MXPA99004027A - Shock-resistant electronic circuit assembly - Google Patents

Abstract

A shock-resistant electronic circuit assembly (10) is provided in which an electronic circuit is encased in an encapsulation (14) that engages a surrounding enclosure (18, 22) in shock-dispersing contact therewith. The encapsulation may have a plurality of edges (16, 16a, 16b), fins (24) or bosses (70) that bear against the enclosure. The encapsulation may include a shock-absorbing material (14f) disposed against the enclosure to protect the circuit against vibrations and a structural support material (14e) to protect the circuit against stress. The circuitassembly (10) may contain a capacitor (34) for storing an electrical signal and timing circuitry for releasing the stored energy after a predetermined delay. The circuit assembly (10) may be part of a transducer-circuit assembly (55) that includes a transducer module (58) for converting shock wave energy into electrical energy for the electronic circuit, and the released enregy may be converted into a detonation initiation signal. Assembly (55) may be part of a detonator (100) that receives a non-electric initiation signal and detonates following the delay determined by the electronic circuit. The detonator housing (112) or an optional sleeve (22) provides an enclosure for the assembly (55).

Description

ELECTRICAL CIRCUIT RESISTANT TO THE SHOCK DESCRIPTION OF THE INVENTION; This invention relates to encapsulated electronic circuits and in particular to assembled electronic assemblies or circuits and in particular to shock-resistant electronic circuit assemblies. Electronic timer circuits for firing detonators after a predetermined period of electronically controlled delay are known, the delay period is measured from the reception of the initiation signal which can provide power for a timer circuit. Thus, US Pat. No. 5,133,257 issued to Jonsson on July 28, 1992, presents an ignition system comprising a piezoelectric transducer that can be arranged next to a wick branch. When the wick detonates, a shock wave is imposed on the piezoelectric transducer which then produces an electrical pulse. The electrical energy of the transducer is stored in a capacitor that provides power to the timer. After a predetermined delay, the timer allows the remaining stored energy to the capacitor to trigger an ignition stroke on the detonator.

The initial ignition hit of the explosive material, thus giving the explosion in the detonator. Electronic delay circuits can be used to initiate bridge elements such as a semiconductor bridge as described for example in US 4, 708, 060 of Bickes granted on November 24, 1987 or a tungsten bridge as described in US 4, 976, 200 of Benson 11 December 1990. Other Electronic delay circuits are seen in Patents 5, 377,592 to Rodé and 3 January 1995, 5, 173 5S9 to Pallanck 22 December 199 and in 5, 435, 248 to Rodé July 25, 1995,. These patents generally suggest that the electronic circuitry be molded into a suitable plastic package causing a potting compound. See for example the Jonsson patent in column 2 lines 42 50 that of Pallanck in column 3, lines 32-35, that of Rodé in column 9, lines 30-33, that of Rodé ('248) column 7, lines 9-13. The stated purpose for such enclosures is to protect electronic components and minimize the likelihood of detonation or damage from mechanical impact. No particular configuration or typical material for such boxes is presented in these patents. The present invention relates to an electronic circuit assembly comprising an encapsulated electronic circuit that is dimensioned and configured to have cylindrically protruding portions. According to various aspects of the invention, the encapsulation can have a polygonal configuration or can be configured to define a plurality of tips protruding, or can be configured with protruding fins.

According to another aspect of the invention, the circuit assembly may comprise an uncoupling material and optionally a structural support material. The support material and the material may be each density; the deneity of the uncoupling material can be at least 20% less than the density of the support material.

In one embodiment of the invention, the electronic circuit may comprise a delay circuit comprising: i) storage means "having an input terminal for receiving and storing electrical energy; a switching circuit that connects the storage means to an output terminal to release the energy stored by the storage means to the output terminal in response to a signal from a timer circuit; - iii) a timer circuit operatively connected to the switching circuit to control the release by the switching circuit of the energy stored by the storage medium to an output terminal, the input terminal extends through the encapsulation to allow the delivery of electrical energy to the storage medium from outside the the capsule. The output terminal also extends through the capsule to send electrical energy from the storage means via the switching circuit to the outside of the capsule.

