Description:A PISTON CROWN WITH VANES

TECHNICAL FIELD
[0001] The present subject matter described herein relates to a piston in an internal combustion engine in a vehicle. The present invention is particularly related to an improved piston design that improves air-fuel mixing by using the swirl flow near spark ignition timing.

BACKGROUND
[0002] Background description includes information that may be useful in understanding the present subject matter.
[0003] An internal combustion engine of a vehicle has an engine block that has a cylinder bore and a cylinder head, wherein the cylinder head has a flame deck surface having a spark plug provided at one end of the cylinder bore. A piston is positioned inside the cylinder bore, wherein the piston is connected to a rotatable crankshaft and configured to reciprocate within the cylinder bore along a longitudinal direction.
[0004] Further, an intake port of the internal combustion engine has numerous components that interact with one or more fuel jets that are injected into it in a standard port fuel injection engine.
[0005] Further, in the existing designs, the fuel is sprayed through the fuel jet in the intake port, which then atomizes and it enters into the cylinder. Because of only the tumble motion, the fuel and air may not mix properly which might lead to improper flame propagation and poor combustion stability. It is therefore desirable to guide the air fuel mixture such that it forms an improved swirl in addition to tumble motion which increases turbulence and flame speed. Also, to improve mixing of air with incoming fuel in the combustion chamber which improves fuel burning and engine efficiency.
OBJECTS OF THE DISCLOSURE
[0006] It forms an object of the present disclosure to overcome the aforementioned and other drawbacks/limitations in the existing solutions available in the form of related prior arts.
[0007] It is a primary object of the present disclosure is to improve the air-fuel mixing in a combustion chamber.
[0008] It is another object of the present disclosure to guide the air-fuel mixture towards the spark plug in a swirl motion.
[0009] It is another object of the present disclosure to increase turbulence and flame speed inside the combustion chamber .
[0010] It is another object of the present disclosure to improve fuel burning and engine efficiency.
[0011] These and other objects and advantages of the present subject matter will be apparent to a person skilled in the art after consideration of the following detailed description taken into consideration with accompanying drawings in which preferred embodiments of the present subject matter are illustrated.

SUMMARY
[0012] A solution to one or more drawbacks of existing technology and additional advantages are provided through the present disclosure. Additional features and advantages are realized through the technicalities of the present disclosure. Other embodiments and aspects of the disclosure are described in detail herein and are considered to be a part of the claimed disclosure.
[0013] The present disclosure provides a solution in the form of a piston for use in an internal combustion engine, the piston includes a body portion having a cylindrical shape and configured to reciprocate within a cylinder bore of the internal combustion engine and a crown portion formed at a top portion of the piston, the crown portion comprises a piston bowl having a concave shape that is defined within a circular wall of the crown portion, the circular wall extends peripherally around the piston body along a circumferential direction. A plurality of protrusions extend from the circular wall toward the piston bowl and disposed along the periphery of the piston bowl adjacent the circular wall, each of the protrusion is positioned at an equal angular distance in radial direction. A pocket structure is defined in between the two consecutive protrusions within the piston bowl. A continuous connecting portion is provided in between the piston bowl and the circular wall including each of the protrusion along the periphery of the piston bowl defining a concave shape and a vane assembly having of a plurality of vanes. The plurality of vanes are provided in a radial direction, where centre of the vane assembly is in-line with the centre of the crown portion and the plurality of vanes are in convex shape and extending in upward from plane of the piston bowl.
[0014] In an aspect, a centre end of the each of the vane from the plurality of vanes is connected with the centre of the crown portion and a tip end of the vane is facing peak of the protrusion and connected with the continuous connecting portion defined between the peak of the protrusion and the piston bowl.
[0015] In an aspect, wherein the plurality of vanes defines twist angle, the twist angle increases from the centre end to the tip end to direct the air-fuel mixture in the swirl direction.
