Apparatus for automatic lapping control
Patent 4407094 Issued on October 4, 1983. Estimated Expiration Date: 
November 3, 2001. Estimated Expiration Date is calculated based on simple USPTO term provisions. It does not account for terminal disclaimers, term adjustments, failure to pay maintenance fees, or other factors which might affect the term of a patent.
November 3, 2001. Estimated Expiration Date is calculated based on simple USPTO term provisions. It does not account for terminal disclaimers, term adjustments, failure to pay maintenance fees, or other factors which might affect the term of a patent.Patent References 2499635 Apparatus for automatic lapping control Apparatus for automatic lapping control Patent #: 4199902 InventorsAssigneeApplicationNo. 06/317778 filed on 11/03/1981US Classes:451/1, PRECISION DEVICE OR PROCESS - OR WITH CONDITION RESPONSIVE CONTROL318/478, Electrical conditions in circuit other than controlled motor circuit451/269Rotary work holderExaminersPrimary: Whitehead, Harold D.Attorney, Agent or FirmInternational ClassesB24B 37/04 (20060101)B24B 49/00 (20060101) AbstractApparatus for automatic lapping control, based on imbedding an electrode in a lap plate of a lap machine and including at least one piezoelectric wafer in the lap load. Connected with the electrode is an automatic control circuit used for sensing the resonance frequency of the piezoelectric wafer and for terminating lapping when the resonance frequency reaches a presetable target frequency. Also connected with the electrode is an impedance comparator circuit used for sensing the presence and absence of a piezoelectric wafer at the electrode face and for activating the automatic control circuit in the presence of a wafer and deactivating the control circuit in the absence of a wafer. | |
