The product development process of products manufactured in transport equipment production enterprises is a very complex process and it influences the product life cycle of said equipment. The goal of the paper is to identify this process in the area of product design as a part of the whole development process, taking into consideration its particular stages and phases. The product development process was formulated as a general model and then presented on the design example of a handcar machine, taking into consideration the characteristic input and output data. This example concerns real conditions in a manufacturing enterprise.