[0016] In an aspect, the plurality of vanes are curved to match with swirl direction to direct the air-fuel mixture.
[0017] In an aspect, the vane assembly is integrated with the crown portion of the piston.
[0018] In an aspect, width of the plurality of vanes increases from the center end till middle of radius of the vane and decreases from the middle of the radius of the vane till the tip end.
[0019] In an aspect, the continuous connecting portion directs an air-fuel mixture towards curved profile of the corresponding vane.
[0020] In an aspect, the pocket structure is offset position with respect to the plurality of vanes.
[0021] The foregoing summary is illustrative only and is not intended to be in any way limiting. In addition to the illustrative aspects, embodiments, and features described above, further aspects, embodiments, and features will become apparent by reference to the drawings and the following detailed description.

BRIEF DESCRIPTION OF ACCOMPANYING DRAWINGS
[0022] It is to be noted, however, that the appended drawings illustrate only typical embodiments of the present subject matter and are therefore not to be considered for limiting of its scope, for the present disclosure may admit to other equally effective embodiments. The detailed description is described with reference to the accompanying figures. In the figures, a reference number identifies the figure in which the reference number first appears. The same numbers are used throughout the figures to reference like features and components. Some embodiments of system or methods or structure in accordance with embodiments of the present subject matter are now described, by way of example, and with reference to the accompanying figures, in which:
[0023] Fig. 1a illustrates a crown portion of a piston according to the present disclosure;
[0024] Fig. 1b illustrates a peak-like shape of a protrusion according to the present disclosure;
[0025] Fig. 1c illustrates center axis of the vane assembly, a crown portion and a pocket structure according to the present disclosure;
[0026] Fig. 2 is sectional view illustrating a vane of a vane assembly on the crown portion of the piston according to the present disclosure;
[0027] Fig. 3 illustrates a pathway of air-fuel mixture from intake port and forming swirl and tumble according to the present disclosure.
[0028] The figures depict embodiments of the present subject matter for illustration only. A person skilled in the art will easily recognize from the following description that alternative embodiments of the structures and methods illustrated herein may be employed without departing from the principles of the disclosure described herein.

DETAILED DESCRIPTION OF INVENTION
[0029] The detailed description of various exemplary embodiments of the disclosure is described herein with reference to the accompanying drawings. It should be noted that the embodiments are described herein in such details as to communicate the disclosure. However, the amount of details provided herein is not intended to limit the anticipated variations of embodiments; on the contrary, the intention is to cover all modifications, equivalents, and alternatives falling within the scope of the present disclosure as defined by the appended claims.
[0030] It is also to be understood that various arrangements may be devised that, although not explicitly described or shown herein, embody the principles of the present disclosure. Moreover, all statements herein reciting principles, aspects, and embodiments of the present disclosure, as well as specific examples, are intended to encompass equivalents thereof.
[0031] It should also be noted that in some alternative implementations, the functions/acts noted may occur out of the order noted in the figures. For example, two figures shown in succession may be executed concurrently or may sometimes be executed in the reverse order, depending upon the functionality/acts involved.
[0032] Unless otherwise defined, all terms (including technical and scientific terms) used herein have the same meaning as commonly understood by one of ordinary skill in the art to which example embodiments belong. It will be further understood that terms, e.g., those defined in commonly used dictionaries, should be interpreted as having a meaning that is consistent with their meaning in the context of the relevant art and will not be interpreted in an idealized or overly formal sense unless expressly so defined herein.
[0033] In the following detailed description of the embodiments of the disclosure, reference is made to the accompanying drawings that form a part hereof, and in which are shown by way of illustration of specific embodiments in which the disclosure may be practiced. These embodiments are described in sufficient detail to enable those skilled in the art to practice the disclosure, and it is to be understood that other embodiments may be utilized and that changes may be made without departing from the scope of the present disclosure. The following description is, therefore, not to be taken in a limiting sense.
