Keyboard switch arrangement and key switch useable therein

[4. A keyboard switch arrangement comprising in combination:

• a base plate (46);
• a plurality of keys each including:
• a key stem (35) in the form of a cylindrical portion (36) and having a disk-shaped flange (36a) at the lower end and retaining pieces outwardly extending,
• a push-button attached to the upper end of said cylindrical portion, and
• a key stem holder block (1) mounted on said base plate (46) including a guide slot and guide portions for preventing said key stem from slipping out so disposed that said cylindrical portion slides in said guide slot and said retaining pieces are movably inserted in said guide portions, said guide slot and said guide portions being formed at the upper portion and in the side wall of said holder block, said holder block having a groove on the one outer side wall, a ridge on the opposite outer side wall for being fitted in the groove of a similar adjacent holder block, a plurality of grooves on another outer side wall and a ridge on the other opposite side wall for selectively being fitted in the groove of a similar adjacent holder block;
• a plurality of resilient means (42) each connected to one of said push-buttons each having a restoring force against deformation by depressing said push-button consisting of an inverted cup-like cone;
• and ,
• a plurality of switching means (41) each corresponding to one of said key stems and said resilient means and turning to switch ON when said push-button is pushed down, said switching means each including a pair of fixed electrodes provided on said base plate covered by an electrically insulating layer on the surface, and a resilient member made of an electrically insulating material with the lower end having an electrode layer, said resilient member being attached to the reverse side of upper end of said cone, said electrode layer and said fixed electrodes constituting a capacitor switch.]

[5. A keyboard switch arrangement comprising in combination

• a. a base plate having engaging holes therein;
• b. a plurality of keys arranged side by side on said base plate each including a key stem, a push button thereon, a key stem holder block with outer side wall and a lowest portion thereof for preventing said key stem from slipping out, affixed on said base plate including engaging projections provided at said lowest portion inserted into corresponding engaging holes formed in said base plate, and coupling means provided on said outer side walls of said holder block, including vertically extending ridges and grooves, so arranged and disposed that a ridge of said one holder block fits into a corresponding groove of an adjacent holder block;
• c. a plurality of resilient means each consisting of an inverted cup-like resilient cone disposed between each key stem and said base plate, and said resilient means each having a restoring force against deformation by manipulative depressing of said push button;
• and
• d. a plurality of capacitor switches corresponding to each key, said capacitor switches each including a pair of fixed electrodes on said base plate covered by an electrically insulating layer on the surface and a movable electrode layer attached to the inner surface of top end of said cone, the capacity of static electricity between said pair of fixed electrodes being increased to turn the switch on when said push button is manipulated and pushed down against the restoring force of said cone.]

[7. A keyboard switch arrangement comprising in combination:

• a. a base plate having engaging holes therein;
• b. a plurality of keys arranged side by side on said base plate each including a key stem in the form of a cylindrical portion with upper and lower ends having a disc-shaped flange at said lower end and outwardly extending retaining pieces, a push button attached to said upper end, a key stem holder block with outer side walls an upper and a lowest portion, fixed on said base plate including engaging projections provided at said lowest portion inserted into corresponding engaging holes formed in said base plate, said holder block including a guide slot and guide portions for preventing said key stem from slipping out and turning, so disposed that said key stem cylindrical portion slides in said guide slot and retaining pieces movably inserted in said guide portions, said guide slot being formed at said key stem holder block upper portion and said guide portions being defined in said side wall of said holder block, and coupling means formed on said outer side walls of said holder block and comprising a groove on one outer side wall, a ridge on the opposite outer side wall adopted and designed to fit in the groove of another adjacent holder block, said coupling means stably interlocking the holder block with adjacent holder blocks and arranging the holder blocks in various modes on said base plate by selectively fitting a ridge of one holder block into a groove of another holder block;
• c. a plurality of resilient means each consisting of an inverted cup-like resilient cone disposed between said base plate and said disc-shaped flange of each key stem, said resilient means each having a restoring force against deformation by manipulative depressing of said push button;
• and,
• d. a plurality of capacitor switches corresponding to each key, each including a pair of fixed electrodes provided on said base plate covered by an electrically insulating layer on the surface and a movable electrode layer attached to the inner surface of top end of said cone, the capacity of static electricity between said pair of fixed electrodes being increased to turn the switch on when said push button is manipulated to be pused down against the restoring force of said cone as said electrode layer is brought into contact with said insulating layer on said pair of fixed electrodes.]

