FIELD OF INVENTION
This invention- relates to a system for improved cooling of cylinder block of
engine in a motor vehicle. The invention is particularly directed to improved
cylinder block of engine. The present invention is even suitable for engine with
high compression ratio.
BACKGROUND/PRIOR ART
Cylinder block is provided in the engine area to accommodate stationary and
moving parts of the engine. The block comprises lubrication circuit to lubricate
moving parts in cylinder block and head. Further, it has cooling circuit to cool
the engine block and head.
Coolant jacket is located inside the cylinder block and integral thereto. Said
coolant jacket constitutes passage for coolant flow to cool down the cylinder
block. Thus the cylinder block has coolant jacket (J) encircling a plurality of
cylinder bores (1, 2,3) adapted for receiving coolant fluid flow as in fig. 1.
Further, a water pump is placed in proximity to first cylinder bore to supply
high pressure water towards both intake and exhaust side of water jacket.
Water pump involute exit is directed downward & has always tendency to
pump the coolant more towards bottom dead center as shown in fig. la. So the
coolant first travels to first cylinder of exhaust side which subsequently flows
to the last cylinder & finally to cylinder head. Due to pressure drop & coolant
flow toward bottom dead center, heat transfer in last cylinder is very poor,
which may lead to heating problem of engine. The cylinder block mainly
consists of top dead center and bottom dead center, wherein top dead center
consists of hotter zone than the bottom dead center.
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However, with the above provision more cooling of bottom dead center is
carried out whereas more cooling of top dead center is actually needed.
Thus with the aforesaid technical teaching adequate cooling of top dead center
can't be achieved.
In the state of art, there is availability of another cooling system according to
which low height water jacket is provided. Heat transfer of low height water
jacket is limited only in top dead center of cylinder because of absence of
coolant in bottom dead center. It may cause uneven heat transfer rate across
the height of the water jacket.
Thus in any engine, heat transfer in last cylinder is always inferior compared to
first to penultimate cylinder owing to uneven distribution of flow, coolant
pressure loss and stagnant flow.
Cooling improvement is necessarily becoming challenging area in recent trend
of higher compression ratio engine wherein cylinder temperature reaches very
high. Higher compression ration leads to higher risk of knocking which reduces
the low end torque as well as life of engine. Heat flux from an engine cylinder is
much higher at the top of the cylinder than at the bottom.
Hence, there is requirement to develop a cooling system, which can efficiently
attend to cooling requirements of both top and bottom dead center of cylinder
block.
Some publications may be discussed one by one hereinbelow though not
relevant to the disclosure of proposed application.
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The position of a passage separating member in the axial direction of the
cylinder bores is determined by causing a spacer to contact a bottom surface of
a water jacket. When the separating member is inserted in the water jacket, the
width of the separating member is reduced due to elastic deformation, so that
the separating member can be arranged in the water jacket.
With the above provision, coolant is prevented from moving between the upper
portion and the lower portion with respect to the separating member.
A device for control of flow of a cooling medium which is led through a channel
in an internal combustion engine, comprising at least one flow directing
element arranged in the channel for directing passing cooling medium in a
predetermined direction. Said flow directing elements are supported by a
supporting element intended to be mounted on said internal combustion
engine. Said flow directing elements are so arranged that they protrude from
the supporting element and into said channel.
The above focuses on design of gasket between cylinder block and head.
US20050217614A1: A cooling structure for uniformly cooling a bore wall of a
cylinder block using a cooling medium, the bore wall surrounding plural bore
regions, includes a water jacket portion which is provided so as to surround an
entire outer periphery of the bore wall, and which is supplied with the cooling
medium; and a water jacket spacer which is inserted in the water jacket
portion such that a space is provided between the bore wall and the water
jacket spacer. The cylinder block includes an inter-bore region which is
positioned in the vicinity of a boundary between the bore regions adjacent to
each other, and a region other than the inter-bore region; and a cross sectional
area of the space between the bore wall and the water jacket spacer in the
inter-bore region is smaller than a cross sectional area of the space between
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the bore wall and the water jacket spacer in the region other than the interbore
region.
A cylinder head is provided with liquid cooling system and a method for cooling
the cylinder head. The cylinder head includes a liquid jacket in which a coolant
flows along a main flow pathway from a coolant inlet to a coolant outlet. The
liquid jacket is interrupted between the coolant inlet and coolant outlet by
portals to cylinders of an internal combustion engine. A second portal is
arranged in a flow shadow of a first portal. The cylinder head in the liquid
jacket exhibits a flow guide wall with a constriction of the flow cross section,
and a baffle plate, which is arranged in the direction of the main flow pathway,
downstream from the flow guide wall.
Deflecting ribs are provided within a coolant jacket formed in a cylinder head in
such a manner as to protrude upwardly from bottom walls for directing the
flow of coolant toward exhaust-valve-port side port wall portions. The deflecting
ribs for deflecting part of the flow of coolant toward the exhaust-valve-port side
port wall portions are formed in such a manner as to extend from the intakevalve-
port side port wall portions, and gaps are left between the exhaust-valveport
side port wall portions and the deflecting ribs for allowing the coolant to
flow along the wall surfaces of the exhaust-valve-port side port wall portions.
OBJECTS OF THE INVENTION
The principal object of the present invention is to provide a system for
improved cooling of cylinder block of engine in a motor vehicle.
Another object of the present invention is to provide a system for improved
cooling of cylinder block of engine in a motor vehicle which overcomes
disadvantages associated with the prior art.
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Still another object of the present invention is to provide a system for improved
cooling of cylinder block of engine in a motor vehicle which satisfactorily cools
both top and bottom dead center of cylinder block.
