Abstract: The invention relates to a process for producing a dental restoration part using a machine tool (10), especially a dental processing machine intended for a dentist's office, wherein, in a first step, a rotating processing tool (16) rotationally mills or processes or grinds a workpiece (18) while, except from at least one entry and/or exit path, it is in continuous contact with the workpiece (18), i.e. with 0% air battle, by machining the outer profile (19) of the workpiece (18) substantially completely in helical-shape. The invention also relates to a dental processing machine.

Abstract: A dental milling machine is provided with a tool which is guided in a chuck. A workpiece arm is mounted opposite the tool to be able to be moved at least in the direction of the spindle axis. With a control device it can be moved in relation to the workpiece, especially by means of a drive motor of the workpiece arm. The workpiece arm has an abutment element, whereby the control device moves the tool and the abutment element towards each other until they abut each other. The control device can be used to detect abutment of the abutment element with respect to the tool, in particular with respect to its tip, in particular by decelerating the (relative) movement of the tool and the abutment element towards each another, upon contact of the tool and the abutment element. This position may be signaled as a reference position and, especially may be stored.

Abstract: The invention relates to a process for producing a dental restoration part using a machine tool (10), especially a dental processing machine intended for a dentist's office, wherein, in a first step, a rotating processing tool (16) rotationally mills or processes or grinds a workpiece (18) while, except from at least one entry and/or exit path, it is in continuous contact with the workpiece (18), i.e. with 0% air battle, by machining the outer profile (19) of the workpiece (18) substantially completely in helical-shape. The invention also relates to a dental processing machine.

Abstract: A dental milling machine is provided with a tool which is guided in a chuck. A workpiece arm is mounted opposite the tool to be able to be moved at least in the direction of the spindle axis. With a control device it can be moved in relation to the workpiece, especially by means of a drive motor at the workpiece arm. The workpiece arm has an abutment element, whereby the control device moves the tool and the abutment element towards each other until they abut each other. The control device can be used to detect abutment of the abutment element with respect to the tool, in particular with respect to its tip, in particular by decelerating the (relative) movement of the tool and the abutment element towards each another, upon contact of the tool and the abutment element. This position may be signaled as a reference position and, especially may be stored.

Abstract: The invention relates to a machine tool, hi particular a lathe grinding machine, comprising a tool spindle, a spindle motor and a tool clamped in a covet, with which tool a workpiece may be machined which may be moved in several axes relative to the tool, and comprising a control device for the tool spindle which controls the spindle motor. A spindle load detection device (24) which is connected with the control device (20) is provided and the control device (20) compares the output signal (26) of the spindle load detection device (24) with a predetermined threshold value (50), said threshold value (50) being below, in particular at least 20% below, the breaking load (54) of the tool (18). The control device (20) turns off the spindle motor (14) when the output signal (26) of the spindle load detection device (24) exceeds the threshold value (50).

Abstract: The invention relates to a machine tool, in particular a lathe grinding machine, comprising a tool spindle having a collet and a spindle motor, wherein the collet has at least two clamping jaws which are actuatable for receiving and releasing a tool, and comprising an air channel which runs radially on the outside of the collet, wherein the air channel is configured as a sealing air channel (42) and forms a positive pressure chamber (44) at least partially above the clamping jaws (26).

Abstract: A dental milling machine is provided with a tool which is guided in a chuck. A workpiece arm is mounted opposite the tool to be able to be moved at least in the direction of the spindle axis. With a control device it can be moved in relation to the workpiece, especially by means of a drive motor of the workpiece arm. The workpiece arm has an abutment element, whereby the control device moves the tool and the abutment element towards each other until they abut each other. The control device can be used to detect abutment of the abutment element with respect to the tool, in particular with respect to its tip, in particular by decelerating the (relative) movement of the tool and the abutment element towards each another, upon contact of the tool and the abutment element. This position may be signaled as a reference position and, especially may be stored.

Abstract: The invention relates to an arrangement of a machine tool (10) and a workpiece holder (111) connected to a workpiece (14), wherein the workpiece holder (111) comprises at least one surface (111a) pointing radially towards the outside, in particular a substantially planar surface, which is configured for contact with a clamping element (109) of a multi-axis workpiece arm (11) which clamping element (109) is disposed in the radial direction between the workpiece holder (111) and a chuck (120), wherein the clamping element (109) is displaceable relative to the chuck (120) for clamping and releasing the workpiece holder (111), wherein the clamping element (109) is configured to vary a clamping force (F) exerted on the workpiece holder (111) when it is displaced relative to the chuck (120).

