Search Images Maps Play YouTube News Gmail Drive More »
Sign in
Screen reader users: click this link for accessible mode. Accessible mode has the same essential features but works better with your reader.

Patents

  1. Advanced Patent Search
Publication numberUS3617660 A
Publication typeGrant
Publication dateNov 2, 1971
Filing dateJan 23, 1970
Priority dateJan 23, 1970
Also published asCA948247A1, DE2057373A1, DE2057373B2
Publication numberUS 3617660 A, US 3617660A, US-A-3617660, US3617660 A, US3617660A
InventorsKrakinowski Morris
Original AssigneeIbm
Export CitationBiBTeX, EndNote, RefMan
External Links: USPTO, USPTO Assignment, Espacenet
Keyboard actuating mechanism for diaphragm electric switch contact array
US 3617660 A
Abstract  available in
Images(6)
Previous page
Next page
Claims  available in
Description  (OCR text may contain errors)

United States Patent 3,120,583 2/1964 Cornell Inventor Morris Krakinowski Ossining, N.Y.

App]. No. 5,431

Filed Jan. 23, 1970 Patented Nov. 2,1971

Assignee International Business Machines Corporation Armonk, N.Y.

KEYBOARD ACTUATING MECHANISM FOR DIAPHRAGM ELECTRIC SWITCH CONTACT ARRAY 21 Claims, 19 Drawing Figs.

U.S. CI 200/1 R, 200/5 R, 200/46, 200/86, 200/159, 200/172 R Int. Cl. H0lh 9/00, H0lh 43/08, H0lh 3/12 Field 01' Search 200/1, 5,

References Cited UNITED STATES PATENTS 3,120,584 2/1964 Grunfelder et al ZOO/5 E 3,205,318 9/1965 Bilek 200/5 E 3,290,439 12/1966 Willcox et al 200/5 A X 3,308,253 3/1967 Krakinowski 200/46 3,350,518 10/1967 Krakinowski et a1. 200/46 3,382,338 5/1968 Arseneault et al 200/159 3,494,550 2/1970 Hayes et al. 235/145 3,472,974 10/1969 McGough 200/159 X Primary Examiner-l R. Scott AllomeysHanlfin and .lancin and Graham S. Jones, II

PATENTEDNUVZ l9?! 3.611660 SHEET 10F 5 INVENT MORRIS KRAKI Kl BYM/W ATTORNEY WWW ml 3.617.660

SHEET 20F e FIG. 3

TYPICAL FORCE-DEFLECTION CURVE OF ACTUATING MECHANISMS FORCE (GRAMS) l llll'l DEFL PRETRAVEL OVERTRAVEL' FIG. 4 ACTUATING FORCE ALONG KEY DIAMETER FORCE (GR AMS) CENTER LINE OF KEY QPMOGRAMS l 1 DEFL *30 -15 .15 .30 (mc gs) .025 .050 .075 (INCHES) PATENTEnuuvz |97l 3,617,660

SHEET am 6 PATENTEDNUH Ian 3,617,660

SHEETSOF 6 I FIG. 9B 20 KEYBOARD ACTUATING MECHANISM FOR DIAPHRAGM ELECTRIC SWITCH CONTACT ARRAY BACKGROUND OF THE INVENTION 1 Field of Invention This invention relates to keyboards for providing input of data to electrical apparatus and more particularly to such keyboards employing diaphragm switches and the like.

2. Description of Prior Art Diaphragm switches of the kind described in commonly assigned Krakinowski US. Pat. No. 3,308,253 have heretofore been included in keyboard designs as shown in Arsenault et al. US. Pat. No. 3,382,338, Hayes et al. United States patent application Ser. No. 609,216 filed Jan, 13, 1967 now US. Pat. No. 3,451,168 and Yarborough U. S.;Pat. application Ser. No. 767,755 filed Oct. 15,1968 now U.S. Pat. No. 3,517,149 which provide each key position vwith a separate keying mechanism, including a keying surface, an elastic coupling medium, and an actuator. Special devices must be incroporated to protect the switch fromoverload by the user.

An object of this invention is to provide an integrated keying mechanism sewing all keys in an array with common parts to reduce the number of parts, simplify the structure and simulate to the user the response of the mechanism to his operation thereof in terms of manual force and pressure required for operation, pretravel, overtravel, variable touch, and the effect of a key stop to that provided by; conventional keyboard operated apparatus such as typewriters.

