Answer Happy

Calculation of worm-gear For worms and wheels of cylindrical worm-gears module of m, mm, normalized on a row, : 1,0; 1,25; 1,6; 2,0; 2,5; 3,15; 4,0; 5,0; 6,3; 8,0; 10,0; 12,5; 16,0; 20,0; 25,0. Transmission relation of transmission i = ²2, (15.1) where zl, z2 is a number of coils (measures) of worm and teeth of wheel, accordingly. The number of coils of worm is accepted depending on a transmission relation by transmissions: -Z₁ = 1 at i>35,5; -Z₁ = 2, 3 at 18<i<35,5; -Z₁ = 4 at i≤18. For worm-gears the basic values of gear-ratios of i are standardized TOCT2185 - 66. The basic values of gear-ratios of i for worm reducing gears following: 1-and row 1,00; 1,25; 1,60; 2,00; 2,50; 3,15; 4,0; 5,0; 6,3; 8,0; 10,0;12,5; 16; 20... 2-and row 1,12; 1,40; 1,80; 2,24; 2,80; 3,55; 4,5; 5,6; 7,1; 9,0; 11,2; 14; 18; 22,4... At the choice of standard parameters the first row is more acceptable of the second, and the purchased values of gear-ratios for worm-gears must not differ from a calculation no more than on 4%. For cylindrical worm-gears with the corner of crossing of axes of worm and wheel, even 90 for FOCT 2144 - 76 normalized: dividing corners of getting up of coils of worm, length of worm and interaxle distances : 1-and row aw 40; 50; 63; 80; 100; 125; 160; 200; 250; 315; 400; 500. 2-and row aw ----- 140; 180; 225; 280; 355; 450. Worm-wheel determined size on the same calculation dependences as for gear-wheels. For standardization of standard instrument, used at cutting of worms and worm-wheels, relation of dividing diameter da 1 worm to the calculation module of T, called the coefficient of diameter of worm of q, normalize for IOCT 19672- 74 within the limits of q = d₁6,3...25.. It is recommended to accept to m accept q = 0,25z2,, thus q ≥ 0,21z2. It is set a standard two rows of values of coefficients of diameter of worm of 9: 1-and row 6,3; 8; 10; 12,5; 16; 20; 25; 2-and row 7,5; 9; 11,2; 14; 18; 22,4. In small-modular transmissions the coefficient of diameter of worm of q it is recommended to take anymore, as worms in them can appear hard not enough. Tangent of dividing corner of getting up of coils of worm and angle of slope of teeth of wheel
tgy = 21. (15.2) The values of dividing corner of getting up of coils of worm depending on his parameters are driven to the table 1. Table 1 Dividing corner of getting up of coils of worm ZI 1 2 3 4 14 12 10 9 8 7,5 16 3°34′35" 4°05'09" 4°45'49" |5°42′38" 6°20′25" 7°07′30" 7°35'41" 7°07′30" |8°07′48" 9°27'44" 11°18′36" 12°31'44" 14°02′10" 14°55'53" 10°37'15" 12°05'40" 14°02′10" 16°41'56"|18°26'06"20°33′22″21°48'00" |14°02′10″|15°56′43"|18°25′06″21°48′05″23°57′45″|26°33′54″28°04′21" The basic geometrical parameters of worm-gear without displacement are shown on rice. 1 determined on dependences: - dividing and initial diameters of worm and wheels: d₁=dw₁ = q m, (15.3) d₂ = dw2 = Z2 m; (15.4) - diameters of tops of worm and wheel: da = d₁ + 2h m = m (q + 2), (15.5) da2 = d₂ + 2ha. m = m (z₂ + 2); (15.6) - diameters of hollows of worm and wheel: df₁=d₁-2h; m = m (q-2,4), (15.7) df2= d₂ - 2h; m = m. 2 (22-2,4). (15.8) det de de d₂ de Rice. 1. Geometrical parameters of worm-gear In a worm-gear without displacement height of teeth and coils: h=h₂ + hy = (2h +c") · m = 2,2m. (15.9) .
For a transmission without displacement dividing interaxle distance but also interaxle distance of aw : a = a = 0,5 . (d₁, +d₂) = 0,5 m (q + z₂), (15.10) The module of a worm hooking is checked up for dependences m= (15.11) Q+zz The most diameter of worm-wheel is determined on a formula 6m dam2 ≤ daz + . (15.12) Conditional corner of circumference 28 worms of crown of gear-wheel are determined from a condition: sin(8) = b₂ (15.13) da-0,5m Length of the cut part of worm accept: at z1=1 and 2-b₁ ≥ (11 +0,06z₂).m; at z1=3 and 4-b₁ ≥ (12,5 + 0,09z2). m. Width of crown of gear-wheel: At Z₁ = 1,2,3-b₂ ≤ 0,75d₂= 0,75.Z₂.m At Z₁ = 4-b₂ ≤ 0,67d₂ = 0,67 22. m. Other sizes of gear-wheel are accepted by such as for gear-wheels. Displacement of cylindrical worm-gear with an archimedean worm is carried out only due to a wheel, the sizes of worm, except for the diameter of initial cylinder, do not change. Maximum value of coefficient of displacement in default of paring and intensifying of teeth of worm-wheel it is recommended to accept x<+1. Negative displacement it follows to avoid from a decline to durability of teeth on a bend. The minimum number of teeth of wheel in a power worm-gear is accepted =26...28. At a choice and depending on a gear-ratio and it is necessary to bear in a mind, that for a transmission without displacement in order to avoid paring of teeth of wheel it must be z2 > 28. Task: to expect the parameters of worm-gear, initial data on variants (table. 1). Ne to the variant 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 Z₁ 1 2 4 1 3 2 1 4 4 1 2 1 4 1 2 Z₂ 28 30 32 26 29 35 40 36 38 42 26 S 30 38 36 40 Table 1 If the calculated parameters do not match the values of the series, change the source data Z₂.