Mitsubishi Electronics MR-J2S- CL Dog type home position return, Signals, parameters

4. OPERATION

4.4.2 Dog type home position return

A home position return method using a 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)Signals, parameters

Set the input signals, parameters and program as follows:

Item	Device/Parameter used	Description
Manual home position return	Automatic/manual selection (MD0)	MD0 is switched on.
mode selection
Dog type home position return	Parameter No.8	0 :Dog type home position return is
		selected.
		Refer to Section 4.4.1 (2) in this section
Home position return direction	Parameter No.8	and choose home position return
		direction.
Dog input polarity	Parameter No.8	Refer to Section 4.4.1 (2) in this section
		and choose dog input polarity.
Home position return speed	Parameter No.9	Set speed until detection of dog.
Creep speed	Parameter No.10	Set speed after detection of dog.
		Set when shifting the home position
Home position shift distance	Parameter No.11	starting at the first Z-phase signal after
		passage of proximity dog rear end.
Home position return		Use the acceleration/deceleration time
acceleration/deceleration time	Parameter No.41
		constants set in parameter No. 41.
constants
Home position return position	Parameter No.42	Used to set the current position on
data		completion of home position return.
	Select the program including the "ZRT"
Program	command that executes a home position
	return.

(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 (4.2) and (4.3):

L1			V		td		(4.2)
						..............................................................................
		60			2
L1
		: Proximity dog length [mm]
V		: Home position return speed [mm/min]
td		: Deceleration time [s]
L2		2		S			(4.3)
L2		: Proximity dog length [mm]
	S	: Moving distance per servo motor revolution [mm]

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