LUBRICATION DEVICE, CYLINDER HEAD COVER, CYLINDER HEAD COMPONENT, SYSTEM THEREOF, AND OIL LUBRICATED MACHINE

Technical Field

The present disclosure pertains to a lubrication device for an oil lubricated machine, preferably a reciprocating internal combustion engine, more preferably a stationary gas engine. The present disclosure also pertains to a cylinder head cover, and a cylinder head component comprising such lubrication devices. The present disclosure further pertains to a system of such a cylinder head cover and a cylinder head component. Furthermore, the present disclosure pertains to an oil lubricated machine.

In many oil lubricated machine applications, components of cylinder heads are merely lubricated by oil dust inside of the cylinder head cover. Such components typically include, but are not limited to, valve guides, valve rocker arms, and valve springs. In such applications, lubrication occurs when oil dust particles, in the shape of oil droplets, attach to surfaces of moving parts.

As for most applications, the available oil dust is limited, and only a small fraction of available oil dust particles attaches to surfaces in need of lubrication. In some instances, and especially during long operation durations, cylinder head components do not receive enough lubrication oil. Consequently, wear on these components increases, which is detrimental to the operation safety, maintenance costs, and fuel efficiency.

The lubrication device for an oil lubricated machine, the cylinder head cover, the cylinder head component, the system of a cylinder head cover and the cylinder head component, as well as the oil lubricated machine of the present disclosure solve one or more problems set forth above. Summary of the Invention

Starting from the prior art, it is an objective to provide a simple, cost-effective, and reliably operating lubrication device for an oil lubricated machine, in particular for a reciprocating internal combustion engine, ICE, more specifically, for a stationary gas engine.

This objective is solved by means of a lubrication device for an oil lubricated machine with the features of claim 1, a cylinder head cover comprising such lubrication device with the features of claim 10, a cylinder head component comprising such lubrication device with the features of claim 12, a system of such a cylinder head cover and a cylinder head component with the features of claim 14, and an oil lubricated machine with the features of claim 15. Preferred embodiments are set forth in the present specification, the Figures as well as the dependent claims.

Accordingly, a lubrication device for an oil lubricated machine is provided. The lubrication device comprises an oil collection surface, configured to collect oil dust, and an oil accumulation site, configured to promote an oil flow from the collected oil dust.

Furthermore, a cylinder head cover is provided, comprising a lubrication device according to the present disclosure.

In addition, a cylinder head component is provided, comprising a lubrication device according to the present disclosure.

Moreover, a system of a cylinder head cover according to the present disclosure, and a cylinder head component according to the present disclosure is provided.

Further, an oil lubricated machine, preferably an internal combustion engine, ICE, in particular a gas engine, is provided, comprising at least one cylinder head cover according to the present disclosure and/or at least one cylinder head component according to the present disclosure. of the Drawings

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:

Fig. 1 schematically shows a partial view of a cylinder head of an oil lubricated machine according to the state of the art;

Fig. 2 schematically shows an oil lubrication device according to a first embodiment of the present disclosure;

Fig. 3 schematically shows an oil lubrication device according to a development of the present disclosure;

Fig. 4 schematically shows an oil lubrication device according to a further development of the present disclosure;

Fig. 5 schematically shows an oil lubrication device according to a second embodiment of the present disclosure;

Fig. 6 schematically shows a cylinder head cover comprising an oil lubrication device according to the first embodiment of the present disclosure;

Fig. 7 schematically shows a cylinder head component comprising an oil lubrication device according to a second embodiment of the present disclosure; and

Fig. 8 schematically shows a system of a cylinder head of the present disclosure and a cylinder head component according to the present disclosure.

Detailed Description of Preferred Embodiments

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.

The present disclosure is generally directed towards lubrication applications for lubricating cylinder head components such as valve guides and other moving parts. In particular, the present disclosure is directed towards applications in reciprocating internal combustion engines using sump oil lubrication and sump oil dust for lubricating cylinder head components. Further, the present disclosure may be directed towards lubrication applications in gas engines, in particular stationary gas engines.

