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FIELD OF INVENTION
This invention relates to internal by-pass circuit for air bleeding from water jacket of a cylinder head in a gasoline engine to improve the cooling performance of cylinder head.
PRIOR ART
Reference may be made to fig. 1-5 indicating conventional designs.
Fig. 1 shows: the exploded view of prior art, wherein cylinder head (lA) is mounted on the cylinder block (2) with the help of 8 nos. of cylinder head bolt (4). In between the cylinder head (lA) 85 cylinder block (2) cylinder head gasket (3A) is placed with the help of two dowel pins (5) for sealing of combustion chamber, water and oil galleries. Water enters into cylinder block (2) water jacket from inlet hole (12). Water inlet cap (7A) along with water cap union (7X) 85 cap gasket (6) is mounted on the cylinder block (2) with the help of two screws (8). One end of by-pass hose (9) is mounted on the cylinder head union (11) and the other end on the water inlet cap (7A) with the help of clamp (10).
Fig. 2 shows: the exploded view of water pump (15) assembly with the engine. Water pump (15) is mounted on the cylinder block (2) with the help of one gasket water pump (14) and 5 nos. of mounting bolts (16). Water pump pulley (17) is mounted on the water pump (15) with the help of three mounting bolt (18). Water pump (15) gets drive from the engine crankshaft with the help of poly-V belt. Fig. 2 &, Fig 3 shows the flow of water in system. Water from radiator enters from hole (19) of water inlet cap (7A) and then enters into the cylinder block (2) water jacket (22). Water pump (15) sucks the water from water jacket (22) from hole (20) [shows in fig. 2] and then pressurized water from water pump (15) is pushed into the water jacket (22) from entry hole (21)

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[shown in fig. 2]. This pressurized water flows into the water jacket (22) and rises into the cylinder head (lA) water jacket (23) from the holes provided into the cylinder head gasket (3). This pressurized water does the cooling of cylinder head and then flows back to radiator from hole (13). Due to the construction of the water jacket (23) air present in the water jacket tries to accumulate in the region (24) which reduces the cooling efficiency of cylinder head (lA) in that region. In cylinder head water jacket (23) water circulation is improved by providing a by-pass circuit in which a by-pass hose (9) communicates with water inlet cap (7A). Therefore water pump suction head is attached with water jacket (23) with the help of by-pass hose (9) and water flows from it. This flow of water removes the air trapped in the region (24) and improves the cooling efficiency.
Fig. 4 shows the cut section of Cylinder head (lA) as per fig. 2. Water jacket (23) is shown in the cut section and region (24) is shown where air entrapped. By-pass hose (9) sucks the air 8B water from the region (24) and improves the water circulation in that region. Increased water velocity improves the convective heat transfer from that region and as a result cooling performance improves.
For removing the air from region (24), external by-pass circuit is used in this design. By-pass hose (9), two clamps (10) and union (11) in the cylinder head (lA) and inlet union (7X) in water inlet cap (7A) are provided. Major disadvantages involved with this design are as follows:-
1. Higher cost due to more number of parts.
2. More space requirement.
3. Higher assembly time.
4. Less reliability due to more number of joints.
There are extra number of parts included in this assembly like by-pass hose (9), two clamps to join hose (9) with cylinder head union (11) & water inlet cap

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union. The reliability of the assembly reduces because of four number of joints. As the structure is assembled outside the engine therefore, it takes more space and special care has to be taken while assembling the structure.
Moreover, water pump (15) needs more power to pump water because of complex shape of hose (9). More number of parts increase cost and assembling time also.
STATEMENT OF INVENTION
According to this invention, there is provided Internal by-pass circuit for air bleeding to improve the cooling performance of cylinder head comprising of a cylinder head mounted on a cylinder block wherein water from radiator enters into the cylinder block water jacket, pressurized water from which does the cooling of said cylinder head in which the water jacket is accumulated with air, which reduces cooling efficiency of cylinder head, wherein for removal of air from said water jacket
The cylinder head water jacket is provided with atleast one boss, which is drilled/atleast one press fitted union to create a by-pass passage internally from water jacket as shown in the accompanying figures.
BRIEF DESCRIPTION OF THE ACCOMPANYING DRAWINGS
Further objects and advantages of this invention will be more apparent from the ensuing description when read in conjunction with the accompanying drawings and wherein:
Fig. 1-4 shows: prior art.
Fig. 5 shows: Exploded view of present invention
Fig. 6 shows: water flow of the present invention.
Fig. 7 shows: sectional view according to fig. 6.

