GB2390236A - Electrical contact design - Google Patents

Abstract

An electrical contact 400 comprising a moveable, electrically conductive, contact pin 420 mounted within an insulating body 410. An electrically conducting path, from a contact head 430 of the contact pin 420 to an interior of a base or chassis 310 is created only when sufficient downward pressure is placed on the contact head 430. The electrical contact 400 may form the contact between a cordless telephone handset 320 and its respective recharging base portion 310.

Description

úLECTROSTAT1C DISCO - GE

ENHANCED CHARGE CONT.CI DESIGN

UOOl} BACKGROUND OF THE INVENTION

Field of the Invenuon

00021 The present Invention relates generally to electrical contact consrucuons and, more particularly, to electrical contact constructions for cordless lephonc handset apparatus. Backrowld of the Invention 06031 Figure 1 is a schematic diagram showing a known cordless telephone.

Conventional cordless telephone 10 Includes base unit I 1 and handset 12. TO lets half of Figure 1 shows base unit I I without handset 12 placed vermin it. The new half of Figure 1 shows handset 12 rested within base unit 11.

U004l Base unit 10 includes battery charging equipment 19 and a cradle caved that is configured to receive handset 17. The cradle cavalry has eleemcal contacts 13 dial are suitably disposed within the cradle cavity, so that upon placcTnen' of handset 19 In the cradle cavity, electrical contacts 13 physically come into contact avid corresponding electrical contacts 14 oThandse: 12. Battery charging equipment 19 use base urns I I (and possibly, in handset 12) is then activated lo supply current lo the battery in handset l? lo recharging the basics.

51 In many such handset consucuons, elecmcal contacts 14 in the bortom portion of}antsy 12 arc continuously coupled Eclectically with the Nepal electrical c rcuiu, (not shown) of handset 1. Because of this consu Scion, it is often possible that during the use of hardsc 1', He operator, and, in rum, handset 12, may acquire a substantial static electrical charge. During the act of placing handset 12 into *c cradle cavity of base unit 11, a substantial clecrostaic discharge (ESD) may occur due to the static energy that Is discharged from}dj - 1

12 and/or the operator, into base unit 1 1 The discharge may result in damage to The circuitry either or both of handset 12 and base unit 11.

tOOQ6] Accordingly, known cordless telephone constructions have Typically required the presence of special circuitry Vivian base unit 11 to dissipate OT orhenvse address the electrical energy of a discharge tO protect the fimctonal circuitry of Telephone 10. Such protective circuits or over structures (mechanical andJor electrical) often significantly add To the complexity and cost, as well as the physical size, of The Telephone cornponens.

10007J In addition, The charging contacts in base unit 11 of base 1, need To have a spnag-acoon interface between contacts 13 of base it 1 1 and electrical contacts 14 of handset 12. The sprg-action interface enables contacts 13 to be};ept in continuous contact Aim handsc contacts 14 The spnog-acuon incrfacc also pennies contacts 13 rhemselvcs lo be moved to address Me clearance between the cradle cavity of base urut 11 and handset 12.

oUo8l ConiacEs 13 apply a spring force exerted by shin sheet of McCall 15 Thin sheer of metal 15 con be, for:xample, about 0.15 mm Wick. Preferably, thin sheet of metal 15 is made of a phosphorous bronze, nickel-plated sheet. Thin sheet of metal 15 supports contacts 13 at one end end is connected To Me Enamor of base unit I 1 a' the other end. Metal sheet 15 provides for an elastic reciprocal travel within a controlled travel stroke. Metal Shea: 15 may well be durable enough for the service life of Telephone 10. Nevcrtheless, there may exist non-uuformties In the spring force of individual charge conracrs due to odious fabncaion "d quaJiy control issues.

0009] Such thin sheer metal consucion for};nown resilient corsac: support structures leads to a relatively non-robust element.}Iandlng dunug manual fabrication processes may compound irregularities in in:i1 defonnaion. In addition, such thin sheet metal elements may complicate the assembly process, incremg: the assembly rime and assembly costs.