There may be an output initiation means operatively connected to the storage means through the switching circuit to receive via this circuit the energy stored by the storage means and to generate an explosive output initiation signal in response thereto. There may be a sleeve having an inner closure surface with a dimension and configuration suitable for receiving the delay circuit. The encapsulation or capsule engages the inner surface of the sleeve in a shock-scattering contact, as described herein. The invention also provides a transducer initiation unit comprising the circuit assembly, the sleeve and the output initiation means described above in combination with a transducer module comprising a bushing having suitable dimension and shape for coupling with the sleeve. The transducer module comprises a piezoelectric transducer in the bushing and a pair of transducer conduits connected to the input terminal of the circuit assembly. The invention also provides a delay detonator "comprising a enclosure or enclosure comprising at least one enclosure or enclosure closed at one end and open at the other for an extreme connection to an initiating signal means for providing an electronic initiation signal. to a shock resistant delay circuit assembly, as described. The delay circuit is in the box, and there is an output means disposed in the box in an operative relationship to the storage means, to receive via the switching circuit the energy stored by the storage medium and to generate an explosive output in the storage medium. answer to it. In one embodiment the delay circuit comprises a capsule with dimension and shape suitable for limited contact with an inner surface of the envelope, for example the capsule may have a cylindrically protruding configuration. In another embodiment the capsule may comprise a structural support material and a de-graft material, and optionally may be configured for limited contact with an inner surface of the envelope or closure. In a particular embodiment, the casing may comprise a sleeve disposed within the casing and the cassette may engage the inner surface of the casing. DESCRIPTION OF THE DRAWINGS Figure 1A is a schematic axonometric view of an encapsulated circuitry or module encapsulated in a moetrated circumferential envelope with dotted line according to an embodiment of the present invention; Figure IB is similar to Figure IA of an electronic module and shell according to a different embodiment of the present invention; Figure 2A is a schematic elevation view of an electronic module with another embodiment of the present invention; Figure 2B is a view of the electronic module of Figure 2A seen along line 2B-2B; Figure 2C is a schematic, partial cross-sectional view of the electronic module of Figures 2A and 2B disposed within a sleeve; Figure 3A is a perspective view of an electronic module according to another embodiment of the present invention; Figure 3B is a schematic cross-sectional view of the electronic module of Figure 3A and an envelope illustrating the protruding tips which engage the shell; Figure 4 is a perspective view, in partial cross section of a transducer delay initiation assembly comprising an electronic module and a sleeve of Figure 2C in conjunction with a transducer module; Figure 5A is a view similar to Figure 4 of an alternative embodiment of the invention; Figure 5B is a partial cross-sectional view of the transducer delay initiation assembly of Figure 5A taken along line 5B-5B; Figure 6A is a schematic sectional view partial transverse, showing a delay detonator comprising an encapsulated electronic circuit according to an embodiment of the present invention; and Figure 6B is a view, enlarged with respect to Figure 6A, of the isolation cup and change components of the detonator potential riser of Figure 6A. The present invention relates to a protective encapsulation for an electronic circuit arranged in a rigid enclosing envelope or enclosure such as a metallic shield. Preferably, at least part of the capsule is molded around the circuit before placing it in the enclosure, leaving only an access from the outside for cables to program, test and use the circuit, protecting it from environmental damage. The capsule of the present invention protects the circuit after it is in the enclosure by attenuating the "shock of the waves received by the envelope that could otherwise cause an effort that damages the circuit, particularly, which is believed, in the connections between circuit structures and interfaces of different density materials The capsule also protects the circuit by preventing the circuit from hitting the envelope. The capsule or encapsulation of the present invention can be physically configured to attenuate such waves of shock, and / or may comprise materials that attenuate such shock waves regardless of the physical configuration of the capsule, for example, the capsule can be physically configured so that, being arranged in the envelope or enclosure, it has limited contact with the capsule and confinement. The capsule then prevents the circuit from hitting the envelope as a result of vibrations or accelerations of short moments, and attenuates the shock wave received by the envelope because those waves can only reach the cirsuite through those portions of the capsule that they couple with the envelope. The rest of the encapsulation diffuses the shock wave and thus protects the circuitry. Alternatively the capsule may comprise a crash-reducing material that not only cushions the circuit against collision with the casing but also prevents the transmission of shock waves and vibrations from the casing, regardless of the degree of contact between the capsule and the casing. The hood may be sufficiently rigid to protect the circuit from damage by