Device for selectively interrupting mechanical operation of a manually operated telephone

Claim 1

In an attachment for a tone telephone having a manually actuable telephone number selector keyboard, a first means for selectively interrupting a telephone connection, said first means comprising a bypass switch assembly operable in one position to complete said connection and in another position to interrupt said connection when either the digit "0", indicating the operator, or "1", indicating a long distance code, are initially dialled, and switching means operable to deactivate the bypass switch after the second digit is dialled when the first dialled digit is other than "0" or "1", second means attached to said keyboard for indicating to said first means that a "1" or "0" has been dialled, said second means comprising upper and lower thin sheets of flexible conductive material separated by a flexible insulating sheet including a passageway adjacent to each key, said upper sheet including circular openings around the "1" and "0" keys with conductive metal rings, which are separate and insulated from said upper sheet, surrounding said "1" and "0" keys and covering their associated passageways, contact means in each passageway such that, when any key is pressed, the upper conductive sheet, or the separate ring in the case of the "1" and "0" keys, is placed in electrical contact with the lower conductive sheet.