Abstract: The invention relates to a reciprocating hydraulic motor having a differential piston interposed between an inlet pipe for fluid at a pressure P1 and an exhaust pipe for fluid at a pressure P2 which is less than the pressure P1 The moving assembly constituted by the different-section pistons that slide in a stepped cylinder includes a flap having two positions and controlling three ports, the flap being mounted to pivot about an axis. In each of its positions, the flap bears against two wall portions disposed on opposite sides of the flap and at different distances from the pivot axis so that the effect of the pressures P1 and P2 on the faces of the flap is to establish a positive closure torque.

Abstract: A dosing device is provided for introducing small doses of a liquid contained in a first chamber into a second liquid flowing in a second chamber. The device includes a body traversed by a bore which fluidly connects the chambers to one another and in which slides a push pin mounted on a sliding member and a follower pin mounted freely between the push pin and an abutment bar attached to the sliding member. The sliding member reciprocates parallel to the axis of the bore whereby the follower pin is pushed in one direction by the abutment bar and in the opposite direction by the push pin. A space separating the follower pin from the push pin constitutes the dosing chamber which is displaced between the first and second chambers.

Abstract: A device for injecting additive products into a liquid includes a conduit in which flows a liquid, a nozzle which penetrates into the conduit for injecting additive products, and a chamber in fluid communication with the conduit and situated above the latter. The nozzle is situated within the chamber, and means are provided for introducing and maintaining a gaseous atmosphere in the chamber whereby the nozzle is entirely contained in the gaseous atmosphere.

Abstract: A device for setting up a contact connection between independent electrical circuits, which comprises a plate made of magnetic material 1 on which is placed a sheet 2 of insulating material, supporting at least two independent conductor circuits 3, 4 adapted to be connected together by means of a magnetized conductive member 6, held in position by the attraction of the said magnetic plate 1.The invention relates to a device used in games and in the audio-visual field.

Abstract: A device for injecting adjuvant into a liquid employing a stepped piston in a stepped cylinder with a valve in the piston triggered to open and close at opposite ends of the piston travel to cause a reversal of piston movement while a further piston integral with the first mentioned piston operates to pump metered quantities of adjuvant into the stepped cylinder.