Abstract: A method for manufacturing a heat transfer member comprises the step of subjecting a material to be worked, which is made of a metallic thin sheet, to a press forming utilizing a press-forming device to form a heat transfer member for a heat exchanger. The heat transfer member has on at least one portion thereof a heat transfer face that has opposite surfaces, which are to be come into contact with heat exchange fluids, respectively. The press-forming device comprises a pair of main molds for forming the heat transfer face on the material, which is to be conveyed in a single feeding direction, and two pairs of first auxiliary molds, which are disposed on upstream and downstream sides of the pair of main molds in the feeding direction of the material, so as to be exchangeable.

Abstract: The present invention relates to a machine tool (11) for machining a large-sized workpiece (89) such as aircraft parts mounted on a workpiece mounting table (99), by moving a spindle having a tool mounted thereon in directions along the X-axis, the Y-axis and the Z-axis. The machine tool (11) can provide a highly efficient, high-speed and highly precise machining for a large-sized workpiece (89) and solve a problem of a compact installation area. In order to solve this problem, according to the present invention, a workpiece support structure (15) is disposed in opposed relation to a spindle support structure (13) which a spindle head (73) movable in the directions along the X-axis, the Y-axis and the Z-axis. The workpiece mounting table (99) of the workpiece support structure (15) is provided with pallet securing means on two opposed pallet mounting surfaces thereof and is supported to allow for rotational indexing about a horizontal axis extending in the direction along the X-axis.

Abstract: Device for putting polyethylene cladding on a galvanized steel plate, wherein a galvanized steel plate unroller from unroller is passed through a plate press, an ultrasonic cleaner, a dryer, an intermediate frequency heater, and a roll press in succession, and polyethylene sheets unrolling from one pair of sheet unrollers are welded on opposite sides of the galvanized steel plate, and rolled on a sheet roller, thereby automatically putting polyethylene cladding on the galvanized steel plate, to improve workability and productivity.

Abstract: The present invention concerns an apparatus and method for manufacturing an automotive beam for use as a beam in structural components of automobiles with significant improvements in terms of torsional rigidity and yield strength. The beam improves the overall safety of passengers and maintains the simplicity of the manufacturing process. The apparatus (1) for manufacturing roll formed profile beams comprises a plurality of material dispensers (2,6), a first set of rollers (5), a second set of rollers (11), a first welding station (10) mounted between the two sets of rollers (5, 11) and a second welding station (12) at the outlet of the second set of rollers (11). The method of manufacturing roll formed profile beams comprises the steps of roll forming a first profile element followed by roll forming a second profile element enclosing the first profile element and forming a closed profile beam having an internal support structure.

Abstract: A flexible manufacturing line and manufacturing process employs an overhead gantry system to transfer fixtured workpieces between machining stations served by the gantry system. The machining stations include CNC machines, turret cells, and/or dedicated machines which receive the fixtured workpieces through top-entry openings. The invention provides flexibility and adaptability to variation, improved maintenance of reference position on the fixture during manufacture, improved accessibility to machining stations during operation, and increased safety.

Abstract: A machining apparatus has a lower housing part, an upper housing part having a lower side, and a plurality of support posts fixed to the upper and lower parts and holding the upper part fixedly at a spacing above the lower part. A tool holder displaceable parallel to a horizontal tool axis on the lower side of the upper housing part carries a chuck rotatable about the tool axis and can hold a machining tool. A supply station on the lower part offset horizontally perpendicular to the tool axis from the tool holder is can hold a plurality of the workpieces. A cross slide connected between the upper housing part and a workpiece chuck displaces the workpiece chuck in a horizontal direction perpendicular to the tool axis and in a vertical direction to displace a workpiece between the station and a position aligned on the tool axis with the tool chuck.

Abstract: Method and apparatus providing a tool turret for a machine tool with at least one motor-driven tool that is suitable for machining of wavy or tubular workpieces. The transport of the workpieces from one machining station to the next is effected in a simpler, more reliable, and less expensive fashion, because the machine tool has a tool turret that includes a gripping element for taking hold of, transporting, and positioning workpieces, rather than using an additional tool.

