HUT56922A - Piston provided with eddy-making unit for diesel-engines - Google Patents

Abstract

The invention relates to a piston with swirl-inducing device for Diesel engines, where a recess is machined in the upper part of the piston which is in communication with the engine's main combustion chamber when the piston is built-in. The essence of the invention lies in that said swirl-inducing device (4) comprises a heat storage insert (5) fixed in the piston's (1) recess (3) axially spaced from a bottom plate (6) of the recess (3) by way of a reduced heat transfer connection and provided with a series of gas turbulence inducing ducts (12) through which a space (14) of the recess (3) created by said axial spacing (7) below the heat storage insert (5) is in communication with a space, e.g. the main combustion chamber (13) above the heat storage insert (5).

Description

BACKGROUND OF THE INVENTION The present invention relates to a piston with a vortex generating unit for use in diesel engines.

It is well known that in the various combustion configurations of diesel engines, designers place great emphasis on creating and utilizing air vortices to improve atomization and combustion during compression and gas expansion.

For direct injection diesel engines, combustion71757-10147 / MJ ·· * · 9 9 · • 4 · · »*« • * · · · ₉ * «· ·« «, *» »_ _Μ

The space in the upper part of the piston is formed as a double spherical cavity of various shapes, e.g. (Such as the engines known in practice as HESSELMAN, MAN, JUNKERS, or SAURER). This combustion chamber communicates with the main combustion chamber formed in the cylinder space. Already at the suction stroke, the incoming air receives a swirling torque, which continues during compression. Examples include Jurek: Internal Combustion Engines. (Textbook Publisher, Budapest, 1955, pp. 565-573).

In practice, today, the practitioner regards the various versions of the above solutions as the most advanced.

Practical experience shows that diesel engines equipped with a piston with a known vortexing unit can still be barely improved in efficiency, economy and flue gas emissions by conventional means, which is inherently limited by the design itself.

It is an object of the present invention to overcome the above shortcomings, that is, to provide an improved vortexing unit for diesel engine pistons that significantly improves combustion process, operating economy, engine efficiency and flue gas emissions.

The present invention is based on the discovery that the object of the present invention can be achieved by improving the heat storage capacity of the insert by means of special insert-like elements of the piston vortex generator, and by improving the combustion process by extending the combustion process by special vortexing. ♦ ··· Λ .1. .:. :

-3a efficiency.

In order to accomplish this object, we have started from a piston with a known vortex generator, in which the piston is provided with a recess in its upper part which is connected to the main combustion chamber of the diesel engine when the piston is installed.

According to the present invention, the further development is that the vortex generator has a plate-like heat storage insert which is fixed in the piston recess by a heat transfer connection reduced axially from the bottom plate of the recess, and the insert is provided with a series of gas vortex passages.

Preferably, the insert is in the form of a circular disc having a circumferential groove partially accommodating the retaining ring along the periphery of the cylinder, and a portion of the retaining ring extending radially from the disc disposed in a recess in the recess of the piston. This results in a very simple and inexpensive design.

According to a further feature of the invention, the manufacture of the disc-like insert can be further simplified by forming the vortex passageways formed from the outer edge of the insert, preferably radial slots, which extend through the entire thickness of the insert, but at an angle to the face of the insert.

The invention will now be described in more detail with reference to the accompanying drawings, in which the examples according to the invention are illustrated with reference to the following embodiment. . In the drawing:

Figure 1 is a longitudinal sectional detail of a piston having a vortex-forming unit according to the invention;

Figure 2 is a top plan view of the insert of the vortex generator of Figure 1;

Figure 3 is a side view of the solution of Figure 2.

Figure 1 is a schematic longitudinal section showing only the top of the piston 1 of a diesel engine. The upper end surface 2 of the piston 1 has a slot-like recess 3, which in this case is a cylindrical bag bore.

According to the invention, the recess 3 of the piston 1 is provided with a special vortex forming unit 4, which according to the invention has a plate-like heat storage insert 5. This insert 5 is fixed in the recess 3 of the piston 1 at an axial distance 7 from the bottom plate 6. According to the invention, with respect to the fastening mode, a fastening connection is proposed which results in reduced heat transfer between the insert 5 and the piston connection body.

In the exemplary embodiment illustrated, the insert 5 is formed from a conventional material of the exhaust valves as a circular disk having a diameter D and a thickness B in Figures 2 and 3, respectively. The diameter D of the insert 5 is many times the thickness B and is selected to be inserted into the bore 3 of the recess 3 of the piston 1. 5 · · · · · · · · · · · · · · · · · · · · · · ·. : · .. ·· .. · meter.

In Figures 1 and 2, it can be clearly seen that the insert 5 is provided with a groove 9 extending along its cylindrical circumference 8, which is intended to receive a part of the fastening ring 10 known per se. The portion of the retaining ring 10 extending from the insert 5 sits in a radial groove 11 formed in the face of the recess 3. The insert 5 is thus secured in a manner known per se with the retaining ring 10 in the recess 3 of the piston 1.