In Figure 1, a cylinder head as it is known from the state of the art is shown schematically in a partial side view. Accordingly, a cylinder head cover 200 is shown. On the inside of the cover 200, oil dust 110 is present. Such oil dust 110 may for example stem from an oil sump which is stirred up by moving parts of an engine (not shown in Figure 1). This oil dust 110 attaches on all inner surfaces of the cylinder head cover 200, including its inner walls and surfaces of the piston valve 310, the piston valve rocker arm 320 and the piston valve spring 330. As these components are moving parts, they need lubrication during operation.

However, such oil dust lubrication alone bears the risk of insufficient lubrication during long operation times as they are frequently observed in stationary engines. Further, due to the harsh environment within the cylinder head, the possibility of adding measures to improve lubrication within the cylinder head is limited.

In view thereof, improved lubrication devices for an oil lubricated machine are needed for optimal lubrication of moving parts within the cylinder head cover.

In Figure 2, a lubrication device 10 according to a first embodiment is schematically shown in a side view. The lubrication device 10 is configured for an oil lubricated machine. The lubrication device 10 comprises an oil collection surface 12, configured to collect oil dust 110. The lubrication device 10 further comprises an oil accumulation site 14, configured to promote an oil flow 18 from the oil dust 110 that is collected on the oil collection surface 12.

In the sense of the present disclosure, a lubrication device 10 may be understood as a passive oil collection and oil delivery device. Oil collection is achieved by passively collecting oil dust using the increased capture cross-section provided by the oil collection surface. Likewise, the oil flow is achieved passively by utilizing primarily gravitational forces. The latter definitions refer to a state in which oil dust is present due to engine operation.

To this end, the oil collection surface 12 may be any surface configured to provide an oil reservoir stemming from the oil dust 110 collected from the adjacent gas phase. Further, an oil accumulation site 14 may be any shape or form suitable for triggering an oil flow 18 based on an accumulation of collected oil dust 110.

In the context of the present disclosure, the term oil film 16 refers to an uninterrupted film of oil spreading across a surface. The term oil flow 18 refers to the actual lubricant oil flow between the lubrication device 10 and the component to be lubricated. Hence, the oil flow 18 may comprise, or consist of, an oil film 16. However, if for example a gap between the lubrication device 10 and the component to be lubricated is present, the oil flow 18 may have the form of discrete oil drops. Further, while the term droplet is used as a diminutive form of ‘drop’, both terms are to be understood interchangeably.

The oil collection surface 12 of the lubrication device 10 may be configured to collect oil dust 110 as an oil film 16 thereon. To this end, the oil collection surface 12 may have a surface with a suitable surface quality such that deposited oil droplets from the oil dust 110 may spread out, coalesce, and form an oil film 16. The oil collection surface 12 of the lubrication device 10 may be substantially flat, curved, and/or angled.

As shown in the embodiment of Figure 2, the lubrication device 10 may comprise a straight edge 20 having a thickness 22, wherein the oil accumulation site 14 may be configured as a local interruption of the straight edge 20, comprising at least one comer 24. More specifically, the oil accumulation site 14 may comprise a protrusion. By providing such a local interruption of the straight edge, any oil creeping downwards, towards a state of lower potential energy, is stopped by the at least one edge due to the surface tension of the oil.

At the oil collection surface 12, surface tension forces in the oil film are in balance with the gravitational force. However, when the oil film 16 reaches the oil accumulation site 14, the oil film is locally stopped, and a curved liquid-vapor interface begins to form. With continued oil influx, a hanging drop forms, with increasing drop weight. At a given stage, gravity overcomes the surface tension, and the drop begins to fall and eventually detaches. One increment of an oil flow 18 is delivered. Hence, the oil accumulation site 14 may be configured to provide the oil flow 18 in the shape of oil drops.

Drop formation, drop fall, and drop detachment depend on material properties and can be predicted using the dimensionless parameters Bond number Bo and Reynolds number Re, which are defined as: and

Ra

Re = — (2) h ² wherein R is the drop radius, p the liquid density, o the surface tension, and rj the liquid viscosity.

