Abstract: A crankshaft assembly for a vehicle, a method of operating a crankshaft assembly, and a method of manufacturing a crankshaft assembly. The crankshaft assembly includes a crankshaft, a first pin bearing journal and a main journal, an oil passage having a main passage wall, the oil passage extending from the first pin bearing journal to or through the main bearing journal, a crankpin exit hole located in the main passage wall, and a blocking element positioned in the oil passage, wherein the blocking element is located in a radially outward position with respect to the crankpin exit hole.

Abstract: The present disclosure relates to grinding apparatus for grinding the hard metal inserts of rock drill bits, said grinding apparatus having said grinding machine equipped with a grinding cup driven by a motor to rotate about its longitudinal axis wherein the support system comprises an arm or lever system to control vertical movement of the grinding machine and means to provide grinding pressure, wherein the means to provide grinding pressure may be a linear actuator and load cell assembly pivotally connected to the arm or lever system.

Abstract: Stub shaft conveyor pulleys that may be used as a tail pulley and/or head pulley in a belt conveyor system are disclosed. The conveyor pulley includes first and second stub shaft assemblies connected to a center tube. Each stub shaft assembly includes an inner bearing and an outer bearing. In some embodiments, the outer bearing has a diameter larger than the inner bearing. Alternatively or in addition, the inner bearing may be within the center tube and the outer bearing may be exterior to the center tube.

Abstract: A method for milling a blank in the production of a turbine blade which in the final state has at least one blade root for fastening to a carrier and also an adjoining blade body extending in the longitudinal direction includes clamping the blank on its root side in a mount and machining the blank with a milling cutter. Machining the blank includes moving the milling cutter in an advancing direction for roughing machining while superimposing a circular movement as per a trochoidal milling method.

Abstract: Methods and devices for milling a channel-shaped cavity by a five-axis computer numerical control (CNC) machine by selecting a workpiece to be machined, determining cutting tool flow along the channel-shaped cavity, determining cutting tool in-depth penetration, determining a trochoid path, and determining auxiliary movements.

Abstract: A piston pin hole boring system and method of forming pin holes therewith includes fixing a piston to a fixture supported by a slide member. Then, rotating a cutting member about a first axis and moving the slide member with the fixture thereon toward the cutting member along the first axis and bringing the piston into cutting contact with the cutting member. Further, moving the fixture along second and third axes, each extending transversely to the first axis and machining the desired pin hole contours in the piston with the cutting member.

Abstract: A coping apparatus that performs a cope cut of varying diameters and angles on varying sizes, diameters, and types of materials without having to change the diameter of the cutting tool. The apparatus comprises a table with a clamp, a cylindrical housing with an aperture pivotally mounted to the table, a motor, a tool, and a yoke assembly. The yoke assembly is rotatably received within the housing and comprises a upper disc with a channel, a lower disc with a channel, a upper arm, a lower arm, a connector, and a handle. The arms are received in the channels of the upper and lower discs and moveable in a direction radial to the rotation of the discs. The motor is mounted to the lower arm and turns a spindle and the tool. Upon manipulation of the handle, the tool is plunged into the material to make the cut.

Abstract: A tool stocker includes main stockers for holding a plurality of tools detachably mounted on a main spindle for machining a workpiece, an auxiliary stocker for holding and transferring tools to and from the main stockers, and a tool transfer mechanism for transferring tools between the main stockers and the auxiliary stocker. The auxiliary stocker includes a plurality of tool pods for removably supporting the tools therein, a rail in sliding engagement with outer surfaces of the tool pods, a chain for moving the tool pods in sliding engagement with the rail, and a motor for actuating the chain. The rail has a recess defined therein in alignment with the tool transfer mechanism, such that the tools transferred by the tool transfer mechanism pass through the recess.

