WO2021233823A1 - Ensemble broche de contact à ressort, ensemble carte de circuit imprimé comprenant un circuit de temporisation, et procédés correspondants - Google Patents

Ensemble broche de contact à ressort, ensemble carte de circuit imprimé comprenant un circuit de temporisation, et procédés correspondants Download PDF

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Publication number
WO2021233823A1
WO2021233823A1 PCT/EP2021/062985 EP2021062985W WO2021233823A1 WO 2021233823 A1 WO2021233823 A1 WO 2021233823A1 EP 2021062985 W EP2021062985 W EP 2021062985W WO 2021233823 A1 WO2021233823 A1 WO 2021233823A1
Authority
WO
WIPO (PCT)
Prior art keywords
contact pin
spring
guide bushing
housing
circuit board
Prior art date
Application number
PCT/EP2021/062985
Other languages
English (en)
Inventor
Benjamin DONAUER
Original Assignee
DynaEnergetics Europe GmbH
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by DynaEnergetics Europe GmbH filed Critical DynaEnergetics Europe GmbH
Publication of WO2021233823A1 publication Critical patent/WO2021233823A1/fr

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Classifications

    • E—FIXED CONSTRUCTIONS
    • E21—EARTH OR ROCK DRILLING; MINING
    • E21B—EARTH OR ROCK DRILLING; OBTAINING OIL, GAS, WATER, SOLUBLE OR MELTABLE MATERIALS OR A SLURRY OF MINERALS FROM WELLS
    • E21B43/00—Methods or apparatus for obtaining oil, gas, water, soluble or meltable materials or a slurry of minerals from wells
    • E21B43/11—Perforators; Permeators
    • E21B43/116—Gun or shaped-charge perforators
    • E21B43/1185—Ignition systems
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01R—ELECTRICALLY-CONDUCTIVE CONNECTIONS; STRUCTURAL ASSOCIATIONS OF A PLURALITY OF MUTUALLY-INSULATED ELECTRICAL CONNECTING ELEMENTS; COUPLING DEVICES; CURRENT COLLECTORS
    • H01R12/00—Structural associations of a plurality of mutually-insulated electrical connecting elements, specially adapted for printed circuits, e.g. printed circuit boards [PCB], flat or ribbon cables, or like generally planar structures, e.g. terminal strips, terminal blocks; Coupling devices specially adapted for printed circuits, flat or ribbon cables, or like generally planar structures; Terminals specially adapted for contact with, or insertion into, printed circuits, flat or ribbon cables, or like generally planar structures
    • H01R12/70—Coupling devices
    • H01R12/71—Coupling devices for rigid printing circuits or like structures
    • H01R12/712—Coupling devices for rigid printing circuits or like structures co-operating with the surface of the printed circuit or with a coupling device exclusively provided on the surface of the printed circuit
    • H01R12/716—Coupling device provided on the PCB
    • H01R12/718—Contact members provided on the PCB without an insulating housing
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01R—ELECTRICALLY-CONDUCTIVE CONNECTIONS; STRUCTURAL ASSOCIATIONS OF A PLURALITY OF MUTUALLY-INSULATED ELECTRICAL CONNECTING ELEMENTS; COUPLING DEVICES; CURRENT COLLECTORS
    • H01R13/00—Details of coupling devices of the kinds covered by groups H01R12/70 or H01R24/00 - H01R33/00
    • H01R13/02—Contact members
    • H01R13/22—Contacts for co-operating by abutting
    • H01R13/24—Contacts for co-operating by abutting resilient; resiliently-mounted
    • H01R13/2407—Contacts for co-operating by abutting resilient; resiliently-mounted characterized by the resilient means
    • H01R13/2421—Contacts for co-operating by abutting resilient; resiliently-mounted characterized by the resilient means using coil springs

