DESC:FORM – 2

THE PATENTS ACT, 1970
(39 OF 1970)

COMPLETE SPECIFICATION
(Section 10, rule 13)

“AN IMPROVED BEARING CAP”

Sintercom India Ltd
Indian Company registered under the Companies Act 2013
Having Address at
Gate No. 127, At post Mangrul, Tal Maval,
Pune, Maharashtra; India- 410507

The following specification particularly describes the nature of the invention and the manner in which it is to be performed:
Field of Invention:
The Present invention provides an improved bearing cap. In particular it relates to an invention that makes the repositioning of the bearing cap easy by eliminating the selective assembly of the bearing cap.
Background of Invention:
In an engine block, the part of the engine that the crankshaft runs through is split. Once the main caps are removed, the crankshaft can be set in the block on top of one-half of the main bearings. The other half of the main bearings are in the bearing cap and are placed in order onto the crankshaft and the corresponding other half of the main saddle. The bolts are then torqued to specification, thereby holding the crankshaft in place.

The crankshaft rotates within engine block through the use of main bearings. Supporting bore for main bearings are formed with half of bore in engine block and other half in bearing cap. Journal bearings are typically held in place by bearing caps which are bolted on engine block. Two bolts per cap are most common. The first and second end portions of the bearing cap include laterally outwardly extending flanged feet having end faces which mate with corresponding surfaces on the engine block.

Referring to Fig 1, illustrates the function of bearing cap in the engine block (13) in general. Said bearing cap (14) is the semicircular structure, with each side of said structure having extended feet like structure (19). Said engine bock (13) has threaded holes (17). The bearing cap (14) is attached to engine block (13) by bolting through bolt holes (21). The foot faces (16) mate with corresponding faces (15) of engine block (13). Supporting bore (18) for rotary shaft is formed by half semicircular shape in bearing cap (14) and another half in semicircular structure in said engine block (13). For the efficient working of the engine it is very important to ensure the vibration free and frictionless rotation of the shaft. It is also important that bearing cap (14) is fitted to its original position after reinstallation. Any deviation from original position creates out round condition which leads to vibration, friction and noise.

Repositioning of the bearing cap onto engine block after bore machining carried out is very important. Any deviation from original position will create out of round condition which leads to noise, knocking and vibration in the engine. There is a need of improvement. The bearing cap has to be repositioned after the machining is done. Conventionally the repositioning was selective assembly that the number of the bearing cap machined had to be repositioned in the same slot that is machined or else it caused misalignment. This misalignment causes noise, knocking and vibration in the engine.

There are many conventional bearing caps used to reposition the bearing cap on engine block without any misalignment. One such conventional structure is shown in fig. 2 where bearing caps are precisely machined to achieve close controlled width W. also engine block is machined to produce slot P. Controlled interference fit is maintained between cap and block. In this structure the bearing cap (14) is machined to achieve close controlled width W. Similarly, the engine block (13) is machined to produce slot P. Controlled interference fit is maintained between bearing cap feet (19) and engine block slot face (22).

Still, this type of bearing cap (14) is not reliable as the bolt holes (21) are responsible to align the cap bearing (14) in axial direction and since there is clearance between bolt (20) and bolt hole (21) the relocation is poor if bearing cap (14) shifts in axial direction. Also the interference fit maintained between width W and slot P is variable which affects the roundness of bore after refitting. The higher interference fit between bearing cap (14) and engine block (13) generates stresses in bearing cap (14) which get relieved in further installation process which creates out round condition of bore (18). On the other hand if interference fit between bearing cap (14) and engine block (13) is less than bearing cap (14) is loosely located on engine block (13). The structure does not relocate in axial direction; also the precision machining operations required on the main bearing caps to define the snap width W and on the engine block (13) to form the slot P, so as to avoid an overstressed or loose main bearing cap (14) in this structure, are relatively expensive.

Another conventional bearing cap repositioning is done through doweling as shown in Fig.3. It uses the precision dowels (23). For relocating bearing cap, these dowels are pressed in counter bores (24) of engine block (13). The dowels then locate in precisely machined counter bores (25) in the corresponding main bearing cap foot sections. The accuracy of installation of the dowels is dependent upon the precision counter boring of the engine block (13) and the main bearing cap (14).Both of these operations have a finite tolerance which, when stacked up with the tolerance on the dowel (23) outer diameter, can produce an unacceptable variation in location of the main bearing cap (14). This incurs additional cost of purchasing precision dowels (23), their handling and installation, and the costly machining of precision bores (24) (25) in the Engine block and main bearing caps (14).