[8. A keyboard switch arrangement comprising in combination:

• a. a base plate having engaging holes therein;
• b. a plurality of key switch units arranged side by side on said base plate, each including a key stem, a push button attached thereon, key stem holder block with four outer side walls, an upper and lowest portions fixed on said base plate, preventing said key stem from slipping out, including engaging projections provided at said lowest portion inserted into corresponding engaging holes formed in said base plate, said holder blocks having substantially a square shape in cross-section, and having at least one wall comprising thereon a plurality of vertically oriented grooves, and switch means located within said holder blocks operated by manipulative depressing said push button;
• c. coupling means provided on said outer side walls of each of said holder blocks and comprising a plurality of grooves on a first side wall, a ridge on a second side wall opposite to said first side wall, a groove on a third side wall and a ridge on a fourth side wall opposite to said third side wall, said ridges and grooves extending vertically on said respective outer side walls, said coupling means interlocking one holder block with adjacent holder blocks and holding said holder blocks stably in various modes on said base plate in a manner that a ridge on a fourth side wall of one block is fitted with a groove on a third side wall of an adjacent holder block, and a ridge on a second side wall of the one block is selectively fitted with one of grooves on a first side wall of another
• adjacent holder block.]

A key switch unit, for use in a keyboard arrangement, comprising:

• a base plate having a pair of fixed electrodes which are separated by a non-conductive area;
• a key unit dismountably retained on said base plate, said unit including a key stem with a push button on top thereof and a key stem holder in slidable engagement with said key stem;
• a movable electrode mechanism, disposed between said key unit and said base plate, comprising, assembled into one body, (a) an inverted cup-like resilient cone having a restoring force against deformation by manual depressing of said push button, said cone being provided with an outwardly directed flange extending around the opening thereof, (b) a resilient member, made of an insulating material, fixed to an upper end of said resilient cone and positioned below said upper end, and (c) a movable electrode layer fixed to a lower end of said resilient member;
• and
• an electrically insulating layer disposed between said pair of fixed electrodes and said movable electrode layer so as to form a capacitor switch in combination with said fixed and movable electrodes,
• wherein said movable electrode layer is movable downwardly to switch ON when said push button is manually depressed and upwardly to switch OFF by the restoring force of said resilient cone, and
• wherein said outwardly directed flange of said cup-like resilient cone is held stably in position between abutting portions of said key stem holder and an upper surface of said plate, thereby causing said cone to envelop said capacitor switch, with the opening thereof contacting the surface of said base plate, and causing said movable electrode mechanism to be retained stably on said base plate while remaining easily removable by means of dismounting said key stem holder from said base plate.

A keyboard switch arrangement, comprising in combination:

• a base plate having plural pairs of fixed electrodes thereon;
• a plurality of key units, each key unit being easily mountable and dismountable on said base plate in association with one of said pairs of fixed electrodes, and each said key unit being arranged in contiguous relation to one another when mounted, each unit including (a) a key stem having a pushbutton on top thereof, and (b) a key stem holder block in slidable engagement with said key stem and having outer side walls;
• a plurality of movable electrode mechanisms, each electrode mechanism being retained by each of said key units on said base plate opposite the associated one of said pairs of fixed electrodes, and each comprising, assembled into one body, (a) an inverted cup-like resilient cone having a restoring force against deformation by manual depressing of said push button said cone being provided with an outwardly directed flange extending around the opening thereof, (b) a resilient member, made of an insulating material, fixed to an upper end of said resilient cone and positioned below said upper end, and (c) a movable electrode layer fixed to a lower end of said resilient member;
• and
• an electrical insulating layer disposed between each said pair of fixed electrodes and said associated movable electrode layer so as to form a plurality of capacitor switches in combination with each said fixed electrode pair and the associated said movable electrode layer,
• wherein each said movable electrode layer is movable downwardly to switch ON when said associated push button is manually depressed and upwardly to switch OFF by said restoring force of said associated resilient cone, and
• wherein said outwardly directed flange of each said cup-like resilient cone is held stably in position between abutting portions of the associated said key stem holder block and an upper surface of said base plate, thereby causing each said cone to envelop the associated said capacitor switch, with the opening of each said cone contacting the surface of said base plate, and causing each said movable electrode mechanism to be retained stably on said base plate, while remaining easily removable by means of dismounting the associated said key stem holder block from said
• base plate.