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US3794953A - Electrical terminal for conductive foil - Google Patents

Electrical terminal for conductive foil Download PDF

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Publication number
US3794953A
US3794953A US3794953DA US3794953A US 3794953 A US3794953 A US 3794953A US 3794953D A US3794953D A US 3794953DA US 3794953 A US3794953 A US 3794953A
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Prior art keywords
member
conductive
terminal
electrical
block
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Legal status (The legal status 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 status listed.)
Expired - Lifetime
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J Malin
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Security Instr Inc
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    • HELECTRICITY
    • H01BASIC ELECTRIC ELEMENTS
    • H01RLINE CONNECTORS; CURRENT COLLECTORS
    • H01R12/00Structural associations of a plurality of mutually-insulated electrical connecting elements, specially adapted for printed circuits, e.g. printed circuit boards [PCBs], 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
    • H01R12/50Fixed connections
    • H01R12/51Fixed connections for rigid printed circuits or like structures
    • H01R12/55Fixed connections for rigid printed circuits or like structures characterised by the terminals
    • H01R12/57Fixed connections for rigid printed circuits or like structures characterised by the terminals surface mounting terminals
    • HELECTRICITY
    • H01BASIC ELECTRIC ELEMENTS
    • H01RLINE CONNECTORS; CURRENT COLLECTORS
    • H01R11/00Connectors providing two or more spaced connecting locations for conductive members which are thereby interconnected; End pieces for wires or cables, supported by the wire or cable and for facilitating electrical connection to some other wire, terminal, or conductive member
    • H01R11/11End pieces or tapping pieces for wires, supported by the wire and for facilitating electrical connection to some other wire, terminal or conductive member
    • H01R11/22End pieces terminating in a spring clip
    • YGENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10STECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10S439/00Electrical connectors
    • Y10S439/917Alarm circuit, e.g. window affixed foil

Abstract

An electrical terminal is disclosed that is adapted to be adhesively retained upon a smooth surface such as glass. The terminal contains a flat generally U shaped spring member encircling a cooperating insulator block member. The spring member completes an electrical path to a frangible conductive tape carried by the glass from an electrically conductive wire held in intimate contact with the spring member by screws. The aforementioned Abstract is neither intended to define the invention of the application which, of course, is measured by the claims, not is it intended to be limiting as to the scope of the invention in any way.

Description

United States Patent 1 [111 3,794,953

Malin Feb. 26, 1974 ELECTRICAL TERMINAL FOR CONDUCTIVE FOIL Jack Malin, Beechhurst, N.Y.

Security Instruments, Inc., Bronx, NY.

Filed: Jan. 22, 1973 Appl. No.: 325,562

Inventor:

Assignee:

US. Cl 339/17 C, 174/68.5, 174/117 A, 339/125 R, 339/269 Int. Cl I-I0lr 9/10 Field of Search 339/17, 75, 119, 125, 269, 339/271; 174/68.5, 117 A [56] References Cited UNITED STATES PATENTS 3,444,502 5/1969 Matthews 339/17 C 3,611,249 10/1971 Lovrenich 339/271 FOREIGN PATENTS OR APPLICATIONS 756,758 4/1967 Canada 339/119 R Primary Examiner-Joseph H. McGlynn Attorney, Agent, or Firm--Leonard H. King The aforementioned Abstract is neither intended to define the invention of the application which, of course, is measured by the claims, notis it intended to be limiting as to the scope of the invention in any way.

7 Claims, 3 Drawing Figures H (e W Y Z A ELECTRICAL TERMINAL FOR CONDUCTIVE FOIL BACKGROUND OF THE INVENTION This invention relates to electrical terminals and, in particular, to an electrical terminal adapted to be affixed to a smooth surface such as glass, which provides a complete conductive path from a wire retained on the terminal block member to an electrically conductive frangible tape provided on the smooth surface.

Present day burglar alarm systems are designed to detect essentially all means of entry to a secured premises. Since glass windows and doors are particularly vulnerable to destruction by a person seeking unlawful entry to the premises, these entrances are generally provided with a means for detecting breaking of the glass. The alarm system normally includes an electrical circuit which will activate the alarm if electrical conductivity is interrupted. Conventionally, the glass to be protected is coated with an adhesive backed frangible electrically conductive metallic tape about the circumference of the glass, generally a few inches from the edges thereof. Breaking or cutting the glass causes it to shatter and tear the conductive tape thereby breaking the circuit. The path is generally a series path between all conductive tapes and wires and completes an electrically conductive path to a relay. A break at any point in the series conductive path deenergizes the relay and activates the alarm.

