Abstract: A pressure vessel in the form of a hydro-pneumatic flexible bladder accumulator is provided which includes a shell formed of a cylindrical tube. An open-ended thimble-shaped deformable bladder of resilient material is positioned within the shell. A port plate is attached to one end of the tube, and a closure cap is retained in the other end of the tube. The cap may be retained in the other end of the tube, for example, by a removable locking ring. The closure cap has an inner end which may be displaced radially inwardly from the inner surface of the shell, and it has three axially spaced peripheral grooves on the inner end which respectively receive an O-ring to prevent leakage of liquid out of the accumulator, and two integral beads that surround the mouth of the bladder. One of the integral beads of the bladder has the shape of an O-ring, and it is received in one of the grooves to form an effective seal for the interior of the bladder.

Abstract: A fishing rod holder is provided which may be driven into the ground, and which includes a tubular portion for receiving the handle of a fishing rod and for supporting the rod at a desired angle so that it extends out over the body of water from which fish are to be extracted. The tubular portion includes a slot at its upper end through which the reel of the fishing line extends. An electrical indicator unit, which may include a buzzer, a light, or other electrically energized indicator, is mounted on the side of the tubular portion near its upper end. The electrical indicator unit is self-contained in a separate case, and it includes the usual batteries and electrically energized indicator. The unit also includes a spring-loaded energized trigger which extends into the tubular portion of the holder through the aforesaid slot. The handle of the fishing rod normally rests against the trigger without sufficient force to cause it to energize the electric indicator.

Abstract: A locking ring assembly is provided for releasably retaining a tubular valve housing in the liquid port of a bladder-type pressure accumulator without any possibility of the valve housing being blown out from the port when a normal high pressures are attained within the accumulator shell. The locking ring assembly seats at an angle against an identical angle on the inside of the opening at the mouth of the accumulator shell so that when excessively high internal pressures are reached within the shell the ring will force the mouth of the shell to expand diametrically forcing the mouth open thus extruding an O-ring seal which releases the pressure. Thus the accumulator shell cannot burst.

Abstract: An anti-extrusion grommet assembly is provided for releasably retaining a tubular valve housing in the liquid port of a bladder-type pressure accumulator. The grommet assembly of the invention is constructed to preclude any possibility of the valve housing from being blown out through the port in the presence of normal operating pressures within the accumulator shell. The assembly is particularly intended for use with relatively small sized accumulators of, for example, capacities of the order of one gallon.

Abstract: An open-ended accumulator is provided which may be constructed to be of a relatively large size, for example, in the 15-25 gallon range, and to be of relatively high pressure of the order, for example, of 5,000 psi. The accumulator is constructed so that its internal bladder can be replaced from one end of the shell without the need to remove the accumulator from the equipment in which it is installed. The accumulator includes a forged cap which is contoured to accept the rim of a thimble-shaped bladder within the shell, the cap being fitted within the open end of the shell. A segmented wedge-shaped tapered ring retains the cap in the shell. As outer plate may also be provided to permit the accumulator to be mounted under water without the water pressure tending to force the cap into the interior of the shell.