OGIO] Such whist sheer metal contact supports arc typically attached to base unit 11 by screw fasteners 16 (see Figure 2), which may exert forces on metal sheet 1 S ha: may skew ho Alignment of charge contacts 13 within Its chassis aperture, such that contacts 13 may require adjustment on a poenually individualized beets (see left half of Figure 2). Such known contacts are also susceptible To rnisalgnnen' due to - 2

operator misuse, or attempts To clean the charge contacts with a pen (see righ' half of Figure a).

|00111 A Typical known electrical Contact consTrucuon incorporates metal contact head 18 that is a protrusion That leans through opening 17 in base IT I 1. Ths consuucuon requires clearance between contact head 18 and Me chassis to prevent contact head 18 from being snack because of frictional force, in case correct head 18 rubs against do base chassis. The light spring force available in *tin sheet metal 1 S may not be adequate To ensure that in We even' of such frictional contact between contact bead 18 and Me chassis, contact head 18 will be reliably pushed bacl; up through aperture 17 in The chaSS}S7 \0 ARC specified position. To avoid imposition of such Dicuonal forces, a visible sap may be created Thai may persni the pcnctranon of liquid, dust, etc. Such a sap may become even more pronounced f;when Me eleemcal contact becomes misaligned. Damage and premature degradation of base U=T 1 I may be a result U0121 'an addition, a contact for a base U=T for a cordless telephone should be robust enough lo resist and Missed a certain amount of possible abuse by rbe owner 3) Accordingly, Acre is a reed for an clecmcal contact consrucuon Thai may be employed in the envrorune of a cordless Telephone handset and a base unit, as Bell as in other cavirorunens, in which the elecncal contacts have an Improved design a: provides a degree of protection regains' dasnage Through Me propagation of a static elecncal discharge 00141 Funhennorc, it would also be desirable To provide an electrical contact consnucion rha' is provided High a robust design To provide for a reliable operation over an expected life cycle of rho Telephone.

PUBIS' Moreover, it would bc desirable TO provide an electrical contact cons con that has an advantageous ease of assembly.

00161 These and odor desirable characteristics of Me nvennon will become apparent In light of the present spectficanon and drawings.

SUMMARY OF THE lNVENTlON

00171 One embodiment of We tnvennon is an electrical conic: that reduces elecmostanc discharge In eleconc devices. The elecncal contact includes a contact head, a contact pin, a body, a electrical connection plate, and a spring. We contact head is made of a nonconducive maenal. The contact pin is made of a - 3

conductive material. The contact pin includes a top end, a soon, and a seminal point. The contact pin is embedded within slie contact bead so as to provide an electrical path from die fop end to the temunal point. The body is made of a nonconductive matenal. The body is configured u, receive the stern and the terminal point within a cavity of Me body. The electrical connection plate is attached to bonom portion of We body. The spring surrounds The stem of He cons&c: pin. The spring is disposed vv;hn the body such Ho an air gap exists benvecs' Tic electrical connection plate and the temunal point of He contact pin when He spring IS compressed.

00181 Preferably, the contact head rusher uncludes one or more. legs. Preferably, the contact head Ocher Includes a [OOt on each of He one or Mae legs. Preferably, the cone head archer includes a bridging portion, and the contact pin is disposed within the bridging portion. Preferably, rbe contact pin further includes one or more lateral projeenons. The one or more lateral projee:ons of He contact pin are embedded within the contact head. Preferably, the spring is disposed benvc" a Aged surface of body and the contact head. Preferably, He contact pin touches the elecneal connection plate when hc spring is compressed by a force exerted on the top end of the contact pin. Preferably, He electrical connection plate fimher Includes one or more cars configured to attach the electrical connection plate to the body Another cmbotunent of Tic invention provides a base of an e]ectrouc device.

The base includes an internal circuit and an electrical contact The electrical cone Includes an electrical connection plate and a contact pin. The electrical connection plate is electncally connected TO the inema1 ciscuin The contact pail is configured to move beaver a first position and a second position. In the first position, the contact pin is clecmcally separated from the electrical connecuen plate by air gap. In the second position the contact pin touches the electrical cosnecrion plant.

