| 摘要 |
PURPOSE:To effectively suppress the vibration of an armature by fixing a reset spring composed of leaf springs having cut grooves of no directivity in an airtight housing at the back of the armature and causing the reset spring to perform viscous damping. CONSTITUTION:A reset spring 24 to which one end of a print element wire 21 is connected is arranged in an airtight housing 23 at the back of an armature 19. Also the outer circumference of the reset spring 24 is fixed and supported between the shoulder 25 and the upper lid 26 of the airtight housing 23 and the reset spring 24 also divides the airtight housing 23 into 2 air chambers 27, 28. By this arrangement, when the reset spring 24 makes vibration interconnected with the armature 19 within the airtight housing 23, the air inside of both air chambers 27, 28 is caused to flow reciprocately only through cut grooves 12, 17 provided on the reset spring 24, and at this time air plays the role of a resistor and the vibration of the armature 19 is monentarily attenuated. |
