DE102018122249A1 - Internal combustion engine - Google Patents

Abstract

The invention relates to an internal combustion engine having at least one piston (1) which can be moved back and forth in a cylinder and has a piston cooling space (6) for accommodating means for cooling and lubrication, the piston (1) being connected to a small connecting rod bearing (3 ) arranged piston pin (2) is pivotally connected to a connecting rod (4) and between the piston cooling chamber (6) and a connecting rod (4) oriented surface (FF) of the piston (1) at least one connecting channel (10) is provided and in the connecting rod (4) an inlet channel (11) to the small connecting rod bearing (3) is arranged. The object of the invention is to provide an internal combustion engine which achieves adequate cooling of the piston crown (7), as well as lubrication and cooling of the small connecting rod bearing (3). This object is achieved in that substantially between the connecting channel (10) and inlet channel (11) between the connecting rod (4) and piston (1) a collecting element (13) for collecting means for cooling and lubrication is arranged.

Description

The invention relates to an internal combustion engine having at least one reciprocable in a cylinder piston having a piston cooling chamber for receiving means for cooling and lubrication, wherein the piston is pivotally connected via a piston rod arranged in a small pivot bearing with a connecting rod and between the piston cooling chamber and a connecting rod oriented to the connecting rod surface of the piston is provided at least one connecting channel and in the connecting rod an inlet channel to the small connecting rod bearing is arranged.

Due to the high thermal and mechanical loads, it is necessary to cool and lubricate the connecting rod bearing, which is usually used oil. In order to supply the area of the small connecting rod bearing with oil, it is known in the prior art to provide a connecting channel in the form of a bore from an oil cooling channel through the piston to a connecting rod-oriented surface of the piston and an inlet channel in the connecting rod to the small connecting rod bearing also provided in the form of a bore. Depending on the speed of rotation, these holes move the oil in the direction of the small connecting rod bearing. However, it is unpredictable how much oil can actually get to the small connecting rod bearing, since the oil flows past the holes during the movement of the connecting rod and is lost.

Due to high ignition pressures and high surface pressures in the small connecting rod bearing, the bearing shell of the small connecting rod bearing is heavily loaded. In the case of poor oil supply, lack of lubrication and / or cooling can therefore lead to damages which entail frequent maintenance or replacement of the corresponding components with associated downtimes.

The US 3,992,980 A shows a piston which is supplied via holes in the connecting rod from a crankshaft ago with oil. Through another bore from the small connecting rod bearing to the outer surface of the connecting rod, the oil enters the interior of the piston. To better hold the oil in the piston for lubrication inside sealing lips are provided, which are arranged in the piston to the connecting rod out. By guiding the oil through the connecting rod lubrication of the piston pin is indeed possible, but the cooling of the piston crown is complicated by this construction. A targeted cooling of the piston crown is therefore not possible.

The object of the invention is to provide an internal combustion engine which avoids these disadvantages and in which the piston, in particular the piston crown can be sufficiently cooled and in which the lubrication and cooling of the small connecting rod bearing is ensured.

This object is achieved by an internal combustion engine mentioned above, according to the invention, that a collecting element for collecting means for cooling and lubrication is arranged substantially between the connecting channel and inlet channel between the connecting rod and piston. This makes it possible with the means for cooling and lubrication - e.g. Oil - which flows from the piston cooling chamber to the small connecting rod bearing, nevertheless sufficiently cools and lubricates the connecting rod bearing, since less cooling and lubrication means are lost for this purpose and flow back into the crankcase or to the oil sump.

In order to ensure easy pivoting between the piston and the connecting rod, it is advantageous if the collecting element brush elements and / or lamellae. The resistance and friction caused by the collecting element between connecting rod and piston is low due to the brush elements and negligible for the heat input.

In order to provide a buffer for the means for cooling and lubrication, it is advantageous if the collecting element essentially defines an inner collecting volume with brush elements and / of the lamellae, connecting rod and piston, wherein the brush elements and / or lamellae are preferably arranged annularly around one of the channels ,

In order to maintain the tightness of the collecting element and still the required mobility, it is advantageous if ends of the brush elements and / or the lamellae are directed to the outer surface of the connecting rod and preferably touch the outer surface.

A particularly simple embodiment results when the collecting element is fastened with a base element on the piston rod-oriented surface of the piston.

In order to obtain a simple and easily produced shape, it is provided in a preferred embodiment that the collecting element has a base area which is elliptical, preferably circular.

The maximum effect of the collecting element can be achieved if the collecting element encloses / covers the inlet channel when the connecting rod is pivoted, and / or if the collecting element encloses an angle of 25 ° to 30 ° in the circumferential direction.

