GB2620572A

GB2620572A - Valve guide, valve, valve assembly, cylinder head, and piston engine

Info

Publication number: GB2620572A
Application number: GB2210147.1A
Authority: GB
Inventors: Guisasola Inigo
Original assignee: Caterpillar Energy Solutions GmbH
Current assignee: Caterpillar Energy Solutions GmbH
Priority date: 2022-07-11
Filing date: 2022-07-11
Publication date: 2024-01-17
Also published as: GB202210147D0; DE102023118344A1

Abstract

A valve guide 10 for a cylinder head 300 of a piston engine, the valve guide 10 comprising a valve guide portion 12, configured to guide a valve 100 along a valve guide direction (D), and at least one mounting device 14. The mounting device 14 is configured to allow an angular deflection (α) of the valve guide portion 12 relative to a nominal valve guide direction (N, fig.1). The mounting device 14 may comprise a joint connection, such as a ball joint, thereby, the valve guide portion 12 may be adjusted to the required angular deflection and a separation of functions “valve guiding” and “valve momentum compensation” may be achieved, so that only loads in the direction of the valve guide direction (D) act on the valve 100. The present invention also pertains to a valve 100 suitable for use in a valve guide 10 according to the present invention, and a valve assembly (200).

Description

Valve guide, valve, valve assembly, cylinder head, and piston engine Technical Field [0001] The present disclosure pertains to a valve guide for a cylinder head of a piston engine of the internal combustion ICE type, in particular a gas engine. The present disclosure further pertains to a valve suitable for use in such valve guide, and a valve assembly comprising such valve guide and valve. Further, the present disclosure pertains to a cylinder head comprising at least one such valve assembly, and to a piston engine comprising at least one such a cylinder head.

Technological Background

[0002] As with most cylinder heads of piston engines, cylinder heads tend to deform over time due to high temperatures. Valve guides, which are inherent components of most cylinder heads, are also subject to such deformation.

[0003] In some cases, the cylinder head deformation has been observed to have an S-shape, causing the clearance between valve guide and valve stern to decrease at one or more positions along the guide length. A too low clearance between valve guide and valve stern however leads to lateral contact pressure points between valve and valve guide, which are associated with increased wear of the valve guide and/or the valve.

[0004] The valve guide, the valve, the valve assembly, the cylinder head, and the piston engine of the present disclosure solve one or more problems set forth above.

Summary of the invention

[0005] Starting from the prior art, it is an objective to provide a simple, cost-effective, and reliably operating valve guide for a cylinder head of a piston engine.

I00061 This objective is solved by means of a valve guide with the features of claim 1, a valve with the features of claim 10, a valve assembly with the features of claim 11, a cylinder head with the features of claim 14, and a piston engine with the features of claim 15. Preferred embodiments are set forth in the present specification, the Figures as well as the dependent claims.

[0007] Accordingly, a valve guide for a cylinder head of a piston is provided.

The valve guide comprises a valve guide portion configured to guide a valve along a valve guide direction, and at least one mounting device. The mounting device is configured to allow an angular deflection of the valve guide portion relative to a nominal valve guide direction.

[0008] Furthermore, a valve suitable for use in a valve guide according to the present disclosure is provided, the valve comprising a valve stem and a valve head.

[0009] Moreover, a valve assembly for a cylinder head of a piston engine is provided, comprising a valve guide according to the present disclosure, and a valve according to the present disclosure.

[0010] In addition, a cylinder head is provided, comprising at. least one valve

assembly according to the present disclosure.

[0011] Further, a piston engine is provided, comprising at least one cylinder

head according to the present disclosure.

