| 摘要 |
A cylindrical grinding apparatus of the present invention includes a wheel mounted at a front end of a spindle to grind a workpiece, and a headstock to support a rotation of the spindle, which is inserted into a shaft insert hole through first and second bearings separately coupled at an inner part of the shaft insert hole through which the spindle is inserted. The cylindrical grinding apparatus includes: an oil tank provided at a lower part of an inner part of the headstock to store an oil supplied to the first and second bearings; a motor housing having a front end mounted to the headstock from an opposite side of the wheel; a drive motor installed inside the motor housing such that a front end of the rotating shaft of the drive motor matches with the other end of the spindle in the axial direction to transfer rotational force to the spindle; a sealing unit installed at the other end of the spindle between the headstock and the motor housing to prevent oil, which flows in between the first and second bearings and the shaft insert hole, from flowing into an inside of the drive motor by allowing an exterior air to flow in; a third bearing installed on the other end of the rotating shaft of the drive motor; and a housing cover installed on the other end of the motor housing. According to the present invention, by applying a direct motor connecting scheme, which directly transfers a driving force of the motor to the spindle, instead of a drive force transfer scheme through a belt, the rotation of the spindle is stably supported while improving a rotation accuracy, and an oil is smoothly supplied to the spindle to minimize a thermal expansion transformation, thus improving the machining accuracy. |
