The invention relates to a large-stroke tensioning device in a wheel machining process. The large-stroke tensioning device in the wheel machining process comprises a base, a servo motor, a mounting plate, a connecting plate, a shaft sleeve, an oil cylinder, a gland, hearings, a connecting shaft, a chassis, positioning pins, a flange plate, springs, expanding sections, an expanding core, a protector and the like. The large-stroke tensioning device can meet requirements of clamping and positioning of a wheel, and meanwhile has the characteristics of simple structure, convenience in manufacturing, stable performance and capability of meeting machining requirements on precision.

There is provided a rotary table device including: a rotary table; a center shaft erected toward the rotary table; a housing including an inner peripheral surface having a circular cross section over a predetermined range along a rotation axis; a center sleeve including an outer peripheral surface having a circular cross section corresponding to the inner peripheral surface, and the outer peripheral surface being concentric with the inner peripheral surface; a plurality of recesses formed in at least one of the inner circumferential surface and the outer circumferential surface; a plurality of O-rings disposed to be sandwiched between the inner peripheral surface and the outer peripheral surface; an in-housing fluid flow path formed inside the housing; and a plurality of in-sleeve fluid flow paths formed inside the center sleeve.

The device (1) for the locking of pieces on machine tools comprises: a base body (2, 3, 4) fixable to a machine tool (M); a gripping assembly (5, 6, 7) for gripping a piece (P) to be machined having a cavity (C) with a cavity axis (A1), the gripping assembly (5, 6, 7) comprising: a main head (5) having a main axis (A3) and associated with the base body (2, 3, 4) with a lateral play adapted to allow the shift of the main head (5) along a plane of alignment (B) substantially orthogonal to the main axis (A3); at least two self-centering locking elements (6) associated with the main head (5) in a movable way; and movement means (7) of the self-centering locking elements (6); removable locking means (18) adapted to temporarily lock the main head (5).

The invention relates to a large-stroke tensioning device in a wheel machining process. The large-stroke tensioning device in the wheel machining process comprises a base (1), a servo motor (2), a mounting plate (3), a connecting plate (4), a shaft sleeve (5), an oil cylinder (6), a gland (7), bearings (8), a connecting shaft (9), a chassis (10), positioning pins (11), a flange plate (12), springs (13), sliding pedals (14), an expanding core (15), a protector (16) and the like. The large-stroke tensioning device can meet requirements of clamping and positioning of a wheel, and meanwhile has the characteristics of simple structure, convenience in manufacturing, stable performance and capability of meeting machining requirements on precision.

The device (1) for the locking of pieces on machine tools comprises:a base body (2, 3, 4) fixable to a machine tool (M);a gripping assembly (5, 6, 7) for gripping a piece (P) to be machined having a cavity (C) with a cavity axis (A1), the gripping assembly (5, 6, 7) comprising:a main head (5) having a main axis (A3) and associated with the base body (2, 3, 4) with a lateral play adapted to allow the shift of the main head (5) along a plane of alignment (B) substantially orthogonal to the main axis (A3);at least two self-centering locking elements (6) associated with the main head (5) in a movable way; andmovement means (7) of the self-centering locking elements (6);removable locking means (18) adapted to temporarily lock the main head (5).

There is provided a rotary table device including: a rotary table; a center shaft erected toward the rotary table; a housing including an inner peripheral surface having a circular cross section over a predetermined range along a rotation axis; a center sleeve including an outer peripheral surface having a circular cross section corresponding to the inner peripheral surface, and the outer peripheral surface being concentric with the inner peripheral surface; a plurality of recesses formed in at least one of the inner circumferential surface and the outer circumferential surface; a plurality of O-rings disposed to be sandwiched between the inner peripheral surface and the outer peripheral surface; an in-housing fluid flow path formed inside the housing; and a plurality of in-sleeve fluid flow paths formed inside the center sleeve.