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Fig. 8 shows: water flow in water jacket and head water jacket.
Fig. 9 shows: sectional view according to fig. 6.
Fig. 10 shows: water flow in block water jacket and head water jacket.
Fig. 11-13 shows: cylinder head bottom face, cylinder head bottom face with cylinder head gasket and section c-c (showing water jacket) respectively of the prior art.
Fig. 14-16 and 17-19 shows: cylinder head bottom face, cylinder head bottom face with cylinder head gasket and section c-c (showing water jacket) respectively of present invention.
DETAIL DESCRIPTION OF THE INVENTION WITH REFERENCE TO THE ACCOMPANYING DRAWINGS:
This invention is directed to an internal by-pass circuit which is used to bleed the air from the water jacket of a cylinder head to improve the cooling performance of the cylinder head.
In water jacket areas of cylinder head water circulates for cylinder head cooling but due to the construction of the water jacket, during the circulation of coolant all the air present in the cylinder head water jacket area accumulates at a specific region and creates on air lock. This air lock deteriorates the cooling of cylinder head in this region. For effective cooling of cylinder head this air required to be bled-off from the water jacket area.
For bleeding the air from water jacket area following two provisions are made:
1. Adding one boss in cylinder head water jacket and drilling it to create a by-pass passage internally from water jacket.
2. Adding one press fitted union in cylinder head water jacket to create a by-pass passage internally from water jacket.

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Fig. 5 shows: the exploded view of present invention, Cylinder head (IB) is mounted on the cylinder block (2) with the help of 8 nos. of cylinder head bolt (4). In between the cylinder head (IB) 85 cylinder block (2) cylinder head gasket (3B) is placed with the help of two dowel pins (5) for sealing of combustion chamber, water and oil galleries. Water enters into cylinder block (2) water jacket from inlet hole (12). Water inlet cap (7B) 85 cap gasket (6) is mounted on the cylinder block (2) with the help of two screws (8). Water pump (15) is mounted on the cylinder block (2) with the help of one gasket water pump (14) and 5 nos. of mounting bolts (16). Water pump pulley (17) is mounted on the water pump (15) with the help of three mounting bolt (18). Water pump (15) gets drive from the engine crankshaft with the help of poly-V-belt.
Fig. 6 show the water flow of the present invention, in which water from radiator enters from hole (19) of water inlet cap (7B) and then enters into the cylinder block (2) water jacket (22). Water pump (15) [shown in fig. 5] sucks the water from water jackets (22) from hole (20) [shown in fig. 6] and then pressurized water from water pump (15) is pushed into the water jacket (22) from entry hole (21) [shown in fig. 6]. This pressurized water flow into the water jacket (22) and then rises into the cylinder head (IB) water jacket (23) from the holes provide into the cylinder head gasket (3B). This pressurized water does the cooling of cylinder head and then flows back to radiator from hole (13). Due to this construction of the water jacket (23) air present in the water jacket tries to accumulate in the region (24) which reduces the cooling efficiency of cylinder head (IB) in that region.
The present invention is provided with two provisions to remove the air from region (24) as follows:-
Adding one boss in cylinder head water jacket followed by drilling it to create a by-pass passage internally from water jacket in region (24).
Adding one press fitted union in cylinder head water jacket to create a by-pass passage internally from water jacket in region (24).