inadvertent bending as might occur during the manufacture of a device comprising a circuit or as a result of shock-induced acceleration of the circuit within a casing in a direction other than parallel to the axis of the envelope. In other words, the capsule provides a structural support for the circuit. Optionally, The capsule may comprise different materials that provide structural support and decoupling to vibration. The density, and preferably the hardness of the uncoupling material is typically less than the densities and hardnesses of the structural support material and the sheath coupled by the capsule. The density of the uncoupling material is preferably 20% less than the density of the structural support material and is preferably in a range of 20 to 60% lower, although in some cases the uncoupling materials of even lower densities can be used. Although the structural support material is separated from the enclosure or envelope by the uncoupling material, it is preferred that the structural support material be configured to disperse the shock waves from the enclosure. According to the above the structural support material can provide a circuit box configured so that its periphery defines a non-uniform displacement from the inner surface of the envelope. For example, a polygon box within a shell having a cylindrical inner surface will serve to dissipate the shock waves received from the shell even if the box is surrounded by an uncoupling material and does not directly engage the inner surface of the shell. Optionally, a capsule according to the present invention can have the two characteristics described, that is, it can be physically configured for a contact limited with a wrap and may comprise a material uncoupling from vibration. The invention demonstrates its utility in protecting any die circuit in a rigid enclosure that may be subject to physical vibrations or shock waves, but is preferably used to protect the electronic circuit of an electronically controlled detonator. Detonators made with electronic circuit assemblies according to the invention are less likely to be damaged by the prior detonation of the neighboring charges and will therefore detonate more consistently at the proper time than the detonators of the prior art. Since the wraps or enclosures provided by most of the detonators comprise cylindrical cases and optionally a cylindrical sleeve in the case, both of which provide a cylindrical inner surface, a capsule that is physically configured for limited contact with the wrapping may have any of a variety of non-cylindrical configurations mentioned herein and in the claims as cylindrical protruding configurations. A capsule with a cylindrical protruding configuration has an outer surface that only partially engages a cylindrical inner surface of a shell, leaving a portion of the encapsulation or capsule spaced from the inner surface of the shell. Some Examples of cylindrical protruding configurations are described in relation to FIGS. A to FIG. Typically an electronic detonator timer circuit comprises several integrated and different circuit elements including storage means such as a capacitor that receives and stores an electrical initiation signal. The delay circuit comprises an electronic switch circuit which can, upon receiving a trigger signal from a timer circuit, discharge the capacitor to an output terminal where the initiation element such as a hot wire, bridge wire or semiconductor bridge can be connected to the circuit. The trigger signal is provided by a timer circuit followed by a predetermined delay interval measured from the reception of the electrical initiation signal. Conventionally the timer circuit and the switch circuit are manufactured as an integrated circuit, and are used in conjunction with other separate circuit elements. The electronic circuit is typically assembled by arranging the circuit elements on a small portion of a printed circuit to provide the necessary electrical connections, using a so-called surface mount technology. Alternatively, the circuit elements can be mounted on a conductor structure as a lattice, which supports some of the connections between them. The capsule mold around the assembled circuit. Shown in Figure 1A is an encapsulated electronic circuit assembly according to an embodiment of the present invention, in which the encapsulation has shape and dimensions for limited contact with the surrounding wrapper. The circuit assembly 10 (sometimes referred to as "electronic module") comprises electronic circuit elements (not shown) mounted on a carrier 12 (e.g., an integrated circuit board, driver's frame, or the like which is indicated on a line The circuit assembly 10 also comprises a rectangular capsule 14 within which the circuit elements and the carrier are placed.Due to its rectangular polygonal configuration, the encapsulation 14 defines a plurality of cylindrically protruding longitudinally extending edges 16 which they can be coupled with the cylindrical inner surface of a closure shell such as an aluminum shield closed at the ends 18, shown in dotted line.The shield 18 contacts the edges 16 as long as the flat surfaces of the capsule remain distant from each other. the envelope as if it were circumscribed to a polygon outside the capsule 14. Due to the contac limited between the capsule 14 and the inner surface 18a, a shock wave received by the shield 18 can only chosar on the elements of sircuito after the dissipation by the encapsulation from the point of contact, for example, from the edge 16, as suggested by the wave dissipation lines 20. Preferably the capsule 14 is configured so that the points of contasto through The sural shock waves can be received propagate the shock waves at an oblique angle with respect to the carrier 12.

