| 摘要 |
PURPOSE:To enable free setting of a stress and a strength of an elastic part of a torsion bar and to dispose an armature and a support element in a narrow space so as to make a head small in size, by narrowing the width of the base part of the armature or the width of the support element so that a wide expanded space part be formed between them. CONSTITUTION:A thin plate part 19 having a narrow width W' is formed in the end part on the base part side of an armature 8, the width W'' of a support element 14 is made narrower than the width W of the central part of the armature 8, and thereby an expanded space part 20 is formed between the lateral side of the thin plate part 19 of the armature 8 and the support element 14. A torsion bar 15 is fitted in a U-shaped groove 16 formed of the armature 8 and the support element 14. By fusing a solder material inserted in the groove 16, the torsion bar 15 is welded to the armature 8 and the support element 14. The formation of the wide expanded space port 20 makes it possible to give a margin to the length L in the axial direction of an elastic part 18 of the torsion bar 15, and thereby a stress and a strength of the elastic part 18 are set freely. |