The prior art method of connection to the tape was to solder a conductive wire to the conductive tape after the tape has been affixed to the glass. The wire was then connected to a fixed terminal mounted on the window frame which had another wire affixed thereon connected to the electrical circuitry. Extreme care was required when soldering the wire to the metallic tape in order that the tape not be torn or the window broken. It will be appreciated that this made the installation time consuming, hence costly as well as precarious.

SUMMARY OF THE INVENTION The preferred embodiment of the present invention provides a terminal that may be affixed to a smooth surface such as glass and provides intimate electrical contact with a metallic conductive tape provided thereon, thus, eliminating the need for soldering to the tape or mounting a terminal on a surrounding molding or wall.

An electrical terminal fabricated in accordance with the principles of the present invention comprises in combination, an insulated block member having a top and bottom surface, the top surface having a hole provided therein, an electrically conductive spring member having a hole therein adapted to cooperate with the hole in the insulated block, the spring member encircling the block member and normally extending beyond the bottom surface thereof. The terminal further includes, adhesive means, provided on the bottom surface of the block member, for retaining the block member on a surface and adapted to retain the spring member in intimate contact with an electrical conductor provided on the surface of the glass, and screw means adapted to cooperate with the holes and adapted to complete an electrically conductive path between the wire affixed thereunder and the electrical surface conductor.

These and other objects and advantages of the invention will appear more clearly from the following specification in connection with the accompanying drawing.

DESCRIPTION OF THE DRAWING FIG. 1 is a pictorial representation of a burglar alarm system including an enlarged perspective view of an adhesively secured terminal fabricated in accordance with the principles of the present invention;

FIG. 2 is an enlarged cross-sectional view in elevation of the adhesive spring terminal of FIG. 1 taken along line 22 thereof; and

FIG. 3 is an enlarged cross-sectional view, in elevation, of the adhesive spring terminal of FIG. 1 taken along line 3-3 thereof.

DESCRIPTION OF THE PREFERRED EMBODIMENT Referring now to the drawing, (FIGS. 1, 2 and 3) wherein the numeral 10 generally refers to a burglar alarm system. The burglar alarm system in the preferred embodiment includes a housing 12, within which is incorporated all of the conventional alarm electrical circuit components including a relay, not shown, a siren or bell 11 is connected to the relay. A conventional line cord 14 and a plug 16 which is adapted to be plugged into a source of electrical power, not shown, is coupled to the housing 12 and supplies the electrical energy for the alarm system. Alternatively a battery, not shown, mounted within the housing 12 supplies the energy for the electrical circuitry, should the AC power fail or be disconnected for any reason. Other systems may be solely AC or battery operated. A pair of terminals 18 and 20 are provided on the housing 12 which are coupled to the electrical circuitry within the housing. The electrical circuitry is designed not to activate the alarm system as long as an electrically conductive path is maintained between the terminals l8 and 20.

The burglar alarm system 10 is designed to activate the alarm device such as a siren or hell 1 1, when a protected glass window is broken. An electrically conductive tape 22, which is provided with an adhesive backing 24 is affixed to a glass window 26. The tape is generally affixed about the windows periphery a few inches from each edge. An electrical terminal 28 is adhesively affixed to the glass window 26 straddling the conductive tape as shown in FIG. 1 by an adhesive material 31 carried by a foam pad 30 provided along bottom edge 32 and 34 on either side of a bottom channel 36 of an insulating block member 38. The preferred adhesive material includes a polyurethane foam pad 30 and a pressure sensitive adhesive layer 31 protected by a non-adherent strippable film 33.

Block member 38, in the preferred embodiment, is molded in a unitary structure of an electrically nonconductive thermoplastic material, such as polystyrene, and has sloped or chamfered sides 40 terminating in a flat top surface 42. The top surface 42 is provided with a hole 44 therein. Hole 44 may be threaded to cooperate with a screw 46 or, for added strength, provided with a metal bushing 48 which has threads therein. The bushing member 48 may be insert molded or inserted after block member 38 is molded.

