bnp-b2365(eng)b.pdf - 第244页

4. Servo Adjustment 4 - 45 (2) Collision detection method 2 When the current comman d reaches the motor's ma ximum current, the moto r will decelerate and stop at a torque 80% (standard value) of the moto r's m…

4. Servo Adjustment

4 - 44

4-6-3 Collision detection

Collision detection quickly detects a collision of the motor shaft, and decelerates and stops the motor.

This suppresses the generation of an excessive torque in the machine tool, and helps to prevent an

abnormal state from occurring. Impact at a collision will not be prevented by using this collision

detection function, so this function does not necessarily guarantee that the machine tool will not be

damaged or that the machine accuracy will be maintained after a collision. The same caution as during

regular operation is required to prevent the machine from colliding.

(1) Collision detection method 1

The required torque for the command is estimated from the position command issued from the NC,

and the disturbance torque is obtained from the difference with the actual torque. When this

disturbance torque exceeds the collision detection level set with the parameters, the motor will

decelerate to a stop with a torque 80% (standard) value of the motor's maximum torque. After

decelerating to a stop, alarm 58 or 59 will occur, and the system will stop.

The collision detection level for rapid traverse (G0) is set with SV060: TLMT. The collision

detection level for cutting feed (G1) is set to 0 to 7-fold (SV35.clG1) based on the collision

detection level for rapid traverse. When clG1 is set to 0, collision detection method 1 will not

function during cutting feed. If SV060 is set to 0, all collision detection (including methods 1 and 2)

will not function.

Collision detection level setting parameter Detected alarm

During rapid traverse

(During G0 feed)

SV060 Alarm 58

During cutting feed

(During G1 feed)

SV060 × c1G1 (SV035) Alarm 59

Alarm detection range for collision detection method 1

CAUTION

The collision detection function does not guarantee safety or machine

accuracy when a collision occurs. Thus, the same caution as during regular

operation is required to prevent the machine from colliding.

Speed command

(r/min)

Estimated torque

(stall%)

3000

200

100

-200

-100

-3000

Unbalance torque

(SV032)

G0 collision detection

level (SV060)

Collision detection method 1,

detection range

(alarm 58/59)

Frictional torque

(SV045)

G1 feed

(

cuttin

feed

)

G0 feed

(

id traverse

)

G1 collision detection

level

(

SV060×clG1

)

4. Servo Adjustment

4 - 45

(2) Collision detection method 2

When the current command reaches the motor's maximum current, the motor will decelerate and

stop at a torque 80% (standard value) of the motor's maximum torque. After decelerating to a stop,

alarm 5A will occur, and the system will stop. If the acceleration/deceleration time constant is short

and incorrect detections easily occur during normal operation, lengthen the acceleration/

deceleration time constant and adjust so that the current is not saturated (does not reach the

maximum current) during acceleration.

If the acceleration/deceleration time constant cannot be lengthened, set parameter SV035/bitF

(SSF4.c12n) to 1 to ignore collision detection method 2.

POINT

1. Always validate SHG control when using the collision detection function, or

when carrying out SV059 setting value operation.

2. Provide an allowance in the detection level setting to prevent incorrect

detections.

3. All collision detection functions will be disabled when SV60 is set to 0.

4. Collision detection method 2 will function if a value other than 0 is set in

SV060. Note that the detection can be ignored by setting the parameter

(SV035/bitB).

5. The torque estimated gain (SV059) must be readjusted when there are

changes in the detector resolution following the detector replacement, or in

the detector loop gain (PGN) or position control system. (closed loop control

and semi-closed loop has been changed).

[1] Confirm that SHG control is active. Collision detection function is valid only during SHG control.

[2] Set the axis unbalanced torque to the torque offset (SV032: TOF). (Refer to "4-3-5 (1)

Unbalance torque and frictional torque" for details on measuring the unbalance torque.)

[3] Measure the frictional torque and set in the frictional torque (SV045: TRUB). Carry out

reciprocation operation (approx. F1000) with the axis to be adjusted, and measure the load

current % when the axis is fed at the constant speed on the NC SERVO MONITOR screen.

This frictional torque is expressed with the following expression.

[4] Set SV035: SSF4.clt (bitF) to 1 for the axis being adjusted, and move in both directions with

JOG, etc., at the rapid traverse rate. When the MPOS display on the NC SERVO MONITOR

screen has stabilized, set that value for the torque estimated gain (SV059: TCNV). Return

SV035: SSF4.clt (bitF) to 0.

[5] If the acceleration/deceleration time is short, and the current is limited, set SV035: SSF4.c12n

(bitB) to 1 to invalidate collision detection method 2.

[6] Adjust the collision detection level (SV060: TLMT). First set 100. If operation at the rapid

traverse rate results in an alarm, increase the setting value by approx. 20. If an alarm does not

occur, lower the setting value by approx. 10. When SV035: SSF4.clet (bitA) is set to 1, the

estimated disturbance torque peak value for the latest two seconds will appear at MPOS. This

value can be used as reference. Set the final setting value to a value approx. 1.5-fold the limit

value at which an alarm does not occur.

[7] Divide the maximum cutting load with the value set for the collision detection level (SV060:

TLMT). (Round up the decimal) Set this value in SV035: SSF4.clG1 (bitC-E).

(+ feed load current %) - (- feed load current %)

Frictional tor

(

)

4. Servo Adjustment

4 - 46

No. Abbrev. Parameter name Explanation Setting range

SV032 TOF Torque offset

Set the unbalance torque of vertical axis and inclined axis. -100 to 100

(Stall current %)

SV035 SSF4 Servo function

selection 4 F E D C B A 9 8 7 6 5 4 3 2 1 0

clt clG1 cl2n clet cltq iup tdt

bit Meaning when "0" is set Meaning when "1" is set

Set the retracting torque for collision detection in respect to the maximum

torque of the motor.

cltq

00 : 100% 01 : 90% 10 : 80% (Standard) 11 : 70%

A clet

Setting for normal use The disturbance torque peak of the

latest two seconds is displayed in

MPOS of the servo monitor screen.

B cl2n Collision detection method 2 valid Collision detection method 2 invalid

clG1

Collision detection method 1

Set the collision detection level during cutting feed (G1).

The G1 collision detection level=SV060

× clG1.

When clG1=0, the collision detection method 1 during cutting feed won’t

function.

F clt

Setting for normal use The guide value of the SV059

setting value is displayed in MPOS

of the servo monitor screen.

SV045 TRUB

(Low

order)

Frictional torque

When you use the collision detection function, set the frictional torque. 0 to 100

(Stall current %)

SV059 TCNV Collision detection

torque estimating

gain

Set the torque estimating gain when using the collision detection function.

After setting as SV035/bitF(clt)=1 and performing

acceleration/deceleration, set the value displayed in MPOS of the NC

servo monitor screen.

Set to "0" when not using the collision detection function.

-32768 to

32767

SV060 TLMT Collision detection

level

When using the collision detection function, set the collision detection

level during the G0 feeding.

If "0" is set, none of the collision detection function will work.

0 to 999

(Stall current %)