Definitions

  • Hydrocarbons such as fossil fuels (e.g., oil) and natural gas
  • a perforating gun assembly or train or string of multiple perforating gun assemblies, are lowered into the wellbore, and positioned adjacent one or more hydrocarbon reservoirs in underground formations.
  • a typical perforating gun assembly may include explosive/perforating charges, typically shaped, hollow or projectile charges, that are ignited to create holes in the casing and to blast through the formation so that the hydrocarbons can flow through the casing and formation.
  • the perforating gun assembly may include one or multiple time delay subs positioned for the purpose of creating a time gap between events in the perforating gun assembly, e.g., between a percussion initiator being struck by a firing pin and the detonation of shaped charges.
  • Conventional perforating systems may provide for a pyrotechnic time delay device located within firing pin holders.
  • the pyrotechnic time delay device interposes a time delay between the initiation of the firing pin and the firing of the charges carried by the perforating gun assembly.
  • a time delay may be used, for example, to pressure balance the well for optimal perforation.
  • pyrotechnic material is selected and packaged such that ignition of the material will begin at one end and deflagration, i.e., burning, will proceed through the material at a certain velocity until it reaches the other end, where it ignites another element, e.g., a detonating cord or a bidirectional booster.
  • the time it takes deflagration to travel from one end to the other end determines the length of time delay. Since deflagration is a chemical reaction, it is highly dependent upon the physical environment in which it is occurring. One very important environmental factor is the temperature of the time delay device, which will typically be approximately equal to the temperature of the well bore. Since a deflagration rate will vary substantially with temperature, the time delay will also vary with temperature. Generally, operators using a pyrotechnical fuse must consult a time-temperature chart before estimating the actual time delay available based on the expected temperature downhole and exposure periods.
  • Pyrotechnic time delay devices typically have a maximum time delay, e.g., eight minutes. When this is the case, an operator must string multiple pyrotechnic time delay devices together in series to achieve longer delays. Due to the time and expense involved in perforating well bores and the explosive power of the devices used, it is essential that their operation be reliable and precise. Stringing together multiple pyrotechnic time delay devices diminishes the system’s reliability and increases the system cost and complexity.
  • Electronic time delay fuse assemblies provide increased system reliability and flexibility of operation of well perforating systems.
  • a time delay device that incorporates an electronics board with high precision timing circuitry and a power supply for the electronics produces a defined time-delay period between an explosive initiator and a separate electronic detonator.
  • An electrical contact between the electronics board and the electronic detonator such as a spring-loaded contact pin, may be used to transmit the output signal from the electronic circuitry to the electronic detonator.
  • commonly known spring-loaded contact pins may be structurally too weak to consistently withstand the shock impulses and blasts from neighboring gun assemblies, and may occasionally provide an intermittent contact to the detonator head that can disrupt the transmission of an electrical output signal from the electronic circuitry to the detonator.
  • spring-loaded contact pins typically joined by soldering to an electronics circuit board provide a very limited surface area for soldering contact, which increases the difficulty of assembling the time delay device and limits the flexibility of product designs.
  • the disclosure relates to a spring-loaded contact pin assembly for a circuit board.
  • the spring-loaded contact pin assembly may comprise a housing having a central bore formed axially in an interior of the housing.
  • a guide bushing may be positioned in the central bore.
  • the guide bushing may have an opening extending from a first open end to a second open end.
  • a spring may be positioned in the central bore and extend from the central bore into the second open end of the guide bushing.
  • a contact pin is provided having a first end extending from the first open end of the guide bushing and a second end in contact with the spring.
  • the contact pin may be retained in the housing by the guide bushing.
  • the contact pin is in electrical communication with the housing through the spring.
  • the housing may be mounted on and in electrical communication with a circuit board. This enables a signal to be transmitted from the circuit board to a detonator via the contact pin.
  • the disclosure relates to a circuit board assembly for a digital signal generating circuit of an electronic detonator.
  • the assembly comprises a circuit board, and a spring-loaded contact pin assembly as described above.
  • the first end of the contact pin is in electrical contact with a detonator such that an electronic signal from the circuit board is transferred through the contact pin to activate the detonator.
  • the disclosure relates to a method for providing a spring-loaded contact pin assembly for a circuit board.
  • the method may comprise providing a housing including a central bore formed axially in an interior of the housing, positioning a guide bushing in the central bore, the guide bushing having an opening extending from a first open end to a second open end, positioning a spring in the central bore, the spring extending from the central bore into the second open end of the guide bushing, and inserting a contact pin into the guide bushing such that a first end of the contact pin extends from the first open end of the guide bushing, a second end of the contact spring being in contact with the spring.
  • the contact pin is in electrical communication with the housing through the spring.
  • the contact pin may be retained in the housing by the guide bushing.
  • FIG. l is a cross-sectional view of a spring-loaded contact pin assembly and housing for use with an electrical time delay fuse, according to an aspect
  • FIG. 2 is a perspective view of a guide bushing of the spring-loaded circuit contact pin assembly of FIG. 1;
