111 F. 398 | 6th Cir. | 1901
This case involves the validity of the eighth claim of the Anderson patent, No. 412,155, for improvements in trolleys for electric railway service. A consideration of the record in this cause shows that with the advent of the under-running trolley, now in common use in propelling street cars, there arose the necessity of deviling a means by which the current of electricit}r could be readily and safely transmitted from the conducting wire down the swinging arm of the trolley, thence to the motor beneath the cars. The top of this swinging arm had been provided with a frame or harp within which was the trolley wheel held in contact with the transmitting wire b)1' the pressure exerted by the spring attached to the opposite end of the trolley pole at the top of the. car. The electrical current in the propulsion of the car passes from the wire to the wheel, thence to the frame or harp, and down the trolley pole. It was found in practical operation highly necessary to accomplish this purpose in such manner as to prevent in
We find no error in the decree of the circuit court, and the same will be affirmed.