Another object of this invention is to provide a simplified electrical keyboard incorporating nieans for protecting the contact mechanism from excessive force applied to the keying surface.

A further object of this invention is to provide an integrated keying mechanism including means for prevention of interaction between the keying mechanismv for one set of contacts and adjacent unrelated contacts.

Still another object of this invention is to enhance the uniformity of manual pressure required to achieve contact closure so that in the event of offcenter operator keying strokes on the keying surface of the keyboard closure will occur for a force equal to that required when the stroke is on center. 1

Another object ofthis invention is a keyboard capable of absorbing high impact blows upon the keying area without damage to the mechanism.

Further a keying mechanism with a bounceless actuator is desired, in order to minimize transmission of vibratory forces to the contacts.

SUMMARY or THE INVENTION In accordance with this invention, a keyboard apparatus is provided including meansfor keying in data, an actuator for actuating an array of switches, a plurality of diaphragm switches, and deformable means for coupling the actuator member and the switches.

Further in accordance with this invention, a plurality of elastomeric projections from" the actuator cooperate with the switches and means are included within the actuator member for stopping the actuator member after a predetermined degree of travel has occurred to minimize coupling of the stress pattern to adjacent projections;

Still another aspect of this invention relates to a separator frame and a plurality of keying padsl provided for alignment with the protrusions upon the actuator for desirable manual keying action.

In another aspect of this inventiomperipheral means about one or more protrusionsprovide means for supporting the actuator after a predetermined degree of displacement, and for spreading force applied over a substantially greater area.

The foregoing and other objects, features and advantages of the invention will be apparent from'the following more particular description of preferred embodiments of the invention, as illustrated in the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. .1 shows a vertical section of an integrated keyboard formed of an array of diaphragm switches with a single actuator member incorporating an array of protrusions thereon with a plurality of keys above the actuator.

FIG. 2 shows a top plan view of the keyboard shown in FIG. 1.

FIG. 3 shows a graph of force applied to a key as shown in FIGS. 1 and 2 as a function of displacement of the upper surface of the actuator sheet beneath that key.

FIG. 4 shows force required on a particular key as a function of lateral displacement from the center of the key along a key diameter.

FIG. 5A shows a vertical section of the actuator and diaphragm switch shown in FIGS. 1 and 2.

FIG. 5B is a bottom plan view taken along lines 58-55 in FIG. 5A showing the bottom of the actuator.

FIG. 6A is a vertical section of a modified actuator and switch including a plurality of contact positions per key.

FIG. 6B is a bottom view of the actuator-of FIG. 6A taken along line 6B6B.

FIG. 7A is a vertical section of a further modified actuator and switch for a square key with plural contacts taken along line 7A-7A in FIG. 78.

FIG. 7B is a bottom plan view taken along line 78-78 in FIG. 7A.

FIG. 7C is a vertical section of the embodiment of FIG. 7A at right angles to FIG. 7A taken along line 7C-7C in FIG. 7A.

FIG. 8 shows a vertical section of a further modified actuator and switch.

FIG. 9A shows a vertical section of a modified actuator and switch with a ring-shaped rib concentric with the central actuating protrusion in place of the peripheral protrusions.

FIG. 9B shows a bottom plan view taken along line 93-98 in FIG. 9A.

FIG. 10A shows a vertical section of a modified actuator and switch with a hollow about the central actuating protrusion and an elevated surface between hollows.

FIG. 108 shows a bottom plan view taken along line 10B- 108 in FIG. 10A.

FIG. 11 is a vertical section of a rigid actuating protrusion projected to actuate a diaphragm switch.

FIG. 12 is a vertical section of a sharp edged rigid actuator projected to actuate a diaphragm switch.

FIG. 13 is a vertical section of another smaller cross section sharp edged actuator projected to actuate a diaphragm switch.

DESCRIPTION OF THE PREFERRED EMBODIMENTS elastomer nomenclature sheet 10 preferably about 0.010 inch to 0.03 inch thick with indicia bearing keys 11 about 5/8 inch in diameter to be manually operated. The nomenclature sheet 10 defines visual keying areas 11. The polyurethane elastomer is preferred because it is tough, wears well and allows for large localized deformation without affecting adjacent keying positions. The nomenclature sheet 10 is part of the keying mechanism designed to be freely removable, at will, for replacement by another such unit bearing different indicia so that the keyboard can be used for a multiplicity of purposes. In addition, unlike overlays, the indicia and the keys are replaceable, allowing the indicia to be printed directly on the key where keying mechanisms are interchanged.