0 1 Preferably, the electrical cone bother Includes a spring. The spring is configured snainn He contact pin in the first position Ruben the spring is in an uncompressed state. Preferably, the spring is fi=her configured to be compressed by a force exerted on a lop end of the Contact pin to move the contact pin from He first position to the second position. Preferably, Me electrical contact fit -4

includes one or more prongs Preferably, the base funkier Includes one or more side apertures That are configured to receive the one or more prongs of hc elecncal contact.

0211 In another cmbodment, the mvennon provides a cordless relephoDc that Includes a handset, a base usut, and an decmc&1 contact. The handset has a contact point a' a bonom portion of the handle. The base unit has an infernal circule configured lo be electrically connected to the contact point when the handset is rested within a cradle cavity of the base unit. Me electrical contact is artached to the cradle cavity. The electrical contact includes a contact put, a spring, and an electrical connection plate. The electrical connection plate is elecmcsly cormecet so the inkmal circuit of Me base unit. The spring maintains an air gap between die contact pin and the elec=,cal conneculon pled when the handset is not in the cradle cavity When Me handset Is placed in the cradle cavity, she contact point touches the contact pin and the handset compresses the spring so that the contact pin touches the electrical connection place.

00221 Preferably, Me elecmcal cone Ocher includes a contact head and a body.

Preferably, Me contact head and Me body are made of a nonconductive mineral Preferably, the contact pin is embedded within Me contact head such that a lop end of the contact pin is exposed above the contact head to enable electrical connection bervecn the contact pin of the elecncal contact and The contact point of the handset. Preferably, the contact pin fished includes a scent. Preferably, the spring surrounds Tic stern.

BRIEF DESCRIPTION OF THE DRAWINGS

10023] Figure I is a schematic diagram showing a conventional cordless telephone and its electrical contact design.

00241 Figure 2 is a schematic diagrmn showing potential drawbacks of the concanonal electrical contac'arrangernent.

U0251 Figure 3 is a schematic diagram showing a prefened embodiment of the invention in which cordless telephone 300 includes electrical contact 400 of the invention. 00261 Figure 4 is a schemarc diagram showing a perspective, exploded view of electrical contact 400 according to a preferred embotmenr of the invention.

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I4ly- I OUU' U:: LOPm r I U111 00271 Fgure 5 s a firon' elevanon view Df electrical conacr 400, vhich s shown in s "semblcd configuraiion.

100281 Figure 6 is a ngh-sde elevaton view of assembled electrical cont&ct 400.

1 91 Fgure 1 is a OM cross-s=tion vc of electrical contr 400.

100301 Fgure 8 is a nght-side cross-section ViC,b of elecrical contact 400 100311 Figurc 9 is a schematic diaam ihowing a perspecrive vieu, of body I according o a prefrred embodunent of c inventiorn 10031] Figure I O is a fron' elevation view of body 410.

100331 Figure I I is a rop plan new of body 410.

10Q341 Figure I s a bonon view of body 410.

5] fgure 13 sanght-sideelevationvicuofbody410.

100361 Fgurc 14 is a lefi-side clevaton view of body 410.

10037] Fgurc 15 is a onr cross-section vievv of body 410, taken along 1ne CEN CEN sbown in Figure 14 00381 Figure 16 is a righ'-sidc cross-secon vie\v of body 410, alcen along 1ne B-B shourn in fiEpure 15.

0039] Figurc 17 is a schanaic diagram shovng a side elevaion vew of contac pin 4to accorting TO a preferred embodiment of rhe invennon.

0U40| Figure 18 is a front elevation view of contac pm 420.

00411 Figure 19 is a schematc diagn sho g a perspecrive view of conracl head 430 accordirg to a preferred ernbodirnent of The invcurion.

00421 Figurc 20 s a fiont elevanon view of conact head 430.

1 31 Figuse 21 is a tDp pi1 VIC\V of conct hc 430.

t0044] Figure 22 is a boT:om vew of conact head 430.

100451 Figure 93 is a right-side elevsion vev of conracr head 430.

|U046| Figure ?4 is a lefr-side cross-secon view of conacT head 430.

1871 Figure 95 is honT cross-sec',on view of conTacT head 430, Taken along line SIDE-SII:iE shown n Pigurc 24 OD481 Figurc 76 is a schernaTic daarn of a perspecTivc view of electrical connection plate 440 acccrding ro a preferred embodunen of hc invenrion.