In an alternative configuration of "limited contact" shown in Figure IB, a circuit assembly 10a according to the present invention is disposed within a casing that projects a sleeve 22 open at the end that is insertable into a shield. The sleeve 22 is preferably formed of stainless steel and serves to protect the protective circuit 10a against external compressive forces. Figure IB also illustrates an alternative configuration for the capsule 14 'to provide more reduced contact between the capsule and the surrounding wrapper. Thus, the carrier 12 is disposed in a generally rectangular shape of encapsulation 14 ', but only the cylindrically peripheral protruding portions 14a, 14b at the opposite ends of the shell are sized and shaped to engage with the inner surface of the sleeve 2. Thus, the capsule 1 'is blown by the sleeve 22 along the pre-assembled edges 16a and 16b of the protruding portions.

Another embodiment of limited of the invention sontacto shown in Figure 2"A and 2B, which show the assembly circuit 10b comprising 14c capsule is configured to have a plurality of contact pads or fins 24 protruding cylindrically extending longitudinally beyond the circular periphery of the capsule 14c. As shown in Figure 2B or capsule encapsulation 14c is also configured to have formed therein imbricated 25. As explained, the imbricated 25 allow electrical test contacts or of "leads "for electrónisos circuits or pills inside sápsula 14c to be exposed while allowing the sontasto and remain within the profile of the capsule. thus, electrical contastos are acsesibles but not interfere with posicidn or suspension of encapsulation circuitry within the surrounding structure The circuit assembly 10b is designed so that the guides of outlet 57 and the initiation entry guides 56 protrude from opposite respective ends of the capsule 14c for connection with other devices, as will be described. Figure 2C provides a view showing how fins 24 establish only limited contact between 14c capsule and estrustura of rodeante casing such somo a sleeve 22 to estableser a space 48 between the rest of the periphery of the capsule 14c and sleeve -22. Lae waves The dissipation 20 illustrates how the fins 24 dissipate the shock waves A received from the sleeve 22. An encapsulation portion 14c is omitted from Figure 2C so that the electronic emission components 26 and the carrier 12 can be seen. No clutch another embodiment of limited encapsulated circuit electróniso of asuerdo with the present invention, sontacto illustrated in Figures 3A and 3B, which shows that the assembly circuit 10c comprises a 14d encapsulation is dimensioned and configured to have a shape protruding cilindrisamente due to the presensia of the tips 70 projecting from on the other hand cylindrical surface of the capsule l4d. The l4d capsule includes points 70 dimensioned and configured so that when inserted into a shell having a cylindrical inner surface, the tips 70 engage with the inner surface and in most, if not all, of the remaining outer surface of the capsule 14d is distanced from the inner surface of the envelope. The circuit assembly 10b comprises guides or conduits 56 (Figure 3A) projecting from the capsule 14d to allow the electrosurgical somponents to be operatively connected to the external electrical components. As seen in Figure 3A, the capsule 14d defines the overlaps 50 to provide access to the guides 52 without requiring the guides to protrude beyond the surface profile of the capsule 14d 1 as is the mode of Figures 2A, 2B, and 2C. Figure 3B illustrates the tips 70 that engage with the inner surface of a shell such as sleeve 22, and as indicated by the shock wave scattering lines, 72, will scatter the shock waves indicated at 74 that strike the shell. wrapping, that is, the sleeve 22, and which are transferred to the capsule 14d. A circuit assembly with a capsule according to the present invention can be used in a detonator to provide an electronically controlled delay in firing the detonator, which can operate by electronic or non-electrical signal means. For example, an electrical signal line can be connected to the input guides 65 (FIG. 3A) from a remote source controlled by a user to provide the initiation signal to a properly configured circuit assembly. Alternatively, the circuit assembly can be used with non-electrical signal initiation means, for example for one with a detonating cord, shock tube etc., provided that at least one transducer is provided to convert the non-electric initiation signal into an electrical signal that can be used to initiate the sirsuite assembly. The term 'initiation signal means "is used herein and in the claims, as meaning the inclusion of the electric initiation signal transmission lines as well as the non-electric initiation signal tranemission lines and their associated transducers to send an electrical initiation signal to the input guides of the circuit assembly of this invention. Figure 4 provides a perspective view of a transducer-circuit assembly. { or initiator-transducer) 55 comprising an electron module 54 comprising the circuit assembly 10b and the sleeve 22 of FIGS. 2A, 2B and 2C and an output initiation means 46. The cirsuite-transducer assembly 55 also comprises a transducer module 58 which Birve as part of an initiation signal transmission means for converting a non-electrically initiated initiation signal to an equates energy pulse to activate the electronic module 54. Various circuit components of the circuit assembly 10b such as a circuit integrated timer 28, a timer resistor 30, an integrated switch circuit 32, a storage capacitor 34, and an extractor resistor 36 are mounted in lattice somo portions of a carrier comprising a frame of connections or guides 40 and are disposed within the capsule 14C. The external initiation means 46 comprises a bridge element such as a semi-solid bridge 38 connected to output guides 57, an initiation charge 46a preferably comprising a second explosive material or a suitable substitute therefor such as tetramine-cls-bis (5-nitro-2H-tetrazolate N2) cobalt (III) perchlorate, certain primary explosives and energy mixtures such as zirconium potassium perchlorate, and a cassara or shielding of initiation 46b which is squashed in the neck region 44 and which stops the initiation twist 46a in a transfer relationship to the semi-solid bridge 38. The explosive exit initiation signal provided by the external initiation means may be used, for example to initiate the base charge or charge "ealida" of a detonator within which the assembly 55 is arranged, and may thus comprise part of the outlet means for the detonator, as described below with reference to Figure 6A. The capsule 14c couples the sleeve 22 (see Figure 2C) only to the aletae (which are not visible in Figure 4) and thus establishes a space 48 between the capsule 14c and the sleeve 22. As indicated, the capsule 14c defines imbricadoe 50 where