Description:TECHNICAL FIELD

[001] Present disclosure relates to internal combustion engines. Particularly, the present disclosure relates to a camshaft of an internal combustion engine that ensures high rigidity and aids in improving noise, vibration, and harshness of the internal combustion engine.

BACKGROUND OF THE DISCLOSURE

[002] The information in this section merely provides background information related to the present disclosure and may not constitute prior art(s) for the present disclosure.

[001] Internal combustion engines [further referred to as engines] are well known in the art. The internal combustion engines are provided to generate power through combusting fossil fuels. The engine is equipped with inlet valves and exhaust valves. A mixture of fossil fuel and air is fed into a combustion chamber of the engine when the inlet valve is opened. After combusting the fuel within the combustion chamber, the exhaust gases are released from the engine when the exhaust valve is opened. The opening or closing of inlet valves and outlet valves are operated through a camshaft of the engine. The camshaft is located within the head of the engine and coupled to a crankshaft of the engine. The camshaft rotates based on the rotary motion of the crankshaft to operate the inlet valves and the exhaust valves.

[002] Typically, the camshafts may be classified into two categories such as solid camshafts and hollow camshafts. The hollow camshafts may be utilized based on their advantages over the solid camshafts such as less weight that improves the overall engine efficiency. However, there are certain demerits associated with conventional hollow camshafts, for example the hollow camshafts have less rigidity compared to the solid camshafts, thereby the conventional hollow camshafts often deform due to bending stress generated within the hollow camshafts during the operation of the engine. Due to the bending of the hollow camshaft, the noise, vibration, and harshness are increased which affects the overall performance of the engine. This is not desired.

[003] The present disclosure is directed to overcome one or more limitations stated above or any other limitations associated with the prior art.

[004] The drawbacks/difficulties/disadvantages/limitations of the conventional techniques explained in the background section are just for exemplary purposes and the disclosure would never limit its scope only such limitations. A person skilled in the art would understand that this disclosure and below mentioned description may also solve other problems or overcome the other drawbacks/disadvantages of the conventional arts which are not explicitly captured above.

SUMMARY OF THE DISCLOSURE

[005] The one or more shortcomings of the prior art are overcome by configuration of a camshaft as claimed, and additional advantages are provided through the provision of the camshaft of an internal combustion engine as claimed in the present disclosure. Additional features and advantages are realized through the techniques of the present disclosure. Other embodiments and aspects of the disclosure are described in detail herein and are considered a part of the claimed disclosure.

[006] In one non-limiting embodiment of the present disclosure, a camshaft of an internal combustion engine may be disclosed. The camshaft comprises a tubular member and a plurality of collars. The tubular member may be configured to be rotatably mounted on a cylinder head of the internal combustion engine. The tubular member may be hollow and defined with a plurality of cams. The plurality of cams may be positioned at an outer surface of the tubular member. The plurality of collars encloses the tubular member and may be supported by support members defined within the head to allow rotation of the tubular member relative to the support members. The tubular member may be defined with a plurality of ribs to resist bending in the tubular member. The provision of ribs on the tubular member enhances the overall rigidity of the camshaft.

[007] In an embodiment of the present disclosure, the plurality of ribs may be positioned between at least one collar of the plurality of the collars and at least one cam of the plurality of the cams.

[008] In an embodiment of the present disclosure, the plurality of collars and the plurality of cams may be positioned along length of the tubular member such that at least one cam of the plurality of cams may be positioned between two collars of the plurality of collars.

[009] In an embodiment of the present disclosure, each cam of the plurality of cams may be defined with a cam heel and a cam lobe, wherein the cam heel may be cylindrically shaped and the cam lobe extends radially away from periphery of the cam heel.

[0010] In an embodiment of the present disclosure, at least one rib of the plurality of ribs extends from the outer surface of the tubular member along length of the tubular member towards a top end of the cam lobe.

[0011] In an embodiment of the present disclosure, at least one rib of the plurality of ribs extends from the outer surface of the tubular member along length of the tubular member towards an end of the cam heel opposite to the top end of the cam lobe. The ribs dampen the vibrations and improve the noise, vibration, and harshness [NVH] of the engine.

[0012] In an embodiment of the present disclosure, the plurality of ribs may be an integral part of the tubular member and the plurality of cams.

[0013] In an embodiment of the present disclosure, a drive member may be positioned at an end of the tubular member, wherein the drive member may be configured to be engaged with a crankshaft of the internal combustion engine.

