US3693775A - Actuator for elastic diaphragm switch keyboard - Google Patents

Actuator for elastic diaphragm switch keyboard Download PDF

Info

Publication number
US3693775A
US3693775A US51284A US3693775DA US3693775A US 3693775 A US3693775 A US 3693775A US 51284 A US51284 A US 51284A US 3693775D A US3693775D A US 3693775DA US 3693775 A US3693775 A US 3693775A
Authority
US
United States
Prior art keywords
sheet
keyboard
elastomeric
projections
actuator
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
Application number
US51284A
Other languages
English (en)
Inventor
Kenneth A Brooks
Lawrence L Johnson
James A Mathewson
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.)
International Business Machines Corp
Original Assignee
International Business Machines Corp
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by International Business Machines Corp filed Critical International Business Machines Corp
Application granted granted Critical
Publication of US3693775A publication Critical patent/US3693775A/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

Images

Classifications

    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01H—ELECTRIC SWITCHES; RELAYS; SELECTORS; EMERGENCY PROTECTIVE DEVICES
    • H01H13/00—Switches having rectilinearly-movable operating part or parts adapted for pushing or pulling in one direction only, e.g. push-button switch
    • H01H13/70—Switches having rectilinearly-movable operating part or parts adapted for pushing or pulling in one direction only, e.g. push-button switch having a plurality of operating members associated with different sets of contacts, e.g. keyboard
    • H01H13/702—Switches having rectilinearly-movable operating part or parts adapted for pushing or pulling in one direction only, e.g. push-button switch having a plurality of operating members associated with different sets of contacts, e.g. keyboard with contacts carried by or formed from layers in a multilayer structure, e.g. membrane switches
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01H—ELECTRIC SWITCHES; RELAYS; SELECTORS; EMERGENCY PROTECTIVE DEVICES
    • H01H2209/00—Layers
    • H01H2209/006—Force isolators
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01H—ELECTRIC SWITCHES; RELAYS; SELECTORS; EMERGENCY PROTECTIVE DEVICES
    • H01H2217/00—Facilitation of operation; Human engineering
    • H01H2217/016—Pressure reduction membrane; Spreader layer
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01H—ELECTRIC SWITCHES; RELAYS; SELECTORS; EMERGENCY PROTECTIVE DEVICES
    • H01H2221/00—Actuators
    • H01H2221/05—Force concentrator; Actuating dimple

