UA10358U - Novikovs transmission with two-line coupling with elliptic teeth - Google Patents

Abstract

Novikov’s transmission with two-line coupling comprises driving and driven toothed wheels with convex-concave circular teeth placed on those, being in interaction one with another in internal coupling. The side profiles of the convex-concave teeth are made by elliptic curves belonging to two ellipses; at that the ellipses have the same small semi-axis, though different in dimension large semi-axes.

Description

Description of the invention

The utility model refers to the field of mechanical engineering.

The Novikov OLZ gear transmission (one gear line) is known, which consists of the leading and driven gear wheels with convex and concave circular teeth located on them, which are in internal mesh with each other, and which, through interaction with each other, transmit the load and rotation frequency from one shaft to another shaft of machines and mechanisms (11: A.s. 109113 of the USSR. Gear transmission and cam mechanism! with point engagement system / M.L. Novikov (USSR); Published 04/19/56; Publ. 70 05/13. 57. Mo10 Blvd.

The disadvantage of Novikov OLZ transmission is a relatively low load capacity in terms of contact stresses; which is approximately 4095 higher than the load capacity of involute gears (21:

Pavlenko A.V., Fedyakin R.V., Chesnokov V.A. Gear transmission with Novikov gearing. - Kyiv: Technics, 1978. - 144p. 19 The closest in terms of technical essence to the proposed solution is the transfer taken as a prototype

Novikov DLZ (two lines of engagement), which consists of leading and driven gears with convex-concave circular teeth located on them, which are in internal mesh with each other, the load capacity of which in terms of contact stresses is higher than the load capacity of the transmission

Novikova OLZ in 1.7/1.4-1.214 times I2Y: Pavlenko A.V., Fedyakin R.V., Chesnokov V.A. Gear transmission with Novikov gearing. - Kyiv: Technics, 1978. - 144 p.; |From A. p. 735855 USSR. Gear transmission / R.V.

Fedyakin, V.A. Chesnokov (USSR); Proclaimed on 06/25/67; Publ. 25.05.80. Bul. Mob.

The disadvantage of the known transmission of Novikov DLZ is a slight increase in the load capacity in terms of contact stresses in comparison with the transmission of Novikov OLZ.

The task of the useful model is to increase the load carrying capacity of the transmission of Novikov DLZ by contact stresses. shsh

To solve the problem in Novikov DLZ transmission, which consists of driving and driven gears with convex-concave circular teeth located on them, which are in internal mesh with each other, the side profiles of convex-concave teeth are made by elliptic curves that belong to two ellipses, with In this case, ellipses have the same semi-minor axis a, but the semi-major axes are different in size. and c", and si"so. In addition, the minor semi-axis a is equal to the half-thickness of the tooth 5u/2, taken along the arc of the initial initial circle, in connection with which ah5u/2-l tu/4 and the major semi-axes of the ellipses are determined from the expressions gray dB kt, s - 05 kt, where ZU is the thickness of the tooth, which is taken along the arc of the initial circle; t , - the engagement module in the normal o 3o section; roi" roi" - the maximum radii of curvature of ellipses, i.e. convex and concave side profiles of the teeth, (7 which we find based on the parameters of the initial contours of the teeth, according to well-known dependencies.

A comparative analysis with the prototype shows that the claimed transmission of Novikov DLZ with elliptical teeth differs in that the side profiles of the convex-concave teeth are made by elliptical curves that belong to two "ellipses, while the ellipses have the same minor semi-axis and different larger semi-axis c- and c", and sikhso, in addition, had a semi-axis a which is equal to half the thickness of the tooth 5/2, which is taken along the arc of the initial circle, in connection with what ahZud/2-ya tu/4 a is larger the semi-axis of the ellipses can be found from the expressions;" si - 05 liters, Co - 0.5 liters, where ZU is the thickness of the tooth, which is taken along the arc of the initial circle; t , - the engagement module in the normal section; p 4, p » - maximum radii of curvature of ellipses, i.e. convex and concave side profiles of the teeth, which - are found, based on the parameters of the initial contours of the teeth, according to generally accepted dependencies. o Comparison of the declared technical solution not only with the prototype, but also with other technical solutions in this field of technology, did not reveal signs that distinguish the declared technical solution from the prototype, and this o allows us to draw a conclusion about the conformity of the "inventive level" criterion. 20 Fig. 1 shows the general view of Novikov's single-stage transmission; in Fig. 2 - the output circuit for cutting the teeth of the Novikov DLZ transmission (two lines of engagement); Fig. 3 is a graphical definition of the half-width of the contact section.

