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.

A non-contact tool setting apparatus, suitable for use with machine tools and the like, is described in which a transmitter emits light that is received by a receiver. An analysis unit is provided for analysing the light received by the receiver and generating a trigger signal therefrom. The receiver includes an imaging sensor, such as a CMOS or CCD sensor, having a plurality of pixels. The analysis unit generates the trigger signal by analysing the light intensity measured by a first subset of the plurality of pixels. This analysis may involve, for example, determining a resultant received light intensity or performing edge detection. The non-contact tool setting apparatus can thus emulate the operation of a laser based non-contact tool setting apparatus whilst also permitting imaging of cutting tools.

A position measurement method to measure a position of an object in a machine tool includes a tool sensor position acquisition stage, a reference block position acquisition stage, a relative position calculation stage, a reference tool position acquisition stage, a position measurement sensor measurement stage, a length compensation value calculation stage, and a position measurement stage. In the position measurement stage, the measurement position of the object is compensated using a length direction compensation value of a position measurement sensor calculated in the length compensation value calculation stage. The object is measured by the position measurement sensor installed to a main spindle.

An error identification method includes a tool sensor position acquisition stage, a reference block position acquisition stage, a relative position calculation stage, a reference tool position acquisition stage, a position measurement sensor measurement stage, a length compensation value calculation stage, a diameter compensation value acquisition stage, a position measurement stage, a position compensation stage, and a geometric error identification stage. The diameter compensation value acquisition stage acquires a radial direction compensation value of the position measurement sensor with the measured jig. The position measurement stage indexes the rotation axis to a plurality of any given angles and measures respective positions of the measured jig. The position compensation stage compensates the position measurement value at the position measurement stage using the length direction compensation value and the radial direction compensation value. The geometric error identification stage identifies the geometric error from the plurality of position measurement values.

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.

The present invention provides a device (10) for inserting a tool (18) into a tool receptacle (14), said device comprising a first holding means (12), which is configured to hold a tool receptacle (14), a second holding means (16), which is configured to hold a tool (18), a linear guide (20), by means of which the second holding means (16) is able to move in relation to the first holding means (12) in an axial direction running along or parallel to a main axis (X) in order to move the tool closer to the tool receptacle and insert it into the tool receptacle, a sensing arrangement (40), which is able to move in an axial direction and is configured to sense in a contact-free manner an axial position of a first reference point (R1) associated with the first holding means and to sense in a contact-free manner an axial position of a second reference point (R2) for a tool held by the second holding means, and a measuring arrangement, which measures an axial displacement path of the sensing arrangement. The invention furthermore relates to a method for inserting a tool as well as a device having a clamping arrangement for holding the tool.

A depth gauge device including a body extending a central longitudinal axis and including a channel and a light-passing hole, the light passing hole open to the channel, a light source mounted in the body for generating a light beam, the light beam passing through the light-passing hole toward a surface of a drill-bit extending through the channel, the light beam forming an incident light beam when reflected away from the drill-bit surface, an image sensor mounted in the body for sensing the incident light beam and generating a plurality of successive images of the drill-bit surface to detect variations in the position of the drill-bit moving through the channel and an clamp coupled to the body, the clamp including a plurality of adjustable arms configured to clamp the device to a protection sleeve.

A method for measuring a tool, a method for mounting a tool in a tool holder, a screen, a computing unit with such a screen and a presetting device and/or shrinking device with such a screen, and uses of a screen for measuring a tool. A method for measuring a tool using a screen by providing a display screen; and measuring the tool by way of the display screen. A tool measuring device having a display screen configured for measuring a tool. The display screen can have a measuring scale wherein the tool is measured by the measuring scale.

A measuring sleeve for measuring a tool, a tool presetting device, a method for measuring a tool by means of a tool presetting device and to a method for mounting a tool in a tool holder. The measuring sleeve for measuring a tool provides a base body, particularly in the form of a sleeve, with a recess which runs starting from a first end side of the measuring sleeve in the axial direction of the measuring sleeve and has cross sections, in particular circular cross sections, decreasing in steps for receiving a tool to be measured.

A measuring sleeve for measuring a tool, a tool presetting device, a method for measuring a tool by means of a tool presetting device and to a method for mounting a tool in a tool holder. The measuring sleeve for measuring a tool provides a base body, particularly in the form of a sleeve, with a recess which runs starting from a first end side of the measuring sleeve in the axial direction of the measuring sleeve and has cross sections, in particular circular cross sections, decreasing in steps for receiving a tool to be measured.