Method for manufacturing an electro-filter

Abstract

A method for manufacturing an electro-filter for separating a mixture of gas and oil drops including: at least one body including at least one oil/gas separation chamber, at least one emitter electrode, and at least one collector electrode made of an electrically-conductive plastic material. The manufacturing method includes at least the following steps: implementation of a first injection cycle having at least one step of injecting the collector electrode, implementation of an overmolding cycle having at least the following steps: displacement of the injected collector electrode into a second cavity of the same mold or into the cavity of another mold, overmolding at least the oil/gas separation chamber of the body at least on the collector electrode, with an electrically-insulating plastic material.

Claims

1. A method for manufacturing an electro-filter for separating a mixture of gas and oil drops originating from an internal combustion engine, said electro-filter comprising: at least one body including at least one oil/gas separation chamber; at least one emitter electrode; and at least one collector electrode made of an electrically-conductive plastic material, the manufacturing method comprising: implementation of a first injection cycle comprising injecting the at least one collector electrode with the electrically-conductive plastic material into a first cavity of a mold, implementation of an overmolding cycle comprising: displacing the at least one injected collector electrode into a second cavity of the same mold or into a cavity of another mold; and overmolding the at least one oil/gas separation chamber of the at least one body at least on the at least one injected collector electrode with an electrically-insulating plastic material.

2. The manufacturing method according to claim 1, wherein the overmolding cycle for forming a first electro-filter is carried out at the same time as the first cycle of injecting the at least one collector electrode for formation of a second electro-filter.

3. The manufacturing method according to claim 1, wherein the first injection cycle comprises injecting the at least one emitter electrode into a third cavity with an electrically-conductive plastic material.

4. The manufacturing method according to claim 3, further comprising removing the at least one injected emitter electrode from the mold or displacing the at least one injected emitter electrode into the second cavity of the mold.

5. The manufacturing method according to claim 4, wherein the at least the separation chamber is overmolded on the at least one emitter electrode and the at least one collector electrode in the second cavity of the mold.

6. The manufacturing method according to claim 1, further comprising implementing a second injection cycle simultaneously or subsequently or anteriorly to the first injection cycle or to the overmolding cycle.

7. The manufacturing method according to claim 1, further comprising implementing at least one assembly cycle implemented subsequently at least to the overmolding cycle.

8. The manufacturing method according to claim 7, wherein the assembly cycle comprises assembling the at least one emitter electrode with the overmolded body of the electro-filter.

Description

(1) The invention will be better understood, thanks to the description hereinafter, which relates to embodiments according to the present invention, given as non-limiting examples and explained with reference to the appended schematic drawings, in which identical reference numerals correspond to structurally and/or functionally identical or similar elements. The appended schematic figures are listed hereinbelow:

(2) FIG. 1 is a perspective view of the electro-filter according to the invention according to a first embodiment,

(3) FIG. 2 is a perspective view of the body of the electro-filter overmolded on the collector electrode (step b.2 of the manufacturing method) according to a variant of the first embodiment,

(4) FIG. 3 is a partial detail bottom view of the body of the electro-filter overmolded on the collector electrode according to the variant of the first embodiment,

(5) FIG. 4 is an exploded perspective view of the electro-filter according to the first embodiment,

(6) FIG. 5 is a perspective view of the emitter electrode and of the collector electrode made according to steps a.1 and a.2 of the manufacturing method according to the invention,

(7) FIG. 6 is a perspective view of a portion of the body of the electro-filter overmolded on the electrodes according to a second embodiment,

(8) FIG. 7 is a perspective view of the electro-filter according to a second embodiment,

(9) FIG. 8 illustrates a sectional view of the electro-filter according to the first embodiment,

(10) FIG. 9 illustrates an engine head cover forming at least partially the electro-filter according to the invention,

(11) FIG. 10 is a schematic view of the steps of the manufacturing method of the first embodiment,

(12) FIG. 11 is a schematic view of the steps of the manufacturing method of the variant of the first embodiment,

(13) FIG. 12 is a schematic view of the steps of the manufacturing method of the second embodiment.

(14) Regardless of the embodiment, the electro-filter 1 according to the invention is configured to separate a mixture of gas and oil drops originating from an internal combustion engine. The electro-filter 1 comprises a body 2 including at least one oil/gas separation chamber 3, an oil recovery chamber 4.

