A depth thread plug gauge is a device that can measure the size of the thread and the depth of the thread, both in a single go. Conventionally, to measure the depth of a thread, external instrumentation is required which consumes extra time. This device removes the need for external attachment that saves time and is more convenient to use.
The new design comes with an additional adjustment to make the traditional thread plug gage able to measure depths as well. The design involves three basic parts: (i)Thread (ii)Body (iii)Cover.
The cover can freely translate as well as rotate over the body. The cover has main scale inscribed on it, and the body has the Vernier scale. In the neutral position, the zeroes of both the scales align with each other, and the tip of the thread coincides with the cover bottom surface. When the thread moves into the hole, the body moves along with it but the cover remains steady. This relative motion between body and cover gives the depth reading on the scale.
Measurement of thread size and depth
The taps can be detached from the body and vice versa with the use of locking mechanism to use various tap sizes with single device. The cover can be locked at its position after inserting the thread completely, to take the reading after disengagement.