Brief description of the drawings

[0012] The present disclosure will be more readily appreciated by reference to the following detailed description when being considered in connection with the accompanying drawings in which: [0013] Figure 1 schematically shows a valve guide for a cylinder head according to a first embodiment in a side view; [0014] Figure 2 schematically shows a valve guide for a cylinder head according to a further embodiment in a side view; I00151 Figure 3 schematically shows the valve guide of Figure 2 according to a development in a side view; WON Figure 4 schematically shows a valve guide for a cylinder head according to another embodiment in a side view; [0017] Figure 5 schematically shows a valve assembly for a cylinder head according to a first embodiment; [0018] Figure 6 schematically shows a valve assembly for a cylinder head according to another embodiment; and [0019] Figure 7 schematically shows a cylinder head according to an embodiment in a side view.

Detailed description of preferred embodiments

WON In the following, the invention will be explained in more detail with reference to the accompanying figures. In the Figures, like elements are denoted by identical reference numerals and repeated description thereof may be omitted in order to avoid redundancies.

[0021] The present disclosure is generally directed to valve guide applications in piston engines, in particular to reciprocating piston engines of the internal combustion engine, ICE, type. Such engines may include stationary gas engines.

[0022] The underlying principle of the present disclosure is based on the observation that valve guide deformation inflicted valve wear can in fact be mitigated or avoided by allowing a small angular valve guide deflection relative to its nominal valve guide direction. This approach is in stark contrast to the widely held but herewith overcome opinion that a valve guide direction is not to be deviated from, as the latter is assumed to reduce sealing between valve head and valve seat. In any case, the benefits of providing such an angular deflection have been proven outperforming any associated drawbacks.

[0023] In Figure 1, a valve guide 10 for a cylinder head 300 of a piston engine is schematically shown in a side view according to a first embodiment.

Accordingly, the valve guide 10 comprises a valve guide portion 12 configured to guide a valve 100 along a valve guide direction D. The valve guide 10 further comprises at least one mounting device 14, configured to allow an angular deflection a of the valve guide portion 12 relative to a nominal valve guide direction N. [0024] The valve guide portion 12 may allow a relative movement of the valve 100 along the valve guide direction D. Accordingly, the valve guide portion 12 may be any interface suitable for guiding a valve 100 along the valve guide direction D. [0025] Further, the valve guide portion 12 may be configured such that in a state when a valve 100 is mounted, a predetermined clearance C between the valve 100 and the valve guide portion 12 is provided.

[0026] The mounting device 14 may be configured to mount the valve guide to an adjacent component. For example, the mounting device 14 may be configured to mount the valve guide 10 to an adjacent cylinder head 300. Further, the valve guide portion 12 may be a part of the mounting device 14. For example, the valve guide portion 12 may be a surface of the mounting device 14.

[0027] When the valve guide 10 is mounted to an adjacent component, for example a cylinder head 300, the valve guide portion 12 may guide a valve 100 along the valve guide direction D. [0028] The valve guide direction D may be understood as a direction, into which a valve 100 would be guided by the valve guide portion 12 (if a valve 100 is present). Hence, the valve guide direction D may be understood as the actual. or current, valve guide direction D. [0029] The nominal valve guide direction N may be the ideal, or theoretical valve guide direction N. In other words, when the cylinder head deformation 320 is zero or small, the valve guide direction D may be identical to the nominal valve guide direction N. Accordingly, during operation of a cylinder head having no deformations, the valve 100 may reciprocate along the valve guide direction D which is identical to the nominal valve guide direction N. [0030] However, if a cylinder head deformation 320 is present, the valve guide direction D may deviate from the nominal valve guide direction N by an angular deflection a.

[0031] Hence, the angular deflection a of the valve guide portion 12 relative to the valve guide direction D may be understood as a quantifier of the amount in which the valve guide direction D differs from the nominal valve guide direction N. [0032] The angular deflection a of the valve guide portion 12 relative to the valve guide direction D may be understood as an additional degree of freedom. Because of the angular deflection a, the valve guide 10 has self-adjusting properties, adjusting to cylinder head deformations 320, for example temperature-induced cylinder head deformations. This has the advantage that structurally introduced deviations from the nominal valve guide direction N may be compensated by the valve guide 10 without inflicting a bending momentum into the valve 100.

