US3646490A - Mercury switch - Google Patents

Mercury switch Download PDF

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Publication number
US3646490A
US3646490A US66534A US3646490DA US3646490A US 3646490 A US3646490 A US 3646490A US 66534 A US66534 A US 66534A US 3646490D A US3646490D A US 3646490DA US 3646490 A US3646490 A US 3646490A
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US
United States
Prior art keywords
mercury
envelope
armature
wettable
enclosure
Prior art date
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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US66534A
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English (en)
Inventor
Sheldon S Bitko
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
PNC Bank NA
Original Assignee
Fifth Dimension Inc
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Filing date
Publication date
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Publication of US3646490A publication Critical patent/US3646490A/en
Anticipated expiration legal-status Critical
Assigned to PNC BANK, NATIONAL ASSOCIATION reassignment PNC BANK, NATIONAL ASSOCIATION SECURITY INTEREST (SEE DOCUMENT FOR DETAILS). Assignors: FIFTH DIMENSION, INC.
Assigned to PNC BANK, N.A. reassignment PNC BANK, N.A. ASSIGNMENT OF ASSIGNORS INTEREST (SEE DOCUMENT FOR DETAILS). Assignors: FIFTH DIMENSION, INC.
Expired - Lifetime legal-status Critical Current

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Classifications

    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01H—ELECTRIC SWITCHES; RELAYS; SELECTORS; EMERGENCY PROTECTIVE DEVICES
    • H01H51/00—Electromagnetic relays
    • H01H51/28—Relays having both armature and contacts within a sealed casing outside which the operating coil is located, e.g. contact carried by a magnetic leaf spring or reed
    • H01H51/284—Polarised relays
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01H—ELECTRIC SWITCHES; RELAYS; SELECTORS; EMERGENCY PROTECTIVE DEVICES
    • H01H1/00—Contacts
    • H01H1/06—Contacts characterised by the shape or structure of the contact-making surface, e.g. grooved
    • H01H1/08—Contacts characterised by the shape or structure of the contact-making surface, e.g. grooved wetted with mercury
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01H—ELECTRIC SWITCHES; RELAYS; SELECTORS; EMERGENCY PROTECTIVE DEVICES
    • H01H36/00—Switches actuated by change of magnetic field or of electric field, e.g. by change of relative position of magnet and switch, by shielding
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01H—ELECTRIC SWITCHES; RELAYS; SELECTORS; EMERGENCY PROTECTIVE DEVICES
    • H01H51/00—Electromagnetic relays
    • H01H51/28—Relays having both armature and contacts within a sealed casing outside which the operating coil is located, e.g. contact carried by a magnetic leaf spring or reed
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01H—ELECTRIC SWITCHES; RELAYS; SELECTORS; EMERGENCY PROTECTIVE DEVICES
    • H01H51/00—Electromagnetic relays
    • H01H51/28—Relays having both armature and contacts within a sealed casing outside which the operating coil is located, e.g. contact carried by a magnetic leaf spring or reed
    • H01H51/284—Polarised relays
    • H01H51/285—Polarised relays for latching of contacts

