New Vista’s patented Thread-Verification Units (TVUs) and related products are supplied in a variety of configurations, but they all perform the same function: to drive, at high speed, a gage probe into, through, or onto a threaded production part; and to reverse back out again, thus providing 100% assurance of assemblability. These Units will work with both internal and external threaded features. With the proper TVU, “GO”, “NO GO”, Combination, and variable gaging, are all possible.
A high-response servomotor drives the gage probe. In between the motor and the probe is a low-inertia torque limiter that permits the gage to stall harmlessly in wrong-size, wrong-pitch, short, incomplete, or damaged threads; or when the features are excessively out of square or out of position. Also in the drive is a compression compensating mechanism, which allows the spindle to retract harmlessly in case the thread is missing, or if a threaded hole has a broken tap in it. This feature prevents damage to both the drive and the piece part. In cases like this the probe will harmlessly spin at the entrance of the hole. Any of these events will cause built-in sensors to signal a reject.
To back the probe out of the hole, the TVU’s drive reverses at full torque; this is to ensure that the gage exits the part even if it has just jammed in a tapered or damaged thread.
New Vista TVUs have been proven in numerous high production applications. These Units are now employed all over the world for checking threads in nut manufacturing plants, stamping facilities, die casting plants and the like.
New Vista’s thread-verification products (and Off-Axis/Angular Adapters) are covered by U.S. Patent 7,059,055, or are in patent-pending status.