EP2609310B1 - Method and device for cleaning of coked cavities, in particular for intake passages and valves in an internal combustion engine - Google Patents

Description

The present invention relates to a method and a device for cleaning coked cavities, in particular intake passages and valves of an internal combustion engine.

In internal combustion engines, such as gasoline and diesel engines impurities often occur in the intake ports and on the intake valves, which are caused in particular by low-quality fuels and / or unfavorable operation of the engines. The impurities are mainly hard and soft as well as greasy carbon deposits, which interfere with engine growth more and more with increasing growth, because when opening the intake valves the required inlet cross sections are not reached anymore.

If nothing is done against such deposits, massive faults in the inlet valves can occur, which means that the entire cylinder head of an engine has to be replaced.

The invention has for its object to provide a method and apparatus for cleaning coked cavities, in particular of intake ports of an internal combustion engine, which allows easy handling and effective removal of impurities and deposits even in hard to reach places.

This object is achieved by the method according to claim 1 and the device according to claim 8. Advantageous developments and refinements of the invention are described in the respective subclaims.

According to the invention, it is thus provided that the method for cleaning cavities, in particular inlet channels, comprises the following steps: introducing an alkaline liquid into a cavity to be cleaned, heating the alkaline liquid, and Aspirating the alkaline liquid with the contaminants contained therein from the cavity, wherein the alkaline liquid in particular has a pH of 7 to 14.

In a first embodiment of the invention, it is provided that a liquor in solid form and a solvent are mixed together and introduced into the cavity to be cleaned, so that the alkaline liquid is formed in the cavity to be cleaned by dissolving the liquor in the solvent with evolution of heat. Here, the cleaning effect of the alkaline liquid is significantly increased by the exothermic reaction, since the resulting heat can be used almost completely for heating the alkaline liquid and the impurities to be removed. The dissolved dirt particles are extracted by means of a pump.

In another embodiment of the invention it is provided that the alkaline liquid is heated prior to introduction, and the heated alkaline liquid is injected into the cavity, wherein the alkaline liquid is sucked with the dirt constituents contained therein from the cavity, while still alkaline liquid in the cavity is injected so that the cavity is continuously rinsed with alkaline liquid.

In order to build up a continuous rinse cycle, it is advantageous if the alkaline liquid with the dirt constituents contained therein is sucked out of the cavity and then filtered to remove the dirt constituents contained therein, and the filtered alkaline liquid is subsequently heated and injected back into the cavity , As a result, the consumption of cleaning fluid can be kept low without compromising the effectiveness of the cleaning process.

In order to mechanically aid the chemical cleaning action, it is provided that the alkaline liquid is injected under pressure against the walls and the bottom of the cavity.

It is also expedient to dry the cavity by means of compressed air after completion of the suction of the alkaline liquid.

Further, according to the invention, the device for cleaning cavities, in particular inlet channels, comprises a first probe which at its front end is provided with one or more nozzles for injecting a heated alkaline liquid into a cavity to be cleaned and which is connected at its other end to the pressure side of a pump, the suction side of heated alkaline liquid can be supplied, and a second probe for sucking the alkaline liquid with the dirt constituents contained therein from the cavity. With the device according to the invention, the alkaline liquid can be effectively bring even in hard to reach areas of cavities, where they can then fully develop their cleaning effect.

In order to build up a continuous rinse cycle, it is advantageous if the second probe is connected to the suction side of the pump via a filter for removing contaminants from the alkaline liquid. The two probes thus form with the pump and the filter an open system, which is closed over the cavity to be cleaned to a circuit for the alkaline liquid.

Conveniently, the outlet side of the filter is connected to the suction side of the pump via a connecting line to which a heater for heating a liquid flowing through is arranged. A heating of the alkaline liquid in the pressure side is possible.

In an advantageous embodiment of the device according to the invention it is provided that the first probe is a closed at its front end thin tube, in the peripheral wall a plurality of radially directed nozzles are provided. The nozzles can be arranged on a line parallel to the axis of the tube.