Definitions

  • An actuator sheet carries clusters of switch actuating projections aligned with openings which receive deflectable contacts of an array of diaphragm switches.
  • lntersecting ribs are carried on the same side of the actuator sheet as the switch actuating projections, to define isolation zones for the projections corresponding directly to the individual key areas of the keyboard. Integral, raised pressure pads for each key area are formed on the upper surface of the actuator sheet to enhance even pressure distribution over the pertinent switch contact area.
  • the present invention is directed to an improved elastic diaphragm switch assembly which includes a regular array of deflectable diaphragm switch contacts and an elastomeric sheet overlying the array of contacts and which sheet carries a plurality of projections depending therefrom in registration with the contacts for selectively actuating the same.
  • the elastomeric actuator sheet carries a series' of intersecting, straight-line ribs on the same side of the sheet as the rigid projections to define individual, rectangular isolation zones for the projections, which zones correspond in number and position to theunderlying array of switch contacts. This assures prevention of crosstalk or interference problems between adjacent switches when a single key is depressed.
  • the present invention is directed to the same elastomeric sheet being provided with raised pressure pads corresponding to each key position of the keyboard on the surface facing the soft button carried internally within the opening of the rigid frame underlying the keyboard keys.
  • the raised pressure pads provide even pressure distribution over the pertinent contact area when a key is depressed and allow-relaxation of the tolerance requirements for the soft buttons since a variation in pressure pad tolerance will not be felt by any change in switch actuation pressure.
  • the provision of the intersecting straight ribs allows the entire actuator sheet to lie flat on the elastic diaphragm switch sheet, insuring uniform travel of the keys during depression of the same and enhancing uniform alignment of the actuator projection with the deflectable switch contact of the elastic diaphragm.
  • FIG. ,1. is a vertical section of an integrated keyboard incorporating an array of elastic diaphragm switches of prior art design
  • FIG. 2 is a top plan view, partially broken away, of a keyboard shown in FIG. 1;
  • FIG. 3 illustrates an alternative prior art design
  • FIG. 4 is a bottom plan view of a portion of the improved actuator sheet of the present invention as applied to an integrated keyboard similar to that of FIGS.
  • FIG. 5 is a vertical section of a modified manual keyboard similar to that of FIG. 1 but incorporating the improved actuator sheet of the present invention.
  • FIGS. 1 and 2 one form of a prior integrated keying mechanism constituting a manual keyboard which is presently in use is illustrated. It employs a polyurethane elastomer nomenclature sheet 10 which defines the keyboard of the assembly and includes soft flexible keys 11 which, upon depression, cause soft elastomer buttons 16 to force protrusions 21 of an actuator sheet 20 to operate selected diaphragm switches in array 28. Contacts 24 are carried by the elastic diaphragm 23, while contacts 27 are carried on a rigid sheet 30 supported by base 29. Separator sheet 25 of insulative material, normally keeps contacts 24 and 27 apart, but apertures 26 in sheet 25 allow the contacts to close under pressure.
  • the flexible keys 11 may carry visible indicia identifying the same to allow operator-selector depression as evidenced in FIG. 2.
  • a protective sheet 14 Lying below the keyboard sheet 10 is a protective sheet 14, which also may be formed of an elastomer, which serves as a dust cover for sealing the actuating mechanism below from the environment and further facilitating manipulation of sheet 10.
  • the protective sheet 14 is supported by a rigid frame member 15 formed of metal or the like and having circular or square holes 17 aligned concentrically with keys 11. Keys 11 may thus be depressed centrally due to the holes or openings 17.
  • the key buttons 16 formed of a soft elastomer and molded integrally in a pad 18.
  • the elastomers preferably are closed-pore cellular neoprene rubber with low compressive modulus.
  • an actuator sheet 20 comprised, preferably, of a molded neoprene rubber or elastomer and having thereon a plurality of clusters of truncated cone-shaped protrusions or stops 22 and central protrusion 21 in axial alignment with hole 17 and key 11.
  • the four outer protrusions or stops 22 are of similar length and are slightly shorter than and are circumprotrusions lie generally within the area of the individual keys 11.
  • the outer protrusions 22 are rectangularly disposed and spaced from the central protrusion 21, however, they may be circularly disposed instead.
  • the central protrusion 21 is about 6 to 10 mils longer than the outer protrusions 22 which in turn are approximately one eighth inch in length.
  • the central protrusion 21, when depressed, moves the contact 24 into contact with a contact 27 for a given element of switch array 28.
  • a soft key pad 16 and the flexible keys 11 provide a combination of actuating elements with a low spring constant and a long stroke. These latter characteristics are controlled by the stiffness of key pad 16 and keys 11.
  • Of importance is the provision of the discrete projections 22 in a uniform spaced pattern about the central projection 21 since these projections concentrate the actuating force on a given switch within the array 28. Because of the outside projections 22, the actuating force remains constant over the surface of each of the keys 11.
  • protrusions 22 tends to act as a fulcrum, causing areas outside of the ring" of the cluster to rise rather than fall.
  • protrusions 22 are v preferably shorter than the central protrusion 21, they facilitate closure of the contacts by the central protrusion of the switch. Force applied to a given key 11 is distributed by protrusion 21 until protrusions 22 contact the elastic diaphragm 23. Then, however, the force is concentrated on the central protrusion-21. However, as the forces are increased, the forces are spread out to the stops or protrusions 22 so that the greater force is distributed over a relatively larger area of the elastic diaphragm 23 by all of the stops 22 surrounding the central protrusion 21.
