. Electrically conductive mounting pad 466 is formed on the open surface 428-side field wiring and connect with the conductive layer 442 with conductive paths 472 and pads 437 for transient holes. Circuit element 448 fixed to the mounting pad 466 using soldered connections 470. Similarly, a conductive mounting pad 468 formed on the open surface 426 from the sensor for mounting an electric component 452 using soldered connections 474. A conductive mounting pad 468 connect with the conductive layer 442 with conductive paths 476 and contact pads 443 for transient holes. Despite the fact that the etched region 436 creates another defect in the Faraday cage, the limitation of the etched area of 436 square in the immediate vicinity of the transition holes 482 allows you to make the leakage EMF through CMP 402 insignificant.

On FIGU presents Vitruvian the I region 436 layer 430 ground on a plot of 460 PPM 402. Transient opening 482 in which the deposited conductive layer 442, passes through the entire thickness of the Board and through the etched region 436, which layer 430 grounding 430 has been removed. The size of the etched region 436 doing the least possible in the preferred embodiment, is brought to a value just sufficient to accommodate the transition holes 482 without zakolachivaniya conductive layer 442 on the ground. Pad 443 for transient holes shown by the dotted line, so as pads 437 and 443 for vias formed on exposed surfaces 426 and 428 Board for transient holes 438. In the case of offset vias, as shown in figv, pads for vias can be performed on the etched region 436 layer 430 ground and on exposed surfaces 426 and 428. Typically, pads, 437 (figa) and 443 for vias is slightly larger than MTG 482 (pigv) and made coaxially this hole (and pads 439 and 441 for vias on figv is slightly larger than the transient opening 440 and made coaxially this hole 440).

It is clear that the vias in the typical case are connected with the electrical components using connecting lines and pads. Resp is rste, having the size required for the placement of electrical wires or pin conclusions electrical components, can be larger and / or their size may vary. However, holes of all sizes in a printed circuit Board covered with a conductive layer as to prevent capillary distribution of moisture in the layers of the circuit Board, and an electrical channel that provides the interconnect electric element through cost. Depending on the particular implementation and/or type of contact holes can be offset (case "blind" holes) or to go through a charge in a straight line, as described above relative to the vias.

Used in this description, the term "end-to-end electrical contact" refers to an electrical contact or conductive path through the thickness of the Board. In the preferred embodiment, end-to-end electrical contact is intended to provide conductivity through the conductive channels or vias in a printed circuit Board, but does not allow the passage of unwanted moisture and other contaminants through the charge. End-to-end electrical contact can be made through the use of patterns with "blind transitional hole" (pigv) or structure with direct transition hole type (pigv).

Because the ku electric signals are transferred to the Assembly field wiring and transmitted through the CCA 270, the signal transmission through the CCA 270 to shielded electronic circuits can be carried out with simultaneous filtering EMI hidden layer 430 and ground delay substances polluting the environment, using CCA 270. Thus, the layer 430 grounding serves as a screen EMF, and a screen to protect from moisture or environmental diffusion barrier. In particular, the ground layer creates a channel for the passage of the EMF to the housing, and the housing of an electronic device creates a channel for the passage of the EMF to the ground and screens of the electronic circuit under the PCB inside the body from EMFs. In addition, the conductive layer covering the edge of the Board, prevents capillary distribution of moisture in the circuit Board, and the ground layer creates a diffusion barrier for moisture, so even if the moisture somehow bypasses the conductive layer and penetrates into the upper layer wiring Board, the grounding layer retains the moisture and prevents it from passing all the way through the connecting CCA 270 to the electronic circuitry below.