The static aspects of the droplet formation, as well as the period of droplet evolution leading to droplet detachment are in general considered to be a function of the dimensionless Bo and Re numbers, c.f. Eggers, J., Non linear dynamics and breakup of free-surface flows, Rev. Mod. Phys., 69(3), 865-929, 1997.

To adjust the lubrication intensity, the oil accumulation site 14 may be configured such that under nominal operation conditions, the oil flow 18 comprises a predetermined drop frequency.

Further, at the oil accumulation site 14, which may have the shape of a protrusion, an oil reservoir is provided into which the oil film creeps and accumulates. Such a protrusion may extend in the plane of the oil collection surface.

Further, the lubrication device 10 may be configured to be attachable to a cylinder head cover, wherein the oil accumulation site 14 may be configured to provide an oil flow to a cylinder head component, in particular a piston valve, a piston valve rocker arm, and/or a piston valve spring (not shown in Figure 2).

According to a development not shown in Figure 2, the lubrication device 10 may further comprise a plurality of oil accumulation sites 14, preferably four oil accumulation sites 14, wherein each oil accumulation site 14 may be configured to provide an oil flow 18 to a dedicated cylinder head component, in particular piston valve, a piston valve rocker arm, and/or a piston valve spring (not shown in Figure 2).

In Figure 3, a further development of the lubrication device 10 of the present disclosure is shown. The lubrication device 10 shown in Figure 3 differs from the lubrication device 10 shown in Figure 2 in that the oil accumulation site 14 may comprise a recess. The oil accumulation site 14 is configured as a local interruption of the straight edge 20, comprising at least one corner 24. However, the oil film may be accumulated on the inner region of the oil collection surface 12 rather than on a protruding region as shown in the embodiment of Figure 2. Also here, oil film accumulation is primarily driven by gravitational forces.

In Figure 4, a further development of the lubrication device 10 according to the present disclosure is shown. The lubrication device 10 shown in Figure 4 differs from the lubrication devices 10 shown in Figures 2 and 3 in that the oil accumulation site 14 may comprise a bore, preferably a groove. In the development shown in Figure 4, the oil accumulation site 14 is configured as local interruption of the straight edge 20 in the direction of its thickness 22. In this case, the oil film 16 may be accumulated in the groove. In this case, oil film accumulation is driven by gravitational forces and capillary forces, allowing a stronger accumulation effect.

In Figure 5, a lubrication device 10 according to a second embodiment is shown schematically. The lubrication device 10 is suitable for an oil lubricated machine, in particular a reciprocating internal combustion engine, for example a gas engine. The lubrication device 10 according to the second embodiment also comprises an oil collection surface 12, configured to collect oil dust 110. Further, the lubrication device 10 also comprises an oil accumulation site 14, configured to promote an oil flow 18 from the collected oil dust 110. The same definitions provided in the context of the first embodiment also apply.

Further, the oil collection surface 12 of the lubrication device 10 may further be configured to collect oil dust 110 as an oil film 16 thereon, as discussed in the context of the first embodiment.

The second embodiment of the lubrication device 10 as shown in Figure 5 differs from the first embodiment of the lubrication devices 10 as explained by the various developments of Figures 2-4 in that the oil accumulation site 14 may be configured to be connected to a cylinder head component 300. Accordingly, the lubrication device 10 may be configured such that the oil flow 18 may extend from the oil collection surface 12 via the oil accumulation site 14 to the cylinder head component 300. In other words, the oil flow 18 may have the shape of an oil film flow.

To this end, the oil accumulation site 14 may extend over the entire width of the lubrication device 10. The oil collection surface 12 may comprise a flat surface which may be attached directly to the cylinder head component 300 along the oil accumulation site 14. In further developments of the second embodiment, not shown in Figure 5, the oil collection surface 12 may also comprise a curved, and/or angled surface which is configured to be attachable to the cylinder head component 300.

In Figure 6, a cylinder head cover 100 is shown in a schematic cross-sectional view. The cylinder head cover 200 comprises a lubrication device 10 according to a first embodiment. More specifically, the lubrication device 10 shown in Figure 6 corresponds to the lubrication device as discussed in the context of Figure 2.

