Now construction is one of the most expensive branches of the national economy. It is shown on set of categories of resources, especially human and financial. In other words, in the course of construction of any house, the building or construction irrespective of its functional purpose the manual work which is not possible for mechanizing at the moment is always required.
Despite the last achievements in the field of the equipment and production, for obtaining necessary result certain completion is always necessary. Completion of some operations for which the simplest tools are required means. Nevertheless, introduction of the advanced automated equipment, including electric drive of direct current, every day becomes more and more active.
Modern electrodrive systems are separated into two groups on the following parameters:
1) on driving force;
2) by the name of their main component.
If such component is absent, then the functionality of system of the electric drive is completely excluded.
There are electric engines of alternating current which are divided into asynchronous and synchronous, and the devices transforming direct current to rotational motion of the corresponding mechanism. Each kind of the electric drive has the pluses and minuses.
Alternating current is not direct current. It means that tension in electrical circuit can change considerably in the indicators, beginning from very modest and finishing with impressive parameters. Therefore devices which work is carried out at the expense of such electricity have, to tell kind of, "unbalanced character".
In other words, electric motors of alternating current because of features of the moment both start, and braking, not in all cases are convenient in operation. Also they are not capable to create torsion torque with the smooth course. In addition, electric motors of alternating current have exterior, quite big weight and the impressive sizes, characteristic of them, that brings certain difficulties at their repair and regular technical maintenance.
As for electric drives of direct current, they are used already for a long time. Such devices have found broad application practically in all branches of the national economy. Since day of the birth, electric drives of direct current gradually began to win new fields of activity of the person, especially construction, the industry, agriculture and many others.
Therefore at people enough experience and knowledge concerning use and repair of devices of this sort was during this time accumulated. It also is the main argument when it is required to replace faulty and also outdated driving component of the electric drive. At the same time instead of the engines working at alternating current install electric motors of direct current.
In what advantages of the electric motors working at direct current? It is first of all the small size, small weight and ability to create the smoothest, without any sharp breakthroughs the course necessary for rotation of work element of the electric drive. One more their advantage is use of various principles of electromecanics. For example, in case of sharp increase in load of wave of rotation the quantity of turns of the corresponding mechanism gradually decreases that has allowed to use electric motors of direct current in building sectors absolutely new, uninvolved before.