Precision for machine tool drives

Example: ServoFit® PHQA planetary gear unit.
Top gearing quality gives a backlash of < 1 – 1.5 arcmin.

Quality is also a question of use of resources

For reliable and durable use in metalcutting machine tools, planetary gear units must be highly rigid in design and flawless in manufacture.

STÖBER is at the forefront worldwide for the manufacture of planetary gear units in this category.

The reason for its leader position is mainly its in-depth experience over many decades in the manufacture of gear units with high-precision helical gearing.

Quality is the result of in-house manufacture

The manufacture of high-quality gear units demands full control of all the production processes. Hence all the STÖBER units are made at its headquarters in Pforzheim. From cutting of all the components to assembly and 100% inspection.

Only the best for machine tools

Precision metal-cutting machine tools become ever more productive and precise from machine generation to machine generation. Highspeed cutting and heavy-duty machines make very heavy demands on the drive axes.

Column boring mill

The gear units from STÖBER provide the right answer with new standards of drive engineering for these modern machine tool manufacturing requirements.

Dynamic rapid traverse, continuous jerk free movements with instantaneous responses with variable loads are typical of the requirements for the metal cutting machine tools.

STÖBER is a very high profile global supplier of top quality, helical planetary servo gear units.

Vertical lathe

Whereas costly special gear units often used to be required to meet customer requirements, the STÖBER planetary gear units now offer a cost-effective alternative without sacrificing any of the machine performance.

Current issues play a part, such as energy efficiency and noise emissions which for a gear unit always have to be considered in combination with the gearing quality. Planetary gear units from STÖBER naturally come with the highest specifications based on continuously optimised in-house manufacturing standards.

STÖBER is one of the pioneers of helical planetary gear units and as market leader confirms its position over and over again as a developer and innovator of these units in machine tool manufacture.

Head start through innovation

Boring and milling machining centre

The practicality of STÖBER’s innovative developments is based on everyday proximity to machine tool customers.

This brochure for machine tool manufacturers combines tried and tested and new, innovative gear unit series, rack and pinion drives and ball screw drives to give an overview.

The potential offered by the new STÖBER drive standards can best be discussed in a conversation between experts.

ServoFit® PHQA Size 11 and ServoFit® PHQ Size 7

Gear ratios of up to i = 600:1 can be achieved with three-stage ServoFit® planetary gear units

These high gear ratios or reductions enable the torque requirement to be obtained with smaller size motors.

So designers of heavy metal-cutting machines can adjust the moment of inertia to perfection.

Quality for high-end machine manufacture

ServoFit® planetary gear units are suitable for very high and maximum feed axis quality standards.

Due to the extremely rigid construction and high STÖBER manufacturing quality level of the ServoFit® helical planetary gear units, they have earned a special place in machine tool manufacture. They stand out for their:

ServoFit® PHQ 10 planetary gear unit, 2-stage Quattro system with ME motor adapter and EasyAdapt® motor coupling

Cross-sectional view: The output stage has 4 planet gears (Quattro system). The input stage has the standard 3 planets

• Jerk-free operation even at very low feed rates
• High positioning accuracy even at fine adjustment moves
• High efficiency
• Low noise development
• Maximum dynamics (high-speed cutting)
• Torsional rigidity (top quality of surface finish)

Helical planetary gear units with extremely robust housings

The PH/PHA/PHQ/PHQA series differ mainly by their backlash and accelerating torque limits.

The modular STÖBER system offers these products in right angle-solutions as PH(Q)K and PH(Q)KX.

The option of multi-stage gear configurations means that very high gear ratios and corresponding accelerating torques can be achieved. The configuration options available allow designers of heavy metal-cutting machines to adjust the moments of inertia to perfection.

The drives can be installed in any position – all gear units are maintenance-free and filled with high quality synthetic oil.

Motor adapter system

ME motor adapter with EasyAdapt® coupling

Motor installation takes barely a minute with the ME motor adapter. Mounting errors are prevented by the precise centring of the servo motor. Friction locking with the integral EasyAdapt® coupling is produced by a single clamping screw.

Optimised flange shaft for maximum power density

With right angle planetary gear units, extreme gear ratios of up to i = 591:1 can be achieved

The flange shaft has external and internal centring. The number of holes on the housing flange and in the flange shaft is designed for transmission of the emergency stop torque.

ServoFit® PH(A) planetary gear unit

Designed for high and very high machine tool manufacturing requirements such as reliability and torsional and tilting rigidity.