Abstract: A method for forming a shelf is presented herein and includes shearing a straightened metal coil with a shearing mechanism and forming a sheared portion having a first length. The sheared portion has a first width and opposing ends that define a shelf width. The shearing mechanism is incorporated into a punch. The sheared portion is fed into a rollform mill set to receive sheared portions having the first width. The sheared portion is formed to have a predetermined depth. The sheared portion is fed into a press brake and at least one of the opposing ends of the sheared portion is bent with the press brake. The sheared portion is then ejected from the press brake.

Abstract: A machine tool in which a plurality of machining positions is orbited by a work spindle unit carrying a workpiece and capable of radial displacement relative to the central axis of rotation. The work spindle unit may be one of one or more such units mounted upon a bridge element angularly displaceable about that axis.

Abstract: A lathe (10) includes a support structure (12) which supports a magazine (14) in a substantially vertical operative orientation. The magazine (14) is rotatably supported in a carriage (24). The magazine (14) is a multi-spindle magazine and supports a plurality of workpieces. A workstation head (40) is mounted on the housing (18). The workstation head defines a plurality of workstations (46). Each workstation head includes a plurality of working tools.

Abstract: A process for the manufacturing of longitudinal profiles such and tongue and groove on boards wherein the process includes the steps; a) Moulding a substantial part of the profile cross-section by means of milling with a milling tool. b) Fine moulding undercuts in at least the groove of the board by means of broaching utilising at least one broaching tool.

Abstract: The apparatus and method for application of a protective covering to an unprotected paper roll in locations without major paper handling equipment is described to provide an inexpensive and portable system for paper roll refurbishing. Apparatus used in the present invention includes: an apparatus for holding the body wrapper supply roll and measuring the unrolled wrapper to a desired length; an apparatus for rewinding and cutting individual wrappers for transport to the point of use; an apparatus for applying the wrappers to the paper roll; an apparatus for transporting the rolls from the resizing area to the wrapping area; and an apparatus for crimping the body wrap over the end of the roll to retain the header; an apparatus for retention of the headers and caps under pressure during curing of the retaining adhesive.

Abstract: A machining center capable of fabricating and machining both ends of a work piece, such as a patio door sill. The machining center comprises two heads, each of which comprise several machining devices and tools which can perform the necessary machining operations on each end of the sill. Each head is configured to perform a cope, a back weep, a front weep, a screen weep on the sill, and to drill two holes in the sill. The heads are slidably mounted on rails so that the heads are able to travel in the direction of the length of the sill.

Abstract: A system for processing elongate workpieces. The system consists of a first machining unit for performing a first processing operation on an elongate workpiece that is situated at a first location and a second machining unit for performing a second processing operation on an elongate workpiece that is situated at a second location that is vertically spaced from the first location. The system further consists of a first supply unit on which a plurality of elongate workpieces can be placed in a stored position. A transfer assembly engages an elongate workpiece in a stored position and selectively delivers an elongate workpiece engaged by the transfer assembly to one of the first and second locations.

Abstract: A method of machining a plurality of workpieces in an unmanned manner, including the steps of holding, with a jig, a first one of the workpieces, attaching the jig holding the first workpiece, to a workpiece holding device of at least one machining device, so that the first workpiece is machined by the machining device, detaching, after the machining of the first workpiece, the jig holding the first workpiece, from the workpiece holding device, removing the first workpiece from the jig, and holding, with the jig, a second one of the workpieces, and repeating the attaching step, the detaching step, and removing step.

Abstract: An automatic production and assembly machine focuses on the fact that each unit is provided with coding indicating at least the type of the specific function unit. The coding is transmitted via data transmission existing between the individual function unit and a central control unit. The coding makes possible continuous checking of the control program, such that certain program sequences for certain workstations are only executed when the coding of these workstations agrees with the respective program sequence. A number of other important functions are monitored, corrected and made to coincide with the central programming.

Abstract: The invention deals with a machining installation comprising at least one transfer path which conveys a workpiece to several machining stations. In the machining stations at least one tool spindle is provided. The workpiece is moved while being machined by the tool spindles.

Abstract: A flexible manufacturing system including at least one module, a operational unit mounted to said at least one module and a local controller operatively connected to the operational unit. The local controller is adapted to control the operational unit. The at least one module and the local controller together are capable of operating in a standalone operation or of integration into a flexible manufacturing system. The local controller is further adapted to receive a reference signal from the flexible manufacturing system and to synchronize the operational unit to the flexible manufacturing system when the at least one module is connected to the flexible manufacturing line.

