Movement

1. Introduction

Movement (not:motion) can be produced in various means/ways/(manners). Historically, the following development can be observed (trraced, seen). What was realized in former times with a main drive and corresponding (pertaining, according) transmissions nowadays is totally unimaginable (no longer feasible) for (due to) reasons of economy, noise, design, accident prevention, etc. Instead (in place of) the one main drive, today, several individual drives are being used (utilized, mounted, installed, employed) directly at the places where something has to be moved.

(First thing to consider is ...) At first there is to decide (must be considered/thought) if this movement is to be generated (effectuated, [produced]) pneumatically, hydraulically or electrically. In most cases the electric geared motor represents the most economical solution beacuse (as) it can be operated (run) with a minimum of maintenance (minimized maintenance) regarding its smaller dimensions (with regard to its .../since it combines slow dimensions with a minimum of maintenance).

SEW-EURODRIVE offers in the electic geared motor program (a myriad [variety] of models) including the three-phase squirrel-cage motor with a single or several speeds as well as the DC (= direct current) motor with a shunt or a series motor in connection (conjunction, in compound, combined) with its program of geared motors. These geared motors are the most common (conventional) drives in mechanical engineering. Any (all) other electrical drives are reserved for specific applications for which often again three-phase squirrel-cage motors and DC (=direct current) geared motors are suited (can be used). Due to (considering, with regard to) the wide range (plurality) of possible drive (propulsion) solutions, several selection criteria have to be defined:

- power

- speed (single, multiple or stepless [continued] adjustment [alteration])

- regulation

- operating (operational) conditions

- maintenance

- economy

As to (as for, regarding, concerning) power and speed:

(If/ While one needs ...) In the most common power range up to about 20 kVA one, two or three speed stages are required, a normal or a pole changeable squirrel cage motor can be used. If, however, more than three speed stages or very large speed jumps are required (however), a DC gear motor will be used. At smaller speed shifts (adjustments) up to about 1:20 frequency regulated squirred-cage motors will be used; for adjustments up to 1:20 there is the possibility to use mechanically adjustable drives.

As to (as for, regarding, concerning) regulation:

If the drives are to be included in automatic control loops, either frequency-regulated drives or DC drives can be provided (designated). Frequency-regulated threephase current- (Drehstromantrieb) and DC-drives offer (have) the special (particular) benefit to obtain various (different) additional properties by means of (through, because of) their control for example such as load-independent start-up, gear-unit-protection by smoothing of start-up and braking torque, run-up after predetermined (preset, prescribed) run-up time, overload protection by means of torque and current limiting multiload operation, etc.

As to (as for, regarding, concerning) operating conditions:

Even under the hardest (most difficult/adverse) ambient conditions three-phase squirrel-cage gear motors are safe and in the long run (long-term) reliable drives (propulsions) by means of their simple construction and high types of protection. Regular maintenance provided, the DC geared motor is an ideal drive for many applications with continuous speed adjustment (stepless speed) due to a high type of protection and long brush lifetime.

As to (as for, regarding, concerning) maintenance:

A close three-phase squirrel-cage gear motor is able of operating perfectly (well) over years nearly without any maintenance [effort]. On the other hand (in contrary, in contrast, however) DC gear motors require (demand) a regular maintenance of the commutator and of the carbon brushes in relatively long intervals. Generally (altogether) it can be recommended (is recommended) to observe (stick to) the specified maintenance intervals of the bearings in both motor types, being obvious (self-evident) for a responsible operation preservation. Wearing parts and replacement (spare) parts for the motors are stored in all important industrial countries worldwide.

As to (as for, regarding, concerning) economy:

The most economical solution - small dimensions, favo(u)rable prices, high efficiency and high reliability -- will always be the three-phase squirrel-cage motor with a fixed speed. Additional features such as mechanical braking, overload protection, smooth startup or driving at different speeds can be realized with relatively small additional effort, as well. The higher initial costs of DC driven or frequency-regulated three-phase (threephase) current drives are justified by their increased comfort up to fully automatic adjustablility. Also these drivers represent (positively) definitely economical solutions for users and operators.

How is a drive projected (how to project a drive):

At first (first), load data such as (like) mass, speed, forces, switching frequencies, service life, the wheels' and shafts' geometry are gathered (collected, compiled, gleamed). With these (using)(this) data, the power requirement considering the efficiency is calculated and the output speed determined.

words:

dazugehörig - pertaining

preiswert - inexpensive, low cost, favo(u)rable, (negative: cheap = billig)

Drchführbarkeitsstudie (betreffs Finanzierung) - feasibility study