The present application provides a removable cover that is easily placed and secured onto a corresponding frame. The cover includes a protrusion receptacle and a protrusion cutout each located at different positions along the perimeter of the cover. The cover further includes a locking assembly, such as a worm gear assembly, that extends through cover to lock the cover to the frame. The cover also has a plurality of alignment indicators that are aligned with the protrusion receptacle and the protrusion cutout to assist an operator in securing the cover to the frame.

A hatch assembly comprising a frame presenting a frame opening, a hatch for opening and closing the frame opening, a plurality of pivot assemblies. At least two pairs of the pivot assemblies each provide a hatch pivot axis at or adjacent a side of the hatch, an engagement mechanism engagement mechanism configured to releasably engage the pivot assemblies to couple the hatch to the frame, and an actuation mechanism. The engagement mechanism comprises a plurality of pins, each pin movable between an extended position to engage a said pivot assembly and a retracted position to disengage from the pivot assembly. The pins are oriented so that longitudinal axes of the pins in each pair of pins converge enabling the hatch to remain coupled to the frame when the hatch is pivoted between the closed position and an open position.

An access cover to underground city infrastructure, particularly a cast iron or a cast iron-concrete cover provided with a cover detection sensor connected with a radio frequency signal transmitting antenna through a transmitter, characterised in that an antenna module (1) provided with a housing made of a material neutral to electromagnetic fields, preferably made of plastic, is installed in the through channel (4) with variable cross-section, and removably fixed at the bottom to a sensor module (2) located underneath the bottom of the cover (3), provided with a battery powered, low current electronic system containing a radio transmitter and an acceleration sensor or a gyroscope and an appropriate controller which detects changes to the position of cover (3) in space and in time, whereby the surface area of the sensor module (2) is greater than the surface area of the through channel (4). The object of the invention also includes a method of cover monitoring.

A device for securing a cover having an opening therethrough over a well, drywell, or like structure having an upwardly facing horizontal base surface surrounding a bottom opening of the well includes an upper member positioned on the cover, a lower member positioned horizontally upward against the horizontal base surface, and a connecting rod that operatively connects the upper to the lower member and maintains a tension force between them via the connecting rod to secure the cover in position. A connector on the rod allows the lower member to pivot to a vertical position alongside the rod for insertion through the hole in the cover. In this way, the device can be installed with the cover in situ. The connector also provides translational movement of the lower member along the rod to provide, or remove, the tension. A locking element connected to the rod allows adjusting of the tension.

A manhole cover assembly includes a manhole cover supportable by a seat of a manhole frame and a latch assembly. The latch assembly includes a latch housing, a latch bar, and a padlock. The latch housing is fixedly coupled to the manhole cover and defines a channel that extends through the latch housing. The latch bar is coupled to the channel and is slidable relative to the latch housing between a locked position and an unlocked position. The padlock is operatively coupled to the latch bar and is configured to maintain the latch bar in the locked position.

A valve box lock for preventing unauthorized access to a shut off valve including a security bolt extending through a hole in a valve box cover and received into a threaded hole in a cam piece mounted to the undersurface of the cover, the cam piece is moved up and down by rotation of the security bolt in either direction. The cam piece engages a pair of locking plates which are moved radially out into engagement with an inner surface of the valve box to prevent removal of the cover when the security bolt is rotated in one direction, or are retracted radially to release the cover so as to be able to be removed. A automatic lubricating arrangement is associated with the security bolt to insure that it is able to be turned by excluding any.

A system including a backfill protector including a skirt having an opening configured to receive a cover therein and a lip extending around a perimeter of the opening. The lip is configured to support the cover thereon, and the skirt further includes an inwardly-extending channel positioned adjacent to the lip.

A tubular insert sleeve system comprises a tubular insert sleeve for insertion into an excavated hole and a snug fitting and removable safety cover adapted to extend over the upper end of the tubular insert sleeve in order to cover the excavated hole. One or more sleeve fastening apertures are defined through the tubular insert sleeve adjacent the upper end thereof, and are adapted to receive one or more vermiform fasteners for fastening the safety cover to the tubular insert sleeve. Preferably, the sleeve fastening apertures are in the form of handles. In some embodiments, one or more cover fastening apertures are defined through the safety cover and the cover fastening aperture(s) cooperate with the sleeve fastening aperture(s) to receive the vermiform fastener(s) to fasten the safety cover to the tubular insert sleeve.

An example manhole cover assembly includes a manhole cover and a latch assembly. The manhole cover is supportable by a seat of a manhole frame. The latch assembly includes a latch housing fixedly coupled to the manhole cover. A latch plunger is slidably coupled to the latch housing. The latch plunger includes a follower arm. A latch lever is rotatably coupled to the latch housing. The latch lever includes a stop. The latch lever is rotatable relative to the latch housing between a locked position and an unlocked position. The stop is structured to engage the manhole frame when the latch lever is rotated to unlocked position so as to force the manhole cover away from the frame.

A manhole cover assembly includes a manhole cover supportable by a manhole frame, The manhole cover defines a latch bore having a longitudinal axis. A latch housing extends from the manhole cover, and a latch assembly is positioned at least partially therein. A first end of a latch yoke extends through the latch bore and slidably couples the latch yoke to the manhole cover along the longitudinal axis. A latch member is rotatably coupled to the second end of the latch yoke about a first transverse axis perpendicular to the longitudinal axis. The latch member is also rotatably coupled to the latch housing about a second transverse axis spaced from the first transverse axis. The latch member is selectively rotatable relative to the latch housing about the second transverse axis, between a locked position and an unlocked position, via sliding the latch yoke relative to the manhole cover.