| 摘要 |
The portable sign includes a display frame, a base having shafts for pivotably mounting the display frame on the base, first and second stops, one positioned on one side of the base, the other positioned diagonally across on the opposite side of the base. The spring structure has two springs, each engaging and winding only in one direction to prevent unwinding of the spring. Upon application of a force such as the wind to the display frame, the first spring engages the adjacent stop and tightens while the second spring disengages from the adjacent stop and rotates away from the stop. This allows deflection of the frame while protecting the spring from being unwound. A second embodiment of the portable sign includes a display frame, a base having shafts for pivotably mounting the display frame on the base, and a spring mechanism for biasing the display frame including a first bracket for retaining a spring, a spring, and a second bracket for slidably retaining a spring. The spring mechanism is mounted at one end to the display frame and the other end the base so that when a force deflects the display frame, the spring flexes and slides through the second bracket for slidably retaining a spring and when the force ceases, the spring unflexes and shortens and acts to restore the display frame to an upright position.
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