Internal combustion engine and cylinder head configured for in-cylinder pressure sensor

Abstract

An internal combustion engine includes a cylinder head configured for a cylinder of the internal combustion engine. The cylinder head includes a sensor port having a housing portion configured to receive an in-cylinder pressure sensor. The sensor port includes a channel portion extending from the housing portion to a combustion side of the cylinder head to fluidly connect the in-cylinder pressure sensor with the combustion chamber.

Description

[0001] Cross-references to related applications This application claims priority on the filing dates of U.S. Provisional Application Serial No. 63 / 691,639, filed September 6, 2024, and U.S. Provisional Application Serial No. 63 / 783,370, filed April 4, 2025, both of which are incorporated herein by reference in their entirety. Technical Field

[0002] This invention relates to internal combustion engines, and more particularly to internal combustion engines and cylinder heads configured for in-cylinder pressure sensors. Background Technology

[0003] An internal combustion engine may include a cylinder head mounted to an engine block. The engine block defines a plurality of cylinders, each forming a combustion chamber to receive fuel and charge flow (air or an air-fuel mixture) through one or more intake valve openings in the cylinder head (such as for a four-stroke engine) or through ports in the cylinder liner (such as for a two-stroke engine). The fuel and charge flow is burned in the combustion chamber to drive a piston located in the cylinder.

[0004] In-cylinder pressure sensors are used to measure pressure changes within the combustion chamber during a combustion cycle. This data can be used to calculate many parameters that control engine operation. Existing methods for mounting in-cylinder pressure sensors have many drawbacks and shortcomings in terms of ease of manufacture, reliability, ability to accurately sense in-cylinder pressure conditions, accessibility for maintenance and upkeep of the sensor and nearby engine components, compatibility across various engine platforms, and / or compatibility with different types of in-cylinder pressure sensors. Therefore, further improvements are desired in this field. Summary of the Invention

[0005] This disclosure relates to an internal combustion engine and a cylinder head configured to receive an in-cylinder pressure sensor that senses and measures pressure changes in the combustion chamber of the internal combustion engine. The sensor port is configured to receive the in-cylinder pressure sensor and fluidly connect the in-cylinder pressure sensor to the combustion chamber.

[0006] In embodiments of this disclosure, an internal combustion engine configured for in-cylinder pressure sensing is provided. The internal combustion engine includes at least one cylinder, which includes a combustion chamber for receiving charge flow and fuel for combustion within the combustion chamber. The internal combustion engine also includes a cylinder head mounted to the at least one cylinder. The cylinder head includes an opening for providing charge flow to the combustion chamber or receiving exhaust flow from the combustion chamber through the opening. The cylinder head also includes: a valve relief cutout extending around the opening; and a sensor port for receiving an in-cylinder pressure sensor in fluid communication with the combustion chamber.

[0007] In one embodiment, the sensor port includes a housing portion for housing the in-cylinder pressure sensor and a passage portion extending from the valve pressure relief cutout to the housing portion to fluidly connect the in-cylinder pressure sensor housed in the housing portion with the combustion chamber. In another embodiment, the sensor port includes a housing portion for housing the in-cylinder pressure sensor and a passage portion extending from the cylinder to the housing portion to fluidly connect the in-cylinder pressure sensor housed in the housing portion with the combustion chamber.

[0008] In an embodiment, a cylinder head for a cylinder of an internal combustion engine is provided. The cylinder head includes a cylinder head body including a combustion side facing the cylinder. The cylinder head body further includes a sensor port. The sensor port includes a housing portion configured to house an in-cylinder pressure sensor, a first passage portion extending from the housing portion into the cylinder head body, and at least one second passage portion extending non-collinearly with the first passage portion to the combustion side of the cylinder head.

[0009] In an embodiment, a cylinder head for a cylinder of an internal combustion engine is provided. The cylinder head includes a cylinder head body including a combustion side facing the cylinder. The cylinder head body further includes a sensor port for an in-cylinder pressure sensor. The sensor port includes a housing portion configured to house the in-cylinder pressure sensor and a passage portion extending from the housing portion to the combustion side of the cylinder head. The passage portion is configured to attenuate acoustic ringing detected by the in-cylinder pressure sensor due to resonance in the passage portion and / or increase a resonance frequency.

[0010] This Summary is provided to introduce some concepts in a simplified form that are further described below in the illustrative embodiments. This Summary is not intended to identify key features or essential features of the claimed subject matter, nor is it intended to be used to limit the scope of the claimed subject matter. Additional embodiments, forms, objects, features, advantages, aspects, and benefits will become apparent from the following description and drawings.

[0011] The present invention also includes the following technical solutions.

[0012] Technical Solution 1. An internal combustion engine configured for in-cylinder pressure sensing, the internal combustion engine comprising: at least one cylinder including a combustion chamber to receive a charge flow and fuel for combustion; and a cylinder head mounted to the at least one cylinder, the cylinder head including an opening to provide a charge flow to the combustion chamber or receive an exhaust flow from the combustion chamber, the cylinder head including: a valve relief cut extending around the opening; and a sensor port to house an in-cylinder pressure sensor in fluid communication with the combustion chamber, the sensor port including: a housing portion to house the in-cylinder pressure sensor; and a channel portion extending from the valve relief cut to the housing portion to fluidly connect the in-cylinder pressure sensor housed in the housing portion with the combustion chamber.

[0013] Technical Solution 2. The internal combustion engine of Technical Solution 1, wherein the opening includes: a valve seat insert mounted in the cylinder head; and the valve relief cut extends from the valve seat insert toward the combustion chamber, the channel portion opening to the combustion chamber at the valve relief cut.

[0014] Technical Solution 3. The internal combustion engine of Technical Solution 2, wherein the valve relief cut flares outwardly from the valve seat insert toward the combustion chamber.

[0015] Technical Solution 4. The internal combustion engine of Technical Solution 1, further comprising a manifold mounted to the cylinder head, the manifold configured to provide the charge flow to the cylinder head or receive the exhaust flow from the cylinder head.

[0016] Technical Solution 5. The internal combustion engine of Technical Solution 4, wherein the manifold includes: an end wall extending along the cylinder head; and a slot extending into the end wall around the sensor port, the slot providing access to the in-cylinder pressure sensor in the sensor port.

[0017] Technical Solution 6. The internal combustion engine of Technical Solution 5, further comprising a manifold gasket between the cylinder head and the manifold, wherein the manifold gasket includes a second slot aligned with the slot of the manifold.

[0018] Technical Solution 7. The internal combustion engine of Technical Solution 6, wherein the manifold gasket includes a cross member aligned with the end wall of the manifold, the cross member extending through the second slot.