Abstract: A substantial apparatus width along a board carrying direction of an electronic component placing apparatus for placing electronic components on a board having a length L along the board carrying direction is a total dimension 4L+SL of 4L as a length with which each of two boards corresponding to a plurality of head units can be positioned at each component placement position and a board retreat position corresponding to each placement position can be secured and SL as a space for positioning a board stop mechanism at each placement position and each board retreat position, which is not less than 450 mm and not more than 1000 mm.

Abstract: A molding machine for machining workpieces of wood or plastic material has a transport path for transporting workpieces in a transport direction and adjustable spindles arranged sequentially in the transport direction on the transport path. Tools are fixedly connected on the spindles. Adjusting elements are drivingly connected to the spindles. First indicator devices are coupled to the adjusting elements and indicate a position of the spindles relative to a reference point of the machine, respectively. At least one data storage device is connected to the indicator devices and configured to save position data of the spindles and to allow retrieval of the position data of the spindles.

Abstract: A plurality of thermoplastic tubular segments having substantially equal lengths are arranged in horizontal side-by-side relationship with the respective ends of the tubular segments aligned in a generally common plane. Small portions of the respective ends of the tubes are cut by a thermal cutting device which simultaneously fuses the ends of the tubes to produce a consolidated unitary structure having a thickness defined by the distance between the fused ends of the tubular segments. The consolidated unitary structure is then rotated to a horizontal position, with the tubular segments vertically oriented, and cut along at least one horizontal plane to produce fused cores having a thickness defined by the vertical position of a horizontally disposed thermal cutting device.

Abstract: A transfer line apparatus for performing multiple machining operations on each of a plurality of workpieces in a transfer line. The apparatus includes a plurality of different kinds of machining units disposed at respective machining stations along a transfer path. A workpiece transporter moves workpieces along the transfer path to position each of the workpieces at each of the machining stations and allow each of the machining units to machine each of the workpieces as the workpieces move along the transfer path. A controller connected to the machining units responds to an inspection command by causing all machining units downstream from a designated machining unit along the transfer path to allow a workpiece selected for inspection to pass by without being machined by the downstream units. This allows the workpiece to be inspected in a form that the remaining machining units have not altered.

Abstract: A railroad frog positioning and reconditioning table has an I-beam structure designed to support one or more frogs to enable welding repair of defective running surfaces. After defects are repaired with welding material, a portable frog milling machine table is attached to the frog table for positioning of a milling head over the frog which remains on the frog table. The milling head is connected to a support base that traverses the angular iron framework forming the milling machine table through guided sliding movement powered by a rack and pinion drive mechanism. Thus, the milling head cuts the running surface to original profile and an end mill cutting head cuts the frog flange ways to proper profile. The milling head cutting path is movable into straight and angularly offset positions to enable proper contouring.

Abstract: A transfer line apparatus for performing multiple machining operations on each of a plurality of workpieces in a transfer line. The apparatus includes a plurality of different kinds of machining units disposed at respective machining stations along a transfer path. A workpiece transporter moves workpieces along the transfer path to position each of the workpieces at each of the machining stations and allow each of the machining units to machine each of the workpieces as the workpieces move along the transfer path. A controller connected to the machining units responds to an inspection command by causing all machining units downstream from a designated machining unit along the transfer path to allow a workpiece selected for inspection to pass by without being machined by the downstream units. This allows the workpiece to be inspected in a form that the remaining machining units have not altered.

Abstract: The present invention relates to a method of covering a wire using a transport carrier and a heating system. The present invention makes the workability of a transport carrier compatible with the maintenance of positioning accuracy and imparts a general-purpose property. An electric wire-hanging member is provided on which a plurality of bundles of electric wires are hung in a parallel. A holder is provided for retaining the electric wire-connecting parts which are formed in bundles of electric wires on the electric wire-hanging member. Further, an electric wire sandwiching system for regulating the retention of at least the electric wire-connecting parts side of the bundles of electric wires which are hung on the electric wire-hanging member and for releasably retaining the connected bundles of electric wires.

Abstract: A removable plug for an air vent in a mold includes an annular bushing and an annular insert. The annular bushing includes a central bore preferably of about 0.8 mm. The annular insert includes a central bore preferably of about 0.1 mm to 0.4 mm. The annular insert is snugly fitted into the central bore of the annular bushing. A mold including the plug and a method for making the mold are also described.

