5.11 Holding Brake
5.11.1 Brake Operating Sequence
5-31
5
Basic Functions That Requir
e Setting befor
e Operation
5.11
Holding Brake
A holding brake is used to hold the position of the moving part of the machine when the SER-
VOPACK is turned OFF so that moving part does not move due to gravity or an external force.
You can use the brake that is built into a Servomotor with a Brake, or you can provide one on
the machine.
The holding brake is used in the following cases.
5.11.1
Brake Operating Sequence
You must consider the brake release delay time and the brake operation delay time to deter-
mine the brake operation timing, as described below.
*1.
Rotary Servomotors: The brake delay times for Servomotors with Holding Brakes are given in the following
table. The operation delay times in the following table are examples for when the power supply is switched on
the DC side. You must evaluate the actual brake delay times on the actual equipment before using the applica-
tion.
•
The brake built into a Servomotor with a Brake is a de-energization brake. It is used only to
hold the Servomotor and cannot be used for braking. Use the holding brake only to hold a Ser-
vomotor that is already stopped.
•
The /BK signal will remain ON during overtravel. The brake will not be applied.
Vertical Axis
Servomotor
Holding brake
Prevents the moving part from
falling due to gravity when the
power supply is OFF.
Moving part of machine
Shaft with External Force Applied
External force
Moving part of machine
Servomotor
Holding brake
Prevents the moving part from
moving due to an external force.
Important
Brake Release Delay Time
The time from when the /BK (Brake) signal is turned ON until the brake is actually released.
Brake Operation Delay Time
The time from when the /BK (Brake) signal is turned OFF until the brake actually operates.
Term
*1
*2
0
*1
*3
/S-ON (Servo ON) signal
OFF
Power not
supplied.
OFF
Brake applied.
ON
Power supplied.
ON
Brake released.
OFF
Power not supplied.
OFF
Brake applied.
Motor power status
/BK (Brake) signal
Brake contact section
(lining)
Position/speed reference
Motor speed