[0019] TECHNICAL SOLUTION 8. The internal combustion engine of TECHNICAL SOLUTION 1, wherein the passage portion of the sensor port comprises: a first passage portion extending from the housing portion toward the combustion chamber; and a second passage portion oriented obliquely relative to the first passage portion, the second passage portion extending from the first passage portion to the valve relief cut.

[0020] TECHNICAL SOLUTION 9. The internal combustion engine of TECHNICAL SOLUTION 8, wherein: the first passage portion comprises a first cross-sectional area; and the second passage portion comprises a second cross-sectional area that is less than the first cross-sectional area.

[0021] TECHNICAL SOLUTION 10. The internal combustion engine of TECHNICAL SOLUTION 8, wherein the housing portion is axially aligned with the first passage portion.

[0022] TECHNICAL SOLUTION 11. A cylinder head for a cylinder of an internal combustion engine, the cylinder head comprising: a cylinder head body comprising a combustion side toward the cylinder, the cylinder head body further comprising a sensor port for an in-cylinder pressure sensor, the sensor port comprising: a housing portion configured to house the in-cylinder pressure sensor; a first passage portion extending from the housing portion into the cylinder head; and at least one second passage portion extending to the combustion side of the cylinder head non-collinearly with the first passage portion.

[0023] TECHNICAL SOLUTION 12. The cylinder head of TECHNICAL SOLUTION 11, wherein the first passage portion is collinear with the housing portion.

[0024] TECHNICAL SOLUTION 13. The cylinder head of TECHNICAL SOLUTION 11, wherein the first passage portion is straight and the at least one second passage portion is straight.

[0025] TECHNICAL SOLUTION 14. The cylinder head of TECHNICAL SOLUTION 11, wherein the first passage portion is longer than the at least one second passage portion.

[0026] TECHNICAL SOLUTION 15. The cylinder head of TECHNICAL SOLUTION 11, wherein: the first passage portion comprises a first cross-sectional dimension; and the at least one second passage portion comprises a second cross-sectional dimension that is less than the first cross-sectional dimension.

[0027] Technical Solution 16. The cylinder head of Technical Solution 11, wherein: the first passage portion extends from the housing portion to a spherical end wall; and the at least one second passage portion intersects the spherical end wall.

[0028] Technical Solution 17. The cylinder head of Technical Solution 11, wherein: the combustion side of the cylinder head includes a valve blowdown cutout around an opening in the combustion side of the cylinder head; and the at least one second passage portion opens over the valve blowdown cutout.

[0029] Technical Solution 18. The cylinder head of Technical Solution 11, wherein: the cylinder head body includes a side wall to which a manifold is mounted; and the housing portion of the sensor port opens at the side wall of the cylinder head body.

[0030] Technical Solution 19. The cylinder head of Technical Solution 11, wherein: the first passage portion and the at least one second passage portion each include a circular cross-section; and a diameter of the first passage portion is greater than a diameter of the at least one second passage portion.

[0031] Technical Solution 20. The cylinder head of Technical Solution 17, wherein the at least one opening is part of an intake port formed by the cylinder head.

[0032] Technical Solution 21. A cylinder head for a cylinder of an internal combustion engine, the cylinder head comprising: a cylinder head body including a combustion side toward the cylinder, the cylinder head body further including a sensor port for an in-cylinder pressure sensor, the sensor port including: a housing portion configured to house the in-cylinder pressure sensor; a passage portion extending from the housing portion to the combustion side of the cylinder head, wherein the passage portion is configured to attenuate acoustic ringing due to resonance in the passage portion.

[0033] Technical Solution 22. The cylinder head of Technical Solution 21, wherein the passage portion is a single passage extending from the housing portion to the combustion chamber.

[0034] Technical Solution 23. The cylinder head of Technical Solution 21, wherein the passage portion includes: a first passage portion extending from the housing portion into the cylinder head; and a second passage portion extending from the combustion side of the cylinder head into the cylinder head; and the first passage portion includes at least one transition passage portion connecting the first passage portion to the second passage portion, the first passage portion, the second passage portion, and the at least one transition passage portion are configured to attenuate acoustic ringing detected by the in-cylinder pressure sensor due to resonance in the passage portions.

[0035] Technical Solution 24. The cylinder head of Technical Solution 23, wherein: the first passage portion includes a first cross-sectional dimension; the second passage portion includes a second cross-sectional dimension; and a ratio of the second cross-sectional dimension to the first cross-sectional dimension is greater than 1.

[0036] Technical Solution 25. The cylinder head of Technical Solution 23, wherein: the first passage portion extends along a first axis and includes a first length along the first axis; the second portion extends along a second axis and includes a second length along the second axis; and a ratio of the first length to the second length is less than 1.

[0037] Technical Solution 26. The cylinder head of Technical Solution 23, wherein: the at least one transition passage portion extends along a first axis, the at least one transition passage portion includes a first cross-sectional dimension that tapers along the first axis; and the second passage portion extends along a second axis, the second passage portion includes a second cross-sectional dimension that tapers along the second axis.

[0038] Technical Solution 27. The cylinder head of Technical Solution 23, wherein the at least one transition passage portion includes: a first transition passage portion extending from the first passage portion toward the second passage portion; and a second transition passage portion extending from the first transition passage portion to the second passage portion.

[0039] Technical Solution 28. The cylinder head of Technical Solution 27, wherein: the second transition passage portion includes a first cross-sectional dimension; the second channel portion includes a second cross-sectional dimension; and a ratio of the second cross-sectional dimension to the first cross-sectional dimension is not equal to 1.

[0040] Technical Solution 29. The cylinder head of Technical Solution 28, wherein the first transition channel portion includes a third cross-sectional dimension that is greater than the first cross-sectional dimension.

[0041] Technical Solution 30. The cylinder head of Technical Solution 28, wherein the first transition channel portion includes a third cross-sectional dimension that is less than or equal to the first cross-sectional dimension.

[0042] Technical Solution 31. The cylinder head of Technical Solution 30, wherein the first channel portion includes a fourth cross-sectional dimension that is greater than the third cross-sectional dimension.

[0043] Technical Solution 32. The cylinder head of Technical Solution 30, wherein the first channel portion includes a fourth cross-sectional dimension that is less than or equal to the third cross-sectional dimension.

[0044] Technical Solution 33. The cylinder head of Technical Solution 23, wherein the housing portion, the first channel portion, and the at least one transition channel portion are collinear with one another.

[0045] Technical Solution 34. The cylinder head of Technical Solution 23, wherein the second channel portion is obliquely oriented relative to the at least one transition channel portion.

[0046] Technical Solution 35. The cylinder head of Technical Solution 23, wherein the second channel portion is collinear with the at least one transition channel portion.

[0047] Technical Solution 36. The cylinder head of Technical Solution 23, wherein the second channel portion is orthogonal to the at least one transition channel portion.