In accordance with Fig. 1-3 we have: od 4, yu 2 - Angular velocities of the driving and driven gears; rusya Ta - engagement step; 5,-M-ru/2 - respectively, the thickness of the tooth and the width of the cavity, taken along the initial straight line; yo -0.9tu, 59 peE1.05ty - the height of the head and the height of the foot of the tooth; tu - engagement module in a normal section; and 3-1.8tv depth of sunset; n-0.52209t, - the distance from the initial straight line to the point of contact on the side profile;

Is. -0.4011v t, I-0.48333t,, x0.13334 t, - coordinates of the centers of curvature r h, r 2; r 41» r 2 - maximum radii of curvature of ellipses, i.e. convex and concave teeth; C-0.15t - radial gap; |"Ktu) - side clearance; at. K-259-309 bo 7 Pressure angle; r 150.52155t, - the radius of rounding of the side profiles of the teeth.

The Novikov gear consists of a leading gear wheel 1 with convex-concave external elliptical teeth 2 located on it and a driven gear wheel 3 with convex-concave internal teeth 4 located on it. At the same time, these elliptical teeth are in internal mesh with each other. 65 Tooth 2 of the driving gear wheel 1 consists of a tooth head 5 with convex elliptical side profiles 6 and a leg 7 with concave elliptical side profiles 8 (Fig. 2). Similarly, the tooth 4 of the driven gear Z consists of a head 9U with convex elliptical side profiles 10 and a head 11 with concave elliptical side profiles 12.

Convex-concave elements of the side profiles of the outer 2 and inner 4 teeth represent sections of curves that belong to ellipses, in which the minor semi-axis a is common, and the major semi-axes are respectively equal to si so, de sixo.

Novikov's transmission works as follows. When the engine transmits the payload in the form of torque and rotation frequency to the drive gear 1, the latter will rotate with an angular speed of 4. At the same time, the external tooth 2, which belongs to the drive gear and is in 7/0 engagement with the internal tooth 4 of the driven gear wheel C, will act on this tooth in such a way that the driven gear wheel C will begin to rotate with an angular velocity, while receiving the payload.

In Novikov DLZ transmission, the head 5 of tooth 2 is in contact with the leg 11 of tooth 4, and the leg 7 of tooth 2 is in contact with the head of tooth 4. In this connection, there are two lines of engagement (DLZ), which during the time when the engaged pair of teeth are in engagement will move in the direction of length bu.

To evaluate the effectiveness of the proposed transmission of Novikov DLZ with elliptical teeth, we will solve the spatial contact problem based on the methodology of theoretical tests of the contact strength of various gear mechanisms with any tooth shape, developed by Dr. Prof. Popov O.P., the main provisions of which are sufficiently widely covered in open print.

On the basis of the performed solutions, the conclusions of which are not given, we will write down the expression for finding the half-width B 0 1 half-length B, the area of contact of the conjugated and tensioned pair of teeth of the proposed Novikov gear transmission: tu/4 - minor semi-axis of ellipses; A - dimensionless parameter, which is found according to the formula: ve ve. -

A - 1 1-- - A 1-- - 5 (3 rga and --- Poisson's ratio; E - modulus of elasticity of materials; Ka Sh/| 2(ts- 1)8vipo; ksozr zip"r) - reduced radius of from the curvature of the teeth in the plane, coinciding with the direction of the length of the teeth B, 4 - the diameter of the initial circle of the driving gear wheel; and - the transmission ratio; the sign "-" for the external, and the sign "-" for the internal SCHO arrangement of the gears; E04-5, Ru/2 - normal force acting on the most loaded tooth head of the driving gear wheel; P, - normal force acting on a coupled pair of teeth; 75, -1.05-1.15 - a coefficient that takes into account the overloading of the tooth head of the driving gear wheel in comparison with the head of the tooth driven by 5 gear wheel. "-

Equation (1) is obtained in an open form, according to which it is solved graphically. For this purpose, we denote the left side of equation (1) by ф (Bo). Then, with the given values of Bo; 0.5; 1.0; 1.5; 2, Ohm, etc. the function f (Bo) is constructed in the coordinate system f (Bo)-Bo. Next, on the ordinate axis sf (Bo) « we set aside the value of the dimensional parameter C-8(1-m ЗЕ/х "Е in mm? and through the indicated point of intersection of the straight line С with the ordinate axis, a horizontal line is drawn to the intersection with the curved line of the function «р (Bo). The point s of the intersection of line C with the curved line of the function f (Bo) represents in each specific case the desired "" value of the half-width of the contact section Bo (Fig. 3). we find the dimensionless parameter A for the given value of Bo according to formula (3), based on its value according to formula (2) we calculate the half-length of the contact area B. - Knowing the dimensions of the contact area B o and Bu, we find the expression of the maximum contact stresses in the proposed transmission Novikov DLZ 2 9) Sne - t) sta - Yam Ma (a x lovko pubic p where s tz-Рпи/4Бб0Б5К - values of average contact stresses. i42) Approximately to the traditional transmission of Novikov DLZ with circular teeth expression of maximum contact stresses with pz, half width B o and half the length of B, the contact areas will look like this (4)! Popov A.P., Popova

