A liquid filtering device that works in conjunction with an existing filtration system to provide, for example, cleaner water in a swimming pool.

A fuel filter has a filter housing and a fuel filter insert exchangeably arranged in the filter housing and provided with a prefilter element and a main filter element. Prefilter element and main filter element are positioned one behind the other in the filter housing in axial direction of the filter housing. A fuel discharge channel is arranged in the filter housing below the fuel filter insert. In operating position of the fuel filter insert in the filter housing, the raw sides of prefilter element and of main filter element are sealed relative to the fuel discharge channel by seal-tight contact of the fuel filter insert on the filter housing. The raw side of the main filter element, when the fuel filter insert is moved by axial movement away from the operating position, is fluidically connected with the fuel discharge channel via the raw side of the prefilter element.

A fuel filter has a filter housing and a fuel filter insert exchangeably arranged in the filter housing and provided with a prefilter element and a main filter element. Prefilter element and main filter element are positioned one behind the other in the filter housing in axial direction of the filter housing. A fuel discharge channel is arranged in the filter housing below the fuel filter insert. In operating position of the fuel filter insert in the filter housing, the raw sides of prefilter element and of main filter element are sealed relative to the fuel discharge channel by seal-tight contact of the fuel filter insert on the filter housing. The raw side of the main filter element, when the fuel filter insert is moved by axial movement away from the operating position, is fluidically connected with the fuel discharge channel via the raw side of the prefilter element.

A fuel filter insert for a fuel filter has a low-pressure region with prefilter element arranged therein. A high-pressure region arranged fluidically downstream of the low-pressure region has a main filter element arranged therein. Prefilter element and main filter element are arranged one atop the other axially in the fuel filter insert. A wall element projects away from the main filter element in axial direction and extends at least partially through the prefilter element. Low-pressure region and high-pressure region at least over sections thereof are separated from each other by the wall element. A fuel filter is provided with a filter housing in which the fuel filter insert is arranged. The filter housing has a fuel outlet and a fuel inlet for fuel prefiltered by the prefilter element. Fuel inlet and fuel outlet are fluidically positioned between low-pressure region and high-pressure region and a fuel pump is connectable thereto.

A fuel filter insert for a fuel filter has a low-pressure region with prefilter element arranged therein. A high-pressure region arranged fluidically downstream of the low-pressure region has a main filter element arranged therein. Prefilter element and main filter element are arranged one atop the other axially in the fuel filter insert. A wall element projects away from the main filter element in axial direction and extends at least partially through the prefilter element. Low-pressure region and high-pressure region at least over sections thereof are separated from each other by the wall element. A fuel filter is provided with a filter housing in which the fuel filter insert is arranged. The filter housing has a fuel outlet and a fuel inlet for fuel prefiltered by the prefilter element. Fuel inlet and fuel outlet are fluidically positioned between low-pressure region and high-pressure region and a fuel pump is connectable thereto.

A filter system for filtering a fluid has a filter housing with filter housing head module and housing cover. The filter housing accommodates a filter element with raw side and clean side. A fluid inlet is in fluid connection with the raw side of the filter element. A fluid outlet is in fluid connection with the clean side of the filter element. The filter housing head module has a tube section as a main channel connecting the clean side of the filter element to the fluid outlet when the housing cover is attached to the filter housing head module. The tube section projects into the clean side of the filter element and has a ball valve seat of a ball valve for closing or opening the main channel. The filter housing head module has a pump chamber of a pump as a bypass channel bypassing the ball valve seat.

A filter system for filtering a fluid has a filter housing with filter housing head module and housing cover. The filter housing accommodates a filter element with raw side and clean side. A fluid inlet is in fluid connection with the raw side of the filter element. A fluid outlet is in fluid connection with the clean side of the filter element. The filter housing head module has a tube section as a main channel connecting the clean side of the filter element to the fluid outlet when the housing cover is attached to the filter housing head module. The tube section projects into the clean side of the filter element and has a ball valve seat of a ball valve for closing or opening the main channel. The filter housing head module has a pump chamber of a pump as a bypass channel bypassing the ball valve seat.

A machine, a filtration system and a method for disinfection and purification in fuel tanks located in places with high humidity or high relative humidity, having a machine (1) with an inlet for the fuel from the tank, a filtration system of a coarse-grain filter (2) and a fine-grain filter (2′); a radiation chamber (3) configurable for the application of radiation to the filtered fuel; a pump (4); a flowmeter (5) with at least two electrovalves (17); a centrifuge (6) with a turbine filter (6′) and control via an electrical panel (7); a cleaning machine (1); a suction hose (8) with an extendable suction lance (9); a high-pressure discharge hose (11); a return hose (12); a system for the opening and sealing of the tank (25); and an automatic filter self-cleaning system which reverses the flow, sending the fouled fuel to an additional tank (14) where it is drained.

A machine, a filtration system and a method for disinfection and purification in fuel tanks located in places with high humidity or high relative humidity, having a machine (1) with an inlet for the fuel from the tank, a filtration system of a coarse-grain filter (2) and a fine-grain filter (2′); a radiation chamber (3) configurable for the application of radiation to the filtered fuel; a pump (4); a flowmeter (5) with at least two electrovalves (17); a centrifuge (6) with a turbine filter (6′) and control via an electrical panel (7); a cleaning machine (1); a suction hose (8) with an extendable suction lance (9); a high-pressure discharge hose (11); a return hose (12); a system for the opening and sealing of the tank (25); and an automatic filter self-cleaning system which reverses the flow, sending the fouled fuel to an additional tank (14) where it is drained.

A filter device for a water-bearing domestic appliance which has a surface filter with a sleeve shape, a support structure for said surface filter and a flow-through filter housing with filter inlet and filter outlet. The surface filter is held stably on the support structure, which has through-flow openings and a central opening at the end. A first flow path for water leads into the support structure and out again through the through-flow openings and the surface filter. A second flow path leads into the support structure and out again only through the central opening. The support structure is designed circumferential and is formed by support ribs which between them comprise the through-flow openings. The surface filter is attached or pressed onto the outside of the support structure in such a way that it covers the through-flow openings and rests on the outside of the support ribs.