[0048] Technical Solution 37. The cylinder head of Technical Solution 23, wherein the second channel portion is offset from the at least one transition channel portion.

[0049] Technical Solution 38. The cylinder head of Technical Solution 21, wherein the channel portion includes at least one transition channel portion between the housing portion and a second channel portion, the second channel portion extending from the combustion side of the cylinder head, wherein: the at least one transition channel portion includes a first cross-sectional dimension that is less than a second cross-sectional dimension of the second channel portion; or the at least one transition channel portion includes a first length that is less than a second length of the second channel portion.

[0050] TECHNICAL SOLUTION 39. The cylinder head of TECHNICAL SOLUTION 38, wherein the first cross- sectional dimension is less than the second cross-sectional dimension, and the first length is less than the second length.

[0051] TECHNICAL SOLUTION 40. The cylinder head of TECHNICAL SOLUTION 21, wherein the passage portion includes at least one transition passage portion between the housing portion and a second passage portion, the second passage portion extending from the combustion side of the cylinder head, wherein: the at least one transition passage portion includes a tapered first cross-sectional dimension; or the second passage portion includes a tapered second cross-sectional dimension.

[0052] TECHNICAL SOLUTION 41. The cylinder head of TECHNICAL SOLUTION 40, wherein at least one of the at least one transition passage portion and the second passage portion is conical.

[0053] TECHNICAL SOLUTION 42. A cylinder head for a cylinder of an internal combustion engine, the cylinder head comprising: a cylinder head body including a combustion side toward the cylinder, the cylinder head body further including a sensor port for an in-cylinder pressure sensor, the sensor port including: a housing portion configured to house the in-cylinder pressure sensor; a passage portion extending from the housing portion to the combustion side of the cylinder head, wherein the passage portion is configured to increase a resonant frequency.

[0054] TECHNICAL SOLUTION 43. The cylinder head of TECHNICAL SOLUTION 42, comprising any one or combination of TECHNICAL SOLUTIONS 22 to 41. BRIEF DESCRIPTION OF DRAWINGS

[0055] Figure 1 is a schematic illustration of an internal combustion engine including a cylinder head and an in-cylinder pressure sensor according to an embodiment of the present disclosure.

[0056] Figure 2 is a cross-sectional view through a cylinder head and a cylinder of an internal combustion engine showing a sensor port for housing an in-cylinder pressure sensor according to an embodiment of the present disclosure. Figure 1

[0057] Figure 3 Figure 1

[0058] Figure 4 is another schematic cross-sectional view through a cylinder head of an internal combustion engine showing a sensor port and an intake valve according to an embodiment of the present disclosure. Figure 1 ​​​A schematic front view of a portion of the intake manifold of the cylinder head of an internal combustion engine.

[0059] Figure 5 It is an installable according to the embodiments of this disclosure. Figure 1 The cylinder head of an internal combustion engine and Figure 4 A schematic front view of a portion of the intake manifold gasket between the intake manifolds.

[0060] Figure 6 This is a schematic front view of a portion of the intake manifold gasket in another implementation scheme.

[0061] Figure 7 This is a schematic cross-sectional view further illustrating the sensor port and valve relief cutout.

[0062] Figure 8 Is it through Figure 1 Another schematic cross-sectional view of the cylinder head of an internal combustion engine, which shows a sensor port of another implementation.

[0063] Figure 9 Is it through Figure 1 Another schematic cross-sectional view of the cylinder head of an internal combustion engine, which shows a sensor port of another implementation.

[0064] Figure 10 Is it through Figure 1 Another schematic cross-sectional view of the cylinder head of an internal combustion engine, which shows a sensor port of another implementation. Detailed Implementation

[0065] To facilitate an understanding of the principles of the invention, reference will now be made to the embodiments shown in the accompanying drawings, and these embodiments will be described using specific language. However, it should be understood that this is not intended to limit the scope of the invention, and any modifications and further alterations to the illustrated embodiments that would normally occur to those skilled in the art, as well as any further applications of the principles of the invention shown herein, are contemplated.

[0066] refer to Figures 1 to 7 The internal combustion engine 10 is configured for in-cylinder pressure sensing. The internal combustion engine 10 includes at least one cylinder 12, which includes a combustion chamber 14 for receiving a charge flow 20 and fuel for combustion. The internal combustion engine 10 also includes a cylinder head 30 mounted to the at least one cylinder 12.

[0067] This document discloses sensor portions 60, 160, 160' configured to house and fluidly connect an in-cylinder pressure sensor 62 to a combustion chamber 14. Sensor ports 60, 160, 160' include housing portions 64, 164 for housing the in-cylinder pressure sensor 62 and channel portions 66, 166, 166' fluidly connecting the combustion chamber 14 to the housing portions 64, 164. The in-cylinder pressure sensor 62 measures pressure in the channel portions 66, 166, 166', thereby providing an indication of the pressure in the combustion chamber 14.

[0068] The pressure in combustion chamber 14 differs from the pressure in passage portions 66, 166, 166'. This is due to ringing or oscillation caused by resonance in passage portions 66, 166, 166' of sensor ports 60, 160, 160'. Passage portions 66, 166, 166' are configured to attenuate the ringing detected by in-cylinder pressure sensor 62 and increase the resonant frequency, such that the measurement of pressure in passage portions 66, 166, 166' by in-cylinder pressure sensor 62 provides an indication of the in-cylinder pressure in combustion chamber 14.

[0069] Channel portions 66, 166, 166' distinguish the acoustic frequencies of channel portions 66, 166, 166' from the signals detected by the in-cylinder pressure sensor 62. Channel portions 66, 166, 166' are configured such that the amplitude of pressure oscillations in channel portions 66, 166, 166' is sufficiently low, and the inherent frequency of pressure oscillations in channel portions 66, 166, 166' is sufficiently high to not interfere with the ability to measure frequencies indicative of combustion performance (such as knock, non-knock combustion, etc.).

[0070] In one embodiment, the cylinder head 30 includes an opening 42 for supplying an intake flow 20 to or receiving an exhaust flow from the combustion chamber 14 through the opening 42. The cylinder head 30 also includes a valve relief cutout 54 extending around the opening 42 and a sensor port 60 for receiving an in-cylinder pressure sensor 62 in fluid communication with the combustion chamber 14. The sensor port 60 includes: a housing portion 64 for receiving the in-cylinder pressure sensor 62; and a passage portion 66 extending from the valve relief cutout 54 to the housing portion 64 to fluidly connect the in-cylinder pressure sensor 62, housed in the housing portion 64, to the combustion chamber 14.