00491 Fgur 27 is a top plan vi of elecical connection plate 440.

0050] Fgure 28 is a bont elevation view of e}ccFical connecron plate 4sO 511 Fgure 29 s a rear elevaron view of electrical connecion plate "0.

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lO0521 Figure 30 is a nght-side elevanon viva of elecmcal connection plate 440.

3] Figure 31 Is a lef'-side elevation vcv of eIecmcal connection plate 440.

[OOS4] Figure 32 is a fragmentary side elevation view of spring 450 according TO a preferred embodiment of the invention DEI^ll li:D DESCRIPTION OF TtiE DRAWINGS

UU55l While this invention Is susceptible of embodunent in many different forms There is shown in Me drawings ant will be described herein in detail a specific embodiments with Me understanding That the preseM invention is to be considered as an exemplification of Me Disciples of The. invention and is not intended to limit die uvennon to the embod==t illUsTr8TCd.

[0061 The preferred embodiment' of the invention is directed TO an elecncal conrac construction. The electrical contact incorporates movable neTal connection component The moveablc componer T is resiliently mounted within an insulating body. In the Contex' of an electronic device (e g a cordless telephone) that Includes portable unit (e.g. tile handset) and base (e.g the base unit of Me cordless telephone) the electrical contact of dle invention cast be Incorporated e g. es a component of the base. An elecmcally conducting Pam from a contact head of Me clecrmcal contact to the interior of the base is created only what the portable Ural has been positioned within the base.

00571 Preferably The present nvenuon can include an nlegraTed ON/OFF switch within a single compact device For example when a handset of a cordless telephone is placed Filly or substantially fully toum on and within a cradle cavity of a base unit of the cordless telephone hc weight of the handset pushes hc contact device into Me ObI or electrically conducting configuration. In The open cofiguraon or the OFF position hc handset is either absent Mom flee base unit.

or the handset Is only slightly touching such ha' the candor is not 11y depressed.

In hc OFF position an air gap exists v'hm The contact assembly itself creating an open circuit condition. The open circuit condition tends to rcLIuce the llcchhood of an elecrrosranc discharge from occusnug A' Tic leas: The open circuit condition requires The charge to cross The air gap and dissipating. at least in part through ionization of hc air In the air gap in the process of The discharge.

BU581 To the Mint that. any numerical values mcrallurgical compositions or other specific technical details are provided in the figures or in The descnprion They are

( given by way of example anal Me present mvenuon is no' unended to be lionized thereto, as one of ordinary skill In die an, having the present disclosure before

hem, will be able to malce modifications and vanaions in the invention, without depamug hom We scope of the invention.

100591 Figure 3 is a schematic diagram showing cordless telephone 300 that includes a preened cmbodmen: of elecmcal contact 400 of invention. Cordless telephone 300 includes base unit 310 and handset 320. Base Alit 310 includes electrical conuc' 400 a' me bonom of cradle cavity 311. In hc non-operating condition (first position) shown on she let* side of Figure 3, contact pin 420 (more clearly shown in Figure 4) is separated Mom electrical connection plate 440 (more clearly shown in Figure 4) by air gap 330. In the charging condition [second positron) shown an the right side of Figure 3, terminal point 428 (more clearly shown In Figure 4) of contact pin 420 is in contact vain elecncal conuccrion plate 440 and Mere Is no air gap. Thus, in the non-operating condition shown on the left side of Figure 3, circuit 31, of base unu 310 is open." On the other hand, circuit 31, is closed" in the charging condinon shown on the right side of figure 3.

Although the preferred embodying: includes electrical contact 400 as pan of base unit 410, modificanon can be made so ha: clecrrical contact 400 can be included as part of'nasdset 320.

060] Preferably, air gap 330 can be calibrated lo be about 2 mm. The 2 An air gap can defend KV. In other words, circuit 312 can bear about Key of electrostatic discharge or Hi-Po (High Potenrial) test. Preferably, contact head 430 moves down about 3.4 mrn to press and touch elecmcal cornecuen plate 440 when hands 320 Is put an cradle cavity 311 of base UDiT 310. Handset 320 is electrically connected, via contact pond 39', lo circuit 312, via electrical connection plate 440, when finely placed In cradle cavity 311.

