SU1180591A1 - Worm gearing - Google Patents

Abstract

WARMERMAN TRANSFER, containing a worm mounted on the shaft, interacts with it a worm {L ///// VA /// A / L / L // // L ////// // Fg / g. a wheel and a safety device made in the form of a coupling disposed on a worm shaft and a spring cooperating with a coupling, characterized in that, in order to provide a two-sided torque limitation, the worm has a shank on which surface is threaded The direction of which is opposite to the direction of cutting of the screw, and the coupling is mounted on the shaft on the splines with the possibility of interaction with the thread of the shank. (L / 4 00 About SP

Description

1 11

The invention relates to mechanical engineering and can be used in electric valves.

The purpose of the invention is to provide two-sided torque limiting. -

Fig. 1 shows the worm gear, general view; FIGS. 2 and 3 are the same when loading a starting torque with a given torque and driving the input shaft clockwise or counterclockwise.

Worm gear The transmission contains a worm 1 mounted on the input shaft. 2, interacting with the last worm gear 3, the output shaft 4, a safety device made in the form of a clutch 5 placed on the shaft 1, a worm 2 and a spring 6 interacting with the clutch. A screw to, 1 has a shank 7, on the surface of which a thread is made. Coupling 5 is connected to the inlet J: OM by the splines 8, and with the worm stem by a thread 9, the thread direction of which is opposite to the cutting direction on the screw mounted on the output shaft on the keys 10. Coupling 5 and ring 11 interacting with engine switch 12 , clamped to the screw with a spring 6, resting on the ring 13,

Worm chna transmission works as follows.

The rotation from the electric motor is connected to the shaft 1, as well as through the splines 8 to the coupling 5, which, being screwed on the screw to 2 up to the stop and pressed by the spring 6, tells the screw 2 to rotate. When a load is applied to the shaft 1, the ring 3 stops, and the screw to 2, continuing to rotate, tends to move along the shaft to the left, depending on the direction of rotation of the electric motor.

912

When the shaft 4 rotates in one direction, the screw 2 moves to the left together with the ring 11, which, acting on the switch 12, turns off the engine when a given load is applied to the shaft 1 (Fig. 2). If the shaft 4 rotates in the opposite direction (Fig. 3), then the worm to 2, rotated by the clutch 5 iaa account

friction in the thread, it is not possible to shift right, o, against the bearing 14. In this case, when a given load is applied to the shaft 2, the worm k stops together with the wheel, and the coupling 5 is screwed - with the worm, because the cutting direction the threads are opposite to the direction of cutting the screw, and the ring 11 switches off the electric motor.

 The drive is tuned to a specific torque by setting switch 12 to the distance N. Herewith, the magnitude of the limiting moments during the rotation of the engine

, in one and the other side are related by

M. I} i (.)

. (o./,h2%j

where M is the moment at the offset of the screw;

And ,, - the moment at the displacement of the coupling; B - diameter of the initial circle

worm,

 - the angle of elevation of the coil turn; p - friction angle in the heart

gearing;

c (is the average diameter of the thread; 0 is the angle of elevation of the thread; f-i is the angle of friction in the thread,

p is the rolling friction angle in the bearing.

In the proposed worm gear design, a two-sided torque limitation is performed using a single spring.

Claims (1)

WORM TRANSMISSION, comprising a worm mounted on the shaft, a worm wheel interacting with it, and a safety device made in the form of a clutch located on the worm shaft and a spring acting on the clutch, characterized in that, in order to provide two-way torque limitation , the worm has a shank, on the surface of which a thread is made, the direction of which is opposite to the direction of cutting the worm, and the coupling is mounted on the shaft on the splines with the possibility of interaction with the thread of the shank. SU ,,. 1180591