Abstract: A device for machining an electrical cable having a cylindrical part and a conical part adjoining the cylindrical part. The device includes a fixture arranged to receive the cable and to hold the cable in a fixed position, the fixture defines an elongated space for accommodating the cable, a tool for removing material from the cable including at least one cutter, and rotational guiding means for guiding a first rotation of the cutter about a longitudinal axis of the space. The cutter is elongated and the longitudinal axis of the cutter is arranged inclined with respect to the longitudinal axis of the space so that the angle between the longitudinal axes of the cutter and the space is between 10 and 80 degrees. The device further includes drive means for providing a second rotation of the cutter about a rotational axis through the tool in order to cause the machining.

Abstract: A combination end milling/drilling/reaming cutting tool includes an end milling portion, a drilling portion, and a reaming portion. The cutting tool also includes a neck portion between the end milling portion and the drilling portion, and a clearance neck portion between a shank and the reaming portion. A method of machining a workpiece using the combination end milling/drilling/reaming cutting tool is also disclosed.

Abstract: An eccentric rotation drive mechanism which is rotatably contained in a first slide container is provided with an outer cylinder, an internal cylinder which is housed at eccentric position thereof and a first air motor contained therein. One end of a rotation shaft portion, that is, a shaft of the first air motor is fastened to a hole making tool, the other end of which is coupled to the end surface of the outer cylinder through a first reduction device. The rotation of the air motor makes the hole making tool rotate and revolve and simultaneously the rotation of a second air motor mounted outside of a casing is transmitted to a ball screw through a rotation transmission device inside of a second slide container to advance and retreat a feed drive mechanism so as to machine a hole in a workpiece.

Abstract: A tool may be used to form an engine cylinder bore in a compacted graphite iron workpiece using helical interpolation. The tool may be rotated about a first axis while orbiting about a second axis that is parallel to the first axis. While rotating and orbiting, the tool may be advanced into the workpiece. This helical interpolation may be used to successively engage cutting or honing elements of the tool with the workpiece. The elements may thereby be permitted to cool between each successive engagement, which may reduce wear on the tool. Various operating parameters associated with the process may have certain relationships that may be exploited in certain ways to obtain ideal results. For instance, a helical interpolation process may be used to perform an act of rough cutting on the workpiece and finish honing on the workpiece, without having to perform an intermediary step of semi-finish boring.

Abstract: To increase precision in straightness on a journal thrust surface relative to an outer peripheral surface of a journal in a crankshaft, a control system is provided for controlling movement of a cutter in axial directions by running a control program transferred from an automatic programming apparatus. The automatic programming apparatus corrects machining data on the basis of data for correcting the straightness gained through a comparison between results of a measurement of machining dimensions of the journal thrust surface in the workpiece on which a cutting process has been carried out and target machining dimensions for the journal thrust surface. A control program is prepared on the basis of the corrected machining data after correction of the machining data.

Abstract: An apparatus for drilling a workpiece has a shaft portion including a holder to hold a drilling tool rotating around a first axis. A reduction gear is connected to the shaft portion. A cylindrical member, including an outer cylinder and an inner cylinder, rotatably contains the shaft portion at an eccentric position. The cylindrical member is connected to the output shaft of the reduction gear and rotated around a second axis parallel to the first axis. A slide containing cylinder contains the shaft portion, the reduction gear and the cylindrical member. The slide containing cylinder has a sliding structure for axially moving the shaft portion, the reduction gear and the cylindrical member. A drilling tool is simultaneously rotated around the first axis, revolved around the second axis and is axially moved.

Abstract: An apparatus for aligning a machine tool with a target location on a structure. A machine plate positionable on the structure has a plate bushing providing a hole through the plate. The apparatus also includes a nosepiece for guiding a distal end of the tool through the plate bushing to the target location. The nosepiece has a collet configured to be moved at least partly through and sideward in the plate bushing to center the nosepiece on an element projecting from the structure at the target location. The nosepiece can be attached to the plate bushing to establish normality of the tool relative to the projecting element.

