be effective a possible mode of assembly is shown in fig5 where the case is composed of two identical half shells 2a 2b positioned for instance by tenons 18 and cemented or fused together such an arrangement allows insertion of the internal parts of the switch before putting the shells together while still maintaining the rigid character of the case 2 while the realization of the switch as in fig1 to 5 gives good results with a single central fsi e g for push buttons up to sixty millimeters long by thirty wide this structure is no longer suited for all positions of the finger with larger dimension push buttons the realization of fig6 with two fsi 39 s 3a 3b affords a solution satisfactory for buttons of the same width but of a length preferably between sixty and 150 millimeters or more the two fsi 39 s 3a 3b are electrically connected in parallel and disposed essentially at right angles to each end of the push button a difference is that the fixed plate 9 does not cover the entire length of the switch and is held between two pairs of crossbars 43 44 fixed between the long sides of the case 2 the movable plate is made up of two plate elements 8a 8b attached directly to the ends of the push button on its underside and bent at right angles to pass round the extremities of the fixed plate 9 for a sufficient distance to hold the fsi 39 s 3a 3b and their.