  • FIG. 3 is a perspective view of a contact pin of the spring-loaded circuit contact pin assembly of FIG. 1;
  • FIG. 4 is a view of a housing of the spring-loaded circuit contact pin assembly of FIG. 1;
  • FIG. 5 is a top view of the spring-loaded contact pin assembly of FIG. 1. in a fully assembled configuration
  • FIG. 6 is a bottom view of the spring-loaded contact pin assembly of FIG. 1 in a fully assembled configuration
  • FIG. 7 is a top perspective view of a guide bushing component of the spring-loaded contact pin assembly of FIG. 1;
  • FIG. 8 is a bottom perspective view of a guide bushing component of the spring- loaded contact pin assembly of FIG. 1;
  • FIG. 9 is a top elevated view of the spring-loaded contact pin assembly of FIG. 1 in a disassembled configuration.
  • FIG. 10 is a view of a time delay sub in accordance with an aspect.
  • FIG. 1 a cross-sectional view of a fully assembled contact pin assembly 100 for use with a time delay unit in a perforating gun assembly is illustrated.
  • a time delay unit is described in U.S. Patent Application No. 16/661,164, commonly owned and assigned to DynaEnergetics Europe GmbH.
  • the contact pin assembly 100 includes a housing 101.
  • the housing 101 may be coupled to an electronics board positioned in the perforating gun assembly (see Figure 10).
  • the housing 101 may be coupled to the electronics board by any known means that provides a resilient and secure connection.
  • the housing 101 is mounted by one or more screws (not shown) positioned in one or more screw holes 102 extending through the body of the housing 101.
  • more than one screw hole may extend through the body of the housing 101 for securing the housing to the electronics board, such as, for example, one screw hole 102 formed in each corner of the housing 101.
  • the screw hole(s) 102 may be threaded for threaded engagement of a threaded screw with an inner circumferential surface of the screw hole.
  • a central bore 103 is formed in and extends axially through an interior of the housing 101.
  • the central bore 103 in an exemplary embodiment is an opening formed in the housing 101 perpendicular to the screw hole 102 and defined by an inner circumferential surface/internal wall 104.
  • the inner circumferential surface 104 of the central bore 103 is threaded with internal threads 119 for threaded engagement with additional components of the contact pin assembly 100. Accordingly, it will be understood that, in an exemplary embodiment, the housing 101 may be mounted without requiring the use of soldering.
  • a guide bushing 105 is positioned in the central bore 103 of the housing 101 of the contact pin assembly 100.
  • the guide bushing 105 includes a first open end 106, a second open end 107, and an opening 108 extending between the first open end 106 and the second open end 107.
  • the first open end 106 includes a non-threaded exterior surface defining a first diameter Dl
  • the second open end 107 includes a threaded exterior surface (external threads) 118 defining a second diameter D2 which correspond to the internal threads 119 of the central bore 103.
  • the first diameter Dl of the first open end/non-threaded end 106 is greater than the second diameter D2 of the second open end/threaded end 107.
  • the second diameter D2 of the second open end 107 corresponds to a diameter of the central bore 103, as defined by the interior wall 104.
  • the second open end 107 is positioned in the central bore 103 such that the threaded exterior surface 118 of the second open end 107 contacts and engages the threaded surface 119 of the central bore for securing the guide bushing 105 in the central bore 103 of the housing 101.
  • the axial opening 108 extending along the length of the bushing 105 has a first inner diameter segment 109 adjacent the first open end 106, and a second inner diameter segment 110 adjacent the second open end 107.
  • the first inner diameter segment 109 has a first inner diameter IDl that is smaller than a second inner diameter ID2 of the second inner diameter segment 110.
  • a tapered wall 111 extends in an interior of the guide bushing 105 between the second inner diameter segment 110 and the first inner diameter segment 109 of the axial opening 108.
  • the tapered wall 111 extends radially inward toward the axial opening 108, such that it is a transition between the first inner diameter segment 109 and a second inner diameter segment 110.
  • the tapered wall 111 is spaced apart from both the first open end 106 and the second open end 107 of the guide bushing 105.
  • An exemplary embodiment of the guide bushing 105 is shown in FIGS. 7 and 8.
  • a contact pin 112 having an outer diameter OD1 equal to the first inner diameter IDl of the inner diameter segment 109 of the guide bushing 105 may be inserted through the axial opening 108. This may be done before the guide bushing 105 is secured in the central bore 103.
  • the contact pin 112 passes through the axial opening 108 in the guide busing 105, with the first end 115 protruding through the non-threaded end/first open end 106 of the guide bushing 105.
  • An exemplary embodiment of the contact assembly 100 in a fully assembled configuration is shown in FIGS. 5 and 6.
  • the contact pin 112 is retained in the housing 101 by the guide bushing 105.
  • the contact pin 112 may include a shoulder 113 that protrudes radially around an external body portion of the contact pin 112.
  • the shoulder 113 has an outer diameter OD2 that is greater than the outer diameter OD1 of the contact pin 112, but less than or equal to the second diameter D2 of the second open end 107 and the inner diameter ID2 of the second diameter segment 110 of the guide bushing 105.
  • the shoulder 113 is positioned in the second diameter segment 110 of the guide bushing 105 and contacts the tapered wall 111 in the axial opening 108.
  • a spring 114 is positioned in the central bore 103 and extends from an inner wall of the central bore 103 of the housing 101 into the second open end 107 of the guide bushing 103.
  • the spring 114 surrounds the second end 116 of the contact pin 112 and abuts against the shoulder 113 of the contact pin 112 to frictionally or compressively bias the contact pin 112 against the tapered wall 111 of the guide bushing 105.
  • the contact pin 112 has a first end 115 that protrudes from the first open end 106 of the guide bushing 105 and a second end 116 housed in the central bore 103 of the housing 101 in contact with the spring 114.