[0071] In one embodiment, a cylinder head 30 for a cylinder 12 of an internal combustion engine 10 is provided. The cylinder head 30 includes a cylinder head body 31, which includes a combustion side 44 facing the cylinder 12. The cylinder head body 31 also includes a sensor port 60 for receiving an in-cylinder pressure sensor 62. The sensor port 60 includes: a housing portion 64 configured to receive the in-cylinder pressure sensor 62; a first channel portion 68 extending from the housing portion 64 into the cylinder head 30; and at least one second channel portion 70 extending non-collinearly with the first channel portion 68 to the combustion side 44 of the cylinder head 30.

[0072] In one embodiment, a cylinder head 30 for a cylinder 12 of an internal combustion engine 10 is provided. The cylinder head 30 includes a cylinder head body 31, which includes a combustion side 44 facing the cylinder 12. The cylinder head body 31 also includes sensor ports 160, 160' for an in-cylinder pressure sensor 62. The sensor ports 160, 160' include: a housing portion 164 configured to receive the in-cylinder pressure sensor 62; and channel portions 166, 166' extending from the housing portion 164 to the combustion side 44 of the cylinder head 30. The channel portions 166, 166' are configured to attenuate acoustic frequencies caused by resonance in the channel portions 166, 166' and / or increase resonant frequencies.

[0073] Figures 1 to 7 Various aspects of an internal combustion engine 10 are shown. The internal combustion engine 10 includes a plurality of cylinders 12, each cylinder having a combustion chamber 14. Each combustion chamber 14 defines a longitudinal axis A1 along which a piston (not shown) reciprocates between a bottom dead center position and a top dead center position. A cylinder head 30 extends along one or more of the cylinders 12 and is respectively connected to an intake manifold 16. In an embodiment, the cylinder head 30 is configured to allow an intake flow 20 to enter the combustion chamber 14 and receive an exhaust flow from the combustion chamber 14. In other embodiments, intake ports and / or exhaust ports are disposed along the cylinder 12 through bushings.

[0074] In the illustrated embodiment, each cylinder head 30 includes at least one intake port 32 aligned with a corresponding combustion chamber in the combustion chamber 14. Each intake port 32 forms an opening 42 configured to allow an intake flow 20 into the connected combustion chamber 14 when the intake valve 38 is displaced from the valve seat 40 to the open position. Each cylinder head 30 includes at least one exhaust port 36 connected to the combustion chamber 14, configured to allow combustion products to escape from the combustion chamber 14. The cylinder head 30 is connected to an exhaust manifold 18 that receives exhaust gas from the combustion chamber 14 and provides an exhaust flow 22. The cylinder head 30 may also include a fuel injector port 34 and a fuel injector (not shown) housed in the fuel injector port 34, and an ignition port (not shown) for housing an igniter.

[0075] Engine 10 can be any type of engine, and in a particular embodiment, it is an internal combustion engine that burns any suitable fuel and includes a plurality of cylinders 12, each housing a piston. In a particular embodiment, engine 10 burns a liquid fuel such as diesel, a gaseous fuel such as natural gas, or any other suitable type of fuel. Engine 10 can be a dual-fuel engine capable of using more than one type of fuel at a time, or a single-fuel engine. In the illustrated embodiment, engine 10 includes eight cylinders 12 connected to cylinder head 30. However, any number of cylinders 12 can be used in engine 10. Engine 10 can be a twin-cylinder bank engine as shown in the illustrated embodiment, an inline engine with a single cylinder bank, or other configurations including a V-cylinder arrangement, a W-type engine, or any engine arrangement with one or more cylinders 12. Engine 10 is contemplated to be provided as part of a powertrain for operating equipment (not shown), but other applications are also contemplated and not excluded, such as for generator sets, vehicles, and marine applications.

[0076] Sensor port 60 includes a housing portion 64 and a channel portion 66, the channel portion providing fluid connection between combustion chamber 14 and in-cylinder pressure sensor 62 housed in housing portion 64 of sensor port 60. Channel portion 66 opens at the combustion side 44 of cylinder head body 31, such as at a valve relief cutout 54. In embodiments, valve relief cutout 54 is a chamfered or beveled surface in combustion side 44 of cylinder head 30 associated with valve seat 40, but embodiments without valve seat 40 and / or valve seat ring 56 are also conceivable. In embodiments, valve relief cutout extends outward toward combustion chamber 14, such as... Figure 7 As further shown.

[0077] The channel portion 66 may include multiple channel portions, such as a first channel portion 68 and at least one second channel portion 70 in the illustrated embodiment. The housing portion 64 and the first channel portion 68 extend from the sidewall 50 of the cylinder head body 31 into the cylinder head body 31 along a second longitudinal axis A2. In one embodiment, the housing portion 64 extends collinearly to the first channel portion 68 of the sensor port 60. At least one second channel portion 70 extends non-collinearly with the first channel portion 68 and extends along a third longitudinal axis A3 forming an angle B with the second longitudinal axis A2.

[0078] In one embodiment, the second channel portion 70 is inclined relative to the first channel portion 68. In other embodiments, the second channel portion 70 is orthogonal to the first channel portion 68, or two or more non-collinear second channel portions 70 are provided. In one embodiment, each channel portion 68, 70 is straight. However, non-straight configurations for one or both of the channel portions 68, 70 are not excluded.

[0079] In one embodiment, the first channel portion 68 includes a first cross-sectional area and / or dimension d1 orthogonal to the second longitudinal axis A2. The second channel portion 70 includes a second cross-sectional area and / or dimension d2 orthogonal to the third longitudinal axis A3. In another embodiment, the second cross-sectional area and / or dimension d2 is smaller than the first cross-sectional area and / or dimension d1. In embodiments where the cross-sections of the first channel portion 68 and the second channel portion 70 are circular, dimensions d1 and d2 are the diameters of the respective channel portions in the first channel portion 68 and the second channel portion 70. Other embodiments may envision the first channel portion 68 and / or the second channel portion 70 having non-circular cross-sections.

[0080] In another embodiment, the second cross-sectional area and / or size d2 is the same as the first cross-sectional area and / or size d1. In yet another embodiment, the second cross-sectional area and / or size d2 is greater than the first cross-sectional area and / or size d1.

[0081] In one embodiment, the housing portion 64 includes a first length L1 along a second longitudinal axis A2 from the sidewall 50 to the first channel portion 68. The first length L1 may vary depending on the configuration or length of the in-cylinder pressure sensor 62 mounted in the housing portion 64. Additionally, the housing portion 64 may be formed with multiple segments or regions of different sizes and / or configurations to accommodate the size and shape of the in-cylinder pressure sensor 62 to be mounted. Therefore, the channel portion 66 disclosed herein can be used for any configuration of the in-cylinder pressure sensor 62 by shortening or lengthening the channel portion 66 based on the shape factor of the in-cylinder pressure sensor to be mounted.