Abstract: Method and system for producing holes of various dimensions and configurations in a workpiece (42) using a portable orbital drilling machine (44), wherein said workpiece has attached thereto a template (10) with preformed guide holes (12-40) located in a pattern corresponding to the positions of the holes to be formed in the workpiece. Each guide hole (12-40) is provided with a readable information carrier (12i-40i) containing an identification of the respective guide hole. When fixating the drilling machine (44) in a guide hole, the latter is identified by a hole database (48) by sensing the respective information carrier. A control unit (50) associated with the hole database (48) controls the drilling machine (44) to perform a relevant hole-cutting process in the workpiece.

Abstract: The invention relates to an apparatus for cutting an oval hole in the wall of a pipe. The pipe secured to a baseplate (1) of the apparatus is cut for an oval hole by means of a tool (20) having its cutter head (24) rotated about its axis while it is driven along a circular path in relation to a carriage (2) of the apparatus. The carriage (2) is mounted on the baseplate (1) by way of linear runners (3). Adapted for rotation along with a drive pulley (4) of the tool (20) is a cogged wheel (10), which through the transmission of a cam lever (11) is adapted to drive a shaft (12) having its rotational motion transmitted on the one hand to drive a gear (22) and on the other hand to work the carriage (2) back and forth in relation to the baseplate (1), a round-trip displacement (2xa) being equal to a difference between the major axis and the minor axis of a desired ellipse.

Abstract: A mobile device for simultaneously cutting, chamfering and grooving a pipe. The device having a frame, at least one pipe collet-clamp attached to the frame and defining a principal axis, a split carriage rotatably mounted with respect to the frame about the axis and adjacent to the clamp(s), a router affixed to the split carriage and having a cutting-chamfering bit, a grooving router and a drive motor for rotating the carriage. The routers orbit around the pipe and simultaneously cuts the pipe into two chamfered pipes with grooves. A method is also provided for cutting through a pipe, chamfering the cut ends thereof and grooving the pipe.

Abstract: The casing cutter disclosed herein is useful for severing downhole tubulars and includes a body, a cutting head, cutting blades, and actuators for operating the cutting head and cutting blades. Cutting is accomplished by rotatingly actuating the cutting head with an associated motor, and then radially extending the cutting blades away from the cutting head. In one embodiment, the cutting head includes a cutting member that pivotally extends from the cutting head upon rotation of the cutting head. In another embodiment, cutting members extend from the cutting head due to centrifugal forces associated with rotating the cutting head.

Abstract: A mobile device for simultaneously cutting and chamfering a pipe is provided having a frame, at least one pipe collet-clamp attached to the frame and defining a principal axis, a split carriage rotatably mounted with respect to the frame about the axis and adjacent to the clamp(s), a router affixed to the split carriage and having a cutting-chamfering bit, and a drive motor for rotating the carriage. The router orbits around the pipe and simultaneously cuts it into two chamfered pipes. A method is also provided for cutting through a pipe and chamfering the cut ends thereof.

Abstract: Methods are disclosed for producing a hole in a work-piece having first and second layers of material. The first layer of material contains a full-sized hole through the first layer of material. The first layer of material is positioned adjacent the second layer of material. An orbital drill is secured to the first layer of material to position a cutting tool of the drill within the through-hole. During operation, when the cutting tool is used to cut a hole in the second layer of material, the alignment keeps the orbital drill stationary.

Abstract: An apparatus for aligning a machine tool with a target location on a structure. A machine plate positionable on the structure has a plate bushing providing a hole through the plate. The apparatus also includes a nosepiece for guiding a distal end of the tool through the plate bushing to the target location. The nosepiece has a collet configured to be moved at least partly through and sideward in the plate bushing to center the nosepiece on an element projecting from the structure at the target location. The nosepiece can be attached to the plate bushing to establish normality of the tool relative to the projecting element.