test guides or program 52 can access through the cap 14c, so that the circuit can be programmed and / or tested before assembling the detonator. Impregners 50 preferably allow the guide to remain within the surface profile of the capsule 14c, that is the guides preferably do not extend into the space 48, to make contact with the surrounding wrapper. Thus, the electronic module 54 can be inserted in the sleeve 22 and the guides 52 do not come into contact with the sleeve 22. The transducer module 58 Figure 4) comprises a piezoelectric transducer 60 and two transfer guides 62 arranged in a transducer plug 64. Upon receiving a shock wave, the transducer 60 produces an electrical pulse that is sent to the circuit assembly 10b via the transfer guides 62 and the impulse guides 56. The transducer bushing 64 is dimensioned and configured to couple the sleeve 22 so that the transducer module 58 can be fixed on it. end of the sleeve 22 with the guides 62 in contact with the pulse guides 56. The electronic module 54, the sleeve 22 and the transducer module 58 have a dimension and shape so that, when assembled as shown in Figure 4, it produces a space at 66 between the electron module 54 and the transducer module 58. In this way the electronic module 54 is at least partially shielded against the shock wave which causes the l Piezoelectric transducer 60 from origin to electric pulse for circuit assembly. The pressure imposed by such a shock wave is transferred through the transducer module 58 to the sleeve 22, as indicated by the force arrows 68, rather than the electronic module 54. Figures 5A and 5B illustrate a delay initiation assembly. 55a traneductor according to a alternative embodiment of the invention wherein the capsule for the electronic circuit is not configured for limited contact with the envelope. In this embodiment the capsule comprises a box or housing for the electronic components and the carrier. The box l4e comprises a structural support material and a decoupling material 14f. Generally, the structural support material of box 14e must have a Young's modulus of at least 5 x 10 * pounds per square inch and preferably a Young's modulus in the range of about 1 x 105 to 40 x 10 4 pounds per square inch, preferably The structural support material has a strength of at least 5000 pounds per square inch (5000 x 0.07 = 350 kg / cpr1) and a thermic expansion component that are the same as the integrated circuit components. The box 14e may comprise, for example, an epoxy box filled with l4e glass "Which, when cured, has a density of at least 1 gram per cubic centimeter and a Young's modulus of 1 x 10 pounds per square inch. Such epoxy material is obtainable from Sumitomo Corporation under the name Resin No. 6300 and it is indicated that it is 60% filled with glass. The box 14e is sufficiently rigid when cured to provide structural support to the cirsuito and help prevent damage to the sirsuite by inadvertent bending. As seen in Figure 5A, the sau 14e has a generally rectangular sonfiguration and is configured to have sides 27 of which the guides 5 protrude. to prevent the guides 52 from leaning against the electrically conductive sleeve 22 and short circuiting the electronic circuit there, the box 14e is configured to define displacements 71 protruding from the sides 27 of the case 14e more "than the guides 52 Thus, if the box 14e comes into contact with the sleeve 22 during assembly, the displacements 71 will prevent the guides 52 from engaging the inner surface of the sleeve 2. The box 14e may have dimensions and shape for a longitudinal length limited to the inner surface of the sleeve 22 as described above, for example in relation to Figures 1l and 1B, but the box 14e preferably has dimensions and shape as suggested in FIG. Figure 5B so that when centering inside the sleeve 22, do not make direct contaste with the inner surface thereof. In the illustrated embodiment, the space between the box 14e and the sleeve 22 is basically completely filled by an uncoupling shock-absorbing material I4f from the encapsulation. In a particular embodiment of the invention the uncoupling material 14 f has a density of only 0.8 gcc and a Young's modulus of 350 kg / cms and thus differs from the epoxy box filled with glass 14e. The uncoupling material may comprise an elastic polymeric material, for example, a silica and may optionally be formed as a foam. He Uncoupling material comprises a mound of foam mooring «which can adhere to the box 14e to engage with the inner surface of the sleeve. However, it is expected that a more suitable method for applying the uncoupling material of the encapsulation between a structural support material and the envelope, will comprise injecting polymeric uncoupling material into foam in the space between them, this is the space between the epoxy box and the sleeve 22. The uncoupling material between the sleeve and the circuit inside the capsule eirve to attenuate the force of the shock waves that can transmitiree from the surroundings of the cirsuito, thus protecting the circuit. This protective effect is achieved without the need to limit the contact between the uncoupling material 14 f and the interior of the wrapper, but the protective effect is improved when the uncoupling material is physically configured for limited contact with the wrap as described in the Figures. ÍA - 3B. The protective function of the encapsulation is further improved, because the sack 14e has dimensions and shape that define a non-uniform displacement from the cylindrical interior surface of the sleeve 22. Specifically the box I4e, is basically rectangular and is therefore cylindrically protruding even when not directly engaging the inner surface of the sleeve 22. According to the above, for example, the distance between an edge of the box 14e and the inner surface of the sleeve 22, represented as displacement SI, is notably shorter than the distance between a point on the side of the box 14e and the inner surface of the sleeve 14c, represented by S2. The remnants of the shock wave received by the case 14e will be dissipated by an irregular pattern in respect to the sleeve 22 before they find the circuit there. Other cylindrical protruding configurations for the case I4e can also improve the protective function of the capsule. Referring now, a digital delay detonator comprising a circuit assembly according to one embodiment of the present invention is shown in FIG. 6A. The delay detonator 100 comprises an initiation signal means comprising a non-electric input transmission line having, in the illustrated case, a shock tube 110, adapter bushing 114, insulation cup 118, load lifting potential 120 and transducer module 58. As is well known to the technicians, the shock tube comprises a hollow plastic pipe, whose inner wall is covered with an explosive material so that when ignited, a low energy shock wave propagates , through the tube. See for