Unique Bearings Earn an “A” in Circuit Board Testing Equipment
Checksum’s Analyst machine applies multiple probes to test the connections on the surface of computer circuit boards. The machine’s very light, spring-loaded contacts are mounted in a custom platen, which is accurately positioned by a scissor mechanism to ensure that its hundreds of test points are heavily loaded on the appropriate areas of the circuit boards. The Checksum engineers’ challenge was to find bearings that would operate in an oscillatory motion and carry a peak load of 2,700 pounds, with a minimum bearing life of 500,000 cycles. Corrosion resistance, maintenance-free life, low cost and ease of installation were also important.
Checksum had tried traditional ball bearings in its initial prototype, but they had failed. Not surprisingly, two of Spyraflo’s unique bearings passed the test with flying colors. The machine’s complete scissor mechanism is held in place by four 0.750”-diameter, PTFE-composite bronze, pillow block bearings. In addition, four self-clinching 0.375” diameter PTFE-composite bronze bearings are securely mounted into the arms of the assembly carrying the extreme load associated with elbows of the scissor mechanism. The self-clinching process eliminates risk to the bearing’s internal diameter during installation and ensures a secure, permanent fit that won’t come lose during operation. Checksum’s Analyst machines — and our bearings inside them — are now being used by circuit board manufacturers in 40 countries.
We offer bearings in press-fit, self-clinching, or mounted configurations, with plain or rolling elements, in a variety of materials. Bearings come in standard inch and metric sizes — including miniature options.