Vogel phase shifting gearboxes with torque capacities up to 1,500Nm
12 July 2010
Vogel phase shifting gearboxes provide mechanical adjustment to the phase angle of two rotating shafts. Adjustment can be made intermittently or continuously leading to widespread use for print registration, wrapping on packaging machinery and tensioning in paper making plants. Whilst many of these applications have transferred to servo technology in recent years, the use of phase shifting gearboxes is once again gaining ground as customers recognise the value of mechanical simplicity and low cost.
Phase shifting gearboxes are a variation on a planetary design where the outer ring can be rotated. It is turned by a shaft with worm gear connection to the ring. Thus rotation of the worm shaft superimposes a motion between the planetary input and output shafts, adding or subtracting a phase angle. Typically one turn of the worm shaft puts an increment of 3º on the output shaft. This fine adjustment can be used to adjust the position of a driven part of a machine, for example flight bars to feed, print cylinders for registration or knives to achieve an accurate cut length. Continuous input to the worm shaft can be used for tensioning, for example webs of paper, and a speed trim of up to ± 24rpm is possible.
Two configurations of these phase shifting gearboxes are available with details available and a catalogue download on the Techdrives website. In-line gearboxes can be 1:1 or have a 3:1 reduction ratio and are available in five sizes for torques 50 to 1,500Nm. Right angle gearboxes incorporate a bevel output stage with twin output shafts and gear ratios of 1, 2 or 3. An additional use for these gearboxes is found in emergency or pony drives.
For example with ovens and furnaces, it is often necessary to remove products from the heated areas should the main drive fail, perhaps due to an mains supply fault. Here a manual input to the adjustment shaft, or perhaps an air motor, allows the output to be turned slowly and with a low power requirement. The main drive to the input shaft does not turn as it may be locked against back-driving.
Contact Details and Archive...