Definitions

  • the interior of the enclosure and the diaphragm may be mercury wettable, excluding only an insulating feedthrough button for a stationary contact, and also excluding a portion of the face of the contact which is intended to sustain impact by the armature, the mercury wettable portion of that face being indented with respect to the impact area, and the quantity of mercury in the enclosure being sufficient, but only sufficient, to sustain a thin layer of mercury on the mercury wettable surfaces.
  • the enclosure may be nonmetallic, e.g., ceramic, provided with mercury wettable screen surfaces.
  • Thepresent invention employsa nonmagnetic'metallic envelope, a stationary contact or contacts, anchored via a nonwettable insulator or insulators in a wall or walls of the envelope, andanarmature in the form'of a single spiral, suchas is used as amainspring in a watch.
  • the turns of the spiral have spacings adapted to hold mercury, and the entire helix is mercury wettable, and'all the turns of'the spiral, of which there are many, interact with each other and with themercury.
  • the header could be magnetic and the cap nonmagnetic, or vice versa,or both' headerand cap could be magnetic if nonmagnetic windows are provided in the magnetic element to permit entrance of-magnetic'flux.
  • the spiral provides a very considerable'high' surface tension reservoir of mercury as a'continuo'us thinlayeron itssurface, and the layer readily reintegrates itself whenbrokenby operationof the relay.
  • the spring can-besmall'or large, and-there is no longer a requirement that the switch'be small, as in theDonath device. It can be'madetohandle 50 aof current if desired.
  • the interior walls ofthe enclosure which is in the form ofa header and cap welded togeth'enaremercury wettable, except for theinsulatorswhich enable stationary contacts to feed through.
  • the spiral is physically-securedat its perimeter to the envelope, either byweldingor-clamping or it maybe loosely laid on a circumferential securing'slot, and the envelope'can then constitute a switch output electrode, the spiral operating as a damped'reed.
  • Damping factors can be designed for reed vibration frequency.
  • the very long reed spring can be made extremely flexible, so that in operation it can impact against the envelope but its impact against the envelope has no effect on switching and does result in'redistributing mercury. In the present device the spring permits a major reservoir of mercury, and the-structure lends itselfto fabrication in relatively large diameter, thin envelopes, which are inexpensive to make.
  • Diaphragm-type switches which do not employ mercury are commercially available. These employ diaphragms which have circular slots or plural spiral slots. There are, however, no
  • spiral slotted discs having many turns, say four, presently employed in relays, so that the latter represent highly elongated, but compact reeds.
  • the spring device or elongated reed of this invention can be advantageously utilized in a relay which duplicates the present relay'exce'pt in that mercury isomitted,
  • a mercury film is one inwhich the position andshape of. the liquid'mercury do not change with respect to the solid.
  • a mercury layer is one in which the shape ofthe. mercury changes but the mercury remains on average in contact with the-solid, despite changes of attitude of the surface, or subjection thereof to shock or vibration.
  • a mercury pool is one. inwhich both the shape. and location of the mercury change ona statistical and transient basis, the pool, at least as a whole; not being relatively permanently attached to a wettablesurface.
  • mercury When a mercury relay operates, mercury flies .in all directions for each impact between the contacts. In addition, mercuryis displaced due to forces, i.e., those of gravity, vibration and shock, temperature gradients and forcessof surface tension. It is essential that a mechanism-be present in a mercury relay for relocating mercury which has been. displaced, to locations such that contacts will not be short circuited,'andwin the present system this must occur regardless of switch rattitude.
  • cap and header inner surfaces can be improved in respect to surface tension if lined with spiral elements, or withfine mesh screening or the like.
  • the enclosure of the presentinvention can be resistance welded closed, and this can be .done in a.-250 p.s.i. hydrogen atmosphere, at low cost.
  • the Donathdeviceas presently designed cannot be-welded closed, and hence cannot enclosehigh-pressure gas.
  • the present device can be made large, and therefore capable of carrying high current, which is not true of the Donath unit.
  • the Donath unit is. a high-precision unit, in terms of fabrication techniques and thereforetends to be expensive.
  • the present unit is extremely inexpensive because it lends itself to mass production.
  • FIG. 1 is a view in section'of a switch according to themvention, which is monostablein open condition and whichcan be closedby applying a magnetic field, as'by means-ofaperman'ent magnet;
  • FIG. 2 is a view in section'of a modification ofthedevicerof FIG. 1, having two stationary contacts;
