Stöber PH Planetary Gearboxes in XL Size
With the fourth generation of the PH series, Stöber presents extremely precise planetary servo gearboxes, which are the largest on the market in their performance class. In addition to their high precision, they are also energy-efficient. Stöber also offers a variant as a servo gearmotor.

Image 1: PHQEZ Series: Servo Gearmotor, particularly distinguished by its innovative 4-planet system.
Planetary gearboxes are the highest class of gear units. Stöber Antriebstechnik GmbH + Co. KG has been a specialist in this field for nearly 40 years. These components feature a compact design and can transmit high torques, as forces are distributed across multiple gears, unlike conventional gearboxes. With the current planetary gearboxes, the drive specialist introduces the fourth generation in large sizes. They can be combined with compact synchronous servo motors of the EZ series and mounted directly. Without an adapter, the mass moment of inertia is lower, and the drive is more dynamic. Using Stöber’s motor adapters, all suitable motors from other manufacturers can also be connected to the gear series. For this purpose, adapters are available with various couplings, as well as with an integrated brake in the ServoStop version. Thanks to the very large motor plate in the Large version, the user can mount motors with very large constructions. If necessary, PH gearboxes are also available with an angular drive step.

Image 2: Extremely compact PHV gearbox in size 9 with a motor adapter, enabling the connection of all suitable motors from other manufacturers.
Stöber designed the fourth generation of its PH gearboxes to be up to 100 millimeters shorter than the previous version. This has a positive effect on stiffness and mass inertia. The new gearboxes also require less mounting space, are lighter, and in some cases offer about 20% more torque – and also 50% higher tilting torque.

Image 3: Fourth generation combined with ZTR and ZTRS gear drives: High-performance gearmotors, ideal for use in machine tool feed axes.
The excellent quality of the housing and gears increases acceleration torque by up to eleven percent, as well as improving accuracy and running precision. Additionally, there is very high tilting stiffness. Stöber has enhanced parameters such as power density and torsional stiffness, and expanded or more generously dimensioned planetary gearboxes for certain ratios. The planetary gearboxes and sun gears also use state-of-the-art materials and hardening processes, as well as lifetime lubrication with synthetic gear oil. As a result, the new series of gearboxes is incredibly stable and durable, making servicing and repairs virtually unnecessary.

Image 4: Stöber’s range includes drive controllers, gearmotors, and cables – providing everything from a single source.
With a gear ratio range from 12 to 600, the new PH gearboxes are especially versatile. In addition to the standard PH version, Stöber also offers the Quattro design. The PHQ series, with the four-planet system, is also highly precise thanks to high-quality worm gears and offers even greater torsional stiffness. The user also benefits from maximum torque. Upon request, Stöber also combines the fourth generation with ZTR and ZTRS gear drives. This provides high-performance gearmotors, for example, for use in machine tool feed axes. Due to their high efficiency, the new planetary gearboxes are sought after wherever size, precision, economy, and performance are key factors.