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Further reference may be made to fig. 7 indicating the cut section as per fig. 6. In this cut section, water jacket (23) and region (24) is shown where air gets entrapped. To bleed this air one boss (25) is provided in the cylinder head (IB) casting and one by-pass hole (26) is drilled through this boss (25). This by-pass hole (26) communicates with the water jacket (22) suction side.
Fig. 8 shows the water flow in block water jacket (22) 86 head water jacket (23). Water 85 air from region (24) is sucked by the water pump (15) through machined hole (26). This machined hole (26) creates an internal by-pass passage and improves the flow velocity in region (24) and also removes the air entrapped in this region (24). Due to this cooling performance in cylinder head improves.
Further, reference may be made to fig. 9 indicating the cut section as per fig. 6. In this cut section, water jacket (23) and region (24) shown where air gets entrapped. To bleed this air one union (27) is press fitted in the cylinder head (IB) to make a by-pass passage. This union (27) communicates with the block water jacket (22) suction side.
Fig. 10 shows the water flow in block water jacket (22) & head water jacket (23). Water 8B air from region (24) is sucked by the water pump (15) through union (27). This union (27) creates an internal by-pass passage and improves.
The flow velocity in region (24) and also removes the air entrapped in this region (24) and also removes the air entrapped in this region (24). Due to this cooling, performance in cylinder head improves.
Comparison Between Prior Art and Present Invention
Fig. 11 shows the bottom face of cylinder head (lA) in which hole (28) is used as a water return hole from cylinder head water jacket (23) to block water jacket (22).

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Fig. 12 shows the hole (29) in cylinder head gasket (3A) for water return.
Fig. 13 shows the cut section C-C as per fig. 11 in which region (24) of water jacket (23) is indicated. Water is being sucked from hole (30) of cylinder head through union (11) to water pump for removing the air entrapped in region (24).
Fig. 14 shows the bottom face of cylinder head (IB) in which hole (31) is used as a water return hole from cylinder head water jacket (23) to block water jacket (22).
Fig. 15 shows the two holes (32) in cylinder head gasket (3B) for water return.
Fig. 16 shows the cut section C-C as per fig. 14 in which region (24) of water jacket (23) is shown. Water is being sucked from hole (26) of cylinder head to water pump for removing the air entrapped in region (24).
Fig. 17 shows the bottom face of cylinder head (IB) in which hole (33) is shown which is used as a water return hole from cylinder head water jacket (23) to block water jacket (22).
Fig. 18 shows the two holes (32) in cylinder head gasket (3B) for water return.
Fig. 19 shows the cut section C-C as per fig. 17 in which region (24) of water jacket (23) is shown. Water is being sucked from union (27) of cylinder head to water pump for removing the air entrapped in region (24).
Advantageous features
1. Less number of parts due to deletion of union (11), hose (9), two clamps (10) 8B inlet cap union (7X).
2. Cost effective and light weight due to deletion of parts used in prior design.
3. Improved reliability due to elimination of a plurality of joints in coolant circuit.

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4. Reduction in assembly time as compared to prior design due to less number of parts.
5. Less space occupied by the new design i.e. compact as compared to prior design.
6. Less power consumption by water pump due to simplified coolant passage which results in less fuel consumption.
7. Less capital investment in machining line of cylinder head due to simple machining of cylinder head.
8. Reduction in cylinder head machining time due to simplified machining.
It is to be understood that the above-described embodiments are illustrative of only a few of the many possible specific embodiments, which can represent applications of the principles of the invention. However, numerous and varied other arrangements can be readily devised in accordance with these principles by those skilled in the art without departing from the spirit and scope of the invention.

WE CLAIM;
1. Internal by-pass circuit for air bleeding to improve the cooling
performance of cylinder head comprising of a cylinder head mounted on
a cylinder block wherein water from radiator enters into the cylinder
block water jacket, pressurized water from which does the cooling of said
cylinder head in which the water jacket is accumulated with air, which
reduces cooling efficiency of cylinder head, wherein for removal of air
from said water jacket
the cylinder head water jacket is provided with atleast one boss, which is drilled/atleast one press fitted union to create a by-pass passage internally from water jacket as shown in the accompanying figures.
2. Internal by-pass circuit for air bleeding as claimed in claim 1, wherein the by-pass hole communicates with water jacket suction side.
3. Internal by-pass circuit for air bleeding as claimed in claim 1 or 2, wherein the invention is associated with the advantageous features such as herein described.
4. Internal by-pass circuit for air bleeding to improve the cooling performance of cylinder head substantially as herein described with reference to the accompanying drawings.