[0014] It is to be understood that the aspects and embodiments of the disclosure described above may be used in any combination with each other. Several of the aspects and embodiments may be combined together to form a further embodiment of the disclosure.

[0015] 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 THE ACCOMPANYING DRAWINGS

[0016] The novel features and characteristics of the disclosure are set forth in the description. The disclosure itself, however, as well as a preferred mode of use, further objectives, and advantages thereof, will best be understood by reference to the following description of an illustrative embodiment when read in conjunction with the accompanying drawings. One or more embodiments are now described, by way of example only, with reference to the accompanying drawings wherein like reference numerals represent like elements and in which:

[0017] Figure 1 illustrates a front view of a camshaft of an internal combustion engine, according to an embodiment of the present disclosure.

[0018] Figure 2 illustrates a magnified view of Figure 1.

[0019] Figure 3 illustrates a cut-sectional view of Figure 1.

[0020] Figure 4 illustrates a magnified view of Figure 3.

[0021] Skilled artisans will appreciate that elements in the drawings are illustrated for simplicity and have not necessarily been drawn to scale. For example, the dimensions of some of the elements in the drawings may be exaggerated relative to other elements to help to improve understanding of embodiments of the present disclosure.

DETAILED DESCRIPTION

[0022] While the disclosure is susceptible to various modifications and alternative forms, specific embodiments thereof have been shown by way of example in Figures 1 to 4 and will be described in detail below. It should be understood, however, that it is not intended to limit the disclosure to the particular forms disclosed, but on the contrary, the disclosure is to cover all modifications, equivalents, and alternatives falling within the scope of the disclosure as defined by the appended claims.

[0023] Before describing detailed embodiments, the novelty and inventive step that are in accordance with the present disclosure reside in a camshaft of an internal combustion engine. It is to be noted that a person skilled in the art can be motivated by the present disclosure and modification of the camshaft. However, such modification should be construed within the scope of the present disclosure. Accordingly, the drawings show only those specific details that are pertinent to understanding the embodiments of the present disclosure so as not to obscure the disclosure with details that will be readily apparent to those of ordinary skill in the art having the benefit of the description herein.

[0024] In the present disclosure, the term “exemplary” is used herein to mean “serving as an example, instance, or illustration.” Any embodiment or implementation of the present subject matter described herein as “exemplary” is not necessarily to be construed as preferred or advantageous over other embodiments.

[0025] The terms “comprises”, “comprising”, or any other variations thereof, are intended to cover a non-exclusive inclusions, such that a device that comprises a list of components does not include only those components but may include other components not expressly listed or inherent to such device. In other words, one or more elements in a device proceeded by “comprises… a” does not, without more constraints, preclude the existence of other elements or additional elements in the device.

[0026] The terms like “at least one” and “one or more” may be used interchangeably or in combination throughout the description.

[0027] Embodiments of the present disclosure disclose a camshaft of an internal combustion engine that has high rigidity. Generally, the hollow camshafts have less rigidity compared to the solid camshafts, thereby the conventional hollow camshafts often deform due to bending stress generated within the hollow camshafts during the operation of the engine. Due to the bending of the hollow camshaft, the noise, vibration, and harshness are increased which affects the overall performance of the engine.

[0028] Accordingly, a camshaft of the present disclosure may be adapted to enhance rigidity and aid in improving noise, vibration, and harshness [NVH] of the internal combustion engine. The camshaft comprises a tubular member and a plurality of collars. The tubular member may be configured to be rotatably mounted on a cylinder head of the internal combustion engine. The tubular member may be hollow and defined with a plurality of cams. The plurality of cams may be positioned at an outer surface of the tubular member. The plurality of collars encloses the tubular member and may be supported by support members defined within the cylinder head to allow rotation of the tubular member relative to the support members. The tubular member may be defined with a plurality of ribs to resist bending in the tubular member. The provision of ribs on the outer surface of the tubular member enhances the overall rigidity of the camshaft. Further, the ribs enhance the rigidity and dampen the vibrations to improve the noise, vibration, and harshness [NVH] of the engine. Furthermore, this configuration of the camshaft of the present disclosure may be simple, and easy to manufacture.

[0029] Reference will now be made to the exemplary embodiments of the disclosure, as illustrated in the accompanying drawings. Wherever possible, the same numerals will be used to refer to the same or like parts. Embodiments of the disclosure are described in the following paragraphs with reference to Figures 1 to 4. In Figures 1 to 4, the same element or elements that have the same functions are indicated by the same reference signs.