A metal flat or leaf spring member 50 is formed to have a generally U shape and is provided with a hole 52 which is adapted to cooperate with the hole 44 provided in the top surface 42 of block member 38. Spring member 50 is fabricated of an electrically conductive metallic material and encircles block member 38 by extending downwardly within a rear channel 54 (FIG. 2) provided in block member 38 and forwardly within the bottom channel 36 of block 38. Spring 50in its relaxed or uncompressed state extends below the bottom surface of edges 32 and 34. When the adhesive terminal block 28 is affixed to the glass surface the spring 50 is compressed thereby insuring intimate contact with the conducting tape 22.

In operation, an electrically conductive wire 56 is connected from terminal 18 of the housing 12 to the screw 46 of terminal 28. Tightening screw 46 with the wire 56 thereunder, completes the electrical path from terminal 18 to the conductive tape 22. A second terminal, not shown, is applied in the same manner as terminal 28 to the glass at the other end of the conductive tape 22. A second electrically conductive wire 58 is connected from terminal 20 to the other terminal thereby forming a complete electrically conductive path between the terminals 18 and 20. If the glass is broken for any reason the conductive tape 22 would be torn or the adhesive terminal 38 would be removed from the glass, thus, the continuous conductive path between terminals 18 and 20 would be broken'and the alarm would be activated.

Note that, although a single glass window utilizing two adhesive terminals has been described by way of example, any number of windows may be protected by using additional terminals and being certain that a continuous series electrically conductive path is maintained between terminals 18 and 20. A break at any point within the path will activate the alarm.

Hereinbefore there has been disclosed an electrical spring terminal which is relatively inexpensive to manufacture, easy to install and ideally suited for mounting on smooth surfaces such as glass.

There has been disclosed heretofore the best embodiment of the invention presently contemplated. However, it is to be understood that various changes and modifications may be made by those skilled in the art without departing from the spirit of the invention.

What I claim as new and desire to secure by Letters Patent is:

1. An electrical terminal for being adhesively secured to a surface carrying a frangible conductive strip comprising in combination:

a. an electrically non-conductive block member having a top and bottom surface, said top surface having a threaded bore extending therefrom;

b. an electrically conductive spring member having a hole therein aligned with the bore in said insulated block member,'said spring member encircling said block member and normally extending beyond said bottom surface thereof;

0. adhesive means provided on said bottom surface of said block member for retaining said block member on a surface whereby the said spring member is depressed to a compressed condition and is adapted to retain said spring member in intimate contact with the electrical conductor provided on said surface; and

d. screw means adapted to cooperate with said holes and adapted to complete an electrically conductive path between a wire affixed thereunder and the frangible conductive strip.

2. An electrical terminal according to claim 1 wherein said spring member is fabricated of electrically conductive flat spring material being generally of a U shape.

3. An electrical terminal according to claim 1 wherein said block member is fabricated of a unitary thermoplastic electrically non-conductive material.

4. An electrical terminal according to claim 1 further including a threaded metal insert provided within said insulated block member and adapted to retain said screw means.

5. An electrical terminal according to claim 1 including a foam pad interposed between the said adhesive means and said block member.

6. The electrical terminal of claim 5 wherein said adhesive means is pressure sensitive.

7. The electrical terminal of claim 5 wherein said adhesive means if provided with a strippable protective layer.

Claims (7)

1. An electrical terminal for being adhesively secured to a surface carrying a frangible conductive strip comprising in combination: a. an electrically non-conductive block member having a top and bottom surface, said top surface having a threaded bore extending therefrom; b. an electrically conductive spring member having a hole therein aligned with the bore in said insulated block member, said spring member encircling said block member and normally extending beyond said bottom surface thereof; c. adhesive means provided on said bottom surface of said block member for retaining said block member on a surface whereby the said spring member is depressed to a compressed condition and is adapted to retain said spring member in intimate contact with the electrical conductor provided on said surface; and d. screw means adapted to cooperate with said holes and adapted to complete an electrically conductive path between a wire affixed thereunder and the frangible conductive strip.
2. An electrical terminal according to claim 1 wherein said spring member is fabricated of electrically conductive flat spring material being generally of a U shape.
3. An electrical terminal according to claim 1 wherein said block member is fabricated of a unitary thermoplastic electrically non-conductive material.
4. An electrical terminal according to claim 1 further including a threaded metal insert provided within said insulated block member and adapted to retain said screw means.
5. An electrical terminal according to claim 1 including a foam pad interposed between the said adhesive means and said block member.
6. The electrical terminal of claim 5 wherein said adhesive means is pressure sensitive.
7. The electrical terminal of claim 5 wherein said adhesive means if provided with a strippable protective layer.
US3794953A 1973-01-22 1973-01-22 Electrical terminal for conductive foil Expired - Lifetime US3794953A (en)

