PURPOSE: To enable the adjustment of a spring constant to a prescribed value inexpensively, by changing the shape of a leaf spring whose spring constant is made higher than the prescribed value.
CONSTITUTION: The operation performances of a printing wire 2 and an armature 1 are determined by the spring constant and the deflection amount of a leaf spring 6. In order to control the spring constant of the leaf spring 6 with a high precision, a distance H between a core 10, a yoke 11 and the attracting surface 21 of the armature 1, and a pressing member 19 provided in a housing 14, is set to be higher than a prescribed amount. A laser beam is applied to this leaf spring 6 from the direction A through a beam hole 18 formed in the housing 14 to effect trimming so that the symmetry is obtained with respect to the center line of the leaf spring 6. By the formation of a portion 20 trimmed in this way, the sectional form of the leaf spring 6 is changed and the spring constant is lowered to a prescribed value. Then, a trimming amount 20 of each leaf spring 6 is varied separately, and adjustment is made so that the spring constants of all the leaf springs 6 may be uniform.
| JPH04120040 | [Title of the device] Wire dot printing A head |
| JP2794789 | [Title of Invention] Wire Dot Head |
ASAI KIYOTERU
FUJII TEIZO
FURUYA KANAME
