Abstract: An apparatus for drilling into a pipe under pressure to form a branch has a casing which can be connected to an isolating valve of a tee-fitting and through which a drill bit passes within the tee-fitting and the valve. The drill bit is surrounded by a barrel sealed with respect to the casing so that the casing rearwardly of the drill bit forms a chamber receiving drilling debris.

Abstract: An improved wheel assembly is provided for use with a shopping cart or the like to restrain the cart against rolling movement when parked. The improved wheel assembly comprises a wheel rotatably supported on the cart or the like by a friction bearing unit which imparts a predetermined frictional resistance to rolling movement of the wheel. The magnitude of the frictional resistance is chosen to prevent the cart from rolling about when parked, for example, on a gentle slope while permitting the cart to be pushed about in a normal manner.

Abstract: In an automobile door hinge which includes a leaf mounted on the body and a leaf mounted on the door, the leaves having parallel overlapping flanges, with a hinge pin in aligned holes in the flanges, hinge plates are secured to the flanges of the body leaf with sealed ball bearings receiving the hinge pin.

Abstract: This improved powder-actuated fastener driving tool includes a fastener-driving piston which is slidably housed in a reciprocating barrel. The barrel is contained in a housing member. The tool includes a movable firing pin slidably disposed in a movable breech member. A firing pin pawl is retained in a slot in the breech member to hold the firing pin in a cocked position. The firing pin is held in place in the breech member by a removable C ring disposed in a groove in the firing pin spring guide. Auxiliary gas-venting passages are disposed in the housing tool barrel adjacent a piston pawl return slot formed in the barrel. The tool includes a tapered muzzle bushing which reduces the possibility of air-firing the tool. The inner or breech end of the muzzle bushing is spaced from the muzzle end of the barrel to minimize the possibility of deformation of the muzzle bushing due to piston overdrive.