Abstract: A working machines includes an identifying unit. A force sensor detachably supports a working head in the identifying unit. A controller circuit is designed to identify the working head based on the load detected at the force sensor. When the working head is replaced with another one, the load changes in the force sensor in the identifying unit. In general, the individual working head has the specific weight. The working heads can thus be differentiated from each other based on the weight. Accordingly, the controller circuit is allowed to reliably identify the working head after the replacement with a higher accuracy based on the detected load.

Abstract: A contact member is supported on the support shaft. A force sensor is coupled to the support shaft. A movable member is coupled to the force sensor. The pressure apparatus allows the movable member to cause the axial movement of the support shaft. A first guide serves to guide the axial movement of the support shaft. The first guide is supported on the support member. The support member stands still during the movement of the movable member. Accordingly, the movement of the movable member is restrained in the axial direction. The contact member is thus prevented from suffering from a swinging movement around the force sensor. Servo control of a higher frequency bandwidth can be applied to the movement of the contact member. The contact member moves at a higher velocity. Occurrence of resonance is still avoided in the contact member. The tact time can be shortened.

Abstract: A vibration extraction processing unit extracts a deflection component synchronous with a rotation from a clock signal of a non-contact sensor so as to correct a clock jitter. A clock generating unit generates a clock signal of any format frequency preliminarily set up according to the clock signal from the vibration extraction processing unit. A sector correction processing unit measures an error due to the frequency deflection so as to correct the writing start position for the format pattern signal of each sector containing a servo frame signal stored in a memory according to the measured error. Writing processing units read out the corrected format pattern signal from the memory according to a synchronous signal corresponding to a single turn of a disc and a format frequency clock signal and then writes into a disc medium face.