Below the sheet 10 is a protective sheet 14 (0005-0010 inch thick of elastomer) serving as a dust cover sealing the actuating mechanism below from the environment and facilitating manipulation of the sheet 10.

Under protective sheet 14 is a rigid frame member 15, preferably of aluminum, having circular (or square) holes 17 therein aligned concentrically with keys 11 to permit keys 11 to be depressed therethrough, which in combination with keys 11 and buttons 16 defines tactile keying areas corresponding to the visual keying areas 11.

Extending through circular holes 17 are key buttons 16 formed of a very soft elastomer molded integrally in a pad 18. The elastomer is preferably composed of a closed-pore cellular neoprene rubber (one-eighth inch-one-quarter inch thick) with a low compressive modulus on the order of ASTM SC-Ol I013.

Below the pad 18 is an actuator sheet 20 comprised of a molded preferably neoprene rubber or elastomer having a medium hardness of about 55-65 durometer about one-sixteenth inch thick having a plurality of clusters of truncated cone-shaped protrusions 21, 22 with one protrusion 21 in the center and four preferably slightly. shorter protrusions 22 spaced thereabout as shown in FIGS. A and 5B. Each protrusion 21 is aligned with the centers of keys 11, holes 17 and key buttons 16. The outer protrusions 22 are in a circle about as inch diameter spaced about the central protrusion 21. Preferably the central protrusion 21 is about 6 to mils longer than one-eighth inch and the other protrusions are /1:- inch long. Protrusions 21 when depressed move contacts 24 into contact with contacts 27 of switches 28 which are elastic diaphragm switches described next, herein.

Below the actuator 20 is an array of diaphragm switches including diaphragm 23 of elastic material, preferably Mylar polyester, which is 0.002 to 0.003 inch thick, and is copper clad (with gold plating) 0.0014 inch thick to form contacts 26 and connections thereto, the the contacts 24 below protrusions 21. Below diaphragm 23 is a Mylar separator sheet 25 preferably 0.003 inch thick having a plurality of holes 26 therein 5/32 inch in diameter aligned coaxially with protrusions 21. Diaphragm 23 is spaced from spacer 25 and sheet 30 is spaced therefrom by the copper members 24 and 27 which extend beyond the holes 26 on either side thereof as shown in FIG. 7C and which are sufficiently stiff to hold the diaphragm above holes 26 when control protrusions 21 are not depressed. Below separator sheet 25 is sheet 30 on a base 29 of molded plastic bearing contacts 27 which are copper clad with gold plate 0.00 l 4 inch thick.

The combination of the very soft key pads 16 and the actuator sheet 20 of medium hardness rubber provide a relatively long keying stoke with pretravel and overtravel, as shown in FIG. 3. The soft buttons 16 and the flexible keys 11 provide a combination of actuating elements with a low spring constant,

and long stroke, which depends upon the stiffness of buttons 16 and keys 11. An efficient method of adjusting the forcedeflection characteristics or the feel" of the keying mechanism to requirements is to vary the gap between the sheet 14 and buttons 16 so a selected key 11 must deflect before any force is transmitted down to the associated switch. Another method is to vary the ratio of stiffnesses between actuator 20 and pad 18, by geometry or by changing the stiffness of the material.

The actuator sheet 20 with the discrete projections 21, 22 concentrates the actuating force on the switches 28. This arrangement permits relatively large keying areas for each key position. The keying area can be %-inch diameter for a switch area of only one-eighth inch to one-fourth inch. The actuating force required to operate a switch is-essentially constant over the surface of a keying area as illustrated by FIG. 4, based upon a specific switch which was tested which does not necessarily show the general variation but simply is illustrative. However, because of projections 22, the actuating force remains constant over the surface of each of the keys 11. As indicated in FIG. 5A, and FIG. 5B, the cluster of protrusions 21,22 is well within the projected cylinder defined by the keys 1]. The peripheral protrusions 22 are slightly shorter than the central protrusion 21 which actuates its switch. These protrusions 22 serve as key stops so that the actuator sheet 20 and projection 21 can be stopped from excessive depression below the level necessary to close contacts 24 and 26, so that force can be spread out to protect the switches 28, and so that the adjacent protrusions 21 will be prevented from closing their switches by general lowering of actuator 20 in the areas surrounding the associated button 16. The protrusions 22 will tend to act as a fulcrum causing areas outside the ring" of a cluster to rise rather than fall. Since protrusions 22 are shorter, they facilitate closure by the central protrusion 21.

