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Publication numberUS3789167 A
Publication typeGrant
Publication dateJan 29, 1974
Filing dateDec 20, 1972
Priority dateDec 20, 1972
Publication numberUS 3789167 A, US 3789167A, US-A-3789167, US3789167 A, US3789167A
InventorsCoulter J, Seeger R
Original AssigneeChomerics Inc
Export CitationBiBTeX, EndNote, RefMan
External Links: USPTO, USPTO Assignment, Espacenet
Multi-output level keyboard switch assembly with improved operator and contact structure
US 3789167 A
Abstract
A structure which includes a circuit board having a conductive pattern thereon and supporting a resilient conductive layer by way of an insulator layer having a plurality of windows therethrough in alignment with portions of the conductive pattern, the resilient layer divided into at least two sections held electrically apart by pins coupled to a frame member in which the board and layers are packaged.
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Description  (OCR text may contain errors)

United States Patent [191 Seeger, Jr. et a1.

[ MULTI-OUTPUT LEVEL KEYBOARD SWITCH ASSEMBLY WITH IMPROVED OPERATOR AND CONTACT STRUCTURE [75] Inventors: Richard E. Seeger, Jr., Topsfield;

John G. Coulter, Reading, both of [21] Appl. No.: 316,656

1 Jan. 29, 1974 12/1972 Seeger, Jr. et a1. 200/5 A 3,721,778

3/1973 Seeger, Jr. et al. 200/159 B Primary ExaminerJ. R. Scott 5 7] ABSTRACT A structure which includes a circuit board having a conductive pattern thereon and supporting a resilient [52] us 200/5 200/159 200/166 C conductive layer by way of an insulator layerhaving a [51] [11L Cl. H0111 13/52 plurality of windows therethrough in alignment i [58] of SearchZOO/ 1 5 5 16 A, 159 portions of the conductive pattern, the resilient layer 200/166 C divided into at least two sections held electrically apart by pins coupled to a frame member in which the [56] References Cted board and layers are packaged.

UNITED STATES PATENTS 3,699,294 10/1972 Sudduth 200/159 B X 6 Claims, 4 Drawing Figures l0 I2 I50 l4 CONDUCTIVE PLASTIC I60 I 6b V Il' I ,3 Am ,n\\i\\ PATENTEDJANZSIBM 3.789'167 FIG'4 MULTI-OUTPUT LEVEL KEYBOARD SWITCH ASSEMBLY WITH IMPROVED OPERATOR AND CONTACT STRUCTURE STATEMENT OF THE DISCLOSURE keyboard structure which is constructed to provide more than one output voltage level.

This invention is an improvement over the keyboard structure shown copending in U.S. Pat. application Ser. No. 154,752 filed June 12, 1971 by Richard E. Seeger,.lr., and William J. Lynn now U.S. Pat. No. 3,721,778.

In the past i.e., as disclosed in the aforementioned application, each of the keyboard output terminals provided the same output voltage level to represent respective key depression or switch closure. This was quite adequate as long as a single output level was all that was needed to drive digital logic circuitry or the like. But as time went on there grew the need for a keyboard to supply not only the signals for logic circuits but also some signals at much higher voltage levels to control operative or analog devices such as a servomechanism.

While there are undoubtedly many ways of converting one voltage level to another voltage level using circuitry, this would have been quite expensive. Accordingly, there developed a need for the above to be accomplished using the basics of the keyboard structure shown in the above mentioned application without substantially raising the cost of keyboard construction. The present invention accomplishes the above multiple voltage level output requirement in a novel manner while using the basics of the prior keyboard structure with a minimum of costly modifications.

BRIEF DESCRIPTION OF THE DISCLOSURE The keyboard of the present invention provides mul tiple voltage level outputs from different terminals thereof by using a multi-segrnent conductive layer or pad positioned on an insulator layer having a plurality of windows therethrough in alignment with portions of a conductive pattern, the segments of the conductive layer being electrically separated from each other by retaining means and in the preferred embodiment being coupled to different input or supply signal terminals. Key or switch-like members of the keyboard are depressible to force the conductive segments through selected ones of the windows of the insulator layer against portions of the conductive pattern in order to provide output signalsat keyboard output terminals coupled to different portions of the conductive pattern.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a top view of a keyboard of the present invention;

FIG. 2 is a bottom view with the parts cut away of the keyboard;

FIG. 3 is a sectional view broken'at the center and taken along line 3-3 of FIG. 1; and

FIG. 4 is a sectional view taken along line 44 of FIG. 2.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT Reference should now be had to FIGS. 1 to 4 for a description of the preferred embodiment of the disclosure.

The keyboard comprises a frame 10 preferably of insulator material more preferably of plastic such as A.B.S a high impact polystyrene or may be constructed of other type plastics such as polypropylene. The frame is provided with a plurality of divider members 11 which form thewalls of windows 12 extending through frame.

