01 |
Overview of Electromagnetic Brake Motor |
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02 |
Electromagnetic Brake of Non-excitation Run Type |
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① Structure and Operation Principle
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(Fig. 1) in the right side shows a structural diagram of the electromagnetic brake motor.
Our Electromagnetic Brake Motor is an RNB type, and when the coil is charged with voltage, the armature repressed
by the spring is sucked in to push the spring, making a gap between the armature and the brake lining, and with
release, making braking power for the motor shaft freely rotate.
② Characteristic of Electromagnetic Brake
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This is the electromagnetic brake of AC non-excitation run type and can be connected directly to the motor. When the power source is turned off, the motor stops instantaneously and the load is maintained. The retention force is 2 kgf · cm ~ 10 kgf · cm. This type of brake is best suited if a safer brake is required when the power is turned off, because the retention force is maintained when the power turns off.
③ Braking Time Difference by Connection Method
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The connection can be made as shown in (Fig. 2). However, the method shown in (Fig. 3) is also possible if a simpler connection metho is sought for. In case of (Fig. 3), the braking time takes longer roughly by 50msec than that of (Fig. 2), resulting in the increase overrun. This is because the braking action lags about 50msec by the magnet even after the brake's excitation is vanished, because the magnetic energy of the motor can act on the excitation winding of the electronic brakes's magnet when the braking takes place.
Voltage |
Size (mm) |
Output (w) |
Frequency (Hz) |
Ampere (A) |
Input (W) |
Brake (kg.cm) |
Torque (N.m) |
Single-phase 110V/220V |
60 |
6 |
50/60 |
0.031 |
3.1 |
2.0 |
0.20 |
70 |
15 |
Single-phase 110V/220V Three-phase 220V |
80 |
25 |
50/60 |
0.054 |
5.4 |
4.0 |
0.40 |
90 |
40 |
50/60 |
0.100 |
10.0 |
10 |
1.00 |
60 |
90 |
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03 |
Operating Time and Braking Characteristics |
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GDM2 =
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[kgf·cm2] |
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= |
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=1.1[kgf·cm2] |
NG = |
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= |
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=0.08 revolution (28.8˚) |
GENERAL SPECIFICATION OF BRAKE MOTORS
① Example Take K8RG25NC-B as an example and let it be combined with K8G30B to drive the inertia body (GDL2 = 1000kgf·cm2). To calculate the operating time, braking time, and overrun under the power source frequency of 60Hz, first convert the load's inertia moment to the motor shaft as follows. GDL2 : Fly wheel effect of load [kgf·cm2] GDM2 : Fly wheel effect at motor shaft [kgf·cm2] I : Ratio of gearhead The inertia moment expressed in Sl unit can be calculated by the following expression. g : 9,80665[m/s²]
② OVER RUN As shown in (Fig. 5), the overrun of the motor shaft is NM ≒ 2.5 revolutions. Hence, the gearhead's output shaft has the overrun as follows.
③ Operating Time and Braking Time
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As shown in (Fig. 5), the operating time t1 ≒ 130[msec], and the braking time t2 ≒ 170[msec].
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The operating time of the brake motor is a total sum of the motor's operating time and the electronic brake's open time. Thus, if the electronic brake is left open in advance, the motor can be started quickly.
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It is advised that the bake should be open at least 10msec before the motor starts operating.
Item |
Specification |
Insulation Resistance |
100MΩ or more when 500V megger is applied between the windings and the housing after rated motor operation under normal ambient temperature and humidity |
Dielectric Strength |
Sufficient to withstand 1500V at 50/60Hz applied between the windings and the case after rated motor operation under normal ambient temperature and humidity for 1 min. |
Temperature Rise |
class A (65℃) or class E (75℃)or class B (85℃)or less increase measured by thermometer after rated operation |
Insulation Class |
Class E(120℃), Class B(130℃), UL approval motor class A (105℃) |
Overheat Protection Device |
Built-in thermal protector (automatic return type) : Open 130℃±5℃ Close 82℃±15℃ |
Ambient Temperature |
-10℃~50℃ |
Ambient Humidity |
85% maximum (non condensing) |
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