Yet another type of conventional bearing cap (14) as shown in Fig 4 has a protrusion (28) on each foot face (16). This protrusion (28) produces indentation on corresponding face on engine block. Said protrusion (28) however does not have relief at face and also protrusion (28) has large width along with flat face at top that requires more force to produce indentation in engine block. Only two protrusions are used for relocating. Further said protrusions (28) are not relative to bolt hole (21). In actual, during machining said bearing cap (14) is mounted on the engine block (13) using bolts passing through the bolt hole (21); thus bolt holes (21) are responsible for alignment. So the accuracy of relocating is poor and also there is possibility of out round condition which will create noise and vibration.

Prior Arts and Its Disadvantages
A French patent FR3051234B1 relates primarily to a method of reinforcing an assembly for a heat engine comprising with reference to Fig. 5: - a cylinder block (13), and - at least one bearing cap (14) having a contact surface (16) intended to abut against a corresponding contact surface (15) of said cylinder block (13) so as to delimit a bearing when said bearing cap (14) and said cylinder block (13) are in assembled condition, said bearing being adapted to receive a section of a crankshaft, characterized in that said method comprises: - a step of friction-kneading reinforcement of said contact surface (15) of said crankcase (13), and - a step of producing a female cavity (28) in said contact surface (15) of said cylinder block (13).
However, the boss (26) is structured like 'cotton swab' having a central portion of constant section with two ends of large section. It has been observed that large section at the two ends is relatively blunt. They exert more pressure than central portion which results into excess mechanical stress at the end of cavity. Observe an appearance of cracks in the assembly area at the end of indentation cavity likely to cause breakage of the engine.

With reference to Fig 6 A PCT application PCT/US97/04050 discloses bearing cap (14) made from sintered powder metal has integrally formed tapered bosses (26) surrounding its bolt holes (21) which extend into counter bores (L) (24) in the engine bearing bulkhead structure (B) (13) and produce plastic conformance between the bosses (26) and the bulkhead (B) (13) when the boss (26) is seated in the counter bore (L) (24). The bearing cap (14) can then be removed from the bulkhead (B) (13) for installation of the crankshaft (not shown) and reinstalled in the identical preformed position. The bosses (26) are tapered, a moat (27) surrounds each boss (26), and the boss (26) may be provided with axial splines (not shown) and/or be oblong (not shown) in the axial direction. Voids (V1-V4) (not shown) may also be formed in the planar surfaces of the feet (T, 22, 522) (not shown) which abut the bulkhead (B) (13).
However, the boss (Protrusions) (26) here extends until 360° around bolt hole (21). Said boss (26) is provided with splines. The boss made around the bolt hole (21) damages the threads in the engine block (13) which creates problem while refitting the bearing caps (14). The boss (26) provided with spline shape is difficult to manufacturing in tool compared to other one.

A US patent publication no. US 2016/0131192 A1 discloses A bearing cap in which each foot includes a protrusion formed thereon that is generally linear having opposing sides in which each of these opposing sides support a plurality of crush ribs.
However, it has a Blunt button shaped projection. Blunt shape create excessive mechanical stress, it has been observed an appearance of cracks in the assembly area at the end of indentation cavity likely to cause breakage of the engine.

Disadvantages of the Prior Art:
The prior art described above suffers from one or more or all the disadvantages as listed below:
• Most of the prior arts fail to provide an improved bearing cap that eliminates the problem of repositioning.
• Most of the prior arts have selective assembly of the bearing cap i.e. the number of bearing cap used before machining; the same bearing cap is repositioned on the same place. An interchanged placement leads to misalignment in repositioning of the bearing cap.
• Most of the prior arts fail to eliminate the problem of misalignment which leads to noise, knocking and vibration in the engine; ultimately damaging the engine. This reduces the shelf life of the bearing cap and the engine.
• Some of the prior art requires precision machining operations on the main bearing cap to define the snap width and length to avoid an overstressed or loose main bearing cap in the structure, and are relatively expensive.
• Most of them have very poor accuracy of repositioning the bearing cap as the machining is not proper.
• Many of the prior art have exerts more pressure, which creates excess mechanical stress at the end of cavity. This leads to appearance of cracks in the assembly area at the end of indentation cavity that is likely to cause breakage of the engine. Therefore, the prior art have frequent possibilities of breakdowns. Thereby requires very high maintenance.
• Some prior art use precision dowels that incurs additional cost of purchasing precision dowels, their handling and installation, and the costly machining of precision bores in the bulkhead and main bearing caps.
Thus there is the need of the invention that obviates the problems of the conventional bearing caps.
Objects of the Present Invention:
Accordingly, the object of the present invention is to provide an improved bearing cap. In an aspect the present invention provides an improved bearing cap that enables the repositioning of the bearing cap accurate yet easy by eliminating the selective assembly of the bearing cap.