[0033] According to the illustration provided by Figure 1, the valve guide 10 is configured to guide a valve 100, which is partly shown. Upon actuation, and in an ideal case the valve 100 may reciprocate up and down along the nominal valve guide direction N. However, due to the cylinder head deformations 320, exemplarily shown in the lower part of the cylinder head 300 in the elliptical cutout, the actual valve guide direction D deviates from the nominal valve guide direction D by the angular deflection a.

[0034] According to the example shown in Figure 1, the nominal valve guide direction D may pivot about its fixation in the mounting device 14 relative to the nominal valve guide direction N in the amount of the angular deflection a. This pivotal movement is in fact a very slow as it occurs as a function of the cylinder head deformation 320.

[0035] The mounting device 14 of the valve guide may further comprise a joint connection, preferably a ball joint connection 16. Thereby, the valve guide portion 12 may be adjusted according to the required angular deflection a.

[0036] Using a joint connection, a separation of functions "valve guiding" and "valve momentum compensation" may be achieved, in particular when using the ball joint connection 16. The valve guide portion 12 allows moving the valve 100 along the valve guide direction D irrespective of the angular deflection a. The mounting device 14, configured to allow an angular deflection a, allows that lateral forces acting upon the valve is dissipated by the angular deflection a. Thereby, a lateral force applied to the valve 100 does not lead to lateral pressures acting on the valve 100. Hence, only loads in the direction of the valve guide direction D act on the valve 100.

[0037] The mounting device 14 in the shape of a ball joint connection 16 may comprise an inner ring 17 and an outer ring 19. The outer ring 19 may be fixed to the cylinder head 300 axially using axial fastening means 28, such as inner rings, shoulder bores, sleeves, or the like. The inner ring 17 may have a convex surface configured to engage a complementary concave surface of the outer ring 19. The surfaces may be spheiical. Further, the inner ring 17 may comprise a cylindrical bore on its inside, facing the valve 100, and providing the valve guide portion 12.

[0038] The angular deflection a may comprise a range of 0.01 to 0.5 degrees.

[0039] In Figure 2, a valve guide 10 according to another embodiment is schematically shown in a side view. Unless stated otherwise, the same explanations, principles, and definitions provided in the context of Figure 1 also apply to the embodiment of Figure 2. The embodiment of Figure 2 differs from the embodiment of Figure 1 in that the guided portion 12 may comprise a guide tube 18, wherein the guide tube 18 comprise a first end 20 and a second end 22, and wherein the mounting device 14 is mounted on the first end. According to this embodiment, the guide portion 12 may be understood as the entire inner surface of the guide tube 18 facing the valve 100. The first end 20 may be an end proximal to a camshaft (not shown in Figure 2). Likewise, the second end 22 may be the distal end to the camshaft.

[0040] The inner ring 17 of the mounting device 14 may be pressed onto the guide tube 18 such that it is axially fixed thereon. According to an optional development, the valve guide 10 may further comprise a dampening device 30, configured to dampen fluctuations of the valve guide portion 12 in the range of the angular deflection a. Thereby, dynamic lateral loads acting on the valve 100 and the valve guide 10 may be dampened, and stability of the valve guide 10 may be increased during operation. Further, the dampening device 30 may be configured to compensate for Eigenfrequencies. It will be appreciated by the person skilled in the art that the design of the dampening device must occur on a case-by-case basis, usually by utilizing simple experiments to identify an optimum in dampening characteristics.

[0041] In Figure 3, a further development of the valve guide 10 of Figure 2 is shown in a side view. Also here, the same principles, explanations, and definitions provided in the context of Figures 1 and 2 apply where applicable. The development of Figure 3 differs from the embodiment of Figure 2 in that the valve guide 10 may further comprise a second mounting device 24, provided on the second end 22 of the guide tube 18. In addition, the second mounting device 24 may comprise a second joint connection, preferably a second ball joint connection 26.