As force is applied, it is distributed as desired, and until protrusions 22 contact the switch 20, force is concentrated on actuators 21. However, as forces are increased, the forces are spread out onto stops 22 so that the greater forces are distributed over a relatively larger area of sheet 23 and switch 28 by stops 22.

FIG. 3 shows the action of the keying mechanism as the force applied on the vertical axis versus the displacement of the top surface of actuator 20 with pretravel, (prior to closure, and overtravel after closure). At the end of the flat portion of the curve (after the switching point) the rise reflects the load redistribution that occurs.

When the actuator protrusion 21 is depressed upon diaphragm 23, the protrusion 21 must be sufficiently deformable and visco-elastic so that it will produce minimal extrusion of the copper and the diaphragm 23 and will permit very long diaphragm life. The hole 26 is large enough in diameter so that an overall clearance between the protrusion 21 and the edge of the hole 26 keeps the deflection stress on the copper and the deflected diaphragm below a critical value.

FIGS. 6A and 6B show a vertical section and a bottom plan view of a modified actuator sheet 20 with a larger cluster of protrusions with five central protrusions 21 and eight peripheral protrusions 22 for operating five sets of contacts in diaphragm switch unit 28. This arrangement is desirable for larger keying areas, or where it is desired to assure even a more uniform degree of equality of actuating force required to close at least one set of contacts to be applied over the area of a key 11.

FIG. 7A shows a vertical section along lines 7A-7A in FIG. 7B and FIG. 7B shows a bottom plan view of a modified arrangement of the actuator sheet 20 which is suitable for use in a similar keyboard with square keys. Instead of peripheral protrusions, however, a stop is formed by a rib 32 inside the area of a key 33 shown in phantom, with the central protrusions 21 arranged as shown to fill the area inside rib 32. The rib 32 serves as a stop which prevents actuation of or by adjacent key areas and which absorbs overtravel forces as described above.

FIG. 7C shows a vertical section along line 7C-7C in FIG. 7A which shows how contacts 24 and 27 bear against separator 25 to maintain separation of the diaphragm 23, separator 25 and sheet 30.

FIG. 8 shows a further modified version of the actuator sheet 20 with the stops 34 formed integrally with the central protrusions 21, so that overtravel will not pull down adjacent protrusions 21, because stops 34 will prevent further depression of the actuator 21 then operating the contact which is then switching from deflecting sheet 20 materially, and whereby stops 34 absorb and spread overtravel forces to protect the switch.

FIG. 9A shows a vertical section and FIG. 9B shows a bottom plan view of an actuator sheet 20 having central protrusions 21 surrounded by individual peripheral protrusions 35 analogous to a large number of protrusions 22 merging together at a predetermined radius.

In FIGS. 10A and B, the radial rib 35 of FIG. 9 is replaced by a solid stop 36 between depressed areas 37 surrounding the central protrusions 21', whereby the protrusions are located in craterlike recesses in the lower surface of the actuator member 20.

FIG. 11 shows a hypothetical rigid member 40 which is not elastomeric, which is employed to depress the diaphragm 23, and it is shown at 41 that the copper 24 and the diaphragm 23 have been deformed. In a relatively short time, the copper will be permanently extruded or bent by such an actuator.

FIG. 12 shows a hypothetical rigid square actuator 42 with square corners 43 which would tend to tear the diaphragm '23 at corners 43, although it is wide enough to not deform electrode 23. f

In FIG. 13, a third hypothetical ri'gid actuator 45 is shown with a flat lower surface 46 and edges 47 designed so that if it were perfectly aligned with the diaphragm 23 and the contact 24 that it would provide an even enough force on contact 24 to avoid deformation of the contact 24. However, in fact, in a mechanism with dozens of actuators, the probability of maintaining all actuators 45 in perfect alignment is exceedingly low; and furthermore, it is even lower that perfect alignment would persist. Thus, in short order, at least some of the switch contacts 24 would as in FIG. 13 be bent by a corner 47 at an angle which is exaggerated in FIG. 13, for convenience of illustration, to show the bending of contact 24 to provide a poor set of contacts.

