Tool Monitoring Sajjad Ahmadpoor Amirkabir University of Technology

Tool wear describes the gradual failure of cutting tools due to regular operation. It is a term often associated with tipped tools, tool bits, or drill bits that are used with machine tools. crater wear in which contact with chips erodes the rake face.

Tool Monitoring Methods Didect: In the direct method the tool directly measured And to directly monitor and so wear directly measured Which are divided into some methods… Tool Monitoring Methods Indirect: the indirect method of measuring parameters, some parameters that connected with wear rate such as temperature, cutting forces, vibration and ultrasonic waves are measured. in this case, some factors are depend on machining process such as temperature, strain, acoustics, vibrations and cutting forces. and some other factors back to the motors. the wear is monitored with their changes.

Probing systems for CNC machine tools: Inspection probes for machining centers are typically located in a tool carousel and are interchanged like conventional tools. On lathes, the probe is typically a semi-permanent feature of a rotating turret. In both case, signaling between probe and CNC generally has to be remote. For tool setting applications, typically the probe is mounted in a fixed location, thereby allowing direct communication between probe and CNC. Optical probes use four main types of transmission systems: Radio Inductive Direct or ‘hard-wired’

Optical transmission systems: · Optical machine module (OMM) · Machine interface unit (MI12) · Optical machine interface (OMI) · Optical machine interface (OMI-2/OMI-2C) An optical transmission system uses infra-red technology for communicating between the probe and the CNC controller. OMM OMI

Radio transmission systems: A radio transmission system provides long range (up to 15 m path length) of communication between the probe and the machine’s controller. The system hops between channels, within the designated frequency band. The use of unique identifiers allow multiple radio systems to operate in close proximity. · Machine interface (RMI)

Inductive transmission systems : Inductive transmission works by passing power and probe signals across a small air gap between two induction modules. Typically, a probe fitted with an inductive transmission system comprises the following: · Probe and inductive probe module (IMP) · Machine module (IMM) · Machine interface unit (MI5)

Hard-wired transmission systems : A hard-wired probe system has the simplest form of transmission system and typically, comprises the following elements: · Signal cable · Machine interface unit (MI8)

Applications: CNC machining centre and milling machine inspection CNC machining centre tool setting and breakage detection CNC lathe and grinder inspection CNC lathe tool setting

Lathe Tool presetting: the quicksetter automatically sets the values of the work coordinate and the tool offset registers quicksetters can also measure the size of tools before cutting starts check for tool wear, damage or breakage during the machining operation

Lathe Tool presetting:

Touch Probes for Tool Measurement: Together with the measuring cycles of the CNC control, the tool touch probes enable to measure tools automatically while they are in the machine spindle. The control saves the values measured for tool length and radius in the central tool file. By inspecting the tool during machining you can quickly and directly measure wear or breakage to prevent scrap or rework. If the measured deviations lie outside the tolerances, or if the monitored life of the tool is exceeded, the control can lock the tool or automatically insert a replacement tool.

Measuring tool length and radius with stationary or rotating spindle

Laser Systems for Tool Measurement: Tool monitoring with a laser system is a very flexible solution. The contact-free optical measurement enables you to check even the smallest tools rapidly, reliably and without collision. Even the most sensitive tools are completely secure from damage.