[0042] The provision of first and second mounting devices 14,24 can increase the bearing stability of the valve 100 in the valve guide 10. More specifically, the provision of first and second mounting devices 14, 24 has the advantage of being able to realize a determined bearing configuration which increases stability of a valve 100 in the valve guide 10. Such a determined bearing configuration may be realized in different ways, depending on expected loads, and expected thermal expansion of cylinder head 300 and valve guide 10. For example, as shown in Figure 3, the valve guide 10 may be arranged in a fixed/floating bearing configuration. The first mounting device 14 may be the fixed bearing, axially fixed to the cylinder head 300 by fastening means 28. The second mounting device 24 may be the floating bearing without axial fixation to the cylinder head 300.

[0043] The person skilled in the art will appreciate that further bearing combinations, not shown in Figure 3, may also be considered, in particular X-or 0-bearing configurations. Likewise, the person skilled in the art will appreciate that different types of axial fixation devices 28 for fixing a mounting device 14 to the guide tube and/or the cylinder head 300 may be used.

[0044] The first mounting device 14 in the shape of a ball joint connection 16 may comprise an inner ring 17 and an outer ring 19. The outer ring 19 may be fixed to the cylinder head 300 axially using axial fastening means 28, such as inner rings, shoulder bores, sleeves, or the like. The inner ring 17 of the first mounting device 14 may have a convex surface configured to engage a complementary concave surface of the outer ring 19. Further, the inner ring 17 may be pressed onto the valve guide portion 12 such that it is axially fixed thereon.

[0045] Likewise, the inner ring 27 of the second mounting device 24 in the shape of a second ball joint connection 26 may also be pressed on the guide tube 18 such that it is axially fixed thereon. The outer ring 29 of the second mounting device 24 may for example not be fixed axially. To this end, a fixed/floating bearing configuration may be achieved. Naturally, the fixed/floating bearing configuration may also be switched between the first and second mounting device 14, 24. According to further embodiments, not shown in the Figures. X-, or 0-bearing configurations may also be possible.

[0046] In Figure 4, a further embodiment of a valve guide 10 according to the present disclosure is shown in a side view. Unless stated otherwise, the same principles, explanations, and definitions provided in the context of Figures 1-3 apply where applicable. Accordingly, the valve guide 10 according to the embodiment of Figure 4 may comprise a first mounting device 14 and a second mounting device 24, yet no connecting guide tube 18. Instead, the first and second mounting devices 14, 24 may each be axially fixable to the cylinder head 300 using axial fastening means 28, engaging with the outer rings 19, 29 of the first and second mounting devices 14, 24, and the cylinder head 300, respectively. Both the first and second mounting devices 14, 24 may comprise a joint connection, preferably a ball joint connection 16, 26, respectively. According to this embodiment, the valve guide 10 may comprise two valve guide portions 12, namely a first valve guide portion 12 provided on an inner surface of the inner ring 17 of the first mounting device 14, aml a second valve guide portion 13 provided on an inner surface of the inner ring 27 of the second mounting device 24. Also with this embodiment, a self-adjusting valve guide 10 is achieved, suitable for compensating structural deformations in the cylinder head 300.

[0047] In Figure 5, a valve assembly 200 for a cylinder head 300 according to an embodiment is shown in a side view. Accordingly, the valve assembly 200 is suitable for a cylinder head 300 of a piston engine (not shown) and comprises a valve guide 10 according to the present disclosure and a valve 100 according to the present disclosure. To this end, the valve 100 comprises a valve stem 110 and a valve head 120. Pertaining to the valve guide 10 and the valve 100, the respective principles, explanations, and definitions provided herein apply where applicable.

[0048] Further, the valve assembly 200 may comprise a valve scat 210, wherein the valve head 120 and/or the valve seat 210 may be configured such that the angular deflection of the valve 100 is accommodated such that the valve head 120 and the valve seat 210 can be brought together in a sealed manner. For example, the valve head 120 and/or the valve seat 210 may have an elastic contact portion, allowing that the valve head 120 and the valve seat 210 can be brought together in a sealed manner. Thereby, operation of the valve assembly 200 may be achieved over the entire range of angular deflections.