The underside of the divider members 12 includes a plurality of rods 13 (preferably formed at the same time as the frame i.e., by molding [see FIG.2]) which extend downwardly as shown in FIG. 4. The rods 13 are preferably of the same plastic material as the frame 10 and preferably may be softened by heat to form the head 13a to hold the keyboard assembly together as shown in FIG. 4. Alternatively the rods may be threaded and nuts may then be used to hold the keyboard assembly together.

Positioned directly below the frame member 11 is a thin plastic insulator layer 14 e.g., of Mylar which has indicia applied thereto. The indicia may be marked thereon using inks or may be applied thereto using other conventional techniques.

The layer 14 is provided with a plurality of holes 14a through which the rods 13 extend to locate it within the confines of the frame.

Positioned directly below the layer 14 is a conductive plastic layer 15 which is divided into at least two segments 15a and 15b. The conductive layer is preferably of a resilient material such as plastic e.g., silicone rubber filled with 10 to percent by volume of silver flakes. Rubber is defined as a plastic for the purposes of this invention.

The segments 15a and 15b are electrically isolated from each other, lie in substantially the same plane, and are preferably held isolated by at least two of the rods 13 extending through holes l5aa formed in each of the segments 15a and 15b. 1

Reference may be had to U.S. Pat'Nos. 3, 140, 342 and 3, 576, 387 for a description of othermaterial compositions suitable for use as the layer comprising segments 15a and 15b.

The segments 15a and 15b are positioned over an insulator plastic layer 16 e.g., of Mylar having a plurality of windows extending therethrough in line with windows 12. The rods 13 also extend through holes 16b in layer 16 to locate the layer 16 within the frame 10.

Below the layer .16 is a typical circuit board 17 tag, of Bakelite having a plurality of conductive electrical v contacts or pathways 18 formed thereon. See the aforementioned application for typical circuit patterns or pathways.

The circuit pattern may be formed conventionally from copper which is etched or by the spraying of conductive paint.

The electrical pathways are at least in part aligned with the windows so that the application of a presence (by a finger) to the force applying layer 14 can push portions of the conductive layer segments through the Windows 160 against the pathways 18. In this manner electrical contact is made between the conductive segments and the pathways 18. When the force is withdrawn, the resiliency of the conductive layer causes it to withdraw and spring back from the conductive layer and break contact. The rods 13 extend through holes 170 in the board to hold the assembly together.

In order to make electrical contact with the conductive segments 15a and 15b as well as the pathways 18, there are provided pins -30 supported in connector supports 20a-23a mounted to the board 17.

Electrical conductor pins 20 and 23 are electrically coupled directly to segments 15a and 15b respectively so that different input voltage levels may be applied to the segments e.g., 6v to pin 23 and segment 15b and 30v to pin 20 and segment 15a. The pins 20 and 23 are preferably embedded in the segments 15a and 15b and extend through holes 16b formed in the layer 16.

Electrical contact is made to the pathways 18 via pins 21 and 22 as shown. The left side of FIG. 3 represents the keyboard under the indicia marking X and the right side of FIG. 3 represents the keyboard under the indicia marking O with the parts below the other indicia broken away.

What is claimed 1. In a keyboard or the like which includes an insulator board having circuit pathways thereon, insulator means having a plurality of windows therethrough in alignment with selected portions of said pathways, a resilient electrically conductive layer means positioned on said insulator and divided into at least two segments that are spaced apart and electrically isolated from each other and lie in part in substantially the same plane, each of said segments covering at least one of said windows of said insulator layer, first means for pcsitioning and holding said segments in electrical isolation from each other, second means for applying force to push portions of said segments through said windows they overlie in order to make contact with said pathways, third means for providing electrical input signals to generate output signals represent of a force applied to said segments, a plurality of electrical signal output pins coupled to different ones of said pathways and in which the third means comprises electrical signal input pins, a different one of which is electrically coupled to each of said segments. 4

2. In a keyboard as called for in claim 1 in 'which said first means comprises a frame which has a plurality of rods extending therefrom, at least two of said rods extending through each of said segments to locate said segments with respect to each other.

3. In a keyboard according to claim 2 in which said rods extend through each of said layers and board to make a sandwich thereof.

4. In a keyboard according to claim 3 in which said frame is formed with a plurality of divider members de-- fining windows in at least partial alignment with said windows of said insulator layer and in which said second means comprises an indicia layer of insulator material positioned between said frame and said segments, said indicia layer having a plurality of markings thereon which may be seen through said windows in said frame.

5. In a keyboard or the like comprising electrical conductive layer means divided into at least two segments electrically isolated from each other,

a plurality of electrical pathways isolated from each other,

means for retaining said segments electrically isolated from each other, insulator means for maintaining said segments electrically isolated from said electrical pathways and having windows in alignment to permit selected portions of said electrical pathways to make electrical contact with each of said segments, means for relatively moving said segments and said pathways with respect to each other in order for selected segments to make electrical contact with selected pathways through said windows, and first electrical signal pins, a different one of which is electrically coupled to each of said segments.