(15) Regardless of the embodiment, the separation chamber 3 and the recovery chamber 4 are made of an electrically-insulating plastic material.

(16) Furthermore, and regardless of the embodiment, the electro-filter 1 comprises at least one emitter electrode 8 positioned in the separation chamber 3 of the body 2, and at least one collector electrode 9 positioned in the separation chamber 3 of the body 2.

(17) Regardless of the embodiment, and as illustrated in FIG. 4, the emitter electrode 8 comprises a jumper 8a, a point 8c and a retaining member 8b configured to cooperate with a complementary retaining member 6b formed on a portion of the body 2 and more particularly on the connecting part 6 which will be detailed later on.

(18) Furthermore and regardless of the embodiment, the collector electrode 9 is in the form of an open box deprived of a front face and rear face as illustrated in FIGS. 4 and 5, so that the gas to treat passes inside the collector electrode and is ionized by the point-shaped emitter electrode. More particularly, the two plates 9a, 9b of the collector electrode 9 are connected to each other by a top face on which is formed a jumper 9c protruding from the top face and a bottom face opposite to the top face.

(19) Advantageously, a recess is formed on the top face and opening into the enclosure 9d of the collector electrode 9.

(20) Regardless of the embodiment, the collector electrode 9 is made of an electrically-conductive plastic material, for example a polyamide charged with carbon fibers.

(21) Regardless of the embodiment, the emitter electrode 8 is made of an electrically-conductive plastic material, for example a polyamide charged with carbon fibers.

(22) Regardless of the embodiment, the electro-filter 1 further comprises a gas inlet connecting part 6 intended to cooperate with a conduit conveying the gas to treat (not represented) and shown in FIGS. 1, 2, 4, 6 and 7. Preferably, the connecting part 6 is made of an electrically-insulating plastic material. The connecting part 6 comprises a gas inlet 6a intended to cooperate with a conduit. Furthermore and as shown in FIG. 4, the connecting part 3 comprises two branches 6c arranged on either side of the inlet 6a. One of the branches 6c is provided with a complementary retaining member 6b intended to cooperate with the retaining member 8b of the emitter electrode 8. Once assembled and overmolded, the branches 6c of the connecting part 6 are arranged in the separation chamber 3 as illustrated in FIG. 8. Advantageously, the two branches 6c of the connecting part 6 are placed inside the open parallelepiped forming the collector electrode in contact with the top face and the bottom face of the collector electrode 9, which allows avoiding the top face and the bottom face of the collector electrode 9 collecting the oil drops. Thus, the oil is collected only on the lateral plates 9a, 9b of the collector electrode 9, which allows controlling the oil collection location by making the collected oil run in the form of a film or trickle by the effect of gravity and the speed of the gas flow on the plates 9a, 9b. Thanks to the control of oil collection, it is easier to position the oil outlet orifice 7b.

(23) Regardless of the embodiment, the electro-filter 1 comprises a housing 5 intended to house a generator intended to be in connection with the emitter 8 and collector 9 electrodes. More particularly, the separation chamber 3 comprises a receiving element 3a, as shown in FIG. 4, shaped so as to receive the housing 5. The housing 5 comprises a cooperation portion 5b cooperating with the receiving element 3a of the separation chamber 3 and a circumferential retaining flange 5a intended to receive the generator (not represented). Preferably, the housing 5 is made of an electrically-insulating plastic material.

(24) Regardless of the embodiment, the electro-filter 1 further comprises a cap 7 comprising an oil return 7a or oil outlet conduit. The cap 7 is shaped so as to close the oil recovery chamber 4. The cap 7 comprises an outlet orifice 7b fluidly connecting the recovery chamber 4 with the oil return 7a as illustrated in FIG. 4.

(25) Regardless of the embodiment, at least the body 2 of the electro-filter 1 according to the invention forms a portion of the walls of a head cover 100 as illustrated in FIG. 9.

(26) The electro-filter 1 according to the invention may be made in various manners. The figures illustrate two possible embodiments but other non-illustrated embodiments are also possible.

(27) The first embodiment and the variant of the first embodiment will now be described according to the diagrams of FIGS. 10 and 11 and with reference to FIGS. 1 to 4.

