公开(公告)号：US5218177A

公开(公告)日：1993-06-08

申请号：US805409

申请日：1991-12-10

申请人： Edwin T. Coleman, III ,  Philip M. Cullen ,  Mary L. VanArsdall

发明人： Edwin T. Coleman, III ,  Philip M. Cullen ,  Mary L. VanArsdall

IPC分类号： H01H13/702 ,  H01H13/703

CPC分类号： H01H13/702 ,  H01H13/703 ,  H01H2211/006 ,  H01H2213/014

摘要： First and second membranes carrying contacts located on opposing faces are separated by a third or spacer membrane having holes therein so that a circuit may be completed between the contacts when a force is applied to the first membrane. The first and second membranes and the peripheries of the holes define substantially enclosed switch regions. The first, second and third membrane layers are mechanically held together, without the use of adhesives, in the regions other than the switch regions. Spacer elements are provided between the spacer membrane and one of the first and second membranes. The spacer elements form air pockets such that air may flow between the switch region and the air pockets as the first membrane is depressed and then released. The arrangement provides two advantages. First, it reduces pressure buildup, such as would occur if the membranes were sealed together, when force is applied to the first layer. Secondly, it reduces pressure variations in the switch region where a vacuum would otherwise be created as the first membrane returns to its undepressed position. The contacts thus open more quickly thereby reducing the possibility of contact bounce. The spacer elements might be either conductive or dielectric. If they are conductive they may be applied during the same screening pass that places conductors and contacts on the first or second layer. If they are non-conductive they may be applied during the same screening pass that places a dielectric on the flextail portion of a membrane.

摘要翻译： 位于相对表面上的第一和第二膜承载触点由其中具有孔的第三或间隔膜隔开，使得当力施加到第一膜时可在触点之间完成电路。 第一和第二膜以及孔的周边限定了基本封闭的开关区域。 第一，第二和第三膜层在除了开关区域之外的区域中机械地保持在一起而不使用粘合剂。 间隔元件设置在间隔膜与第一和第二膜中的一个之间。 间隔元件形成气囊，使得当第一膜被压下并释放时，空气可在开关区域和气穴之间流动。 该方案提供了两个优点。 首先，当力施加到第一层时，其减少了压力积聚，例如当膜被密封在一起时会发生。 其次，它降低了开关区域中的压力变化，其中当第一膜返回到其未受压位置时，否则将产生真空。 触点因此更快地打开，从而减少接触反弹的可能性。 间隔元件可以是导电的或电介质的。 如果它们是导电的，则可以在将导体和触点放置在第一层或第二层上的相同筛选过程中施加。 如果它们是非导电的，则它们可以在相同的筛选过程中施加，其中电介质在膜的挠曲部分上放置。