L.A. The refined solution of the contact problem applied to Novikov's engagement// Sat. of science works of UDMTU. -

Mykolaiv, 2002, Mo7(385). - P.61-71. 2861 s sy - ОВ uma Er, - allow, "vd - VO, where ey E (05-А ME ey o - vyt - coefficient; p Uriro(ro-ri) - reduced radius of curvature of the teeth in a plane perpendicular to the plane, 60 where is the reduced radius of curvature of teeth B.

On the basis of the given expressions, we will perform comparative calculations of transmission of Novikov DLZ with elliptical and circular teeth, based on DLZ - 1.147-0.16; tach ohm; 24-31; 0-2.03; o di1-164.99mm; B, -bOhm; Ep-5.21570N; ok-279; 5rfV 209; m-0.3; X 1; E-2.1710 MPa. dB According to the well-known and given formulas, we find p 4-I,147ty-5,735MMm; ro-(I,1470.16)t -6.535MM; p - 46.848mm; K-1004mm; at; kK-0.216; a-3.925 mm; C-0.09165mm2; with not 975 MPa.

Given the values: bo-0; 0.5; 1.0; 1.5; 2.0 mm, we will calculate the value of the function Ф (б0о)-0; 0.00072; 0.00262; 0.0641; 0.229mm2. Based on the data of F (Bo) and Bo, we will construct a curve (Fig. 3), which at C-0.09165 mm 2 gives the desired value

Bo-1.64mm. With Bo-1.64mm, we find the value of A-0.00746 according to formula (3), based on which, according to formula (2), we find B-7.821mm. In accordance with the values of br and B, from the expression (4) we obtain c-824MPa.

It is obvious from the comparison that the replacement of circular teeth with elliptical ones led to a decrease in the maximum contact stresses by 974/824-1.182 times, which is equivalent to an increase in the load capacity of the proposed Novikov DLZ transmission by 1.1823-1.651 times.

In addition, the maximum contact stresses in the involute gear with the specified dimensions and engagement angle of U-2092 are equal to (-1148MPa, and they are 1148/824-1.393 times higher than the similar stresses in the proposed Novikov DLZ transmission with elliptical teeth, which equivalent to an increase in its load-bearing capacity in terms of contact stresses by 1.393 3-2.703 times. At 7 -1.15, we determine c-o1054mm, Bo-1.72mm (Fig. 3), A-0.00859, B-8.21MmMm, s na-862MPa and with nE-1020MPa.

Thus, at А-1.15, the stresses from s with s nyu - did not increase much compared to similar stresses at 7, -1, but the ratio b dk/s ne-1020/862-1.183 remained almost unchanged.

If we assume the same load capacity of Novikov DLZ gears with elliptical and circular teeth, then in this case the service life of the proposed gear increases, based on the approximate dependence obtained on the basis of the Weller equation, by (s tsk/s no)l -4.82 times .

The economic effect of the implementation of the proposed technological solution should be expected at the expense of increasing the load capacity of Novikov gears, or at the expense of increasing the service life.

The public benefit of the proposed useful model is to improve the vibro-acoustic characteristics of transmissions due to the reduction of vibration and noise due to smoother operation of the engagement (industrial sanitation).

Claims (1)

The formula of the invention t Transmission of Novikov two-line gearing, which consists of leading and driven gears with convex-concave circular teeth located on them, which are in internal (ee) engagement with each other, which differs in that the side profiles of the convex-concave teeth are made according to elliptic curves, which belong to two ellipses, while the ellipses have the same minor semi-axis 4, but different major semi-axes c; and c, and sukhs-, in addition, the minor semi-axis a is equal to the semi-thickness of the tooth 5,/2, taken along the arc of the initial circle (9, in connection with ЧИМ a - 5u/2 - yam 4 , and the major semi-axes of the ellipses are determined from expressions o Si same 05 lita, bat Poly liva, | "- where ZU - the thickness of the tooth, which is taken along the arc of the initial circle; t , - the modulus of engagement in the normal section; 21, d" - the maximum radii of curvature of ellipses, i.e. convex and concave side profiles of the teeth, which are found based on the parameters of the initial contours of the teeth, according to well-known dependencies. "- with . and? - («c) (95) 1 IC e) c 60 b5