Abstract: An improved actuating device for school bus safety unit, such as crossing arms and the like, which includes an arrangement for driving and controlling the crossing arm in a continuous predetermined arcuate path of movement, with the safety device being moved continuously back and forth in a sweeping motion that provides a moving barrier in areas adjacent the school bus where children may be placed in an unsafe situation, such as immediately adjacent the front bumper of the bus which is outside of the normal line of vision of the school bus operator. In one embodiment, an extendable line is anchored to the bus at one or both ends, and an intermediate portion of the line is engaged by the moving safety unit, whereby the line itself creates a changing barrier as the safety unit sweeps through its path of movement.

Abstract: Apparatus for activating a safety device hingedly mounted on a shool bus to swing it out to an outstretched position when the bus door is opened and to return the device to its retracted position when the bus door is closed. The system includes a control switch which is caused to close when the door is opened and to open when the door is closed. Associated with the control switch is a control circuit for connecting a DC power supply to a unidirectional DC motor operatively coupled through an eccentric drive and a link arm to the safety device whereby in the course of a single cycle of motor rotation, during one half of the cycle the device is caused to swing out to its fully outstretched position, and during the other half, the device is caused to return to its fully retracted position.

Abstract: A protective guard is provided for a school bus. A series of telescoping members retracts along the front of the bus, and are in a compact form when the bus is moving. When the school bus stops two of the members telescope outwardly in series and extend across the lane of oncoming traffic. The members are so long and strong that any motorist attempting to pass the bus will damage his car. Flashing red lights are mounted on the extended members. The members are extended and retracted by a lead screw. The lead screw, when it extends the telescoping members, first drives the innermost member outwardly and away from the other movable member. The lead screw then engages the other movable member and drives it outwardly and it carries the innermost member to its ultimate extended position.

Abstract: The apparatus is provided with a unidirectional motor operatively coupled to the hinged sign through an eccentric drive by a link arm which incorporates a pre-loaded helical compression spring to prevent damage to the link arm should an attempt be made to forcibly swing the sign. Two normally-closed limit switches are associated with the link arm whereby in the course of a motor operating cycle, the stop sign is caused by the link arm to swing out to its outstretched position, at which point one limit switch opens, and then to return to its retracted position, at which point the other limit switch opens. The limit switches are included in a control circuit which supplies power to the motor. The control circuit is responsive to a door switch associated with the bus door so that when the door is open, the door switch is then closed, and power is supplied to the motor through one limit switch until the sign reaches its outstretched position, at which point this limit switch is opened to cut off the motor.