FILTER FOR DIESEL ENGINE FUEL

Abstract: A filter (1) for Diesel engine fuel comprising a filtering mass (5) which is contained within an enclosure (2) so as to be crossed by the fuel in its path inside the filter (1) between an intake connector (3) and a discharge connector (4), the filtering mass (5) being provided with provisions for separating the water contained in the Diesel fuel. The enclosure (2) comprises a water collection chamber (6) at the bottom thereof. The filter (1) comprises a pilot-operated valve (7) which is associated with the bottom of the enclosure (2) and is adapted to control a duct (8) for conveying the water to a specifically provided container. The valve (7) has at least one built-in-water level sensor (9) adapted to control the system that operates the valve (7).

Description: FILTER FOR DIESEL ENGINE FUEL Technical Field The invention relates to a filter for Diesel engine fuel. Background Art It is known that 'filters inserted on the supply circuit of Diesel engine fuel, commonly known as Diesel fuel, comprise, inside an enclosure, a filtering mass provided with means adapted to separate the water contained in said fuel: while the Diesel fuel circulates inside the filter between an intake connector and a discharge connector, encountering such filtering mass, the separated water collects on the bottom of the enclosure of the filter in order to be evacuated periodically. Accordingly, for this purpose there is a duct for connection to an appropriately provided container which is controlled by a pilot-operated valve, such as an electric or a pneumatic valve, activated by a sensor which has an independent surface and which, by detecting that the water has reached a maximum level, sends an opening command to such valve; when the minimum level is reached, the same sensor, or a different one, sends a closure command in order to prevent the escape of Diesel fuel. Any anomaly in the pilot-operated valve is indicated by a warning indicator on the vehicle dashboard which lights up and remains lit when the sensor detects the presence of water; in normal operation, such an indicator switches off immediately after the valve has opened, with a consequent drop in the level of water. Disclosure of the Invention In the prior art, the installation of a system as described above burdens significantly the cost of the entire filter; accordingly, the aim of the present invention is to provide a filter for Diesel engine fuel in which the installation of the pilot-operated valve with the corresponding sensor achieves a limited cost. Within this aim, an object of the invention is to provide a filter which allows to simply and rapidly remedy any malfunctions of the pilot-operated valve and can be easily drained in any situation. This aim and this and other objects which will become better apparent hereinafter are achieved by a filter for Diesel engine fuel, according to the invention, comprising a filtering mass which is contained within an enclosure and is designed to be crossed by the fuel in its path inside the filter between an intake connector and a discharge connector and is provided with means for separating the water contained in the Diesel fuel, said enclosure comprising a water collection chamber at the bottom, characterized in that it comprises a pilot-operated valve which is associated with the bottom of the enclosure and is adapted to control a duct for conveying the water to a specifically provided container, such valve having incorporated therein at least one water level sensor which is adapted to control the system that operates the valve. Brief description of the drawings Further characteristics and advantages of the invention will become better apparent from the description of two preferred but not exclusive embodiments of the invention, illustrated only by way of non-limitative examples in the accompanying drawings, wherein: Figure 1 is a partial sectional view of the filter according to the invention in normal operation; Figure 2 is a view of a portion of the filter according to the invention in a different condition; Figure 3 is a view of a portion of the invention according to another embodiment. Ways to carrying out the Invention With reference to Figures 1 and 2, the reference numeral 1 generally designates a filter which comprises a per se known structure which is adapted to determine, inside the enclosure 2, the circulation of the Diesel fuel indicated by the arrows in the figure between the intake connector 3 and the discharge connector 4, passing through the filtering mass 5; the water contained in the Diesel fuel is retained by an appropriately provided means, not shown in the figure, which is comprised within the filtering mass 5, and falls into the water collection chamber 6 provided at the bottom of the enclosure 2. The reference numeral 7 further designates an electric valve which is associated, by means of a bayonet coupling, with the bottom of the enclosure 2 so as to control the duct 8 for conveying the water to an appropriately provided container and is provided with the variable- resistance sensor 9 incorporated therein and sends a signal to the system that operates the valve in order to actuate the opening of the valve, with consequent passage of the water into the portion of space 8a, which gives access to the duct 8, when the water reaches the maximum level 6a shown in the figure, and sends a valve closure signal when the water reaches the minimum level, so as to avoid escape of Diesel fuel. It is noted first of all that the system that operates the electric valve 7 can equally be comprised within the control devices installed on board the vehicle equipped with the filter or be incorporated within the electric valve proper. The normal operating condition is shown in Figure 1: the electric valve 7 is arranged so that the reference teeth, such as 10, are inserted in the slots, such as 11, which are formed in a protrusion of the enclosure, and the gasket 7a ensures watertightness between the collection chamber 6 and the portion of space 8a that gives access to the duct 8. In case of malfunction of the electric valve 7, indicated by a warning light on the dashboard of the vehicle on which the filter is installed, or for example when the filter is disassembled, the user proceeds manually, causing the lowering of the electric valve to the position shown in Figure 2, with insertion of the teeth such as 10 in the slots such as 12, thus clearing the connection between the collection chamber 6 and the portion of space 8a, so as to allow the water to escape through the duct 8; in this step the gasket 7b is active. In the embodiment shown in Figure 3, the only variation with respect to what has been described above consists in that the electric valve 13 is provided with two built-in sensors, specifically the sensor 14, which detects the maximum level of the water in the collection chamber 6 and sends a signal for opening the electric valve, and the sensor 15, which sends a signal for closing the electric valve when the minimum level is reached. The described invention is susceptible of numerous other modifications and variations, all of which are within the scope of the appended claims: thus, for example, the electric valve can be replaced with a pilot-operated valve of any kind, such as for example a pneumatic valve. The pilot-operated valve may also control the water conveyance duct when it is in the lowermost position of its stroke and the connection between the bottom of the container and said duct can be opened by moving said valve to the uppermost position. The valve can further be stably associated with the bottom of the filter, and in this case its flow control element can be provided with manual actuation means for interventions in case of malfunction. In the practical execution of the invention, all the details may be replaced with other technically equivalent elements; the materials used, as well as the shapes and the dimensions, may further be any according to requirements. The disclosures in Italian Patent Application No. MI2000A001311 from which this application claims priority are incorporated herein by reference.