  • FIG. 3 is a view in section of an electromagneticmercury relay according to the invention; biased open'and closedwin responseto coil energization;
  • FIG. 4 is a view-in section of a bistable single contact electromagneticmercuryrelay according to the invention.
  • FIG. 5 is a view in'section of a bistable mercury relay
  • FIG. 6 is a view in plan of a spiral armature according to the invention.
  • FIG. 7 is a view in section of the armature of FIG. 6, ener tion, having a mercury wettable internal enclosure walls covered with nonwettable screen, to increase the net linear length of wettable surface.
  • 10 is a header cap fabricated of nonmagnetic material which is internally mercury wettable.
  • a nonmagnetic header 11 which is internally mercury wettable.
  • the header 11 and its cap 10 are welded together by a circumferential resistance weld 12.
  • a contact pin 14 in the form of a cupronickel cored rod; other metals may be employed for the core, so long as they provide a mercury wettable recess, the outer layer of core is a nonwettable covering 15 which extends, farther than does the core, interiorly of the envelope E formed by header l1 and cap 10.
  • the pin 14 is magnetic and is insulated from header 11 by a glass seal 16 which is nonwettable.
  • a spiral armature 17 is welded to the inside of the header cap 10, at its outer terminal 18.
  • the spiral armature 17 is a multitum spiral and in fact the spiral acts as a long reed having its movable terminus 20 at the center of the spiral.
  • the length of the spiral may be about 3 inches, whereas the diameter of the spiral is about inches.
  • the spiral 17 is treated to be mercury wettable, and the space between the spiral l7 and the inner surface of header cap is filled or largely filled with mercury, this space being fillable by a layer of mercury.
  • the space between the turns of the spiral are also filled with mercury (as is the interior surface of the spiral) because of the closeness of the spacing (0.0075 inches).
  • the only surfaces within the envelope E which are not mercury wettable are (1) the surface of insulator 16, and the outer surface of contact pin 14.
  • the core of the contact pin is mercury wettable but its inner end is set back slightly from the inner end of the pin 14, so that the core never physically contacts the spiral armature, but the core does carry mercury and hence can make proper electrical contact with the armature.
  • the spiral armature 17 can now be brought into contact with the inner end of contact pin 14 by means of a magnetic field produced by a permanent magnet M, when the latter approaches the switch.
  • the spiral armature can be maintained in open position by its own resilience, but preferably this is done by a circular radially magnetized bias magnet 21 mounted on a rod 22 axially secured to header cap 10.
  • a circular radially magnetized bias magnet 21 mounted on a rod 22 axially secured to header cap 10.
  • Use of a symmetrical magnetic field provides a uniform bias on all turns of the spiral l7, tending to pull the spring away from the contact.
  • the spring for some designs, would move until stopped by the inner wall of the cap 10. If this results in sticking, or implies too great a movement, a nonwettable projection can be supplied to provide a stop (not shown).
  • FIG. 2 is illustrated a double ended relay, i.e., one having two stationary contact pins 30, 31 and a single spiral armature 32.
  • the enclosure E includes a nonmagnetic header 33 and a nonmagnetic cap 34, which are welded to form a cylindrical enclosure E at joint 25.
  • the total diameter of the header in one design is 0.325 inches. All other dimensions are to scale in the drawing.
  • the contact pin is made of copper alloy cored sealing alloy, nonmagnetic, while contact pin 31 is copper alloy cored sealing alloy, magnetic.
  • the contacts are mercury wettable only at their cores as 36, 37, which are slightly recessed at 38,39, and extend into the enclosure E via glass beads 40, 41.
  • the end of armature spring 32 normally contacts contact 30, because so biased by permanent magnet 21,
  • FIG. 3 illustrates the structure of a form A relay, i.e., one which is normally open, and can be closed by energizing a coil 48 mounted on pin 31.
  • FIG. 4 illustrates how the switch of FIG. 3 can be converted to a relay which latches closed, because of bias magnet 45, but is normally open, by the addition of energizing coils 46, 48.
  • FIG. 3 is essentially the same as FIG. 1 in principle, but is drawn to scale, the diameter of the enclosure being 0.325 inches. Accordingly, the small numerals of reference are employed in FIGS. 1 and 3.
  • FIG. 3 shows the location and quantity of the required mercury layers a bit differently than in FIG. 1, but this occurs as gaps from armature to wall are varied.
  • FIG. 5 A form C relay is illustrated in FIG. 5, which is distinguished from FIG. 2 in that both contact pins must be magnetic, whereas this is optional as to pin 36 in FIG. 2; and the armature 17 is centered, so that the switch is normally open at both contacts.
  • Two coils 46, 48 are employed, and two permanent magnets 45, 45a, identically radially magnetized to make a latching bistable switch. I-Iere magnets 45, 45a must be strong enough to latch when the armature is deliberately activated.