  • a modified arrangement for use'with a keyboard with square keys 11 is possible.
  • the peripheral protrusions 22 are eliminated and a unitary stop is formed by an endless rib 32 lying inside of the key area of a key 11 (shown in phantom).
  • the central protrusion 21 lies well inside of the isolation area defined by the individual curved endless rib 32.
  • the rib 32 thus serves as a stop in similar fashion to stops 22 which prevent interference with or from adjacent keys and which absorbs overtravel forces.
  • the individual ribs 32 must be formed under close tolerances at exactly desired locations and the actuator sheet must be precisely positioned with respect to the other elements of the stacked keyboard. Further, since the force for actuation must be transmitted from the key 1 1, through the cover sheet 14, the soft button 16, ribs 32 must be manufactured with cone-shaped projection 21, ribs 32 must be manufactured with relatively close tolerances to insure proper and uniform force application to the central protrusion 21 effecting switch operation. Having thus discussed the prior art, the specific preferred embodiment of the improvements which comprise the invention will now be discussed with reference to the prior art.
  • the keyboard of the present invention involves, principally, a modified actuator sheet illustrated at 120 and being preferably rectangular.
  • like numerals define like elements to the prior art arrangement of FIGS. 1 through 3.
  • sheet 120 is preferably of molded neoprene rubber or similar elastomer, having a medium hardness of about 55 to 65 durometers and, in the illustrated arrangement, is approximately one sixteenth inch in thickness and provided with a plurality of clusters of truncated, cone-shaped protrusions 121 and 122 with the central protrusion 121 surrounded by four, preferably slightly shorter, protrusions 122 circumferentially spaced and concentric with the central protrusion 121.
  • an elastomeric actuator sheet 120 has integrally molded thereon, on the top or upper surface 100, a plurality of individual raised pressure pads 102 corresponding in surface area and generally in configuration to the visual keying areas of keys 11 on the keyboard. While the raised pressure pads 102 are shown as being square, they may be irregular, rectangular or circular in form, depending of course upon the configuration and location of the individual keys 11 of the keyboard.
  • the contact surface 104 of each of the raised pressure pads lies in contact with a soft button 16 of the integral pad 18 and in alignment with its respective key 11.
  • the soft button With the raised pressure pad 102 in contact with the major portion of the soft button 16, the soft button need not have the tolerance requirement of the prior art design. A variation in button tolerance will not be felt by any change in switch actuating pressure due to the presence of the raised pressure pad 102, which assures a more constant pressure pattern for making the switches.
  • the actuator sheet 120 On the underside of the actuator sheet 120 there is provided a plurality of intersecting, straight-line ribs 132 of rectangular cross section which are also integrally molded into the actuator sheet 120.
  • the raised ribs 132 define rectangular isolation zones 106 within which, of course, are carried the protrusions 121422.
  • the raised ribs 132 lie outside the area of pressure pads 102 on the opposite side of the actuator sheet.
  • the raised ribs 132 due to their intersections, define a regular matrix of rectangular isolation zones corresponding directly with the array of rectangular keys 11 of the keyboard 10.
  • the actuator lies flat and parallel with the elastic diaphragm sheet 123, thereby insuring uniform travel for each key being depressed and more uniform alignment of the actuator projection 121, achieving switching of contacts 124 and 127 for each switch location.
  • the actuator constitutes a more reliable, better balanced pressure actuator than the previously used actuator illustrated in FIGS. 1 through 3, inclusive.
  • an elastic diaphragm switch assembly including; an array of deflectable diaphragm switch contacts and an elastomeric sheet overlying said array of contacts with a plurality of projections depending therefrom in registration with respective contacts, the improvement comprising: a series of intersecting ribs carried on the same side of said elastomeric sheet as said projections and defining a matrix of individual rectangular isolation zones for said projections, said zones corresponding in number and position to said array of contacts to eliminate crosstalk and interference problems between adjacent switches.
  • the elastic diaphragm switch assembly as claimed in claim 1 further comprising a keyboard, a rigid frame member lying below said keyboard and carrying key position separator openings, soft button means coupling said keyboard to said elastomeric sheet through said openings and raised pressure pads carried by said elastomeric sheet on the surface of said sheet and facing respective soft button means for each key position to insure even pressure distribution over the switch contact area of each zone.
  • a keyboard comprising: an elastomeric keyboard means bearing indicia and defining keys thereon, an elastomeric actuator sheet including an input surface and an output surface on opposite sides thereof, a rigid frame member having openings therein corresponding to the keys of said keyboard member supporting said keyboard means and positioned intermediate of said keyboard means and said actuator sheet, a plurality of soft elastomeric buttons carried within said frame opening and mechanically coupling said keyboard rality of projections extending outwardly of the output means to said actuator sheet, a plurality of diaphragm switches in an array corresponding to the keys of said keyboard means and having an actuation surface consurface of said elastomeric actuator sheet for contact with the actuation surface of respective diaphragm switches to close contacts of said switches relating to specific-key areas of said keyboard means, one of said projections being responsive to deflection of said actuator sheet for effecting closure of said switch contact and a plurality of additional projections surrounding said one projection for stopping excessive deflection of said one projection, and a plurality of