[0082] The first channel portion 68 includes a second length L2 extending along a second longitudinal axis A2 from the housing portion 64 into the cylinder head body 31. The second channel portion 70 includes a third length L3 extending along a third longitudinal axis A3 from the first channel portion 68 into an opening at the combustion side 44 of the cylinder head body 31. In one embodiment, the first channel portion 68 extends to a spherical end wall 72, and the second channel portion 70 intersects with the spherical end wall 72. In another embodiment, the spherical end wall 72 is recessed and curved into the cylinder head body and is shaped to define part of a sphere.

[0083] The spherical end wall 72 prevents additional stress concentration in the cylinder head body 31, which could be created by forming the phase passage portions 68, 70 through a compound angle machining process. In an embodiment, the length L2 of the first passage portion 68 is greater than the length L3 of the second passage portion 70 to facilitate manufacturing and allow the use of a wider drill bit that is less prone to deviating during drilling over longer distances.

[0084] Other embodiments may envision employing configurations other than a spherical shape at the end wall 72 to reduce stress concentration. For example, a standard drill tip with a large radius between the tapered end and the cylindrical surface may be used to form the end wall 72. In another embodiment, a flat-bottomed drill bit with a large radius between its bottom and the cylindrical surface may be used to form the end wall 72. Other stress-reducing configurations are also envisioned and not excluded.

[0085] In one embodiment, the second passage portion 70 opens at the valve relief cutout 54. In a particular embodiment, the second passage portion 70 opens on the valve relief cutout 54, which is located downstream of the valve seat insert 56 and provides a lead-in for the placement of the valve seat insert 56 of the valve seat 40. In the closed position, the intake valve 38 (or exhaust valve) contacts the valve seat insert 56 but does not obstruct the opening of the second passage portion 70 on the valve relief cutout 54. The smaller cross-sectional area and / or dimension d2 of the second passage portion 70 allows the borehole of the second passage portion 70 to pass through the valve relief cutout 54 and be positioned on the combustion side 44 of the cylinder head body 31.

[0086] Opening the second channel portion 70 at the valve relief cutout 54 allows the opening for in-cylinder pressure sensing to be placed at the nearest "headroom" within the cylinder 12, thereby minimizing the overall length of the channel portion 66 and maximizing its acoustic resonant frequency. Conversely, other potential sensing locations within the cylinder 12 may exhibit lower acoustic resonant frequencies due to their greater distance from the sensor housing, which could interfere with and mask the pressure signal that the in-cylinder pressure sensor 62 should measure. Additionally, the opening at the valve relief cutout 54 positions the sensing channel portion 66 of the in-cylinder pressure sensor 62 as close as possible to the optimal pressure sensing location, which is closer to the centerline of the intake valve 38 (or exhaust valve) and further away from the bushing or edge of the cylinder 12.

[0087] refer to Figure 4 The diagram illustrates an embodiment of a portion of a manifold, such as an intake manifold 16 or an exhaust manifold 18. Manifolds 16 and 18 engage with a sidewall 50 of a cylinder head 30. Manifolds 16 and 18 include end walls 80 extending along the cylinder head 30. End walls 80 include a plurality of slots 82. Each slot 82 extends into the end wall 80 around an aligned sensor port in a sensor port 60. The slot 82 provides access to an in-cylinder pressure sensor 62 in that corresponding sensor port 60 and provides a path for a sensor cable 63.

[0088] In this implementation, each slot 82 is U-shaped and opens along one side. Slots 82 allow direct access to the corresponding cylinder pressure sensor 62 during servicing, and access to the cylinder pressure sensor 62 requires minimal removal of external engine components. Additionally, manifolds 16, 18 can be removed without interfering with or removing the cylinder pressure sensor 62 or its sensor cable 63, thus providing advantageous capabilities during cleaning, servicing, and diagnostics.

[0089] refer to Figure 5 An embodiment of a portion of a manifold gasket 90 is shown, which can be engaged between an intake manifold 16 or an exhaust manifold 18 and a sidewall 50 of the cylinder head body 31. The manifold gasket 90 includes a lower side 94 having a plurality of second slots 92 aligned with slots 82 of the manifolds 16, 18 and with a sensor port 60. Therefore, the manifold gasket 90 is also configured to receive the sensor port 60 of the cylinder head 30.

[0090] In this implementation, each slot 92 is U-shaped and opens along one side. The slot 92 allows direct access to the corresponding cylinder pressure sensor 62 during servicing, and access to the cylinder pressure sensor 62 requires minimal removal of external engine components. Additionally, the manifold gasket 90 can be removed without interfering with or removing the cylinder pressure sensor 62 or its sensor cable 63, thus providing advantageous capabilities during cleaning, servicing, and diagnostics.

[0091] Since the previous manifold did not include slot 82, and because this area was occupied by manifold material, the manifold gasket 90 is backward compatible with cylinder heads and manifolds that are not configured with sensor ports 60 and slot 82. Therefore, the same gasket 90 can be used regardless of whether the cylinder head is equipped with sensor ports 60. This reduces the number of parts and also lowers the likelihood of incorrectly fitting the manifold gasket to the cylinder head during assembly and / or repair.

[0092] refer to Figure 6 Another embodiment of the manifold gasket 90' similar to the manifold gasket 90 is shown. However, the manifold gasket 90' includes a transverse member 96' aligned with the end wall 94' of the manifold gasket 90'. The transverse member 96' extends through each of the slots 92' to provide increased stiffness to the manifold gasket 90' compared to the manifold gasket 90 having open-edge slots 92.

[0093] refer to Figures 8 to 10 A further embodiment of the sensor port 60 for accommodating the in-cylinder pressure sensor 62 is shown. Figures 8 to 10 The sensor ports 160, 160' of the embodiment include one or more configurations that attenuate the ringing sound detected by the in-cylinder pressure sensor 62 due to resonance in the channel portion and / or increase the resonant frequency. This distinguishes the acoustic frequencies of the sensor ports 160, 160' from the signal measured by the in-cylinder pressure sensor 62, thereby enhancing the ability of the in-cylinder pressure sensor 62 to measure in-cylinder pressure. For example, increasing the acoustic frequencies of the sensor ports 160, 160' better distinguishes the sensor port acoustic frequencies from the signal measured by the in-cylinder pressure sensor 62, thereby mitigating or reducing interference to the frequency range of the in-cylinder pressure signal that the in-cylinder pressure sensor 62 attempts to measure. It should be understood that, although Figures 8 to 10 Different configurations of the audio frequency enhancement geometry are shown, but two or more of these geometries can be combined in sensor ports 160, 160' configured according to this disclosure.

