An improved surface activation technique improves the adhesion of thermal spray coatings, which is useful for engine cylinder bores. The new method includes compressing the cylinder bore surface to create a surface profile on the surface, such as through rolling a roller along the surface. An engine block is also provided, which includes a plurality of cylinder bores, each cylinder bore having an inner surface, and each inner surface having a surface profile that includes a helical groove and other surface profiles formed in the inner surface. A thermal spray coating is formed on the inner surface of each cylinder bore, the thermal spray coating being adhered to the surface profile of the inner surface. A roller assembly for activating the surface is also provided.

An improved surface activation technique improves the adhesion of thermal spray coatings, which is useful for engine cylinder bores. The new method includes compressing the cylinder bore surface to create a surface profile on the surface, such as through rolling a roller along the surface. An engine block is also provided, which includes a plurality of cylinder bores, each cylinder bore having an inner surface, and each inner surface having a surface profile that includes a helical groove and other surface profiles formed in the inner surface. A thermal spray coating is formed on the inner surface of each cylinder bore, the thermal spray coating being adhered to the surface profile of the inner surface. A roller assembly for activating the surface is also provided.

A device for machining a surface of a workpiece includes a workpiece holder configured to rotate the workpiece about a workpiece rotational axis, a tool having a tool rotational axis and at least one blade having a blade radius of curvature and a tool holder configured to position the tool such that an active point of the blade comes into engagement with the workpiece and configured to pivot the tool about the tool rotational axis and to configured to move the tool with an advancing motion such that the active point of the blade shifts along the blade. The advancing motion is defined by a curve having at least a first radius of curvature and a second radius of curvature.

A corrective grinding device for machining a surface to be ground (2A) of a part of revolution (2) with a main central axis (X2), comprises a base (5) to be fixed on the frame (3), a machining head (10) comprising an abrasive belt (11) which is guided along a belt path (12) so as to be pressed against the surface to be ground (2A) in a first penetration direction (Y10), a belt-driving motor (16) arranged to drive the abrasive belt (11) in motion along the belt path (12), a head movement system (23) for moving the machining head (10) on the base (5) in a second feed direction (X10) along the main central axis (X2). In orthogonal projection in a base plane (P10) defined by the feed direction (X10) and the penetration direction (Y10), the projected surface of the abrasive belt (11) overlaps the projected surface of the stator (17) of the belt-driving motor (16).

A corrective grinding device for machining a surface to be ground (2A) of a part of revolution (2) with a main central axis (X2), comprises a base (5) to be fixed on the frame (3), a machining head (10) comprising an abrasive belt (11) which is guided along a belt path (12) so as to be pressed against the surface to be ground (2A) in a first penetration direction (Y10), a belt-driving motor (16) arranged to drive the abrasive belt (11) in motion along the belt path (12), a head movement system (23) for moving the machining head (10) on the base (5) in a second feed direction (X10) along the main central axis (X2). In orthogonal projection in a base plane (P10) defined by the feed direction (X10) and the penetration direction (Y10), the projected surface of the abrasive belt (11) overlaps the projected surface of the stator (17) of the belt-driving motor (16).

To uniformly bring an abrasive into contact with a workpiece and to achieve desired surface roughness. A polishing tool sliding on a narrow part of the workpiece includes an abrasive retaining layer configured to allow an abrasive to be retained on a surface, and an elastic layer that is stacked on the abrasive retaining layer and is configured to press the abrasive retained in the abrasive retaining layer against the workpiece. The elastic layer is preferably elastically deformable over a sliding stroke of the polishing tool, and a driving unit that causes the polishing tool to slide on the workpiece is preferably connected to the polishing tool.

To uniformly bring an abrasive into contact with a workpiece and to achieve desired surface roughness. A polishing tool sliding on a narrow part of the workpiece includes an abrasive retaining layer configured to allow an abrasive to be retained on a surface, and an elastic layer that is stacked on the abrasive retaining layer and is configured to press the abrasive retained in the abrasive retaining layer against the workpiece. The elastic layer is preferably elastically deformable over a sliding stroke of the polishing tool, and a driving unit that causes the polishing tool to slide on the workpiece is preferably connected to the polishing tool.

A grinding arm for grinding workpieces with an inner profile with a grinding wheel. The grinding arm has a tube-shaped base body with a longitudinal axis, in which the grinding wheel is supported at one axial end region. A first drive for the grinding wheel is arranged in its other axial end region. A first transmission system transmits the rotation from the first drive to the grinding wheel. In order to adjust arbitrary angles of inclination of the grinding wheel in the grinding arm, the grinding wheel is arranged on a grinding spindle driven by the first transmission system and rotating around an axis of rotation. The grinding spindle is supported in a carrier body arranged in the base body rotatable around an axis perpendicular to the longitudinal axis as well as perpendicular to the axis of rotation, wherein the axis of rotation and the axis intersect.

A grinding arm for grinding workpieces with an inner profile with a grinding wheel. The grinding arm has a tube-shaped base body with a longitudinal axis, in which the grinding wheel is supported at one axial end region. A first drive for the grinding wheel is arranged in its other axial end region. A first transmission system transmits the rotation from the first drive to the grinding wheel. In order to adjust arbitrary angles of inclination of the grinding wheel in the grinding arm, the grinding wheel is arranged on a grinding spindle driven by the first transmission system and rotating around an axis of rotation. The grinding spindle is supported in a carrier body arranged in the base body rotatable around an axis perpendicular to the longitudinal axis as well as perpendicular to the axis of rotation, wherein the axis of rotation and the axis intersect.

To uniformly bring an abrasive into contact with a workpiece and to achieve desired surface roughness. A polishing tool sliding on a narrow part of the workpiece includes an abrasive retaining layer configured to allow an abrasive to be retained on a surface, and an elastic layer that is stacked on the abrasive retaining layer and is configured to press the abrasive retained in the abrasive retaining layer against the workpiece. The elastic layer is preferably elastically deformable over a sliding stroke of the polishing tool, and a driving unit that causes the polishing tool to slide on the workpiece is preferably connected to the polishing tool.