Method for lapping and a lapping apparatus
AssigneeMurata Manufacturing Co., Ltd.
InventorNobuyuki Hori
Life of this patent
Estimating the term…
Abstract
A method for lapping which eliminates lapping damage includes a high-speed lapping operation at a high torque which is continuously performed after performing intermittently a low-speed lapping operation under low torque on a workpiece. Therefore, the excessive load during a first lapping stage due to the projection on the surface of the workpiece is greatly decreased. A continuous lapping is performed after the projection becomes smooth to some extent, and thus the lapping damage is prevented.
Claims19
A method for lapping a workpiece comprising the steps of:
- a first step of intermittently lapping the workpiece;
- and
- a second step of continuously lapping the workpiece.
A lapping apparatus for lapping a workpiece, the apparatus comprising:
- an epicyclic-gear-shaped carrier capable of holding several workpieces;
- a sun gear arranged to mesh with the carrier;
- a ring gear arranged to mesh with the carrier;
- lap surface plates arranged at the upper portion and the lower portion of the carrier, respectively;
- an electric motor for driving the carrier and which rotates at least one of the sun gear and the ring gear;
- a first controller arranged to control the electric motor to perform a first-stage driving in which the electric motor is intermittently driven at a relatively low torque;
- a second controller arranged to perform a second-stage driving in which the electric motor is continuously driven at a relatively high torque after finishing the intermittent driving with a low torque;
- and
- a switch arranged to switch between the first controller to perform the first-stage driving and the second controller to perform the second stage driving.
A lapping apparatus for lapping a workpiece, the apparatus comprising:
- a epicyclic-gear-shaped carrier capable of holding several workpieces;
- a sun gear arranged to mesh with the carrier;
- a ring gear arranged to mesh with the carrier;
- lap surface plates arranged at the upper portion and the lower portion of the carrier, respectively;
- an electric motor for driving the carrier and which rotates at least one of the sun gear and the ring gear;
- a low torque motor;
- a high torque motor;
- a low torque drive circuit arranged to perform an intermittent driving of at least one of the sun gear and the ring gear via the low torque motor;
- a high torque drive circuit arranged to perform a continuous driving of at least one of the sun gear and the ring gear via the high torque motor after the intermittent driving is finished;
- and
- a switch arranged to switch operation between the low torque drive circuit and the high torque drive circuit.
Dependencies are inferred from the claim text.