6. In a keyboard according to claim 5 in which second electrical signal pins are coupled to different ones of said pathways.

Patent Citations
Cited PatentFiling datePublication dateApplicantTitle
US3699294 *May 18, 1971Oct 17, 1972Flex Key CorpKeyboard, digital coding, switch for digital logic, and low power detector switches
US3705276 *May 20, 1971Dec 5, 1972Chomerics IncKeyboard switch assembly with conductive plastic contactor and actuator spring sleeve biasing means
US3721778 *Jun 21, 1971Mar 20, 1973Chomerics IncKeyboard switch assembly with improved operator and contact structure
Referenced by
Citing PatentFiling datePublication dateApplicantTitle
US3862381 *Oct 29, 1973Jan 21, 1975Chomerics IncKeyboard switch assembly with multilayer, coextensive contactor means
US3930083 *Jul 26, 1974Dec 30, 1975Litton Systems IncKeyboard panel for an electric switch contact
US3973099 *Nov 11, 1974Aug 3, 1976American Micro-Systems, Inc.Push button switch for electronic watch
US4071718 *Oct 22, 1976Jan 31, 1978Bowmar Instrument CorporationFlat keyboard assembly having cover type membrane with protrusions to align switch components
US4128744 *Feb 22, 1977Dec 5, 1978Chomerics, Inc.Keyboard with concave and convex domes
US4145584 *Apr 25, 1977Mar 20, 1979Otterlei Jon LFlexible keyboard switch with integral spacer protrusions
US4158115 *Jun 26, 1978Jun 12, 1979W. H. Brady Co.Internally connecting flexible switch
US4194099 *Oct 25, 1977Mar 18, 1980W. H. Brady Co.Control panel overlay
US4243861 *Nov 20, 1978Jan 6, 1981The Cornelius CompanyTouch switch and contactor therefor
US4250495 *Nov 16, 1979Feb 10, 1981The Singer CompanyTouch sensitive control panel and a method of manufacture thereof
US4258096 *Nov 9, 1978Mar 24, 1981Sheldahl, Inc.Composite top membrane for flat panel switch arrays
US4368369 *Mar 5, 1981Jan 11, 1983Citizen Watch Co., Ltd.Electrical switch
US4390758 *Jan 16, 1981Jun 28, 1983Hendrickson Max SKey-actuated electrical lock
US4440999 *Aug 13, 1982Apr 3, 1984Press On, Inc.Membrane switch
US4441097 *Nov 20, 1981Apr 3, 1984Antroy Enterprises, Inc.Device for controlling a circuit
US4471177 *Aug 13, 1982Sep 11, 1984Press On, Inc.Enlarged switch area membrane switch and method
US5510783 *Jul 13, 1992Apr 23, 1996Interlink Electronics, Inc.Adaptive keypad
US7507923Dec 1, 2006Mar 24, 2009Omron Dualtec Automotive Electronics Inc.Electrical switch
US7982718 *Dec 29, 2006Jul 19, 2011Lg Electronics Inc.Mobile terminal with back-lighted directional keys
US8049728 *Dec 29, 2006Nov 1, 2011Lg Electronics Inc.Touch key assembly for a mobile terminal
Classifications
U.S. Classification200/5.00A, 200/512, 200/292
International ClassificationH01H13/702, H01H13/70
Cooperative ClassificationH01H2239/044, H01H13/702, H01H2229/044, H01H2223/034, H01H2207/012, H01H2229/026, H01H2209/078
European ClassificationH01H13/702
Legal Events
DateCodeEventDescription
Feb 8, 1990ASAssignment
Owner name: AMP KEYBOARD TECHNOLOGIES, INC., A WHOLLY OWNED SU
Free format text: ASSIGNMENT OF ASSIGNORS INTEREST.;ASSIGNOR:AMP INCORPORATED;REEL/FRAME:005258/0518
Effective date: 19890418
Owner name: LUCAS DURALITH AKT CORPORATION
Free format text: CHANGE OF NAME;ASSIGNOR:AMP KEYBOARD TECHNOLOGIES INC.;REEL/FRAME:005258/0527
Effective date: 19890428
May 21, 1981AS02Assignment of assignor's interest
Owner name: AMP INCORPORATED, HARRISBURG, PA., 17105, A CORP.
Owner name: CHOMERICS, INC.
Effective date: 19810511
May 21, 1981ASAssignment
Owner name: AMP INCORPORATED, HARRISBURG, PA., 17105, A CORP.
Free format text: ASSIGNMENT OF ASSIGNORS INTEREST.;ASSIGNOR:CHOMERICS, INC.;REEL/FRAME:003854/0523
Effective date: 19810511