Phone guard for locking out long-distance calls

A telephone lock for attachment to a telephone permits a user to dial local calls only with a first predetermined number of digits, where one of the digits is assigned to call an operator. The telephone receiver normally rests upon a set of depressable push-buttons for making contact with the push-buttons of the telephone itself. A lock dialing device is connected to the telephone's dialing device so that a user can dial a selected number of the digits sequentially when the telephone speaker and receiver have been lifted from the set of push-buttons. First and second dialing stop-devices prevent the user from dialing the digit assigned to the operator, and from dialing an additional number of the digits after he has dialed the first number of digits, respectively. A counting device for counting the first number of digits includes a shaft and a gear rotatable on the latter which is formed with a plurality of substantially equispaced longitudinal fingers, one of the fingers being an elongated finger. A torsion spring urges the gear to move in one direction, and the gear may be advanced one angular step equal to the spacing between adjacent fingers when dialing one of the digits. The second dialing stop-means stops the advancement of the gear when a bar attached to the lock's housing impinges on the elongated finger. When the receiver and speaker have been replaced on the set of push-buttons, the dialing device is reset to an initial state.