What is claimed is:

1. An apparatus for actuating a diaphragm switch device comprising:

a keyboard; Q

a diaphragm switch device including an array of opposed electrical contacts, one of said contacts in each pair being connected to a diaphragm,

a deformable member carryingaplurality of deformable projections, said deformable member confronting said diaphragm on the side opposite .to said one of said contacts, with at least some of said projections facing said diaphragm and being aligned to cooperate with said switch device to close contacts, when actuated,

said keyboard cooperating with said deformable member to permit selective, actuation of sets of contacts of said switchby depressing a segment of said keyboard.

2. An apparatus for actuating a diaphragm switch comprisa diaphragm switch device including an array of opposed electrical contacts, one of said contacts in each pair being connected to a diaphragm, I

a deformable member carrying afplurality of deformable projections, said deformable member confronting said diaphragm on the side oppositeto said one of said contacts, with at least some of said projections facing said diaphragm and being aligned to cooperate with said switch device to close contacts, when actuated,

said keyboard cooperating with said deformable member to permit selective actuation of sets of contacts of said switch by depressing a segment ofsaid keyboard,

a keyboard,

a rigid frame member below saidkeyboard including key position separator openings therethrough,

soft button means coupling said keyboard through said separator openings to said deformable member.

3. Means for actuating an array of diaphragm switch contacts comprising:

keyboard means, including a plurality of separate keying areas for operating separate sets of contacts of a said diaphragm switch,

an elastomeric sheet bearing upon the lower surface thereof a plurality of projections adapted for registration with said contacts, said projections being aligned with said keying areas for selective actuation actuation of contacts associated therewith,

said projections being surroundedv by means integral with said sheet and not in registration with said contacts for resisting depression of said projections beyond a selected distance.

4. Means for actuating an array of diaphragm switch contacts comprising:

an elastomeric sheet bearing upon the lower surface thereof a plurality of projections adapted for registration with said contacts.

said projections being surrounded by means for resisting depression of said projections beyond a selected distance, rigid frame means having openings therethrough,

indicia bearing key means, aligned with said openings,

formed on a top surface member for said array above said frame means,

soft elastomeric button means disposed between said indicia bearing key means and said elastomeric sheet extending through said openings in said rigid frame means.

5. Manual data input apparatus comprising:

a manual keying surface,

an elastic diaphragm switch array,

actuator means composed of deformable material for coupling said keying surface to a switch to be actuated in said array through defonnable means, andsaid actuator means including deformable means for restraining motion of a key area of said actuator beyond a predetermined displacement.

6. Manual data input apparatus comprising:

a manual keying surface,

an elastic diaphragm switch array,

an actuator means composed of deformable material for transmitting force from said keying surface to an individual switch to be actuated in said array through resilient deformable means, and said actuator means including deformable means for reacting to displacement thereof in excess of a predetermined displacement required to close said switch effective as a stop for said actuator means, effective for inhibiting further deflection and effective for inhibiting actuation of adjacent switches by materially limiting displacement of said actuator means at positions remote from a said switch to be actuated. 7. A keyboard, for data entry including as follows: a keyboard, an actuator member comprising a sheet including an input surface and an output surface on opposite sides thereof,

an array of means for switching comprising a plurality of diaphragm switches each having an actuation surface confronting said output surface of said actuator member,

said actuator member having a plurality of projections extending therefrom to contact said actuation surface with said projections being in alignment with said switches, and

said keyboard cooperating with said actuator member to permit selective actuation of each of said switches by depressing a segment of said keyboard.

8. A keyboard for data entry including as follows:

elastomeric keyboard means for bearing indicia,

an actuator member basically comprising an elastomeric sheet including an input surface and an output surface on opposite sides thereof,

said keyboard means overlying said actuator member,

an array of means for switching comprising a plurality of elastic diaphragm switches each having an actuation surface confronting said output surface of said actuator member,

said actuator member having a plurality of projections extending therefrom to contact said actuation surface with projections in alignment with the input member of one of said switches for cooperation therewith to respond to deflection of said actuation member in a specific area to provide closure of contacts of a switch in said specific keyboard area,

and stop means included in said actuator member operative for restraining deflection of said actuator beyond a predetermined distance.

9. Apparatus in accordance with claim 8 wherein said means for stopping comprises a plurality of additional projections.

10. Apparatus in accordance with claim 9 wherein said additional projections are shorter than said first named projec- 5 tions.

