| 摘要 |
PURPOSE:To simplify the manufacture of the titled device and to improve the strength of a valve stem by providing a spring holder, which is engaged with the terminal portion of a valve stem at the bottom portion thereof and fixed thereto and has a gap left between the other end thereof and an intake cylinder. CONSTITUTION:A spring holder 32 comprising a bottomed cylindrical portion 32a, which has a flange portion 32c at the other end thereof, is engaged with the shaft end portion 22a of a valve stem at the bottom portion 32b by fitting and fixed thereto. Further an engaging member 33 is engaged with the shaft end portion 32a of a valve stem by fitting and fixed thereto. An inner torsion coil spring 31 is disposed between the shaft end portion 22a of the valve stem 22 and the spring holder 32, and an outer torsion coil spring 36 is disposed in the outer periphery of the spring holder 32, whereby the axial shifting is restrained by a flange portion 32c. The other ends of both torsion coil springs 31, 36 are engaged with the engaging member 33, and each one end thereof is engaged with a spring peg 28 of an intake cylinder 21. Thus it is not necessary to provide a notch on the spring holder 32, and a notch engaging portion of the valve stem 22 is formed only at the shaft end portion 22a, so that the manufacture can be simplified and lowering of mechanical strength can be avoided.
|