[0094] refer to Figure 8An embodiment of the audio enhancement sensor port is shown and designated as sensor port 160. Sensor port 160 includes a housing portion 164 and a channel portion 166, which provides fluid connection between the combustion chamber 14 and the in-cylinder pressure sensor 62 housed in the housing portion 164 of sensor port 160. The channel portion 166 opens at the combustion side 44 of the cylinder head body 31 in any manner and / or location similar to those discussed above with respect to sensor port 60.

[0095] The channel portion 166 may include multiple channel portions, such as a first channel portion 168 and at least one second channel portion 170. In one embodiment, the first channel portion 168 includes at least one transition channel portion 174 extending into the second channel portion 170. In the illustrated embodiment, at least one transition channel portion 174 includes a first transition channel portion 176 and a second transition channel portion 178. The housing portion 164, the first channel portion 168, and the first and second transition channel portions 176 and 178 extend along a second longitudinal axis A2 from the sidewall 50 of the cylinder head body 31 into the cylinder head body 31.

[0096] In one embodiment, housing portion 164 extends collinearly with the first channel portion 168, the first transition channel portion 176, and the second transition channel portion 178 of sensor port 160. At least one second channel portion 170 extends non-collinearly from at least one transition channel portion 174 along a third longitudinal axis A3 forming an angle B with the second longitudinal axis A2. In another embodiment, the second channel portion 170 is collinear with the transition channel portion 174.

[0097] In one embodiment, each of the first transition channel portion 176 and the second transition channel portion 178 is oriented obliquely relative to at least one second channel portion 170. In other embodiments, the second channel portion 170 is orthogonal to the first channel portion 168 and / or at least one transition channel portion 174. Other embodiments are contemplated to provide two or more non-collinear second channel portions 170, such as offset channel portions, wherein the centerlines of the channels do not intersect each other and / or are parallel to each other. In one embodiment, each channel portion 168, 170, 176, 178 is straight. However, non-straight configurations of one or more of the channel portions 168, 170, 176, 178 are not excluded, such as one or more of the channel portions 168, 170, 176, 178 including a curved configuration along all or part of its length.

[0098] In one embodiment, at least one transition channel portion 174 of the first channel portion 168 includes a first cross-sectional area and / or dimension d1 orthogonal to the second longitudinal axis A2. In another embodiment, the second transition channel portion 178 includes a cross-sectional area and / or dimension d1, and the first transition channel portion 176 includes a larger cross-sectional area and / or dimension than the second transition channel portion 178. In yet another embodiment, the first channel portion 168 includes a cross-sectional area and / or dimension adjacent to and extending from the housing portion 164, which is larger than the first transition channel portion 176. The second channel portion 170 includes a second cross-sectional area and / or dimension d2 orthogonal to the third longitudinal axis A3.

[0099] In one embodiment, the first channel portion 168 includes a cross-sectional dimension greater than or equal to the cross-sectional dimension of the first transition portion 176 and / or the second transition portion 178. In another embodiment, the first channel portion 168 includes a cross-sectional dimension less than or equal to the cross-sectional dimension of the first transition portion 176 and / or the second transition portion 178.

[0100] In one embodiment, the first cross-sectional area and / or dimension d1 is smaller than the second cross-sectional area and / or dimension d2 to distinguish the acoustic frequency of the channel portion 166 from the signal range to be detected by the in-cylinder pressure sensor 62. In another embodiment, the ratio of d2 to d1 is greater than 1. In yet another embodiment, the ratio of d2 to d1 is maximized to increase the acoustic resonant frequency of the channel portion 166 beyond the signal range to be detected by the in-cylinder pressure sensor 62. Other embodiments may envision a ratio of d2 to d1 equal to or less than 1.

[0101] In embodiments where the cross-sections of channel portions 168, 170, 176, and 178 are circular, dimensions d1 and d2 are the diameters of the corresponding channel portions in the second transition channel portion 178 and the second channel portion 170. Other embodiments may envision one or more of the channel portions 168, 170, 176, and 178 having non-circular cross-sections.

[0102] refer to Figure 9A further embodiment of the sensor port 160 is shown. In this embodiment, the housing portion 164 includes a first length L1 along a second longitudinal axis A2 from the sidewall 50 to the first channel portion 168. The housing portion 164 may be formed along the first length L1 with multiple segments or regions of different sizes and / or configurations to accommodate the size and shape of the in-cylinder pressure sensor 62 to be mounted. The first length L1 may vary depending on the configuration or length of the in-cylinder pressure sensor 62 mounted in the housing portion 164. In this embodiment, the tilt angle TA between the second longitudinal axis A2 and the combustion side (fire plate) 44 of the cylinder head body 31 is selected such that the in-cylinder pressure sensor 62 can be inserted into the cylinder head body 31 to a certain depth, thereby allowing the second length L2 of the second transition channel portion 178 to be minimized.

[0103] The second length L2 of the second transition passage portion 178 of the passage portion 166 extends along the second longitudinal axis A2 from the second passage portion 170 toward the housing portion 164. The second passage portion 170 includes a third length L3 that extends along the third longitudinal axis A3 from the second transition passage portion 178 to an opening at the combustion side 44 of the cylinder head body 31.

[0104] In one embodiment, the second channel portion 170 extends to the spherical end wall 172, while the second transition channel portion 178 intersects the spherical end wall 172. In another embodiment, the spherical end wall 172 is recessed and curved into the cylinder head body and shaped as part of a defining sphere. Other configurations of the end wall 172 are also conceivable, as discussed above with respect to end wall 72. The spherical end wall 172 allows the second transition channel portion 178 to intersect with the second channel portion 170 without creating a sharp-edged break, thereby reducing stress concentration. The spherical end wall 172 provides stress relief, ease of machining, and improved acoustic performance of the channel portion 166.

[0105] In one embodiment, the length L2 of the channel portion 166, such as along the second transition channel portion 178, is less than the length L3 of the second channel portion 170, to distinguish the acoustic frequency of the channel portion 166 from the signal range measured by the in-cylinder pressure sensor 62. In another embodiment, the ratio of L2 to L3 is less than 1. In yet another embodiment, the ratio of L2 to L3 is minimized to increase the acoustic frequency of the channel portion 166 beyond the signal range to be detected by the in-cylinder pressure sensor 62. Other embodiments may envision a ratio of L2 to L3 equal to or greater than 1.

[0106] refer to Figure 10Another embodiment of sensor port 160' similar to sensor port 160 is shown. However, sensor port 160' includes a tapered cross-section along at least one transition channel portion 174' and / or along a second channel portion 170'. The tapered channel portion increases the acoustic frequency of channel portion 166 to better distinguish the signal to be measured by in-cylinder pressure sensor 62. The tapered channel portion also suppresses the amplitude of pressure oscillations while the inherent frequency of the pressure oscillations is high enough not to interfere with the ability to measure frequencies indicative of combustion performance. For example, there is a gain as a function of frequency, and this gain is greater than 1 near resonance. The tapered channel portion is configured to reduce the gain and make the gain as small as possible.