00611 As shown us Figure 4, electrical contact 400 includes body 410, contact pin 420, contact heat 430, clecmcal connection plate 440, and spnag 450. When Filly assembled as shown in Figures 5, 6, 7, ant 8, cone, cr pin 420 Is surrounded by spnog 450. When assembled, contact pin 420 and spring 450 are located Willis, cavity 413 of body 4 l 0. figures 7 and 8 indicate char subsanrially the entire length of stem 426 of consacr pin 430 Is surrounded by spring o'50. AS shown in Figures 7 anc1 8, top end 422 of contact pin 420 is embedded vihin bridge portion 432 of - 8

contact head 430. Preferably, contact pin 492 includes one or more lateral protections 424 to provide additional friction. between TOp end 422 and bridging portion 432. As shown in Figures 8 ant 9, Top end 422 is exposed on top surface 431 of contact bead 430. Top surface 431 guides the positioning of the handset on the base, by providing pin and hole" relanonshp. and secures The aligrunen of the handset and the base. A width of Top surface 431 can be designed so Baa an artificial finger, which is a steel rod having a rounded end, of the UL H-Pot test cannot push Contact head 430 so as elecncal connection cannot be established with the internal circuitry. Air gap 330 between Contact pin 410 and electrical connecusn plus 440 prevents arcing. Further, top surface 431 can withstand a force exerted by The anifical finger during the Hi-Poe Test.

0062] Figures 9, 10, 1 1, 12, 13, 14, 15, "d 16 depict different views of body 410.

Preferably, body 410 is fabnceed Bom an electrically insulaimg mineral. For example, body 410 can be made of a suitable plastic rn&rerial. Other electrically insulating maenals may be used.

C31 BodyS10 includes left shoulder412 (see Figure 15), cavry413 (see Figure 13), right shoulder 414 (see Figure 15), front 04rwardi'projecring bided prong 416 (See Figure 13), rear ourwardlyproJecting biased prong418 (see figure 13), front minor barb 411 (see Figure 10), and teas minor barb 415 (see Figure 16).

Front minor barb 411 and from prong 416 arc located on one side of body 410 (c g., the *on' side), while rear minor barb 415 and prong 418 arc located on the opposite side of body 410 (c.g., the rear side) Cavity 413 is surrounded by prongs 416, 418 and shoulders 412, 414.

0064) Contact pin 420 Is electrically conductive. Contact pin 420 is preferably fabricated from a conductive material, such as a metal or an alloy. For example, contact pin 420 is preferably made of copper with gold plating. Preferably, the rnatesal is about 0.8 ram copper with about 3 microns copper plus about 5 microns gold plating. Other materials may be Unplowed. AS shown in Figures 17 and 18, a preferred embodiment of contact pin 420 Is elongated with top end 422, stem 426, and terminal point 498. Top end 422 preferably has a T-shape as indicated in Figure 17 and Figure '3. Preferably, contact pin 420 Includes one or more lateral projections 424. Stem 426 is about the saline length as spun" 450 When spun" 4SO Is not compressed Preferably, contact pin 420 is tree from bows and grease.

10065] As sloven in Figure 20, contact head 430 includes shoulder 431, bridging pornon 432, a pair of legs 434, and a pair of outwardly exploding fecal 436. Legs 434 are extended from bridging pomon 430. Each leg 434 includes an outwardly excndng foot 436. Bndging pontoon 4;2, legs 434, and few 436 are preferably an integrated unit. For example, these Components can be molded as an unitary piece.

Preferably, contact head 430 is flexible or resilient such Mat feet 436 can move closer To each other when They are squeezed or pressed Toward each odder, and when the pressure is released, feel 436 moves away from each other to resume the position indicated In Figure 20.

0066] Preferably, contact head 430 holds top cod 422 firmly. Preferably, one or bow lop end 422 and laterally projections 424 are embedded within bridging portion 432. Stem 426 cxents downwardly below fecal 436. As shown in Figure '0, cannel point 428 is located al an elevation lower that those of feet 436.