Abstract: In a machine tool arrangement comprising a machine tool component including a mounting structure for a work piece to be machined by a suitable metal cutting tool, a housing enclosing the machine tool component, a horizontal support beam is disposed above the housing and carries handling equipment for supplying work pieces from an adjacent loading area to the machine component for machining and returning the finished work pieces to the storage structure and an intermediate storage structure is disposed near the machine tool component for temporarily storing unfinished work pieces to be machined and finished work pieces after being machined.

Abstract: A telescopic safety shield device includes a carrier movably engaged onto a platform and having one or more guideways tilted relative to the platform, a tool rest movably engaged onto the guideways and moveable inclinedly relative to the carrier and the platform, and a telescopic shielding device having two or more casing members coupled between the platform and the tool rest for shielding the area between the platform and the tool rest, the casing members are pivotally coupled to the platform and the tool rest for allowing the casing members to be pivoted relative to the platform and the tool rest respectively and for preventing dirt or contaminant from entering into the areas between the platform and the tool rest.

Abstract: A two rotational and one translational parallel mechanism which comprises a holding bracket; a movable platform; and three branch joint assemblies of the same structure spatially and axis-symmetrically disposed between the holding bracket and the movable platform. Each branch joint assembly comprises a connecting rod, a linear guide, a driving device and a carriage. The linear guide and the driving device both are secured on the connecting rod. One end of the connecting rod is connected with the movable platform through a hinge having three rotational degrees of freedom. The carriage and the linear guide are connected with each other by a sliding joint, and the carriage is connected with the holding bracket by a hinge having one rotational degree of freedom.

Abstract: A method and apparatus for measuring a hole depth in a composite-material workpiece machined by a orbital cutting tool, including the steps of applying a low-level electric potential to an electrically insulated cutting tool having a cutting head with radial and axial cutting edges and with a predetermined axial length; determining a first zero reference position as the cutting tool initially contacts a first surface of the workpiece and closes an electric circuit through the grounded workpiece; and detecting a second reference position when the cutting head penetrates an opposite, second surface of the workpiece. The finished hole depth is determined by deducting the predetermined axial length of the cutting head from the total length of axial advancement from the first zero reference position to the second reference position. The orbital machining apparatus includes ceramic bearings electrically insulating the spindle and the cutting tool from surrounding components of the apparatus.

Abstract: A numerical control unit issues a sequence of instructions for causing a spindle of a cutter disk in a tool machine to perform successive straight displacements approximating a spiral of Archimedes, with a predetermined angle step from one point to the next, and issues one or more ADIS instructions for merging each of the straight displacements with the next. The spiral path is such that the cutter disk will progressively shave a chip of a predetermined thickness over several revolutions, until its cutting edge is near the intended groove bottom. The tool is then caused to follow a merging path leading to a final point lying on the intended groove bottom, and finally is caused to follow a full circular path coaxial to the bore starting from the final point.

Abstract: A tool chuck may include a chuck body that supports chuck jaws. The chuck body may define a longitudinal axis. A driven gear may be mounted for rotation on the chuck body. The rotational axis of the driven gear may be parallel to the longitudinal axis of the chuck body. A nutating gear may be provided on the chuck body. The nutating gear may be nutatable about the chuck body to rotationally drive the driven gear relative to the chuck body so that the chuck jaws move along the longitudinal axis of the chuck body.

Abstract: A numerical control unit issues a sequence of instructions for causing a spindle of a cutter disk in a tool machine to perform successive straight displacements approximating a spiral of Archimedes, with a predetermined angle step from one point to the next, and issues one or more ADIS instructions for merging each of the straight displacements with the next. The spiral path is such that the cutter disk will progressively shave a chip of a predetermined thickness over several revolutions, until its cutting edge is near the intended groove bottom. The tool is then caused to follow a merging path leading to a final point lying on the intended groove bottom, and finally is caused to follow a full circular path coaxial to the bore starting from the final point.