In order to obtain the largest possible volume within the collecting element, it is advantageous if the collecting element has a width in the direction of an axis of rotation of the piston pin, which substantially corresponds to a Pleuelaugenbreite the connecting rod.

A particularly preferred embodiment provides that the collecting element is arranged above a rotational axis of the piston pin.

• 1 einen Kolben einer erfindungsgemäßen Brennkraftmaschine in einem Schnitt gemäß der Linie I-I der 2;
• 2 den Kolben in einer Ansicht von einer Unterseite;
• 3 das Detail III aus 1;
• 4 ein Auffangelement in einem Grundriss;
• 5 den Kolben in einem Schnitt gemäß der Linie V-V der 2; und
• 6 ein Auffangelement in einer perspektivischen Darstellung mit angedeutetem Verbindungskanal 10.

In the following, the invention will be explained in more detail with reference to a non-limiting embodiment, which is illustrated in the figures. Show:

• 1 a piston of an internal combustion engine according to the invention in a section along the line II of 2 ;
• 2 the piston in a view from a bottom;
• 3 the detail III off 1 ;
• 4 a catch element in a floor plan;
• 5 the piston in a section along the line VV the 2 ; and
• 6 a collecting element in a perspective view with indicated connecting channel 10 ,

The same elements are each provided with the same reference numerals in the figures for reasons of clarity. The 1 shows a piston 1 an internal combustion engine according to the invention in a first section along the line II in FIG 2 , Here is the piston 1 about one in appropriate shots 17 (please refer 2 ) of the piston 1 mounted piston pin 2 with a connecting rod 4 connected, the piston pin 2 rotatable and pivotable in a connecting rod bearing 3 a small connecting rod eye 30 the connecting rod 4 is arranged. Towards a combustion chamber of the internal combustion engine not shown in detail, the piston 1 a piston bottom 5 on, with this on one of the connecting rod 4 opposite side of the piston 1 is executed.

The interior of the piston 1 is for weight reasons and for receiving connecting rod 4 and piston pin 2 or designed to allow their pivoting movement as far as possible hollow. On the piston bottom 5 opposite side of the piston 1 , ie substantially on its inside, results in particular in an area between the recordings 17 for the piston pin 2 in a direction parallel to a rotation axis DD of the piston pin 2 an inner surface of the piston 1 , This inner surface is essentially one to the connecting rod 4 , in particular to the small connecting rod oriented surface FF dar. Between the inner surface of the piston 1 or to the connecting rod 4 oriented area FF and the outer surface or an outer surface AA the connecting rod 4 in the area of the small connecting rod eye 30 results in a distance is provided so that a free moving - in particular pivoting - the connecting rod 4 around the piston pin 2 is possible without causing a contact of the outer surface AA the connecting rod 4 with the area FF comes.

On one of the connecting rod 4 facing side - in other words: on a side facing away from the combustion chamber - has the piston 1 Furthermore, a piston refrigerator 6 on, which is substantially annular around a stroke axis EE of the piston 1 is running running, which stroke axis EE is to be considered substantially coinciding with a piston longitudinal axis. This piston refrigerator 6 is intended to contain means for cooling and lubrication, usually oil. In the following, the term oil is predominantly used, thereby including the use of other fluids that allow cooling and lubrication.

The supply of the oil via a arranged in the oil pan or the crankcase oil spray nozzle 12 , The piston refrigerator 6 is used in particular for cooling a piston crown 7 that the raised edge of the piston crown running on the side of the combustion chamber 5 referred to, in the lateral area of the piston 1 into the piston skirt, in the grooves 7 ' are executed for the piston rings (not shown).

To the oil, or the means for cooling and lubrication in the annular in the piston 1 arranged piston cooling chamber 6 restrain and prevent escape towards the oil pan, so that a longer residence time and thus cooling effect in the thermally highly loaded area of the piston crown 7 results, is a closure element for the piston cooling chamber 6 in the form of a sheet 8th provided that the piston refrigerator 6 on the bottom of the piston 5 opposite side at least partially closes.

The oil passes through openings and pipes 9 the piston refrigerator 6 fed. The opening of the oil spray nozzle 12 is in the illustrated embodiment in alignment with the tube 9 arranged so that the loading of the piston cooling chamber 6 is made possible with oil.