But it is also possible that the first probe have at least two nozzles for injecting the alkaline liquid into the cavity to be cleaned, which inject the alkaline liquid in different directions. In this case, the nozzles can be arranged on one or more helix (s) or on one or more circumferential circle (s).

Furthermore, it is expedient if at least one nozzle is provided in the region of the closed front end through which the alkaline liquid can be sprayed essentially in the axial direction of the tube of the probe.

• Figur 1 eine vereinfachte schematische Schnittdarstellung eines Einlasskanals eines Verbrennungsmotors, beispielsweise eines Dieselmotors;
• Figur 2 eine vereinfachte schematische Blockdarstellung einer erfindungsgemäßen Vorrichtung zur Reinigung von Hohlräumen, insbesondere zur Einlasskanal- und Ventilreinigung bei Verbrennungsmotoren;
• Figur 3 vereinfachte schematische Darstellungen verschiedener Ausführungsformen einer ersten Sonde zum Einspritzen einer alkalischen Flüssigkeit in einen zu reinigenden Hohlraum;
• Figur 4 eine vereinfachte schematische Blockdarstellung einer erfindungsgemäßen Vorrichtung gemäß einer vorteilhaften Weiterbildung;
• Figur 5 eine vereinfachte schematische Blockdarstellung der erfindungsgemäßen Vorrichtung nach Figur 4 mit zum Vorheizen kurzgeschlossenem Kreislauf; und
• Figur 6 eine vereinfachte schematische Darstellung einer Abdeckvorrichtung für die Öffnung eines zu reinigenden Hohlraums.

The invention will be explained in more detail below with reference to the drawing. Show it:

• FIG. 1 a simplified schematic sectional view of an intake passage of an internal combustion engine, such as a diesel engine;
• FIG. 2 a simplified schematic block diagram of a device according to the invention for the cleaning of cavities, in particular for the intake passage and valve cleaning in internal combustion engines;
• FIG. 3 simplified schematic representations of various embodiments of a first probe for injecting an alkaline liquid into a cavity to be cleaned;
• FIG. 4 a simplified schematic block diagram of a device according to the invention according to an advantageous embodiment;
• FIG. 5 a simplified schematic block diagram of the device according to the invention FIG. 4 with circuit shorted to preheat; and
• FIG. 6 a simplified schematic representation of a covering device for the opening of a cavity to be cleaned.

In the various figures of the drawing, corresponding components are provided with the same reference numerals.

FIG. 1 is an example of a cavity to be cleaned, namely an intake passage 10 in a cylinder head 11 of an internal combustion engine, such as a diesel engine 12, which is mounted in a conventional manner on a corresponding cylinder block 13. A in an unspecified cylinder opening in the cylinder block 13 outlet opening 14 of the intake passage 10 is conventionally closed by an intake valve 15 which is guided by a corresponding valve guide 16 in the cylinder head 11 to release and close the opening 14 of the intake passage in accordance with engine control.

The intake ports 10 and the intake valves 15 of diesel engines coke very much. Particularly affected are so-called swirl channels (not shown in detail), which are used in modern diesel engines with four valves per cylinder to impart a twist to the cylinder to be supplied gas mixture, which should lead to improved mixing of air and injected fuel. The deposits in the inlet channels 10 and the inlet valves 15 are in particular soft, greasy carbon deposits.

According to a first embodiment of the present invention, the cleaning of the inlet channels 10 and the inlet valves 15 is carried out by exposing the inlet-side openings 17 of the inlet channels 10 in the cylinder head 11 in the inlet channel 10, an alkaline liquid is either previously heated or in the Essentially heated after insertion. In this case, it is particularly expedient if, for heating the alkaline liquid, the heat of solution is utilized when dissolving a lye in a corresponding solvent.

