Abstract: A feed screw mechanism includes a nut having a female thread, and a feed screw shaft having a male thread screw-engaged with the female thread. A thrust pocket is formed along a flank of the female thread of the nut, and pressurized fluid is supplied thereto. A plurality of separated radial pockets are formed on the crest surface of the female thread of the nut, and pressurized fluid is supplied thereto. The thrust pocket is a continuous spiral groove formed along the flank of the female thread of the nut. This structure provides sufficient rigidity in both the radial and thrust directions while reducing the size of the feed screw mechanism.

Abstract: A screw-nut feed mechanism for effecting displacement of a movable table on a guiding base or bed in accordance with rotation of a feed screw shaft mounted on the guiding base. Ther feed mechanism includes a ball nut assembly threadedly coupled with the feed screw shaft, and a floatably supporting member for floatably supporting the ball nut assembly. The floatably supporting member is composed of a board having a predetermined thickness in a direction parallel to the rotational axis of the feed screw shaft.

Abstract: In a method and a device for treating a machined surface of a workpiece made of a brittle material, a laser beam generated by a laser oscillator is applied to the machined surface of the workpiece while the workpiece is relatively moved with respect to the laser beam. Additiives and impurities exsisting in cracks generated on the machined surface melt due to thermal energy of the laser beam thereby to eliminate the cracks and improve the strength of the workpiece.

Abstract: A device for detecting the position of a wheel head of a grinding machine is provided with a housing secured to the wheel head and a support rod secured at its opposite ends to a stationary base in parallel relation with the moving direction of the wheel head. The support rod passes through the housing at a pair of holes formed on opposite end walls of the housing. A linear scale is secured to the housing within the housing, and a scanning unit is fixed on the support rod within said housing for reading scale gratings on the linear scale when the housing is moved bodily with the wheel head relative to the support rod.

Abstract: A regulating wheel dressing system in a centerless grinder, having a dressing tool for dressing a regulating wheel, which dressing tool is adapted to be feed-controlled in a direction parallel to the axis of rotation of the regulating wheel and also in a crossing direction by a feed control means, which in turn is controlled biaxially simultaneously by a control means. Coordinate values of plural points on a rotated hyperboloid of one sheet of revolution to be formed on the regulating wheel are calculated and the dressing tool is feed-controlled for coordinate interpolation between the plural points with those coordinate values as target points. The regulating wheel can be dressed to the rotated hyperboloid of one sheet of revolution in high accuracy independently of changes of its diameter and even where it is stepped for supporting a stepped work.