Patent DE-4498145-C1 (DE)
Title: Notebook computer keyboard
Inventor: KOEHN MATTHIAS-REINHARD
IPC: H01H13/703
Filed: 1994-10-25
Granted: 2003-06-26
Abstract: The flat keyboard structure, for a notebook computer, has a carrier (10,30,32,34) has a pliable and flexible support film (10) which can roll round at least one axis. The switch function system (12,16,20) is flexible to roll round the axis (axes).  Also claimed is a mfg. process, where the switch function system is encapsulated in the structure by casting a plastics material to form the support and cover films, and the peripheral strips to bond the assembly into a one-piece structure. The carrier structure (10,30,32) and the switch function system (12,16,20) and the covering film (26) are generally rectangular. The carrier (10,30,32) has two generally rigid edge strips (30,32) parallel to the rolling axis and two edge strips at right angles to the rolling axis. At leat the first edge strips (30,32) can be detached from the support layer (10), the switch function system (12,16,20) and the covering film (26). At least the second edge strips can wind pliable round the rolling axis.  Part of the keyboard pattern (28) at the covering film (26) acts as an operating surface for the computer mouse.  The plug coupling (34), for connection and disconnection to the date processing unit, is integrated in one of the edge strips (30,32). A control unit, as a SMD component group, is integrated into an edge strip (30,32) as in an illuminating system for the keyboard pattern (28).  A carrier and/or socket plates as an accessory holder can take the support film (10), electrical switch function system (12,16,20) and the edge strips (30,32).  The switch functions system (12,16,20) has free sensor keys generally free of mechanically moved function components, with short-stroke keys fitted to a pliable plate, or as a contact film system in succession from the support film (10) as an electrically conductive layer (14) at the first contact film (12), according to the keyboard pattern (28). with openings (18) in a distance unit (16). A second contact film (20) has an electrically conductive layer (22) at least in zones on the side towards the distance unit (16). An elastically pliable buffer layer (24) is between the second contact film (20) and the covering film (26. The distance film (16) generally covers the whole surface area of the contact films (12,20). The distance unit can also be discrete distance pieces, as circular rings, deployed according to the keyboard pattern (28), and can be incorporated in one of the contact films (12,20) for the contact zones.  One of the contact films (12,20) carries all the discrete conductor paths, with comb-shaped penetrations in to the contact points of the keyboard pattern (28). The contact zones, at the side towards the distance unit, has a complete electrically conductive coating, with the discrete conductor paths carried by the contact film through them. The electrically contact points at the contact films (12,20) are in rows parallel to the rolling axis. Nominal bending lines are also parallel to the rolling axis.  Matching expanded air chambers are formed by the keyboard pattern (28), for use in extreme pressure conditions.  The electrical switch function system (12,16,20) is cast in elastic plastics material as one-piece with the support (10) and covering (26) films, with an edge strip all round. Flow passages in the support (10), and covering (26) films for the switch function system (12,16,20) allow connecting webs to fix the relative positioning of the function components with their interlinking.