[0049] In Figure 6, a valve assembly 200 for a cylinder head 300 according to a further embodiment is shown in a side view. Unless stated otherwise, the same principles, explanations, aml definitions provided in the context of Ihe embodiment shown in Figure 5 apply where applicable.

[0050] The embodiment shown in Figure 6 differs from the embodiment shown in Figure 5 in that the valve assembly 200 comprises the valve 100 as the first valve 100A, and the valve guide 10 as a first valve guide 10A, and further comprises a second valve 100B and a second valve guide 10B. In addition, the valve assembly comprises a valve bridge 220 mechanically coupling the first and second valves 100A, 100B. Preferably, the valve bridge 220 may comprise means to allow an angular displacement of the valves relative to the bridge, such that individual an angular deflection of the valves 100A, 100B is possible.

[0051] In Figure 7, a cylinder head 400 according to an embodiment is shown in a side view. The cylinder head 400 comprises at least one valve assembly 200 according to the present disclosure. Pertaining to the valve assembly 200, the same principles, definitions, and explanations provided in the context of Figures 5 and 6 apply where applicable. According to the embodiment of the valve guide 10 of Figure 7, the valve guide 10 may comprise a guided portion 12 having a length L which is shorter than a cylinder head mount thickness 310. Thereby, the impact. of a cylinder head deformation 320 on the valve guide 10 may be reduced.

[0052] It will be obvious for a person skilled in the art that these embodiments and items only depict examples of a plurality of possibilities. Hence, the embodiments shown here should not be understood to form a limitation of these features and configurations. Any possible combination and configuration of the described features can be chosen according to the scope of the invention.

[0053] A valve guide for a cylinder head of a piston engine may be provided, the valve guide comprising a valve guide portion, configured to guide a valve along a valve guide direction, and at least one mounting device. The mounting device is configured to allow an angular deflection of the valve guide portion relative to a nominal valve guide direction.

[0054] According to the present disclosure, the valve guide portion may allow relative displacement of a valve along the valve guide direction. The mounting device may, according to its literal meaning, be configured to mount the valve guide to an adjacent component. The valve guide portion may be a part of the mounting device, for example a surface thereof. The valve guide direction is the actual guide direction, along which a valve is guided by the valve guide portion. The nominal valve guide direction is a theoretical, nominal valve guide direction corresponding to a case when no cylinder head deformation is present. The angular deflection a may be understood as a quantifier of the amount in which the valve guide direction differs from the nominal valve guide direction.

[0055] Providing a mounting device which is configured to allow an angular deflection of the valve guide portion relative to a nominal valve guide direction has the advantage that deformations of the cylinder head, for example temperature-induced deformations, may be compensated in such a way that no increased loads, pressures, wear, and/or tear is observed at the valve operated in a deformed cylinder head.

[0056] Due to the allowed angular deflection, a lateral force acting on a valve guided in the guiding portion of the valve guide will simply lead to an angular deflection a, thereby dissipating said forces. Hence, only loads in the direction of the valve guide direction act on the valve. As a result, the friction observed between valve and guide portion is not a function of the cylinder head deformation. Only the angular deflections a is a function of the cylinder head deformation. Since friction in the guide portion remains the same, also wear in the guide portion remains the same. Thereby, increased wear of the valve due to cylinder head deformation can be avoided.

[0057] Providing a mounting device which is configured to allow an angular deflection of the valve guide portion relative to a nominal valve guide direction has the advantage that the valve guide may be self-adjusting to cylinder head deformations, in particular temperature-induced cylinder head deformations.

[0058] According to a development of the valve guide, the mounting device may comprise a joint connection, preferably a ball joint connection. Thereby, a separation of concerns, or functions, may be achieved conveniently. While the valve guide portion fulfills the function "valve guiding", the mounting device fulfills the function "valve momentum compensation".