According to the invention, the heat storage liner 5 is provided with a series of gas vortex passageways 12 which pass through one end of the main combustion chamber 13 in the region of the front surface 2 of the piston and at the other end in the recess 5 through the spacer space 14.

The gas vortex passageways 12 in the case shown are formed as radial slots, which, as shown in FIG. 2, are spaced evenly along the circumference, of varying lengths. The slots 12 can be made by a simple notch starting from the outer periphery 8 of the insert 5, but their direction is, as shown in Fig. 3, at an angle 17, in particular an acute angle, with the upper and lower faces 15 and 16 of the insert. This oblique design of the slot passages 12 achieves the desired vortexing effect in the space 14 and also in the space above the insert 5 by the reflux.

The retaining ring 10 is relatively light in relation to the weight of the insert 5 so as to ensure from the outset that relatively little heat is transferred from the insert 5 to the piston 1. Namely, one of the important functions of the insert 5 according to the invention is heat storage, for which it has the appropriate heat resistance and heat storage capacity.

The piston (1) provided with the vortex generator (4) according to the invention has the following advantages during engine operation:

During the operation of the engine, during compression of the air, the combustion air is forced through the vortex passages 12 of the heat reservoir 5 while being swirled in space 14. As the piston 1 continues to move upwardly, through the passages 12, the further compressed combustion air from the space 14 returns to the main combustion chamber 13 with further eddy torque.

Due to the heat of the heat storage insert 5, the combustion air heats up faster to the operating temperature. The combustion air thus swirled and held is effectively and uniformly mixed with the injected fuel and provides a more complete combustion process than is known in the art.

The advantageous effect of the heat storage pad 5 on the improvement of the combustion process does not, in view of the foregoing, require further explanation by the skilled person.

Our experiments with the illustrated exemplary embodiment of the present invention have shown that it can improve engine efficiency, reduce fuel consumption relatively, and significantly reduce fuel consumption.

-7 - capital is a harmful component in the exhaust gases, which is also of significant environmental importance.

Thus, according to the invention, a portion of the heat generated in the combustion process is consciously retained and stored in the insert 5, thereby significantly reducing the heat load on the engine cylinder and other structural parts.

In our experiments, it has also been surprisingly technical that the vortex generating unit 4 according to the invention softens the engine running, that is, eliminates the otherwise uncomfortable knocking of the diesel engine, especially at lower rpm and load ranges. This is due to the fact that in the main combustion chamber 13 there is no sudden and explosive combustion, but by flowing the mixture through the passages 12 to and from the space 14, the combustion process is slightly prolonged resulting in softer engine running and perfect combustion of more difficult to burn components. too.

Of course, the invention is not limited to the embodiment illustrated and described above, and many other variations thereof are possible within the scope of the claimed application. Thus, for example, the heat storage insert 5 does not have to be a circular disk, which can be justified at most by its very simple manufacture and assembly. Further, the vortex-forming passageways 12 may have non-radial directions and may even be formed as other suitable vortex-forming piercings instead of gaps. The recess 3 may also be of any other shape. The reduced heat transfer fastening mode may also be carried out between the heat reservoir insert 5 and the piston by any other means, for example, by the use of spot-on insulating and heat-resistant fasteners. Moreover, an embodiment of the embodiment of FIG. 1 is provided in which a flattened and only occasionally resilient member is provided between the peripheral surface of the retaining ring 10 and the insert 5 or the end face of the groove 11 to center the insert 5 in the recess 3. and further reduce heat transfer.

Finally, it is noted that during operation, the heat storage pad 5 is in glow, thereby immediately gasifying the dripping fuel droplets. In the compression stroke, the air passes through the passages 12, but during the expansion of the stroke, the created gas swirling has the opposite meaning.

Claims (3)

PATENT CLAIMS) A piston with a vortex generator for diesel engines having a recess in the upper part of the piston, which when in connection with the piston, is connected to the main combustion chamber of the engine, characterized in that the vortex generator (4) has a heat storage insert (5). ) is fixed axially from the bottom plate (6) of the recess (3) via a reduced heat transfer connection, and the heat storage insert (5) is provided with a series of vortexing passages (12) through which the recess (3) During this process, the space (14) formed by the axial distance (7) travels with the space above the heat storage liner (5), such as the combustion chamber (13). A piston with a vortex-forming unit according to claim 1, characterized in that the heat-storage insert (5) of the vortex-forming unit (4) is formed as a circular disk having a locking ring receiving groove (9) along its cylindrical outer periphery (8), and the portion of the retaining ring (10) projecting from the heat storage insert (5) sits in the radial groove (11) of the recess (3) of the piston (1). Piston with vortex forming unit according to claim 1 or 2, characterized in that the vortex forming passages (12) starting from the outer periphery (8) of the heat storage liner (5), preferably radially, extend over the entire thickness of the liner (5). They (B) are formed as through slots, the direction of which defines an acute angle (17) with the face (15, 16) of the insert (5).