The text and illustrations of US patents published before March 1, 1989 are in the public domain unless the patent text contains a specific notice that portions are copyrighted. See 37 CFR 1.71(d), 37 CFR 1.84(s) The original patent contains no such notice, so its contents are in the public domain. Note: This only applies to images published before March 1, 1989. Patents published after that date are most likely copyrighted, unless in the public domain for another reason, such as {{PD-ineligible}}.

这张图片属于美国政府专利号3789832 filed 17 March 1972, issued Feb 5, 1974. 图片来自美国专利商标局。

This image belongs to a US govt Patent number 3789832 filed 17 March 1972, issued Feb 5, 1974. Image is from the US Patent and Trademark Office.

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(删除该图像的所有修订版本) (当前) 16:12 2006年1月24日 . . Uvo (Talk) . . 640x388 (124565字节)