TECHNICAL FIELD The invention relates to the field of mechanical engineering, tool engineering and may be used as a mechanical transmission.

BACKGROUND OF THE INVENTION

From the viewpoint of its essential features the most similar to the applied invention is a widely used type of mechanical transmission, chosen as a prototype. These are toothed gear of direct contact and a chain gear. The chain gear consists of two gear wheels - star gears positioned on the parallel main shaft and driven shaft, and connecting them with an infinite chain. The chain gears are used in machine tool stations, vehicles (bicycles, motorcycles and transporters), agricultural and other machines. As it is known from the literature, the main advantages of the chain gears are the following:

- possibility to use at significant axle spacing (up to 8 meters);

small dimensions against belt gearing;

constant gear ratio;

high coefficient of efficiency;

- less shaft load against belt gearing;

possibility to transmit rotation to several shafts, and even those with opposite direction of rotation, by means of one chain.

The drawbacks of chain gears are the following:

- stretching of the chain as a result of wear in joints;

- the necessity of thorough assembly and service (greasing, adjustment, clearing of shaft misalignment);

- some transmission velocity fluctuation especially at small numbers of teeth and large pace;

- useless of the gear at need of periodical reverse without breaks. The toothed gear consists of two wheels on the surfaces of which gashes and lugs-teeth interchange. The advantages of the toothed gears are:

- constant gear ratio;

reliability and durability;

compactness;

- wide range of transmitted power (from deciles to the tens of thousands kilowatt) at practically any rotation velocities;

- high coefficient of efficiency;

- light pressure on the shafts and bearings.

To the drawbacks of toothed gears must be referred:

the necessity of high accuracy of production and assembly;

- noise at working on significant velocities;

inability of stepless change of transmission number.

AIM OF THE INVENTION By means of combination of elements of two gear types in one toothed gear, the invention achieves positive effect aimed to:

increase the coefficient of efficiency;

increase reliability at reduced objectives to the accuracy of production and assembly of the gear;

- increase durability and compactness;

avoid inevitable stretching of the chain as a result of wear in joints;

- reduce pressure on shafts and bearings;

avoid the necessity of thorough assembly and service (greasing, adjustment, clearing of shaft misalignment);

- applicability of the gear when the periodical reverse without breaks is needed;

decrease dimensions;

provide smooth running and constant gear ratio;

decrease operation noise at significant velocities. DISCLOSURE OF THE INVENTION

(Novelty, inventive level)

For the achievement of the said targeted aim in the toothed gear consisting of two wheels 1, positioned on the parallel main shaft and driven shaft 5, on the surface of one wheel there interchange gashes and at least one-rowed lugs-teeth 7, but on the surface of another wheel there interchange at least two-rowed side lugs 2 with axes 4 that are parallel to the shaft axis 5, on which the rollers 3 forming kinematic rotating pairs (joints) are positioned. One wheel with interchanging gashes and lugs-tccth may be performed in a form of a star. The surface of another gear may have two-rowed side lugs 6 with the interchanging axes 4, parallel to the shaft axis 5, on which the rollers 3 are positioned. The number of rows with lugs-teeth in the multiple-rowed toothed gears is one less than the number of rows with lugs on which the rollers arc positioned. The rollers may have cylindrical, conical, barrel-like or hyperbolic form.

The essence of the invention is explained in drawings representing the following:

Fig.1 represents toothed gear, wherein on the surface of at least one wheel there interchange gashes and two-rowed side Jugs with axes that are parallel to the shaft axis, on which the rollers arc positioned.

Fig. 2 represents toothed gear, wherein on the surfaces of both wheels there interchange gashes, and at least two-rowed side lugs with the axes, parallel to the shaft axis, on which the rollers are positioned.

Fig.3 represents toothed gear, wherein on the surface of at least one wheel there are two-rowed side walls - curbs with interchanging axes which are parallel to the shaft axis and on which the rollers are positioned. The toothed gear according to the said distmguishing features is embodied in the following way:

If the centres of the shafts of two toothed wheels approach to each other, so that the teeth of one wheel enter into the gashes of the other wheel and bring into motion the main shaft of, said, the wheel with one-rowed teeth, than the tooth of a wheel positioned on the said shaft with its side (face) surface (profile) will touch the surface of the roller positioned on the axis of the lug of another driven wheel and pressing on the roller will make the last, and therefore the wheel and the driven shaft turn. At such action of the tooth on the roller there originates a link connection, which differs from the regular interaction between teeth at toothed transmission, which includes bringing sliding pressure on the teeth of the driven shaft.

Due to provision of mechanical transmission by means of kinematic rotating pair (tooth-roller) the positive effect in the invention is achieved.