[0107] In the illustrated embodiment, a single transition channel portion 176' is disposed between the first channel portion 168 and the second channel portion 170'. The transition channel portion 176' includes a cross-sectional area or dimension d1 that tapers gradually from the first channel portion 168 to the second channel portion 170' at a cone angle C1. The second channel portion 170' includes a second cross-sectional area or dimension d2 that tapers gradually from its opening at the combustion side 44 to the transition channel portion 176' at a cone angle C2. Other embodiments are contemplated where the transition channel portion 176' tapers away from the second channel portion 170' and / or the second channel portion 170' tapers away from the transition channel portion 176'.

[0108] In the illustrated embodiment, the cross-sectional area and / or dimensions d1 and d2 gradually taper along the entire length of the respective channel portion. Other embodiments may envision tapered dimensions extending along a length smaller than the corresponding channel portion. Still other embodiments may envision multiple channel portions extending from a single housing portion to fluidly connect the combustion chamber 14 to the in-cylinder pressure sensor 62.

[0109] The sensor ports 60, 160, and 160' disclosed herein can be manufactured using any suitable technique. For example, the cylinder head 30 can be manufactured by 3D printing to include the sensor ports 60, 160, and 160'. Other embodiments are envisioned whereby the sensor ports 60, 160, and 160' are cast into place together with the cylinder head 30 and / or configured within the cylinder head 30 so that they can be formed using appropriate tools.

[0110] Many aspects of this disclosure are conceivable. For example, one aspect relates to an internal combustion engine configured for in-cylinder pressure sensing. The internal combustion engine includes at least one cylinder, which includes a combustion chamber for receiving charge flow and fuel for combustion within the combustion chamber. The internal combustion engine also includes a cylinder head mounted to the at least one cylinder. The cylinder head includes an opening for providing charge flow to or receiving exhaust flow from the combustion chamber through the opening. The cylinder head also includes: a valve relief cutout extending around the opening; and a sensor port for receiving an in-cylinder pressure sensor in fluid communication with the combustion chamber. The sensor port includes: a housing portion for receiving the in-cylinder pressure sensor; and a channel portion extending from the valve relief cutout to the housing portion to fluidly connect the in-cylinder pressure sensor received in the housing portion to the combustion chamber.

[0111] In one embodiment, the valve seat includes a valve seat insert mounted in the cylinder head, and the valve relief cutout extends from the valve seat insert toward the combustion chamber. A passage portion opens at the valve relief cutout to the combustion chamber.

[0112] In a further embodiment, the valve relief cutout extends outward toward the combustion chamber.

[0113] In one implementation, a manifold is mounted to the cylinder head. The manifold is configured to provide the charging flow to the cylinder head or receive the exhaust flow from the cylinder.

[0114] In a further embodiment, the manifold includes an end wall extending along the cylinder head and a slot extending into the end wall around the sensor port. The slot provides access to the in-cylinder pressure sensor in the sensor port.

[0115] In a further embodiment, a manifold gasket is disposed between the cylinder head and the manifold. The manifold gasket includes a second slot that aligns with a slot in the manifold.

[0116] In a further embodiment, the manifold gasket includes a transverse member aligned with the end wall of the manifold, the transverse member extending through the second slot.

[0117] In one embodiment, the sensor port includes a first channel portion extending from the housing portion toward the combustion chamber. The channel portion also includes a second channel portion oriented at an angle relative to the first channel portion. The second channel portion extends from the first channel portion to the valve relief cutout.

[0118] In a further embodiment, the first channel portion includes a first cross-sectional area. The second channel portion includes a second cross-sectional area smaller than the first cross-sectional area.

[0119] In the implementation, the housing portion is axially aligned with the first channel portion.

[0120] According to another aspect of this disclosure, a cylinder head for an internal combustion engine is provided. The cylinder head includes a cylinder head body having a combustion side facing the cylinder. The cylinder head body also includes a sensor port. The sensor port includes: a housing portion configured to receive an in-cylinder pressure sensor; a first channel portion extending from the housing portion into the cylinder head body; and at least one second channel portion extending non-collinearly to the combustion side of the cylinder head.

[0121] In the implementation scheme, the first channel portion is collinear with the housing portion.

[0122] In the implementation, the first channel portion is straight, and the at least one second channel portion is straight.

[0123] In the implementation scheme, the first channel portion is longer than the at least one second channel portion.

[0124] In one embodiment, the first channel portion includes a first cross-sectional dimension. The at least one second channel portion includes a second cross-sectional dimension smaller than the first cross-sectional dimension.

[0125] In one embodiment, the first channel portion extends from the housing portion to the spherical end wall. The at least one second channel portion intersects the spherical end wall.

[0126] In one embodiment, at least one opening on the combustion side of the cylinder head includes a valve relief cutout. The at least one second passage portion opens on the valve relief cutout.

[0127] In one embodiment, the cylinder head body includes sidewalls to which a manifold is mounted. The housing portion of the sensor port opens at the sidewall of the cylinder head body.

[0128] In one embodiment, the first channel portion and the at least one second channel portion each include a circular cross-section. The diameter of the first channel portion is larger than the diameter of the at least one second channel portion.

[0129] In the implementation, the at least one opening is part of the air intake formed by the cylinder head.

[0130] According to another aspect of this disclosure, a cylinder head for an internal combustion engine is disclosed. The cylinder head includes a cylinder head body comprising a combustion side facing the cylinder and a sensor port for an in-cylinder pressure sensor. The sensor port includes: a housing portion configured to receive the in-cylinder pressure sensor; and a channel portion extending from the housing portion to the combustion side of the cylinder head. The channel portion is configured to attenuate ringing sounds generated by resonance within the channel portion.

[0131] According to another aspect of this disclosure, a cylinder head for an internal combustion engine is provided. The cylinder head includes a cylinder head body having a combustion side facing the cylinder. The cylinder head body also includes a sensor port for an in-cylinder pressure sensor. The sensor port includes: a housing portion configured to receive the in-cylinder pressure sensor; and a channel portion extending from the housing portion to the combustion side of the cylinder head. The channel portion is configured to increase the resonant frequency.

[0132] In the implementation, the channel portion is a single channel extending from the housing portion to the combustion chamber.

[0133] In one embodiment, the channel portion includes a first channel portion extending from the housing portion into the cylinder head and a second channel portion extending from the combustion side of the cylinder head into the cylinder head. The first channel portion includes at least one transition channel portion connecting the first channel portion to the second channel portion. The first channel portion, the second channel portion, and the at least one transition channel portion are configured to distinguish the acoustic frequency of the channel portion from the signal detected by the in-cylinder pressure sensor.

