DESC:TECHNICAL FIELD OF THE INVENTION
[001] The present invention relates to an internal combustion (IC) engine and, more particularly to internal combustion engine with reduced noise, vibrations and harshness.

BACKGROUND OF THE INVENTION
[002] IC engines have vast applications in automotive, marine, aircraft, industrial power, and other portable machinery like lawnmowers, string trimmers, chain saws, leaf blowers, pressure washers.
[003] Referring Figure 1 shows a conventional IC engine (100) with components mainly including an engine block (109) with engine cylinders in bores (110), a crankshaft for converting linear motion of a piston into rotational motion, piston with piston rings placed in the engine cylinders, a connecting rod for connecting piston at one end and crankshaft at the other end, a camshaft (101) mounted on to a cylinder head (102) of the engine (100), a lubrication system having passage ways and an engine oil sump casing which retains lubricating oil.
[004] Based on engine design layouts, there may be a single overhead cam (SOHC) and double overhead cam (DOHC). Front end of the camshaft takes drive from a chain drive (103) and rotates cam lobes integrated along its length. The cam lobes push against the inlet and outlet valves to open and close them at specific time within the engine combustion cycle. The inlet valve is opened to take the air into the cylinder and outlet valve is opened to leave exhaust gases from the cylinder. The closing of the valves takes place because of a spring mechanism.
[005] The camshaft lobes in rotation may be susceptible to operating loads. In order to counter the loads and provide stability to the camshaft, journals are provided on a base of the camshaft at places which are not occupied by the cam lobes and bearings (105) may be mounted on the journals exactly between the cam lobes of two different cylinder valves. For example, 4-cylinder engine may have 6 bearings (105) maximum on either side of the cam lobes corresponding to the 4-cylinders. Bearings (105) may be provided with bearing caps (106) on the upper half and bolted to the cylinder head (102) at the lower half, thereby providing support to the camshaft (101).
[006] Rear end of the camshaft (101) comprises a fuel injection pump (FIP) lobe that while rotating pushes against a roller of the fuel injection pump (FIP) (107) so as to supply fuel into the cylinders. Therefore, the camshaft (101) drives the fuel injection pump (107) (FIP) with a roller mechanism, which may be housed (108) and bolted to the cylinder head (102).
[007] The bearings (105) provide support along the length of the camshaft (101) in such a manner that the operating loads are equally shared. However, noise and vibrations are still observed in the engine (100). Further, it is also observed that the FIP lobe is overhung causing flexing, wear and failure of the camshaft (101).
[008] Therefore, there is a need to overcome one or more abovementioned drawbacks.

SUMMARY OF THE INVENTION
[009] Accordingly, an aspect of the present invention discloses an internal combustion (IC) engine having an engine block with a plurality of cylinders, a crankshaft, a plurality of connecting rods, a plurality of pistons, and a lubrication system, said internal combustion engine comprises a plurality of cam lobes and a plurality of journals disposed along axial length of a camshaft mounted on to a cylinder head of the engine; a plurality of bearings with bearing caps mounted on the journals between the cam lobes of two different cylinder valves for providing support along the axial length of the camshaft; and a fuel injection pump (FIP) housing provided at a rear end of the camshaft, wherein a rear end journal of the camshaft integrated with a fuel injection pump lobe extends along inner cavity of said FIP housing having a plurality of ribs with raised surfaces; said FIP housing inner cavity surmounts a bearing deposited therein that provides support and prevents flexing, wear and failure of the camshaft; and said lubrication system includes passageways for lubricating and minimizing friction between rotating said rear end journal integrated with the FIP lobe and said stationary bearing inside the FIP housing, thereby reducing noise, vibration and harshness (NVH) of the engine.
[0010] According to an embodiment, height of the raised surfaces of the plurality of ribs matches with the outer diameter of the journal integrated FIP lobe.
[0011] According to another aspect, the present invention discloses a method for a method for reducing noise, vibration and harshness of an internal combustion engine comprising the steps of:
a) integrating a journal to a fuel injection pump lobe at a rear end of a camshaft;
b) providing a bearing inside an inner cavity of a fuel injection pump (FIP) housing;
c) providing said inner cavity with a plurality of ribs with raised surfaces that acts as bearing support, thereby prevents flexing, wear and failure of the camshaft; and
d) providing a lubrication system having passageways for lubricating and minimizing friction between rotating journal integrated with the FIP lobe and said stationary bearing inside the FIP housing, thereby reducing noise, vibration and harshness (NVH) of the engine.
[0012] According to still another aspect, the present invention discloses a camshaft assembly for an internal combustion engine comprising a camshaft extending in an axial direction mounted on to a cylinder head of the engine; a plurality of cam lobes and a plurality of journals disposed along axial length of the camshaft; a plurality of bearings with bearing caps mounted on the journals between the cam lobes of two different cylinder valves for providing support along the axial length of the camshaft; and a rear end journal of the camshaft integrated with a fuel injection pump lobe extending along inner cavity of a fuel injection pump (FIP) housing having a plurality of ribs with raised surfaces.
[0013] According to yet another aspect, the present invention discloses supporting system for a rear end of a camshaft mounted on to a cylinder head of an internal combustion engine, said supporting system comprising an inner cavity of a fuel injection pump (FIP) housing having a plurality of ribs with raised surfaces; a bearing deposited inside said inner cavity for providing support to a rear end journal of the camshaft integrated with a fuel injection pump lobe, thereby preventing flexing, wear and failure of the camshaft.
[0014] According to a further aspect, the present invention discloses fuel injection pump (FIP) housing for an internal combustion engine, said FIP housing comprising an inner cavity having a plurality of ribs with raised surfaces; a bearing deposited inside said inner cavity for providing support to a rear end journal of a camshaft integrated with a fuel injection pump lobe, thereby preventing flexing, wear and failure of the camshaft; and at least one passageway for lubricating and minimizing friction between rotating said rear end journal integrated with the FIP lobe and said stationary bearing inside the FIP housing, thereby reducing noise, vibration and harshness (NVH) of the engine.

