Abstract: Based on the study of thinking mode, the legitimacy thinking mode is put forward in teaching of mechanical drawing course. Through comparison with current thinking mode, the problem of too emphasizing the image thinking and too neglecting the logical thinking is found out. Taking the reading method of combination solids as example, the programmable innovation design for this content are designed to strengthen the logical thinking. The teaching practice shows that the former state “can understand but can not be used” is changed and this new teaching method is welcomed by the students.

Key words: engineering graphics, programmable innovation design, logical thinking, combination solids