example, Thureson, U.S. Patent 4, 607, 573 (it is to be understood that other non-electrical signal transmission lines can be used, such as rope detonating, low energy detonating cord, low speed shock tube and the like, instead of the shock tube). The shock tube lio is attached to the open end 112a of a casing comprising a housing 112 by an adapter bushing 114 around from which the crushing 116, 116a is crushed. The bushing 114 also helps to form an environmental protective seal between the housing 112 and the outer surface of the shock tube 110. The case 112 is made of an electrically conductive material, usually aluminum, and preferably of a shape and size of the primers conventional, that is, detonators, a segment 110a of the shock tube 110 within the housing 112 ends at the end 11Ob in close proximity to, or in contact with, an anti-static insulating cup 118. The insulating cup 118, as best seen in FIG. the figure 6B, is of a type well known in the art and is made of a semiconductive material, for example of a polymeric material filled with carbon, to form a path to the housing 112 to dissipate any static electrics that. It can pass through the shoke tube 110. See for example Gladden U.S. 3,981,240. A low energy potential augmentation twill 120 is placed adjacent to the insulating cup 118 and in a signal communication relationship with the end 110b of the shock tube 110. As best seen in Figure 6B and is well known in the art. technical, insulating cup 118 comprises a generally cylindrical body (usually in the form of a truncated cone disposed with the larger diameter towards the open end 112a of the housing 112), the interior of which is divided by a thin rupturable membrane 118b within an inlet chamber 118a and a chamber of exit 118c. The end 110b of the shock tube 110. { Figure 6A can be received inside the entry chamber 118a (the shock tube 110 is not shown in Figure 6B, to improve the clarity of the illustration). The outlet chamber 118c provides an air space between the end 110b of the shock tube 110 and the potential increase load 120. When operating, the shockwave signal travels through the shock tube 110 breaking the membrane 118b and through the space provided by the exit chamber 118c and crashes into and dunes the potential increase load 120. The potential increase load 120 comprises a small amount of explosive 124, on which a first cushion element 126 is deposited. The explosive 124 comprises a first explosive such as lead azide, but can understand a second suitable explosive, for example BNCP. A first cushion element 126, annular in good shape for a central thin membrane, is disposed between the insulation cup 118 and the explosive 124 to withstand the attack pressure with which the explosive 124 is pressed during the manufacture of the detonator 100, to protect the exploive 124 against the direct application of pressure. The insulation cup 118, the first cushion element 126, and the potential increase load 120, may conveniently be adjusted in a potential increase shield 132 as shown in Figure 5B. The outer surface of the insulation cup 118 is in conductive contact with the inner surface of the shield 132, which in turn is dimensioned and configured for a frictional fit with the interior of the housing 112, thus providing a path of electrical conductivity of the shock tube 110 to the case 112. In general, the potential increase shield 132 is inserted into the housing 112 and the housing 112 is squashed to retain the shield 132 as well as to protect the contents of the housing 112 against the environment. A non-conductive buffer 128, having a thickness of 0.015 inches 0.038 cm) is located between the load 120 and the transducer module 58 to electrically isolate the transducer 58 from the load 120. The module 58 comprises a piezoelectric transducer which is disposed in a force communication relay with the load 120 and so can convert the output force of the load 120 to a pulse of electrical energy. The output guides of the module 58 are connected to the module 54 as shown in Figure 4. As illustrated in Figure 5, the envelope provided by the The detonator 110 comprises the housing 112 and an optional open-ended steel sleeve 22 which thus envelops the electron module 54 and which is configured to have a friscid fit are the interior of the housing 112. The detonator 100 comprises a means of output to produce a knock output signal at the end of the delay interval. As indicated, part of the detonator exit means comprises an electronic module departure means 46 (shown in Figure 4) adjacent to which in the detonator 100 there is a second cushion element 142 which separates the means of output initiation of the electronic module 54 from the remainder of the detonator output means, comprising the output charge 144 disposed at the closed end 112b of the housing 112. The output charge 144 comprises an optional primary explosive 144a (for which a second explosive material). suitable, for example BNCP can be replaced) and a secondary explosive 144b. This 144b has sufficient shock power to break the housing 112 and detonate the explosives of potential increase, dynamite etc. disposed in the vicinity of the signal transfer to the detonator 100. When used, a signal of non-electrical initiation in the medium of Initiation signal travels through the shock tube 110 and is emitted at the end 110. The rupture membrane by signal 118b of the isolation cup 118 and the first cushion element 126 for initiating the explosive 124 of the potential increase load 120. The explosive 124 generates a detonation shock wave that leads the piezoelectric transducer to the transducer module 58. The transducer module 58 then produces a pulse of electrical energy which is received by the electronic module 54. Thus the non-electric initiation signal means sends an initiation signal to the circuit assembly of the electronic module 54. The circuit assembly stores the pulse of the electrical energy and after a predetermined delay releases or transports the energy to the output initiation means which initiates the output charge 144. As indicated above, in alternative embodiments, the encapsulated circuit of the present invention can be used is an electric detonator delay circuit designed for use with an electrical signal transmission wire instead of a shock tube or other transmission line non-electrical signal. In such a circuit, of course, there would be no need for a potential increase load 120 or a transmission module 58. Although this invention has been described in detail with reference to a particular embodiment thereof, it is apparent that reading and the understanding of the above, gives technicians idea of numerous variations to the described modalities. For example, it is noticeable that even if the envelope or enclosure does not have a cylindrical interior surface, the configuration of the encapsulation of the circuit can be adapted to limited contact.