Abstract: Automated equipment mounts heat sinks on printed circuit boards. First heat sinks, semiconductor modules and second heat sinks are consecutively seated on a plurality of built-up pads as the built-up pads move from station to station around a built-up pad conveyer. Rivets are mounted in a first heat sink and inserted through holes in a semiconductor module and a second heat sink when seating the semiconductor module and the second heat sink. Working the rivets fixes the first heat sink, the semiconductor module and the second heat sink permanently, and thereby forms a semiconductor product. After that, a label is attached on the semiconductor product and the riveting quality and the labeling quality of the semiconductor product are inspected.

Abstract: A system for processing elongate workpieces. The system consists of a first machining unit for performing a first processing operation on an elongate workpiece that is situated at a first location and a second machining unit for performing a second processing operation on an elongate workpiece that is situated at a second location that is vertically spaced from the first location. The system further consists of a first supply unit on which a plurality of elongate workpieces can be placed in a stored position. A transfer assembly engages an elongate workpiece in a stored position and selectively delivers an elongate a workpiece engaged by the transfer assembly to one of the first and second locations.

Abstract: The combination of at least a first base, a first machine tool assembly placed in an operative position on the at least first base, and a second machine tool assembly placed in an operative position on the at least first base above the first machine tool assembly.

Abstract: In a coiling apparatus for measuring cutting and optionally marking a succession of lengths of an elongate flexible such as wire or cable, the leading edge of each of the elements are clamped in the same angular position in a rotary coiling assembly.

Abstract: Component placement machine with a frame (1) and a transport device (2) for transporting printed circuit boards (3) in an X-direction, which transport device is provided with a transport belt (9) having an outer surface (13) on which printed circuit boards (3) are positioned. During the transport of printed circuit boards (3) as well as during the placement of components (6) on the printed circuit boards (3) an edge portion (12) of the printed circuit board which extends in the X-direction is retained between the outer surface (13) of the transport belt (9) and a contact surface (11) of the frame (1). The outer surface (13) of the transport belt has a relatively high coefficient of friction in contact with said edge portion (12) of the printed circuit board, whereas said contact surface (11) of the frame has a relatively low coefficient of friction in contact with said edge portion (12) of the printed circuit board.

Abstract: A substrate manufacturing plant comprising a plurality of minimum footprint skinned lines and methods relating to same. Specifically, a plant comprising a plurality of lines each line capable of accomplishing one step of a manufacturing process; the lines arranged in the order of their respective manufacturing steps so as to minimize the time necessary to process a work piece through all the lines; at least one line enclosed in its own environmental enclosure. By utilizing enclosures having the minimum size necessary to enclose and operate a single line or machine and arranging those enclosures in a linear fashion, parts progress linearly through the modules from start to finish without having to pass through a particular module more than once during processing. Because the size required to house a single machine is much smaller than a room designed to house multiple machines and people, control of the environment within the modules is relatively easy and cheap to accomplish.

Abstract: Forged connecting rod, in particular of an internal combustion engine, including a body (1), a connecting rod small end (2) and a connecting rod big end (3), forming two connecting rod small end and connecting rod big end bearings for receiving respectively a piston pin and a crankpin. The connecting rod is constituted by two half connecting rods (5) which are substantially symmetrical relative to a longitudinal median plane (6) of the connecting rod, which plane contains the longitudinal axis of the connecting rod, the joint surface (9) of the half connecting rods being essentially disposed in the median plane (6), the half connecting rods (5), each of which has a connecting rod half bearing (7) and a connecting rod big end half bearing (8).

Abstract: A method of machining a plurality of workpieces in an unmanned manner, including the steps of holding, with a jig, a first one of the workpieces, attaching the jig holding the first workpiece, to a workpiece holding device of at least one machining device, so that the first workpiece is machined by the machining device, detaching, after the machining of the first workpiece, the jig holding the first workpiece, from the workpiece holding device, removing the first workpiece from the jig, and holding, with the jig, a second one of the workpieces, and repeating the attaching step, the detaching step, and removing step.

