SU1240991A1 - Adjustable pulley - Google Patents

Description

The invention relates to mechanical engineering and can be used in continuously variable belt drives for smooth adjustment of the rotation speed of an actuator.

The purpose of the invention is to increase the adjustment range and simplify the change of the working diameter during operation due to a more uniform gear ratio and the possibility of automatic control of the pulley during operation. ,; FIG. 1 depicts an adjustable: pulley, axial section; in fig. 2 shows section A-A in FIG. one; in fig. 3 shows a section in FIG. one; . 4 is a view of B in FIG. 3

The pulley consists of a hub 1 rigidly mounted on the drive shaft 2, a pressure disk 3, on the front part of which a spiral groove is made, and on the cylindrical part of the screw is a groove b, and the pressure wheel 3 is mounted on the hub 1 for rotation.

On the hub 1 by means of consoles 4 a guide 5 disk is fixed, along T-shaped radial guides of which the leading 6 sectors can move in the radial direction, on the outer cylindrical surfaces of which there are grooves r for holding the belts. At the ends of the leading 6 sectors are made with a radius equal to the radius of curvature of the helix, spikes e, which engage with the helical and groove. On the cylindrical part of the pressure disk 3, a second pressure disk 7 is installed, in the central hole of which a thread is cut, allowing the disk 7 to mate with the screw b groove of the pressure disk 3. On the second pressure disk 7, there are T-shaped radial guides e, in which slave 8 sectors are placed with the ability to move along the T-shaped guides B in the radial direction. The pressure disc 7 and the guide disc 5 are mounted in such a way that the slave 8 sectors are located between the leading 6 sectors. Leading 6 and driven 8 sectors are made in the form of truncated pyramids directed towards each other by their truncated vertices. The side surfaces with which the supporting sectors 6 and 8 are mated have straight ridges and depressions to increase the rigidity of the pulley. The outwardly facing surfaces of the slave 8 sectors are made convex, and the radius of curvature of these surfaces increases as the base of the truncated tetrahedral pyramid approaches the base (Figs. 3 and 4).

With the smallest working diameter, the leading 6 and driven 8 sectors are mated so that the outer surfaces of the driven 8 sectors are located between the notches and leading 6 sectors, and

 undercut g is formed by a single working surface without gaps, on which a flat or wedge (depending on the shape of undercut g) is put on a belt (not shown). The gearbox 9 can be rigidly connected to the end of the hub 1, the axis of the output shaft of which can be displaced relative to the common axis of the pinch. A gear wheel 10 is mounted on the output shaft of the gearbox 9, which engages with a gear ring 3, which is made according to the internal diameter of the step 3 of the pressure disc. The input shaft of the gearbox 9 can be connected to the shaft of the electric motor 11.

Adjustable Shchivk works as follows.

If it is necessary to change the working diameter, a current is supplied to the electric motor 11. The wheel 10 rotates the pressure disc 3 through a gear ring. The leading 6 sectors move radially along the T-shaped guides from the interaction with the moving spiral and groove of the pressure 3 disc. Thanks to straight ridges and valleys, the leading 6 sectors carry the driven 8 sectors in the radial direction. Simultaneously with the movement in the radial direction, the slave 8 sectors move in the axial and together with the second pressure 7 disk move along the helical groove. The magnitudes of the steps of the screw and spiral and grooves are related to each other in such a way that the axial movement of the slave 8 sectors allows the choice of a wedge gap arising from the radial movement of the leading 6 sectors. Thus, between the undercuts of the leading 6 sectors, the convex surfaces of the driven 8 sectors appear, the radius of curvature of which is equal to the curvature radius of the grooves at a given time, and together with them form a continuous working surface of the pulley that is close to cylindrical.

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FIG. 2

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Compiled by O. Klimov

Editor N. Slobod nikTechred I. VeresKorrektor E. Roshko

Order 3472/32 Circulation 880 Subscription

VNIIPI USSR State Committee

for inventions and discoveries

113035, Moscow, Zh-35, Raushsk nab. 4/5

Branch PPP "Patent, Uzhgorod, st. Project, 4

FIG 4

Claims (4)

1. ADJUSTABLE PULLEY containing a hub, two pressure plates mounted on it, the first of which has a spiral groove, and the second has radial guides, a guiding disk with radial guides, the leading sectors connected between them with the possibility of radial movement, connected with them the help of the spikes located in the spiral groove and the radial guides of the guide disc, characterized in that, in order to increase the range of regulation and simplify changes in the working diameter during work , the first pressure disk is kinematically connected with the second screw-nut transmission and has a hub with teeth made on its inner surface, and the pulley is equipped with driven sectors located between the leading sectors and connected with the last and second pressure disk with protrusions and depressions made on lateral surfaces of sectors and spikes installed in the radial guides of the second pressure plate. 2. Pulley in π. 1, characterized in that the leading and driven sectors are in the form of truncated pyramids. 3. Pulley 1 and 2, characterized in that the working surface of the driven sectors has a variable radius of curvature increasing to their base. 4. Pulley in π. 1, characterized in that the surface of the spikes mating with the spiral groove of the pressure disk are described by a radius equal to the radius of curvature of the spiral. 11 7 3} J ^{ju 50} 3 12 d SU,. „1240991 Fig. /