Situation: We have a new machine that has a Mits FX2N Plc and a MRJ2S servo amp and a FX-1PG "pulse generating module".
Servo motor is geared to a weld wheel on a spot welder. Process is started and a part is fed onto the wheel and at certain angles, the welder welds.
Problem: The machine when started goes into a home positioning sequence that rehomes its self with a dog. During this homing process, the welder is welding at predetermined angles. As the wheel is rotating, there is another flag that trips the dog and resets the encoder back to 0. The FX-1PG will only reset the encoder when it is in this rehoming process. The wheel has to go in one direction. This obviously increases the encoder count. What I want to be able to do is not go through this rehoming process and reset the encoder whenever I want to. Problem lies in the flag hitting the prox does not always stop in same position all of the time.
The weld points are set up to weld between 0 and 18000 on the encoder. The other 180 degrees on the wheel is set up the same way. One revolution of the weld wheel makes two parts. The PLC code is set up to look at the encoder value and compare to the welding point positions. The wheel is turing too fast to accuratly stop at the same point when it hits the prox, "dog". Slowing the speed down is not an option.
I know the QD75M positioning module has a MD 20 that works the way I need this too work. I want to reset the encoder data after the wheel turns 180 to start the process back at 0 for the next part. If I issue a command to the servo to go to 18000, I want to be able to turn on the welder at 500, 1000, 10000, etc. If I do not go through the rehoming process each part the encoder keeps increasing.
Any suggestions?
Need more info let me know.
Thanks
Tim
Servo motor is geared to a weld wheel on a spot welder. Process is started and a part is fed onto the wheel and at certain angles, the welder welds.
Problem: The machine when started goes into a home positioning sequence that rehomes its self with a dog. During this homing process, the welder is welding at predetermined angles. As the wheel is rotating, there is another flag that trips the dog and resets the encoder back to 0. The FX-1PG will only reset the encoder when it is in this rehoming process. The wheel has to go in one direction. This obviously increases the encoder count. What I want to be able to do is not go through this rehoming process and reset the encoder whenever I want to. Problem lies in the flag hitting the prox does not always stop in same position all of the time.
The weld points are set up to weld between 0 and 18000 on the encoder. The other 180 degrees on the wheel is set up the same way. One revolution of the weld wheel makes two parts. The PLC code is set up to look at the encoder value and compare to the welding point positions. The wheel is turing too fast to accuratly stop at the same point when it hits the prox, "dog". Slowing the speed down is not an option.
I know the QD75M positioning module has a MD 20 that works the way I need this too work. I want to reset the encoder data after the wheel turns 180 to start the process back at 0 for the next part. If I issue a command to the servo to go to 18000, I want to be able to turn on the welder at 500, 1000, 10000, etc. If I do not go through the rehoming process each part the encoder keeps increasing.
Any suggestions?
Need more info let me know.
Thanks
Tim