Abstract: An automatic hard diskdrive read/write arm fabrication system, which includes a plurality of rotary tables arranged in a line, conveyer means arranged at one side of the rotary tables for carrying shaped material blocks to the rotary tables for processing into finished hard diskdrive read/write arm, a set of processing implement respectively disposed adjacent to the rotary tables and controlled to process shaped material blocks into finished hard diskdrive read/write arm, and a plurality of transferring tool means, for example, mechanical arms controlled to transfer shaped material blocks from the conveyer means to the rotary tables for processing by the processing implement respectively, and to transfer processed shaped material blocks from the rotary tables to the conveyer means.

Abstract: The invention relates to a method for the manufacture of a prefabricated motor vehicle door module and is directed to improving the manufacturing efficiency of complex technical systems with extensive cabling. The method for manufacturing the prefabricated motor vehicle door module with an electronics unit and several electrical components, such as a window regulator motor, central locking, mirror adjustment and heating, switches, lights, speakers, and a side bag, comprises fitting out of a support plate with the electrical components provided for a specific vehicle door and the cabling of the door by means of electrical leads; wherein the fitting out step is carried out in a main assembly line; wherein at least a part of the electrical leads is prefabricated as individual lead connections in a secondary cable production line in accurate sequence for the door module production in a production device and are mounted independently of each other directly on the door module in a main assembly line.

Abstract: The present invention relates to an apparatus for machining workpieces (W1 to W4) by stock removal, in particular the main (a1 to a5) and/or connecting rod bearing journals (b1 to b4) of crankshafts. For this purpose the apparatus is equipped with at least two guideways (7, 8) which are distanced from one another and are arranged parallel with respect to one another and on which at least one workpiece fixture (9, 10) holding a workpiece (W1to W4) each can be moved from a transfer position (P1, P2) to a working position (A1 to A6), and with two discoid cutters (17, 18, 21) of which each can be moved on a cutter guideway (13, 14, 19), which is arranged between the guideways (7, 8), from a first working position (A1, A2, A5) in which it works on the workpiece (W1, W3) held by the first workpiece fixture (9) to a second working position (A3, A4) in which it works on the workpiece (W2, W4) held by the second workpiece fixture (10).

Abstract: A high speed machining machine-tool including a mechanical module having a machining station and a driving station and an equipment module with “n” number different parts located up line. The module bases are connected to a common supporting frame, with the mechanical module being fixedly connected thereto. The equipment module is connected to the machine so as to slide on its longitudinal axis. The different mobile parts of the machine-tool adopt two positions: a first, so-called “folded” position, in which the equipment module and all its parts engage each other and the mechanical module; a second, so-called “extended” position, in which the whole equipment module or a subset of its component parts have slid on the supporting frame towards the rear so as to form a transversal handling passage running through and through the machine. The invention is useful for high speed machining.

Abstract: A system having improved cycle time for removing PC boards from a connected panel. In accordance with the present invention, a pair of walking clamps are used to receive a panel from a subsequent processing system, and a movable receiving nest is used to provide the PC boards to a subsequent processing station. The processes of receiving a panel, depaneling the PC board, and delivering the PC boards do not use common components and are able to operate independently and concurrently to reduce idle time in the system and improve the cycle time. The present invention also provides a secondary vacuums which removes debris from the PC boards as the PC boards are being transporting to a subsequent processing system to improve the removal of debris.

Abstract: A rotary transfer machine or rotary index table having an outer carriage ring subject to rotation about a central support frame. The rotary transfer machine includes a plurality of machining stations spaced at radial intervals about the carriage ring. The machining stations can provide outside machining stations on the outside of the carriage ring and inside machining stations mounted to the support frame inside of the carriage ring. The rotary transfer machine includes a plurality of pallets mounted around the carriage ring. Each pallet includes a clamp for holding workpieces to be machined therebetween. Each pallet includes a clearance opening which allows for cutting tools to extend through the pallets to machine the back side of the work piece and to allow for machining the work piece from all six sides.

Abstract: A circulating type milling apparatus for milling a lock core keyway includes a frame with a rotating disc that is intermittently rotated through a pre-determined angle. Lock core seats are equidistantly provided on the rotating disc. A milling disc is mounted to a top plate of the frame and includes cutters, ejecting plate, and detectors mounted thereon. The cutters are lowered to mill a keyway in each lock core. When the cutters are further moved downward and thus disengaged from the lock cores, the rotating disc is rotated by a distance that is equal to a half distance between two adjacent lock core seats such that each lock core seat is in a positioning in alignment with an associated detector yet not in alignment with an associated cutter. When the milling disc is moved upward, the detector checks whether the milled keyway of the lock core meets the required standard. The ejecting plate ejects the finished milled lock core, and a new lock core is fed by a lock core supplying device.

