Abstract: A compact pressure regulating valve makes installation work simple and has a hermetic structure of a stationary value member without a specific seal member. A pressure regulator (201) has a body (203) which includes a fuel inlet (215) and an inner periphery for positioning a stationary valve member (205) in a radial direction. When the movable valve member (208) leaves the stationary valve member (205), the valve opens. Operation of the movable valve member (208) is controlled by a diaphragm which moves to balance the pressure of the pressure chamber (211) and the pressure of a back pressure chamber (213) combined with a biasing pressure of a compression coil spring (214). As a result, the pressure of the pressure chamber (211) can be controlled without a specific sealing member or complex structure. In addition, a pressure regulating valve according to the present invention is compact and easy to install, and has no specific member to seal the stationary valve member.

Abstract: A fuel pump and a fuel filter inside a fuel tank and a pressure regulator are supported by a cover closing for an opening of the fuel tank. The fuel sucked by the fuel pump flows into the fuel filter and flows out to the lower side chamber of a filter housing after being filtered by an element. The fuel consumed at the fuel consumption device such as an internal combustion engine is supplied through a fuel passage extending upward from the lower side chamber of the filter housing. On the other hand, water mixed in the fuel is accumulated in the lower side chamber. Especially, glass fibers having high water affinity is mixed in the filter element, so that water is trapped, becomes water drops, and fall to the lower side chamber. Water drops return to the fuel tank with surplus fuel through the pressure regulator disposed at the bottom of the housing.

Abstract: An oil deterioration detector comprising a sensitive electrode whose electric potential varies in response to acidity and/or basicity of oil to be measured, and a reference electrode associated with this sensitive electrode. An electrically conductive housing accommodates the sensitive electrode and the reference electrode together with the oil. A potential difference detector detects oil deterioration by measuring a potential difference between the sensitive electrode and the reference electrode. And, an insulating member is interposed between these electrodes and the electrically conductive housing for electrically insulating these electrodes from the electrically conductive housing. The reference electrode is grounded together with the electrically conductive housing. An insulating, hydrophilic porous member would be interposed between the sensitive electrode and the reference electrode.