6 POSITIONING CONTROL

6.23.12 Home position return by the limit switch combined type(1) Limit switch combined type

The proximity dog is not used in this method. Home position return can be executed by using the external upper/lower limit switch.

When the home position return is started, it travels to direction of home position return with "home position return speed". Deceleration is made by turning the limit switch of home position return direction ON to OFF, it travels to reverse direction of home position return with creep speed, and the zero point just before limit switch is home position.

(2) Home position return by the limit switch combined type

Operation of home position return by limit switch combined type for setting the limit switch in the home position return direction is shown below.

 

Acceleration time

 

Deceleration time

1) It travels to preset direction of home

 

 

 

 

position return with the home

 

 

 

 

 

Home position

V

Home position

position return speed.

return speed

2) A deceleration stop is made by the

 

 

return direction

1)

 

 

 

 

 

external limit switch ON to OFF.

 

 

 

 

 

 

 

 

 

 

 

 

3) After a deceleration stop, it travels to

 

 

 

 

 

 

reverse direction of home position

 

 

 

 

 

2)

return with the creep speed, and the

 

 

 

 

 

home position return ends with the

 

 

 

 

 

 

zero point just before limit switch.

 

 

 

 

 

 

 

 

 

 

Home position

3)

 

 

 

 

 

 

 

 

Home position

 

 

 

 

return start

 

 

Creep speed

External limit switch

(Indicates with normally closed contact)

Zero point

The travel value in this range is stored in the

monitor register "travel value after proximity dog

ON".

The travel value in this range is stored in the monitor register "home position return re-travel value".

Fig. 6.43 Home position return operation by the limit switch combined type

(3) Home position return execution

Home position return by the limit switch combined type is executed using the servo program in Section 6.23.16.

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