00671 AS shown in Figure 26, electrical connection plate 440 includes resiliently configured correction pornon 442, a pair of ears 444, operungs 446, and tail 448.

Electrical connection plate 440 is preferably configured to be connected to a bottom portion of body 410. Terminal point 498 of contact pin 490 moves into contact with reslienTJ, configured cosmecsion portion 442. Connection portion 44 preferably has sufficcus length and resiliency to pcs,,,is she accommodation of some variance as to The amount of movement of comae pin 420 and contact head 430, relative TO body 410, upon receipt of handset 390 by bee unit 310. Tail s48 Is provided so serve as an ultimate electrical connection for the contact assembly Preferably, electrical connection plate 440 is free from burrs and grease.

Preferably, the material for plate 440 is phosphorous bronze shas is about 0.' rrun thick wish abous 3 microns copper plus about S microns of nickel plating.

00681 As shown in Figure 32, spring 450 includes sop cud 452 and bosom end 4.

Preferably, when spring 450 is is ITS uncompressed or natural state, she distance between top end 4S2 and bosom end 454 Is about slot same as the length of stem 426. Spring 450 is provided TO sur.roupd elongated stem 426 of contact pin 470.

Preferably, tissance "I-" shown in figure 32 is We natural dsTarcc which Is decided by vendor of span" 450. Preferably, the working navel distance s from about 2.0 me TO about 5.4 mm. Prefembly, TEH working force as 5.4 mm Is about g. Preferably, TEH working force a' 2 trim is about IS g. Prcteably, the - 10

magnum travel point is about 2 mm. The most spnug 4SO can be compressed or shoncoed. is about 3 4 mm. The diameter of spring 4SO is preferably about 2 rum.

The diameter of Tic wire a: fonns spnag 450 is preferably between about 0. 16 mm to about 0.2 mm 10069] To assemble the various components of electrical contact 400 depccd in Figure 4 Into The assembled elecmcal contact 400 depicted in Figures 5, 6, 7, and 8, the following steps may be followed.

1 l Firsts spun" 40 is sleeved over stun 426. In Is manner, as shown in Figures 7 and 8, spun" 450 surrounds Tip 420 so thar upper and 452 of spring 450 comes into contact web a botron' surface of bridging Pomona 432 and lower end 454 of spnng 4SO is located near terminal point 428 of contact pin 420.

00?11 Then, contact head 430 is pushes into cavity 413 of body 410 This can be done by pushing or squeezing fecal 436 Lombard each over and Then guiding them into cavity 413. Bridging portion 423 can Men be pushed in a downwardly motion so that legs 434 moves further down into cavity 413. Once fact 436 pass shoulders 412, 414 of body 410, Use potential energy Tha; is stored in legs 434 due TO previous squeezing, of feel 436 causes feet 436 to return to their nominal positions, which is fi:nher apart Tom each other than what there were being pushed through shoulders 412, 414 The separation of feet 436 from each other al points below shouldm 412, 414 prevents The removal of cor:ac head 430 due to rho inerf=ence of feet 436 with shoulders 412, 414.

00721 Next, IcctocaJ connection plate 440 is pressed onto the 'oorcom of body 410.

This cast be accomplished by aligning cars 444 over minor barbs 41 1, 415. AS electrical connection plate 440 is pushed in an upwardly motion ears 444 pass over minor barbs 41 1, 415. Barbs 411, 415 Men become captured in openings 446 of cars 444 to keep electrical connection plate 440 held against The bottom of body 410. 10073} The inenor of body 410 is appropriately configured so day bottom end 454 of spring 450 bears agamst an inenor, plastic or other non-conducing surface 419 of body 410 (see Figure 8), preventing seminal point 438 of contact pin 420 from touching connection portion 442 of electrical connection plus 440. As shovrn in Figures and 8, air gap 330 exists bevcen enninal point 4,B and connection portion 442 in Me configuration (the firs: position) illustrated. Unless contact head - 11

I - a 430 Is pushed fiercer down (the second position) UdD body 410 (e.g., due TO the vveght of handset 320), air gap 330 exists due lo the po2cnrial energy Ibat IS stored In spun" 450-

00741 Accordingly, any electrical slam discharge that might 'jwnp" Mom contact point 320 of handset 320 would not only have lo leap hc gap Mom handset 390 To top end 422 of contact pin 42G, but also air gap 330 That exists between tenninal end 498 of contact pin 420 and connection portion M2 of clectocal connection plate 440. Moreover, coven once physical contact between handset 320 and top end 422 of contact pin 420 has bum made, static discharge is sull made less potentially damaging, due at least In pan to the psisrence of Tenor air gap 330, until suffclen: depression of conracrhead430ino body410 has occurred.