  • FIG. 6 illustrates an effective single turn spiral, formed by etching or stamping a spiral slot 50 in a thin disc of magnetic metal, plated or treated to be mercury wettable, and employs I a 0.0075 inch etch through width and a 0.020 inch land 51.
  • the spiral is generated in terms of concentric circles joined by straight lines, and therefore is not a true geometrical spiral. This is for manufacturing convenience.
  • plural spirals could be employed, but there is considerable advantage in employing one spiral in that this provides the most flexible and most sensitive construction, in that it corresponds with a reed of maximum length.
  • each reed is short, relatively, and therefore stiff, relatively.
  • the total number of turns utilized in the spiral depends on the sensitivity desired, and can be controlled, as can spiral thickness, spiral width, material temper, and the like.
  • the appearance of the spiral armature in process of being pulled can best be indicated as in FIG. 7, which is exaggerated.
  • the spiral is distorted since its outer edge is held against motion, while its center moves into contact with the end of pin 14.
  • the latter has a recessed, mercury wettable core 15, but a nonwettable outer layer 15a. Due to the recessing it is the nonwettable end 15b of the pin 14 which is impacted by the armature.
  • the recessing is sufficiently shallow that a drop of mercury can contact the center 52 of armature 17. When fully actuated the center 52 will contact the end 15b of pin 14.
  • the enclosure header and cap, 80, 81 are fabricated of ceramic, the inner walls of the enclosure being provided with a wettable layer of screen, 82.
  • the relays of FIGS. 8 and 9 may utilize the operating and structural features of therelays of FIGS. l-5, or stated otherwise, the enclosures of FIGS. 8 or 9 may be utilized in the systems of FIGS. 1-5 inclusive at will.
  • permanent magnets 85 are employed to maintain-the-armatures l7 biased planar. This is an expedient usable in any of the relays of FIGS. 1-5. It is adequate. to employ rodmagnets for the purposebut circular magnets encompassing the enclosures are more effective.
  • the switch is extremely sensitive, it can be controlled'by a permanent magnet rather than by a coil. If the permanent magnet is mounted on a moving member, the combination then can be considered a limit switch requiring no physical contact (see FIG. 1
  • a permanent magnet can be used to move the armature in'either direction, depending on the location of the magnet relative to the armature.
  • the magnetafield is symmetrical with respect to the center line or axis of the armature, the presence of the magnet always attracts the armature towards the magnet. But if the field is asymmetrical or off axis repulsion can occur, or attraction.
  • the armature when viewed along a radius and when magnetized presents a linear array of North and Southpoles. If the array. is approached by a North pole, off its axis, that North pole may be proximate a South pole and cause attraction or proximate a North pole and cause repulsion.
  • the armature may be welded into the enclosures.
  • a mercury switch comprising a concave dish of nonmagnetic material impervious to mercury
  • said diaphragm being a spiral spring having an axis
  • said diaphragm having a mercury wettable surface
  • said stationary contact having its contact end facing said helical spring and being mercury wettable and being fabricated primarily of magnetic material
  • a relay comprising an envelope
  • contacts comprising a spiral spring armature and a stationa ry pin contact opposed to said spiral spring'armature, said contacts including opposed mercury wettable surfaces,
  • the total quantity of mercury within. said. envelope being only sufficient to form athin layer of mercury on saidmercury wettable surfaces and. insufficient to form apoolof mercury in addition to said thin layerrof mercury for any attitude of said relay.
  • a mercury relay comprising a hermetically sealed envelope
  • first and second ferromagnetic pins extending insulatedly through said envelope in opposite directions toward said flat plate
  • said envelope including mercury nonwettable insulators: through which said pins extend, the interior surfaceof said envelope exclusive of said insulators and the surfaces of said flat plate and'at least the inner ends of said pins being mercury wettable, and there being only sufficient mercury within said envelope toform layers of mercury covering said mercury wettable surfaces, but insufficient mercury to form a poolin addition to the mercury of said. layers, which pool might cover the inner surfaces of one of said insulators.
  • said insulators are glass
  • said pins include copper alloy cores which are mercurywettable and have a covering of magnetic material, said cores being undercut with respect to said covering whereby only said covering is impacted by said armature.
  • said envelope is made of two concave metallic headers welded to leave a cavity within which said armature subsists, said arma' ture being secured only adjacent its edge to at least oneof said headers.