Abstract: An assembly for processing a flexible tape comprises a carrier frame having a slot and a cut-out region contiguous with one end of the slot for selectively transferring the flexible tape from the top surface of the carrier frame to the bottom surface of the carrier frame. An apparatus for processing the flexible tape is also disclosed and includes the carrier frame, a base having an aperture and a platform sized to fit within the aperture of the base. The base is pivotable around one end of the platform.

Abstract: A static ventilator provided with a deformable corrugated portion is described herein. The static ventilator is provided with a tubular base to be installed to the roof, a sleeve to be connected to the tubular base and a cover to be installed to the free end of the sleeve. The tubular base is provided with a deformable corrugated portion enabling the tubular base to be installed to a sloping roof while allowing the sleeve to be positioned and maintained in a generally vertical orientation. The present invention is also concerned with a method for forming a tubular base for static ventilator provided with a corrugated portion.

Abstract: Core-type structures are formed in a continuous process by assembling cut tubes or sheets of a thermoplastic material that are aligned, cut into separate continuous structures which are then subsequently cut into separate structures suitable for use as a core member.

Abstract: Core-type structures are formed in a continuous process by assembling cut tubes or sheets of a thermoplastic material that are aligned, cut into separate continuous structures which are then subsequently cut into separate structures suitable for use as a core member.

Abstract: A fully automatic cutting metal-working machine, which includes a material feed unit, a cutting metal-working main unit controlled to process metal rod material delivered from the material feed unit into finished products, and a waste material conveyer controlled to collect and carry waste material out of the cutting metal-working main unit, wherein the cutting metal-working main unit includes a machine base, a casing mounted on the machine base, a material cut-off shaft assembly controlled to cut metal rod material from the material feed unit into individual workpieces, a plurality of processing shaft assemblies mounted around the casing, a rotary center fixture holder mounted within the casing at the center and controlled to carry workpiece to each of the processing shaft assemblies in proper order to receive a respective processing procedure, and a steering shaft assembly controlled to reverse the position of workpiece at each fixture.

Abstract: A transfer line with devices for conveying work pieces along the central bases, lateral bases set up along the sides of the central bases on which the processing units are mounted so as to be capable of displacement, and supply devices for the processing stations. In order to improve access to the transfer line and simplify component units, the following features are proposed: a) the supply devices along the direction of travel of the work pieces are arranged exclusively within or in the region of and/or above the central bases; b) the supply devices are connected to each processing station via short detachable connecting pieces; c) shut-off devices are provided at least in the main lines for hydraulics, lubrication, pneumatics etc.; and d) at least one control block with valves is provided between the shut-off devices and the processing station.

Abstract: An automated machine tool is provided and includes a frame having a first workpiece transfer station at a first location on the frame; at least two self-contained processing units, each of the units including structure for holding the workpiece for processing and structure for performing a process on the workpiece; and structure for sequentially indexing the processing units to the first workpiece transfer station for transferring workpieces to and from each of the processing units.

Abstract: An automated assembly line is controlled by a computer system. The assembly line is comprised of a plurality of machines which are each segmented into its basic unit operations providing work stations. The work stations are then controlled by the computer system and operated asynchronously with respect to the other work stations of the assembly line.

Abstract: Each of plural workpiece transfer units 10 input from on end of a machining line 100 in turn is fed toward the other end thereof in a first horizontal direction by a linear motor. In this transfer process, the workpiece transfer unit 100 is indexed to the front of predetermined some of plural spindle heads 60 arranged along the machining line 100, in turn. At an indexed position of the workpiece transfer unit 10, a workpiece supporting device movably mounted on the workpiece transfer unit 10 in two direction mutually perpendicular to the first horizontal direction, performs the machining operation on a workpiece in accordance with an NC program with respect to a tool T attached to a tool spindle 66 of the spindle head 60. At generally the same time when the workpiece transfer unit 10 starts a transfer feed toward the next spindle head 60 after finishing the machining operation by one of the spindle heads 60, the tool spindle 66 of the next spindle head 60 is started to rotate.