10075] Once assembly of electrical contact 400 has been completed (see Figures 5, 6, ?, and 8), ii can be pushed through a swrably shaped opening or cradle cavity 31 1 in Me chassis of base unit 310. Base unit 310 Is provided wad side apertures that receive and engage prongs 416, 418 and prevent removal of clectncal contact 400.

Press Fit" tolerance dimensions would be all that Would be required. Because the lover outer portions of electrical contact 400 do not move with respect to hc chassis of base unit 310, Cc is less gap That can occur, thus providing Archer protection against oDdesred infusion of coMaminns into hc interior of base unit 00761 lithe present invention provides several advantageous features. For example, contact head 430;md contact pin 420 form a rigid solid par' Blat Is more robust than the cantilevered weak leaf spring design of prior an contacts. Further, since contact head 430 Ad contact pin 420 form a rigid solid pan, a conducic surface of the coMact pin con be cleaned vithouT damaging elecmcal contact 400, thus extending the life of The device. FurtheTmore, the sisuplicry of contact pin 420 facilitates the plating process. Preferably, contact pin AD Is about 0.8 mm Thick copper, and can he elecoplarcd by B barrel plating process which lends itself To economical mass-producron. The use of The coil spring 4SO Dines a degocr considerable flexibility In dce:Tmnng the desired arnounT of spnng force ha: the contact will employ.By advantageous selection of The wire material and diameter, and overall sprung diameter and other dunensions, a fairly accurate amount of control over the spring ponnance, and win reduced v;maron from spring To - 12

spring, can be achieved. Spring 450 martens elecmcaJ contact 400 In an open circuit configuration, that helps discourage e]ecmossauc discharge and, by virtue of ntemal air gap 330, helps so cause the dissipation of charge. Ire Me even: the electrosanc discharge does occur, it IS dissipated before the current can reach the internal circuitry 312 of base unit 310.

00771 The invention also rununizes she visible gap or clearance berveen the base unit charge comics and she chassis, Thus improving Me appearance of the produce.

The Invention also provides a more robust and reliably assembled produce.

Defonnation of the electuca] and moving components drunk assembly is reduced.

The invention Anther provides a degree of protection against electrostatic discharge. The COD7AC: assembly is provided so Was it can be snapped into a suisabic aperture in a brace chassis, Bus eliminating the use of a deforming screw fastener. In addition, the Invention results In reduction ID assembly costs "d protucuon ume.

00781 The foregoing disclosure of Me preferred embodiments of The present

inversion has been presented for purposes of illustration and descriptor. 1 Is not intended so be exhaustive or to limit the invention to Me precise forms disclosed.

Many variations and modifications of rho embodiments described herein will be apparent to one of ordinary skill in the err In light of the above disclosure. Lyle

scope of the nvenson is to be defined only by He claims appended hereto, and by their equivalents.

[007gJ Fuer, in descnbng representative embodiments of she presens invention, rho specification:nay have prcsenred the method andJor process of the preserve

invmsion as a particular sequence of seeps. However, lo Sac extent that the mewed or process does no; rely on skit particular order of steps set forth herein, The method or process Should not be limited TO the particular sequence of steps deicubed. AS one of ordinary skill in the an would appreciate, other sequences of steps snag be possible. Theseforc, He particular order of the steps se' fork In The pecficanon should not be consumed as lmitanons on The clauns. In addinon, hc clauns directed TO the method Indoor process of Me present invention should no: be [united lo hc performance of their steps in *:c order written, and one slcil]ed In rhc art can readily appreciate that the sequences may be vmed and still remain vvi:n the spans sad scope of the present Invention.