[0030] Referring to Figure 1, which illustrates a front view of a camshaft (100) of an internal combustion engine [not shown in Figures]. The internal combustion engine may be referred hereinafter as to an engine. The camshaft (100) may be configured to be positioned within a cylinder head [not shown in Figures] of the engine. Alternatively, the camshaft (100) may be positioned at a place, other than the cylinder head, within the engine, without limiting the scope of the present disclosure. The camshaft (100) may be supported by one or more support members [not shown in Figures] provided within the cylinder head. The support members may be an integral part of the cylinder head and may be coupled to collar caps to form a cavity [not shown in Figures]. The cavity may be formed to accommodate the camshaft (100) therein. The camshaft (100) may be coupled to a crankshaft [not shown in Figures] of the engine. The camshaft (100) may be configured to operate inlet valves and outlet valves [not shown in Figures] of the engine based on the rotary motion of the crankshaft of the engine.

[0031] Referring further to Figure 1, the camshaft (100) comprises a tubular member (10). The tubular member (10) may be an elongated member that may be hollow at centre. The tubular member (10) may be positioned within the cylinder head of the engine such that an end of the tubular member (10) extends outwardly from the head of the engine. The camshaft (100) may include a drive member that may be positioned at the said extended end of the tubular member (10). The drive member may be a cam gear or a pulley that may be coupled to the crankshaft of the engine through the meshing of gears or the belt drive, without limiting the scope of the present disclosure. Accordingly, the camshaft (100) rotates based on the rotary motion of the crankshaft of the engine.

[0032] Referring to Figure 2, the tubular member (10) includes a plurality of cams (20). The plurality of cams (20) may be positioned on an outer surface (10a) of the tubular member (10). The plurality of cams (20) may be positioned along length of the outer surface of tubular member (10a) and define a certain gap between each consecutive cams (20) as per functional requirements. The plurality of cams (20) may be configured to selectively either directly engaged with the inlet valves and exhaust valves or indirectly engaged with the inlet valves and the exhaust valves through a plurality of rockers [not shown in Figures]. The plurality of cams (20) may be rotatable along with the rotation of the tubular member (10). In an embodiment, each cam of the plurality of cams (20) includes a cam heel (20a) and a cam lobe (20b). The cam heel (20a) may be shaped as a hollow cylinder that encloses a portion of the tubular member (10). The cam lobe (20b) may be referred to as a raised portion that extends radially away from periphery of the cam heel (20a). When the cam heel (20a) is in contact with the valves or rockers, the valves remain in a closed position and when the cam lobe (20b) is in contact with the valves or rockers, the valves are in an opened position.

[0033] Referring to Figure 3, the camshaft (100) includes a collar (30). The collar (30) may be positioned on the outer surface (10a) of the tubular member (10). The collar (30) may be positioned along length of the tubular member (10). The collar (30) may enclose the tubular member (10) and may be supported by the support members. The collars (30) may be thrust collars (30), without limiting the scope of the present disclosure. The collars (30) may be configured to allow rotation of the tubular member (10) relative to the support members.

[0034] Referring to Figures 1 and 3, the tubular member (10) may be defined with a plurality of ribs (R). The plurality of ribs (R) may be formed on the outer surface (10a) of the tubular member (10). The plurality of ribs (R) may be positioned between collar (30) and at least one cam of the plurality of the cams (20). In an embodiment, at least one rib of the plurality of ribs (R) extends from the outer surface (10a) of the tubular member (10) along length of the tubular member (10) towards a top end of the cam lobe (20b) and at least one rib of the plurality of ribs (R) extends from the outer surface (10a) of the tubular member (10) along length of the tubular member (10) towards an end of the cam heel (20a). The said end of the cam heel (20a) may be positioned opposite to the top end of the cam lobe (20b). The plurality of ribs (R) may be configured to resist bending in the tubular member (10) and enhance the rigidity of the tubular member (10). This configuration of the ribs (R) dampens vibrations generated within the tubular member (10) and aids in improving the noise, vibrations, and harshness [NVH] of the engine.

[0035] Referring further to Figure 4, the plurality of ribs (R) may be an integral part of the outer surface of tubular member (10a) and the plurality of cams (20). The ribs (R) may have a trapezoidal shape. The trapezoidal shaped ribs (R) may have a higher sectional area, which aids in absorbing more vibrations generated within the tubular member (10) and increases the overall rigidity of the camshaft (100).

[0036] In accordance with the present disclosure, the camshaft (100), as explained in the above paragraphs, may be adapted to increase rigidity. Further, the camshaft (100) of the present application dampens the vibrations and aids in improving the noise, vibration, and harshness [NVH] of the engine. Further, the camshaft (100) of the present disclosure may be simple, and easy to manufacture.