It is an object of the present invention to provide an improved bearing cap that eliminates the problem of misalignment if the position of the bearing cap is interchanged. In an aspect the present invention eliminates selective assembly of the bearing cap thereby aids in achieving proper alignment during interchangeability.

It is an object of the present invention to provide an improved bearing cap that eliminates the problem of misalignment, thereby providing noise free, knocking and vibration free engine. In another aspect the present invention increases the shelf life of the bearing cap and the engine.

It is also the object of the present invention to provide an improved bearing cap that has proper machining of the bearing cap thereby providing accurate repositioning of the bearing cap.

In another aspect the present invention provides an improved bearing cap that eliminates the requirement to apply excess pressure on the bearing cap and thereby does not create stress in the bearing cap and engine block. In an aspect the present invention avoids cracks in bearing cap and engine block and increases the shelf life of the bearing cap and engine block making it low maintenance.

It is the further object of the present invention to provide an improved bearing cap that eliminates the requirement of any special handling and installation, thereby making it a low-cost solution.

It is the object of the present invention to provide an improved bearing cap that eliminates the disadvantages of prior art.

Summary of Invention:

Accordingly, to achieve the foregoing objects the present invention provides an improved bearing cap. Said improved bearing cap facilitates and ensures the smooth working of crank shaft which is with reduced vibrations, noises and knocking. To ascertain the same, the present invention provides the round structured bore. Said round structured bore is due to the present improved bearing cap when mounted on the engine block during machining. It further facilitates the accurate repositioning of bearing cap after installation. Said improved bearing cap comprises engine block, Bearing Cap, Bore, Protrusions, Bolt, bolt holes, Faces, foot. It further eliminates the misalignment of the bearing cap over the shaft, in case where the position of the bearing cap is interchanged while assembly. Said invention may be installed at an engine where relocating of structural components to the supporting components is required.

Brief Description of Drawings:
Fig.1 : Shows the generalized function of the Bearing cap in an engine
Fig.2 : Shows the cross sectional view of one of the conventional bearing cap bolted to an engine
Fig.3 : Shows the cross sectional view of another conventional bearing cap bolted to an engine
Fig.4 : Shows the cross sectional view of another conventional bearing cap bolted to an engine
Fig.5 : Shows the cross sectional view of another conventional bearing cap bolted to an engine
Fig. 6 : Shows the cross sectional view of another conventional bearing cap bolted to an engine
Fig.7 : Shows the cross sectional view of main bearing cap bolted to an engine block of the present invention.
Fig.8 : Shows the detailed cross sectional view of main bearing cap bolted to an engine block of the present invention.
Fig.9 : Shows the bottom elevation view of main bearing cap of the present invention.
Fig.10 : Shows Left or right side elevation view of main bearing cap of the present invention.
Fig.11 : Shows the partial cross sectional view of engine block.

Description of Invention:
An embodiment of the present invention is to provide an improved bearing cap. The present invention provides the bearing cap that enables repositioning of the bearing cap over the shaft during bore machining accurately, and also makes it easy and user-friendly by eliminating selective assembly of the bearing cap. It further eliminates the misalignment of the bearing cap over the shaft, in case where the position of the bearing cap is interchanged after bore machining. It provides the bearing cap that substantially increases the shelf life of the engine block, requires less maintenance.

