Abstract: A chatter vibration detection method includes acquiring vibration data of a tool (4) at a time of machining a workpiece at a predetermined sampling period (?t), calculating an autocorrelation coefficient (Rxx?) corresponding to a time required for a cutting edge (4a, 4b) to contact the workpiece (W) several times based on acquired time series vibration data and calculating a period (Tx) of characteristics of the calculated autocorrelation coefficient (Rxx?), and deciding that chatter vibration occurs when a contact period (T1) at which the cutting edge (4a, 4b) contacts the workpiece (W) is not an integral multiple of the calculated period (Tx).
Abstract: A method for setting a working origin for a rotary tool in contact with a work piece to be machined, having: applying to a main spindle which holds the rotary tool, with a tip of a cutting edge of the rotary tool in contact with an outer surface of the work piece fixed to a work table, a load torque to such an extent that the rotary tool is not caused to be rotated; applying the load torque to the main spindle, and moving either the work table or the main spindle in a jog feed in a direction of any one of feed shafts such that the tip of the cutting edge is moved away from the outer surface along an axial direction of the rotary tool or in the direction orthogonal to the axial direction; and setting a coordinate at the moment when the main spindle starts rotation as a working origin of the jog feed in the direction of the any one of the feed shafts.
September 7, 2007
Date of Patent:
December 14, 2010
Tomohiko Kawai, Kenzo Ebihara, Yonpyo Hon
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: A system and method for monitoring the operating condition of an electrode dresser for an automated spot welder includes a sensor for sensing an operating characteristic of the dresser. The output produced by the sensor is analyzed by a data acquisition system to determine the operating condition of the dresser. Various types of sensors may be employed including a current sensor which senses current flowing through the dresser motor, a flux sensor which senses leakage flux produced by the dresser motor, and a vibration sensor which senses vibration produced during operation of the dresser. Operating characteristics determined by the data acquisition system include whether the electrode dresser is operational, whether the dresser has been engaged by the electrodes of the welder, the amount of time that the welder electrodes were in dress, and the quality of the dress.
Abstract: A machine tool comprises a spindle unit for raising a spindle on which a cutting tool is mounted by a magnetic force and supporting the spindle. The spindle unit carries out feedback control so as to maintain the spindle in its target position in the radial direction. A feeder for feeding the cutting tool to a work comprises a servo motor for moving the spindle unit relatively to the work. A feeding controller for controlling a feeding operation of the feeder controls the speed of rotation of the servo motor on the basis of feed speed data stored in a memory. The feed speed data comprises a first feed speed corresponding to the time when the cutting tool cuts through an end surface of the work crossing the direction of feeding and a second feed speed corresponding to the time of normal working and higher than the first feed speed.
Abstract: A tool abnormality detector for use with a machine tool for detecting any abnormality of a tool mounted on the tool mounting shaft. When the tool mounting shaft is in a correct position with respect to the tubular body secured to the spindle, the air pressure is kept constant. When an abnormal resistance is applied to the tool mounting shaft, the latter will lag in rotation with respect to the tubular body, so that the exhaust air passage will be blocked. A pressure sensor detects an abnormal increase in the air supply line, giving a signal for stopping the spindle of the machine tool. This prevents the tool from damage.
Abstract: An edge grinder includes a shaft for supporting a glass sheet template in spaced relationship to one another. The template and glass sheet are rotated about a sheet axis of rotation and a grinding wheel is rotated about a wheel axis of rotation. The grinding wheel and a template follower spaced from the grinding wheel are biased against the glass sheet and template respectively, to shape the glass sheet to a desired contour as defined by the template. As the grinding wheel engages varying edge damage and/or increased peripheral rotational speed of the sheet, the load on the motor powering the grinding wheel varies as indicated by current input to the grinding wheel motor. Variations in the current input are responded to by selectively varying the rotational speed of the sheet. In this manner, a uniform rate of material removal is maintained to eliminate overheating of the glass edge and grinding wheel during shaping of the glass sheet.
Abstract: A material forming machine comprising a forming tool driven by a forming tool motor, a workpiece, a feed drive motor, a sensor, and a reference signal, wherein said sensor varies the speed of the feed drive motor by responding to variations of the speed of the forming tool's motion, and wherein the reference signal remains constant. Said machine performs sawing, shaping, milling, drilling, hammering, shearing, chiseling, and cutting on irregularly shaped workpieces, having variations in density.
Abstract: Corrugated tubing is advanced along its axial path by rotatably driven lead screw members the screw threading of which is in meshing engagement with the corrugations of the tubing, the lead screw members being in pairs with the screw threading of the members of each pair being of opposite hand and the lead screw members of each pair being rotated in opposite directions. The lead screw members of each pair present outwardly directed cutters which are synchronized substantially simultaneously to intersect the tubing thereby, in perforating the tubing, to restrain the tubing against rotation thereof about the axial path. There is also disclosed a method of producing the lead screw members with the outwardly projecting cutters mounted thereon.