BRIEF DESCRIPTION OF THE DRAWINGS
The above and other aspects, features, and advantages of certain exemplary embodiments of the present invention will be more apparent from the following description taken in conjunction with the accompanying drawings in which:
Figure 1 is an isometric view showing a conventional engine;
Figure 2 is a front elevational view of a camshaft according to the aspect of the present invention;
Figure 3 is a cross sectional front view of a FIP housing having a journal integrated with a fuel injection pump lobe, a camshaft bearing support and a lubrication system having passageways according to the embodiment present invention;
Figure 4 is a front view of the fuel injection pump (FIP) housing showing inner cavity according to the embodiment present invention;
Figure 5 is an isometric view of the camshaft with the journal integrated FIP cam lobe, according to the present invention; and
Figure 6 is a cross sectional front view of the camshaft with the journal integrated FIP cam lobe according to the present invention.
Persons skilled in the art will appreciate that elements in the figures are illustrated for simplicity and clarity and may have not been drawn to scale. For example, the dimensions of some of the elements in the figure may be exaggerated relative to other elements to help to improve understanding of various exemplary embodiments of the present disclosure.
Throughout the drawings, it should be noted that like reference numbers are used to depict the same or similar elements, features, and structures.

DETAILED DESCRIPTION OF THE INVENTION
[0015] In general, the present invention discloses a rear end journal of a camshaft integrated with a fuel injection pump lobe extending along an inner cavity of fuel injection pump (FIP) housing having a plurality of ribs with raised surfaces. The FIP housing inner cavity surmounts a bearing deposited therein thereby provides support and prevents flexing, wear and failure of the camshaft. The FIP housing includes at least one passageway for lubricating and minimizing friction between rotating said rear end journal integrated with the FIP lobe and said stationary bearing inside the FIP housing, thereby reducing noise, vibration and harshness (NVH) of the engine.
[0016] According to the present invention, the internal combustion engine comprises a plurality of cam lobes and a plurality of journals disposed along axial length of a camshaft mounted on to a cylinder head of the engine. A plurality of bearings with bearing caps mounted on the journals between the cam lobes of two different cylinder valves provides support along the axial length of the camshaft.
[0017] According to the present invention, the plurality of cam lobes and the journal integrated with fuel injection pump lobe actuates inlet and outlet valves and a fuel injection pump that supply fuel into the cylinders. A fuel injection pump (FIP) housing surmount the fuel injection pump (FIP) lobe at a rear end of the camshaft.
[0018] According to the present invention, the journal integrated with the FIP lobe may have an outer diameter to match the diameter of the inner cavity of the FIP housing with enough clearances provided therein for lubrication and extends along the length of rear end of the camshaft.
[0019] According to the present invention, the plurality of ribs in an inner cavity of the FIP housing may have raised surfaces to a height to match with the outer diameter of the journal integrated FIP lobe. The plurality of ribs may provide support to the bearing provided in the FIP housing. The plurality of ribs may extend along the cavity of the FIP housing covering a total length of the journal extended therein.
[0020] The number of the bearings assembled onto the camshaft is limited by the available space in the cylinder head and to provide any additional bearing support so as to counter the operating loads on camshaft, it requires inclusion of numerous components and increases the length of the camshaft and the cylinder head which further results into increased cost and weight of the engine. Therefore, the present invention provides an additional bearing at the rear end of a camshaft in the FIP housing without increasing the length of a cylinder head or the camshaft or inclusion of any another additional component.
[0021] According to the present invention, the additional journal integrated with the FIP lobe performs the dual duty, firstly by acting as a journal and secondly by actuating the fuel injection pump through roller follower.
[0022] According to the present invention, the cavity of the FIP housing performs the dual duty of providing bearing support and also acting as a housing for the fuel injection pump (FIP) where enough clearances may be provided between the extended FIP lobe and the plurality of raised ribs to avoid any friction during the rotation of the FIP lobe.
[0023] According to the present invention, the integrated FIP lobe with journal and the FIP housing with bearing, raised surfaces provides enough support required to prevents flexing, wear and failure of the camshaft and reduces the noise, vibration and harshness (NVH) of the engine, thereby improving the NVH characteristics of the engine.