Specialists in the art it should be clear that CCA, which is the subject of the present invention may be manufactured using standard technologies CMP. You should also understand that the ground layer, hidden in the thickness of the CCA, which is the subject of this image is the shadow, must be thick enough to shield the electronic circuit of the sensor from electromagnetic interference. Depending on the interfering frequency, the thickness of the grounding system should be chosen to achieve the desired skin effect. "Skin effect" is that the distribution of high-frequency electric current in the thickness of the solid conductor, the current density near the surface of the conductor is greater than at its core. To use the principle of the Faraday cage for the ground layer should be thick enough to ensure the diffusion of high-frequency EMF in the case and their grounding and, therefore, isolation of the electronic circuits of the sensor and other electrical circuits from undesired electromagnetic and radio interference.

In the coating of the cut edges and hole-Board conductive material and increase the area of the coating layer of the ground to the maximum value, at which uncovered remains only a very small part of the area Board, CCA, which is the subject of the present invention, serves as a screen EMF, and a screen for protection against environmental influences. This allows you to use patterns of electronic devices with a single hole for access to the findings of the field wiring and the conclusions of the local operator interface (LOI) or LCD (LCD and only one cover, while protecting sensitive electronic circuits inside. In addition, if there is only one cover electronic device is smaller and more linear factor of the form.

Above the present invention is described with reference to preferred embodiments, however, experts in this field obviously, it can be amended in form and in detail, not beyond being and scope of the invention.

1. Field industrial device for operation in harsh environments, comprising a housing with electrically conductive walls surrounding the cavity having an open end; an electronic module on a PCB designed to fit within the cavity; and a printed Board Assembly, intended for electrical connection with an electronic module containing a multilayer printed circuit Board through the electrical contacts and the hidden layer to the grounding electrically connected to the housing for shielding the electronic module from electromagnetic interference and protect the electronic module from environmental influences.

2. Industrial device according to claim 1, characterized in that the printed circuit Board Assembly further comprises a conductive layer placed on the edges of the PCB and is designed to prevent PR is the origin of moisture through the edges of multilayer printed circuit boards.

3. Industrial device according to claim 2, characterized in that the conductive layer is electrically connected with the hidden layer of the ground, with printed circuit Board Assembly has a size that provides a conductive contact of the wall with edges for electrical connections from the hidden layer to the grounding body.

4. Industrial device according to claim 1, characterized in that it further comprises a removable outer cover intended for mounting with the possibility of removal on the body over its open end.

5. Industrial device according to claim 1, characterized in that it further includes filters for suppression of radio interference, connected to the circuit Board Assembly to protect the electronic module on the printed-circuit from noise on the power supply circuits.

6. Industrial device according to claim 1, characterized in that the printed circuit Board Assembly contains two or more printed circuit boards, a hidden layer of earth is placed between the two or more printed circuit boards; and a peripheral conductive layer placed on the edges of the two or more printed circuit boards and a layer of ground.

7. Industrial device according to claim 6, characterized in that two or more printed circuit Board made of insulating material and provided with vias and metal conductive paths formed on their surfaces to provide electrical magaizine the I.

8. Industrial device according to claim 1, characterized in that the ground layer contains conductive layer, passing almost the entire diameter of the PCB Assembly.

9. Industrial device according to claim 1, characterized in that it further comprises a seal placed between the printed circuit Assembly and electrically conductive enclosure walls.

10. Industrial device according to claim 9, characterized in that the seal contains vinyl seal, designed for electrical isolation of the circuit Board Assembly from the chassis.

11. Industrial device according to claim 9, characterized in that the seal contains a conductive seal, designed for electrical connections from the hidden layer to the grounding body.

12. Industrial device according to claim 9, characterized in that the seal and printed circuit Board Assembly to form a tight connection with the housing to protect the electronic module on the printed circuit boards from environmental influences.

13. Industrial device according to claim 4, characterized in that the outer cover is conductive, and the ground layer divides the housing into two Faraday cages, sufficient to isolate the electronic circuits inside the enclosure from electromagnetic interference.

14. Industrial device according to claim 1, characterized in that it further comprises a hole for the wiring on the part of the building, and uusee size, required for installation of field wiring, for connection of the device with the control system of technological process or monitor.