[0059] Providing a joint connection has the advantage that such components are readily available, cheap, and reliable components well understood in theory.

[0060] Utilizing a ball joint connection has the advantage of allowing a spherical bearing interface, comprising a convex spherical shape engaging with a concave spherical shape. Such an interface is comparably simple to manufacture and has the further advantage that the engaged surface area remains constant for all observed angular deflections. Further, the engaged surface area of ball joint connections is maximal, which results in a minimum in pressure for a given load acting on the bearing interface. Thereby, a smooth and reliable operation of the valve guide may be provided at relatively low manufacturing and maintenance costs.

[0061] According to a further development of the valve guide, the angular deflection may comprise a range of 0.01 to 0.5°. Thereby, the clearance between the guide portion and the valve may be set very small, more specifically, smaller than the range of 0.01 to 0.5°. Thereby, the functions "guiding the valve" and "compensating valve momentum" can be optimized further. Thereby, increased wear of the valve due to cylinder head deformation can be avoided.

[0062] According to a further development of the valve guide, the guided portion may comprise a guide tube having a first end and a second end, wherein the mounting device is provided on the first end. The guide tube has the advantage that a lateral force acting on a valve, for example due to a deformation in the cylinder head, can be dissipated to the mounting device across a large surface area, hence, at low pressure and low friction. Thereby, increased wear of the valve due to cylinder head deformation can be avoided. Further, providing a guide tube has the advantage of reducing the risk of vibrations in the valve stem, which also reduces valve stem friction. Thereby, increased wear of the valve stem can be avoided, and durability of the valve guide and valve can be increased.

[0063] Providing the mounting device on a first end of the guide tube increases the overall stability of the valve guide, as in this case, dynamic loads acting on the valve guide and the valve are less likely to incite vibrations. This also applies to embodiments having the mounting device provided on the second end of the guide tube.

[0064] According to a further development of the valve guide, the guide portion may comprise a second mounting device, provided on its second end. Thereby, the overall stability of the valve guide can be improved, as dynamic loads acting on the valve and on the valve guide can be compensated more effectively.

[0065] According to a further development of the valve guide, the second mounting device may comprise a second joint connection, preferably a second ball joint connection. Thereby, complex deformations of the cylinder head may be compensated by the valve guide, in particular S-shaped deformations of the cylinder head.

[0066] According to a further development of the valve guide, the valve guide may further comprise axial fastening means for securing the first and/or second mounting devices, wherein the first and second mounting devices may be arranged in a fixed/floating, X-, or 0-bearing configuration. Providing a fixed/floating bearing configuration has the advantage of being able to compensate thermal expansions of the valve guide, the valve, and/or the cylinder head during operation without a reduction in operational stability.

[0067] According to a further development of the valve guide, the valve guide may further comprise a dampening device, configured to dampen fluctuations of the valve guide portion about the angular deflection. Thereby, friction between the valve and the valve guide portion can be minimized, which leads to less wear observed at the valve guide and/or the valve. Thereby, valve guide and valve operation reliability may be improved.

[0068] According to a further development of the valve guide, the guided portion may have a length shorter than a cylinder head mount thickness.

Providing a valve guide with reduced length has the advantage of reducing the impact of potential cylinder head deformations on the valve guide. For example, cylinder head deformations occurring below or above the valve guide may have no impact on the valve guide.

[0069] A valve suitable for use in a valve guide according to the present disclosure may be provided, the valve comprising a valve stem, and a valve head. The valve stem may be configured such as to be slidably guided within the guide portion of the valve guide. For example, the valve stem may be configured such that a clearance between valve stem and valve guide portion is present when the valve stem is inserted into the valve guide portion.

[0070] The valve head may be configured to be brought into a sealed fit with a valve seat over the entire range of possible angular deflections.

[0071] A valve assembly for a cylinder head of a piston engine may be provided, comprising a valve guide according to the present disclosure, and a valve according to the present disclosure. Hereto, the same principles, definitions, and explanations provided for the valve guide according to the present disclosure apply where applicable.

