The use of intricate tooling is required when manufacturing multi-cavity, high-precision automotive components. However, automation on its own was not sufficient to increase capacity within the cmm services because on-machine measurement within the cmm services created a bottleneck. The company was successful in eliminating the backlog that frequently occurred in the tooling department as a result of their decision to incorporate a CMM into the automated cell. More than a century ago, the company started out as a division of Briggs and Stratton. These days, however, it is known as Strattec, cmm inspection services and it is in the business of designing, developing, manufacturing, and marketing mechanical locks, electronically enhanced locks and keys, and ignition lock housings. The manufacturing facility required an upgrade in order to effectively produce these intricate parts. Having a working relationship with Premier Machine Tool Midwest (located in Hartland, Wisconsin). This automation solution moves along a rail to feed multiple machines and makes use of the company's WorkShopManager software, which integrates all of the machining and measuring processes into a single workflow. After some time had passed, a Makino U32J wire EDM was put in place. The facility was built to function around the clock with no lights on at any time.
Despite this, Strattec was dissatisfied with the amount of time required to finish a batch once the machine was fully operational. The CNC machines were given the task of locating the component rather than actually machining it, and the operators spent a significant portion of their days preparing the pieces to be run overnight. The company decided to install a Brown Sharpe One shopfloor coordinate measuring machine (CMM) made by Hexagon Metrology (North Kingstown, Rhode Island) in order to alleviate the bottleneck and improve the inspection quality. Its primary purpose is to locate electrodes and workpieces on their pallets before feeding them to the EDMs, and it does this before each pass through the machine. Because it is so dirty, it cannot be inspected by the CMM until it has been cleaned, during which both the dirt and the lubrication are removed. The part is then transferred by the robot to the coordinate measuring machine (CMM) so that the required compensation for spark gaps and the offsets for the X, Y, Z, and C (rotation in the X-Y plane) coordinates on electrodes can be determined. Workpieces are examined to determine the X, Y, Z, and C offsets that they have.
When it is finished, it is taken back to the CMM so that it can be inspected. The data collected by the CMM is then imported into PC-DMIS, the flagship software of Hexagon Metrology. PC-DMIS features an extensive library of macros that are specifically designed for the die-making industry. Instead of relying on the witness measurement, which is taken at the electrode's base, the offline toolset for electrodes takes into account the true burning geometry of the electrode. These intricate measurements can be finished in a matter of minutes with a degree of precision that is superior to that which can be achieved using the conventional witness method of inspection. The process of programming is no longer a time-consuming and laborious one in which electrodes are measured on a sinking machine. Following the installation of the CMM, the same batch of electrodes can be inspected at a rate that is at least fifty percent faster than before, all while the EDM is working on other parts. In addition, cmm services the current method of toolmaking eliminates the need for manual intervention in the data entry process. According to the company, thanks to the improvement in quality, the tooling department now knows whether or not electrodes are good before sinking them into the steel.
Additionally, because of the accuracy of a CMM, every part that is removed from the cmm services is inspected with greater precision and does not require the presence of the operator. Even more time has been freed up for us as a result of the CMM integration—probably somewhere between 30 and 40 percent of the total. Because we had implemented our Brown Sharpe One CMM, we were able to provide all of the others with increased levels of efficiency. Craig Broetzmann, the leader of the CNC team at Strattec, claims that he is certain that if the cmm services had not been configured in its current state, it would have been impossible to achieve that accomplishment."In the past, a rush job would force us to drop everything and shift to that project," he says. "Nowadays, we have the ability to prioritize our work more effectively."The tasks that previously required anywhere from two to four days to complete are now typically completed in a single day. The group is able to make modifications to the instrument and then resample almost immediately without having to wait for a response from another department. The automated cmm services has presented the facility with additional opportunities to explore.