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Cited By (16)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4355199A (en) * 1975-10-10 1982-10-19 Luc Penelope Jane Vesey Conductive connections
FR2522890A1 (en) * 1982-03-05 1983-09-09 Telemecanique Electrique card connection terminal PRINTED CIRCUIT and apparatus using such terminals
US4555158A (en) * 1984-08-06 1985-11-26 The Wallace Companies, Inc. Modular connector and system containing the same
US4688875A (en) * 1986-09-15 1987-08-25 American Telephone And Telegraph Company Spring contact structure
US4734043A (en) * 1986-02-11 1988-03-29 E. I. Du Pont De Nemours And Company Modular jack
US4997396A (en) * 1990-01-22 1991-03-05 Peter Gold Weatherproof vehicle rear window defroster electrical connection
US5265329A (en) * 1991-06-12 1993-11-30 Amp Incorporated Fiber-filled elastomeric connector attachment method and product
EP0671782A1 (en) * 1994-01-13 1995-09-13 Rkc Instrument Inc. Electric terminal assembly
US6292087B1 (en) 1998-07-31 2001-09-18 Flexcon Company, Inc. Fuse indicator label
WO2004012302A1 (en) * 2002-07-26 2004-02-05 Antaya Technologies Corporation Non-solder adhesive terminal
US6705876B2 (en) * 1998-07-13 2004-03-16 Formfactor, Inc. Electrical interconnect assemblies and methods
US20080305652A1 (en) * 2007-06-07 2008-12-11 Boeing Company Method and apparatus and method for connecting a first flat conductor with a second conductor
US20090253305A1 (en) * 2008-04-02 2009-10-08 International Business Machines Corporation Replacement clip and method for repairing a modular cable connector having a broken locking clip
WO2011134714A1 (en) * 2010-04-30 2011-11-03 Few Fahrzeugelektrikwerk Gmbh & Co. Kg Contacting assembly for conductors present on flat structures, in particular glass panels
WO2012065893A1 (en) * 2010-11-17 2012-05-24 Few Fahrzeugelektrikwerk Gmbh & Co. Kg Contact-making arrangement for conductors provided on flat structures, namely panes of glass
US20140154914A1 (en) * 2010-02-03 2014-06-05 Te Connectivity Nederland B.V. Enclosure assembly for a connector, strain relief element, and method

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CA756758A (en) * 1967-04-11 Eisert Josef Terminal assembly
US3444502A (en) * 1966-01-26 1969-05-13 Lucas Industries Ltd Means for making an electrical connection between an electrical component and a printed circuit
US3611249A (en) * 1968-10-16 1971-10-05 Magnum Electric Corp Completely mechanical solderless electrical terminal assembly for connecting a wire to a circuit board

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CA756758A (en) * 1967-04-11 Eisert Josef Terminal assembly
US3444502A (en) * 1966-01-26 1969-05-13 Lucas Industries Ltd Means for making an electrical connection between an electrical component and a printed circuit
US3611249A (en) * 1968-10-16 1971-10-05 Magnum Electric Corp Completely mechanical solderless electrical terminal assembly for connecting a wire to a circuit board