  • the diameter of the spring 114 is less than the diameter of each of the central bore 103 of the housing 101 and the second diameter segment 110 of the guide bushing 105 such that the spring 114 may be positioned in the second diameter segment 110 that in turn is positioned inside the central bore 103 of the housing.
  • the contact pin 112 is in electrical communication with the housing 101 through the spring 114.
  • the components of the contact pin assembly 100 are formed from conductive materials such that when the components are assembled an electrical connection is made between and through the contact assembly 100. This enables a signal to be transmitted from a circuit board to a detonator via the contact pin 112.
  • the assembly components can be made from any conductive material and may be made from different conductive materials in a single contact assembly.
  • the contact assembly components may be made of steel or aluminum.
  • the contact assembly 100 may be installed or mounted on the bottom side of the electronic circuit board, and is adaptable to different applications by changing the dimensions and/or orientation of the contact pin 112 relative to the housing 101. Further, installation by screwing the contact assembly 100 to the electronics circuit board creates a more stable connection for consistent electrical connectivity between the electronics circuit board, the contact pin assembly, and the detonator of the perforating gun system.
  • Figure 10 shows a time delay sub with circuit board assembly 120 for a digital signal generating circuit, such as a time-delay circuit, of an electronic detonator 122.
  • the circuit board assembly 120 comprises a circuit board 121 comprising time-delay circuitry and the spring- loaded contact pin assembly 100 (as discussed above) which is fixed to the circuit board 121.
  • the first end 115 of the contact pin is in electrical contact with a detonator 122 such that an electronic signal from the circuit board 121 is transferred through the contact pin 112 to activate the detonator 122.
  • Embodiments of the disclosure are further associated with a method of providing and installing a spring-loaded contact pin assembly 100 for an electronics circuit board 121.
  • a housing 101 is provided which includes a central bore 103 formed axially in an interior of the housing 101.
  • a guide bushing 105 is positioned in the central bore 103, the guide bushing 105 having an opening 108 extending from a first open end 106 to a second open end 107.
  • a spring 114 is positioned in the central bore 103, the spring 114 extending from the central bore 103 into the second open end 107 of the guide bushing 105.
  • a contact pin 112 is then inserted into the guide bushing 105 such that a first end 115 of the contact pin 112 extends from the first open end 106 of the guide bushing 105, with a second end 116 of the contact spring 112 being in contact with the spring 114.
  • the contact pin 112 is retained in the housing 101 by the guide bushing 105 and is in electrical communication with the housing 101 through the spring 114.
  • the method may also include features and functionality of spring-loaded contact pin assembly 100 and circuit board assembly 120 discussed above in connection with Figures 1-10.
  • the contact pin 112 may be positioned in an axial opening of a guide bushing 105 such that a first end 115 of the contact pin 112 protrudes through the first open end 106 of the guide bushing 105.
  • An internal tapered wall 111 of the guide bushing 105 contacts a shoulder 113 formed radially on the contact pin 112 to prevent passage of the contact pin 112 entirely through the axial opening 108 of the guide bushing 105.
  • the spring 114 may be positioned in a second diameter segment 110 of the guide bushing 105.
  • the guide bushing 105 may be inserted into and secured via threaded engagement with an interior threaded surface 119 of a central bore 103 formed in the housing 101. Securement of the guide bushing 105 in the central bore 103 compresses the spring 114 to bias the contact pin 112 against the tapered wall 111 and to establish an electrical connection between each of the guide bushing 105, the contact pin 112, the spring 114, and the housing 101. Screws are inserted into screw holes 102 formed through the housing 101 to mount to the housing 101 to the electronics circuit board. An electrical connection between the contact pin assembly 100, the electronics circuit board 121, and a detonator 122 is established.
  • This disclosure in various embodiments, configurations and aspects, includes components, methods, processes, systems, and/or apparatuses as depicted and described herein, including various embodiments, sub-combinations, and subsets thereof.
  • This disclosure contemplates, in various embodiments, configurations and aspects, the actual or optional use or inclusion of, e.g., components or processes as may be well-known or understood in the art and consistent with this disclosure though not depicted and/or described herein.
  • each of the expressions “at least one of A, B and C”, “at least one of A, B, or C”, “one or more of A, B, and C", “one or more of A, B, or C" and "A, B, and/or C” means A alone, B alone, C alone, A and B together, A and C together, B and C together, or A, B and C together.
  • Approximating language may be applied to modify any quantitative representation that could permissibly vary without resulting in a change in the basic function to which it is related. Accordingly, a value modified by a term such as “about” is not to be limited to the precise value specified. In some instances, the approximating language may correspond to the precision of an instrument for measuring the value. Terms such as “first,” “second,” “upper,” “lower” etc. are used to identify one element from another, and unless otherwise specified are not meant to refer to a particular order or number of elements.
  • the terms “may” and “may be” indicate a possibility of an occurrence within a set of circumstances; a possession of a specified property, characteristic or function; and/or qualify another verb by expressing one or more of an ability, capability, or possibility associated with the qualified verb. Accordingly, usage of "may” and “may be” indicates that a modified term is apparently appropriate, capable, or suitable for an indicated capacity, function, or usage, while taking into account that in some circumstances the modified term may sometimes not be appropriate, capable, or suitable. For example, in some circumstances an event or capacity can be expected, while in other circumstances the event or capacity cannot occur - this distinction is captured by the terms “may” and “may be.”

