1、中文 3700 字 Variable Arc Gear Principle and the Formation of Abstract To a class of variable arc gear. Use of deviation function, given the tooth profile of the structural integrity of the process, proved its tooth profile engagement to meet the basic law of tooth profile equation derived basic formul
2、a, discussed the changing arc of the gear, given the changing arc tooth Profile examples； such gear has a high carrying capacity, especially for high-speed, high-precision CNC machining, it will be occasions in the heavy transmission applications. Keywords： gear, profile, deviation function, engagem
3、ent principle, gear strength Introduction With the development of science and technology, to drive the requirements have been increased, particularly in the area of heavy and small is particularly prominent. At present, the gear used in the design of a involutes line, and cycloid arc tooth profile t
4、hree of them, involutes gear due to manufacturing simple deviation from the Centre not sensitive to the advantages of widely used, but it bearer Less and less for heavy transmission； cyclonical gear contact stress small, tooth profile of the coincidence of large and is conducive to the improvement o
5、f bending strength, but the meshing of gears precision manufacturing and assembly higher； last century 1950s the arc gear bending strength is not high, in order to achieve continuous contact to be made generally helical gears, and small manufacturers in the area have been greatly restricted. In orde
6、r to increase the carrying capacity of gears, the researchers put forward a number of new tooth profile, for example: micro-segment gear profile, dual-band involutes gear, the gear increase the intensity could play a role, but these new teeth Profile in the manufacturing or assembly areas there are
7、still certain deficiencies. This deviation from the concept of function, a new type of gear - gear change arc. The paper introduced the arc gear change the formation of principle, derived Tooth formula, discussed the changing arc of the gear is given tooth profile examples. 1 A variable arc tooth pr
8、ofile of a principle 1.1 Variable arc tooth profile of a principle Below D. C. H. Yang according to American scholars, such as the deviation function (DF), variable arc tooth profile on the formation of principle. P1 is a radius of a circle of the gear section, 1 for the corner to e(1) radius, evenl
9、y distributed in the center of a round, painted a series of round, as shown in Figure 1 (here for e(11) = 0r COS(21)； When e(1) bound to meet certain conditions, this series of round envelope can to smooth the tooth profile g1 (1), can be seen from the map, e1 (1) = | | P (1) - g (1)| |, said e (1)
10、for the deviation function and we will meet the above principle of formation of a tooth profile collectively referred to as variable envelope arc tooth profile, referred to as variable arc tooth profile, It constitutes a change of gear known as the Arc gear. When the deviation from function e（ 1） =
11、r1cos（ ） , the change is the common arc tooth profile of the involutes tooth profile, and when the deviation function for )2s in (2)( 10101 rrre Then changed the arc tooth profile Cycloid is the tooth profile, and the general arc gear, the equivalent of deviation function e(1) only in certain discre
12、te points value. 1.2 arc tooth profile change the calculation Can be seen from Figure 2, the component that coordinates with the gear change arc tooth profile of the equation for P1 )c o s ()c o s ( 1111 erg x (1) )s i n ()s i n (1111 erg y (2) - In, defined as the point g tooth profile of the norma
13、l line with the angle between the x-axis, which is a function of 1 from Figure 2 that 1 ee 11 rL )(ta n 2211ereb a c bacoaooao 11111 )( )2/0( 1 （ 3） In order to get the tooth profile to the practical application, the deviation must also function e(1) the choice to do certain restrictions (1) To ensu
14、re the tooth profile of non-crossing to |)cos(| 11 re （ 4） (2) To ensure that equation (3) Solution for 212 re （ 5） (3) To ensure the contour of C continuous, in the section with a round p1 Tooth g1 at the intersection of Cp, e(cp) must be zero. (4) To ensure Tooth fairing, in e(1) minimum, between the maximum change must be monotonous. (5) In order to gear teeth N1 for integer and ensuring that a certain overlap factor , the meeting point between the point of view of the 1 should meet. 11 n
