A cutting insert according to an aspect includes a base portion and a cutting portion. The cutting portion includes a front end surface, an top surface, a first lateral surface, a second lateral surface, a front cutting edge, and a lateral cutting edge. The front cutting edge includes a first cutting edge and a second cutting edge, and a radius of curvature of the first cutting edge is greater than a radius of curvature of the second cutting edge.

A cutter insert tool holder effects bidirectional linear cuts on a work surface. The tool holder includes two elongated slots sized to accommodate first and second cutting insert holders. The tool holder includes an actuator arm that is placed in a first pivoting position by contacting the work surface while the tool holder is displaced along the work surface in a first direction, the pivoting actuator arm causes an actuator cam to contact and engage the second cutting insert holder so that it is withdrawn while the first cutting insert forms a cut in the work surface. When the tool holder is displaced along the work surface in a second direction opposite the first direction, the pivoting actuator arm causes the actuator cam to contact and engage the first cutting insert holder so that it is withdrawn while the second cutting insert forms a cut in the work surface.

A method for cutting a groove of a predetermined groove width in a work piece, including the steps of providing a metallic work piece having a peripheral surface; providing a grooving tool including a blade portion having a constant or substantially constant blade width, and an insert having a maximum insert width defined by a main cutting edge; selecting the insert width to be greater than the blade width; connecting the grooving tool to a machine interface of a machine tool; rotating the work piece about a rotational axis thereof in a rotational direction; and cutting a groove in the work piece by moving the tool in a feed direction towards the rotational axis of the work piece, such that the groove width is equal to or substantially equal to the insert width and such that a tangential cutting force is directed towards or substantially towards the machine interface.

An exemplary hand-held, power operated rotary knife dermatome comprises a blade housing assembly and a depth gauge assembly. The blade housing assembly includes an annular blade housing and a blade lock ring for rotatably supporting an annular rotary knife blade. The annular blade housing includes a shield extending radially inwardly from a blade receiving body and including an inner wall defining a tissue directing surface, the tissue directing surface including a first tissue guide surface extending upwardly from a lower end of the shield, the first tissue guide surface extending substantially parallel to the blade housing axially extending center line. The blade receiving body includes an annular blade channel extending axially upwardly from a lower surface of the blade receiving body, a bearing surface axially spaced from a lower surface of the blade receiving body, and a threaded portion formed on the outer surface of the annular blade housing.

An indexable cutting insert has a central mounting portion and two cutting portions. The central mounting portion has opposing upper and lower surfaces. The lower surface has two abutment elements associated therewith, each abutment element having two diverging abutment surfaces forming two abutment angles. The two cutting portions extend away from the central mounting portion, have distal cutting edges, and are entirely located in diagonally opposite imaginary quadrants of four quadrants defined by two mutually perpendicular quadrant planes. Two abutment bisector planes bisecting the two abutment angles and one of the quadrant planes are parallel or coincident. In a top view, the two cutting portions extend away from the central mounting portion in opposite directions. Two cutting bisector lines parallel to the two directions and bisecting the two cutting edges are mutually offset. A cutting tool has an insert holder and the cutting insert removably retained therein.

A method for machining ribs or grooves on a workpiece such as a shaft or an air or gas axial bearing intended to be rotated about a longitudinal axis of a centrifugal compressor. All of the ribs or grooves are obtained at once by the machining tool on a workpiece portion driven such that it rotates, by moving the workpiece or the tool holder in a longitudinal machining direction, the machining tool moving back and forth with a machining position in contact with the workpiece and a position wherein it is not in contact with the workpiece from the start to the end of the workpiece portion. The back-and-forth movements of the machining tool are synchronised with the sinusoidal program set up in the machining unit, as well as with the desired, programmed arrangement of the ribs or grooves to be produced on the workpiece portion.

A motorized drapery system having an elongated rotating drive element that has a non-circular cross-sectional shape such as square, rectangular, trapezoidal, cross shaped or any other non-circular shape that is twisted. In one arrangement the drive element is twisted in one direction along its entire length. In another arrangement the drive element is twisted in one direction in a first section and twisted in an opposite direction in a second section thereby providing a center opening/center closing drapery. A plurality of rings are positioned around the drive element including at least one driver ring that includes a feature that connects to the drive element and is configured to facilitate movement along the drive element, and a plurality of idler rings that are configured to slide along the drive element. A curtain is connected to the rings and opens and closes as the rings move along the drive element.

A machining apparatus machines a surface of a workpiece by feeding, relative to the workpiece, a cutting tool having a plurality of cutting edges A to D with tips of the cutting edges A to D arranged at equal intervals. The machining apparatus performs a cutting process of cutting the surface of the workpiece with the plurality of cutting edges A to D and a feeding process of feeding the cutting tool relative to the workpiece by a predetermined feed amount to form a plurality of grooves on the surface of the workpiece. The predetermined feed amount is set to a length that is not an integral multiple of the interval between the tips of cutting edges.

The proposed technology relates to an indexable cutting insert (10) for a cutting tool. The cutting insert (10) comprises: a first side surface (12) and an opposing second side surface (14), and a peripheral surface (16) extending between the first side surface (12) and the second side surface (14). The cutting portion (18) comprises a first cutting face (24) and an opposing second cutting face (26), a flank face (28) extending between the first cutting face (24) and the second cutting face (26), a first cutting edge (20) between the first cutting face (24) and the flank face (28), and a second cutting edge (22) between the second cutting face (26) and the flank face (28). The cutting portion (18) is bisected by a first plane (AA′) transverse to the first side surface (12) and the cutting portion (18) has a biconcave cross-section transverse to the first plane (AA′).

An indexable cutting insert has a central mounting portion and two cutting portions. The central mounting portion has opposing upper and lower surfaces. The lower surface has two abutment elements associated therewith, each abutment element having two diverging abutment surfaces forming two abutment angles. The two cutting portions extend away from the central mounting portion, have distal cutting edges, and are entirely located in diagonally opposite imaginary quadrants of four quadrants defined by two mutually perpendicular quadrant planes. Two abutment bisector planes bisecting the two abutment angles and one of the quadrant planes are parallel or coincident. In a top view, the two cutting portions extend away from the central mounting portion in opposite directions. Two cutting bisector lines parallel to the two directions and bisecting the two cutting edges are mutually offset. A cutting tool has an insert holder and the cutting insert removably retained therein.