15. Industrial unit 14, characterized in that the field wiring is electrically connected to the circuit Board Assembly.

16. Industrial device according to claim 1, characterized in that the electronic module on the PCB contains the sensor parameter of the process used for monitoring (monitoring) process; and an electric circuit connected to the sensor parameter of the process.

17. Industrial device according to claim 1, characterized in that it further comprises an activation switch, placed in the upper part of the housing and electrically connected to the circuit Board Assembly for adjustment of the circuit parameter of the process.

18. Printed circuit Board Assembly for a field protected industrial device containing a multilayer printed circuit Board through the electrical contacts having a length required to fit within the cavity of the casing, the ground layer, hidden in the thickness of the printed circuit Board and passing almost the entire area of the multilayer printed circuit Board, electrically connected to the housing of the device for shielding electronic circuit inside the housing from electroma the magnetic interference and ensuring the protection of these electronic circuits from environmental influences.

19. Printed circuit Board for p, characterized in that it further comprises an electrical contact pads placed at least one exposed surface of the multilayer printed circuit Board having the size required for connection with electronic components.

20. Printed circuit Board Assembly p, characterized in that it further comprises a conductive layer placed on the edges of the multilayer printed circuit Board and designed to prevent the ingress of moisture through the edges of multilayer printed circuit boards.

21. A printed circuit Board according to claim 20, characterized in that the conductive layer is electrically connected with the hidden layer of the ground and the housing unit.

22. Printed circuit Board for p, characterized in that it further comprises a transitional hole formed in the multilayer printed circuit Board and passing in the thickness of the multilayer printed circuit Board at least one layer, and the hole limits the hole with walls covered with a conductive layer.

23. A printed circuit Board according to item 22, wherein the transitional hole filled with water-resistant material.

24. Printed circuit Board for p, characterized in that the ground layer contains conductive layer, electrically connected to the ground through the body of the device.

25. Transmitter for use in the process, to contain bus with conductive walls, surrounding the cavity having an open end, an electronic module designed for placement within the cavity; and a printed Board Assembly, intended for electrical connection with an electronic module containing a multilayer printed circuit Board through the electrical contacts and the hidden layer to ground, connected to the housing for shielding the electronic module on the printed-circuit from electromagnetic interference and protect the electronic module on the printed circuit boards from environmental influences.

26. The transmitter A.25, characterized in that it further comprises a removable outer cover intended for mounting on the housing over its open end.

27. The transmitter A.25, characterized in that it further includes filters for suppression of radio interference, connected to the circuit Board Assembly to protect the electronic module from noise on the power supply circuits.

28. The transmitter A.25, characterized in that the multilayer printed circuit Board contains two or more printed circuit boards, a hidden layer of earth is placed between the two or more printed circuit boards and conductive layer edges, placed on the edges of two or more printed circuit boards and a layer of ground.

29. The transmitter p, characterized in that two or more printed circuit Board made of insulating material and provided the us vias and metal conductive paths, formed on their surfaces to provide electrical misidentify.

30. The transmitter A.25, characterized in that the ground layer contains conductive layer, passing almost the entire diameter of the PCB Assembly.



 

Same patents:

FIELD: electricity.

SUBSTANCE: invention relates to electrical engineering and particularly portable shielded chamber design The invention may be used in research activities for assessing electromagnetic interference of different radio and electronic instruments. The side walls, top and bottom of the portable chamber are manufactured from current-conducting multi-layer corrugated material of "polymer film - current-conductive coating" type allowing for chamber stretching, compressing and smooth bending during installation at the working place. The content of multi-layer "polymer film - current-conductive coating"-Type material includes tape-like fragments absorbing electromagnetic radiation. The tape is manufactured from amorphous magnetic material.

EFFECT: reduction of chamber weight and cost, improvement of operation easiness due to avoidance of assembling and dissembling operations during chamber transportation from one room to another, preservation of required values of shielding effectiveness.

2 dwg

FIELD: physics.

