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Anti-Backlash Actuators (Metric)

Anti-backlash actuators reduce vertical backlash resulting in smooth, precise operation and minimal wear. Backlash occurs when the motor driving an actuator reverses its load direction. Since there is a gap between the lifting screw and the worm gear threads detrimental screw movement may occur. When the actuator is under load, the lifting screws’ threads are supported by the worm gears threads. The anti-backlash nut, being pinned by to the worm gear and being adjusted downwards by the shell cap, forces the bottom thread surfaces against the upper thread surfaces of the lifting screw. Thus backlash between the lifting screw and worm gear threads is reduced to a minimum.

  • The Duff Norton Anti-backlash design features a separate anti-backlash nut and reduces actuator backlash to less than 1 thousandths
  • Available in Stainless Steel 
  • Anti-backlash nuts reduce worm gear wear
  • Anti-backlash nuts act as additional load safety devices when the worm gear has become worn

Please select "Yes" at the Anti-Backlash prompt
          
Anti-Backlash Actuator Performance Specifications (Metric)
Performance Table Instructions
When reviewing any Duff-Norton Actuator Performance Specifications Table, as part of the process of selecting the best-suited actuator for your application, there are several important worm-gear ratios to consider.
  • Standard Ratio – is frequently chosen when higher speeds and efficiency ratings are desired.
  • Optional Ratio(s) – is frequently chosen when the application requires higher lifting capacities, lower speeds, or to ease the use of a handwheel.

Capacity (kN)

25

50

100

150

200

Lifting Screw

Diameter (mm)

30

38

52

58

65

Lead (mm)

6

9

12

12

12

Type

Metric Trapezoidal

Metric Trapezoidal

Metric Trapezoidal

Metric Trapezoidal

Metric Trapezoidal

Worm Gear Ratios

Std.

6:1

6:1

8:1

8:1

8:1

Optional No. 1

24:1

24:1

24:1

24:1

24:1

Optional No. 2

12:1

12:1

Travel per Worm Turn (mm)

Std.

1.000

1.500

1.500

1.500

1.500

Optional No. 1

0.250

0.375

0.500

0.500

0.500

Optional No. 2

0.500

0.750

Worm Torque at No Load (N-m)

Std.

0.56

1.13

2.26

2.26

3.39

Optional No. 1

0.56

1.13

2.26

2.26

3.39

Optional No. 2

0.56

1.13

Maximum Input Power (kW)

Std.

1.49

2.98

3.73

3.73

3.73

Optional No. 1

0.37

0.56

1.12

1.12

1.12

Optional No. 2

0.56

1.49

Worm Torque at Full Load (N-m)

Std.

23.26

62.46

128.80

208.08

302.99

Optional No. 1

10.79

29.77

69.49

111.55

162.47

Optional No. 2

14.80

40.31

Efficiency Rating (%)

Std.

17.1

19.1

18.5

17.2

15.8

Optional No. 1

9.2

10.0

11.5

10.7

9.8

Optional No. 2

13.4

14.8

Weight with 25mm Stroke (kg)

8.2

16.8

24.9

31.8

45.8

Wt per Additional 25mm Stroke (kg)

0.13

0.40

0.63

0.67

1.16

Key Torque (N-m)

80.72

213.37

579.94

943.98

1374.01

Max Worm Speed at Full Load (rpm)

Std.

612

456

277

171