In this paper a method for the modified profile of a rack cutter is presented. The deviation function method is used to reshape a rack cutter. The author proposes a modified geometry of a rack cutter to generate the driving gear of internal gear pairs. Based on the double envelope concept, the driven gear of a set of internal gear pairs can be determined. In this study, the Von-Mises stress analysis of the reshaped internal gear pairs was carried out and the specific phenomena was also investigated. The results show that it is possible to compensate elastic deformation and reduce contact stress between conjugate gear pairs. In addition, according to the tooth contact analysis on the gear pairs, reshaped gears and conventional gears have also been investigated. Computerized design of internal gears using the proposed method and simulation of their meshing and contact stress analysis of asymmetric internal gears has been developed. The developed method is illustrated with numerical examples.