Cited By (39)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4355199A (en) * 1975-10-10 1982-10-19 Luc Penelope Jane Vesey Conductive connections
US4480779A (en) * 1975-10-10 1984-11-06 Luc Technologies Limited Conductive connections
FR2522890A1 (en) * 1982-03-05 1983-09-09 Telemecanique Electrique card connection terminal PRINTED CIRCUIT and apparatus using such terminals
EP0088676A1 (en) * 1982-03-05 1983-09-14 Telemecanique Electric terminal post for printed circuits and device making use of said terminal posts
US4555158A (en) * 1984-08-06 1985-11-26 The Wallace Companies, Inc. Modular connector and system containing the same
WO1986001341A1 (en) * 1984-08-06 1986-02-27 Hui Ping Lam Modular connector and system containing the same
EP0192642A1 (en) * 1984-08-06 1986-09-03 Hui Ping Lam Modular connector and system containing the same.
EP0192642A4 (en) * 1984-08-06 1986-12-03 Hui Ping Lam Modular connector and system containing the same.
US4734043A (en) * 1986-02-11 1988-03-29 E. I. Du Pont De Nemours And Company Modular jack
US4688875A (en) * 1986-09-15 1987-08-25 American Telephone And Telegraph Company Spring contact structure
US4997396A (en) * 1990-01-22 1991-03-05 Peter Gold Weatherproof vehicle rear window defroster electrical connection
US5265329A (en) * 1991-06-12 1993-11-30 Amp Incorporated Fiber-filled elastomeric connector attachment method and product
EP0671782A1 (en) * 1994-01-13 1995-09-13 Rkc Instrument Inc. Electric terminal assembly
US7169646B2 (en) 1998-07-13 2007-01-30 Formfactor, Inc. Interconnect assemblies and methods
US20060024988A1 (en) * 1998-07-13 2006-02-02 Formfactor, Inc. Interconnect assemblies and methods
US6948941B2 (en) 1998-07-13 2005-09-27 Formfactor, Inc. Interconnect assemblies and methods
US6705876B2 (en) * 1998-07-13 2004-03-16 Formfactor, Inc. Electrical interconnect assemblies and methods
US20040127074A1 (en) * 1998-07-13 2004-07-01 Formfactor, Inc. Interconnect assemblies and methods
US7618281B2 (en) 1998-07-13 2009-11-17 Formfactor, Inc. Interconnect assemblies and methods
US20070123082A1 (en) * 1998-07-13 2007-05-31 Formfactor, Inc. Interconnect Assemblies And Methods
US6459357B2 (en) 1998-07-31 2002-10-01 Flexcon Company, Inc. Fuse indicator label
US6292087B1 (en) 1998-07-31 2001-09-18 Flexcon Company, Inc. Fuse indicator label
US6809627B2 (en) 1998-07-31 2004-10-26 FLEXcon, Inc. Fuse indicator label
WO2004012302A1 (en) * 2002-07-26 2004-02-05 Antaya Technologies Corporation Non-solder adhesive terminal
US6840780B1 (en) 2002-07-26 2005-01-11 Antaya Technologies Corporation Non-solder adhesive terminal
US7507100B2 (en) * 2007-06-07 2009-03-24 Boeing Company Method and apparatus and method for connecting a first flat conductor with a second conductor
US20080305652A1 (en) * 2007-06-07 2008-12-11 Boeing Company Method and apparatus and method for connecting a first flat conductor with a second conductor
US20090253305A1 (en) * 2008-04-02 2009-10-08 International Business Machines Corporation Replacement clip and method for repairing a modular cable connector having a broken locking clip
US7708581B2 (en) * 2008-04-02 2010-05-04 International Business Machines Corporation Replacement clip and method for repairing a modular cable connector having a broken locking clip
US20140154914A1 (en) * 2010-02-03 2014-06-05 Te Connectivity Nederland B.V. Enclosure assembly for a connector, strain relief element, and method
US9379488B2 (en) * 2010-02-03 2016-06-28 Te Connectivity Nederland B.V. Enclosure assembly for a connector, strain relief element, and method
CN102948252A (en) * 2010-04-30 2013-02-27 Few汽车电器厂有限责任两合公司 Contacting assembly for conductors present on flat structures, in particular glass panels
WO2011134714A1 (en) * 2010-04-30 2011-11-03 Few Fahrzeugelektrikwerk Gmbh & Co. Kg Contacting assembly for conductors present on flat structures, in particular glass panels
US8905778B2 (en) 2010-04-30 2014-12-09 Few Fahrzeugelektrikwerk Gmbh & Co. Kg Contacting assembly for conductors present on flat structures, in particular glass panels
CN102948252B (en) * 2010-04-30 2015-05-06 Few汽车电器厂有限责任两合公司 Contacting assembly for conductors present on flat structures
WO2012065893A1 (en) * 2010-11-17 2012-05-24 Few Fahrzeugelektrikwerk Gmbh & Co. Kg Contact-making arrangement for conductors provided on flat structures, namely panes of glass
US8932074B2 (en) 2010-11-17 2015-01-13 Few Fahrzeugelektrikwerk Gmbh & Co. Kg Contact making arrangement for conductors provided on flat structures, namely panes of glass
CN103229591B (en) * 2010-11-17 2015-11-25 Few汽车电器厂有限责任两合公司 Structure for plane, i.e., the conductor contacts on the glass structural unit is turned on
CN103229591A (en) * 2010-11-17 2013-07-31 Few汽车电器厂有限责任两合公司 Contact-making arrangement for conductors provided on flat structures, namely panes of glass

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