Abstract: An excavator comprising a plurality of buckets mounted on an endless chain on a jib, and a bottomless scoop at the working end of the jib through which the buckets pass in use. The scoop is power operated to break up the soil being excavated, and as each bucket passes through the scoop it co-operates with the scoop to form a complete digging bucket.

Abstract: In a pump or motor having a plurality of radial pistons adapted to perform a plurality of strokes per revolution, a stator, a rotor and a fluid-distributor slide valve fast with the stator and having a radially extending plane face opposite a radially extending plane face of said rotor, said slide valve is provided in a chamber which communicates with the interface between said faces and, by a pressure-maintaining device, with a substantially unpressurised enclosure such that the effect on said slide valve of the pressure of fluid in said chamber will substantially balance the effect of pressure of fluid acting on said interface between said faces.

Abstract: This invention relates to a telescopic jack constituted by a main cylinder, a first piston sliding in said main cylinder, a first piston rod fast with the first piston which passes in tight manner through a first bottom of the cylinder, a second piston which may be disposed in a bore of the first rod and is mounted to slide with respect to the first piston, and by a second piston rod which is fast with the second piston.The second piston rod passes through the second bottom of the cylinder whilst the piston is separable from the rod.One application of the invention is the production of an inexpensive telescopic jack.

Abstract: The present invention relates to the construction of a slide connecting two bodies.A male member is fixed to the first body whilst a female member is fixed to the second body, whilst bolts for attaching the ring gear to the said first body are arranged to the right of the latter.The invention is more particularly applicable to the construction of "roller rings" on a public works vehicle having a pivoting turret.

Abstract: A telescopic structure comprises an inner and an outer member telescopic relative to each other, and means for supporting and/or guiding one member relative to the other member, comprising a pair of wheels mounted on each member and positioned between the members, the wheels on one member bearing on parallel runways fixed to the other member, the runways each having an at least partly circular section with the peripheral surfaces of the wheels bearing on the runways being correspondingly toroidally shaped to have geometric projections in a plane perpendicular to the direction of extent of the runways extending parallel and perpendicular to the rotational axes of the wheels.