SUBSTANCE: method of protection against electromagnet radiation emitted by electronic devices, for instance, from mobile phones, consists in application of protective facility that influences upon electromagnet waves, such as virgin gold in the form of at least one gold nugget or in the form of gold sand. Application of suggested invention is elimination or considerable reduction of electromagnet radiation effect at biological object by means of facility that accumulates natural radiations that are harmless for human being and suppresses unfavourable harmful radiations.

EFFECT: elimination or considerable reduction of electromagnet radiation effect at biological object.

6 cl, 1 tbl

FIELD: physics, computing science.

SUBSTANCE: invention is aimed at efficiency enhancement of protecting device application due to enhancement of its operational functionality within saving protective properties. This technical result is ensured due to that the device for protection of electronics from electromagnetic emission contains a cooled screen made of superconducting material, delivery system of cooling agent and closed cover with inner cavity for arrangement of electronics consisting of at least two layers connected with each other with cavity formation between layers for the cooling agent. At that time the superconducting material, forming screen is applied as a cover over one of the surfaces, and closed cover is made with possibility of access to the inner cavity.

EFFECT: efficiency enhancement of device application aimed at protection of electronics from electromagnetic emission.

3 cl, 3 dwg

FIELD: electromagnetic compatibility; electromagnetic field protection.

SUBSTANCE: material combining polymer base containing distributed particles of amorphous soft magnetic alloy Fe-Cu-Nb-Si-B or Co-Fe-Ni-Cu-Nb-Si-B of nanocrystalline structure and size from 1 to 100 micrometers according to invention, comprises of alloy particles containing nanocrystals of α-(Fe, Si) or ε-Co of volume density (0.6÷1.4)·10-5 1/nm3.

EFFECT: increased screening coefficient.

1 dwg

FIELD: supporting cable structures for fixing plurality of switchgear lead-in cables.

SUBSTANCE: proposed supporting cable structure for switchgear S incorporating switchgear cubicle accommodating power switch has supporting plate G with cable terminal surface FG. Provision is also made for first terminal board M1 that has terminal surface FM1 in essence identical with supporting plate G. First terminal board M1 can be joined with supporting plate G by means of at least two bolts B1, B2 so that lead-in cables L1, L,L2, L3, L4 running between terminal surfaces FG, FM1 of supporting plate and terminal board are disposed and fixed together to release tensile stresses. Two bolts B1, B2 are stud-bolts. One more terminal board M2 is also provided and connected to first terminal board M2 by means of bolts B3, B4. Other subject-matter of claimed group of inventions is use of supporting cable structure in switchgear S provided with switch-accommodating cubicle.

EFFECT: enhanced economic efficiency, facilitated installation and wiring.

6 cl, 2 dwg

FIELD: screening devices with screening cover.

SUBSTANCE: screening device contains screening cover, which covers electronic circuit positioned on electronic board, which cover has edge, divided by a gap from mounting side of electronic board, contact device, which is positioned in the gap and forms an electric connection between the screening cover and conductive contour on the electronic board, where leaves are formed on the edge of the screening cover, which leaves are used to mount the screening cover on the electronic board, and contact device is kept under resilient preliminary voltage, where contact device is made as a resilient packing element placed in the gap, which element absorbs electromagnetic waves.

EFFECT: improved screening device, increased efficiency of screening and ensured as low as possible costs of manufacture, in particular, manufacture of screening devices of given dimensions, which only cover certain sections of electronic board.

13 cl, 4 dwg

FIELD: radio electronics.

