This machine tests a small valve, part of the vapor canister system, for pressure decay. The photo showing the nest "in the white", before black oxide coating, illustrates the basic nest design.

In operation, the operator places a valve to be tested in the nest, and touches the optical buttons to start the cycle. the part is first inserted, under power, into the test block, which is made of high quality tool steel, properly heat treated then polished to correctly seal against the o-rings on the part being tested. Pressure and vacuum are alternately applied to the part, and pressure decay over time is measured. The difference in pressure being utilized here is less than 1 psi. The part must be energized, as it would be in the vehicle, to accomplish the test. This is facilitated by automatically extending a plug probe, with live leads, into the part socket while it is locked in the nest.

The machine uses a full-box design, for safety, and a power-driven pneumatic front door, which closes at the start of cycle, to maintain operator safety. Very sophisticated pneumatic circuitry and devices were used in the construction, and it is of course PC controlled. Two identical machines were built, to maintain production volume, as the test necessarily contains some time delays, to adequately measure the phenomenon is question.

This is a test machine, and performs a number of different functions simultaneously. After the unit to be tested - a small motor, with attached plugs and capacitors - is placed in the nest, the operator places their right and left hands on the optical touch buttons on either side of the table, in the front of the machine, and the test procedure begins. First, the large slide-mounted probe on the left is extended, and the pins on the front of it enter the large plug on the part assembly. The pins inside the plug are checked for uniform height, and to see if any are bent. If all pins are straight, and of the same height, they will depress the spring-loaded contact pins on the front of the dark block on the slide, and a laser emitter sends a beam of light through a series of match-drilled holes in the rear body of the pins, within the larger dark block, which seals out outside light. If all the pins are straight, and of uniform height, they will depress the hardened steel contact pins to a uniform depth in the black block they are mounted in. This will align a series of holes drilled through the pins with one drilled through the block as well. A laser emitter will send a beam through this hole in the block, to a receiver on the other side of the block. If the beam is detected by the receiver, this means all pins were straight, and of uniform height. Should the part be acceptable at this phase of the test, current is then passed though the spring-loaded pins, to check for continuity and shorts in the circuits attached to the four pins inside the main part socket. If this test is passed, the next step is authorized. Should faults be detected, they are specifically displayed by various labeled lights on the face of the panel, readily visible and easily read by the operator.

The circuit energizing the two-pin fixed block seen in the front is powered up. If both pins inside this part plug are straight and of uniform height, this will trigger the current to turn on in that connecting block, and continuity and shorts are also checked for in this part circuit. The continuity and short tests are performed by momentary currents applied to the test blocks. If the second test, of the two pins, is acceptable, the current is now turned on for several seconds, powering up the motor. If the motor shaft is spinning in the correct direction, the worm gear attached to the output shaft of the motor will spin a small rubber-covered wheel, which comes in contact with the worm gear when the part is locked in the nest, causing the rubber wheel to move along it's shaft, and send a signal to a proximity switch, which tells the machine the motor is spinning in the correct direction. Should the motor spin in the wrong direction, the wheel stays in it's home position, and after a small discreet time delay, a specific fault signal is displayed on the panel face, telling the operator the motor assembly is a reject, and why. In the case of any fault occurring at any point in the test procedure, the fault is specifically indicated at the time it is detected, whereupon the operator terminates that part's test cycle, the machine releases the part, resets itself for the next test, and the operator disposes of the part in the prescribed manner.

The smaller station to the right. on riser legs, is used to test a larger style motor, for continuity and correct direction of rotation. The motor is simply dropped, worm gear shaft up, into the delrin socket nest seen on the base platform. The motor's two wire leads, one white and one black, are placed on their respective brass contact strips, seen on the right of the station. The clamp is then closed, with a non-conductive, spring-loaded micarta disc now gently keeping the wires electrically in contact with the brass strips. Current is then applied across the circuit, and at this time the cylinder-mouted orange rubber wheel seen on the upper right of the station is extended, contacting the motor's worm gear. The motor is now powered up, and direction of rotation, and current draw are checked, assuring both meet specifications.

This machine has been in use for several years now, and still performs it's intended functions flawlessly. No major parts have ever been replaced. The machine is very operator-safe, and easy to use. It has never been modified from it's original design, that design proving highly satisfactory to the intended purpose, and very reliable. The machine is essentially a table-top unit, and is supplied with an optical two-hand anti-tie-down safety system, and third-person guarding.