Bar feeder (1) comprising a guide channel (10) centred on an invariable guide axis (A-A), characterised in that the guide channel (10) is adjustable and is formed by an adjustable guide element which can define a guide channel with a constant centre (C) corresponding to a bar diameter comprised between a maximum bar diameter (DMax) in a first position (P1) and a minimum bar diameter (DMin) in a second position (P2) under the action of a device for adjusting the diameter of the guide channel (2).

Bar feeder (1) comprising a guide channel (10) centred on an invariable guide axis (A-A), characterised in that the guide channel (10) is adjustable and is formed by an adjustable guide element which can define a guide channel with a constant centre (C) corresponding to a bar diameter comprised between a maximum bar diameter (DMax) in a first position (P1) and a minimum bar diameter (DMin) in a second position (P2) under the action of a device for adjusting the diameter of the guide channel (2).

A material bar magazine for guiding material bars on an automatic lathe and a system having such a magazine and automatic lathe having at least one headstock that is displaceable along a longitudinal axis of the material bar magazine, where the material bar magazine includes a material bar-guiding channel system having a channel opening system. Further, the channel system of the material bar magazine has a first, outer guide channel and a second, inner guide channel mounted inside the first guide channel such that it can move relative thereto along the longitudinal direction, the second, inner guide channel couplable or coupled to the headstock of the automatic lathe for moving the second, inner guide channel as a result of a change in position of the headstock along a longitudinal axis of the material bar magazine in overrun condition synchronously therewith along the longitudinal axis and relative to the first guide channel.

A cutting apparatus includes a cutting tool having a cutting edge, an excitation part structured to apply excitation to the cutting tool, and a drive part structured to apply a voltage to the excitation part to reciprocate the cutting edge of the cutting tool. The excitation part suppresses residual oscillations by applying excitation that contains an excitation force of components of frequencies higher than a resonance frequency and has an excitation force of the resonance frequency suppressed. The excitation part applies a first excitation, and applies a second excitation after an elapse of a time 0.5 times as long as a resonance period from timing at which the first excitation is applied to suppress residual resonance oscillations.

An apparatus includes a self-centring device for centring and guiding a bar, tube or the like to be advanced to a spindle of a machine tool, includes a hollow containing body with through opening having a longitudinal axis, for receiving a bar to be fed along an advancement direction to the spindle; in the body an inner sliding surface is defined that is tilted with respect to the longitudinal axis; centring and guiding elements are provided housed in the hollow body and shaped for coming into contact with the bar and exert thereupon a distributed centring and guiding action; the centring and guiding elements that are slidable along the inner surface for the distance thereof from the longitudinal axis to adapt to different bar diameters; in the body an elastic member is housed to urge the centring and guiding elements to the position of minimal reciprocal distance so as to induce and maintain, during operation, the centring and guiding elements in contact with the surface of the bar. An advancement device is further disclosed for the bar, having a supporting and guiding member configured for restingly receiving, from a first side, a bar and configured for guiding said bar along an advancement direction, a movable grasping member mobile from a disengaged position, further from the member to be separated from the bar, to a locking position, nearer said supporting member to press longitudinally the bar from a second opposite side against the supporting member; advancement motor device is configured for rotating the supporting and guiding member and/or the movable grasping member in the locking position to draggingly advance the bar along the advancement direction.

An apparatus includes a self-centring device for centring and guiding a bar, tube or the like to be advanced to a spindle of a machine tool, includes a hollow containing body with through opening having a longitudinal axis, for receiving a bar to be fed along an advancement direction to the spindle; in the body an inner sliding surface is defined that is tilted with respect to the longitudinal axis; centring and guiding elements are provided housed in the hollow body and shaped for coming into contact with the bar and exert thereupon a distributed centring and guiding action; the centring and guiding elements that are slidable along the inner surface for the distance thereof from the longitudinal axis to adapt to different bar diameters; in the body an elastic member is housed to urge the centring and guiding elements to the position of minimal reciprocal distance so as to induce and maintain, during operation, the centring and guiding elements in contact with the surface of the bar. An advancement device is further disclosed for the bar, having a supporting and guiding member configured for restingly receiving, from a first side, a bar and configured for guiding said bar along an advancement direction, a movable grasping member mobile from a disengaged position, further from the member to be separated from the bar, to a locking position, nearer said supporting member to press longitudinally the bar from a second opposite side against the supporting member; advancement motor device is configured for rotating the supporting and guiding member and/or the movable grasping member in the locking position to draggingly advance the bar along the advancement direction.

A control part of a control device includes a learning controller and a learning determination part. The learning controller performs learning control in which a correction amount of a resultant command is obtained, based on an oscillation phase obtained from an oscillation command and the resultant command, and the correction amount is added to the resultant command. The learning determination part determines whether or not the oscillation amplitude of the oscillation command is smaller than a predetermined threshold, and when the oscillation amplitude is smaller than the predetermined threshold value, the learning determination part both sets the oscillation command generated by an oscillation command generation part to zero and turns off the learning control or only turns off the learning control.

A control part of a control device includes a learning controller and a learning determination part. The learning controller performs learning control in which a correction amount of a resultant command is obtained, based on an oscillation phase obtained from an oscillation command and the resultant command, and the correction amount is added to the resultant command. The learning determination part determines whether or not the oscillation amplitude of the oscillation command is smaller than a predetermined threshold, and when the oscillation amplitude is smaller than the predetermined threshold value, the learning determination part both sets the oscillation command generated by an oscillation command generation part to zero and turns off the learning control or only turns off the learning control.

A bar feeding device, for example for a lathe, and a process for using a bar feeding device This bar feeding device comprises: a base extending lengthwise, a channel cover extending lengthwise and rotatably connected to the base, a guiding member comprising a guiding channel extending lengthwise, a pusher flag, a mover, such as an endless chain, fastened to a first end of the pusher flag and able to move the pusher flag lengthwise, a push bar able to move within the guiding channel and fastened to a second end of the pusher flag. The channel cover comprises at least one displaceable member and an displacer for actively displacing the displaceable member relative to the channel cover.

A bar feeding device, for example for a lathe, and a process for using a bar feeding device This bar feeding device comprises: a base extending lengthwise, a channel cover extending lengthwise and rotatably connected to the base, a guiding member comprising a guiding channel extending lengthwise, a pusher flag, a mover, such as an endless chain, fastened to a first end of the pusher flag and able to move the pusher flag lengthwise, a push bar able to move within the guiding channel and fastened to a second end of the pusher flag. The channel cover comprises at least one displaceable member and an displacer for actively displacing the displaceable member relative to the channel cover.