Device for determining the end of the processing time for hardening masses
Assignee3M Espe AG
InventorsGerd Brandhorst, Hermann Nirschl, Marc Peuker, Ingo Wagner
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Abstract
A device is provided which determines the end of the processing time for hardening masses, in particular dental molding masses. The device comprises a display unit and a sensor unit which record the change in at least one of the rheological properties of the mass. A method that can be used with such a device is described.
Claims14
A device for monitoring the setting profile of hardening compounds, comprising a mixer-shaft motor with a control, a mixer shaft, a seat for a cartridge, which can be connected to a dynamic disposable mixer which is used to mix the hardening compound, a display unit and a sensor unit, which can record the change in at least one of the rheological properties of the compound, the sensor unit being coupled to the mixer-shaft motor, and the disposable mixer cooperating with the sensor unit.
The device as claimed in one of the preceding claims, in which the sensor unit is chosen from:
- capacitors, ultrasound sensors, pH electrodes, torque transducers, quartz oscillators, thermoelements, current meters, voltage meters, resistance meters, wire strain gages and/or force transducers.
The device as claimed in one of the preceding claims, in which the display unit can output a visual and/or acoustic signal.
The device as claimed in one of the preceding claims, in which the sensor unit can record the change in the torque applied to the mixer shaft.
A method comprising the following steps:
- a) mixing a hardening compound in a dynamic disposable mixer which is driven by a mixer-shaft motor, b) dispensing almost all of the compound from the dynamic disposable mixer, c) recording the change in at least one of the rheological properties of the mixed compound which remains in the dynamic disposable mixer via a sensor unit, d) outputting a signal as soon as the value of the change from step c) has reached a predeterminable threshold value, the sensor unit cooperating with the mixer-shaft motor.
The method as claimed in claim 7, in which at least step c) is performed with a device as claimed in one of claims 1 through 6.
The method as claimed in one of claims 7 and 8, in which, in step c), a change in the torque applied to the mixer shaft can be recorded.
The method as claimed in one of claims 7 through 9, in which the measurement in step c) is pulsed.
The method as claimed in one of claims 7 through 10, in which the measurement in step c) takes place with a speed of rotation which is smaller than the speed of rotation which is used in step a) for mixing.
The method as claimed in one of claims 7 through 11, in which the mixer shaft is not fully rotated during the measurement in step c).
The use as claimed in claim 13, in which the hardening compound is a dental impression compound.
The use of a dynamic disposable mixer for mixing, dispensing and subsequently monitoring the setting profile of hardening compounds.
Dependencies are inferred from the claim text.