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Notice: Undefined index: HTTPS in /www/wwwroot/mengmianren.com/wp-content/plugins/dessky-cache/dessky-cache.php on line 43 同一基圆的两同向渐开线为等距线;同一基圆的两反向渐开线也为等距线;齿轮的法向齿距等于其基圆齿距 – 萌面人博客