[0024] According to another aspect, a method for a method for reducing noise, vibration and harshness of an internal combustion engine comprising the steps of:
a) integrating a journal to a fuel injection pump lobe at a rear end of a camshaft;
b) providing a bearing inside an inner cavity of a fuel injection pump (FIP) housing;
c) providing said inner cavity with a plurality of ribs with raised surfaces that acts as bearing support, thereby prevents flexing, wear and failure of the camshaft; and
d) providing a lubrication system having passageways for lubricating and minimizing friction between rotating journal integrated with the FIP lobe and said stationary bearing inside the FIP housing, thereby reducing noise, vibration and harshness (NVH) of the engine.
[0025] According to the present invention, the integrated FIP lobe with journal may be adapted to any length of camshaft at rear end.
[0026] According to the present invention, the integrated FIP lobe with journal and the FIP housing may be adapted to all IC engines.
[0027] According to the present invention, the components of the engine may be made of materials known in the art.
Other aspects, advantages, and salient features of the invention will become apparent to those skilled in the art from the following detailed description, which, taken in conjunction with the annexed drawings, discloses exemplary embodiments of the invention.
The following description with reference to the accompanying drawings is provided to assist in a comprehensive understanding of exemplary embodiments of the invention as defined by the claims and their equivalents. It includes various specific details to assist in that understanding but these are to be regarded as merely exemplary. Accordingly, those of ordinary skill in the art will recognize that various changes and modifications of the embodiments described herein can be made without departing from the scope and spirit of the invention. In addition, descriptions of well-known functions and constructions are omitted for clarity and conciseness.
The terms and words used in the following description and claims are not limited to the bibliographical meanings, but, are merely used by the inventor to enable a clear and consistent understanding of the invention. Accordingly, it should be apparent to those skilled in the art that the following description of exemplary embodiments of the present invention are provided for illustration purpose only and not for the purpose of limiting the invention as defined by the appended claims and their equivalents.
Figures discussed below, and the various embodiments used to describe the principles of the present disclosure in this patent document are by way of illustration only and should not be construed in any way that would limit the scope of the disclosure. Those skilled in the art will understand that the principles of the present disclosure may be implemented in any suitably arranged environment. The terms used to describe various embodiments are exemplary. It should be understood that these are provided to merely aid the understanding of the description, and that their use and definitions in no way limit the scope of the invention.
[0028] Referring Figure 1 shows a shows an isometric view showing the conventional engine with a camshaft (101) mounted on a cylinder head (102) and a chain drive (103) connected to front end of an engine (100) and a fuel injection drive (104) connected to rear end of the engine (100). Bearings (105) mounted on cylinder head (102) and may be supported with bearing caps (106) on the upper side and bolted to the cylinder head (102) at the lower side. A fuel injection pump (FIP pump) (107) may be housed (108) at the rear end of the engine (100). The camshaft (101) includes a plurality of journals and a plurality of cam lobes integrated along its length. The bearings are mounted on the journals exactly between the cam lobes of two different cylinder valves.
[0029] Referring Figure 2 shows a front elevational view of the camshaft (201) with 7 journals (202) and cam lobes (203) adapted across the length for a 4-cylinder engine (200) (not shown) according to the present invention. A fuel injection pump lobe (204) may be placed at rear end of the engine (200) according to the present invention. The cam lobes (203) in rotation assist in opening and closing of the valves (not shown). The FIP lobe (204) through roller follower actuates the fuel injection pump housed inside FIP housing (205) to inject the fuel into the cylinder of the engine (200).
[0030] Referring Figure 3 shows FIG. 3 shows a cross sectional front view of the FIP housing (205), a rear end layout of the engine (200) with the camshaft (201), the journal (202) integrated with fuel injection pump lobe (204), a bearing support (206) and a lubrication system having passageways (207) in the FIP housing (205) according to the present invention. The FIP lobe (204) extends along the length of rear end of the camshaft (201). The extended length is supported by the bearing in the FIP housing (205). Therefore, the additional support required to avoid / reduce wear and failure of the camshaft (201) is provided by the FIP housing (205). The passageways (207) carry lubricating oil into the bearing support (206) to reduce friction between the extended FIP lobe (204) and the FIP housing (205).