Abstract: A machine tool is provided, in particular for the synchronous machining of workpieces. The tool includes two or more spindle units (2, 3), which run parallel in a machining unit and are designed to hold tools and repositioning devices for the precise adjustment of the position of the spindle units (2, 3) in relation to one another, preferably in all three directions x, y and z of the orthogonal co-ordinate system in the machining unit (4). The repositioning devices for displacing at least one of the spindle units (2, 3), at least in an x and/or y direction, include an eccentric bush (5, 6), which can be rotated about a central shaft (B1, B2) and locked and in which the spindle units (2, 3) are mounted eccentrically, parallel to the central shaft (B1, B2).

Abstract: An orbital machining apparatus for producing a workpiece hole with a cutting tool, including: a first actuator for rotating the tool about its longitudinal center axis during the machining of the hole; a second actuator for moving the tool in an axial feed direction substantially parallel to the tool axis; a third actuator for rotating the cutting tool about a principal axis; and a radial offset mechanism. The third actuator includes a rotating drive driven by a motor, a carrier ring connected to and rotated by the drive by two opposed, radial drive pins. The ring performs a radial sliding movement relative to the drive while being rotated thereby. Two opposed, radial carrier guide shafts circumferentially spaced 90° from the drive pins and connecting the ring and an inner cylindrical eccentric body such that the latter may perform a radial sliding movement relative to the ring while being rotated thereby.

Abstract: A device for the temporary fixation of a portable cutting machine to a template for making holes and/or recesses in a workpiece including a guide sleeve and a tensioning unit. The guide sleeve includes a tubular hub with an outer diameter corresponding to an inner diameter of an aperture in the template, a forward end of the hub having radially extending lugs configured and located so as to match corresponding recesses in the aperture during the insertion of the guide sleeve therein and to obtain a locking engagement with an inner surface of the template after a partial rotation of the guide sleeve relative to the template. A rearward end of the hub has a tubular adapter socket that is mounted to a nose portion of the cutting machine. The tensioning unit is mounted to the adapter socket for axial displacement relative thereto and having a forward end surface for engagement with an outer surface of the template.

Abstract: A machine for machining workpieces has at least one milling tool with an internal cutter. The machine is provided with a first guide system and a second guide system parallel to the first guide system. The first guide system has at least one compound slide having a slide part, wherein the at least one compound slide is moveable in a longitudinal direction of the first guide system and wherein the slide part is moveable transversely to the longitudinal direction. A milling tool is secured on the slide part. The first and second guide systems have sliding guides or roller bearing guides. The at least one compound slide has a transverse guide system and the slide part is guided on the transverse guide system.

Abstract: The transmission of the rotational movement to the driving pinion of the carriage is provided by: a first gear train with a cage mounted so that it can rotate about the axial shaft and the crown wheel of which meshes with a pinion fitted onto the shaft of an electric motor carried by the body, this train carrying at least two superposed planet pinions and meshing, in the case of the upper one, with a set of teeth formed around the axial shaft and, in the case of the lower one, with an output sun gear, a second train, the sun gear of which is secured to the output sun gear of the first train and meshes with the upper planet pinion of at least one set of superposed planet pinions which are mounted so that they are free to rotate in a continuation of the body, the lower planet pinion meshing with a set of teeth which, formed on the driving pinion of the carriage, is distinct from the set of teeth that collaborates with the rack of this carriage, these two sun gears having ratios which are other than 1 and in

Abstract: A fixation device for positioning a rotating machine tool onto a template, the template having at least one hole and at least one locating pin. The fixation device includes a housing with a housing tool end and a housing template end, a seat located on the housing tool end for coupling with the rotating machine tool, and a clamping mechanism disposed at least partially at the housing template end for coupling with at least one locating pin.

Abstract: A hole of a hole size is cut in a composite material workpiece by selecting a milling cutter having an effective cutter size less than the hole size, mounting the composite material workpiece in operable relation to the milling cutter, rotating the milling cutter about an axis of rotation, and advancing the milling cutter longitudinally into the composite material workpiece parallel to the axis of rotation at a rate of longitudinal advance, while laterally moving the milling cutter perpendicular to the axis of rotation to interpolate the hole. The rate of longitudinal advance is controlled such that the hole remains substantially a flat-bottomed hole as it is cut. The composite material workpiece is desirably affixed to a backing fixture with an adhesive material during the cutting of the hole.

