Locking valve cover

In locking cover apparatus, wherein the cover is comprised of a top plate positioned on, and closing the top end of a downwardly extending ring, and a plurality of radially moveable, elongated lugs positioned under the top plate and extending radially through respective holes through the ring, the improvement comprising:

• a rotatable driver extending through, and rotatably mounted in, a hole in the top plate, wherein said rotatable driver has an upper portion and a lower portion, the upper portion of which is rotatably mounted to said top plate and the lower portion of which extends downwardly through said hole in said top plate;
• crank means under said top plate and adjacent said rotatable driver and connected to said lugs for radially extending and retracting said lugs in relation to said ring, wherein said crank means is connected in rotatable relation to said lower portion under said top plate;
• and
• lock means positioned in said driver and accessible and operable from above the top plate for releasably connecting said driver to said crank means, wherein said lock means has releasable latch means operable from above said top plate for releasable latching said driver and said crank means together in rotatably immovable relation to each other so that rotation of said driver with respect to said top plate also causes rotation of said crank means with respect to said top plate, said lugs being connected to said crank means in such a manner that rotation of said crank means in one direction radially extends said lugs and rotation of said crank means in the opposite direction radially retracts said lugs.

In locking cover apparatus, wherein the cover is comprised of a top plate positioned on, and closing the top end of a downwardly extending ring, and a plurality of radially moveable, elongated lugs positioned under the top plate and extending radially through respective holes through the ring, the improvement comprising:

• a rotatable driver rotatably mounted under the top plate;
• a crank positioned under said top plate and adjacent said rotatable driver, said crank being rotatable about an axis, said lugs being connected at their proximal ends to said crank eccentric to said axis and with the distal ends of said lugs positioned in respective ones of said holes through said ring such that rotation of said crank about said axis moves the distal ends of said lugs radially with respect to said axis and with respect to said ring, said lugs being beveled on one lateral side adjacent the distal ends, said beveled side defining a beveled face perpendicular to the plane of extension of said lugs, and the clearance between said lugs and the ring in said holes being close enough such that the lug goes into a bind with the ring and cannot be withdrawn from the ring when forced one direction by said eccentric mounting to the crank, but not close enough to cause such a bind with the beveled side when forced in the opposite direction so that they can be withdrawn by rotating the crank about the axis in the opposite direction;
• and
• lock means positioned in said driver and accessible and operable from above the top plate for releasably connecting said driver to said crank.

In locking cover apparatus, wherein the cover is comprised of a top plate positioned on, and closing the top end of a downwardly extending ring, and a plurality of radially moveable, elongated lugs positioned under the top plate and extending radially through respective holes through the ring, the improvement comprising:

• a rotatable driver rotatably mounted under the top plate;
• crank means under said top plate and adjacent said rotatable driver and connected to said lugs for radially extending and retracting said lugs in relation to said ring, wherein said crank means is rotatable about an axis and there are at least three lugs each of said lugs being connected at its proximal end to said crank means eccentrically with respect to said axis and in the same plane, which is perpendicular to the axis, and with the distal end of each lug positioned in one of said holes through said ring, said lugs being long enough so as not to have their distal ends completely withdrawn from said holes in said rings when said crank means is rotated about said axis enough to bring the proximal end of one lug into contact with the side of the next adjacent lug;
• and
• lock means positioned in said driver and accessible and operable from above the top plate for releasably connecting said driver to said crank means.

In a valve cover having a top portion and a side wall portion, and having a locking mechanism comprising locking lugs that engage retention means in a pipe, the improvement comprising:

• said valve cover having a central hole in said top portion for mounting a locking mechanism within;
• guide holes within said side walls for receiving said locking lugs;
• a rotor and a crank, each of which has an aperture that can be engaged so as to turn the locking lugs into and out of a locked position;
• a locking cylinder having engaging means for simultaneously engaging said aperture of said rotor and said crank so as to rotate both simultaneously, said engaging means being able to disengage the aperture of said rotor from the aperture of said crank so that said crank cannot rotate to disengage said locking lugs.

A method for locking valve covers that are adapted for placement of said valve covers in receiver means such as a pipe, said receiver means having retention means, the method comprising the steps of:

• locking said valve cover by rotating a lock cylinder so as to extend a lock cylinder tongue through apertures in a rotor and a crank, so that said rotor and said crank rotate as a unit;
• rotating said rotor so as to rotate said crank, in turn moving locking lugs radially into a fully extended position;
• engaging retention means by said locking lugs so that the valve cover is held forcibly in place by said locking lugs;
• then
• securing said valve cover by rotating said lock cylinder in a direction so as to disengage said lock cylinder tongue from the aperture of said crank so that the crank no longer rotates as a unit with said rotor, and rotation o said rotor will not in turn retract said locking lugs.