In addition to the cooling function, the oil is also used to connect the connecting rod 4 in the area of the small connecting rod eye 30 to lubricate and cool. These are one or more connection channels 10 between the piston refrigerator 6 and the to the connecting rod 4 oriented area FF of the piston 1 - so its inner surface - executed. Such a connection channel 10 is among other things the 1 and 3 refer to. The connection channel 10 takes its exit or has its entrance opening 10 ' in one of the stroke axis EE of the piston 1 facing, ie the Hubachsenseitigen inner surface of the piston cooling chamber 6 , The mouth or exit opening 10 " of the connection channel 10 is located in the inner surface or to the connecting rod 4 oriented surface FF of the piston 1 , in particular at an operating position of the piston 1 with regard to the entrance opening 10 ' Geodetic lower position. The connection channel 10 , which is designed in particular as a bore, is thus at an acute angle which is smaller than 90 °, against the stroke axis EE of the piston 1 inclined. The exit opening 10 " is located on the inner surface or to the connecting rod 4 oriented area FF of the piston 1 preferably in an area that is in a direction along the axis of rotation DD of the piston pin 2 between shots 17 for the piston pin 2 is positioned. About this connection channel 10 can the oil with it from the piston refrigerator 6 the connecting rod 4 be fed, which is thereby cooled and lubricated.

Additionally is in the connecting rod 4 in the area of the small connecting rod eye 30 at least one inlet channel 11 executed, the connection between the outer surface or outer surface AA the connecting rod 4 in the area of the small connecting rod eye 30 and the small rod bearing 3 manufactures. Preferably, the inlet channel runs 11 with regard to the axis of rotation DD of the piston pin 2 in the radial direction. In particular, the opening of the inlet channel 11 (Feed exit port 11 " ) on the side of the connecting rod bearing 3 arranged in an operating position of the internal combustion engine at a geodetically lower position than the opening on the outer surface AA the connecting rod 4 (Feed inlet opening 11 ' ). The inlet inlet opening 11 ' on the outer surface of the connecting rod 4 is preferably arranged at a position which, when the internal combustion engine is used as intended, always lies in a region between the axis of rotation DD of the piston pin 2 and the piston crown 5 located. Due to the pivoting of the connecting rod about the axis of rotation DD of the piston pin 2 During operation of the internal combustion engine, the inlet inlet opening moves 11 ' relative to the piston 1 on a circular segment of a circular path around the axis of rotation DD of the piston pin 2 ,

The oil flowing through the connecting channel 10 from the piston refrigerator 6 to the connecting rod 4 is passed, can flow through said arrangement to the connecting rod bearing 3 and there for lubrication and - especially in highly loaded engines - provide cooling.

So the oil comes from the piston nozzle 12 over the pipe 9 , the piston refrigerator 6 , through the connection channel 10 and the inlet channel 11 into the small connecting rod bearing 3 , From the small connecting rod bearing 3 The oil then flows freely into a crank chamber not shown in detail, or on to an oil pan.

The connection channel 10 is in the embodiment shown a bore which extends from the surface FF into the piston cooling chamber 6 leads. The inlet channel 11 is in this embodiment also through a hole in the connecting rod 4 from the outer surface AA of the connecting rod 4 to the small connecting rod bearing 3 educated.

connecting channel 10 and inlet channel 11 can be considered essentially in a normal plane to the axis of rotation DD of the piston pin 2 extending bores be carried out, as for example in 1 is shown. The leaf level corresponds to a normal plane to the axis of rotation DD of the piston pin 2 , In principle, however, other courses are possible, which are inclined to such a normal plane. Moreover, while in the exemplary embodiment of the figures only one connection 10 and inlet channel 11 are shown, a plurality of such channels may also be provided in each case.

A disadvantage of such solutions is in particular that oil from the connecting channel 10 on the outer surface of the connecting rod 4 flows along in the direction of crankcase or oil sump and not in the inlet channel 11 and the connecting rod bearing 3 arrives.

To fix this problem and remove the oil from the connection channel 10 easier in the inlet channel 11 to be able to transport in the internal combustion engine according to the invention to the connecting rod 4 around at the surface FF of the piston 1 a catching element 13 arranged.

In other words, between the connecting rod 4 facing surface FF of the piston 1 and the outer surface AA the connecting rod 4 an that between the surfaces FF . AA volume limiting catchment element 13 arranged. The catch element 13 encloses the volume at least between the exit opening 10 " of the connection channel 10 and the outer surface AA the connecting rod 4 in the area of the inlet inlet opening 11 ' of the inlet channel 11 taking into account the relative movement of the outer surface AA the connecting rod 4 and the to the connecting rod 4 oriented area FF of the piston 1 to each other when used according to the invention of the internal combustion engine 1 ,

The catch element 13 has a base element 14 and - to limit the volume - of the base member 14 protruding Sealing elements in the form of lamellae or brush elements 15 on. The lamellae or bristles of the brush elements 15 are in the basic element 14 fixed. The basic element 14 can, depending on the embodiment of the connecting rod 4 facing surface FF of the piston 1 be arranged, with the mouth or outlet opening 10 " of the connection channel 10 within of the base element 14 covered area (see eg 4 ), or it is on the outside surface AA the connecting rod 4 arranged and the inlet inlet opening 11 ' of the inlet channel 11 is inside of the base element 14 covered area.