Landscapes

  • Push-Button Switches (AREA)
  • Compositions Of Macromolecular Compounds (AREA)
  • Polymerisation Methods In General (AREA)
  • Artificial Filaments (AREA)
  • Mounting Of Bearings Or Others (AREA)
  • Rollers For Roller Conveyors For Transfer (AREA)
US51284A 1970-06-30 1970-06-30 Actuator for elastic diaphragm switch keyboard Expired - Lifetime US3693775A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
US5128470A 1970-06-30 1970-06-30

Publications (1)

Publication Number Publication Date
US3693775A true US3693775A (en) 1972-09-26

Family

ID=21970358

Family Applications (1)

Application Number Title Priority Date Filing Date
US51284A Expired - Lifetime US3693775A (en) 1970-06-30 1970-06-30 Actuator for elastic diaphragm switch keyboard

Country Status (15)

Country Link
US (1) US3693775A (enrdf_load_stackoverflow)
JP (1) JPS5250633B1 (enrdf_load_stackoverflow)
BE (1) BE766631R (enrdf_load_stackoverflow)
BR (1) BR7102016D0 (enrdf_load_stackoverflow)
CA (1) CA938969A (enrdf_load_stackoverflow)
DE (1) DE2130233C3 (enrdf_load_stackoverflow)
DK (1) DK134060B (enrdf_load_stackoverflow)
ES (1) ES392708A2 (enrdf_load_stackoverflow)
FI (1) FI59219C (enrdf_load_stackoverflow)
FR (1) FR2095555A6 (enrdf_load_stackoverflow)
GB (1) GB1304312A (enrdf_load_stackoverflow)
IT (1) IT988533B (enrdf_load_stackoverflow)
NL (1) NL164995C (enrdf_load_stackoverflow)
NO (1) NO133859C (enrdf_load_stackoverflow)
SE (1) SE369449B (enrdf_load_stackoverflow)

