SU1656372A2 - Device for testing gears on bending strengthand tooth endurance - Google Patents

Abstract

The invention relates to mechanical engineering, in particular to testing equipment. The aim of the invention is to increase productivity when testing gears with a number of teeth that are a multiple of three, by simultaneously creating identical loads on three pairs of working surfaces of the teeth. During operation, the force of the loader 2 transfers the test wheel 6 to the teeth 4, 5 through the main roller 3, and then to the teeth 10, 11 and 12, 13, additional rollers 14 and 15, to the edge 8 and 9 of the prism 7 and the body 1. Since the rollers 3,14,15 are identical and located through 120 ° circumferentially, and the faces 8 and 9 of the prism 7 are made at an angle of 30 ° to the axis of the load 2, then the forces from the rollers 3. 14, 15 are the same. 1 il.

Description

The invention relates to mechanical engineering, in particular to testing equipment, can be used in tests for flexural strength and endurance of cylindrical gear teeth of wheels, the number of which is a multiple of three, and is an improvement of the invention according to the authors. St. No. 630545.

The purpose of the invention is to increase productivity when testing gears with a number of teeth that are a multiple of three by simultaneously creating an identical load on three pairs of working surfaces of the teeth.

The drawing shows a diagram of the device with the test wheel installed.

The device comprises a housing 1, a loader 2 disposed therein and a main roller 3 intended to be mounted in the cavity between the teeth 4, 5 of the cylindrical gear wheel 6 under test, the number

whose teeth are a multiple of three. The housing 1 also contains a prism 7, faces 8 facing each other, 9 of which are made at an angle of 30 ° to the axis of the load carrier 2 and mirrored to the last. Intended for installation in the other two cavities between teeth 10, 11 and 12. 13 wheels 6, respectively, additional rollers 14 and 15 are arranged to move prisms 7 on the facets 8 and 9 and in the same plane with roller 3. Distances between rollers 3 , 14,15 are equal, i.e. angles between them are 120 °. On the prism 7, a stand 16 is installed, having a surface concave in the shape of the test wheel 6.

The device works as follows.

For testing, the gear wheel 6 with the number of teeth, a multiple of three, is mounted on the prism 7, is placed between the teeth 4, 5 roller 3, which is pressed

(S

WITH

oh oh

Ca

V

TO

 TO

to wheel 6 by the loader 2. The assembled device is mounted on a testing machine (not shown). The force of the testing machine with a certain frequency in the form of a load P is transmitted through the roller 3 through pairs of teeth 10, 11 and 12, 13 to the rollers 14, 15 and further through the prism 7 to the device body 1. Since the rollers 3.14, 15 have the same design and dimensions and are located 120 ° around the circumference, and the angle between the inclined faces 8, 9 Prisms is 60 °, the magnitude of the forces acting on different pairs of rollers 3.14 and 15 are the same, t. e. P2 Pz Pi, since their vectors Form an equilateral triangle of forces, and therefore all three pairs of teeth 4, 5; 10, 11 and 12, 13, which are in contact with different rollers 3, 14, 15, operate under strictly the same loading conditions.

The action of the cyclic load from the pulsator on the 4,5,10,11,12,13 teeth in their Hazardous sections produces fatigue cracks, resulting in the failure of any of the teeth, for example, a pair of teeth 4, 5, according to the number of cycles which, prior to destruction, judges the minimum endurance limit of the teeth.

In order to obtain the law of failure distribution after a tooth breakage, 4 or 5 break the teeth 10.11 and 12.13 in the remaining two working pairs. For this, the wheel b is placed on the stand 16 and one of the pairs of unbroken teeth, for example, a pair of teeth 10, 11, is inserted in the contact with roller 3. Continue the test with the same load until one of the teeth of this pair breaks and then the same the way they break the teeth 12,13 of the remaining pair,

In this way, data are obtained which make it possible to establish the law of the distribution of failures (breakages) of the teeth.

In order to accumulate statistical data, tests are continued in a similar way — the remaining teeth of wheel 6 until 50% of its teeth are broken.

Similarly, tests for flexural strength are carried out, but instead of a pulsating load, roller 3 is applied with a gradually increasing load Pi, the value of which at the time of destruction (floor-i) is judged on the static (or dynamic, if the impact load) strength of the teeth.

When used in tests with identical sizes, rollers of various shapes (for example, roller 3 is made hollow, roller 8 is conical, roller 9 is barrel-shaped), you can immediately determine in one test which mold results in the most

fast tooth breakage, i.e. is the least favorable, which also improves the performance of the test for both flexural strength and endurance.

Taking into account that tooth endurance tests are long and expensive, the invention reduces test time and reduces their cost by increasing productivity by 3 times.

Claims (1)

Invention Formula Device for testing gears for bending strength and endurance of their teeth auth.St. N 630545, characterized in that, in order to increase productivity when testing gears with a number of teeth that are a multiple of three, it is provided with a prism placed in the housing, the faces facing each other of which are made at an angle of 30 ° to the loading axis and mirrored relative to the latter, and two additional rollers, each of which is mounted for movement on one of the faces of the prism and is designed to be placed in the cavity of the test wheels in the same plane as the main roller, and the distances between the centers of the rollers are equal.