| 摘要 |
FIELD: machine building.SUBSTANCE: distinctive feature of the proposed group of inventions is that the control value of the torque being less than the specified torque value, is specified in advance, and a ring-shaped thread gage (11) able of being screwed together with a spark plug (3) is used to control the position of the spark plug. The gage (11) is fitted by reference lines (14a, 14b) which show the upper and the lower end positions of ground electrode (33) orientation tolerance when the plug (3) and the gage (11) are screwed together. When the plug (3) and the gage (11) are screwed together and tightened by the control torque value, suitability of phase position in the rotation direction is evaluated and controlled by assessing, if the ground electrode (33) of the plug (3) falls within the range of reference lines (14a, 14b) showing the upper and the lower tolerance end positions.EFFECT: possibility of phase control with regard to the characteristics of seal crushing deformation by torque being less than the specified tightening torque.13 cl, 13 dwg |