The same principles and definitions provided in the context of the lubrication device according to the first embodiment also apply to the cylinder head cover 200 of Figure 6. As can be seen from the illustration, oil dust 110 present in the inner volume of the cylinder head cover 200 may accumulate on the oil collection surface 12, acting as a cross-section enhancement for capturing oil dust 110 inside the cylinder head cover 200.

After being collected on the oil collection surface 12, collected oil dust 110 travels towards the bottom due to gravitation and accumulates at the oil accumulation site 14. The actual lubricant oil flow 18, flowing from the lubrication device 10 to the cylinder head component 300, occurs at the oil accumulation site 14, which promotes said oil flow 18 by releasing an accumulated oil film 16 stemming from the collected oil dust 110. According to the present example, the oil flow 18 may have the form of oil drops.

Further, the lubrication device 10 may be attached to a top 210 of the cylinder head cover 200, wherein the oil accumulation site 14 may be configured to provide, in a mounted state, an oil flow 18 in the form of oil drops to a cylinder head component 300, in particular a piston valve 310, a piston valve rocker arm, and/or a piston valve spring (not shown in Figure 6).

According to an embodiment not shown in Figure 6, the cylinder head cover 200 may further comprise a plurality of lubrication devices 10, preferably four. It will be appreciated by the person skilled in the art that each of the plurality of lubrication devices 10 may be configured to provide, in a mounted state, an oil flow 18 in the form of oil droplets to an adjacent cylinder head component 300, respectively.

In Figure 7, a cylinder head component 300 is shown schematically, comprising a lubrication device 10 according to the second embodiment of the present disclosure. According to the shown illustration, the lubrication device 10 is mounted to a piston valve rocker arm 320 which is part of the cylinder head component 300.

To this end, the same explanations, principles, and definition provided for the second embodiment of the lubrication device 10 apply, as set forth in the context of Figure 5 above. Accordingly, the oil accumulation site 14 may be configured to be connected to a cylinder head component 300, such that the oil flow 18 may be established from the oil collection surface 12 via the oil accumulation site 14 to the cylinder head component 300. In other words, the oil flow 18 may remain an oil film flow.

As can be seen from Figure 7, the oil dust 110 collected on the oil collection surface 12 travels downward to the piston valve 310 via the oil accumulation site 14 and the piston valve rocker arm 320 connected to the oil accumulation site 14 of the lubrication device. Hence, due to the increased capture cross-section for oil dust 110, provided by the oil collection surface 12 of the lubrication device 10, an increased oil flow 18 may be established to the piston valve 310. Thereby, the lubrication of the piston valve 310 and all cylinder head components 300 subjected to the oil flow 18 may receive more lubricant oil.

In Figure 8, a system of a cylinder head cover 200 in the sense of the present disclosure, and a cylinder head component in the sense of the present disclosure is shown schematically.

In other words, a system of a cylinder head cover 200 comprising a lubrication device according to the first embodiment and a cylinder head component comprising a lubrication device according to the second embodiment is shown. More specifically, the cylinder head cover 200 may comprise a lubrication device 10 as shown in Figure 2 of the present disclosure. Likewise, the cylinder head component 300 may comprise a lubrication device 10 as shown in Figure 5 of the present disclosure.

The system of a cylinder head cover 200 and the cylinder head component 300 may be part of an oil lubricated machine 100. The oil lubricated machine may be a reciprocating internal combustion engine, in particular a gas engine. Further, the system may be used in an oil lubricated machine using an oil sump.

With the disclosed system of a cylinder head cover and the cylinder head component, oil lubrication of the cylinder head component 300 may be maximized.

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.

This is in particular the case with respect to the following optional features which may be combined with some or all developments, items, and all features mentioned in any technically feasible combination. As an example, the lubrication device may be suitable for a reciprocating engine of the internal combustion engine type, in particular a gas engine. Further, the lubrication device may be suitable for a stationary gas engine. The lubrication device may be installed within one or more cylinder heads of the oil lubricated machine. Further, variations, combinations, and multiplications of lubrication devices may also be encompassed by the present disclosure.

