The present disclosure relates to an apparatus for cooling a ram spindle and compensating for a load and a machine tool including the same, in which a cooling unit cools a friction part between a ram spindle and a saddle when the ram spindle, which is transferred by means of the box guideway, is thermally deformed, and a hydraulic pressure closed circuit automatically compensates for a load applied to a plurality of gibs, which is provided inside the saddle and installed between the saddle and the ram spindle, except for a reference surface with which the ram spindle is in close contact, so as to correspond to the reference surface in a horizontal direction or a vertical direction in case that a load applied to the gib is changed by thermal deformation of the ram spindle even though the cooling unit is used, such that the surface pressure applied to the gib is automatically and constantly maintained, which makes it possible to improve machining precision of the machine tool, reduce machining costs by preventing a waste of resources, improve productivity by increasing a non-machining time, and improve stability and reliability of the machine tool.

A spindle includes a housing including a first opening, a bearing housed in the housing, a main shaft rotatably supported by the bearing, a collet chuck in a first through hole defined in the main shaft to grip a machining tool and being movable in an axial direction of the main shaft, a draw bar connected to the collet chuck, and a cover covering the first opening and including a second through hole through which the main shaft is disposed. The main shaft and the cover are disposed at a distance from each other.

A machine tool for cutting a workpiece with a cutting tool, includes a spindle motor that generates heat, a spindle head for supporting the spindle motor, and a heat insulating sheet disposed between the spindle motor and the spindle head. The area of a part of the heat insulating sheet that is in contact with a part of the spindle head having a high heat capacity is small so as to increase the amount of heat transferring from the spindle motor to the part of the spindle head having a high heat capacity, and thereby make the temperature distribution of the spindle head uniform.

A cutting fluid supplying device for a machine tool includes a machine tool having a structure body including a bed, a column disposed on the bed, and a spindle head disposed to the column and at least one of the ejection ports for ejecting a cutting fluid. The cutting fluid supplying device for a machine tool further includes a storage tank for storing the cutting fluid to be supplied to the machine tool, at least one of the cutting fluid flow passages for connecting the storage tank and the at least one of the ejection ports, and at least one of the pumps for applying pressure to the cutting fluid to supply the cutting fluid stored in the storage tank to the at least one of the cutting fluid flow passages. The at least one of the cutting fluid flow passages is disposed to penetrate through or disposed on an outer surface of the structure body so as to allow heat exchange between the cutting fluid and the structure body.

A power-tool cooling apparatus for a portable power tool comprises at least one cooling unit configured to generate a cooling fluid flow to cool a drive unit of the portable power tool, and at least one further cooling unit configured to generate a further cooling fluid flow. The at least one further cooling unit is designed to differ from the at least one cooling unit.

A motor, to which a rotary joint supporting structure for supporting a rotary joint is attached, turns a spindle. The motor includes a motor housing, a rotary shaft having a hollow shape and penetrating through the motor housing in the axial direction of the spindle, a flinger integrally attached to the rotary shaft outside the motor housing and disposed on the side to which the rotary joint supporting structure is attached, and a peripheral wall provided on the motor housing and projecting in the axial direction of the spindle so as to surround the periphery of the flinger. A plurality of cutouts are formed in the peripheral wall so as to establish communication between the interior and the exterior of the peripheral wall.

In a precision machine tool wherein a spindle head that is movable in the up and down direction is disposed on a column disposed on a bed and a water storage space for storing temperature-regulated cooling water is formed inside the column, the column has, in a lower part thereof, intake ports through which cooling water is led into the water storage space, the column has, in an upper part thereof, and an air vent hole through which air in the column is discharged is formed at a position higher than the drain opening.

A method for controlling a temperature adjustment system of a machine tool is provided. With the method, a temperature rise value T.sub.k of a main spindle device after stopping of rotation of a main spindle is obtained by using a reference temperature measured by a machine body temperature sensor mounted in a portion other than the main spindle device of a machine tool to calculate an estimated temperature y.sub.k. Therefore, as compared to a conventional method based only on a temperature of a cooling medium, supply of the cooling medium by a cooling device can be stopped or an operation of the cooling device can be switched from a first mode to a second mode without deteriorating machining accuracy in the main spindle device, thereby efficiently reducing power consumption.

A machine tool including a first cooling unit, such as a fan, that cools at least one of a drive part that drives a component of the machine tool and an amplifier of the drive part, a second cooling unit, such as a Peltier element, that cools the at least one of the drive part and the amplifier, and a cooling control unit that controls the first cooling unit and the second cooling unit, wherein vibration caused by the second cooling unit is less than vibration caused by the first cooling unit, and the cooling control unit switches cooling of the at least one of the drive part and the amplifier, from cooling by the first cooling unit to cooling by the second cooling unit.

A motor spindle is provided for a machine tool comprising a spindle housing for stationary mounting on the machine, a spindle assembly, removable from the spindle housing, with a rotor that is supported in an integrated bearing unit so as to be rotatable relative to the spindle housing, and a clamping mechanism for a tool, the clamping mechanism being actuatable via a clamping piston that is movable in an annular cylinder in the spindle housing, wherein the spindle assembly is designed with internal cooling that is suppliable with a cooling fluid via a coolant supply, wherein the coolant supply has a rotary feedthrough with an interface between a stationary component and a rotating component of the coolant supply, and wherein the bearing unit is also removable when the spindle assembly is removed from the spindle housing.