Claims: CLAIMS 1. A filter for Diesel engine fuel, comprising a filtering mass (5) which is contained within an enclosure (2) and is designed to be crossed by the fuel in its path inside the filter between an intake connector (3) and a discharge connector (4) and is provided with means for separating the water contained in the Diesel fuel, said enclosure (2) comprising a water collection chamber (6) at the bottom, characterized in that it comprises a pilot-operated valve (7) which is associated with the bottom of the enclosure (2) and is adapted to control a duct (8) for conveying the water to a specifically provided container, the valve (7) having incorporated therein at least one water level sensor (9) which is adapted to control the system that operates the valve (7). 2. The filter according to claim 1, characterized in that the pilot-operated valve (7) comprises a built-in variable-resistance sensor (9) which is adapted to send to the system that operates the valve (7) a maximum water level signal and a minimum water level signal so as to actuate the opening and the closure of said valve (7), respectively. 3. The filter according to claim 1, characterized in that the pilot-operated valve (7) comprises a built-in maximum water level sensor (14) and a built- in minimum water level sensor (15) which are adapted to send to the system that operates the valve (7) a signal for opening and closing said valve (7), respectively. 4. The filter according to one or more of the preceding claims, characterized in that the pilot-operated valve (7) is an electric valve with a driving system which is comprised within the control devices installed on board the vehicle equipped with the filter (1). 5. The filter according to one or more of the preceding claims, characterized in that the pilot-operated valve (7) is an electric valve with a control system which is built into said valve (7). 6. The filter according to one or more of the preceding claims, characterized in that the pilot-operated valve (7) is associated with the bottom of the enclosure (2) of the filter (1) and is movable by manual actuation between two end positions, respectively for blocking the water conveyance duct (8) and for opening the connection between the bottom of the enclosure (2) and said duct (8). 7. The filter according to one or more of the preceding claims, characterized in that the pilot-operated valve (7) is stably associated with the bottom of the enclosure (21) of the filter (1) and its flow control element (7a, 7b) is provided with manual actuation means.

Inventors: BARACCHI PAOLO, CROVETTI CLAUDIO, TALLANO SERGIO, BARACCHI, PAOLO, CROVETTI, CLAUDIO, TALLANO, SERGIO
Applicants: BARACCHI PAOLO, CROVETTI CLAUDIO, SOGEFI FILTRATION S P A, TALLANO SERGIO, BARACCHI, PAOLO, CROVETTI, CLAUDIO, SOGEFI FILTRATION S.P.A., TALLANO, SERGIO
Application year: 2001
Main classification: F02M37
IPC codes: B01D29, B01D36, F02M37