Claims (13)

1. - A shock-resistant electronic circuit assembly comprising a rigid envelope having an inner surface and an electronic circuit therein encased in an encapsulation within the envelope, the encapsulation is molded around the circumsuit and has dimensions and shape for limited contact with the inner surface of the envelope.

2. - The circuit assembly according to claim 1, wherein the enclosure has a cylindrical interior surface and wherein the encapsulation or capsule has a generally polygonal configuration that provides limited contact with the interior surface.

3. The circuit assembly according to claim 1, wherein the baffle has an inner surface and wherein the capeula has an outer surface and is configured to define a plurality of tips or nipples protruding from the outer surface of the cap. capsule and that provide limited contact with the inner surface.

4. - The circuit assembly according to claim 1, wherein the enclosure has a cylindrical inner surface wherein the capsule is configured to define fins that extend longitudinally and It provides a limited contact with the inner surface.

5. - A shock-resistant elestronic circuit assembly comprising an electronic circuit arranged within a confinement comprising a siliceous inner surface and which is enclosed in a capsule comprising a structural support material that encloses the circuit and is configured for leaving a space between the structural support material and the inner cylindrical surface of the enclosure or envelope, and further comprising an uncoupling material that engages with the inner surface and which is placed in the space between the structural support material and the inner cylindrical surface of the confinement, the uncoupling material has a deficiency of at least 20% less than the density of the structural support material.

6. - Asiento circuit assembly are claim 5, wherein the electronic circuit comprises a delay circuit that has: i) storage media connected to an input terminal to receive and store electrical power; ii) a switching circuit that connects the storage medium to an output terminal to release energy stored by the storage medium to the output terminal in response to a signal from the timer circuit; iii) the timer circuit is operatively connected to the switching circuit to control the release by the switching circuit, of the energy stored by the storage means, to the initiating element; wherein the inlet terminal extends through the sachet to allow the delivery of lasers energy to the massaging means from the outside of the capsule; and wherein the output terminal extends through the capsule to send electrical energy from the storage medium via the switching circuit to the outside of the capsule.

7. - The circuit assembly according to claim 6, in combination with an output initiation means operatively connected to the storage means to receive via the switching circuit the energy stored by the storage means and to generate a signal of explosive exit initiation in response to that, and wherein the enclosure or enclosure comprises a sleeve having an inner enclosing surface and having dimensions and shapes for receiving the delay circuit assembly therein.

8. - A transducer assembly unit that comprises the gangway circuit according to claim 7, a transducer module comprising a bushing 1 that is dimensioned and configured to couple with the bushing, a piezoelectric transducer in the bushing and a pair of transducer guides that goes to the bus terminal. circuit entry.

9. - A delay detonator comprising a confinement comprising at least one housing closed at one end and open at the other for connection a. a means of initiation signal, the enclosure has an interior surface; a circuit assembly according to claims 1, 3 or 4 arranged in the housing; the initiating signal means fixed at the open end of the housing to provide an electrical initiation signal to the circuit assembly wherein the electronic circuit comprises a delay circuit having i) storage means connected to the initiating signal means for receiving and storing electric power from the initiating signal means ii) a switching circuit that connects the storage medium to an output terminal to release energy stored by the storage medium to the output terminal in response to a signal from the timer circuit; L iii) the timer circuit is operatively connected to the switching circuit to control the release by the switching circuit, of the energy stored by the storage means, to the start-up element, means of output, discharges in the housing in operative relation to the medium of storage through the switching circuit to receive by this switching circuit, the energy stored by the storage medium and generate an explosive output in response to it.

