Row tool balance and bow correction apparatus

Claim 1

In an automated system for lapping thin film magnetic heads disposed in row on a bar, the improvement which comprises: a stationary fixture; a movable fixture carried on said stationary fixture; a lapping assembly including a rotary lapping plate; means for securing said bar in opposition to said lapping plate and comprising a plurality of struts and rods; means carried on said bar for generating data signals representing throat height during the lapping process; a data processor coupled to said signal generating means for producing command signals in response to said data signals; electromagnetic actuator means coupled to said data processor for automatically correcting the balance and bow of said bar relative to said lapping plate via said struts and rods in response to said command signals from said processor; a first set of said electromagnetic actuators is coupled to said bar via said rods for the correction of balance and a second set of electromagnetic actuators is coupled to said bar via said struts to correct for bow of said bar; said data processor, said data generating means, said signal generating means and said electromagnetic actuators define a closed loop lapping control system for correction of balance and bow of said bar; and said second set of electromagnetic actuators is carried on an equal numbered set of pivot pins and said struts carried on said set of pivot pins whereby pivotal movement thereof is in response to said data signals applied to said second set of electromagnetic actuators for correction of the bow of said bar.