Yet another object of the present invention is to provide a system for improved
cooling of cylinder block of engine in a motor vehicle which is efficient and
reliable.
SUMMERY OF THE INVENTION
According to this invention, there is provided a system for improved cooling of
cylinder block of engine in a motor vehicle comprising of novel water jacket in
the cylinder block of engine wherein said jacket is provided with coolant
deflector so as to direct the coolant towards top dead center of the block.
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 of exemplary embodiments of invention and wherein:
Fig. 1 shows: Conventional coolant jacket of cylinder block;
Fig. la shows: Coolant flow towards bottom dead center of cylinder block
according to prior art;
Fig. lb shows: Maximum cooling requirement area of cylinder block;
Fig. 2 shows: Coolant jacket of present invention
Fig. 3 shows: Deflector of coolant jacket in accordance with present
invention;
Fig. 4-5 shows: Coolant separator pocket in accordance with present
invention.
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DETAIL DESCRIPTION OF THE INVENTION WITH REFERENCE TO THE
ACCOMPANYING DRAWINGS
In an internal combustion engine, tendency of coolant flow should be from
cylinder block to cylinder head and then to the radiator through thermostat.
The desired coolant flow is the area in proximity to top dead center of the.bore
as shown in fig. lb& coolant should reach to cylinder head at the earliest.
The invention makes a disclosure regarding a system for improved cooling of
cylinder block of engine in a motor vehicle as illustrated in fig. 2 comprising of
novel water jacket (J) in cylinder block of engine (B) wherein said jacket is
having a coolant deflector (D) in intake and exhaust side of last cylinder (3) so
as to direct the coolant towards top dead center of the block together with
provision of coolant separator pocket (P) in intake side of the first cylinder (l)to
divide the coolant to flow in maximum heated area of the bore (bore outer wall)
as well as to direct the coolant towards cylinder head.
As already discussed, the cylinder block has multitude of cylinders. In this
particular exemplary embodiment of the present invention, the block has three
cylinders (1, 2, 3) as in fig. 2 without restricting scope of the invention to the
same. Thus, number of cylinders may vary according to the requirement.
Now, reference may be made to fig. 3. The jacket is having the provision of a
deflector (Di) in intake side and another deflector (D2) in exhaust side of last
cylinder (3).
Thus the jacket is having a deflector located between penultimate and last
cylinder (2 and 3) so as to deflect the coolant towards the last two cylinders
particularly for cooling the last cylinder (3) in top dead center. This provision
also fulfills the cooling requirement of bottom dead center of block. The
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deflector constitutes smooth angular cut in the water jacket for deflection of
coolant.
The coolant separator pocket (P) for which reference may. be made to fig. 4
receives coolant directly from radiator (R) of vehicle for cooling first bore (1)
outer wall prior to cooling of the entire cylinder block by means of high
pressure coolant from pump (F).The pocket is located preferably in the middle
portion of intake side of first cylinder (1) outer wall. Coolant separator pocket
provides arrangement for cooling of intake side of cylinder (1) by low pressure
water jacket as illustrated in fig 5.
The provision of pocket reduces load on the pump to cool down the entire block
unlike prior art. The pump is located near to first cylinder (1) of water jacket to
supply high pressure coolant towards both intake and exhaust side of water
jacket.
Advantageous Features
- Uniform heat transfer across each cylinder of block.
- Improved heat transfer in maximum heated zone i.e. top dead center
together with cooling of bottom dead center, which leads to better cooling
of whole engine.
- Even distribution of coolant flow to each engine cylinder.
- Avoids regions of stagnant flow.
- Efficient functioning.
It is to be noted that the present invention is susceptible to modifications,
adaptations and changes by those skilled in the art. Such variant embodiments
employing the concepts and features of this invention are intended to be within
the scope of the present invention, which is further set forth under the
following claims:-

We Claim:
1. A system for improved cooling of cylinder block of engine in a motor
vehicle comprising of novel water jacket in the cylinder block of engine
wherein said jacket is provided with coolant deflector so as to direct the
coolant towards top dead center of the block.
2. A system for improved cooling of cylinder, block of engine in a motor as
claimed in claim 1 wherein one coolant deflector is located in intake side
and another deflector is in exhaust side of the last cylinder.
3. A system for improved cooling of cylinder block of engine in a motor as
claimed in claim 1 or 2 wherein the deflector constitutes angular cut in
the water jacket for deflection of coolant.
4. A system for improved cooling of cylinder block of engine in a motor as
claimed in any of the preceding claims wherein the coolant deflector is
positioned between the penultimate and last cylinder.
5. A system for improved cooling of cylinder block of engine in a motor as
claimed in any of the preceding claims comprising a coolant separator
pocket in intake side of the first cylinder to divide the coolant to flow in
maximum heated area of the bore (bore outer wall) as well as to direct
the coolant towards cylinder head.
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6. A system for improved cooling of cylinder block of engine in a motor as
claimed in any of the preceding claims wherein said coolant separator
pocket receives coolant directly from radiator of vehicle for cooling first
bore outer wall prior to cooling of the entire cylinder block by means of
high pressure coolant from pump.
7. A system for improved cooling of cylinder block of engine in a motor as
claimed in any of the preceding claims wherein the pocket is located
preferably in the middle portion of first cylinder outer wall.
8. A system for improved cooling.of cylinder block of engine in a motor as
claimed in any of the preceding claims which fulfills the cooling
requirement of bottom dead center of block.
9. A system for improved cooling of cylinder block of engine in a motor as
claimed in any of the preceding claims is associated with the
advantageous features such as herein described.
J
10. A system for improved cooling of cylinder block of engine in a
motor substantially as herein described with reference to the
accompanying drawings.