A method of manufacturing a transmission case housing is provided wherein a minimum quantity of lubrication as a compressed air/oil mist is supplied as the housing is rough bored and face milled. The transmission case defines a plurality of transmission fluid drainage holes for draining transmission fluid from the transmission when installed in a vehicle. The housing is positioned with the fluid drainage holes below a central axis of the housing and a plurality of internal bores and faces are bored and face milled on the housing. The compressed air/oil mist is sprayed from the cutting head to cool and lubricate the boring and face milling tools. Machining chips are blown off the rough bored housing through the fluid drainage holes.

A machine tool includes a base, a table, a main spindle, and a trunnion unit. The table is installed on the base. A tool is mounted to the main spindle. The main spindle is caused to approach a workpiece on the table along an up-down direction. The trunnion unit is configured to rotatably hold the table on which the workpiece is placed using a rotation axis along a front-rear direction as a center. The trunnion unit is disposed movable in a right-left direction.

Two cylinder heads are disposed side by side. Upper side intake valve holes of one of the cylinder heads and upper side exhaust valve holes of the other of the cylinder heads are simultaneously machined by a multi-spindle head integrally including intake side tools and exhaust side tools. After moving the one of the cylinder heads upward by a pitch of the intake valves and moving the other of the cylinder heads upward by a pitch of the exhaust valves, remaining intake valve holes of the one of the cylinder heads and remaining exhaust valve holes of the other of the cylinder heads are simultaneously machined.

A method of manufacturing a transmission case housing is provided wherein a minimum quantity of lubrication as a compressed air/oil mist is supplied as the housing is rough bored and face milled. The transmission case defines a plurality of transmission fluid drainage holes for draining transmission fluid from the transmission when installed in a vehicle. The housing is positioned with the fluid drainage holes below a central axis of the housing and a plurality of internal bores and faces are bored and face milled on the housing. The compressed air/oil mist is sprayed from the cutting head to cool and lubricate the boring and face milling tools. Machining chips are blown off the rough bored housing through the fluid drainage holes.

A machine tool includes a base, a table, a main spindle, and a trunnion unit. The table is installed on the base. A tool is mounted to the main spindle. The main spindle is caused to approach a workpiece on the table along an up-down direction. The trunnion unit is configured to rotatably hold the table on which the workpiece is placed using a rotation axis along a front-rear direction as a center. The trunnion unit is disposed movable in a right-left direction.

A workpiece clamping apparatus for a machine tool is proposed, including at least one receptacle for a workpiece, wherein the at least one receptacle includes a wall and an opening via which the workpiece is insertable into the receptacle in a linear direction and removable therefrom in a counter-direction, a clamping device for fixing the workpiece at the at least one receptacle, a first access area via which a first tool engages the workpiece for a first working operation, a counter-bearing for the first tool, and a second access area via which a second tool engages the workpiece for a second working operation, wherein the first working operation and the second working operation are performed at different locations on the workpiece using different tools and wherein the workpiece clamping apparatus is free of a counter-bearing for the second tool.