Braking system for a vehicle manual window-lifting mechanism
View Patent ↗A braking system for a vehicle manual window-lifting mechanism prevents a window from dropping as a consequence of vibrations and minimizes angular play in a crank shaft. The system includes a helical spring that assists the crank shaft and that has a geometry modified from its conventional design. An included angle between the radial side pieces at which the winding ends terminate is an acute angle. One of the side pieces is coupled inside a radial hollow of the crank-driven shaft itself. The other side piece is located between the crank shaft and the drum, which rotate relative to each other. As a result, instead of the usual 40° or 45° of free play, the invention allows a maximum free play of only 10° to 15° in the crank shaft.
1. A braking system for a manual vehicle window-operating mechanism having a drum and a crank shaft that rotate relative to each other, the braking system comprising:
a helical spring having first and second winding ends; and
a first radial side piece disposed at the first winding end and a second radial side piece disposed at the second winding end, wherein an included angle between the first and second radial side pieces is an acute angle,
and wherein the first radial side piece is adapted for receipt in a slot in the crank shaft and the second radial side piece is adapted for disposition between the crank shaft and the drum.
2. The braking system of claim 1 , wherein the acute angle between the first and second winding ends is less than 30°.
3. The braking system of claim 1 , wherein the helical spring brakes the window-operating mechanism when the second radial side piece contacts the drum.
4. A manual vehicle window-operating mechanism, comprising:
a crank shaft;
a drum, wherein the crank shaft and the drum rotate relative to each other;
a helical spring having first and second winding ends and coaxially surrounding the crank shaft and the drum; and
a first radial side piece disposed at the first winding end and a second radial side piece disposed at the second winding end, wherein an included angle between the first and second radial side pieces is an acute angle,
and wherein the first radial side piece is disposed in a slot in the crank shaft and the second radial side piece is disposed between the crank shaft and the drum.
5. The window-operating mechanism of claim 4 , wherein the acute angle between the first and second winding ends is less than 30°.
6. The window-operating mechanism of claim 4 , wherein the crank shaft comprises at least one extension, wherein the slot is formed in said at least one extension.
7. The window-operating mechanism of claim 6 , wherein said at least one extension comprises a first extension having the slot and a second extension that is diametrically opposite the first extension.
8. The window-operating mechanism of claim 4 , wherein the helical spring brakes the window-operating mechanism when the second radial side piece contacts the drum.