FIELD OF THE INVENTION
Disclosed herein is a crank detaching mechanism for a multiple cylinder variable displacement engine. This invention relates specifically to crank detaching mechanism for Internal Combustion Engines. BACKGROUND OF THE INVENTION
It is known that under normal working conditions a 6 cylinder engine requires the power from 6 cylinders when the vehicle is moving in fully loaded condition. When the vehicle is without any load and only bearing the self-weight, it requires only the power generated in 3 cylinders for smooth driving especially in a smooth highway. By using pressure relief valves, the fuel supply into 3 cylinders may be cut off, so the cylinder deactivation process will take place. But the piston inside the cylinder is still in motion. It will cause the friction losses. This reduces the break power that the engine actually produced from the active cylinders. Therefore to reduce the frictional power, the crank itself has to be detached. In this method internal modifications are made in existing internal combustion engine.
The objects of the invention will become apparent after consideration of the following description of the invention and its preferred embodiments detailed hereinafter.
SUMMMARY OF THE INVENTION
It is the principal object of the present invention is to increase the total efficiency of an Internal Combustion(IC) engine having multiple cylinders when working with partial loads. It's known that by cutting off air and fuel supply of the part of total cylinder number the efficiency of the engine will increased to an extent. However the friction losses in the cylinders deactivated

by cutting of the fuel supply into the cylinders will reduce the efficiency of the 1C Engine.
It is the objective of the invention to split the crankshaft using a modified synchronizing unit by which crankshaft could be engaged and disengaged.
In order to separate the crankshaft, the crankshaft is cut at journal bearing position and it is made into two equal halves. In the cut journal bearing position of the crank shaft a modified synchronising unit is placed. Using this modified synchronizing unit the crankshaft is engaged and disengaged. Therefore when the cylinders are cut off, simultaneously the crankshaft is also disengaged. So the engine will work with half number of cylinders.
Another objective of this invention is to prevent breakage in firing order by introducing modifications in synchronizing Unit.
By using this mechanism the pumping loss, frictional loss, total fuel consumption will reduce significantly.
BRIEF DESCRIPTION OF THE DRAWINGS
Other objects and advantages of the present invention will become apparent from the following detailed description of the preferred embodiments thereof in connection with the accompanying drawings
Figure 1- shows the Modified Synchronizer hub: is rigidly connected by a spline to the rotating shaft (input or output shaft) .To maintain the firing order of the engine the engagement of the mechanism should be done at a single position. In normal case the synchronizer will engage at any position. So that we have to modify the tooth profile of synchronizer hub.
Figure-2- Modified Sliding sleeve: has a groove on the outer periphery for the gear shift fork. Includes internal splines that are in constant mesh with the modified synchro hub external splines, so it is only axially movable from a neutral position to an engaged position. Both parts and the main shaft work as a single unit hence they move at the same angular speed. The internal tooth in the

sleeve are modified by filling weld according to the modified tooth profile of other modified synchronizer parts.
Figure-3- Modified Synchronizer ring / Blocking ring / Balk ring / Friction ring: The external teeth interlock with the internal teeth of the sliding sleeve. It has a conical surface that is fitted with the conical surface of the clutch body ring. Its purpose is to produce the friction torque needed to synchronize the input and output shafts. The cone surfaces are provided with thread or groove patterns and axial grooves in1 order to either prevent or break the hydrodynamic oilfilm. To avoid relative motion between the ring and the hub the synchronizer ring is TIG welded with the strut detent.
Figure-4- Modified Clutch gear with cone: The external teeth with chamfer on both sides of the teeth interlock with the chamfer on the internal teeth of shift sleeve. In normal case the synchronizer will engage at any position. So that we have to modify the tooth profile of synchronizer hub.
Figure-5 &6- Modified Strut detent / Centring mechanism / Strut key: spring loaded ball or roller fixed in a cage. It is arranged on the circumference of the synchronizer body, positioned between the groove in modified synchro hub and the inner groove in shift sleeve. Therefore can integrally rotate with the modified synchro hub and is axially movable with the shift sleeve. This component is used for pre-synchronization; it means that generates the load on synchro ring to perform the synchronization process. In addition, maintains the sliding sleeve in a central position on the hub between both gear wheels and below a limit axial force. Often, the synchronizers are composed by three of these elements arranged at 120°. In the case of large synchronizers, there are four elements arranged at 90°.To avoid relative motion between the ring and the hub the synchronizer ring is TIG welded with the strut detent.