A lubrication device for an oil lubricated machine may be provided, the lubrication device comprising an oil collection surface, configured to collect oil dust, and an oil accumulation site, configured to promote an oil flow from the collected oil dust. Pertaining to the definitions of the terms collection surface, oil accumulation site, and others, it is also referred to the Figure’s description.

Providing such a lubrication device has the advantage of passively increasing an oil flow to a cylinder head component in need of lubrication. Thereby, a cost-effective, easy to install, maintain, retrofit, and safely operable lubrication device may be provided. According to a further development, the oil collection surface may be configured to collect oil dust as an oil film thereon. For example, the oil collection surface may have a sufficiently small surface roughness such that an oil film may form. The person skilled in the art will appreciate that oil properties are dependent on temperature, impurities, specifications, and other factors. Additionally, oil dust properties may vary drastically during operation of an oil lubricated machine. To this end, it is referred to a hypothetical condition under nominal operation of the oil lubricated engine. Whether the oil collection surface is suitable for collecting oil dust as an oil film may be identified without undue burden by means of simple, straightforward experiments.

Providing an oil collection surface configured to collect oil dust as an oil film has the advantage that the entity of collected oil on the surface can be transported away therefrom. When an oil film is established, oil will start creeping towards points of lower potential energy due to gravitational forces. This may be used for the oil flow and ultimately for lubricating the cylinder head components in need of lubrication.

According to a preferred embodiment, the lubrication device may further comprise a straight edge having a thickness, wherein the oil accumulation site is confirmed as a local interruption of the straight edge, comprising at least one comer. Providing such a local interruption of the straight edge, by comprising at least one edge, an oil flow creeping towards a lower energy state is stopped due to surface tension of the oil. Consequently, oil starts accumulating at this location, a curved liquid-gas interface forms.

Thereby, an oil reservoir builds up at a predefined position, suitable for lubricating an adjacent cylinder head component.

According to a further development, the oil accumulation site may comprise a protrusion, a recess, a bore, and/or a groove, wherein the oil accumulation site may be configured to provide the oil flow in the shape of oil drops. When the oil film builds up at the oil accumulation site, an oil droplet begins to grow. Ultimately, an oil drop detaches from the oil accumulation site and falls towards a predefined spot in the oil lubricated machine, for example towards a cylinder head component to be lubricated such as a piston valve, a piston valve rocker arm and/or a piston valve spring. Splashing on said component, the oil drop delivers a volume of lubricant oil. Hence, one increment of the oil flow is delivered. Comprising a bore and/or a groove has the advantage that in addition to gravitational force, capillary forces may help with the accumulation of oil at the accumulation site.

According to a further development, the oil accumulation site may be configured such that under nominal operation conditions, the oil flow comprises a predetermined drop frequency. Thereby, the lubrication of a component to be lubricated may be set to a predetermined rate. The oil flow may for example comprise a drop frequency of 1 drop per second; 1 Hz.

According to a preferred embodiment, the lubrication device may be configured to be attachable to a cylinder head cover, wherein the oil accumulation site may be configured to provide an oil flow to a cylinder head component, in particular a piston valve, a piston valve rocker arm, and/or a piston valve spring. According to this embodiment, cylinder inclinations, cylinder vibrations, and forces acting upon the cylinder during operation of the oil lubricated machine may be factored in. Thereby, a reliable lubrication of the cylinder head components to be lubricated may be achieved.

According to a preferred embodiment, the lubrication device may further comprise a plurality of oil accumulation sites, preferably four oil accumulation sites, wherein each oil accumulation site may be configured to provide an oil flow to a dedicated cylinder head component, in particular a piston valve, a piston valve rocker arm, and/or a piston valve spring.

According to this embodiment, the lubrication device may also comprise a plurality of oil collection surfaces. Providing the plurality of oil collection surfaces and/or oil accumulation sites has the advantage of being able to deliver an oil flow to several cylinder head components to be lubricated.

Thereby, safe operation of the oil lubricated machine can be achieved and excessive wear due to insufficient lubrication can be avoided.

According to an alternative embodiment of the lubrication device, the lubrication device may be configured to be connected to a cylinder head component, such that the oil flow streams from the oil collection surface via the oil accumulation site towards the cylinder head component.

