| 摘要 |
PURPOSE:To see that the damper rubber does not come out to race even in abnormality where great load is added to a window glass by making it into a shock absorber, which engages the projection provided in the circumference of a torque transmitting plate in the recess of the circumference of a worm wheel leaving space between them. CONSTITUTION:The usual shock arising between a warm wheel 3 and a torque transmitting plate 5 is absorbed by damper rubber 4 twisting. That is, the hardness of rubber is selected such that the helix angle of the damper rubber becomes 30 deg. or less when a window glass is closed completely or opened fully. And at abnormality, that is, when great load is applied to the window glass, the helix angle of the damper rubber 4 becomes 30 deg. or more, but at this time, the fellow circumferential faces of the recess 11 of the worm wheel 3 of synthetic resin and the projection 12 of a torque transmitting plate 5 made of steel abut on each other, so the damper rubber 4 does not cause the torsion more than it, and great torque can be transmitted. |
