The gears with flanks in arc of circle are well known (the holes part in the wheel and the full part in the pinion).

These gears have the disadvantage that they need a high precission machining.

The procedures for the achievement of the gears with NOVICOV teeth (with arc of circle profile) are well known; they consist in teething the wheel by means of a cutter in order to achieve the holes in the wheel and with another cutter we make the teeth with arc of circle profile on the pinion.

These procedure have the disadvantage that they request complicated mechanical machining operations with high casts and high precision.

The problem which appears at the achievement of the gears consists in the appearance of some clearances or blocks between the flanks because of the dimensional tolerances of the processing tools.

The problem has been solved with a gear consisting of wheels which have holes on the circumference, obtained by dividing the teething ; in the holes we mount rollers on one of the wheels (pinion).

In order to maintain the rollers in their pockets we use side caps which are fixed axially by safety rings (of ZEGER Type).

In another achievement version the gear is provided with tubular rollers instead of cylindrical rollers, which permit the functioning even in case the wheel axis are not rigurously parallel.

In another achievement version the gear consists of two parallel gears displaced with helf of a pitch. The rollers are cylindrical or tubular.

The procedure for the achievement of the gear consists, according to the invention, in manufacturing the rollers without teething, which are placed on the divider of the teething machine with the dividing circles tangent.

In the tangent point along the common generator we make a hole, achieving equal pockets in both wheels.

The invention presents the following advantages: -it permits the taking over of the axial tolerances from processing and mounting ; -it has a low cost; -it does not request a high precision.

Further we achieve by dividing, all the holes which form the teeth.

The invention will be shown further on in connection with the figures 1-14, which represent the following : -Fig. 1, section through the wheels assembly; -Fig. 2, frontal view of the gear ; -Fig. 3, frontal view of the gear with all pockets achieved; -Fig. 4, section after plan A-A, acc. to fig. 3 through the gear ; -Fig. 5, axial section through the gear assembly; -Fig. 6, section after plan B-B, acc. to fig. 5 through the gear; -Fig. 7, section through the gear in other achievement versions ; -Fig. 8, section through the gear ace. to fig. 7 after plan C-C ; -Fig. 9, axial section through the gear in other versions -Fig. 10, section in plan D-D, acc. to fig. 9 through the gear; -Fig. 11, axial section through the gear in another achievement version ; -Fig. 12, section E-E through the gear according to fig. 11 : -Fig. 13, axial section through the gear in the last achievement version ; -Fig. 14, section after plan F-F, according to fig. 13.

The gear shown in fig. 5 and 6, according to the invention, consists of the wheels 1 and 2 provided with pockets a distributed uniformly on the wheel 1 and 2 circumference in order to allow the arrangement of cylindrical rollers 3, maintained in the pockets a by means of some caps 5. The caps 4 are fixed axially by means of elastic rings 5 (ZEGER type).

According to the invention the gear consists, in other achievement versions, shown in the figures 7 and 8, of the same constructive elements like the gear in the first version, unlike the fact that instead of cylindrical rollers 3 are used tubular rollers 6 in order to permit to take over the angle tolerances due to manufacturing and mounting.

According to the invention, in other achievement versions shown in fig. 9 and 10 the gear consists in two parallel gears 7 and 8, fixed according to each case.

A first assembly of wheels 7 and 8 is displaced with half of a pitch.

The displaced parallel gears provide the increase of the covering degree.

In this case of gear we use cylindrical rollers for the parallel gears, as well as side caps 4 fixed axially with safety rings 5.

The limit of axial displacement of the rollers 3 at the inside is given also by the caps 4.

According to the invention, in other achievement versions shown in the figures 11 and 12, the gear consists of the same components like the gear shown in fig. 8,10 unlike the fact, that instead the cylindrical rollers 3 are used tubular rollers 6, like in the case of the gear shown in the fig. 7 and 8.

The gear of the last achievement version, shown in the figures 13 and 14, consists of the same components like the gear in fig. 5 and 6, unlike the fact that instead of the cylindrical rollers and the side caps 4 we use a chain of GALL-type.

The achievement procedure of the gear according to the invention consists in the manufacturing of two wheels (wheel- pinion), without outside teething, which are placed on the machine-tool (dividing head) tangent after the dividing circles (equal with the external diameters). In the tangent point we make a hole along the common generator of the dividing cylinders and implicit parallel to the wheels axis, as it is shown in fig. 1 and 2.

Further we manufacture similarly and succesively the other holes by division in order to achieve the pockets a, in which the cylindric and the tubular rollers will be mounted.