[0034] Hereinafter, a description of an embodiment with several components in communication with each other does not imply that all such components are required. On the contrary, a variety of optional components are described to illustrate the wide variety of possible embodiments of the present disclosure.
[0035] The present invention discloses a piston that is used in an internal combustion engine. The present invention further discloses of improving the design of the piston crown such that a swirl-type flow is induced near spark ignition timing [690° to 750° crank angle].
[0036] Referring to FIG. 1a and FIG. 1b, the body portion of the piston (100) has a cylindrical shape and the piston (100) is configured to reciprocate within a cylinder bore of the internal combustion engine.
[0037] Further, the piston (100) has a crown portion (101) that forms a top portion of the piston (100). The crown portion (101) is comprised of a piston bowl (102) and a circular wall (103). The piston bowl (102) has a concave shape that is defined within the circular wall (103) of the crown portion (101). The concave shape defines a volume configured to receive a fuel-air mixture.
[0038] The circular wall (103) extends peripherally around the piston body along the circumferential direction. Further, the circular wall (103) has a plurality of protrusions (104) that are extended from the circular wall (103) towards the piston bowl (102) and disposed along periphery of the piston bowl (102) that is located adjacent the circular wall (103).
[0039] The protrusions (104) form a peak-like shape (110) (refer to Fig. 1b) with respect to the piston bowl (102). The peak-like shape extend in upward direction from the circular wall (103) as indicated by the lines forming an inclined shape. The protrusions (104) are provided such that the air-fuel mixture enters from an intake port, is easily guided and transferred to the piston bowl (102).
[0040] Each of the protrusions (104) is positioned at an equal angular distance in a radial direction forming the peak like shape (110) and thereby leading the air-fuel mixture from all the circumferential directions towards the piston bowl (102).
[0041] Further, a pocket structure (106) is defined in between the two consecutive protrusions (104) within the piston bowl (102). The pocket structure (106) is an empty space that is slanted and is configured to divert the flow of the air-fuel mixture towards the center of the piston crown (101) where the vane assembly is also centrally located.
[0042] Furthermore, a continuous connecting portion (107) is provided in between the piston bowl (102) and the circular wall (103) that includes each of the protrusions (104). The continuous connecting portion (107) is provided along the periphery of the piston bowl (102) and the continuous connecting portion (107) defines a concave shape.
[0043] The concave shape of the continuous connecting portion (107) is such that it guides the air-fuel mixture towards the center of the piston bowl (102) and achieves the common objective, i.e., to direct the air-fuel mixture towards curved profile of the corresponding vane of a plurality of vanes (108) that forms a vane assembly.
[0044] The vane assembly has a plurality of vanes (108). Each vane (108) from the plurality of vanes (108) in the vane assembly is provided in the radial direction at equal radial distance from each other. The vane assembly is integrated with the crown portion (101) of the piston bowl (102).
[0045] The pocket structure (106) is offset with respect to the plurality of vanes (108). The offset helps in increasing the pocket structure (106) area which provides increased flow of air-fuel mixture towards the plurality of vanes (108). This arrangement improves the swirling action.
[0046] Referring to FIG. 1c, the centre of the vane assembly (109) is in-line with the centre of the crown portion (105) of the piston (100). Further, the center of the pocket structure (111) is offset from the center of the vane assembly (109) and the centre of the crown portion (105). Furthermore, the plurality of vanes (108) are in a convex shape and extend in upward direction from plane of the piston bowl (102).
[0047] Referring to FIG. 2, it shows a single vane (108) derived from a plurality of vanes (108). Each vane (108) from the plurality of the vanes (108) have a similar structure as illustrated in the figure 2.
[0048] The vane (108) has two ends, i.e., a centre end (201) and a tip end (202), where the centre end (201) of the vane (108) is connected with the centre of the crown portion (105) of the piston (100) and the tip end (202) of the vane (108) faces the peak of the protrusion (104). The tip end (202) is connected with the continuous connecting portion (107) that is defined between the peak of the protrusion (104) and the piston bowl (102).