The brush elements 15 can cover the entire area BB of the base element 14 cover or in particular in the edge region of the base element 14 be arranged. In the latter case, the basic element 14 then, for example, executed as a ring. The length of the brush elements 15 is in accordance with the gap between pistons 1 and connecting rod 4 (or the connecting rod 4 facing surface FF of the piston 1 and the outer surface AA the connecting rod 4 ). If the base element 14 on the piston 1 is arranged, the brush elements are sufficient 15 to the outer surface AA the connecting rod 4 ; if the base element 14 on the connecting rod 4 is arranged, the brush elements are sufficient 15 to the connecting rod 4 facing surface FF of the piston 1 ,

Regardless of where the base element 14 is arranged, the collecting element 13 dimensioned so that both the exit opening 10 " of the connection channel 10 as well as the inlet inlet opening 11 ' of the inlet channel 11 during the intended use of the internal combustion engine according to the invention 1 within the catch element 13 limited volume.

In the illustrated embodiment, in particular the 1 and 3 it can be seen, is the basic element 14 , a ring of, for example, steel or aluminum in the piston 1 on the surface FF arranged, for example screwed, pressed, glued or permanently fixed in other ways. The catch element 13 points to the outer surface AA the connecting rod 4 facing side slats or brush elements 15 on that stuck to the base element 14 are connected. end up 16 the brush elements 15 , or the lamellae, are freely movable and touch in the embodiment shown, the outer surface AA the connecting rod 4 only a little. The bristles of the brush elements 15 are made of oil-repellent material, they can for example be made of metal, or of a durable plastic.

The catch element 13 or its base element 14 has in the embodiment shown an elliptical base BB on and covers the outside surface AA the connecting rod 4 in the circumferential direction of the piston pin 2 over an angle α, which is between 25 ° and 30 °, from. The angle α can be selected smaller or larger in other embodiments, but advantageously so that inlet channel 11 and connecting channel 10 during normal operation of the internal combustion engine and its occurring movements against each other in the collecting element 13 covered area remain. Apart from the elliptical shape are also any other shapes of the base BB of the collecting element 13 like oval, polygonal etc. possible.

If now oil from the piston refrigerator 6 over the connection channel 10 in the gap between the outer surface AA the connecting rod 4 and the area FF of the piston 1 flows, then the volume in this gap by the collecting element 13 limited and the required oil for lubrication and cooling is reduced. There can be more oil in the area of the small connecting rod bearing 3 reach. The volume between the brush elements 15 of the collecting element 13 fills with oil, preventing enormous leakage into the remaining gap between connecting rod 4 and pistons 1 and forwards the oil into the inlet channel 11 and the piston pin 2 ,

The catch element 13 can also act as a buffer between the connection channel 10 and the inlet channel 11 serve.

In 2 is a view of the piston 1 shown from below, with neither piston pin 2 still connecting rod 4 are shown. Between the shots 17 for the piston pin 2 is the catch element 13 at the connecting rod 4 facing surface FF of the piston 1 visible, noticeable. Within the collecting element 13 is the connection channel 10 in the piston 1 recognizable. The basic element 14 of the collecting element 13 is at a bulge 18 of the piston 1 on the surface FF arranged. Under bulge 18 Here, an increase in the piston surface in direction away from the combustion chamber direction to understand.

The detail III off 1 is in 3 shown. A flow direction of the oil is denoted by the reference numeral CC designated. The oil flows from the piston refrigerator 6 through the connection channel 10 in one of the collecting element 13 limited volume due to the brush elements 15 , or in other embodiments by fins, the outer surface AA the connecting rod 4 , and the to the connecting rod 4 oriented area FF of the piston 1 limited. Therein, the oil, or the means for lubrication and cooling is retained. Of this Volume between the brush elements 15 the oil continues to flow into the inlet channel 11 and to the small connecting rod bearing 3 , 6 shows a perspective view of only the collecting element 13 with the connection channel 10 , The base area BB of the collecting element 13 indicates at the position of the exit opening 10 " of the connection channel 10 a not shown recess.

