Single-Ratio Transmissions

Single-Ratio Transmissions

Single-Ratio Transmissions

First and foremost is the knowledge of the company KLOSE-Antriebstechnik, that ensures that the durability of the gearbox in heavy applications does not depend solely on the torque rating. Gearboxes (as well as motors, especially as direct drives) have greater durability when used in this way because shocks that occur due to short-term blocking or hard reversing are taken into account. These impacts put a particular strain on the shafts in terms of bending, the gearing in terms of breaking, and the rolling elements in the load area in terms of compression.

Part of the KLOSE concept of the gearbox + motor is that their robust housing and all covers are made of thick-walled cast iron. Our models allow casting in gray cast iron (quality EN-GJL-250) or nodular iron (up to quality EN-GJS-600). On request, the components are also available in a welded design or as a combination of both.

According to the requirements in the plants of the rolling mill and metallurgical industry, the gears, shafts and bearings are generously dimensioned to withstand the impacts that occur there. For switching and reversing operations, the safety in relation to the torque is designed to be robust.

Splash lubrication is used to lubricate the gear wheels and high-speed shafts. The roller bearings of the output shaft are lubricated for life via large chambers, but can also be refilled via a grease nipple.

Single-stage KLOSE gears + motors are available with reductions from 1.73 to 6.06 (or 7.57, which is not included in the table). Standard gear ratios for single-stage gearboxes are listed in the table below. Of course it is possible to realize customer-specific requirements. As an individual manufacturer, the company gemota manufacture any translations (including individual gear pairs) that fit into the existing housing. However, the maximum permissible typical torque for each gear size named in the table remains. In addition, the former company KLOSE Antriebstechnik has 12 single-stage housing sizes starting with the S63-1A up to the S252-1A. Torques from 80Nm to 6,700Nm can be achieved.


The basic version of gears is with foot (B3) and with a solid shaft for the clutch. However, other versions of gears and motors are also possible with interchangeable parts for the KLOSE models. In particular, the slip-on version (H3) with a horizontal motor position, or the version with bevel gear stage (H5) suspended at an angle below should be mentioned. By using the bevel gear as a set of gears, the translation naturally increases (in the range of a two-stage gearbox).

It is possible to manufacture these gearboxes with hollow shafts for direct mounting (see explanations for gearboxes with hollow shafts, with their own description).

Other mounting forms, e.g. for vertical assembly, horizontal position or directly flanged gearboxes can be manufactured on customer request. With the variety of housing sizes and a wide variety of attachment versions, these gearboxes also offer good conditions as a replacement for gearboxes that are no longer available. The company gemota specializes in maintaining the existing gear connection in a system with the KLOSE gearboxes. As a result, changes in the system (e.g. a new roller table frame) are often not required.


Overload Protection

Repeated higher demands on a gearbox and motor due to borderline torques, blockages or very frequent reversing lead to increased temperatures, especially in the motor.
The safest protection against destructive overloading is therefore monitoring the temperature development in the motor itself. See thermal winding protection for the motors.

Tachos, Encoders

If the drive needs to record the current speed of the material on the roller table, a tachometer can be mounted on a second shaft end if required. If the material is to be positioned in a targeted manner on the roller table, a pulse generator is attached. Advantageously, however, the speedometer / encoder is on the engine to increase the accuracy of the measurement through the translation of the gearbox


If the material is to be positioned and held with a gear + motor, a brake can also be attached on request. An additional shaft end is also used for this purpose. Drum brakes or spring-loaded disc brakes are used. Advantageously, however, the brake is located on the motor in order to increase the force even more through the translation of the gearbox