SMC Corporation LECSA series, Руководство по эксплуатации

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13. POSITIONING MODE
13.6.3 Dog type home position return
This is a home position return method using the proximity dog. With deceleration started at the front end of the
proximity dog, the position where the first Z-phase signal is given past the rear end of the dog or a motion has
been made over the home position shift distance starting from the Z-phase signal is defined as a home position.
(1) Devices and parameters
Set the input devices and parameters as follows.
Item Device/Parameter used Description
Home position return mode
selection
Automatic/manual selection
(MD0)
Turn MD0 ON.
Point table No./Program No.
selection 1 to 3
(DI0 to DI2)
Point table method: Select the home position return mode
by turning OFF DI0, DI1 and DI2.
Program method: Select a program that has the home
position return "ZRT" command.
Dog type home position return Parameter No. PE03 0: Dog type home position return is selected.
Home position return direction Parameter No. PE03
Refer to section 13.6.1 (2) and select the home position
return direction.
Dog input polarity Parameter No. PE03
Refer to section 13.6.1 (2) and select the proximity dog
input polarity.
Home position return speed Parameter No. PE04 Set the speed till the dog is detected.
Creep speed Parameter No. PE05 Set the speed after the dog is detected.
Home position shift distance Parameter No. PE06
Set when shifting the home position starting at the first Z-
phase signal after passage of proximity dog rear end.
Home position return acceleration
/deceleration time constants
Parameter No. PE07
Set the acceleration/deceleration time constants during a
home position return.
Home position return position data Parameter No. PE08 Set the current position at home position return completion.
(2) Length of proximity dog
To ensure that the Z-phase signal of the servo motor is generated during detection of the proximity dog
(DOG), the proximity dog should have the length which satisfies formulas (13.1) and (13.2).
L
1
60
V
2
td
                                        
(13.1)
L
1
: Proximity dog length [mm]
V : Home position return speed [mm/min]
Td : Deceleration time [s]
L
2
2
ΔS
                                          
(13.2)
L
2
: Proximity dog length [mm]
ΔS : Travel distance per servo motor revolution [mm]