The catch element 13 is with the base element 14 at the bulge 18 of the piston 1 arranged. The ends 16 the brush elements 15 touch the outer surface AA the connecting rod 4 , When pivoting the connecting rod 4 opposite the piston 1 give the brush elements 15 - as far as the connecting rod 4 touch at all - after and the friction between brush elements 15 and connecting rod 4 is small, thus the heat input is limited by the friction.

In 5 is the piston 1 in a section along the line VV in 2 shown. Dashed lines are the catching element 13 and the inlet channel 11 shown. The catch element 13 is above a rotation axis in the embodiment shown DD of the piston pin 2 arranged, ie with respect to an imaginary plane through the axis of rotation DD normal to a lifting axle EE of the piston 1 is the catch element 13 on the to the piston bottom 5 pointing side to the surface FF arranged.

In the direction of the axis of rotation DD of the piston pin 2 has the catch element 13 an extension, a width b to the smaller, or at most equal to the extent of a Pleuelaugenbreite in the same direction of the connecting rod 4 , In 5 the Pleuelaugenbreite extends along the axis of rotation DD of the piston pin 2 between the outsides of the connecting rod 4 in the area of the small connecting rod eye 30 ,

The solution according to the invention with the described collecting element 13 thus allows the formation of a retention volume between pistons 1 and connecting rod 4 , This will lubricate or cool that into corresponding volume within the piston 1 is introduced, above the inlet channel 11 to a connecting rod bearing 3 in a small connecting rod eye 30 a connecting rod 4 jammed and it can be almost guaranteed a permanent supply of the bearing bush with lubricant or coolant. By the execution of the collecting element 13 as a "brush seal" under brush elements 15 can be a wear-free contact between brush elements 15 and connecting rods 4 or piston 1 allows and radial tolerances between connecting rods 4 and pistons 1 be compensated.

Contrary to the solutions known in the prior art, this makes possible a permanent lubrication and cooling of the bearing bush, which is particularly the case with highly loaded engines, e.g. in the large engine area, is an advantage.

QUOTES INCLUDE IN THE DESCRIPTION

This list of the documents listed by the applicant has been generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Cited patent literature

• US 3,992,980 A [0004]

Claims (10)

Internal combustion engine having at least one piston (1) which can be moved back and forth in a cylinder and has a piston cooling chamber (6) for accommodating means for cooling and lubrication, the piston (1) being arranged via a piston pin (3) arranged in a small connecting-rod bearing (3). 2) is pivotally connected to a connecting rod (4) and between piston cooling chamber (6) and a connecting rod (4) oriented surface (FF) of the piston (1) at least one connecting channel (10) is provided and in the connecting rod (4) Supply channel (11) to the small connecting rod bearing (3) is arranged, characterized in that substantially between the connecting channel (10) and inlet channel (11) between the connecting rod (4) and piston (1) a collecting element (13) for collecting means for Cooling and lubrication is arranged. Internal combustion engine after Claim 1 , characterized in that the collecting element (13) comprises brush elements (15) and / or lamellae. Internal combustion engine after Claim 2 , characterized in that the collecting element (13) substantially with brush elements (15) and / or lamellae, connecting rod (4) and piston (1) defines an inner collecting volume, wherein the brush elements (15) and / or lamellae preferably annular around a the channels (10, 11) are arranged. Internal combustion engine according to one of Claims 2 or 3 , characterized in that ends (16) of the brush elements (15) and / or the lamellae are directed towards the outer surface (AA) of the connecting rod (4) and preferably contact the outer surface (AA). Internal combustion engine according to one of Claims 1 to 4 , characterized in that the collecting element (13) with a base element (14) on the connecting rod (4) oriented surface (FF) of the piston (1) is fixed. Internal combustion engine according to one of Claims 1 to 5 , characterized in that the collecting element (13) has a base (BB) which is elliptical, preferably circular. Internal combustion engine according to one of Claims 1 to 6 , characterized in that when pivoting the connecting rod (4), the collecting element (13) surrounds the inlet channel (11). Internal combustion engine according to one of Claims 1 to 7 , characterized in that the collecting element (13) in the circumferential direction forms an angle (α) of 25 ° to 30 °. Internal combustion engine according to one of Claims 1 to 8th , characterized in that the collecting element (13) has a width (b) in the direction of a rotational axis (DD) of the piston pin (2), which corresponds substantially to a Pleuelaugenbreite the connecting rod (4). Internal combustion engine according to one of Claims 1 to 9 , characterized in that the collecting element (13) above a rotational axis (DD) of the piston pin (2) is arranged.

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