Abstract: A method and apparatus for producing conical holes in a workpiece by using a substantially cylindrical cutting tool having a cutting head diameter essentially smaller than the top and bottom diameter of the hole to be formed. The method comprises the steps of positioning the longitudinal center axis of the cutting tool at an angle, which is offset from a normal to a flat surface of the workpiece such that the inclination of the longitudinal axis of the cutting tool substantially corresponds to the desired inclination of the wall of the conical hole to be formed, rotating the cutting tool about its longitudinal center axis, moving the cutting tool in a circular path about a principal axis corresponding to the longitudinal center axis of the hole to be machined, and feeding the cutting tool in its longitudinal direction towards and into the workpiece.

Abstract: A hand tool apparatus uses a cutting tool with a first width and a tool axis to machine a hole in an object. The hole has a second width at least as large as the first width of the cutting tool. The tool axis passes through a predetermined point on a surface of the object. The apparatus includes an actuating assembly including a housing. The housing contains an axial feed mechanism configured for moving the cutting tool in an axial direction, a spindle motor configured for rotating the cutting tool about the tool axis, and a radial offset mechanism. The radial offset mechanism is configured for moving the axial feed mechanism in a radial direction such that the tool axis is offset from a principal axis. A motor is configured for rotating said axial feed mechanism and the cutting tool about the principal axis.

Abstract: A milling method is provided for the manufacture of components composed of difficult-to-cut materials for turbomachines, aircraft and spacecraft by producing recesses with one or more side walls. An end milling cutter which cuts at the circumference and at the tip and has a tip contour which is rounded towards the circumference is used as the rotating milling tool. In addition to rotation about its axis, the milling tool performs an eccentric orbiting motion about an orbital axis spaced apart from its axis. The opposite senses of rotation lead to downcut milling, and the orbital axis performs a translational advance motion on a straight and/or curved path transversely to its longitudinal direction, with or without a swivelling motion.

Abstract: The invention refers to a tool (1), a machine tool, and a method for cutting machining of a workpiece. The tool includes a mounting portion (5) for mounting of the tool in the machine tool, a tool shaft (7), which has a first inner end (7?), connected to the mounting portion (5), a longitudinal center axis (a), which extends through the mounting portion and the tool shaft, and a main cutting edge (9) on the tool shaft. The main cutting edge (9) has an extension in an axial direction along an imaginary envelope surface, which is concentric to the center axis (a) and located radially outside an outer periphery surface of the tool shaft (7). The main cutting edge (9) is arranged to permit cutting engagement with said workpiece when the tool is rotated around the longitudinal center axis.

Abstract: A machining apparatus for machining a workpiece by rotating and revolving either the workpiece or a tool 1 to contact with each other. The machining apparatus comprises rotation/revolution ratio setting motors M1 and M3 for setting a ratio of a number of rotations to a number of revolutions of the workpiece or the tool 1, to a numerical value having a fraction below a decimal point, by changing the number of revolutions. The workpiece is machined by setting the number of revolutions and the number of rotations at the ratio.

Abstract: A machine for machining workpieces has at least one milling tool with an internal cutter. The machine is provided with a first guide system and a second guide system parallel to the first guide system. The first guide system has at least one compound slide having a slide part, wherein the at least one compound slide is moveable in a longitudinal direction of the first guide system and wherein the slide part is moveable transversely to the longitudinal direction. A milling tool is secured on the slide part. The first and second guide systems have sliding guides or roller bearing guides. The at least one compound slide has a transverse guide system and the slide part is guided on the transverse guide system.