[0031] Referring Figure 4 shows a front view of the fuel injection pump (FIP) housing (205), the inner cavity of the FIP housing (205) with plurality of additional ribs (206) that extend along the surface of the extended FIP lobe (204) and provides support to the FIP lobe (204).
[0032] According to the embodiment, the present invention discloses a supporting system for a rear end of a camshaft mounted on to a cylinder head of an internal combustion engine comprises an inner cavity of a fuel injection pump (FIP) housing (205) having a plurality of ribs (206) with raised surfaces; a bearing deposited inside said inner cavity for providing support to a rear end journal (202) of the camshaft integrated with a fuel injection pump lobe (204), thereby preventing flexing, wear and failure of the camshaft (201).
[0033] According to the embodiment, the present invention discloses fuel injection pump (FIP) housing (205) for an internal combustion engine, said FIP housing comprises an inner cavity having a plurality of ribs (206) with raised surfaces; a bearing deposited inside said inner cavity for providing support to a rear end journal (202) of a camshaft integrated with a fuel injection pump lobe (204), thereby preventing flexing, wear and failure of the camshaft; and at least one passageway (207) for lubricating and minimizing friction between rotating said rear end journal integrated with the FIP lobe and said stationary bearing inside the FIP housing, thereby reducing noise, vibration and harshness (NVH) of the engine.
[0034] Referring Figure 5 shows an isometric view of the camshaft (201) with the journal (202) integrated FIP cam lobe (204), according to the present invention.
[0035] According to the embodiment, the present invention discloses camshaft assembly for an internal combustion engine comprising a camshaft (201) extending in an axial direction; a plurality of cam lobes (203) and a plurality of journals (202) disposed along axial length of the camshaft (201) mounted on to a cylinder head of the engine; a plurality of bearings (105) with bearing caps (106) mounted on the journals (202) between the cam lobes (203) of two different cylinder valves for providing support along the axial length of the camshaft (201); and a rear end journal (202) of the camshaft integrated with a fuel injection pump lobe (204) extending along inner cavity of a fuel injection pump (FIP) housing (205) having a plurality of ribs with raised surfaces.
[0036] Referring Figure 6 is a cross sectional front view of the camshaft (201) with the journal (202) integrated FIP cam lobe (204), according to the present invention.
[0037] The present invention has been described in the context of internal combustion engine comprising a camshaft having a plurality of cam lobes and a journal integrated with fuel injection pump (FIP) lobe disposed along axial length of the shaft for actuating inlet and outlet valves. However, the camshaft with journal integrated FIP lobe and the FIP housing with bearing and plurality of ribs with raised surfaces of the present invention can be used in any type of engines such that it prevents flexing, wear and failure of the camshaft and reducing noise, vibration and harshness (NVH) of the engine. The disclosed present invention may be modified within the scope and may be used in other engines.
[0038] In the foregoing detailed description of aspects embodiments of the invention, various features are grouped together in a single embodiment for the purpose of streamlining the disclosure. This method of disclosure is not to be interpreted as reflecting an intention that the claimed embodiments of the invention require more features than are expressly recited in each claim. Rather, as the following claims reflect, inventive subject matter lies in less than all features of a single disclosed embodiment. Thus, the following claims are hereby incorporated into the detailed description of aspects, embodiments of the invention, with each claim standing on its own as a separate embodiment.
[0039] It is understood that the above description is intended to be illustrative, and not restrictive. It is intended to cover all alternatives, modifications and equivalents as may be included within the spirit and scope of the invention as defined in the appended claims. Many other embodiments will be apparent to those of skill in the art upon reviewing the above description. The scope of the invention should, therefore, be determined with reference to the appended claims, along with the full scope of equivalents to which such claims are entitled. In the appended claims, the terms “including” is used as the plain-English equivalent of the respective term “comprising” respectively.