10. - A delay detonator comprising: a confinement comprising at least one housing closed at one end and open at the other for connection to an initiating signal means, the enclosure has an interior surface; an initiation signal means fixed at the open end of the housing to provide an electrical initiation signal to the circuit assembly wherein the electronic circuit comprises a delay circuit having i) storage means connected to the initiation signal means for receiving and storing electrical energy from the initiating signal means ii) a switching circuit "which connects the storage medium to an output terminal to release energy stored by the storage medium to the output terminal in response to a signal from the timer circuit; iii) the timer circuit is operatively conested to the switching utility to control the release by the switching circuit of the energy stored by the storage means; iv) a capsule that encapsulates the elements i), ii) and ÜL) and that engages with the inner surface of the enclosure; and outlet means die in the box in an operative relay to the storage means through the switching circuit to receive by the switching circuit the energy stored by the storage medium and to generate an explosive output in reepueeta to it, where the capsule comprises a structural support material which encapsulates the tissue within the housing and which is configured to leave a space between the structural support material and the inner surface, the capsule further comprises a material uncoupling in space and coupling with the surface inside.

11. The detonator according to claim 10, wherein the uncoupling material and the support material Each structure has a density and the density of the uncoupling material is at least 20% less than the density of the structural support material.

12. The agreement detonator is claim 10 or 11 wherein the capsule has dimensions and shape suitable for limited contact with an inner surface of the enclosure.

13. - The circuit assembly according to claim 5, wherein the capsule is dimensioned and configured to have cylindrical protruding portions. 1 . - A chocque-resistant electronic circuit assembly comprising an elastomeric cirsuite encapsulated in a capsule that is dimensioned and configured to define protruding fins, the circuit is disposed within a rigid enclosure having an inner surface, with the capsule having a limited contact with that inner surface. 15. - A cirsuite assembly comprising an electronic encapsulated circuit e? a capsule which is dimensioned and configured to have cylindrical protruding portions, wherein the eclestronic cirsuite comprises a delay cirsuite having i) storage means conestate to an input terminal for receiving and storing energy 7 electric; ii) a switching circuit that connects the storage medium to an output terminal to release energy stored by the storage means to the output terminal in response to a signal from the timer circuit; iii) the timer circuit _ is operatively connected to the switching circuit to control the release by the switching circuit, of the energy stored by the masking medium, to the initiating element; wherein the input terminal extends through the capsule to allow the delivery of electrical energy to the storage medium from outside the cabinet; wherein the outlet terminal extends through the capsule to send electrical energy from the storage means by the switching servo to the outside of the capsule; the assembly further comprises an exit initiation means operativelycontacted to the masking means and to generate an explosive output signal in response thereto, and a sleeve having an inner closure surface dimensioned and configured to receive the circuit assembly of delay there, in where the capsule engages with the inner surface of the sleeve in a shock-scattering contact. 16. - A circuit assembly comprising an electronic circuit encapsulated in a capsule that is dimensioned and configured to comprise cylindrical protruding portions, wherein the electronic circuit comprises a delay link that comprises: i) storage means are shown to a terminal entry to receive and store electric power; ii) a switching circuit that connects the storage medium to an output terminal to release energy stored by the storage medium to the output terminal in response to a signal from the timer circuit; iii) the timer circuit is operatively set to the switching utility to control the release by the switching circuit of the energy stored by the storage means to the initiating element; wherein the input terminal extends across the capsule to allow the sending of electrical energy to the storage medium from the outside of the capsule; where the exit terminal extends to through the capsule to send electrical energy from the storage medium through the snuffer ring to the outside of the capsule; wherein the capsule comprises a structural support material and an uncoupling material, wherein the density of the uncoupling material is at least about 20% less than the density of the structural support material. 17. A delay detonator comprising: a confinement comprising at least one housing closed at one end and open at the other end to be set to an initiation signal means, the enclosure has an interior surface; a circuit assembly according to claim 6 in the housing; The initiating signal means is fixed at the open end of the housing to provide an electrical initiation signal to the circuit assembly, wherein the electronic circuit comprises a delay circuit having: i) storage means connected to an input terminal to receive and store electric power; ii) a switching circuit that connects the storage medium to an output terminal to release energy stored by the storage medium to the output terminal in respueeta to a signal from the timer circuit; iii) the timer circuit is operatively connected to the switching circuit to control the release by the switching circuit, of the energy stored by the storage means, to the output means; and output means disposed in the housing in operative relation to the storage means through the switching circuit to receive the stored energy via the switching circuit and generate an explosive output in response thereto. 18. - The detonator according to claim 17, wherein the hood is dimensioned and configured for a limited contact with an interior surface of the enclosure. 19. - The detonator according to claim 18 wherein the inner surface of the enclosure has a cylindrical configuration and wherein the capsule has a configuration with cylindrical protuberance.