SU1229484A1 - Friction planetary gearing - Google Patents

Description

one

The invention relates to planetary friccian transmissions and can be used in mechanical engineering in mechanisms and devices for various purposes where automatic control of the magnitude of retransmitted torque is needed.

The purpose of the invention is to automatically control the amount of transmitted torque, increase reliability and durability,

FIG. shows the proposed transfer section; figure 2 - scan of the imaginary cylinder, the shape of which passes through the centers of the balls; on fig.Z - multistage transmission, section.

The friction planetary gear train comprises a housing 1, a high-speed 2 and a low-speed 3 shafts, central wheels 4 and 5 with grooves 6 on the outer and inner working surfaces, mounted respectively rigidly on the high-speed shaft 2 — wheel 4 and stationary in the housing 1 — wheel 5, connected with a low-speed shaft 3 the carrier 7 with sockets 8 at its end, made in the form of grooves, the profile of which in the radial direction is a trapezoid facing a large base to the end of the carrier, the satellites placed in the sockets 8 of the carrier 7, made in vzayuyudeystvuyuschye balls 9 and the groove 6 of central wheels 4 and 5.

The friction planetary gear operates in the following manner.

Rotation from the high-speed shaft 2 is transmitted to the wheel 4 with external gearing, which transmits the rotation to the satellite balls 9. The latter, rolling in the grooves 6 on the inner surface of the fixed wheel 5, report rotational motion

94842

 drove 7, as well as connected with him low-speed shaft 3.

Here, the gear ratio is defined as for normal

friction planetary gears and depends on the ratio of the working diameters of the central wheels 4 and 5 and the satellites.

In addition, the implementation of the nests of the driver 7 in the form of the grooves 8 contributes to the pressing of the balls 9 to the lateral sides of the grooves 6 of the wheels 4 and 5, and, consequently, reduces their slippage relative to the latter.

5 rotation shaft 2 and 3 can be any. When the gear is operating in multiplier mode, the rotation is transmitted from the low-speed shaft 3 to the high-speed shaft.

0 In the case of an increase in the moment of resistance on the low-speed shaft of the ball 9, under the action of the torque, the wheels 2 tend to move along the inclined surface of the conical grooves.

5 8 drove 7, due to which the pressure of the balls 9 to the side surfaces of the grooves 6 of the wheels 4 and 5 is increased. The transmitted torque in this case increases and corresponds to

30 gear ratios of the transfer to the moment of resistance on the low-speed shaft 3. In the opposite case, the force of pressing the balls, taking into account the effect of the reaction force of the lateral sides of the grooves 6 of the wheels

and 4 and 5, which exceeds the seizure force of the balls 9, will decrease and the latter will take a position corresponding to a torque.

The magnitude of the angle o (the angle between the side groove of the carrier and the plane of rotation of the balls) is selected for each transmission size, taking into account its characteristics and operating conditions. Transmission can be performed multistage (fig.Z).

Fig 2.

ig.Z

Claims (1)

FRICTIONAL PLANETARY TRANSMISSION, comprising a housing, high-speed and low-speed shafts located therein, central wheels with grooves on the outer and inner working gear 1 of the surfaces rigidly mounted respectively on a high-speed shaft and in the housing, connected to a low-speed shaft, drove with sockets at its end and placed in the last satellites made in the form of balls interacting with grooves of the central wheels, characterized in that, for the purpose automatic adjustment of the transmitted torque, increasing reliability and durability, the nests are made in the form of grooves, the profile of which in the radial direction is a trapezoid, facing g with a large base to rtsu carrier. SU 12294