A bearing apparatus includes a bearing that rotatably supports a main spindle around a rotation axis, a spacer including an inner-ring spacer adjacent to an inner ring of the bearing and an outer-ring spacer adjacent to an outer ring, and a heat flux sensor provided in an inside surface of the outer-ring spacer. A distance in a direction along the rotation axis from a center of the bearing to a center of the heat flux sensor is longer than 0.5 time and shorter than one time of a dimension of the bearing in the direction along the rotation axis.

A rotary shaft locking device includes a rotary shaft, a first angular contact ball bearing, a support, and an actuator. The rotary shaft is rotatable about a first axis and has a first contact surface. The first angular contact ball bearing includes an inner ring connected to the rotary shaft, an outer ring, and a plurality of balls disposed between the inner ring and the outer ring. The support has a second contact surface and rotatably supports the rotary shaft via the first angular contact ball bearing. The actuator is configured to move the rotary shaft and the inner ring with respect to the support and the outer ring in a first direction parallel to the first axis so that the first contact surface contacts the second contact surface to prohibit the rotary shaft from rotating and so that precompression that acts on the plurality of balls is reduced.

A rotary shaft locking device includes a rotary shaft, a first angular contact ball bearing, a support, and an actuator. The rotary shaft is rotatable about a first axis and has a first contact surface. The first angular contact ball bearing includes an inner ring connected to the rotary shaft, an outer ring, and a plurality of balls disposed between the inner ring and the outer ring. The support has a second contact surface and rotatably supports the rotary shaft via the first angular contact ball bearing. The actuator is configured to move the rotary shaft and the inner ring with respect to the support and the outer ring in a first direction parallel to the first axis so that the first contact surface contacts the second contact surface to prohibit the rotary shaft from rotating and so that precompression that acts on the plurality of balls is reduced.

A spindle arrangement for a machine tool comprising a spindle housing, which can be inserted and fixed in the machine tool, a spindle shaft being accommodated in the spindle housing, and a spindle head projecting from the spindle housing. At least one optical element is located on or near the spindle head, the optical element emits light in the region of the spindle head and/or to optically capture the region near the spindle head. At least one recess is provided on or near the spindle head, the optical element being insertable into the recess. The optical element is provided with at least two contacts arranged on the front face on different radial levels or in different axial regions relative to the screw axis on the end of the optical element which is screwed into the recess.

The present disclosure provides a conveniently operated electronic lathe, belonging to the technical field of electronic lathes. The conveniently operated electronic lathe includes a sliding plate box, a longitudinal and transverse reversing detection switch, a longitudinal and transverse operation handle, a rack, a longitudinal and transverse sliding plate, a numerical control system, an electric cabinet, a spindle box, a spindle gear shifting handle. A shaft I, a shaft II, a shaft III, a shaft IV and a shaft V are all rotatably arranged on the sliding plate box. A gear of the shaft III is fixed to the shaft III. A first gear of the shaft II is engaged with the gear of the shaft III. A second gear of the shaft IV is engaged with the first gear of the shaft V.

The present disclosure provides a conveniently operated electronic lathe, belonging to the technical field of electronic lathes. The conveniently operated electronic lathe includes a sliding plate box, a longitudinal and transverse reversing detection switch, a longitudinal and transverse operation handle, a rack, a longitudinal and transverse sliding plate, a numerical control system, an electric cabinet, a spindle box, a spindle gear shifting handle. A shaft I, a shaft II, a shaft III, a shaft IV and a shaft V are all rotatably arranged on the sliding plate box. A gear of the shaft III is fixed to the shaft III. A first gear of the shaft II is engaged with the gear of the shaft III. A second gear of the shaft IV is engaged with the first gear of the shaft V.

A milling machine includes a spindle which is arranged to receive a tool holder and in use to cause rotation of the tool holder within the spindle. A portion of the spindle housing surrounding the tool holder is provided with at least one pair of opposing damping units.

A milling machine includes a spindle which is arranged to receive a tool holder and in use to cause rotation of the tool holder within the spindle. A portion of the spindle housing surrounding the tool holder is provided with at least one pair of opposing damping units.

A measuring device for a spindle or for a rotary table includes at least two first and second position sensing elements and a scale element, having a first and second graduations and being rotatable about an axis of rotation relative to the position sensing elements. The first graduation includes regular structures arranged in parallel next to one another along a first direction, having a directional component in the circumferential direction. The second graduation includes regular structures arranged in parallel next to one another along a second direction, having a directional component in the axial direction. The first position sensing elements are offset from one another in the circumferential direction, and are able to scan the first graduation so that the position of the scale element in a plane having an orthogonal orientation to the axis of rotation is determinable. In addition, at least one of the first position sensing elements is able to determine an angular position of the scale element in relation to the first position sensing elements in absolute terms within and across a rotation. The second position sensing elements are offset from one another in the circumferential direction, and are able to scan the second graduation, and the axial position of the scale element is able to be determined.

A measuring device for a spindle or for a rotary table includes at least two first and second position sensing elements and a scale element, having a first and second graduations and being rotatable about an axis of rotation relative to the position sensing elements. The first graduation includes regular structures arranged in parallel next to one another along a first direction, having a directional component in the circumferential direction. The second graduation includes regular structures arranged in parallel next to one another along a second direction, having a directional component in the axial direction. The first position sensing elements are offset from one another in the circumferential direction, and are able to scan the first graduation so that the position of the scale element in a plane having an orthogonal orientation to the axis of rotation is determinable. In addition, at least one of the first position sensing elements is able to determine an angular position of the scale element in relation to the first position sensing elements in absolute terms within and across a rotation. The second position sensing elements are offset from one another in the circumferential direction, and are able to scan the second graduation, and the axial position of the scale element is able to be determined.