Abstract: A universal lid closure for underground landscape and other utility access boxes uses flexible tongues depending from the underside of the lid and adapted to engage the interior of the access box, which box may have any one of various constructions. In one embodiment, the tongues have a plurality of diametrically opposed pairs of locking detents, each pair defining a different vertical position, to engage an annular locking shoulder on the interior of the box to secure the lid in the closed position.

Abstract: A modular filter system using replaceable filter cartridges includes matching adaptor rings in the filter head and on the filter cartridge placed at selected circumferential positions to ensure proper cartridge fit and to provide a proprietary cartridge construction for selected users. The adaptor rings operate only to control cartridge to filter head fit and are not used to drive the rotary valve spindle.

Abstract: A modular filter system using replaceable filter cartridges includes a locking arrangement that prevents rotation of the flow control valve spindle in the filter head, but includes an unlocking arrangement on the cartridge that unlocks the locking arrangement if the proper replacement cartridge is used. The locking arrangement may include spring biased locking pins carried on the filter head and matching unlocking pins on the filter cartridge to operate through an intermediate adaptor ring that is set on assembly to match the positions of the locking and unlocking pins.

Abstract: A modular filter system using replaceable filter cartridges includes matching adaptor rings in the filter head and on the filter cartridge placed at selected circumferential positions to ensure proper cartridge fit and to provide a proprietary cartridge construction for selected users. The adaptor rings operate only to control cartridge to filter head fit and are not used to drive the rotary valve spindle.

Abstract: A modular filter system using replaceable filter cartridges includes a mounting bracket for each filter cartridge and corresponding filter head that includes keyed attachment of the head to the mounting ring on the mounting bracket and modular attachment of the mounting bracket to the modular back plate. Back plates are also modular to permit assembly of a variety of multi-cartridge systems.

Abstract: A modular filter system using replaceable filter cartridges includes a locking arrangement that prevents rotation of the flow control valve spindle in the filter head, but includes an unlocking arrangement on the cartridge that unlocks the locking arrangement if the proper replacement cartridge is used. The locking arrangement may include spring biased locking pins carried on the filter head and matching unlocking pins on the filter cartridge to operate through an intermediate adaptor ring that is set on assembly to match the positions of the locking and unlocking pins.

Abstract: A rotary valve spindle for flow control in the head of a filter includes a unitary dual function seal that is carried by the spindle and seals against the inner surface of the filter head during spindle rotation between flow and no-flow positions. The dual function seal greatly simplifies manufacture and assembly of the valve.

Abstract: A cartridge for a water treatment system, effective to assist in the removal of contaminants by photocatalytic oxidation and by adsorption, includes a plurality of stacked disks, preferably made of a UV light transmissive material, which disks define circuitous flow paths for water being treated. In a preferred embodiment, the disk surfaces contacted by the water are provided with a coating of a catalyst, such as TiO2, activated by a UV light source positioned in the center of the cartridge.

Abstract: An assembly method and related subassembly for a water filter element in the housing of a replaceable filter cartridge provides for filter element insertion into the open bottom end of the housing and subsequent attachment of a retaining ring to the upper end of the element such that the element is secured against vertical drop-out until the bottom end of the cartridge can be enclosed with an end cap. The method and subassembly are particularly well adapted to cartridges in which the lower end cap is attached by spin welding. The enclosing end cap may also be provided with end rings to enhance the user's grip in cartridge installation and removal. The end rings may also be color coded for each of cartridge identification and matching to the filter head.

Abstract: The valve spindle for a reverse osmosis (RO) filter system is housed in a filter head and attached to a mounting ring that also carries the replaceable RO cartridge. The RO spindle is locked in the head during normal operation, but can be easily removed, after removal of the cartridge, to permit spindle replacement or repair without disassembly of the head from the mounting bracket.

Abstract: A universal lid closure for underground landscape boxes that universally adapts to all underground landscape box sizes by the design of flexible flaps Mat extend radially outwardly from their attachments to the lid body. The flaps are preferably of varying lengths and widths. A plurality of flexible flaps prevent accidental lid removal by exerting resilient force at a precise angle on the underground landscape box wall. A lid top is provided to enclose all box opening circumferences in each box class, and the flexible flaps are molded at a precise angle to horizontal to deter fatigue within the flexible flap.