Meaning of reference numerals of component parts of Present invention:
P : Present Improved Bearing Cap
1 : Engine Block
2 : Bearing Cap
3 : Engine Block Faces
4 : Bearing Cap Faces
5 : Threaded Holes
6 : Bore
7 : Foot
8 : Bolts
9 : Bolt holes
10 : Protrusions
11 : Reliefs
12 : Indentation
13 : Engine block in Prior art
14 : Bearing Cap in Prior art
15 : Engine Block Faces in Prior art
16 : Bearing Cap Faces in Prior art
17 : Threaded holes in Prior art
18 : Supporting Bore in Prior art
19 : Bearing Cap Feet in Prior art
20 : Bolt in Prior art
21 : Bolt Hole in Prior art
22 : Engine Block slot face in Prior art
23 : Hollow dowels in Prior art
24 ; Counter holes of engine Block in Prior art
25 : Counter holes in Bearing cap foot in Prior art
26 : Bosses in Prior art
27 : Recesses in prior Art

Now, referring to Figure 7 to 11, the present invention (P) comprises:
• Engine Block (1),
• Bearing Cap (2),
• Engine Block Faces (3),
• Bearing Cap Faces (4),
• Threaded Holes (5),
• Bore (6),
• Foot (7),
• Bolt (8)
• Bolt holes (9),
• Protrusions (10),
• Reliefs (11),
• Indentations (12);

Said engine block (1) is the main structure and comprises of threaded holes (5). Said bearing cap (2) of the present invention is provided to support journal bearings through which crankshaft rotates and is connected to the engine block (1) by bolting through bolt holes (9) using said bolts (8). The bearing cap (2) and the engine block (1) attached together forms bore (6). Said bearing cap (2) is the semicircular structure bearing cap and is made by sintered powder metal thereby no addition cost is required . Further it has the extended foots (7) on each side. Said Bore (6) is provided to support the crank shaft in the engine. Said Bearing Cap Faces (4) are attached to the corresponding Engine Block Faces (3). Bearing Cap Faces (4) intersects with corresponding faces of engine block (1). The bearing cap faces (4) has perpendicular bolt holes through which bearing cap (2) is mounted by bolting. The bearing cap (2) has notch to receive an ear of journal bearings so as to prevent the journal bearings from rotating relative to bearing cap (2) and Engine block (1).

Said journal bearing supports the crank shaft and are generally made in two splits. The journal bearings consists of ear which gets guided/Aligned in the notch provided in bearing cap (2) thereby preventing the journal bearing from rotating relative to bearing cap (2) and engine block (1). Said journal bearing prevents friction between crank shaft, engine block (1) and bearing cap (2).

The bearing caps (2), has plurality of protrusions (10) preferably four on the Bearing Cap Faces (4) of the extended bearing cap foot (7), and are provided to create indentations (12) on corresponding engine block faces (3) during mounting of bearing cap (2) back on engine block (1). Said indentations (12) are produced by mounting bearing cap (2) on engine block (1) and are used to relocate the bearing cap (2) on said engine block (1) after installation of crank shaft. Further said protrusions (10) are symmetrically attached on either side of bolt holes (9). Said Protrusions (10) has the small filleted edge at the top that facilitates easy insertion into the engine block (1) to produce indentation (12). Also the taper allows easy removal of the bearing cap (2) from engine block (1) after bore (6) machining. Said protrusions (10) is structured such that it have length B in the axial direction which is less than width L of bearing cap (2). This prevents shifting of the bearing cap (2) in the axial direction. Said protrusions (10) comprises symmetric bolt holes (9) Said symmetric bolt holes (9) are also responsible for proper and accurate alignment of bearing cap (2) on engine block (1).

At the bases of each protrusions (10) reliefs (11) are provided. Said reliefs (11) does not creates excess stress on the corresponding Engine Block Faces (3) thereby reduces the possibility of developing cracks in said engine Block (1). Said reliefs also provides space to receive excessive material resulting from bulging of engine block material during mounting. Also it ensures the proper connection between said Engine Block Faces (3) and Bearing Cap Faces (4).

Working of the Invention:

The present invention may be installed at an engine where precisely relocating of structural components like bearing cap (2) to the supporting structure like engine block (1) is required after machining. The supporting structure such as engine block (1) is made up of ductile material like aluminium or aluminium alloy which allows indentation by protrusions (10) of another supporting structure like bearing cap (2) for relocating purpose.

In the present invention said bearing cap (2) is attached to the engine block (1) through bolt holes (9) for the process of bore machining. Said bearing cap (2) comprising of plurality of protrusions (10) at either side of the bolt holes (9). Said protrusion (10) produces the indentation (12) for the engine block (1) during the mounting of bearing cap (2). The bore (6), formed due to the mounting of the bearing cap (2) over the engine block (1); said bore (6) formed in the present invention (P) during the machining process is the perfect round structured bore (6). Upon the confirmation of the perfect round structured bore (6) the machining process is carried out. This facilitates the error free, Noise free and vibration less accurate mounting of the bearing cap (2) over the engine block (1). This is possible due to the specific alignment of the protrusions (10) and the rounded structure of the bore (6).

