Sealing cover

Abstract

A sealing cover includes a base, a lower lid, and a soft, deformable gasket mounted between outer peripheries of the base and the lower lid. An upper lid includes a positioning hole having an inner periphery with higher and lower positioning grooves, with a lower positioning groove located between two adjacent higher positioning grooves. A positioning ring includes upper and lower positioning protrusions. The upper lid can be pressed and moved downward relative to the lower lid, so that the pressing member presses against the upper positioning protrusions of the positioning ring, causing rotational movement of the positioning ring through an angle and changing the spacing between the base and the lid. When the upper lid is released, the upper positioning protrusions are engaged in higher positioning grooves or the lower positioning grooves so that the sealing cover is in a sealing state or an unsealing state.

1 . A sealing cover comprising:
 a sealing unit including a base, a gasket, and a lower lid, with each of the base and the lower lid including an engagement edge, with the lower lid mounted on top of the base, with the lower lid movable relative to the base in a vertical direction to change a spacing between the engagement edge of the base and the engagement edge of the lower lid, with the gasket made of a soft and deformable material, with the gasket mounted between the engagement edges of the base and the lower lid; and   a control unit including a seat, a pressing member, an upper lid, and a positioning ring, with the seat fixed to the base, with the seat including a plurality of annularly spaced upper abutment protrusions and a plurality of annularly spaced lower abutment protrusions, with an upper groove defined between two adjacent upper abutment protrusions, with a lower groove defined between two adjacent lower abutment protrusions, with the pressing member mounted on the seat and movable in the vertical direction, with the pressing member including an upper end having a plurality of teeth, with the upper lid mounted on top of the lower lid and including a positioning hole, with the positioning hole including an inner periphery having a plurality of annularly spaced higher positioning grooves and a plurality of annularly spaced lower positioning grooves, with each of the plurality of lower positioning grooves located between two adjacent higher positioning grooves, with the positioning ring mounted in the positioning hole of the upper lid, with the positioning ring including a lower end having a plurality of lower positioning protrusions corresponding to the plurality of upper abutment protrusions and the plurality of lower abutment protrusions, with the positioning ring including an upper end having a plurality of upper positioning protrusions corresponding to the plurality of higher positioning grooves and the plurality of lower positioning grooves,   wherein when the upper lid is pressed and moved downward relative to the lower lid, the plurality of teeth of the pressing member presses against the plurality of upper positioning protrusions of the positioning ring, causing rotational movement of the positioning ring through an angle, with the spacing between the abutment edges of the base and the lid being changed,   wherein when the upper lid is released, the upper lid is moved upward by resilience of the gasket, moving the plurality of upper positioning protrusions of the positioning ring into the plurality of higher positioning grooves or the plurality of lower positioning grooves, with the plurality of lower positioning protrusions aligned with the plurality of upper abutment protrusions or the plurality of lower abutment protrusions of the seat,   wherein the gasket is not squeezed and does not extend beyond the outer periphery of the base when the plurality of upper positioning protrusions is engaged in the plurality of lower positioning grooves, such that the sealing cover is in an unsealing state,   wherein the gasket is squeezed and extends beyond the outer periphery of the base when the plurality of upper positioning protrusions is engaged in the plurality of higher positioning grooves, such that the sealing cover is in a sealing state.   
     
     
         2 . The sealing cover as claimed in  claim 1 , with the upper grooves of the seat not aligned with the lower grooves of the seat, with the plurality of lower positioning protrusions inserted through the upper and lower grooves of the seat in an inclined angle to a position aligned with the plurality of lower abutment protrusions or the plurality of upper abutment protrusions. 
     
     
         3 . The sealing cover as claimed in  claim 2 , with the base further including a central portion having an abutment face and an engaging portion, with the lower lid including a bottom wall and an annular wall formed along an outer periphery of the bottom wall, with the bottom wall of the lower lid including a central portion having a through-hole aligned with the abutment face of the base, with the seat fixed to the engaging portion of the base, with the pressing member being annular and having a diameter larger than a diameter of the seat, with the pressing member mounted around the seat and aligned with the through-hole of the lower lid, with the pressing member including a lower, abutment end abutting the abutment face of the base, with a guiding protrusion provided on an outer periphery of the pressing member, with each of the plurality of teeth of the pressing member having an inclined guiding face, with the upper lid including an annular wall mounted around the annular wall of the lower lid, with each of the plurality of higher positioning grooves including a slant, with the guiding protrusion of the pressing member received in one of the plurality of higher and lower positioning grooves to restrain movement of the pressing member in the vertical direction, with the positioning ring including a through-hole in which the seat is received, with each of the plurality of upper positioning protrusions including an inclined guiding face for engaging with one of the inclined guiding faces of the pressing member and one of the slants of the positioning hole of the upper lid. 
     
     
         4 . The sealing cover as claimed in  claim 3 , with the base including a top face having a plurality of pivotal columns, with the lower lid including a plurality of slots, with the plurality of columns extending through the plurality of slots of the lower lid, with the two supports mounted on top of the bottom wall of the lower lid, with the two supports including a plurality of pivots pivotably engaged with the plurality of pivotal columns, with each of the two supports including a first side having an abutment portion abutting the bottom wall of the lower lid, with each of the two supports including a second side having a pressing portion abutting the upper lid. 
     
     
         5 . The sealing cover as claimed in  claim 3 , with the top face of the base including an annular groove, with a first spring received in the annular groove and having a first end abutting a bottom wall of the annular groove and a second end abutting the lower lid. 
     
     
         6 . The sealing cover as claimed in  claim 3 , with the bottom wall of the lower lid including a plurality of receiving holes, with a plurality of second springs received in the receiving holes. 
     
     
         7 . The sealing cover as claimed in  claim 3 , further comprising: a shield mounted on top of the upper lid, with the shield covering the positioning ring and the seat. 
     
     
         8 . The sealing cover as claimed in  claim 7 , with the positioning ring including an upper annular portion having a plurality of annularly spaced indexes, with the shield including at least one window allowing viewing of at least one one of the plurality of indexes. 
     
     
         9 . The sealing cover as claimed in  claim 7 , with the positioning ring including a lower annular portion, with a third spring mounted between the lower annular portion and the shield.