It is particularly advantageous if the liquor, for example potassium hydroxide or sodium hydroxide, is introduced into the inlet channel 10 in solid form, as indicated by the arrow L in FIG FIG. 1 indicated to subsequently or partially also simultaneously supply a solvent, as indicated by the arrow F, so that the solution of the liquor is carried out in the solvent in the inlet channel 10, so that the cleaning effect of the liquor is optimally supported by the dissolution developing heat , The solvent used may be any suitable solvent, such as water or alcohol. However, particularly good cleaning results are achieved when hydrogen peroxide is used as the solvent. The mixing ratio of lye (in solid form) and solvent is chosen so that the resulting alkaline liquid has a pH of 7 to 14, in particular more than 12.

After a sufficient exposure time, during which the hard and / or soft, greasy carbon deposits are dissolved in the alkaline liquid and thus removed from the walls of the inlet channel 10 and the injection valve 15, the alkaline liquid together with the dirt constituents contained therein from the inlet channel 10th sucked off by means of a suction probe, not shown.

Subsequently, a rinsing of the inlet channel 10 with water or alcohol can then take place in order finally to dry it with compressed air before re-assembling the diesel engine after cleaning the inlet channels 10 and the inlet valves 15.

The described embodiment can be slightly modified by the fact that the mixing of liquor in solid form and solvent not only takes place in the inlet channel 10, but before, with the filling of the liquor / solvent mixture in the inlet channel 10 immediately follows the blending, so that the dissolution of the liquor in the solvent takes place only when the mixture of liquor and solvent is already in the inlet duct 10.

As in FIG. 2 1, a device 21 according to the invention for cleaning cavities, in particular intake passages 10 of an internal combustion engine, for example a diesel engine 12, comprises a first probe 21 and a second probe 22. The first probe 21 is provided at its front end with one or more nozzle (s). 23 for injecting an alkaline liquid into a cavity to be cleaned and connected at its other end to the pressure side 24 of a pump 25, the suction side 26 of a filter 27 via a connecting line 28, which is associated with a heater 29, heated alkaline liquid can be supplied , The second probe 22 is connected to an inlet side of the filter 27 so as to be connected to the suction side 26 of the pump 25 via the filter 27 serving to remove debris from the alkaline liquid and the connection pipe 28. The sucked by the pump 25 via the connecting line 28 from the filter 27 liquid is heated by the connecting line 28 associated heater 29 to a desired temperature. The heater may also be arranged in a manner not shown on the pressure side of the pump 25.

To mechanically assist the chemical cleaning action of the alkaline liquid, the first probe 21 is designed as a thin tube closed at its front end, in the circumferential wall of which a plurality of radially directed nozzles 23 are provided, as is particularly apparent in FIG FIG. 3 is shown. Taking into account the pressure that can be generated by the pump 25, the number and the diameter of the nozzles 23 are designed so that the individual jets emerging from the nozzles 23 are so strong that they can cause a mechanical detachment of the carbon deposits to be removed.

As in FIG. 3 (b) In addition to the nozzles 23 arranged on a line parallel to the axis A of the pipe, one or more additional nozzles 23 'can be provided, through which the alkaline liquid, as indicated in the drawing, in the axial direction or at least with a substantial proportion can be injected in the axial direction.

According to another embodiment, the nozzles 23 may also be mounted on one or more helix (s) (SL in FIG FIG. 3 (d) ) or on one or more circumference circle (s) ( FIG. 3 (c) ) can be arranged. The individual nozzles 23 may be circumferentially distributed uniformly or unevenly.