Post the accurate machining, said bearing cap (2) is removed from the engine block (1). The crankshaft is than placed on the machined bore (6) in the engine block (1). The bearing cap (2) is than placed to its original position and is mounted again through bolt holes (9). The protrusions (10) over the bearing cap (2) are aligned in to the indentation before machining process. When said bearing cap (2) is in its original position after installation said round structure occurs ensuring the smooth working of crank shaft which is with reduced vibrations, noises and nocking.
Working Example: (Test Results)

The present invention (P) was installed at various engines for conducting the trials. For instance a trial was conducted where said bearing cap (2) was mounted on engine block (1) by bolts (8) through bolt holes (9). The bolts were tighten with a torque of 160Nm. The hardness of said bearing cap (2) is greater than the engine block (1). Thus the protrusions (10) on the bearing cap (2) are not deformed and inserted with ease into the engine block (1). The protrusion (10) heights remains unchanged even after repeated assembly trials. The bearing cap (2) was able to regain its original position after repeated assembly trials. Thereby proving that the said rounded structure of the bore and said bearing cap (2) ensures the smooth working of crank shaft which is with reduced vibrations, noises and knocking also increases the shelf life of the engine requiring less maintenance.

Having described what is considered the best form presently contemplated for embodying the present invention, various alterations, modifications, and/or alternative applications of the invention for any system will be promptly apparent to those skilled in the art. Therefore, it is to be understood that the present invention is not limited to the practical aspects of the actual preferred embodiments hereby described and that any such modifications and variations must be considered as being within the spirit and the scope of the invention, as described in the above description.

Advantages of the invention:
The present invention has the following advantages:
It provides an improved bearing cap that makes the repositioning of the bearing cap easy by eliminating the selective assembly of the bearing cap.
It eliminates the problem of misalignment if the position of the bearing cap is interchanged.
It provides noise free, knocking and vibration free engine; thereby increasing the shelf life of the bearing cap and the engine.
Proper machining of the bearing provides accurate repositioning of the bearing cap.
The present invention does not require excess pressure thereby does not create stress in the cavity of the bearing cap, thereby avoids cracks in the bearing cap; increasing the shelf life of the bearing cap and making it low maintenance.
It eliminates the requirement of any special handling and installation, thereby making it a low-cost solution.

,CLAIMS:We Claim;
1. A bearing cap (2) with smooth working of crank shaft, reduced vibrations, noises and knocking; wherein said bearing cap (2) mounted on the engine block (1) comprises:
Engine Block Faces (3),
Bearing Cap Faces (4),
Threaded Holes (5),
A Bore (6),
A Foot (7),
Bolts (8)
Bolt holes (9),
Protrusions (10),
Reliefs (11),
Indentations (12);
said bearing cap (2) is attached to the engine block (1) by bolts (8) through bolt holes (9) and is configured to form a bore (6); said bearing cap (2) has the extended foots (7) on each side and a notch to receive journal bearings; it comprises plurality of protrusions (10) symmetrically attached on either side of bolt holes (9) through said bearing cap Faces (4) over the extended foots (7); said protrusions (10) are configured to create indentations (12) on said corresponding engine block faces (3);said reliefs (11) are configured at the base of the protrusions (10) to ensure the connection between said Engine Block Faces (3) and Bearing Cap Faces (4) and eliminating stress.

2. The bearing cap (2) as claimed in claim 1 wherein said bearing cap faces (4) has perpendicular bolt holes configured to mount the bearing cap (2) on the engine block (1).
3. The bearing cap (2) as claimed in claim 1, wherein said protrusions (10) are four and has filleted edge at the top configured to facilitate insertion of said bearing cap (2) into engine block (1).
4. The bearing cap (2) as claimed in claim 1 and claim 3, wherein said protrusions (10) has length B in the axial direction less than width L of said bearing cap (2).
5. The bearing cap (2) as claimed in claim 1,3 and 4, wherein said protrusions (10) comprises symmetric bolt holes (9) configured for accurate alignment of bearing cap (2) on engine block (1).
6. The bearing cap (2) as claimed in claim 1, wherein said bore (6) is round structured configured for smooth working of crank shaft, reduced vibrations, noises and nocking.
Dated this 11th February 2021

Gopi Trivedi (Ms)
IN/PA 993
Authorized Agent of Applicant
To,
The Controller of Patents.
The Patent Office
At Mumbai.