CHECK VALVE FOR CONNECTING ROD FOR VARIABLE COMPRESSION INTERNAL COMBUSTION ENGINE

Abstract

The invention relates to a check valve for a connecting rod for a variable compression internal combustion engine including at least one hydraulic chamber, the check valve including a valve body with a fluid path that is openable and closable by at least one closure element, wherein the at least one closure element is provided as an annular band. The invention also relates to a connecting rod for a variable compression internal combustion engine including a least one hydraulic chamber that is connectable by the at least one check valve with a bearing shell or a supply connection of the connecting rod or another hydraulic chamber.

Claims

1. A check valve for a connecting rod for a variable compression internal combustion engine including at least one hydraulic chamber, the check valve comprising: a valve body with a fluid path that is openable and closable by at least one closure element, wherein the at least one closure element is provided as an annular band.

2. The check valve according to claim 1, wherein the annular band is radially openable towards an outside.

3. The check valve according to claim 2, wherein radially outward oriented protrusions are provided in a longitudinal direction on both sides of the at least one closure element and limit an axial movement of the at least one closure element.

4. The check valve according to claim 1, wherein the annular band is openable in a radially inward direction.

5. The check valve according to claim 4, wherein a radially inward oriented safety element is provided to limit an axial movement of the at least one closure element in a longitudinal direction.

6. The check valve according to claim 1, wherein ends of the annular band are configured overlapping in an installed position of the annular band.

7. The check valve according to claim 1, wherein ends of the annular band are arranged in an installed position of the annular band at a circumference of the valve body so that the ends of the annular band are oriented towards each other and offset from each other.

8. The check valve according to claim 7, wherein a bolt is provided which fixates the annular band in place.

9. The check valve according to claim 1, wherein the fluid path includes two partial paths which are openable and closable by the at least one closure element.

10. The check valve according to claim 9, wherein at least two closure elements are provided that are openable and closeable independently from each other.

11. A connecting rod for a variable compression internal combustion engine including a least one hydraulic chamber that is connectable by the at least one check valve according to claim 1 with a bearing shell or a supply connection of the connecting rod or another hydraulic chamber.

12. The connecting rod according to claim 11, wherein the at least one check valve is threaded or pressed into a connecting rod body of the connecting rod.

13. The connecting rod according to claim 11, wherein the at least one check valve is arranged below the hydraulic chamber and in a transversal bore hole of the connecting rod.

14. The connecting rod according to claim 11, comprising: two hydraulic chambers, wherein one of the at least one check valve is associated with each of the two hydraulic chambers.

15. The connecting rod according to claim 11, comprising two hydraulic chambers, wherein the at least one check valve is a single check valve that is provided for the two hydraulic chambers, and wherein the fluid path in the valve body includes partial paths which are respectively associated with one of the two hydraulic chambers.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Further advantages can be derived from the subsequent drawing description. The drawing figures schematically illustrate an embodiment of the invention. The drawing figures, the description and the patent claims include numerous features in combination. A person skilled in the art will advantageously also view the features individually and combine them into useful other combinations, wherein:

[0030] FIG. 1 illustrates a perspective view of a first embodiment of a check valve according to the invention;

[0031] FIG. 2 illustrates a side of the check valve according to FIG. 1;

[0032] FIG. 3 illustrates a first longitudinal sectional view of the check valve according to the FIG. 1;

[0033] FIG. 4 illustrates a cross sectionals view B-B of the check valve according to FIG. 1;

[0034] FIG. 5 illustrates a second longitudinal sectional view C-C of the check valve according to FIG. 1;

[0035] FIG. 6 illustrates a perspective view of a second embodiment of a check valve according to the invention;

[0036] FIG. 7 illustrates a side view of the check valve according to FIG. 6;

[0037] FIG. 8 illustrates a longitudinal sectional view A-A of the check valve according to FIG. 6;

[0038] FIG. 9 illustrates a cross sectional view B-B of the of the check valve according to FIG. 6;

[0039] FIG. 10 illustrates a perspective view of a third embodiment of the check valve according to the invention;

[0040] FIG. 11 illustrates a side view of the check valve according to FIG. 10;

[0041] FIG. 12 illustrates a first longitudinal sectional view A-A of the check valve according to FIG. 10;

[0042] FIG. 13 illustrates a second longitudinal sectional view B-B of the check valve according to FIG. 10;

[0043] FIG. 14 illustrates a cross sectional view C-C of the check valve according to FIG. 10;

[0044] FIG. 15 illustrates a perspective view of a fourth embodiment of a check valve according to the invention;

[0045] FIG. 16 illustrates a top view of the check valve according to FIG. 15;