  • a magnetic relay comprising ahermetically sealed metallic enclosure including a header and a header cap,
  • An attitude insensitive mercury relay comprising a cylindrical enclosure having end plates and having amercury wettableinterior surface
  • a mercury wettable thin flexible armature located interiorly of said enclosure and extending transversely of the axis of said cylinder
  • said mercury wettable interior surfaces including a portion which is unwettable by mercury and which surrounds said stationary contact
  • An attitude insensitive mercury relay comprising a hermetically sealed ceramic enclosure having generally parallel end plates and internal mercury wettable surfaces,
  • At least one stationary mercury wettable contact extending through one of said end walls into contact with said flexible armature when said flexible armature is flexed toward said stationary contact
  • a relay comprising an envelope
  • said conducting surfaces including relatively movable areas substantially wettable by said liquid, and including one movable contact constituted of a thin resilient magnetic diaphragm secured at its rim to said envelope, the quantity of said liquid within said envelope being substantially adequate to cover said substantially wettable areas with a thin layer of said liquid and inadequate to fonn a permanent and substantial pool of said liquid in addition to said layer regardless of the attitude of said relay.
  • a switch comprising an envelope
  • a contact within said envelope including a resilient diaphragm anchored at its rim,
  • said contacts including mercury wettable surfaces
  • a total quantity of mercury within said envelope being only adequate to form a thin layer of mercury on said mercury wettable surfaces held to said mercury wettable surfaces by surface tensions, said surfaces interchanging mercury during operation of said switch.
  • a switch comprising a concave dish of resistance weldable metal, a magnetic armature located in said dish and electrically connected to said dish, a stationary contact, an insulator extending insulatedly through said dish from exteriorly to interiorly of said dish, said stationary contact extending through said insulator, a closure of resistance weldable metal peripherally welded about the periphery of said dish to form a hermetically sealed enclosure, wherein said magnetic armature and interior surfaces of said enclosure include mercury wettable areas and wherein said insulator is mercury unwettable, and wherein a quantity of mercury within said enclosure is only sufficient to sustain a thin layer of mercury on the mercury wettable surfaces therein but insufficient to form a pool of mercury, whereby said switch is position insensitive.
  • a mercury switch comprising a concave dish of metal impervious to mercury
  • said diaphragm having a mercury wettable surface
  • said stationary contact having its contact end facing said spiral spring and being mercury wettable
  • said envelope is comprised of a header of resistance weldable metal and a cap of resistance weldable metal, said header and cap being resistance welded together about their peripheries to form said envelope as a hermetically sealed envelope.
  • a mercury relay comprising a hermetically sealed envelope
  • a ferromagnetic annature for said relay located interiorly of said envelope
  • first and second ferromagnetic pins extending insulatedly through said envelope in opposite directions toward said armature
  • said envelope including mercury nonwettable insulators through which said pins extend, the interior surface of said envelope exclusive of said insulators and the surfaces of said flat plate and at least the inner ends of said pins being mercury wettable, and there being only sufiicient mercury within said envelope to form layers of mercury covering said mercury wettable surfaces, but insuflicient mercury to form a pool in addition to the mercury of said layers, which pool might cover the inner surfaces of one of said insulators.
  • a relay comprising an envelope
  • said conducting surfaces including relatively movable areas substantially wettable by said liquid, and including one movable contact constituted of a thin resilient magnetic armature secured at at least one point thereof to said envelope, the quantity of said liquid within said envelope being substantially adequate to cover said substantially wettable areas with a thin layer of said liquid and inadequate to form a permanent and substantial pool of said liquid in addition tcTsai d layer regardless of the attitude of said relay.
  • a switch comprising a metallic envelope, an armature within said envelope, a stationary contact extending through said envelope,
  • said contact and armature including opposed mercury wettable surfaces
  • At least one mercury unwettable surface within said envelope insulatedly separating said contact and envelope
  • a total quantity of mercury within said envelope being only adequate to form a thin layer of mercury on said mercury wettable surfaces held to said mercury wettable surfaces by surface tensions, said surfaces interchanging mercury during operation of said switch.