[0072] According to a further development of the valve assembly, the valve assembly may further comprise a valve seat, wherein the valve head and/or the valve seat may be configured such that the angular deflection of the valve is accommodated such that the valve head and the valve seat can be brought together in a sealed manner. For example. the valve head and/or the valve seat may have an elastic contact portion. allowing that the valve head and the valve seat can be brought together in a sealed manner. Thereby, operation of the valve assembly may be achieved over the entire range of angular deflections.

[0073] According to a further development of the valve assembly, the valve assembly may further comprise the valve as a first valve, further comprising a second valve, and a valve bridge mechanically coupling the first and second valves. Providing a valve bridge has the advantage that multiple valves can be actuated by a single cam of a camshaft. Preferably, the valve bridge may comprise means to allow an angular displacement of the valves relative to the bridge, such that individual an angular deflection of the valves is possible.

[0074] A cylinder head may be provided, comprising at least one valve assembly according to the present disclosure. Hereto, the same principles, definitions, and explanations provided for the valve assembly and the valve guide according to the present disclosure apply where applicable.

[0075] A piston engine may be provided, comprising at least one cylinder head according to the present disclosure. Hereto, the same principles, definitions, and explanations provided for the cylinder head, the valve assembly, and the valve guide according to the present disclosure apply where applicable.

Industrial applicability

[0076] With reference to the Figures, a valve guide for a cylinder head of a piston engine, a valve, a valve assembly, a cylinder head, and a piston engine, for example internal combustion engines ICEs is provided.

[0077] In practice, a valve guide for a cylinder head of a piston engine, a valve, a valve assembly, a cylinder head, and a piston engine and/or any combination of these various assemblies and components may be manufactured, bought, or sold to retrofit a gas engine, or a gas engine already in the field in an aftermarket context, or alternatively may be manufactured, bought, sold, or otherwise obtained in an OEM (original equipment manufacturer) context.

[0078] As alluded to previously herein, the aforementioned developments may provide a simple, cost-effective and reliably operating cooling system for a gas engine piston.

[0079] Referring to Figure 1, there is an embodiment shown disclosing a valve guide for a cylinder head of a piston. The valve guide comprises a valve guide portion configured to guide a valve along a valve guide direction, and at least one mounting device. The mounting device is configured to allow an angular deflection of the valve guide portion relative to a nominal valve guide direction. One skilled in the art will expect that various developments of the present disclosure will cause a reduced wear of a valve guide and/or valve during operation a cylinder head having a cylinder head deformation. Thereby, necessitating less maintenance and allowing prolonged service life of valve guide and valve.

[0080] The same advantages apply to the remaining figures, in particular to the gas engine comprising such valve guides and such valves.

[0081] The present description is for illustrative purposes only and should not be construed to narrow the breadth of the present disclosure in any way. Thus, those skilled in the art will appreciate that various modifications might be made to the presently disclosed developments without departing from the full and fair scope and spirit of the present disclosure. Other aspects, features and advantages will be apparent upon an examination of the attached drawings and appended claims. As used herein, the articles "a" and "an" are intended to include one or more items and may be used interchangeably with "one or more." Where only one item is intended, the term "one" or similar language is used. Also, as used herein, the terms "has," "have," "having," "include", "includes", "including", or the like are intended to be open-ended terms. Further, the phrase "based on" is intended to mean "based, at least in part, on" unless explicitly stated otherwise.

[0082] All references to the disclosure or examples thereof are intended to reference the particular example being discussed at that point and are not intended to imply any limitation as to the scope of the disclosure more generally. All language of distinction and disparagement with respect to certain features is intended to indicate a lack of preference for those features, but not to exclude such from the scope of the disclosure entirely unless otherwise indicated.

[0083] Recitation of ranges of values herein arc merely intended to serve as a shorthand method of referring individually to each separate value falling within the range, unless otherwise indicated herein, and each separate value is incorporated into the specification as if it were individually recited herein.