11. Apparatus in accordance with claim 10 wherein a rigid frame with key holes is disposed between said keyboard means and said actuator member to provide separation.

12. Apparatus in accordance with claim 11 wherein a plurality of soft elastomeric pads couple said keyboard means and said actuator member through said key holes.

13. A device operable selectively for closing pairs of contacts of an array of contacts comprising, in combination:

an array of pairs of electric contacts wherein a movable contact of each said pair is carried on an elastic sheet and is separated from the opposing contact of the respective pair by a spacer having an opening therethrough in alignment with and larger than said pair of opposing contacts;

a deformable operator memberoverlying said elastic sheet and having on the side adjacent said elastic sheet an array of operating elastomer nibs of a given length, one in alignment with each of said contacts on said elastic sheet and adapted when depressed to move the respectively aligned contact on said sheet into contact with its opposing contact;

said operating member having arranged around each said nib a plurality of additional elastomer nibs of a length shorter than said given length, and spaced from said nib to be beyond the edges of said aligned opening in said spacer;

said deformable operator member having on its opposite side an elastomer operating area larger than and in alignment with each said elastomer nib of said given length, each said area being separated from adjacent areas by a trough area.

14. The device of claim 13 having a rigid frame member in said trough areas.

15. The device of claim 14 having an elastomer indicia bearing member overlaying said deformable operator member and said rigid frame and having an indicia area in alignment with each said operating area of said deformable operator.

16. A device operable selectively for closing pairs of contacts of an array of contacts comprising, in combination:

an array of pairs of electric contacts wherein a movable contact of each said pair is carried on an elastic sheet and is separated from the opposing contact of the respective pair by a spacer having an opening therethrough in alignment with and larger than said pair of opposing contacts;

a deformable operator member overlying said elastic sheet and having on the side adjacent said elastic sheet an array of operating elastomer nibs ofa given length, one in alignment with each of said contacts on said elastic sheet and adapted when depressed to move the respectively aligned contact on said sheet into contact with its opposing contact;

said operating member having an arrangement of additional elastomer nibs of a length shorter than said given length arranged to surround groups of at least one of said operating nib and spaced from said surrounded group of nibs a distance whereby said additional nibs are ineffective to close contacts associated with said surrounded group of nibs;

said deformable operator member having on its opposite side an elastomer operating area in alignment with each said group of surrounded nibs, each said area being separated from adjacent areas by a trough area.

17. The device of claim 16 having a rigid frame member in said trough areas.

18. The device of claim 17 having an elastomer indicia bearing member overlying said deformable operator member and said rigid frame and having an indicia area in alignment with each said operating area of said deformable operator.

19. A device operable selectively for closing pairs of contacts of an array of contacts comprising, in combination:

an elastic diaphragm switch comprising an array of pairs of electric contacts;

a deformable operator member overlying said switch array and having on the side adjacent said switch array, an array of operating elastomer nibs of a given length, one in alignment with each of said pairs of contacts on said switch array and adapted when depressed to close the respective pair of contacts;

said operating member having arranged around each said nib, a plurality of additional elastomer nibs of a length shorter than said given length and spaced from said nib a distance whereby said additional nibs are ineffective to close said contacts;

said deformable operator member having on its opposite side an elastomer operating area larger than and in alignment with each said elastomer nib of said given length, each said area being separated from adjacent areas by a trough area.

20. The device of claim 19 having a rigid frame member in said trough areas.

21. The device of claim 20 having an elastomer indicia bearing member overlaying said deformable operator member and said rigid frame and having an indicia area in alignment with each said operating area of said deformable operator.

