Automatic College Bell (AT89S8252 & DS1307)
This Project takes over the task of Ringing of the Bell in Colleges. It replaces the Manual Switching of the Bell in the College. It has an Inbuilt Real Time Clock (DS1307) which track over the Real Time. When this time Equals to the Bell Ringing time, then the Relay for the Bell is switched On.The Bell Ringing time can be Edited at any Time, so that it can be used at Normal Class Timings as well as Exam Times. The Real Time Clock is displayed on four 7-segment display. The Microcontroller AT89S8252 is used to control all the Functions, it get the time through the keypad and store it in its Memory. And when the Real time and Bell time get equal then the Bell is switched on for a predetermined time.
The GO! is an entirely hands- and tool-free, self-adjusting support that is designed for applications that do not require rigid fixed height support. It comes factory standard with the correct height standoffs and is drop-in ready. No air lines, controls or switches are needed. Once placed in the machine, support tooling becomes worry-free.
Design Benefits
- Board Sag
For many manufacturers, board sag is the major process issue with board support. Excessive sag can cause component misplacement, machine error and throughput reduction. The GO! comes from the factory preset at the tooling height of the machine. Providing sufficient support while forming to the contour of bottom-side parts, the GO! supports the board at its flat position. - Component Damage
Incorrect placement of fixed height support tooling can damage underside components as well as cause micro fractures that may not be evident during inspection. However, the GO!'s resistive support design virtually eliminates the risk of component damage. - Board Bounce/Vibration
Vibration and bounce caused by the placement nozzle can introduce placement defects and misregistration. As components become smaller and boards become thinner, the impact on placement accuracy is magnified by board bounce. Add to that a less forgiving lead-free reflow self-alignment and errors increase significantly. The GO! dramatically reduces bounce and vibration, resulting in higher yields and accuracy.
The GO! is the only board support solution that is able to remove board sag and reset for each board. It combines the board sag removal of fixed height tooling pins with the automation of a reset style support and the bounce/vibration dampening of locking-style compliant board supports.