SUBSTANCE: proposed protective coating that can be used in developing and operating devices designed to confine electromagnetic radiation of instruments and to protect electronic equipment, information media, and biologic entities against high-level electromagnetic radiation has flexible film with surface impedance layer disposed on incident electromagnetic wave side. Film of first design alternate is made in the form of ribbon interwoven into reticular warp to form hold stitch in each cell; reticular warp cell width amounts to (0.1 - 1)λ, where λ is mean length of operating-range electromagnetic wave; reticular warp cell width, hold stitch radius, and film width are interrelated as follows: (0.8-1.5) : (1-2) : (0.6-2.7), respectively. Coating of second design alternate has embossed surface formed by uniformly alternating projections or cavities. Processes of multiple reflection of incident waves from embossed outer surface of coating are noted along with those of electromagnetic wave absorption caused by magnetic and electromagnetic loss in impedance layer of film. Transfer to new frequency band is attained by changing geometry of embossed outer surface basing on same type of film.

EFFECT: facilitated manufacture, enhanced efficiency of protection against electromagnetic radiation, reduced mass and size.

2 cl

FIELD: devices for screening of radio frequency.

SUBSTANCE: device contains frame (22) and lid (24), fastened to frame with possible detachment. Frame passes essentially around perimeter of electronic component. Frame has upper wall (36), side walls (38) branching from it, and a set of rigidity collars (50), passing from upper wall into internal space (40) of the frame. The lid has upper surface (54) and a set of elements (26) passing from it for engagement with side walls of frame. Lid and frame constitute a cover for screening electronic component from radio frequencies.

EFFECT: increased rigidity of device, reduced radiation or influx of high frequency signals from screening device.

3 cl, 7 dwg

FIELD: radio-electronic industry, namely, information transfer systems.

SUBSTANCE: device for protecting information transfer systems from interference, containing a screening element, additionally includes radio-absorbing device. This device consists of absorbing and packing elements, interconnected by horizontal surfaces. The other horizontal surface of the packing element of radio-absorbing device is located and held on internal surface of screening element, which is positioned above the horizontal surface of the body of information transfer system, which is mounted on electronic board. Radio-absorbing device is made with possible tight contact from the side of absorbing element with horizontal surface of the information transfer system body.

EFFECT: increased interference resistance of information transfer systems, simplified construction of protection device.

11 cl, 1 dwg

FIELD: the invention refers to radio-electronics.

SUBSTANCE: it may be used at constructing single-board radio-electronics blocks placing electro-radio-elements in the zones of analog and digital processing of signals connected between themselves by signal chains. The radio-electronics block has a multi-layer circuit board carrying printed conductors and electro-radio-elements grouped according to the zones of analog and digital processing of signals. The zones are screened with the aid of flat screens formed by situated in one of the inner conducting layers of terrestrial planes serving as conductors of feeding of the potential "Earth" for electro-radio-elements of their zones. The terrestrial planes are separated one from another with demarcation strip, deprived of metallization, passing along the frontier between the zones. The signal circuits between the zones are fulfilled with using of active buffer elements located in the inner conducting layer on the frontier between the zones. The configuration of the frontier line and spacing on it of active buffer elements is such that outlets "Earth" and "Feeding" and outlet signal outputs of the active buffer elements serving for transmission signals into the zone of analog processing signals and entrance signal outputs of the active buffer elements serving for transmission signals from the zone of analog processing of signals are in this zone and are connected with it correspondingly with its terrestrial plane, with the conductors of feeding of potential "Feeding", with inputs of electric circuits serving for reception of signals transmitted into this zone and with outputs of the electric chains serving for forming signals transmitted from this zone and the outputs of feeding "EARTH' and "Feeding" and outlet signal outputs of the active buffer elements serving for transmission of signals into the zone of digital processing of signals and entrance signal outputs of active buffer elements serving for transmission of signals from the zone of digital processing signals are in this zones and connected with it correspondingly with its earth plane, with conductors of feeding of the potential "Feeding", with inputs of electric circuits serving for reception of signals transmitted into the given zone and with the outputs of electric circuits serving for forming signals transmitted from this zone.

EFFECT: increases jamproof signal circuits.

3 cl, 9 dwg

Damped board // 2332817

FIELD: electricity.