According to this embodiment, the oil flow may purely be an oil film flow. This has the advantage that the oil flow can be predicted more precisely, since no droplet phenomena need to be considered. Oil inherent or environmentally inflicted changes are less likely to influence the oil flow. Thereby, the oil lubrication may be achieved in a more stable, predicable manner.

According to a preferred development of this embodiment, the oil collection surface may comprise a flat, curved, and/or angled surface, configured to be attached to the cylinder head component to be lubricated. Thereby, the capture cross-section for capturing air-borne oil dust may be increased and customized to a given environment inside the cylinder head cover.

A cylinder head cover may be provided, comprising a lubrication device according to the present disclosure. The lubrication device may be a lubrication device according to the first embodiment according to the present disclosure. The same explanations, definitions, and advantages provided herein with reference to the lubrication device according to the first embodiment also apply to the cylinder head cover. Providing such a cylinder head cover has the advantage that any cylinder may easily be retrofitted with a lubrication device by replacing a conventional cylinder cover with the cylinder cover according to the present disclosure.

According to a preferred development, the lubrication device may be attached to a cylinder head cover top, wherein the oil accumulation site may be configured to provide, in a mounted state of the cylinder head cover, an oil flow in the form of oil drops to a cylinder head component. Thereby, a reliable, cost-effective, and easy to maintain and operate lubrication device may be achieved.

According to a preferred development, the cylinder head cover may further comprise a plurality of lubrication devices, preferably four. Thereby, a plurality of cylinder head components may be lubricated simultaneously.

A cylinder head component may be provided, comprising a lubrication device according to the present disclosure. The lubrication device may be a lubrication device according to the second embodiment according to the present disclosure. The same explanations, definitions, and advantages provided herein with reference to the lubrication device according to the second embodiment also apply to the cylinder head cover. Providing such a cylinder head component has the advantage that any cylinder may easily be retrofitted with a lubrication device by replacing a conventional cylinder head component with the cylinder head component according to the present disclosure.

According to a preferred development, the cylinder head component may further comprise a piston valve, preferably wherein the piston valve comprises a valve rocker arm, and a piston valve spring. The lubrication device may be attached to the piston valve, and/or the piston valve rocker arm. Thereby, a short oil flow travel path from the oil collection surface to the valve component to be lubricated may be achieved.

A system of a cylinder head cover in the sense of the present disclosure, and a cylinder head component in the sense of the present disclosure is provided. In other words, a system of a cylinder head cover comprising a lubrication device according to the first embodiment and a cylinder head component comprising a lubrication device according to the second embodiment is provided.

The system of a cylinder head cover and the cylinder head component may be part of an oil lubricated machine. Further, the system may be used in an oil lubricated machine using an oil sump. With the disclosed system of a cylinder head cover and the cylinder head component, oil lubrication of the cylinder head component may be maximized.

An oil lubricated machine is provided, preferably a reciprocating internal combustion engine, in particular a stationary gas engine, comprising at least one cylinder head cover according to the present disclosure and/or a cylinder head component according to the present disclosure.

With the disclosed oil lubricated machine, oil lubrication of the cylinder head component may be maximized, and long term machine operation may be possible.

Industrial Applicability

With reference to the Figures, a lubrication device for an oil lubricated machine, a cylinder head cover, a a cylinder head component, a system of such a cylinder head cover and a cylinder head component and an oil lubricated machine are applicable in any suitable combustion engine, for example internal combustion engines ICEs for gaseous fuels.

In practice, said products and 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.

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

Referring to Figure 2, there is a development shown disclosing a lubrication device for an oil lubricated machine is provided. The lubrication device comprises an oil collection surface, configured to collect oil dust, and an oil accumulation site, configured to promote an oil flow from the collected oil dust. One skilled in the art will expect that various developments of the present disclosure will have an improved simplicity, necessitating less maintenance and increased operation reliability for lubrication systems.

The same advantages apply to the remaining figures, in particular to the cylinder head cover, the cylinder head component, the system thereof and the oil lubricated machine comprising such a lubrication device.

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.

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.

Recitation of ranges of values herein are 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.

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.

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.