the cover and movable between a first position to cause the cover to pivot to expose at least a part of the opening and a second position to cause the cover to pivot to cover at least a part of the opening application_number US 201414286917 A description reference will be made in detail to embodiments of the present disclosure and the embodiments described herein are shown in drawings in which the same or similar elements and the elements having same or similar functions are denoted by like reference numerals throughout the descriptions in the specification it is to be understood that an orientation or position relations referred by relative terms such as u201c central u201d u201c longitudinal u201d u201c lateral u201d u201c front u201d u201c rear u201d u201c right u201d u201c left u201d u201c inner u201d u201c outer u201d u201c lower u201d u201c upper u201d u201c horizontal u201d u201c vertical u201d u201c above u201d u201c below u201d u201c up u201d u201c top u201d u201c bottom u201d u201c clockwise u201d and u201c counterclockwise u201d as well as derivative thereof should be construed to refer to the orientation or position relations as then described or as shown in the drawings under discussion these.