A method for improving service life of a magnetron, which belongs to the technical field of microwave applications, includes: taking anode working voltage range is taken as n voltage values U1 . . . Un constituting an arithmetic sequence; taking the voltage value as the anode voltage; in each voltage value, adjusting the magnet coil current between I min and Imax by the coil current control part , so that the output power P of the experimental magnetron is equal to the target power P0, and measuring the cathode filament temperature at this time by the temperature measuring part, which is denoted as Ti; measuring all the cathode filament temperatures Ti as the temperature data set corresponding to P0 by the temperature measuring part; taking out the minimum temperature value Tmin in the temperature data set, and using the anode voltage value and the magnet coil current value corresponding to Tmin as the working magnetron, wherein the output power is the anode voltage value and the magnet coil current value of P0. The present invention provides a method for improving the service life of a magnetron, which adjusts the electric field and the magnetic field, finds the synergy between the magnetic field and the electric field, and improves the service life of the magnetron.

The inventive concept relates to an apparatus for aging a field emission device configured to emitting electrons based on an electric field between a first electrode and a second electrode, and an aging method thereof. The apparatus according to an embodiment of an inventive concept includes a voltage generator and a current controller. The voltage generator increases the voltage applied to the first electrode to the target voltage level during the first time. The current controller increases the field emission current for the second time to the target current level and increases the pulse width of the field emission current for the third time to the target pulse width. According to the inventive concept, the performance of a large field emission device may be improved with high efficiency and low cost.

The inventive concept relates to an apparatus for aging a field emission device configured to emitting electrons based on an electric field between a first electrode and a second electrode, and an aging method thereof. The apparatus according to an embodiment of an inventive concept includes a voltage generator and a current controller. The voltage generator increases the voltage applied to the first electrode to the target voltage level during the first time. The current controller increases the field emission current for the second time to the target current level and increases the pulse width of the field emission current for the third time to the target pulse width. According to the inventive concept, the performance of a large field emission device may be improved with high efficiency and low cost.

An apparatus for manufacturing a spark plug by working of a workpiece with dies, wherein the workpiece has a metal shell part to be processed into a metal shell of the spark plug and a ground electrode part to be processed into a ground electrode of the spark plug. In the manufacturing apparatus, a position of the ground electrode part is measured in a non-contact manner by a position measurement unit in a state where the workpiece is held in position by a holding unit. The dies are controlled by a die control unit so as to adjust the working phase of the dies relative to the workpiece based on the measured position of the ground electrode part and then effect working of the workpiece with the dies.