• Gear unit sizes: PH(A)3 – PH(A)10
• Gear ratio: 4 – 100
• Accelerating torque: 50 – 7,500 Nm
• Backlash PH: = 3 – 4 arcmin
• Backlash PHA: = 1 – 2 arcmin

ServoFit® PHQ(A) planetary gear unit Quattro system

These gear units have four planets. This gives an increase in torque of up to 35% for the same size. Combined with the lowest possible backlash – even at extreme gear ratios – these mount-on gear units are unique.

• Gear unit sizes: PHQ(A)7 – PHQ(A)10 – PHQ11
• Gear ratio: 18 – 600
• Accelerating torque: 950 – 22,000 Nm
• Backlash PHQ: = 3 arcmin
• Backlash PHQA: = 1 – 1.5 arcmin

ServoFit® PH(Q)K right-angle planetary gear unit

Highly rigid drive unit consisting of an SMS bevel gear unit at the input and a PH planetary gear unit with a robust bearing system for high tilting and torsional rigidity at the output.

• Gear unit sizes: PH5K1 – PH10K6 - PHQ7K2 – PHQ11K8
• Gear ratio: 16 – 561 (22 – 591)
• Accelerating torque: 320 – 7,500 Nm (451 – 22,000 Nm)
• Backlash PHK: = 3.5 – 4,5 arcmin
• Backlash PHQK: = 3.5 – 4 arcmin

ServoFit® PHKX right-angle planetary gear unit

Drive unit consisting of a compact KX right-angle gear unit at the input and a PH planetary gear unit with a robust bearing system at the output. Extremely torsionally rigid and precise for small spaces.

• Gear unit sizes: PH3KX3 – PH10KX8
• Gear ratio: 4 – 300
• Accelerating torque: 50 – 7,500 Nm
• Backlash: = 3 – 6 arcmin

The new output bearing housing puts an end to oversized drives

With the new output bearing housing and the new pinion/gear/flange interface configuration, all specification sizes have been significantly improved.

The feed force was previously limited by the maximum permissible tilting moment of the gear unit bearings.

The new output bearing housing lightens the load on the output bearings in the planetary gear unit. The lower tilting moment enables a smaller gear unit size to be used and a smaller motor to be fitted. The choice can now be made based on rated and accelerating torque requirements.

The output bearing housing increases the linear stiffness

The outboard support of the output bearing housing increases the linear stiffness of the drive as a whole by a factor of 1.5 to 2.5. With this system to protect against high-frequency process vibration, HighForce ZTRS drives are ideal for increasing the feed force and processing quality of high-performance machine tools.

The innovative flanged pinion – less torque – more precision

Due to the special shape of the pinion with integral flange, the number of teeth can be determined independently of the flange shaft on the gear unit.

The smaller pinion generates less torque.
The shorter lever reduces linear backlash.
The pinion concentricity can be set at < 10 µm.

Supply as a complete gear unit/pinion/rack system

STÖBER supplies the complete mechanical solution with motor adapter and coupling (type depends on gear unit) for connection to all common makes of servo motors for machine tool manufacture.

Precision racks from ATLANTA

With two rack classes (UHPR and UHP), STÖBER offers a complete ATLANTA rack range for very high specifications in machine tool manufacture. In addition to the helicaltoothed racks, straight-cut racks are also available.

The top professional range for machine tool manufacture

HighForce ZTRS PH(A) rack and pinion drives come in four sizes with gear ratios of i = 4:1 to i = 600:1. Pinion models without support pins for a one-sided bearing arrangement are also available.

The feed force ranges from 14.5 to 124 kN.

• Construidos en brida ISO compatibles con reductores del mercado.
• Desde módulo 2 a módulo 8
• Disponibles en diente recto y helicoidal
• Construidos en clase/calidad Q5 y Q4
• Fuerza de empuje hasta 100.000N

Conjunto Z TRS PH(A)

Dos empresas especializadas en accionamientos se unen para proponer soluciones optimizadas para máquina-herramienta.

• Conjunto de reductor piñon cremallera optimizados para muy alto par
• Juego lineal reducido aproximadamente al 50%
• Rigidez lineal de la reductora aumentada hasta 100%
• Engrase por piñón de fieltro integrado (opción)
• Relación entre masas de inercia optimizada
• El rodamiento adicional (soporte TS) permite utilizar los reductores al límite de su par nominal sin importar el par de vuelco.