5.12 Holding Brake
5.12.1 Brake Operating Sequence
5-32
5.12
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.
5.12.1
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 times required to brake 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 times required to brake on the actual equipment before using the
application.
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 Servomotor
that is already stopped.
Prevent
s
the moving
part from falling due to
gravity when the power
s
upply i
s
OFF.
Moving part of machine
Holding brake
Prevent
s
the moving part from
moving due to an external force.
External force
S
ervomotor
Moving part of machine
S
haft with External Force Applied
Holding brake
Vertical Axi
s
S
ervomotor
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
OFF
OFF
*1
*2
0
*1
*3
Motor
s
peed
Po
s
ition/
s
peed reference
Brake contact
s
ection (lining)
/BK (Brake Output)
s
ignal
Motor power
s
tatu
s
S
ervo ON/OFF
s
tatu
s
S
ervo ON
Power
s
upplied.
ON
S
ervo OFF
Power not
s
upplied.
Brake applied.
Brake applied.
Brake relea
s
ed.
Power not
s
upplied.
S
ervo OFF