Main spindle unit and machine tool
AssigneeMitsubishi Heavy Industries Machine Tool Co., Ltd.
InventorKoichi Masuo
Life of this patent
Estimating the term…
Abstract
The main spindle unit has a main spindle, a front bearing, a rear bearing, a front case for covering the front bearing, and a rear case for covering the rear bearing. The front case has a front body part for holding the front bearing and a front flange part extending radially outward from the front body part. The rear case has a rear body part for holding the rear bearing and a rear flange part extending radially outward from the rear body part. A front mounted surface, which can be brought into contact with a first mounting surface of a unit support table, is formed on the front flange part so as to face the front side thereof. A rear mounted surface, which contacts a second mounting surface of the unit support table, is formed on the rear flange part so as to face the front side thereof.
Claims8
A main spindle unit which is attached to a unit support table which supports a first end of a tool such that the tool is able to rotate about an axis and holds a second end of the tool to rotate the tool about the axis, the unit comprising:
- a main spindle which extends in an axial direction, in which the axis extends, about the axis;
- a motor rotor which is fixed to an outer periphery of the main spindle;
- a motor stator which is disposed on an outer periphery of the motor rotor;
- a holder which is provided on a front side which is one end side of the main spindle in the axial direction and holds the tool;
- a front bearing which is disposed on the front side of the motor rotor and on a rear side of the holder, the rear side being a side opposite to the front side, and rotatably supports the main spindle;
- a rear bearing which is disposed on the rear side of the motor rotor and rotatably supports the main spindle;
- a motor case which has a tubular shape about the axis and in which the motor stator is fixed to an inner peripheral surface thereof;
- a front case which covers an outer periphery of the front bearing;
- and
- a rear case which covers an outer periphery of the rear bearing,
- wherein the front case has a front body portion which covers the outer periphery of the front bearing to hold the front bearing and a front flange portion which extends radially outward with respect to the axis from an outer periphery of the front body portion,
- wherein the rear case has a rear body portion which covers an outer periphery of the rear bearing to hold the rear bearing and a rear flange portion which extends radially outward from an outer periphery of the rear body portion,
- wherein an outer diameter of the front body portion is smaller than an inner diameter of the motor case,
- wherein in the front flange portion, a front mounted surface which is able to come into contact with a first mounting surface of the unit support table facing the rear side and a contact surface which is in contact with the motor case are formed so as to face the front side,
- wherein an outer diameter of the rear flange portion is larger than an outer diameter of the motor case, and
- wherein in the rear flange portion, a rear mounted surface which is in contact with a second mounting surface of the unit support table facing the rear side is formed so as to face the front side.
Dependencies are inferred from the claim text.