To clean an inlet duct 10 and an inlet valve 15 of a diesel engine by means of the described device, first the second probe 22, which is provided for sucking the alkaline liquid from the inlet channel 10, immersed in a reservoir 30 with alkaline cleaning liquid, after which the pump 25 is turned on Thus, the liquid is sucked from the reservoir 30 through the second probe 22 first in the filter 27 and further via the connecting line 28 and finally, after the air is removed from the system, alkaline liquid through the nozzles 23 in the first probe 21 in the inlet duct 10 sprays. Once the system of second probe 22, filter 27, connecting line 28, pump 25 and first probe 21 is filled with alkaline liquid and a suitable amount of alkaline liquid has accumulated in the inlet channel 10, the second probe 22 is removed from the reservoir 30 and also inserted into the inlet channel 10, in order to remove the alkaline liquid contained therein together with the dirt components contained therein, ie mechanically and / or chemically detached dirt constituents from it. The cleaning liquid is then cleaned in the filter 27 and fed through the connecting line 28 is heated by the heater 29 back to the desired temperature and then sprayed or sprayed by the pump 25 again under pressure into the inlet channel 10, wherein the individual liquid jets impinge on the walls of the inlet channel 10 itself and the surface of the inlet valve 15.

In this case, as in the first embodiment, it must be ensured that the inlet valves 15 of the inlet channels 10 to be cleaned are reliably closed. After then the inlet channel 10, as described above, filled with a corresponding amount of alkaline cleaning liquid and the second probe 22 is converted from the reservoir 30 into the inlet channel 10, a rinsing circuit is constructed in which the continuously aspirated cleaner (alkaline cleaning liquid) after treatment in the filter 27 and a renewed heating by the heater 29 is continuously fed back to the inlet channel 10. The continuous supply of the alkaline cleaning liquid under pressure by means of the first probe 21 provides, as mentioned above, the additional mechanical washing action.

Here, as in the first Ausführüngsbeispiel the cleaning can be completed by rinsing with water or alcohol and then drying with compressed air.

Tests on diesel engines have shown that with relatively short, only slightly curved inlet ducts, in which the contamination is significantly lower compared to the so-called swirl ducts, very good cleaning effects can already be achieved with a straight probe. In the case of so-called swirl ducts, that is to say for relatively long, curved inlet ducts with a lateral inlet opening for swirl generation, there are usually heavy soiling, especially in the region of the inlet valve. Here, a probe has proved to be useful, which sprays in several directions, in particular in several radial and axial directions, so that all points of the duct walls and the inlet valve can be achieved.

The invention thus provides a simple and reliable cleaning method for cleaning cavities, particularly coked cavities, such as the intake ports of an internal combustion engine, such as a diesel engine, with which its life can be significantly extended in a timely manner in a cost effective manner.

In the FIG. 4 shown inventive device for cleaning cavities, in particular of intake ports 10 of an internal combustion engine, such as a diesel engine 12 includes, as the above with reference to FIG. 2 explained device, a first probe 21 and a second probe 22. The first probe 21, which has one or more nozzles 23 as described above at its front end, with its other end via a heater 29 to the pressure side 24 of a first pump 25 connected, the suction side 26 is connected via a corresponding intake 31 with a reservoir 30 in conjunction. The second probe 22, so the suction probe is connected via a filter 27 to the suction side 36 of a second pump 35, the pressure side 34 is connected via a return line 32 to the reservoir 30 in combination.

The basis of FIG. 4 Thus, instead of a single pump, the cleaning device shown has two pumps, namely the first pump 25 serving as a pressure pump for injecting the alkaline fluid into the cavity to be cleaned, and the second pump 35 serving as a suction pump for aspirating alkaline fluid and contaminants from the cavity Drain or the pressure side 34 of the second pump 35 delivers the extracted and filtered from the cavity liquid via the return line 32 back into the reservoir 30, from which then via the suction line 31 alkaline liquid of the inlet or suction side 26 of the first pump is supplied. The liquid circuit is thus open in the region of the cavity to be cleaned and in the region of the reservoir 30.

In order to prevent splashing of the alkaline liquid for reasons of safety at work, the suction line 31 and the return line 32 via a corresponding, not shown adapter cover, which is screwed onto the inlet and outlet of the reservoir 30, tightly inserted into this.