[0134] In one embodiment, the first channel portion includes a first cross-sectional dimension, the second channel portion includes a second cross-sectional dimension, and the ratio of the second cross-sectional dimension to the first cross-sectional dimension is not equal to 1.

[0135] Further implementations may envision the ratio of the second cross-sectional dimension to the first cross-sectional dimension being equal to 1, greater than 1, or less than 1.

[0136] In one embodiment, the first channel portion extends along a first axis and includes a first length along the first axis, the second channel portion extends along a second axis and includes a second length along the second axis, and the ratio of the first length to the second length is not equal to 1.

[0137] Further embodiments may be provided in which the ratio of the first length to the second length is equal to 1, greater than 1, or less than 1.

[0138] In one embodiment, the at least one transition channel portion extends along a first axis and includes a first cross-sectional dimension that tapers gradually along the first axis. The second channel portion extends along a second axis and includes a second cross-sectional dimension that tapers gradually along the second axis.

[0139] In one embodiment, the at least one transition channel portion includes a first transition channel portion extending from the first channel portion toward the second channel portion. The at least one transition channel portion also includes a second transition channel portion extending from the first transition channel portion to the second channel portion.

[0140] In one embodiment, the second transition channel portion includes a first cross-sectional dimension, the second channel portion includes a second cross-sectional dimension, and the ratio of the second cross-sectional dimension to the first cross-sectional dimension is not equal to 1.

[0141] In the implementation scheme, the first transition channel portion includes a third cross-sectional dimension that is larger than the first cross-sectional dimension.

[0142] In one implementation, the first transition channel portion includes a third cross-sectional dimension that is less than or equal to the first cross-sectional dimension.

[0143] In the implementation scheme, the first channel portion includes a fourth cross-sectional dimension that is larger than the third cross-sectional dimension.

[0144] In the implementation scheme, the first channel portion includes a fourth cross-sectional dimension that is less than or equal to the third cross-sectional dimension.

[0145] In the implementation, the housing portion, the first channel portion, and the at least one transition channel portion are collinear with each other.

[0146] In the implementation, the second channel portion is tilted relative to the at least one transition channel portion.

[0147] In the implementation scheme, the second channel portion is collinear with the at least one transition channel portion.

[0148] In the implementation scheme, the second channel portion is orthogonal to the at least one transition channel portion.

[0149] In the implementation scheme, the second channel portion is not collinear with the at least one transition channel portion.

[0150] In one embodiment, the second channel portion is offset from the at least one transition channel portion such that the second channel portion and the at least one transition channel portion include centerlines that do not intersect each other and / or are parallel to each other.

[0151] In the implementation, the second channel portion and / or the at least one transition channel portion is not straight, but includes a curved configuration along at least a portion of its length.

[0152] In one embodiment, the channel portion includes at least one transition channel portion located between the housing portion and the second channel portion, the second channel portion extending from the combustion side of the cylinder head. The at least one transition channel portion includes a first cross-sectional dimension smaller than the second cross-sectional dimension of the second channel portion, or the at least one transition channel portion includes a first length smaller than the second length of the second channel portion.

[0153] In one embodiment, the first cross-sectional dimension is smaller than the second cross-sectional dimension, and the first length is smaller than the second length.

[0154] In one embodiment, the channel portion includes at least one transition channel portion located between the housing portion and the second channel portion, the second channel portion extending from the combustion side of the cylinder head. The at least one transition channel portion includes a first tapered cross-sectional dimension, or the second channel portion includes a second tapered cross-sectional dimension.

[0155] In the implementation scheme, at least one of the at least one transition channel portion and the second channel portion is tapered.

[0156] While the invention has been shown and described in detail in the accompanying drawings and the foregoing description, these should be considered illustrative rather than restrictive in nature, and it should be understood that only certain exemplary embodiments have been shown and described. Those skilled in the art will understand that many modifications may be made to the exemplary embodiments without departing substantially from the invention. Therefore, all such modifications are intended to be included within the scope of this disclosure as defined by the appended claims. Reading the claims, it is not intended that the claims be limited to only one item when words such as “a,” “one,” “at least one,” or “at least a portion” are used, unless expressly stated otherwise in the claims. When the language “at least a portion” and / or “a portion” is used, the item may include a portion and / or the entire item unless expressly stated otherwise.

Claims

1. An internal combustion engine configured for in-cylinder pressure sensing, the internal combustion engine comprising: at least one cylinder including a combustion chamber to receive a charge flow and a fuel for combustion; and a cylinder head mounted to the at least one cylinder, the cylinder head including an opening to provide the charge flow to or receive an exhaust flow from the combustion chamber, the cylinder head including: a valve relief cut extending around the opening; and a sensor port to house an in-cylinder pressure sensor in fluid communication with the combustion chamber, the sensor port including: a housing portion to house the in-cylinder pressure sensor; and a channel portion extending from the valve relief cut to the housing portion to fluidly connect the in-cylinder pressure sensor housed in the housing portion with the combustion chamber.

2. The internal combustion engine of claim 1, wherein the opening includes: a valve seat insert mounted in the cylinder head; and the valve relief cut extends from the valve seat insert toward the combustion chamber, the channel portion opens to the combustion chamber at the valve relief cut.

3. The internal combustion engine of claim 2, wherein the valve relief cut flares outwardly from the valve seat insert toward the combustion chamber.

4. The internal combustion engine of claim 1, further comprising a manifold mounted to the cylinder head, the manifold configured to provide the charge flow to or receive an exhaust flow from the cylinder head.

5. The internal combustion engine of claim 4, wherein the manifold includes: an end wall extending along the cylinder head; and a slot extending into the end wall around the sensor port, the slot providing access to the in-cylinder pressure sensor in the sensor port.

6. The internal combustion engine of claim 5, further comprising a manifold gasket between the cylinder head and the manifold, wherein the manifold gasket includes a second slot aligned with the slot of the manifold.

7. The internal combustion engine of claim 6, wherein the manifold gasket includes a cross member aligned with the end wall of the manifold, the cross member extending through the second slot.

8. The internal combustion engine of claim 1, wherein the channel portion of the sensor port includes: a first channel portion extending from the housing portion toward the combustion chamber; and a second channel portion oriented obliquely relative to the first channel portion, the second channel portion extending from the first channel portion to the valve relief cut.

9. The internal combustion engine of claim 8, wherein: the first channel portion includes a first cross-sectional area; and the second channel portion includes a second cross-sectional area less than the first cross-sectional area.

10. The internal combustion engine of claim 8, wherein the housing portion is axially aligned with the first channel portion. ​ ​

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