Abstract: The present invention relates to a high-pressure hydraulic valve in which the housing (1) at least and also preferably the operational parts, such as the main control piston (3), the manometer piston (6) and the like which are arranged inside said housing (1) and influence the hydraulic oil flow, are made of an aluminium alloy that can be hardened and tempered. The weight of the high-pressure hydraulic valve can therefore be substantially reduced. The surfaces of the parts made of the aluminium alloy that can be hardened and tempered are advantageously submitted to anodic oxidation in order to increase even more their wear resistance. This type of high-pressure hydraulic valve with a particularly light weight is mainly intended for use in mobile hydraulic systems such as those used in mobile cranes, in lifting platforms and in excavators.

Abstract: A device for black and white, color, stereo picture, holographic picture and stereo and other amplified sound reproduction and reception is described, which is characterized by a hinged housing A and B, one portion of which contains the picture reproduction screen 1. A pair of directional speaker units 2a+2b are integrated in the hinge section of the device. Sound and picture reception units are located in the housing along with touch controls and auxiliary sockets which extend through the wall of the housing B and are located at the surfaces 3, 4a, and 4b.

Abstract: A hydraulic flow control apparatus is provided which is adapted to provide a constant pressure differential between a pump and an external load. The apparatus includes a housing, and a balance piston slideably mounted therein. The pump pressure acts to bias the piston in a direction toward a pump bypass position, and the piston is urged in the other direction and toward its operating position by the consumer pressure and a spring. Means are also provided whereby the pressure of the pump necessary to move the piston toward its bypass position and against the force of the spring, may be minimized during operation in the idling mode, to thereby minimize power consumption.

Abstract: A hydraulic flow control apparatus is provided which is adapted to provide a constant pressure differential between a pump and an external load. the apparatus includes a housing, and a balance piston slideably mounted therein. The pump pressure acts to bias the piston in a direction toward a pump bypass position, and the piston is urged in the other direction and toward its operating position by the consumer pressure and a spring. Means are also provided whereby the pressure of the pump necessary to move the piston toward its bypass position and against the force of the spring, may be minimized during operation in the idling mode, to thereby minimize power consumption.