[0046] FIG. 17 illustrates a first longitudinal sectional view of the check valve according to FIG. 15;

[0047] FIG. 18 illustrates a first cross sectional view B-B of the check valve according to FIG. 15;

[0048] FIG. 19 illustrates a second cross sectional view of the check valve according to FIG. 15;

[0049] FIG. 20 illustrates a third cross sectional view of the check valve according to FIG. 15;

[0050] FIG. 21 illustrates a side view of the check valve according to FIG. 15;

[0051] FIG. 22 illustrates a second longitudinal sectional view E-E of the check valve according to FIG. 15; and

[0052] FIG. 23 illustrates a connecting rod according to an embodiment of the invention in a front view.

DETAILED DESCRIPTION OF THE INVENTION

[0053] In the figures identical or like components are designated with reference numerals which are increased by 100 respectively in the different embodiments. Repetitive descriptions are thus omitted. The figures show only embodiments and do not limit the spirit and scope of the invention.

[0054] The subsequently described check valves are advantageously used in a connecting rod for a variable compression internal combustion engine of a motor vehicle which is described in an exemplary embodiment in DE 10 2013 107 127 A1. The check valves, however can also be used in other embodiments of a connecting rod 501 for an internal combustion engine with variable compression as illustrated e.g. in FIG. 23 which includes at least one hydraulic chamber 510, 511 which is connectable by the check valve 101 with a bearing shell 514 or a supply connection P, e.g. a tank of the connecting rod 501, wherein the check valve 501 prevents a back flow to the bearing shell 514 or to the supply connection P. The check valve 101 can thus be provided directly below the hydraulic chamber 510, 511 or in a transversal bore hole 540, 541 of the connecting rod 501.

[0055] From FIGS. 1-5 various views and sectional views of a first embodiment of a check valve 1 according to the invention can be derived. The check valve 1 includes a valve body 3 arranged in a valve housing 2 and including a fluid path 4 which is indicated by arrows in the longitudinal sectional view A-A according to FIG. 3. The fluid path 4 is operable and closable by a closure element 5. It is evident that the closure element 5 is provided as an annular band which closes one or more openings 6 in the valve body 3. The annular band can be implemented for example as an elastic sheet metal band. Under a pressure that is predetermined by the annular band the annular band opens in a radially outward direction and facilitates a fluid flow into the non-illustrated hydraulic chamber of the connecting rod.

[0056] Ends of the annular band do not overlap in the first embodiment, thus a bolt 7 is provided in order to secure the annular band in position, wherein the bolt is arranged between both ends of the annular butt joint so that a rotation of the annular band can be prevented reliably. Securing the annular band in position axially is performed by a circumferential shoulder 8 of the valve element 3 and a valve cover 9 whose pass through bore holes 10 form a portion of the fluid path 4 and which is advantageously pressed into the valve housing 2.

[0057] The valve housing 2 can be threaded by a thread 11 into a connecting rod body of the connecting rod.

[0058] A second embodiment of a check valve 101 according to the invention can be derived from FIGS. 6-9. The check valve 101 only includes one valve body 103 which can be pressed into the connecting rod body of the connecting rod. A closure element 105 is also provided as a radially outward opening annular band which is secured in position by a bolt 107 arranged between the open butt joint ends of the annular band so that the annular band closes openings 106 of the valve body 103 reliably. Securing the annular band axially against a sliding in the longitudinal direction L is provided by radially outward oriented circumferential protrusions 112 and 113 of the valve body 103. The fluid path 104 is partially provided by an axial dead hole 114 which is closed tight by a bearing ball plug 115. As evident in particular from FIGS. 8 and 9 the fluid path 104 includes a transversal bore hole 116 which is connected with the supply connection P in the connecting rod and openings 106 configured as transversal bore holes which lead into the dead hole 114.

[0059] In order to provide axial positioning the bolt 7 or 107 can also protrude through a bore hole of the annular band.

[0060] The third embodiment of a check valve 201 according to the invention that is illustrated in FIGS. 10-14 includes an annular band as a closure element 205 which differs from the first two embodiments, wherein the annular band is openable in a radially inward direction and ends of the annular band overlap in the installed position. Thus, the annular band closes the radially outward oriented openings 206 of the valve body 203 in the installed position. The annular band is arranged in a step shaped recess 217 of the valve body 203 which is threaded into the piston body by a thread 211. A circumferential safety element 218 that is pressed into the recess 217 and oriented radially inward prevents the annular band from sliding out.

