PURPOSE: To prevent a trouble from occurring because of the use of sliding plate of weight decreased due to abrasion, by adjusting the pantograph push-up force in proportion to the weight of the sliding plate and push up the pantography by a constant force per unit weight.
CONSTITUTION: When the weight of the sliding plate SL applied to a connecting pipe support 40 decreases due to abrasion, a pressure signal proportional to the deviation from a prescribed value is applied from a pressure regulating valve 43 to a cylinder 45. Thereby, a rack at the front end of the cylinder moves forth, a screw gear 47' of a pressure regulating valve 47 is rotated and adjusting air pressure is supplied into an air reservoir. Elevator arms for the pantograph are operated by the compressed air in the air reservoir through a main cylinder
AOKI HARUO
INAGAKI AKEMI