[0049] Further, the width of the vane (108) increases from the center end (201) till a middle portion (203) of radius of the vane (108) and decreases from the middle portion (203) of the radius of the vane (108) till the tip end (202) of the vane (108).
[0050] The vane (108) is curved to generate swirl flow to maximize air-fuel mixing.
[0051] The vane (108) define a twist angle. The twist angle increases from the centre end (201) to the tip end (202) to direct the air-fuel mixture in the swirl direction. In exemplary explanation, the twist angle at R1 of the vane that is connected with the centre of the crown portion (105) is approx. 9 degrees. The twist angle at R2 of the vane that is connected with the centre of the crown portion (105) is approx. 27 degrees. The twist angle at R3 of the vane that is connected with the centre of the crown portion (105) is approx. 83 degrees. The twist angle of the vane (108) can vary as per dimensions and structure of the piston crown.
[0052] Referring to FIG. 3, the pathway of air-fuel mixture from intake port (301) is disclosed. The flow enters through the intake port (301) and hits the continuous connecting portion (107). Then the flow is guided by the pocket structure (106) towards the vane (108). Afterwards, the vane (108) then pushes the air-fuel mixture into the cylinder giving a swirling motion.

TECHNICAL ADVANTAGES
[0053] With the help of the solution as proposed herein in the context of the present disclosure, the air fuel mixing by using the swirl flow near spark ignition timing [690° to 750° crank angle] is acheived.
[0054] With the introduction of swirl flow, Peak Firing Pressure (PFP) [PCP], Mass Burn Fraction (MBF) 50, combustion duration [10-90] and Indicated Mean Effective Pressure (IMEP) is increased.
[0055] The pocket structure and the plurality of vanes are offset with respect to their centers so that more air-fuel mixture can be captured in the pocket structure and guided towards the vane.
[0056] Lastly with the increased swirl flow, the turbulence and combustion speed is increased.
[0057] It will be understood by those within the art that, in general, terms used herein, and especially in the appended claims (e.g., bodies of the appended claims) are generally intended as “open” terms (e.g., the term “including” should be interpreted as “including but not limited to,” the term “having” should be interpreted as “having at least,” the term “includes” should be interpreted as “includes but is not limited to,” etc.). It will be further understood by those within the art that if a specific number of an introduced claim recitation is intended, such an intent will be explicitly recited in the claim, and in the absence of such recitation, no such intent is present. For example, as an aid to understanding, the following appended claims may contain usage of the introductory phrases “at least one” and “one or more” to introduce claim recitations. However, the use of such phrases should not be construed to imply that the introduction of a claim recitation by the indefinite articles “a” or “an” limits any particular claim containing such introduced claim recitation to disclosures containing only one such recitation, even when the same claim includes the introductory phrases “one or more” or “at least one” and indefinite articles such as “a” or “an” (e.g., “a” and/or “an” should typically be interpreted to mean “at least one” or “one or more”); the same holds true for the use of definite articles used to introduce claim recitations. Also, even if a specific number of an introduced claim recitation is explicitly recited, those skilled in the art will recognize that such recitation should typically be interpreted to mean at least the recited number (e.g., the bare recitation of “two recitations,” without other modifiers, typically means at least two recitations or two or more recitations). Furthermore, in those instances where a convention analogous to “at least one of A, B, and C, etc.” is used, in general, such construction is intended in the sense one having skill in the art would understand the convention (e.g., “a system having at least one of A, B, and C” would include but not be limited to systems that have A alone, B alone, C alone, A and B together, A and C together, B and C together, and/or A, B, and C together, etc.). In those instances, where a convention analogous to “at least one of A, B, or C, etc.” is used, in general, such construction is intended in the sense one having skill in the art would understand the convention (e.g., “a system having at least one of A, B, or C” would include but not be limited to systems that have A alone, B alone, C alone, A and B together, A and C together, B and C together, and/or A, B, and C together, etc.). It will be further understood by those within the art that virtually any disjunctive word and/or phrase presenting two or more alternative terms, whether in the description, claims, or drawings, should be understood to contemplate the possibilities of including one of the terms, either of the terms or both terms. For example, the phrase “A or B” will be understood to include the possibilities of “A” or “B” or “A and B.”