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Claims (1)

1. Pat- 1 À-.-rl', \41iAT IS CLAIMED IS

   1. An electrical contact for reducing electrostatic disclaim composing: a contact head made of a nonconductive martial; a contact pin made of a conducove Maxwell, Me contact pin comprising a top end, a stern, and a terminal point, wherein the contact pin is embedded Within Ihe contact head so as to provide an electrical Pam from the top end to die temune1 point; a body made of a nonconductive material, vvheen Tic body is configured to receive the stein and the terminal port Witch a camp of Me body; an eIccrical connection plate attached to a bottom portion of the body; and a span" surrounding the stem of the contact pin, wherein the spring is disposed within the body such that an air gap exists between the electrical connection plate and the terminal point of the condo pin when the spnns is uncompressed.

   2. The electrical contact of claun 1, wherein hc contact head filrrher composing one or more legs 3. The electrical contact of claim 9, \vberem die contact head further comprising a foot on each of the one or more legs.

   0. The electncal contact of claim 2, wherein the coniacT head fisher comprising a bridging pomon, wherein We contact pin is disposed vithn Me bridging portion 5. The electrical contact of claim 1, wherein The contact pin funkier comprising one or more]areral projections.

   6. The electrical contact of claun 5, wherein Me one or more lacral projections of the contact pin are embedded withm the contact head 7. The clectncal contact of claim 1, wherein the spring is disposed berween a nod surface of body and the contact head.: - 14

   / 8 The electncal contact of claim 7, wherein The contact pin touches the electrical connection plate when Me spring is compressed by a force exerted on The top end of the conISc! pin.

   9 The electrical contact of claim 1, wherein the elecmcal coruecrion plate fiercer! composing one or more ears configured to attach the electrical connection plate To Me body.

   1). A base of an electronic device composing: an inTcmal clrcui; and an elecmcal contact comprising an electrical connection plate and a contact pin, wherein rbe e,cctncal connecnoD plate Is electrically connected TO the internal: circuit, wherein the contact pin is configured to move berween a first position and a j second position, wherein us the firs: position The conTec! pin is clecuically separated from tbe elecrrical connection plate by an air gap and in the second posiun the contact pin touches the electrical connection plate.

   11. The base of claim 8, wherem the electrical contact finisher composing a spring configured to maintain the contact pin in Tic first position when The spnng Is In an I uncompressed stare 1. The base of claim 8, wherein the elecmcal contact finisher comprising a spring configured to be compressed by a force exuded on a top end of the contact pin to move hit contact pin from We first position to the second position.

   13. The base of claim 8' wherein the elecmca] contact fiddler comprising one or more prongs. 14. The base of claim 13, Fierier comprising one or more side apertures configured to receive The one or more prongs of the electrical contact.

   15. A cordless telephone comprising.

   a handset having a contact point a' a bonom person of die handset; -

   ! a bees unit having an Infernal circus' configured To be elecTncally connected To He contact point when The handset is rested within a cradle cavity of The base unit; and an clecincal conucT attached TO The cradle cavity, The electrical ConTac composes a contact pin, a span", and an electrical Connection plate, The clecTncal connection place is eIcemcally connected TO the u:T-emal C3rCUiT of The base usul, The spring maintains an air gap between The contact pin and the clecmcal connection plate hcn the handse' is no: in the cradle cavlry, wherein when The handset is placed In die cradle cavity, the contact point Touches The contact pin and Me handset compresses The spun" SO ThaT The ConTacT pin Touches The electrical connection plate.

   16. Me cordless Telephone of clean 15, vhercn rho electrical contact further composing a contact head and a body.

   17. The cordless telephone of claim 16, whcTein The contact head and The body are made of a nonconductive maenl.

   18. The cordless telephone of claim 15, vhercn the contact pin is embedded within The contact head such ThaT a Top end of The contact pin Is exposed above The contact head to enable electrical cecuon bcwocn The condor pin of the elecncal contact and hc contact point of The handset I 9. The cordless Telephone of clown 18, wherein the contact pin further Includes a stem.

   20. The cordless tclephonc of claim 18, wherein the spnug surrounds She sign.

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