,CLAIMS:
1. An internal combustion (IC) engine (200) having an engine block (109) with a plurality of cylinders, a crankshaft, a plurality of connecting rods, a plurality of pistons, and a lubrication system, said internal combustion engine comprising:
a plurality of cam lobes (203) and a plurality of journals (202) disposed along axial length of a camshaft (201) mounted on to a cylinder head (102) of the engine (200);
a plurality of bearings (105) with bearing caps (106) mounted on the journals (202) between the cam lobes (203) of two different cylinder valves for providing support along the axial length of the camshaft (201); and
a fuel injection pump (FIP) housing (205) provided at a rear end of the camshaft (201), wherein
a rear end journal (202) of the camshaft (201) integrated with a fuel injection pump lobe (204) extends along inner cavity of said FIP housing (205) having a plurality of ribs with raised surfaces (206);
said FIP housing (205) inner cavity surmounts a bearing deposited therein that provides support and prevents flexing, wear and failure of the camshaft; and
said lubrication system includes passageways (207) for lubricating and minimizing friction between rotating said rear end journal (202) integrated with the FIP lobe (204) and said stationary bearing inside the FIP housing (205), thereby reducing noise, vibration and harshness (NVH) of the engine.

2. The internal combustion (IC) engine (200) as claimed in claim 1, wherein height of the raised surfaces of the plurality of ribs (206) matches with the outer diameter of the journal (202) integrated FIP lobe (204).

3. A method for a method for reducing noise, vibration and harshness of an internal combustion engine (200) comprising the steps of:
a) integrating a journal (202) to a fuel injection pump lobe (204) at a rear end of a camshaft (201);
b) providing a bearing inside an inner cavity of a fuel injection pump (FIP) housing (205);
c) providing said inner cavity with a plurality of ribs with raised surfaces (206) that acts as bearing support, thereby prevents flexing, wear and failure of the camshaft (201); and
d) providing a lubrication system having passageways (207) for lubricating and minimizing friction between rotating journal (202) integrated with the FIP lobe (204) and said stationary bearing inside the FIP housing (205), thereby reducing noise, vibration and harshness (NVH) of the engine.

4. A camshaft assembly for an internal combustion engine (200) comprising:
a camshaft (201) extending in an axial direction mounted on to a cylinder head of the engine;
a plurality of cam lobes (203) and a plurality of journals (202) disposed along axial length of the camshaft (201);
a plurality of bearings (105) with bearing caps (106) mounted on the journals (202) between the cam lobes (203) of two different cylinder valves for providing support along the axial length of the camshaft (201); and
a rear end journal (202) of the camshaft integrated with a fuel injection pump lobe (204) extending along inner cavity of a fuel injection pump (FIP) housing (205) having a plurality of ribs with raised surfaces (206).

5. A supporting system for a rear end of a camshaft (201) mounted on to a cylinder head of an internal combustion engine (200), said supporting system comprising:
an inner cavity of a fuel injection pump (FIP) housing (205) having a plurality of ribs with raised surfaces (206);
a bearing deposited inside said inner cavity for providing support to a rear end journal (202) of the camshaft (201) integrated with a fuel injection pump lobe (204), thereby preventing flexing, wear and failure of the camshaft (201).

6. A fuel injection pump (FIP) housing (205) for an internal combustion engine (200), said FIP housing (205) comprising:
an inner cavity having a plurality of ribs with raised surfaces (206);
a bearing deposited inside said inner cavity for providing support to a rear end journal (202) of a camshaft (201) integrated with a fuel injection pump lobe (204), thereby preventing flexing, wear and failure of the camshaft; and
at least one passageway (207) for lubricating and minimizing friction between rotating said rear end journal (202) integrated with the FIP lobe (204) and said stationary bearing inside the FIP housing (205), thereby reducing noise, vibration and harshness (NVH) of the engine (200).