HYDRAULIC REGULATING DISTRIBUTORS PERMITTING THE CONTROLLED ROTATION OF TWO MEMBERS ABOUT AN AXIS OF ROTATION

摘要

1285375 Folding bridges FRANCE ARMED FORCES MINISTER OF 3 Oct 1969 [4 Oct 1968] 48797/69 Heading E1G [Also in Division F1] A control circuit for maintaining synchronisation of two hydraulic jacks 3, 4 Fig. 1 serving to fold and to unfold half-spans T of a bridge pivoted together at an axis comprises a distributor 8 Fig. 9 with two relatively rotatable parts 17, 18a the relative positions of which determine the ratio of hydraulic feed to and from jacks 3, 4; part 17 being a shaft coaxial with pivot 1, having spaced cylindrical ported chambers and being connected by a slide and link means 18 to a half span T and part Ba surrounding part 17 and connected by 18a to one leg of an invented isosceles triangle 2 pivoted at one corner to axis 1 and at the other two corners to jacks 3, 4. The slide 18 maintains shaft 17 in a fixed position relative to the bisector of the angle between the two members T, T and 18a moves valve part 8a1 according to any difference between the bisector and the vertical. The pressure source is a pump jack 5 fast with one span T actuated by a ram jack 22 fast with a laying machine 23.