SU1716217A1 - Gearing - Google Patents

Abstract

This invention relates to mechanical engineering, to shiftable helical gears. The purpose of the invention is to increase the reliability of transmission with helical gears, which is achieved by using additional support elements for movable wheels, which reduce play and increase the rigidity of the gears. The axle-moving crown of the gear-toothed wheel in engagement with the counter wheel 5 is supported on the conical disk 11. The geometrical parameters of the disk 11 are selected from the so-called i fift bearing: 2 (arctg-j- --Ј) уЈ2 х х (arct9 --t - |), (d-6.5m) dk (d-Btgy),

Description

The invention relates to mechanical engineering and can be used in boxes of speeds and feeds of machine tools having a step change in the speeds of rotation of the shafts.

Known multi-stage gear .. transmission speeds and feeds machines with interchangeable wheels.

The disadvantages of the known constructions are their relatively long-term reconfiguration, as well as high vibroactivity, low load capacity and reliability.

The gearing is the closest to the proposed one, containing shafts, meshing spur gears mounted on them, at least one of which is made in the form of a conical thrust disk fixed to the shaft and mounted with the possibility of axial displacement supported on it. tapered surface on the crown disk.

The disadvantage of the design is low reliability.

The purpose of the invention is to increase reliability.

The goal is achieved by the fact that in a gear transmission containing shafts, mounted on them engaging spur gears, at least one of which is made in the form of a conical thrust disk fixed to the shaft and mounted with the possibility of axial movement of the corresponding internal conical surface on the crown disk, in gears with helical gears, the angle of taper of the corresponding contacting surfaces of the disk and the crown and the diameter of the larger base of the patterns These cones are selected in these ranges.

2 (arctgI r- |)

(x (arctg-t 7Ј

+ Ј), (d -6i5m) dk

()

where is the angle of engagement; / - angle of inclination of the teeth; | - self-locking angle; d is the diameter of the pitch circle; m - module

teeth; B is the width of the ring gear (the distance from the end with the annular conical groove to the protruding end of the ring gear), with the directions of inclination of the teeth on the sliding gears.

Block 0 are made opposite to each other and are selected from the condition of pinching the gear to the corresponding clamping element during the transfer of the load.

To reduce the switching force

5 gears due to reduction of friction forces in conjugation of the conical surfaces of the clamping elements and gears on one of the interacting conical surfaces of the pair of the clamping element 0 gear were made to reduce the contact area of the said surfaces.

FIG. Figure 1 shows a gear; in fig. 2 - block interaction diagram

5 gears with clamping element; in fig. 3 - the choice of the direction of inclination of the teeth depending on the direction of rotation (the driving element is the gear 2 of the block 1).

0 Toothed gear contains a sliding gear unit 1 with two toothed rims 2 and 3, fixed in the axial direction of the gear unit 4 with the crowns 5 and 6, the toothed wheel 7 permanently engaged with the crown 6, mounted on shafts 8, 9 and 10 rotatably.

On the shaft 8 with a sliding block of gears 1 are mounted the clamping elements 11,12 to limit the radial and axial

0 movements of the sliding gear unit 1 after engaging gears 2 or 3 in engagement at full working width with rims 5,6. The rims 2, 3, 5, 6 and 7 are made with oblique teeth. At the same time, on the crowns 2 and 3, the directions of inclination of the teeth (depending on the direction of rotation of the shaft 8) are chosen so that when the load is transferred in pairs 2-5 or 3-6, the crowns 2 or 3 are pressed to the clamping elements 11, 5 12 under the action of forces R (the resultant axial Dew and radial Rrad components of the load) (Fig. 2 and 3).

The base elements 11, 12 are made in the form of truncated cones facing 10 smaller bases to the end surfaces of the gears 2. and 3 of the sliding block 1. On the end surfaces of the sliding block of gears 1 facing the base elements 11,12, the response based elements 11 and 12 grooves.

The angle of taper of the base elements 11, 12. is selected from the condition of the resultant axial and radial forces R normal to the base surface 13 15 or 14.

 P tgg 97 Ppug P-tgawcos where P is a circumferential force;

/ 5 is the angle of inclination of the teeth;

 hooking angle.

Then have arctg Ј with this in a03

There is a deviation from the normal to the clamping surface within the self-locking angle. nor to prevent the sliding block of gears 1 from tilting under the action of the component of the resultant force R., which appears in this case, directed along the conical surface.

With this in mind.

20

thirty

2 (arct9 -®-Y-2 (arclgWEf

The diameter of the larger base of the truncated cone formed by the conical surface 15 or 16 at the end of the gear ring 2 or 3 die is chosen from the condition

dK d - (6,5. m - V. tgy)

as if - in. tgjVo the resultant force goes beyond the dimensions of the supporting conical surface 13, 14 on the clamping element 11 or 12, which leads to tilting of the sliding block 1 on the shaft 8.

With dK d - 6.5 m - the thickness of the rim from the end with the conical groove becomes less than two modules, which leads to the breakage of the teeth.

To reduce the effort to turn off gears by reducing frictional forces in the mating of the conical surfaces 13-.16 of the clamping elements 11, 12 and gear wheels 2, 3, slots (not shown in Fig. 1,2,3) can be made, reducing the contact area mentioned conical surfaces.

five

ten

15

.

20

thirty

25

3Q

"with

40

When the gear is working, the crown 2 or crown 3 is engaged with the crown 5 or crown 6, respectively. After the crown 2 teeth or crown 3 teeth are fully engaged, the sliding block of the sheshegene 1 is supported by a conical bearing surface 15 or 16 on the conical bearing surface 13 or 14 11 or 12 based elements.

When power is transmitted, the forces acting in the helical engagement of the rims 2-5 or rims 2-6 act on the gear rim 2 or 3 in such a way that the sliding block of gears 1 presses against the clamping elements 11 or 12, which eliminates the the operation and eliminate the radial and circumferential movements of the block 1 relative to the shaft 8. As a result, due to a decrease in the dynamic component of the load and an increase in the overlap ratio, the load capacity increases and v decreases the vibro-acoustic activity edachi and thus increased reliability.

The transmission is simple in design, technological, and has high technical and economic indicators.

Claims (2)

1. A gear transmission containing shafts, mounted on them, engaging spur gears, at least one of which is made in the form of a conical thrust disk fixed to the shaft and mounted with the possibility of axial movement supported by a corresponding internal conical surface formed on it on a crown disk, different in that, in order to increase the reliability of transmission with helical gears, the taper angle of the respective contacting surfaces of the disk and the crown and the diameter of the larger base and formed by these taper surfaces are selected in the ranges 2 (arag | M) 2 (arc, g || Ue (d-6,5m) dk (d-B-tgy), where y is the taper angle of the contacting surfaces of the disk and the crown; / - angle of inclination of the teeth of the wheels; QW-engagement angle; Ј is the angle of self-braking; dK is the diameter of the larger base of the cone formed by the contacting surfaces of the disk and the crown; d is the diameter of the pitch circle; m is the crown teeth module; In - the width of the crown. 2. Transmission according to claim 1, characterized in that the surfaces of the disk and the crown are made in one of the contacting parts. eleven fig.Z