[0061] The fluid path 204 runs through a central bore hole of the safety element 218 into an interior of the valve body 203 and the annular band. Thus, the hydraulic fluid can flow radially inward when opening the annular band according to the fluid path 204 through the openings 206 in a radially outward direction to the hydraulic chambers of a connecting rod.

[0062] The check valves 1, 101, 201 described supra are respectively associated with a hydraulic chamber of a connecting rod.

[0063] According to the fourth embodiment illustrated in FIGS. 15-22 a single check valve 301 is provided for both hydraulic chambers of a connecting rod. For this purpose a valve body 303 includes three annular grooves 320, 321, 322. In the annular grooves 320 and 322 a radially outward openable closure element 305 is provided in a form of an annular band which closes openings 306 that are connected with the hydraulic chambers. The annular band is respectively secured by a bolt 307 against a rotation in the circumferential direction.

[0064] Plural openings 306 that are arranged in the annular grooves 320 and 322 are connectable with a hydraulic chamber. A fluid path 304 is partially formed by an axial dead hole 314 which is closed tight by a bearing ball plug 315. As evident in particular from FIGS. 17 and 20 the fluid path 304 includes transversal bore holes 316 arranged in the annular groove 321 and connected with the supply connection P and openings 306 configured as transversal bore holes in the ring grooves 320, 322 wherein the openings lead as partial paths 324, 325 into the dead hole 314. Arranging the two separate closure element 305 in the grooves 320 and 322 of the valve body 303 facilitates opening and closing both partial paths 324, 325 independently from each other.

[0065] FIG. 23 illustrates a front view of a connecting rod 501 according to the invention for a variable compression internal combustion engine with check valves 101 in a schematic view in a high compression position designated as E-high. The connecting rod 501 includes an eccentrical element adjustment device 502 for adjusting an effective connecting rod length. The eccentrical element adjustment device 502 includes an eccentrical element 504 cooperating with a one component or multi component eccentrical element lever 503. Thus, an adjustment travel of the eccentrical element adjustment device 502 is adjustable by a switch valve 505.

[0066] A rotation of the eccentrical element adjustment device 502 is initiated by an influence of mass forces and gas forces of the internal combustion engine which impact the eccentrical element adjustment device 502 during an operating stroke of the internal combustion engine. During the operating stroke the effective directions of forces impacting the eccentrical element adjustment device 502 change continuously. The rotating movement or adjustment movement is supported by a piston 506, 507 loaded with hydraulic fluid, in particular motor oil and integrated in the connecting rod 501 or the pistons 506, 507 prevent a reset of the eccentrical element adjustment device 502 due to varying force effective directions of forces impacting the eccentrical element adjustment device 502.

[0067] The pistons 506, 507 are operatively connected by eccentrical element rods 508, 509 on both sides with the eccentrical element lever 503 of the eccentrical element adjustment device 502. The pistons 506, 507 are movably arranged in the hydraulic chambers 510, 511 and loaded with the hydraulic fluid through check valves 101 through hydraulic fluid conduits from the bearing shell 514 of the crank bearing eye 515. The check valves thus prevent a back flow of the hydraulic fluid from the hydraulic chambers 510, 511 into the hydraulic fluid conduits into the bearing shell 514 of the crank bearing eye 515 or a tank and facilitate sucking additional hydraulic fluid into the hydraulic chambers 510, 511. The hydraulic chambers 510, 511 are connected with additional hydraulic fluid conduits which cooperate with the switch valve 505. The switch valve 505 is also connected with the bearing shell 514 through two hydraulic fluid conduits.

[0068] The two check valves 101 are also respectively arranged in the connecting rod body 522 in the transversal bore holes 540, 541 and connected through hydraulic fluid conduits with the bearing shell 514, wherein the check valves 101 can be pressed in or threaded in.

[0069] Alternatively check valves 101 could also be arranged below the hydraulic chambers 510, 511.

[0070] In the embodiment illustrated in FIG. 23 a respective check valve 101 is associated with a hydraulic chamber 510, 511. Alternatively, however also only one single check valve 301 (c.f. FIGS. 15-22) can be provided for both hydraulic chambers 510, 511 wherein the fluid path 304 includes partial paths 324, 325 in the valve body 303 in this embodiment, wherein the partial paths 324, 325 are respectively connected through hydraulic fluid conduits with a hydraulic chamber 510, 511.

[0071] Another non-illustrated embodiment of a connecting rod according to the invention with two hydraulic chambers 510, 511 provides that the check valve according to the invention facilitates connecting a hydraulic chamber 511 (the hydraulic chambers of the gas force side) with the other hydraulic chamber 510 (hydraulic chamber 510 of the mass force side) so that the other hydraulic chamber 510 is fed by the hydraulic chamber 511 of the gas force side.