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  • Life Sciences & Earth Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Geology (AREA)
  • Mining & Mineral Resources (AREA)
  • Physics & Mathematics (AREA)
  • Environmental & Geological Engineering (AREA)
  • Fluid Mechanics (AREA)
  • General Life Sciences & Earth Sciences (AREA)
  • Geochemistry & Mineralogy (AREA)
  • Measuring Leads Or Probes (AREA)

Abstract

Un ensemble broche de contact à ressort est décrit. L'ensemble broche de contact peut comprendre un boîtier comprenant un alésage central formé axialement à l'intérieur du boîtier. Une bague de guidage ayant une ouverture s'étendant entre une première extrémité ouverte et une seconde extrémité ouverte peut être positionnée dans l'alésage central. Un ressort peut être positionné dans l'alésage central et s'étendre dans la seconde extrémité ouverte de la bague de guidage. Une broche de contact est dotée d'une première extrémité s'étendant depuis la première extrémité ouverte de la bague de guidage et d'une seconde extrémité en contact avec le ressort. La broche de contact peut être retenue dans le boîtier par la bague de guidage et est en communication électrique avec le boîtier par l'intermédiaire du ressort. Un ensemble carte de circuit imprimé pour un circuit de génération de signal numérique comprenant un tel ensemble broche de contact, et un procédé de fourniture d'un tel ensemble broche de contact sont également prévus.
PCT/EP2021/062985 2020-05-18 2021-05-17 Ensemble broche de contact à ressort, ensemble carte de circuit imprimé comprenant un circuit de temporisation, et procédés correspondants WO2021233823A1 (fr)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
US202063026511P 2020-05-18 2020-05-18
US63/026,511 2020-05-18

Publications (1)

Publication Number Publication Date
WO2021233823A1 true WO2021233823A1 (fr) 2021-11-25

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ID=76392322

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/EP2021/062985 WO2021233823A1 (fr) 2020-05-18 2021-05-17 Ensemble broche de contact à ressort, ensemble carte de circuit imprimé comprenant un circuit de temporisation, et procédés correspondants

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WO (1) WO2021233823A1 (fr)

Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4306628A (en) * 1980-02-19 1981-12-22 Otis Engineering Corporation Safety switch for well tools
WO2018057934A1 (fr) * 2016-09-23 2018-03-29 Hunting Titan, Inc. Système de cartouche de perforation à pression d'incendie sélectionnée

Patent Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4306628A (en) * 1980-02-19 1981-12-22 Otis Engineering Corporation Safety switch for well tools
WO2018057934A1 (fr) * 2016-09-23 2018-03-29 Hunting Titan, Inc. Système de cartouche de perforation à pression d'incendie sélectionnée

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