[0084] Certain steps of any method may be omitted, performed in an order that is different than what has been specifically mentioned or in some cases performed simultaneously or in sub-steps. Furthermore, variations or modifications to certain aspects or features of various developments may be made to create further developments and features and aspects of various developments may be added to or substituted for other features or aspects of other developments in order to provide still further developments.

[0085] Accordingly, this disclosure includes all modifications and equivalents of the subject matter recited in the claims appended hereto as permitted by applicable law. Moreover, any combination of the above-described elements in all possible variations thereof is encompassed by the disclosure unless otherwise indicated herein or otherwise clearly contradicted by context.

List of reference numerals a angular deflection clearance * valve guide direction (actual, or current direction) * length of the valve guide * nominal valve guide direction (theoretical, at no deformation) valve guide 10A first valve guide 10B second valve guide 12 valve guide portion 13 second valve guide portion 14 mounting device 16 ball joint connection 17 inner ring of the mounting device 18 guide tube 19 outer ring of the mounting device first end 22 second end 24 second mounting device 26 second ball joint connection 27 inner ring of the second mounting device 28 axial fastening means 29 outer ring of the second mounting device dampening device valve 100A first valve 100B second valve valve stem valve head valve assembly 210 valve seat 220 valve bridge 230 valve spring 300 cylinder head 310 cylinder head mount thickness 320 cylinder head deformation 400 piston engine

Claims

Claims What is claimed is: 1. A valve guide (10) for a cylinder head (300) of a piston engine (400), the valve guide (10) comprising a valve guide portion (12), configured to guide a valve (100) along a valve guide direction (D), and at least one mounting device (14), characterized in that the mounting device (14) is configured to allow an angular deflection (a) of the valve guide portion (12) relative to a nominal valve guide direction (N).
2. The valve guide (10) according to claim 1, wherein the mounting device (14) comprises a joint connection, preferably a ball joint connection (16).
3. The valve guide (10) according to any of the previous claims, wherein the angular deflection (a) comprises a range of 0.01 to 0.50.
4. The valve guide (10) according to any of the previous claims, wherein the guided portion (12) comprises a guide tube (18) having a first end (20) and a second end (22), wherein the mounting device (14) is provided on the first end (20).
5. The valve guide (10) according to claim 4, wherein the guided portion (12) comprises a second mounting device (24), provided on its second end (22).
6. The valve guide (10) according to claim 5, wherein the second mounting device (24) comprises a second joint connection, preferably a second ball joint connection (26).
7. The valve guide (10) according to any of the previous claims, further comprising axial fastening means (28) for securing the first and/or second mounting devices (14, 24), wherein the first and second mounting devices (14, 24) are arranged in a fixed/floating, X-, or 0-bearing configuration.
8. The valve guide (10) according to any of the previous claims, further comprising a dampening device (30) configured to dampen fluctuations of the valve guide portion (12) about the angular deflection (a).
9. The valve guide (10) according to any of the previous claims, wherein the guided portion (12) has a length (L) which is shorter than a cylinder head mount thickness (310).
10. A valve (100) suitable for use in a valve guide (10) according to any of the previous claims 1-9, the valve (100) comprising a valve stem (110) and a valve head (120).
11. A valve assembly (200) for a cylinder head (300) of a piston engine (400), comprising a valve guide (10) according to any of the previous claims 1-9 and a valve (100) according to claim 10.
12. The valve assembly (200) of claim 11, further comprising a valve seat (210), wherein the valve head (120) and/or the valve seat (210) are configured such that the angular deflection (a) of the valve (100) is accommodated such that the valve head (120) and the valve seat (210) can be brought together in a sealed manner.
13. The valve assembly (200) according to claims 11 or 12, comprising the valve (100) as a first valve (100A) and the first valve guide (10) as a first valve guide (10), further comprising a second valve (100B) and a second valve guide (20), and a valve bridge (220) mechanically coupling the first and second valves (100A; 100B).