3.6.07 MC_GearIn

Version 2.1 by xingzhi lin on 2025/12/04 20:10

Set the gear ratio between the slave axis and the main axis, perform the electronic gear operation.

Instruction format

Instruction	MC_GearIn (FB)
Name	Disconnect gear function block
Graphical performance		ST performance
		MC_GearIn( Master: =, Slave: =, Execute: =, RatioNumerator: =, RatioDenominator: =, Acceleration: =, Deceleration: =, Jerk: =, BufferMode: =, InGear=>, Busy=>, Active=>, CommandAborted=>, Error=>, ErrorID=>);

Related variables

Input and output variables	Name	Data type	Effective range	Initial value	Description
Master	Master axis	AXIS_REF_SM3	-	-	Mapped to an axis, i.e. an instance of AXIS_REF_SM3
Slave	Slave axis	AXIS_REF_SM3	-	-	Mapped to an axis, i.e. an instance of AXIS_REF_SM3

Input variables	Name	Data type	Effective range	Initial value	Description
Execute	Execution	BOOL	[FALSE, TRUE]	FALSE	Rising edge signal execution instruction
RatioNumerator	Gear ratio molecule	DINT		1	Gear ratio molecule
RatioDenominator	Gear ratio denominator	UDINT		1	Gear ratio denominator
Acceleration	Acceleration	LREAL		-	Specified acceleration
Deceleration	Deceleration	LREAL		-	Specified deceleration
Jerk	Jerk	LREAL		-	Jerk
BufferMode	Cache mode selection	MC_BUFFIR_MODE	0 to 5	0	Specify the action when multiple instances start a motion instruction 0: Abort 1: Wait 2: Blend at low speed 3: Blend at previous speed 4: Blend at the next speed 5: Blend at high speed

Output variables	Name	Data type	Effective range	Initial value	Description
InGear	Gear ratio reached	BOOL	[FALSE, TRUE]	FALSE	TRUE, target velocity is reached from axis
Busy	Execution flag	BOOL	[FALSE, TRUE]	FALSE	TRUE, the instruction is being executed
Active	Control	BOOL	[FALSE, TRUE]	FALSE	TRUE when controlling
CommandAborted	Abort	BOOL	[FALSE, TRUE]	FALSE	TRUE, interrupted by other control instructions
Error	Error	BOOL	[FALSE, TRUE]	FALSE	When an error occurs, set to TRUE
ErrorID	Error ID	SMC_ERROR	Refer to SMC_ERROR	0	When an error occurs, the error ID is output.

Function description

Specify an action target axis by Slave .Specifying RatioNumerator, RatioDenominator, Acceleration, and Deceleration, and performing gear operation;
The instruction position, the feedback position, and the latest instruction position can be specified for the Master (master axis);
Execute rising edge starts electronic gear action;
After starting the operation, the Slave axis takes the speed obtained by multiplying the Master axis speed by the gear ratio as the target speed, and performs acceleration and deceleration operation;
To uncouple the electronic gear after executing GearOut instruction must be passed;
This instruction is a speed electronic gear function, and the loss of synchronization distance caused during acceleration will not be automatically compensated;
When Busy signal is TRUE during instruction execution, if the target speed of the slave axis does not reach the new rising edge of Execute will not affect it;
When the Busy signal is TRUE during instruction execution, if the target speed of the slave axis reaches this time, the new rising edge of Execute will not affect it;
The target velocity is reached, InGear is TRUE, after which Slave axis movement=master axis movement*RatioNumerator/RatioDenominator;
If the master axis speed changes in real time, carefully use this instruction.

Precautions

Please do not use the MC_SetPosition instruction during the execution of the instruction to avoid accidents caused by rapid operation of the motor;

When you want to use MC_SetPosition insturction for Master, disengage the relationship between the spindle and the slave axes and execute the instruction.

Sequence diagram

Busy becomes TRUE at the same time as Execute is started. Active becomes TRUE in the next cycle. When the target speed is reached, InGear (gear ratio reached) becomes TRUE.

When this instruction is aborted with another instruction, CommandAborted becomes TRUE and Busy, Active, InGear becomes FALSE.

To end the electronic gear action halfway, use MC_GearOut or MC_Stop instruction.

(1) This instruction starts in other instruction execution

Start this instruction for the currently executing instruction, which can be switched or cached to this instruction.

The action at launch of multiple instances of this instruction is specified by BufferMode.

Buffer mode selection	Description
Aborting	Immediately abort the currently executing instruction and switch to this instruction. When the operation direction of the axis is reversed due to the instruction switching, the operation direction of the axis is reversed according to "operation at the time of reverse" in the axis parameter.
Buffered	The function block is started immediately after the last instruction motion is terminated. No blending is done here. When the end condition (Done, InVelocity, InEndVelocity, InGear, InSync, EndOfProfile, etc.) is reached, the new motion starts at the speed of the previous motion. If the previous motion was MC_MoveAbsolute or MC_MoveRelative, the new motion starts at still.

(2) Other instructions in execution of this instruction are enabled

Multiple instances of execution of instructions in an interrupted manner from the slave axis can be initiated.

At this time, the gear operation is stopped, and the operation started by a plurality of instances is started.

The instruction cannot be launched in multiple instances without interrupting.