Abstract: The present invention relates to an instrument for endoscopic surgical instrument. The invention is characterized by a single control element whose orientation enables the distal part of the instrument to be articulated at any angle, and whose rotation (about its own axis) enables the orientation of this distal part about its lengthwise axis to be controlled. The position of this single control element, in front of the handle, is ergonomic and reflects the simple rotation controls existing in the rigid, straight-line instruments available on the market and habitually used by surgeons. In general, the endoscopic surgical instrument comprises a gripping and control handle, an elongated tubular part, a ball joint, a terminal or distal part, and a tool carried by the end of distal part.

Abstract: The present invention relates to a rotary hydraulic jack device. This jack device comprises a rotary hydraulic joint whose rotary part is formed by a tubular extension of a first end cover of the jack cylinder. Two check valves and the rotary joint are respectively inserted in two main pipes which alternately connect the two compartments of the jack cylinder to a source of pressurized hydraulic fluid and to a tank at atmospheric pressure. Each check valve is controlled by an auxiliary pipe connected to one of the main pipes upstream of the other check valve. The two check valves are respectively located in tight chambers arranged in the first end cover of the jack cylinder. This jack device may be used to control the part of clamping chuck of a machine tool.

Abstract: A rotary hydraulic jack having two jack compartments, comprising a rotary hydraulic joint for the supply of hydraulic liquid to and the evacuation of hydraulic liquid from at least one of the compartments. The hydraulic joint comprises a fixed, hollow cylindrical part and a rotary part supported by bearings with a narrow annular gap between itself and the fixed part. A passageway leads to said compartment and has a portion in each of the fixed and rotary parts, the passageway portion in the rotary part being equipped with at least one non-return device for hydraulic liquid supplied to said compartment. A groove is provided in at least one of the fixed and rotary parts and communicates with the passageway portions in the fixed and rotary parts. Means is provided for supplying gas under pressure to the annular gap betwen the fixed and rotary parts for the purpose of expelling residual oil from the gap after the supply of hydraulic liquid under pressure to said compartment via the passageway has been completed.

Abstract: A double-acting rotary hydraulic jack having two jack compartments, comprising a rotary hydraulic joint for the supply of hydraulic liquid to and the evacuation of hydraulic liquid from the compartments. The two compartments of the jack each communicate with at least one axial boring in a rotary part of the jack which is not axially movable. In this boring a movable piston bears against the head of a guide rod for a spring which itself bears against the rotary part of the jack. The ends of the rods, externally of the borings, are secured to a member coaxial with the jack, for example a sleeve, whose axial position is monitored by a displacement detector, so as to give an indication of the working pressure in the active jack compartment.

Abstract: A rotary spindle assembly for a machine tool including a spindle supported at opposite ends by oppositely directed roller bearings. The bearing at that end of the spindle opposite to the nose end is an outer race which is axially slidable in a housing, and a plurality of compression springs are arranged between the outer race and an annular thrust block to bias the outer race away from the axial center of the spindle. Elements are provided for varying the total biasing force on the outer race and the apparatus includes a regulator for controlling the force-varying elements. The force varying elements may be apparatus for applying hydraulic pressure to supplement the biasing force or apparatus for modifying the initial compression state of the springs. The axial force on the outer race reduces or eliminates play in the bearings.