Abstract: A spindle unit comprises a rolling bearing including an outer ring having an outer ring raceway on an inner peripheral surface, an inner ring having an inner ring raceway on an outer peripheral surface, and rolling elements provided rollably between the outer ring raceway and the inner ring raceway, whereby a spindle is borne rotatably in a housing, and a grease supply system for supplying a grease to an inside of the rolling bearing, wherein the grease supply system supplies the grease such that a supply amount in one shot is set to 0.004 cc to 0.1 cc.

Abstract: A machine tool including a bed; a work table horizontally movable on the bed; a column extending from the bed; a spindle head movable on the column; an outer cylinder attached inside the spindle head; a stator of a built-in motor; and a spindle sub-cartridge. The spindle sub-cartridge includes a vertical rotating shaft; a front side bearing having an inner ring fitted to a front end of the rotating shaft and an outer ring fitted to a front housing; a rotor of the built-in motor; a rear side bearing having an inner ring fitted to a rear end of the rotating shaft and an outer ring fitted to a bearing sleeve. The movable range of the spindle head in the vertical direction is longer than a length necessary for inserting the spindle sub-cartridge into the spindle head. The spindle sub-cartridge is can be disassembled and assembled integrally with respect to the spindle head.

Abstract: A spindle apparatus which facilitates assembling and removing operations at the time of maintenance and which is low cost. In the invention, the diameter becomes smaller in the order of an inner peripheral diameter of an outer cylinder (3), an inside diameter of a stator (4), and an outside diameter of a bearing sleeve (11); a sub-assembly (2) made up of a front housing (8), a rotating shaft (6), and the bearing sleeve (11) is withdrawable from the outer cylinder (3); and the diameter of a rotating part in an arbitrary section located rearwardly of the bearing sleeve (11) is made smaller than a minimum diameter of a non-rotating part between a rear end of the bearing sleeve (11) and the section.

Abstract: A ball bearing for spindle turning device for use in the spindle turning device of a machine tool, and a spindle turning device for a machine tool using the same, which is compatible with machine tools whose recent trend is for more composite configurations while maintaining and achieving higher accuracy (higher rotational accuracy), greater stiffness and reductions in torque and heat generation is to be provided. In a ball bearing for spindle turning device for use in the spindle turning device of a machine tool, the sectional size ratio (B/H) between the axially cut sectional width B and the radially cut sectional height H is set to be (B/H)<0.63 where it is a single row ball bearing or the sectional size ratio (B2/H2) between the axially cut sectional width B2 and the radially cut sectional height H2 (B2/H2)<1.2 where it is a double row ball bearing.

Abstract: An object of the invention is to provide a spindle apparatus which facilitates assembling and removing operations at the time of maintenance and which is low cost. In the invention, the diameter becomes smaller in the order of an inner peripheral diameter of an outer cylinder (3), an inside diameter of a stator (4), and an outside diameter of a bearing sleeve (11); a sub-assembly (2) made up of a front housing (8), a rotating shaft (6), and the bearing sleeve (11) is withdrawable from the outer cylinder (3); and the diameter of a rotating part in an arbitrary section located rearwardly of the bearing sleeve (11) is made smaller than a minimum diameter of a non-rotating part between a rear end of the bearing sleeve (11) and the section.

Abstract: An object of the invention is to provide a spindle apparatus which facilitates assembling and removing operations at the time of maintenance and which is low cost. In the invention, the diameter becomes smaller in the order of an inner peripheral diameter of an outer cylinder (3), an inside diameter of a stator (4), and an outside diameter of a bearing sleeve (11); a sub-assembly (2) made up of a front housing (8), a rotating shaft (6), and the bearing sleeve (11) is withdrawable from the outer cylinder (3); and the diameter of a rotating part in an arbitrary section located rearwardly of the bearing sleeve (11) is made smaller than a minimum diameter of a non-rotating part between a rear end of the bearing sleeve (11) and the section.

Abstract: An object of the invention is to provide a spindle apparatus which facilitates assembling and removing operations at the time of maintenance and which is low cost. In the invention, the diameter becomes smaller in the order of an inner peripheral diameter of an outer cylinder (3), an inside diameter of a stator (4), and an outside diameter of a bearing sleeve (11); a sub-assembly (2) made up of a front housing (8), a rotating shaft (6), and the bearing sleeve (11) is withdrawable from the outer cylinder (3); and the diameter of a rotating part in an arbitrary section located rearwardly of the bearing sleeve (11) is made smaller than a minimum diameter of a non-rotating part between a rear end of the bearing sleeve (11) and the section.

Abstract: A spindle unit comprises a rolling bearing including an outer ring having an outer ring raceway on an inner peripheral surface, an inner ring having an inner ring raceway on an outer peripheral surface, and rolling elements provided rollably between the outer ring raceway and the inner ring raceway, whereby a spindle is borne rotatably in a housing, and a grease supply system for supplying a grease to an inside of the rolling bearing, wherein the grease supply system supplies the grease such that a supply amount in one shot is set to 0.004 cc to 0.1 cc.

Abstract: An object of the invention is to provide a spindle apparatus which facilitates assembling and removing operations at the time of maintenance and which is low cost. In the invention, the diameter becomes smaller in the order of an inner peripheral diameter of an outer cylinder (3), an inside diameter of a stator (4), and an outside diameter of a bearing sleeve (11); a sub-assembly (2) made up of a front housing (8), a rotating shaft (6), and the bearing sleeve (11) is withdrawable from the outer cylinder (3); and the diameter of a rotating part in an arbitrary section located rearwardly of the bearing sleeve (11) is made smaller than a minimum diameter of a non-rotating part between a rear end of the bearing sleeve (11) and the section.