In order to be able to cover the inlet opening of the cavity to be cleaned, in particular of the inlet channel 10 to be cleaned, in order to prevent splashing of the liquid injected under pressure into the cavity into the surroundings, one is used as an adapter plate 40 trained cover provided, which can be screwed in a manner not shown, for example by means of screws on the cylinder head 11.

The adapter plate 40 has two openings 41, through which the two probes 21, 22 can be passed substantially tight. The through holes 41 may be provided with either the alkaline liquid resistant seals made of artificial or natural rubber or the like. However, it is also possible to produce the adapter plate 40 from such a sealing material and to secure it to the cylinder head 11 with the aid of a metallic fastening frame.

Since, in particular in the region of the cavity to be cleaned, it can happen that more cleaning liquid is supplied than is sucked off, an overflow 42 is expediently provided, the outlet side of which can be connected to a collecting vessel (not shown).

The adapter plate 40, which in FIG. 6 is only shown to cover the opening of a single inlet channel 10, but can also be designed so that all lying in a line or in a plane valve inlet ducts are covered so that can be significantly reduced when cleaning the inlet ducts in the workshop of assembly work.

Before actually cleaning an intake passage 10 and an intake valve 15 of an internal combustion engine with the aid of FIG. 4 1, the liquid circuit is initially short-circuited in that the first probe 21, that is to say the probe for injecting liquid into the cavity, is introduced into the storage container 30 instead of the return line 32. Now sucked from the reservoir 30 alkaline liquid through the heater 29, which is arranged downstream of the first pump 25, heated and conveyed back into the reservoir 30. This process can be repeated until the alkaline cleaning liquid in the reservoir 30 has reached a desired temperature.

This operation is also with the basis of FIG. 2 described cleaning device possible.

Subsequently, after switching off the pump 25, the first probe 21, so the pressure probe for injecting the alkaline cleaning liquid is introduced into the cavity to be cleaned in this, this advantageously takes place through the adapter plate 40, as shown in FIG FIG. 6 is shown. Thereafter, the cycle is closed by means of the second probe 22 serving as a suction probe, the filter 27, the pump 35 and the return line 32. In this case, the second probe 22, which extends through the corresponding opening 41 of the adapter plate 40, immersed in the cavity to be cleaned, while the return line 32 is guided into the reservoir 30.

Now, first, the first pump 25 is turned on, so that alkaline cleaning liquid is injected into the inlet channel 11. As soon as a sufficient amount of alkaline cleaning liquid is in the inlet channel after a predetermined time, the second pump 35 is turned on to suck off liquid and dirt. The delivery rate of the two pumps should be substantially the same in order to maintain a constant liquid level in the inlet channel 10 during cleaning.

Subsequently, the cleaning of the inlet channel 10 and the inlet valve 15 is carried out in the same manner as described above, only with the difference that the filtered through the filter 27 cleaning liquid is returned to the reservoir 30, before being returned from the pressure pump 25 via the heater 29 in the inlet channel is injected.

Should it happen that the capacity of the first pump, so the pressure pump, but is greater than the suction of the second pump, so excess liquid can be safely collected through the overflow line 42 into a corresponding receptacle.

The use of two pumps, that is, a suction pump and a pressure pump for supplying cleaning fluid to the cavity to be cleaned has the advantage that the injection and suction of alkaline cleaning fluid can be controlled independently. Furthermore, not only the cleaning efficiency can be increased in this way, since the cleaning fluid is not consumed so quickly, but it can also improve the reliability in the workshop significantly although an open fluid circuit is used, since both the probes can be inserted tightly into the cavity to be cleaned by means of the adapter plate 40, and the suction and return lines are tightly inserted into the reservoir.