(28) To manufacture the electro-filter 1 according to the first embodiment, a first injection cycle A is implemented during which a collector electrode 9 is injected into a first cavity of a mold according to an injection step a.1. In parallel (subsequently, anteriorly, or simultaneously), an emitter electrode 8 is injected into another mold or into a third cavity of the same mold according to an injection step a.2. Then, the emitter electrode 8 is removed from the mold in which it has been injected according to the removal step a.3 and in parallel (subsequently, anteriorly, or simultaneously), the collector electrode 9 is displaced into a second cavity of the mold according to a displacement step b.1. Afterwards, according to an overmolding cycle B, the separation chamber 3 and the recovery chamber 4 of the body 2 are overmolded in the second cavity of the mold and on the collector electrode 9 according to the overmolding step b.2.

(29) Alternatively to this first embodiment and as illustrated in FIGS. 2 and 3, the separation chamber 3, the recovery chamber 4, the housing 5, the connecting part 6 of the body 2 are overmolded in the second cavity of the mold and on the collector electrode 9 according to the overmolding step b.2.

(30) According to the first embodiment and according to a second injection cycle C, the housing 5 is obtained by a plastic injection step c.3 carried out in parallel (subsequently, anteriorly, or simultaneously) to the first injection cycle A or to the overmolding cycle B. Furthermore, the connecting part 3 is obtained by a plastic injection step c.2 carried out in parallel (subsequently, anteriorly, or simultaneously) to the first injection cycle A or to the overmolding cycle B. Furthermore, the cap 7 is obtained by a plastic injection step c.4 carried out in parallel (subsequently, anteriorly, or simultaneously) to the first injection cycle A or to the overmolding cycle B. The injection steps (c.2, c.3, c.4) may be carried out consecutively or simultaneously.

(31) Afterwards, according to the first embodiment, an assembly cycle D is implemented, in which are assembled by bonding or welding, or clipping, the housing 5 (step d.4), the connecting part 6 (step d.3), the cap 7 (step d.5) and the emitter electrode 8 (step d.1) on the overmolded body 2. The assembly steps (d.1, d.3, d.4, d.5) may be carried out consecutively or simultaneously.

(32) According to the variant of the first embodiment, after overmolding, an assembly cycle D is implemented, in which are assembled by bonding or welding, or clipping, the emitter electrode 8 (step d.1) and the cap 7 (step d.5), the cap 7 being obtained by a plastic injection step c.4 carried out in parallel (subsequently, anteriorly, or simultaneously) to the first injection cycle A or to the overmolding cycle B. The assembly steps (d.1, d.5) may be carried out consecutively or simultaneously.

(33) The second embodiment will now be described according to the diagram of FIG. 12 and with reference to FIGS. 5 to 7.

(34) To manufacture the electro-filter 1 according to the second embodiment, a first injection cycle A is implemented during which a collector electrode 9 is injected into a first cavity of a mold according to an injection step a.1. In parallel (subsequently, anteriorly, or simultaneously), an emitter electrode 8 is injected into a third cavity of the same mold according to an injection step a.2. Then, the collector electrode 9 is displaced into a second cavity of the mold according to a displacement step b.1 and the emitter electrode 8 is displaced into the second cavity of the mold according to a displacement step b.1bis. Afterwards, according to an overmolding cycle B, the separation chamber 3, the housing 5 and the connecting part 6 are overmolded in the second cavity of the mold and on the collector electrode 9 and the emitter electrode 8 according to the overmolding step b.2.

(35) According to the second embodiment, a second injection cycle C is implemented in which, the cap 7 is obtained by a plastic injection step c.4 in parallel (subsequently, anteriorly, or simultaneously) to the first injection cycle A or to the overmolding cycle B, and the recovery chamber 4 is obtained by a plastic injection step c.1 carried out in parallel (subsequently, anteriorly, or simultaneously) to the first injection cycle A or to the overmolding cycle B. The injection steps (c.1, c.4) may be carried out consecutively or simultaneously.

(36) Afterwards, an assembly cycle D is implemented, in which are assembled by bonding or welding, or clipping, the recovery chamber 4 (step d.2), the cap 7 (step d.5) on the overmolded body 2. The assembly steps (d.2, d.5) may be carried out consecutively or simultaneously.

(37) Of course, the invention is not limited to the embodiments described and shown in the appended figures. Modifications remain possible, in particular with regard to the constitution of the various elements or by substitution with technical equivalents, without departing from the scope of the invention.