This invention relates to a filter with a valve-in-head construction. The filter is adapted for household and other uses for filtering fluid flowing through a pipeline. The above identified patents illustrate filters of this general type. Normally, such filters include an outer housing which is adapted to receive a replaceable filter cartridge. One end of the housing is closed, while the other end is adapted to receive a removable valve head which connects to the fluid line for selective fluid flow through the filter.
Various constructions of valve heads are shown in the above patents. Some of them, such as U.S. Pat. No. 3,777,889, include an annular "stand pipe" which telescopes into the core portion of the filter to locate it. Some also include inlets and outlets which are diametrically opposed, as in U.S. Pat. No. 4,271,020. Others, such as U.S. Pat. No. 3,853,761, utilize suitably actuated sliding spools which control the fluid flow within the valve. Some known devices also provide a bypass of portions of the fluid around the valve, even when it is in the "off" position.
It is an object of the present invention to provide a valve-in-head filter arrangement which is improved over the previously known structures.
In accordance with the various aspects of the invention, the device is for use with an outer housing adapted to receive a fluid filter cartridge therein. A valve head is provided which includes an annular stand pipe for locating an end of the filter. The stand pipe is cut away on its downstream side to reduce fluid back pressure. Furthermore, a passage is disposed between the head inlet and outlet, with the passage receiving a slideable plunger therein. An actuatable device connects through a rotary actuator to move the plunger. The actuator includes a stem mounted eccentrically to the handle axis, with the stem received in a recess in the plunger so that turning of the handle moves the plunger between "on" and "off" positions. The plunger includes a seal which continuously engages the passage wall in all plunger positions, and the construction provides full "on" and "off", with no fluid bypass in the "off" position.