Claims (16)

1. A method for cleaning coked cavities, in particular inlet channels (10) and valves (15) of an internal combustion engine (12), having the following steps:

   - introduction of an alkaline liquid into a cavity to be cleaned,

   - heating of the alkaline liquid, and

   - extraction by suction of the alkaline liquid with the dirt particles contained therein from the cavity.
2. The method as claimed in claim 1, characterized in that a base in solid form and a solvent are mixed with one another and are introduced into the cavity to be cleaned, with the result that the alkaline liquid which, in particular, has a pH value of more than 12 is formed in the cavity to be cleaned by dissolving of the base in the solvent with the development of heat.
3. The method as claimed in claim 1, characterized in that

   - the alkaline liquid which, in particular, has a pH value of more than 12 is heated before being introduced, and

   - the heated alkaline liquid is injected into the cavity.
4. The method as claimed in claim 3, characterized in that the alkaline liquid with the dirt particles contained therein is extracted by suction from the cavity, while alkaline liquid continues to be injected into the cavity, with the result that the cavity is flushed continuously with alkaline liquid.
5. The method as claimed in claim 3 or 4, characterized in that

   - the alkaline liquid with the dirt particles contained therein is extracted by suction from the cavity and is subsequently filtered, in order to remove the dirt particles contained therein, and

   - the filtered alkaline liquid is heated and is subsequently injected into the cavity again.
6. The method as claimed in claim 3, 4 or 5, characterized in that the alkaline liquid is sprayed under pressure against the walls and the bottom of the cavity.
7. The method as claimed in one of the preceding claims, characterized in that, after the extraction by suction of the alkaline liquid has ended, the cavity is dried by means of compressed air.
8. A device for cleaning coked cavities, in particular inlet channels (10) and valves (15) of an internal combustion engine (12), having

   - a first probe (21) which is provided at its front end with one or more nozzles (23, 23') for injecting an alkaline liquid into a cavity to be cleaned and which is connected with its other end to the pressure side (24) of a pump (25), the suction side (26) of which can be fed heated alkaline liquid, and

   - a second probe (22) for extracting the alkaline liquid with the dirt particles contained therein by suction from the cavity.
9. The device as claimed in claim 8, characterized in that the second probe (22) is connected to the suction side (26) of the pump (25) via a filter (27) for removing dirt particles from the alkaline liquid.
10. The device as claimed in claim 9, characterized in that the outlet side of the filter (27) is connected via a connecting line (28) to the suction side (26) of the pump (25), the connecting line (28) or the pressure side of the pump (25) being assigned a heater (29) for heating a liquid which flows through.
11. The device as claimed in one of claims 8 to 10, characterized in that the first probe (21) is a thin tube which is closed at its front end and in the circumferential wall of which a plurality of radially directed nozzles (23) are provided.
12. The device as claimed in claim 11, characterized in that the nozzles (23) are arranged on a line which is parallel to the axis of the tube or on one or more helixes (SL) or on one or more circumferential circles, or in that at least one nozzle (23') is provided in the region of the closed front end, through which at least one nozzle (23') the alkaline liquid can be sprayed substantially in the axial direction (A) of the tube of the probe (21).
13. The device as claimed in one of claims 9 to 11, characterized in that the first probe (21) has at least two nozzles (23, 23') for injecting the alkaline liquid into the cavity to be cleaned, which nozzles (23, 23') spray the alkaline liquid in different directions.
14. The device as claimed in claim 8, characterized in that the second probe (22) is connected via a filter (27) for removing dirt particles from the alkaline liquid to the suction side (36) of a second pump (35) which serves as a suction pump and the outlet or pressure side of which is connected to a storage vessel (30).
15. The device as claimed in claim 14, characterized in that the suction side (26) of a pump (25) which serves as a pressure pump is connected via an intake line (28) to the storage vessel (30), the pressure side of the pump (25) or the intake line (28) being assigned a heater (29) for heating a liquid which flows through.
16. The device as claimed in one of the preceding claims, characterized in that, furthermore, a covering device (40) is provided for covering the opening of the cavity to be cleaned, which covering device (40) has two leadthroughs (41) for the first and second probes (21, 22) and is provided with an overflow line (42) which can be connected to a collecting vessel.

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