Abstract: The invention relates to a machine tool (1), in particular a dental milling machine or mill-turning machine, comprising a spindle (10) for receiving a tool and a working arm (12) for receiving a workpiece and comprising at least one nozzle (14a) attached to the spindle (10), in particular with its outlet direction (R) substantially parallel to the axis of rotation (A) of the spindle (10), characterized in that a deflecting body (16) is attached to the spindle (10) or clamped therein, said deflecting body extending in particular at least partially in front of the nozzle (14a). Further, the invention relates to a method of operating the machine tool (1).

Abstract: A dental milling machine comprising a workpiece holder (2) and a changer arm (10) is characterized in that the changer arm (10) has a substantially U-shaped gripping attachment (12) and in that a tool (14) of the dental milling machine (1) has a tool fixation element (16). The tool fixation element has grooves (18) or holding projections at two mutually opposed positions which face away from each other, over which grooves or holding projections the U-shaped gripping attachment (12) of the changer arm (10) can engage, wherein parts of the U-shaped gripping attachment (12), more particularly the side flanks (12a, 12b) of the U-shaped gripping attachment (12), make contact with the grooves (18) or holding projections of the tool fixation element (16) under preload.

Abstract: The invention relates to a machining device for the machine-assisted production and machining of dental workpieces (16), particularly of artificial teeth and/or other dental replacement parts, the at least one workpiece (16) being clamped in at least one workpiece retainer (11) which can be raised, lowered and rotatably driven, is positioned on a rotational axis (9), and, for the purpose of machining, feeds said workpiece (16) to at least one tool spindle (4, 5, 6) that is rotationally driven and has a tool (7) secured thereto, an additional tool retainer (2, 2a, 2b) with a plurality of tools (7) arranged thereupon being associated with said workpiece retainer (11, 11a, 11b) and lying opposite on one side thereof, and a workpiece changer (22, 22a, 22b) which receives the workpieces (16, 16a, 16b, 16c) to be machined, such that they can be exchanged, being arranged on the other side of said workpiece retainer (11, 11a, 11b).

Abstract: The invention relates to a dental machining unit (1) having a milling chamber (10), wherein the workpiece arm (22) passes through a movement flange (24) at which the workpiece arm (22) passes through a passage wall (25) of the milling chamber (10), and that the passage wall (25) comprises a membrane (26) which permits movement of the workpiece arm (22) in at least two spatial directions and consists of a highly elastic material and particularly comprises corrugations (28).

Abstract: The invention relates to an arrangement of a machine tool (10) and a workpiece holder (111) connected to a workpiece (14), wherein the workpiece holder (111) comprises at least one surface (111a) pointing radially towards the outside, in particular a substantially planar surface, which is configured for contact with a clamping element (109) of a multi-axis workpiece arm (11) which clamping element (109) is disposed in the radial direction between the workpiece holder (111) and a chuck (120), wherein the clamping element (109) is displaceable relative to the chuck (120) for clamping and releasing the workpiece holder (111), wherein the clamping element (109) is configured to vary a clamping force (F) exerted on the workpiece holder (111) when it is displaced relative to the chuck (120).

Abstract: A dental milling machine is provided with a tool which is guided in a chuck. A workpiece arm is mounted opposite the tool to be able to be moved at least in the direction of the spindle axis. With a control device it can be moved in relation to the workpiece, especially by means of a drive motor of the workpiece arm. The workpiece arm has an abutment element, whereby the control device moves the tool and the abutment element towards each other until they abut each other. The control device can be used to detect abutment of the abutment element with respect to the tool, in particular with respect to its tip, in particular by decelerating the (relative) movement of the tool and the abutment element towards each another, upon contact of the tool and the abutment element. This position may be signaled as a reference position and, especially may be stored.

Abstract: The invention relates to a machining device for the machine-assisted production and machining of dental workpieces (16), particularly of artificial teeth and/or other dental replacement parts, the at least one workpiece (16) being clamped in at least one work-piece retainer (11) which can be raised, lowered and rotatably driven, is positioned on a rotational axis (9), and, for the purpose of machining, feeds said workpiece (16) to at least one tool spindle (4, 5, 6) that is rotationally driven and has a tool (7) secured thereto, an additional tool retainer (2, 2a, 2b) with a plurality of tools (7) arranged thereupon being associated with said workpiece retainer (11, 11a, 11b) and lying opposite on one side thereof, and a workpiece changer (22, 22a, 22b) which receives the workpieces (16, 16a, 16b, 16c) to be machined, such that they can be exchanged, being arranged on the other side of said workpiece retainer (11, 11a, 11b).