Abstract: A gas tank cap has an inner part connectable to a gas tank filler pipe and an outer part biased outwardly away from the inner part by a spring and normally freely rotatable relative to the inner part. One or more passages in the cap communicate with the filler pipe and with the ambient atmosphere and have valves interposed in them which are so positioned that when the outer part is pushed towards the inner part the valves are automatically opened to vent pressure from the gas tank. Only after the valves have opened in response to pushing of the outer part towards the inner part do the two parts become coupled for subsequent joint rotation so as to permit removal of the gas cap from the filler pipe.

Abstract: A safety locking cover assembly for the dome of a tank truck of the type adapted to carry inflammable liquids. A cover is hinged upon a base attachable to the tank dome, and is moved between opened and closed positions by upward pivotal movement of a semicircular handle. The opposite ends of the handle pivot upon a locking bar extending beneath the cover top. The ends of the bar project from opposite sides of the cover and extend into recesses in catches mounted to the base, thereby normally preventing upward movement of the cover relative to the catches. However, the catches are spring biased against the base and are upwardly movable against the spring bias by high internal tank pressures. This provides a relatively large vent opening to vent the tank despite the fact that the handle may be closed. The cover can be manually opened by pivoting the handle through a 180.degree. arc. This moves the locking bar downwardly relative to the catches on the base.

Abstract: A pressure cooker has a pan with a circumferential rim and a lid with a closure part rotatable concentrically thereto for locking the lid on the pan part in a pressure tight manner. The lid and closure part have peripheral flanges each engaging under the edge of the pan part over a maximum of half the length thereof. The flanges are movable into one another and are arranged so that the pan rim can be released from the flanges at least over half its circumference.

Abstract: A closure for a large diameter circular opening such as the end of a tubular conduit subjected to internal positive pressure comprises a coaxial cover lid that may be opened only when a pressure relieving venting valve is opened, the cover lid being connected over the opening by screw threaded means of larger diameter than the inside diameter of the opening, and the venting valve having a removable closure cap which impedes removal of the lid until the internal pressure is vented.

Abstract: Method and apparatus for plugging a dry section of a pipeline in response to an influx of water into another section thereof while the pipeline is being laid on a sea bottom comprising; a carriage disposed in the pipeline and including a partition having forward and rearward sides with the forward side being exposed to water which may enter the other pipeline section; means for effecting a seal between the internal wall of the pipeline and the carriage; means for disengageably engaging the internal wall of the pipeline to lock the carriage against movement relative thereto, and means responsive to an influx of water into the other pipeline section on the forward side of the partition to procure actuation of the seal means and the engaging means independently of the partition to sealably lock the carriage in the pipeline with consequent plugging of the first mentioned pipeline section.

Abstract: A pressure cooker has a receptacle and a lid having a gasket around its perimeter for engagement with the upper edge of the receptacle. A bar extends across the lid and is connected to the receptacle. A spindle is threaded in the bar and engages the lid to force the lid gasket against the receptacle to seal the pressure cooker. The lid has a flexible inner liner which functions in part as a diaphragm to operate an interlock to block the rotation of the spindle when the pressure within the receptacle exceeds a predetermined value. The spindle also has a cooperating safety nut which is normally non-functional but in the event of the wearing of the operational threads associated with the spindle will warn the operator of that condition and in the event of the stripping of the operational threads will prevent the lid from opening more than a very small amount.

Abstract: The specification describes a pressure-cooker with pot and lid parts which can be turned in relation to each other and can be connected with each other by means of a bayonet joint or the like. Pot lid handles can be locked with each other and a pressure limiting valve which is adapted to be loaded by a spring and is arranged on the lid. The loading spring of the pressure limiting valve is preloaded in accordance with the locking together of the pot and lid handles.

Abstract: An improved cover support and operating mechanism is disclosed for use with the cooking vessel of deep fat frying apparatus. The vessel has an opening and the cover is supported in a plane transverse to the axis of the opening by a cross bar and a pair of vertical posts which are vertically reciprocable relative to the vessel to move the cover between open and closed positions. A spring arrangement is provided for biasing the post and thus the cover toward the open position, and a hand actuable latching arrangement is provided to releaseably hold the cover in the closed position against the spring bias.

Abstract: The radiator comprises a radiator cap for closing a cooling medium supply port, valve means for permitting the interior of a radiator body to communicate with the open air, locking means operatively associated with the valve means and for locking the radiator cap to the radiator body, and a key for actuating the locking means, whereby the valve means is opened simultaneously with the time when the locking means has been unlocked by the key.