[0037] The various embodiments of the present disclosure have been described above with reference to the accompanying drawings. The present disclosure is not limited to the illustrated embodiments; rather, these embodiments are intended to fully and completely disclose the subject matter of the disclosure to those skilled in this art. In the drawings, like numbers refer to like elements throughout. The thicknesses and dimensions of some components may be exaggerated for clarity.

[0038] LIST OF REFERENCE NUMERALS
Sr. No. Description
100 Camshaft
10 Tubular member
10a Outer surface
20 Plurality of cams
20a Cam heel
20b Cam lobe
30 collar
40 Holes
50 Keyway
R Ribs

[0039] EQUIVALENTS:

The embodiments herein and the various features and advantageous details thereof are explained with reference to the non-limiting embodiments in the description. Descriptions of well-known components and processing techniques are omitted so as to not unnecessarily obscure the embodiments herein. The examples used herein are intended merely to facilitate an understanding of ways in which the embodiments herein may be practiced and to further enable those of skill in the art to practice the embodiments herein. Accordingly, the examples should not be construed as limiting the scope of the embodiments herein.
The foregoing description of the specific embodiments will so fully reveal the general nature of the embodiments herein that others can, by applying current knowledge, readily modify and/or adapt for various applications such specific embodiments without departing from the generic concept, and, therefore, such adaptations and modifications should and are intended to be comprehended within the meaning and range of equivalents of the disclosed embodiments. It is to be understood that the phraseology or terminology employed herein is for the purpose of description and not of limitation. Therefore, while the embodiments herein have been described in terms of preferred embodiments, those skilled in the art will recognize that the embodiments herein can be practiced with modification within the scope of the embodiments as described herein.
Any discussion of documents, acts, materials, devices, articles and the like that has been included in this specification is solely for the purpose of providing a context for the disclosure. It is not to be taken as an admission that any or all of these matters form a part of the prior art base or were common general knowledge in the field relevant to the disclosure as it existed anywhere before the priority date of this application.

The numerical values mentioned for the various physical parameters, dimensions or quantities are only approximations and it is envisaged that the values higher/lower than the numerical values assigned to the parameters, dimensions or quantities fall within the scope of the disclosure, unless there is a statement in the specification specific to the contrary. , Claims:We claim:
1. A camshaft (100) of an internal combustion engine, the camshaft (100) comprising:
a tubular member (10) configured to be rotatably mounted on a cylinder head of the internal combustion engine, the tubular member (10) is hollow and defined with a plurality of cams (20), wherein the plurality of cams (20) are positioned at an outer surface (10a) of the tubular member (10);
a collar (30) enclosing the tubular member (10) and supported by support members defined within the cylinder head to allow rotation of the tubular member (10) relative to the support members, wherein the tubular member (10) is defined with a plurality of ribs (R) to resist bending in the tubular member (10).

2. The camshaft (100) as claimed in claim 1, wherein the plurality of ribs (R) are positioned between collar (30) and at least one cam of the plurality of the cams (20).

3. The camshaft (100) as claimed in claim 1, wherein the plurality of collars (30) and the plurality of cams (20) are positioned along length of the tubular member (10) such that at least one cam of the plurality of cams (20) is positioned between two collars (30) collar (30).

4. The camshaft (100) as claimed in claim 1, wherein each cam of the plurality of cams (20) is defined with a cam heel (20a) and a cam lobe (20b), wherein the cam heel (20a) is cylindrically shaped and the cam lobe (20b) extends radially away from periphery of the cam heel (20a).

5. The camshaft (100) as claimed in claim 1, wherein at least one rib of the plurality of ribs (R) extends from the outer surface (10a) of the tubular member (10) along length of the tubular member (10) towards a top end of the cam lobe (20b).

6. The camshaft (100) as claimed in claim 5, wherein at least one rib of the plurality of ribs (R) extends from the outer surface (10a) of the tubular member (10) along length of the tubular member (10) towards an end of the cam heel (20a) opposite to the top end of the cam lobe (20b).

7. The camshaft (100) as claimed in claim 1, wherein the plurality of ribs (R) are an integral part of the outer surface of tubular member (10a) and the plurality of cams (20).

8. The camshaft (100) as claimed in claim 1, comprising a drive member positioned at an end of the tubular member (10), wherein the drive member is configured to be engaged with a crankshaft of the internal combustion engine.