Patent Citations
Cited PatentFiling datePublication dateApplicantTitle
US3120583 *Jul 1, 1960Feb 4, 1964Teaching Machines IncMultiple switch device for selectively interconnecting multiple electrical conductors
US3120584 *Nov 29, 1960Feb 4, 1964Western Electric CoMultisurface cross point switching mechanisms
US3205318 *Jun 11, 1963Sep 7, 1965IttWire spring pushbutton assembly
US3290439 *Apr 29, 1963Dec 6, 1966WillcoxData encoding keyboard
US3308253 *Mar 25, 1965Mar 7, 1967IbmDiaphragm switch having a diaphragm supported on an incompressible layer and an elastomer overlaying the diaphragm
US3350518 *Feb 11, 1966Oct 31, 1967IbmReader for punched record
US3382338 *Apr 26, 1966May 7, 1968IbmPushbutton actuator for elastomeric switch
US3472974 *Sep 25, 1967Oct 14, 1969Automatic Elect LabPushbutton switch activated by a slide with a plurality of toggle joints and cams
US3494550 *Jan 13, 1967Feb 10, 1970IbmUniversal keyboard
Referenced by
Citing PatentFiling datePublication dateApplicantTitle
US3681723 *Dec 9, 1971Aug 1, 1972Western Electric CoMagnetic membrane switch
US3723673 *Oct 13, 1971Mar 27, 1973Addmaster CorpKeyboard switch assembly with wire conductor matrix contact array
US3725907 *Jun 1, 1971Apr 3, 1973Texas Instruments IncPushbutton keyboard system
US3743798 *Sep 13, 1971Jul 3, 1973North American RockwellElongated spring coil conductors applying tension force to pushbutton actuators in keyboard matrix switch assembly
US3811025 *May 17, 1973May 14, 1974Lockheed Electronics CoTouch panel switch assembly
US3858202 *Apr 2, 1973Dec 31, 1974Texas Instruments IncPushbutton keyboard system
US3911234 *Jun 25, 1974Oct 7, 1975Amp IncKeyboard type switch assembly having fixed and movable contacts disposed on foldable flexible printed circuit board
US3930083 *Jul 26, 1974Dec 30, 1975Litton Systems IncKeyboard panel for an electric switch contact
US4022993 *Jun 9, 1975May 10, 1977Litton Systems, Inc.Switch assembly having electrically illuminated character display devices between transparent actuators and switch arrays
US4029915 *Dec 3, 1975Jun 14, 1977Hoshidenkoseizo Kabushiki KaishaMiniaturized calculator keyboard switch assembly having universally pivoted key actuators
US4046975 *Sep 22, 1975Sep 6, 1977Chomerics, Inc.Keyboard switch assembly having internal gas passages preformed in spacer member
US4066850 *Jun 4, 1976Jan 3, 1978Ncr CorporationKeyboard switch assembly having interchangeable cover plate, indicating layer and actuator switch assembly in any operative combination
US4071718 *Oct 22, 1976Jan 31, 1978Bowmar Instrument CorporationFlat keyboard assembly having cover type membrane with protrusions to align switch components
US4207443 *Aug 9, 1978Jun 10, 1980Mikado Precision Industries Ltd.Key-operated switch and an assemblage of such switches for electronic desk calculators or the like
US4237358 *May 7, 1979Dec 2, 1980Oak Industries Inc.Isolation membrane switch
US4258096 *Nov 9, 1978Mar 24, 1981Sheldahl, Inc.Composite top membrane for flat panel switch arrays
US4271333 *Sep 25, 1979Jun 2, 1981Northern Telecom, Inc.Pushbutton dial assembly
US4349712 *Jan 21, 1980Sep 14, 1982Itt Industries, Inc.Push-button switch
US4491702 *May 3, 1982Jan 1, 1985Sun Arrow Koeki Company Ltd.Key-top panel and keyboard structure using the panel
US5132496 *Apr 5, 1991Jul 21, 1992Acer Inc.Membrane switch
US5193669 *Feb 28, 1991Mar 16, 1993Lucas Industries, Inc.Switch assembly
US5199557 *Nov 19, 1990Apr 6, 1993Mec A/SMethod of producing an electric or electronic component, a method of producing a key and a key
US5349263 *Oct 6, 1992Sep 20, 1994Mitsumi Electric Co., Ltd.Pointing device suitable for miniaturization
US5401922 *Apr 25, 1994Mar 28, 1995Illinois Tool Works Inc.Membrane switch
US5579002 *Jun 7, 1995Nov 26, 1996Arthur D. Little Enterprises, Inc.User-configurable control device
US5729222 *Nov 25, 1996Mar 17, 1998Jerry IgguldenUser-configurable control device
US5986221 *Dec 18, 1997Nov 16, 1999Automotive Systems Laboratory, Inc.Membrane seat weight sensor
US6999009Aug 27, 2002Feb 14, 2006Logitech Europe S.A.Sensing keys for keyboard
EP0444914A2 *Feb 27, 1991Sep 4, 1991Lucas Industries Public Limited CompanySwitch assembly