Abstract: A method and cutting tool for producing a hole or a recess in a workpiece which includes flat or curved sheets of fiber-reinforced composite material, metal or combinations thereof. The cutting tool has a shaft with a longitudinal axis and an axial cutting surface and at least one cutting edge disposed on the axial cutting surface and extending radially from the longitudinal axis with a gap between the radial inner extent of the cutting edge and the longitudinal axis. The method of use includes rotating the cutting tool about its longitudinal axis and also translating the cutting tool during rotation.

Abstract: A hand tool apparatus uses a cutting tool with a first width and a tool axis to machine a hole in an object. The hole has a second width at least as large as the first width of the cutting tool. The apparatus includes a housing, a spindle unit in the housing for rotating the cutting tool and an orbital drive for rotating the spindle unit. An axial feed mechanism moves the orbital drive and the spindle unit jointly either toward or away from the object being machined.

Abstract: A hand tool apparatus uses a cutting tool with a first width and a tool axis to machine a hole in an object. The hole has a second width at least as large as the first width of the cutting tool. The tool axis passes through a predetermined point on a surface of the object. The apparatus includes an actuating assembly including a housing. The housing contains an axial feed mechanism configured for moving the cutting tool in an axial direction, a spindle motor configured for rotating the cutting tool about the tool axis, and a radial offset mechanism. The radial offset mechanism is configured for moving the cutting tool such that the tool axis is offset from a principal axis. A motor is configured for rotating the axial feed mechanism and the cutting tool about the principal axis.

Abstract: An orbital machining apparatus for producing a hole in a workpiece using a cutting tool and including a first actuator for rotating the cutting tool about its longitudinal center axis, a second actuator for moving the cutting tool in an axial feed direction, a third actuator for rotating the cutting tool about a principal axis and a radial offset mechanism. The radial offset mechanism includes an inner cylindrical body having an eccentric cylindrical hole and which supports a spindle unit, the inner cylindrical body radially supported in an eccentric cylindrical hole of an outer cylindrical body to adjust the radial distance of the cutting tool longitudinal center axis from the principal axis. The third actuator includes first and second motors which rotate the outer and inner cylindrical bodies, respectively, in synchronism to maintain a mutual rotary position thereof to keep a cutting tool radial offset position unchanged during operation.

Abstract: For an orbit boring to be performed by a tool (10) in an orbital motion along an orbit (A), a permissible range of an acceleration (a) of the orbital motion is provided to meet a criterion of a machining precision of the orbit boring, and the acceleration (a) is controlled to be suppressed within the permissible range.

Abstract: A process for the metal-removing machining of a workpiece, where a disc-shaped external milling cutter is provided having cutting edges positioned on its outer circumference, the workpiece is rotated, and peripheral surfaces of the workpiece are machined with the milling cutter, by rotating the milling cutter to have a cutting speed of at least 180 m/min when roughing and at least 200 m/min when finishing, and a chip thickness of between 0.05-0.5 mm.

Abstract: A hand tool apparatus uses a cutting tool with a first width and a tool axis to machine a hole in an object. The hole has a second width at least as large as the first width of the cutting tool. The apparatus includes a housing, a spindle unit in the housing for rotating the cutting tool and an orbital drive for rotating the spindle unit. An axial feed mechanism moves the orbital drive and the spindle unit jointly either toward or away from the object being machined.

Abstract: An apparatus for drilling a workpiece has a shaft portion including a holder to hold a drilling tool rotating around a first axis. A reduction gear is connected to the shaft portion. A cylindrical member, including an outer cylinder and an inner cylinder, rotatably contains the shaft portion at an eccentric position. The cylindrical member is connected to the output shaft of the reduction gear and rotated around a second axis parallel to the first axis. A slide containing cylinder contains the shaft portion, the reduction gear and the cylindrical member. The slide containing cylinder has a sliding structure for axially moving the shaft portion, the reduction gear and the cylindrical member. A drilling tool is simultaneously rotated around the first axis, revolved around the second axis and is axially moved.