[0058] It will be further appreciated that functions or structures of a plurality of components or steps may be combined into a single component or step, or the functions or structures of one-step or component may be split among plural steps or components. The present disclosure contemplates all of these combinations. Unless stated otherwise, dimensions and geometries of the various structures depicted herein are not intended to be restrictive of the disclosure, and other dimensions or geometries are possible. Also, while a feature of the present disclosure may have been described in the context of only one of the illustrated embodiments, such feature may be combined with one or more other features of other embodiments, for any given application. It will also be appreciated from the above that the fabrication of the unique structures herein and the operation thereof also constitute methods in accordance with the present disclosure. The present disclosure also encompasses intermediate and end products resulting from the practice of the methods herein. The use of “comprising” or “including” also contemplates embodiments that “consist essentially of” or “consist of” the recited feature. , Claims:We claim:
1. A piston (100) for use in an internal combustion engine, the piston (100) comprising:
a body portion having a cylindrical shape and configured to reciprocate within a cylinder bore of the internal combustion engine; and
a crown portion (101) formed at a top portion of the piston (100), the crown portion (101) comprises a piston bowl (102) having a concave shape that is defined within a circular wall (103) of the crown portion (101), the circular wall (103) extends peripherally around the piston body along a circumferential direction;
characterized in that
a plurality of protrusions (104) extend from the circular wall (103) toward the piston bowl (102) and disposed along the periphery of the piston bowl (102) adjacent to the circular wall (103), each of the protrusion (104) is positioned at an equal angular distance in a radial direction;
a pocket structure (106) defined in between the two consecutive protrusions (104) within the piston bowl (102);
a continuous connecting portion (107) provided in between the piston bowl (102) and the circular wall (103), wherein the continuous connecting portion (107) includes each of the protrusions (104) along the periphery of the piston bowl (102) and defines a concave shape; and
a vane assembly having a plurality of vanes (108) is provided in the radial direction, where a centre of the vane assembly (109) is in-line with the centre of the crown portion (105), each of the vane from the plurality of vanes (108) are in convex shape and extending in upward from plane of the piston bowl (102).
2. The piston (100) as claimed in claim 1, wherein a centre end (201) the plurality of vanes (108) is connected with the centre of the crown portion (105) and a tip end (202) of the plurality of vanes (108) is facing peak of the protrusion (104) and connected with the continuous connecting portion (107) defined between the peak of the protrusion (104) and the piston bowl (102).
3. The piston (100) as claimed in claim 1, wherein the plurality of vanes (108) defines twist angle, the twist angle increases from the centre end (201) to the tip end (202) to direct the air-fuel mixture in the swirl direction.
4. The piston (100) as claimed in claim 3, wherein the plurality of vanes (108) are curved to match with swirl direction to direct the air-fuel mixture.
5. The piston (100) as claimed in claim 3, wherein the vane assembly is integrated with the crown portion (101) of the piston (100).
6. The piston (100) as claimed in claim 1, wherein width of the plurality of vanes (108) increases from the center end (201) till a middle portion (203) of radius of the plurality of vanes (108) and decreases from the middle of the radius of the plurality of vanes (203) till the tip end (202).
7. The piston (100) as claimed in claim 1, wherein the continuous connecting portion (207) directs an air-fuel mixture towards curved profile of the corresponding vane.
8. The piston (100) as claimed in claim 1, wherein the pocket structure (106) is offset with respect to the plurality of vanes (108).