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  • Physics & Mathematics (AREA)
  • Electromagnetism (AREA)
  • Contacts (AREA)
  • Electromagnets (AREA)
US66534A 1970-08-24 1970-08-24 Mercury switch Expired - Lifetime US3646490A (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
US6653470A 1970-08-24 1970-08-24
US13495971A 1971-04-19 1971-04-19

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US3646490A true US3646490A (en) 1972-02-29

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Application Number Title Priority Date Filing Date
US66534A Expired - Lifetime US3646490A (en) 1970-08-24 1970-08-24 Mercury switch

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US (1) US3646490A (cs)
BE (1) BE777458A (cs)
CA (1) CA952563A (cs)
DE (2) DE7202348U (cs)
FR (1) FR2133559B1 (cs)
GB (1) GB1378164A (cs)
NL (1) NL7117337A (cs)
SE (1) SE383577B (cs)

Cited By (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3900820A (en) * 1974-02-25 1975-08-19 Bell Telephone Labor Inc Line supervisory circuit
US3978301A (en) * 1975-07-31 1976-08-31 Fifth Dimension Inc. Mercury tilt switch
US4099040A (en) * 1976-03-30 1978-07-04 Fifth Dimension, Inc. Mercury type tilt switch
US4103135A (en) * 1976-07-01 1978-07-25 International Business Machines Corporation Gas operated switches
US4156216A (en) * 1977-10-06 1979-05-22 Allen-Bradley Company Mercury switch relay
US4683355A (en) * 1986-12-09 1987-07-28 Fifth Dimension Inc. Position insensitive shock sensor
US20030214374A1 (en) * 2002-05-14 2003-11-20 Duraswitch Flex armature for a magnetically coupled switch
US20030234166A1 (en) * 1999-12-22 2003-12-25 You Kondoh Switch device and method of making same

Family Cites Families (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE1614671B2 (de) * 1967-12-04 1971-09-30 Siemens AG, 1000 Berlin u. 8000 München Lageunabhaengiges quecksilberrelais

Cited By (11)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3900820A (en) * 1974-02-25 1975-08-19 Bell Telephone Labor Inc Line supervisory circuit
US3978301A (en) * 1975-07-31 1976-08-31 Fifth Dimension Inc. Mercury tilt switch
US4099040A (en) * 1976-03-30 1978-07-04 Fifth Dimension, Inc. Mercury type tilt switch
US4135067A (en) * 1976-03-30 1979-01-16 Fifth Dimension, Inc. Tilt switch and holder
US4103135A (en) * 1976-07-01 1978-07-25 International Business Machines Corporation Gas operated switches
US4156216A (en) * 1977-10-06 1979-05-22 Allen-Bradley Company Mercury switch relay
US4683355A (en) * 1986-12-09 1987-07-28 Fifth Dimension Inc. Position insensitive shock sensor
US20030234166A1 (en) * 1999-12-22 2003-12-25 You Kondoh Switch device and method of making same
US6797901B2 (en) * 1999-12-22 2004-09-28 Agilent Technologies, Inc. Switch device and method of making same
US20030214374A1 (en) * 2002-05-14 2003-11-20 Duraswitch Flex armature for a magnetically coupled switch
US6842098B2 (en) * 2002-05-14 2005-01-11 Duraswitch Industries, Inc. Flex armature for a magnetically coupled switch

Also Published As

Publication number Publication date
BE777458A (fr) 1972-06-29
DE2202881A1 (de) 1972-11-09
DE2202881B2 (de) 1976-03-11
DE7202348U (de) 1974-10-24
GB1378164A (en) 1974-12-27
FR2133559A1 (cs) 1972-12-01
SE383577B (sv) 1976-03-15
FR2133559B1 (cs) 1976-12-03
NL7117337A (cs) 1972-10-23
CA952563A (en) 1974-08-06

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AS Assignment

Owner name: PNC BANK, NATIONAL ASSOCIATION, NEW JERSEY

Free format text: SECURITY INTEREST;ASSIGNOR:FIFTH DIMENSION, INC.;REEL/FRAME:009103/0531

Effective date: 19911206

AS Assignment

Owner name: PNC BANK, N.A., NEW JERSEY

Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNOR:FIFTH DIMENSION, INC.;REEL/FRAME:010144/0181

Effective date: 19990712