A machine tool and a control method for the machine tool, which determine the degree of misalignment during friction joint, are provided. The machine tool (an automatic lathe 1) includes: a first spindle 10 rotatably holding a first workpiece (a workpiece W1); a second spindle 20 arranged to face the first spindle and rotatably holding a second workpiece (a remaining workpiece W2); and a controller 40a, while rotating at least one of the first workpiece or the second workpiece, relatively moving the first spindle and the second spindle so as to get closer to each other and pushing a rear end portion of the second workpiece against a front end portion of the first workpiece to frictionally join the first and second workpieces. The controller has a misalignment amount detector detecting a misalignment amount s of the second workpiece with respect to the first workpiece during the friction joint.

Provided are a friction stir welding (FSW) device, FSW system, and FSW method with which it is possible to expand the applications of FSW while increasing processing accuracy. In a FSW device, when a first member to be welded and a second member to be welded are continuously welded by moving a processing tool in a linear or curved manner with the processing tool, while rotating, being pressed in the axial direction against the first member to be welded and the second member to be welded, a control device executes a reaction force correction control that controls the output of support member actuators so as to cancel the reaction force acting upon the processing tool as a result of the rotation of the processing tool.

The present disclosure provides a system and method for measuring energy conversion efficiency of an inertia friction welding (IFW) process in a non-contact manner. The system includes an IFW machine, a Hall sensor, a data acquisition module, a processing module and a stabilized direct current (DC) power supply. The stabilized DC power supply provides electrical energy for the Hall sensor. The Hall sensor is provided beside a flywheel of the IFW machine, so that the flywheel is within a detection range of the Hall sensor. A magnet is provided on the flywheel. The data acquisition module acquires a Hall electric potential change caused by a relative movement between the magnet and the Hall sensor during the IFW process, and transmits the Hall electric potential change to the processing module to calculate the energy conversion efficiency of the IFW machine.

The present invention concerns a method of detecting the making or breaking of contact of a sonotrode (4) which is caused to vibrate with a frequency f and a vibration amplitude A.sub.0 with a counterpart element (5). To provide a method with which contact-making or breaking of a sonotrode with a counterpart element can be particularly quickly and inexpensively detected it is proposed according to the invention that the method has the following steps: a) recording a time configuration of the vibration amplitude A.sub.0 (1) during a first measurement time interval ΔT, and b) determining from the time configuration of the vibration amplitude A.sub.0 (1) whether making or breaking of contact occurred within the measurement time interval ΔT.

The present disclosure provides a system and method for measuring energy conversion efficiency of an inertia friction welding (IFW) process in a non-contact manner. The system includes an IFW machine, a Hall sensor, a data acquisition module, a processing module and a stabilized direct current (DC) power supply. The stabilized DC power supply provides electrical energy for the Hall sensor. The Hall sensor is provided beside a flywheel of the IFW machine, so that the flywheel is within a detection range of the Hall sensor. A magnet is provided on the flywheel. The data acquisition module acquires a Hall electric potential change caused by a relative movement between the magnet and the Hall sensor during the IFW process, and transmits the Hall electric potential change to the processing module to calculate the energy conversion efficiency of the IFW machine.

A vibration welding system includes vibration welding equipment having a welding horn and anvil, a host machine, a check station, and a welding robot. At least one displacement sensor is positioned with respect to one of the welding equipment and the check station. The robot moves the horn and anvil via an arm to the check station, when a threshold condition is met, i.e., a predetermined amount of time has elapsed or a predetermined number of welds have been completed. The robot moves the horn and anvil to the check station, activates the at least one displacement sensor, at the check station, and determines a status condition of the welding equipment by processing the received signals. The status condition may be one of the alignment of the vibration welding equipment and the wear or degradation of the vibration welding equipment.

A robot control device includes a correction amount calculation unit that calculates a correction amount for collecting a deviation of a tip position of a tool attached to a tip of a robot due to an external force applied to the tool and a correction profile generation unit that generates a correction profile indicating a relationship between the correction amount calculated by the correction amount calculation unit and time.

A vibration welding system includes vibration welding equipment having a welding horn and anvil, a host machine, a check station, and a welding robot. At least one displacement sensor is positioned with respect to one of the welding equipment and the check station. The robot moves the horn and anvil via an arm to the check station, when a threshold condition is met, i.e., a predetermined amount of time has elapsed or a predetermined number of welds have been completed. The robot moves the horn and anvil to the check station, activates the at least one displacement sensor, at the check station, and determines a status condition of the welding equipment by processing the received signals. The status condition may be one of the alignment of the vibration welding equipment and the wear or degradation of the vibration welding equipment.

The present invention concerns a method of detecting the making or breaking of contact of a sonotrode (4) which is caused to vibrate with a frequency f and a vibration amplitude A.sub.0 with a counterpart element (5). To provide a method with which contact-making or breaking of a sonotrode with a counterpart element can be particularly quickly and inexpensively detected it is proposed according to the invention that the method has the following steps: a) recording a time configuration of the vibration amplitude A.sub.0 (1) during a first measurement time interval T, and b) determining from the time configuration of the vibration amplitude A.sub.0 (1) whether making or breaking of contact occurred within the measurement time interval T.

A vibration welding system includes vibration welding equipment having a welding horn and anvil, a host machine, a check station, and a welding robot. At least one displacement sensor is positioned with respect to one of the welding equipment and the check station. The robot moves the horn and anvil via an arm to the check station, when a threshold condition is met, i.e., a predetermined amount of time has elapsed or a predetermined number of welds have been completed. The robot moves the horn and anvil to the check station, activates the at least one displacement sensor, at the check station, and determines a status condition of the welding equipment by processing the received signals. The status condition may be one of the alignment of the vibration welding equipment and the wear or degradation of the vibration welding equipment.