Cited By (15)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3908100A (en) * 1974-03-25 1975-09-23 Gen Signal Corp Touch blend smooth surface switch assembly
US3955498A (en) * 1975-03-27 1976-05-11 Scott Thaddeus Leroy Electromagnetically actuated printer
US4057710A (en) * 1976-03-29 1977-11-08 Willmott Arthur S Keyboard assembly
US4086451A (en) * 1976-12-06 1978-04-25 Texas Instruments Incorporated Keyboard apparatus
US4231098A (en) * 1974-09-09 1980-10-28 Sharp Kabushiki Kaisha Casing of electronic calculators
US4258096A (en) * 1978-11-09 1981-03-24 Sheldahl, Inc. Composite top membrane for flat panel switch arrays
US4520248A (en) * 1980-08-15 1985-05-28 Rogers Corporation Keyboard assembly
US4671688A (en) * 1985-10-02 1987-06-09 Honeywell Inc. Shielded keyboard
US4972753A (en) * 1987-12-21 1990-11-27 Yamaha Corporation Electronic musical instrument
US5286125A (en) * 1992-11-16 1994-02-15 Digiosia Antonio G Keyboard and key guide frame arrangement
US5579002A (en) * 1993-05-21 1996-11-26 Arthur D. Little Enterprises, Inc. User-configurable control device
US5684279A (en) * 1995-09-12 1997-11-04 Key Tronic Corporation Computer keyboard with improved membrane keyswitch structure having deflection concentration feature
EP1028445A3 (en) * 1999-02-12 2001-05-02 Nokia Mobile Phones Ltd. Support structure for a keypad
US6791480B1 (en) 1998-12-04 2004-09-14 Alan K. Uke Method of preventing and/or alleviating repetitive use injury to electronic computer keyboard operator
WO2011138200A1 (en) * 2010-05-06 2011-11-10 Iee International Electronics & Engineering S.A. Input device

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS5633937Y2 (enrdf_load_stackoverflow) * 1978-04-10 1981-08-11

Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3120583A (en) * 1960-07-01 1964-02-04 Teaching Machines Inc Multiple switch device for selectively interconnecting multiple electrical conductors
US3308253A (en) * 1965-03-25 1967-03-07 Ibm Diaphragm switch having a diaphragm supported on an incompressible layer and an elastomer overlaying the diaphragm
US3382338A (en) * 1966-04-26 1968-05-07 Ibm Pushbutton actuator for elastomeric switch
US3551616A (en) * 1969-01-15 1970-12-29 Ibm Multiple switch encoding device
US3560675A (en) * 1969-05-26 1971-02-02 Ibm Depressible diaphragm overlay switch for displays
US3584162A (en) * 1970-02-16 1971-06-08 Ibm Electrical keyboard switch mechanism with improved resilient diaphragm contact actuator

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3120583A (en) * 1960-07-01 1964-02-04 Teaching Machines Inc Multiple switch device for selectively interconnecting multiple electrical conductors
US3308253A (en) * 1965-03-25 1967-03-07 Ibm Diaphragm switch having a diaphragm supported on an incompressible layer and an elastomer overlaying the diaphragm
US3382338A (en) * 1966-04-26 1968-05-07 Ibm Pushbutton actuator for elastomeric switch
US3551616A (en) * 1969-01-15 1970-12-29 Ibm Multiple switch encoding device
US3560675A (en) * 1969-05-26 1971-02-02 Ibm Depressible diaphragm overlay switch for displays
US3584162A (en) * 1970-02-16 1971-06-08 Ibm Electrical keyboard switch mechanism with improved resilient diaphragm contact actuator

Cited By (17)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3908100A (en) * 1974-03-25 1975-09-23 Gen Signal Corp Touch blend smooth surface switch assembly
US4231098A (en) * 1974-09-09 1980-10-28 Sharp Kabushiki Kaisha Casing of electronic calculators
US3955498A (en) * 1975-03-27 1976-05-11 Scott Thaddeus Leroy Electromagnetically actuated printer
US4057710A (en) * 1976-03-29 1977-11-08 Willmott Arthur S Keyboard assembly
US4086451A (en) * 1976-12-06 1978-04-25 Texas Instruments Incorporated Keyboard apparatus
US4258096A (en) * 1978-11-09 1981-03-24 Sheldahl, Inc. Composite top membrane for flat panel switch arrays
US4520248A (en) * 1980-08-15 1985-05-28 Rogers Corporation Keyboard assembly
US4671688A (en) * 1985-10-02 1987-06-09 Honeywell Inc. Shielded keyboard
US4972753A (en) * 1987-12-21 1990-11-27 Yamaha Corporation Electronic musical instrument
US5286125A (en) * 1992-11-16 1994-02-15 Digiosia Antonio G Keyboard and key guide frame arrangement
US5579002A (en) * 1993-05-21 1996-11-26 Arthur D. Little Enterprises, Inc. User-configurable control device
US5729222A (en) * 1993-05-21 1998-03-17 Jerry Iggulden User-configurable control device
US5684279A (en) * 1995-09-12 1997-11-04 Key Tronic Corporation Computer keyboard with improved membrane keyswitch structure having deflection concentration feature
US6791480B1 (en) 1998-12-04 2004-09-14 Alan K. Uke Method of preventing and/or alleviating repetitive use injury to electronic computer keyboard operator
EP1028445A3 (en) * 1999-02-12 2001-05-02 Nokia Mobile Phones Ltd. Support structure for a keypad
US6614905B1 (en) 1999-02-12 2003-09-02 Nokia Mobile Phones Limited Support structure for a keypad
WO2011138200A1 (en) * 2010-05-06 2011-11-10 Iee International Electronics & Engineering S.A. Input device