SUBSTANCE: damped board contains printed circuit board and damping unit consisting of reinforcing layer made of structural material bonded with printed board by layer of viscoelastic material. Damping unit is performed as two-layer frame passing through fixing points of printed board and containing reinforcing layer and layer of viscoelastic material.

EFFECT: providing of printed boards damping with maximum saving of useful area; minimal increase of board mass and keeping damping properties in wide temperature range.

3 cl, 7 dwg

FIELD: electronics; printed circuit boards.

SUBSTANCE: multilayer printed circuit board consisting of signal dielectric layers comprising topological patterns of the printed wiring and interchanging with screening layers having the form of a grid provided with printed conductors reflecting the topological pattern configuration of their nearest signal layer. Top layers of said printed circuit board are covered with a protection coat that consists of a mixture of ferrite powder and plastic binder based on protective varnishes or compounds and is applied by means of spreading, immersion or spraying.

EFFECT: enhancement of the quality of printed circuit board protection against effects of EMI.

Electronic board // 2280967

FIELD: electronics, tool-making industry, namely, engineering of electronic boards.

SUBSTANCE: result is achieved because in electronic board as substrate the body of device is utilized, and conductive pattern is made of solder.

EFFECT: lower laboriousness and simplified manufacture of electronic boards, decreased losses during manufacture, possible processing of electronic board after expiration of service time.

FIELD: printed-circuit boards, multilayer conductors, and ribbon cables.

SUBSTANCE: proposed method involves spatial disposition of conducting communication lines which makes it possible to compensate for electromagnetic pickups in three-phase power circuits caused by self-induction and is based on compensating effect attained by superimposing electromagnetic inductances shifted in phase due to phase shift of currents carried by three adjacent conductors; novelty is that only positive (forward) currents carried by three adjacent layers and shifted in phase through 120 deg. are used in three-phase circuits. Passing three-phase current of same amplitude through three adjacent conducting tracks disposed strictly in parallel one on top of other in these three adjacent layers where columns built of conducting tracks occurring in three layers are formed we shall obtain equal-amplitude vectors in each layer using cyclic phase transfer; these vectors correspond to harmonic oscillations on vector diagram from all three phases (A, B, C).

EFFECT: maximized compensation of noise caused by self-induction.

4 cl, 3 dwg

FIELD: electronics.

SUBSTANCE: device has electronic boards block with radio-elements thereon and with radial grooves made in them, electric connectors of electronic boards and arc shields separating boards with sockets for bodies of radio-elements, connected to electronic boards by frame fixing, central bushing and rods. Along peripheral line of each arc shield slits are made, combined with radial grooves of each electronic board. Electric connectors of boards are made in form of shields curved around side surface for console portions of boards, current-conducting drawing of which is made in form of circular sectors, positioned between shields slits.

EFFECT: higher resistance to physical impact.

2 dwg

The electronic unit // 2234205
The invention relates to electronics and can be used in blocks of electronic equipment to improve cooling efficiency, in particular in the aviation lights - multi-function remote control

Electronic unit // 2233566
The invention relates to the field of electronic structures of blocks that can be used in miniature transceiver devices and control systems

Electronic unit // 2233565
The invention relates to the field of electronic structures of blocks used in missiles or portable launchers

The invention relates to the electrical industry in particular to thin film microelectronics

Electronic unit // 2224388
The invention relates to the field of electronic equipment, the design of electronic units, in which the electrical connection of printed circuit boards is carried out using electrical connectors without backplane

FIELD: electronics.

SUBSTANCE: device has electronic boards block with radio-elements thereon and with radial grooves made in them, electric connectors of electronic boards and arc shields separating boards with sockets for bodies of radio-elements, connected to electronic boards by frame fixing, central bushing and rods. Along peripheral line of each arc shield slits are made, combined with radial grooves of each electronic board. Electric connectors of boards are made in form of shields curved around side surface for console portions of boards, current-conducting drawing of which is made in form of circular sectors, positioned between shields slits.

EFFECT: higher resistance to physical impact.

2 dwg

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