Also Published As

Publication number Publication date
NL164995C (nl) 1981-02-16
IT988533B (it) 1975-04-30
DE2130233A1 (de) 1972-01-05
FI59219B (fi) 1981-03-31
DE2130233B2 (de) 1973-04-12
NL7107869A (enrdf_load_stackoverflow) 1972-01-03
FR2095555A6 (enrdf_load_stackoverflow) 1972-02-11
CA938969A (en) 1973-12-25
NO133859B (enrdf_load_stackoverflow) 1976-03-29
GB1304312A (enrdf_load_stackoverflow) 1973-01-24
DE2130233C3 (de) 1973-11-08
DK134060C (enrdf_load_stackoverflow) 1977-02-14
BR7102016D0 (pt) 1973-04-12
NL164995B (nl) 1980-09-15
JPS5250633B1 (enrdf_load_stackoverflow) 1977-12-26
DK134060B (da) 1976-09-06
SE369449B (enrdf_load_stackoverflow) 1974-08-26
FI59219C (fi) 1981-07-10
NO133859C (enrdf_load_stackoverflow) 1976-07-07
JPS471203A (enrdf_load_stackoverflow) 1972-01-21
BE766631R (fr) 1971-10-01
ES392708A2 (es) 1977-12-01

Similar Documents

Publication Publication Date Title
US3693775A (en) Actuator for elastic diaphragm switch keyboard
US3617660A (en) Keyboard actuating mechanism for diaphragm electric switch contact array
US3584162A (en) Electrical keyboard switch mechanism with improved resilient diaphragm contact actuator
US3856998A (en) Keyboard switch assembly with improved operating means
US5360955A (en) Computer keyboard with cantilever switch design and improved PCB/switch membrane interface
US4323740A (en) Keyboard actuator device and keyboard incorporating the device
US4508942A (en) Keyboard switch
US4677268A (en) Elastomeric switch control device
US3818153A (en) Pushbutton switch assembly for keyboards including a bridging conductive, elastomeric diaphragm type contact
US5481074A (en) Computer keyboard with cantilever switch and actuator design
EP0277404B1 (en) Keyboard having lower casing with integral upraised portion for supporting pc board
US4703139A (en) Method in a snap dome switch keyboard assembly for reducing contact bounce time
US4862499A (en) Deformable membrane keypad assembly for public telephones
JPH0216526B2 (enrdf_load_stackoverflow)
JPS5936375B2 (ja) キ−ボ−ド
GB2123213A (en) Panel keyboard electrical switch
US4207443A (en) Key-operated switch and an assemblage of such switches for electronic desk calculators or the like
JP2007134152A (ja) 可動接点およびこれを用いて構成した可動接点体、スイッチ
US3826882A (en) Electric keyboards for office machines
US4820887A (en) Membrane keyboard blockout apparatus
US5298706A (en) Membrane computer keyboard and improved key structure
GB2178235A (en) Keypad
US3723673A (en) Keyboard switch assembly with wire conductor matrix contact array
US3612802A (en) Pushbutton array
US5684279A (en) Computer keyboard with improved membrane keyswitch structure having deflection concentration feature