Figure No.7& 8 -Shows the isometric view of the crank detaching mechanism. The Various parts of crank detaching mechanism are marked in the Figure No. 7and 8 as follows:
Part- A- Modified Synchronizer Sleeve
Part -B- Modified Synchronizer Hub
Part-C- Modified Synchronizer Cone
Part- D- Modified Gear Wheel
Part- E- Modified Strut Assembly
Part-F- Modified Crank Shaft
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
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.
It is to be understood that the singular forms "a," "an," and "the" include plural referents unless the context clearly dictates otherwise. Thus, for example, reference to "a component surface" includes reference to one or more of such surfaces.
Figs. 7 and 8 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 communications system. 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. Terms first, second, and the like are used to differentiate between objects having the same terminology and are in no way intended to represent a chronological order, unless where explicitly stated otherwise. A set is defined as a non-empty set including at least one element.
An aspect of the present invention is to address at least the above-mentioned problems and/or disadvantages and to provide at least the advantages described below.
Figure lto 8 shows the various parts of the crank detaching mechanism.
The Figure no-8 shows in general the structure of the new Crank detaching mechanism.

For the purpose of explaining the invention completely 6 cylinder diesel IC Engine is used. Cutting the crankshaft into two equal parts at the central journal bearing portion, modification of synchronizing unit, placing the modified synchronizing unit in the cut portion of crank shaft, providing a lever mechanism for engaging and dis engaging the crankshaft using modified synchronizing unit. All the fabrication details are explained in the following section in detail
Cutting of Crankshaft
The crankshaft of the six cylinder engine is needed to cut into two equal half in order to place the modified synchronizing unit. For that the crankshaft is cut at the middle of the main joumaJ bearing portion. The cutting of crankshaft is done by using power saw. On the production side it should be molded as half shafts.
Providing Pilot Bushing
The pilot bushing is seldom thought of as a part of the clutch system but it is one of the most vital parts of the system. The pilot bushing is only functional when the clutch is disengaged but it is a factor in input gear alignment at all times.
The job of the pilot bushing is to support the end of the transmission input (main drive) gear in the crankshaft. This pilot bushing should be a light drive fit into the crank bore. Care should be taken when installing any pilot bushing as they are soft and easily damaged by crude installation techniques. We have used this method to save engine disassembly many times. The male portion of the pilot bushing is provided on one of the cut portion of the crankshaft in which the flywheel is present. And the female portion is bored on the next half of the cut crankshaft. Pilot bushing is done on the crankshaft using heavy duty lathe.

Providing Splines on Cut Portions of Crankshaft
The modified synchronizing hub is placing in one of the cut portion of the crankshaft in which the timing gear assembly is present. In order to fix the hubj external splines are made on the cut portion of the crankshaft according to the internal splines on the hub.
The gear wheel is fixed on cut portion of the crankshaft in which the flywheel is present. In order to fix the internally splined gear wheel the crankshaft is externally splined.
Modification on gear wheel
Gear wheel is internally splined in order to fix it on the cut portion of the crankshaft and also to avoid the slip during running condition. In order to assemble the modified synchronizing unit in the available space the thickness of gear wheel is reduced by 'facing operation' in lathe.
Welding of synchronizer ring with the strut detent
To avoid relative motion between the ring and the modified hub the synchronizer ring is TIG welded with the strut detent. Since it requires more strength we preferred TIG welding. Copper is used as the electrode.
Modification of tooth profile
To maintain the firing order of the engine, the engagement of the mechanism should be done at a single position. In normal case the synchronizer will engage at any position. So that we have to modify the tooth profile of synchronizer hub, synchronizer ring, sleeve and gear wheel.
The tooth are removed progressively as 1, 2 and 3 at an angle 120° in hub, ring and gear wheel. The internal tooth in the sleeve are modified by filling weld according to the modified tooth profile of other synchronizer parts.
FABRICATION OF FORK LEVER ASSEMBLY
The fork is welded with the lever and it is extended outward through the
holes made on the casing to operate it from outside. /

WORKING
Normally a six cylinder engine provides power from all the six cylinders to Vehicle both in foil load condition and part load condition. Here we are doing a modification in the six cylinder engine to make it run at 3 cylinder condition as well as 6 cylinder condition. Hence we can use the engine as 6 cylinder engine during the full load condition and also the same engine can be use as 3 cylinder engine during part load condition. We are achieving this by using a modified synchronizing unit.
We placed the modified synchronizing unit in the central journal bearing position of the crankshaft. The modified synchronizing unit is operated by a lever externally. The lever has two functions one is to engage and dis engage the crankshaft and the other is to actuate the pressure relief valve. The engagement and dis engagement of the crankshaft can be done by moving the lever forward and backward respectively. When the modified synchronizing unit is in engaged condition all the six cylinders will work together. While the modified synchronizing unit in dis-engaged condition only the 3 cylinders will work at that time. The normal firing order of the 6 cylinder engine is 1-5-3-6-2-4, after the dis-engagement of the modified synchronizer unit the firing order will be 1-3-2, this firing order is similar to the firing order for a normal 3 cylinder engine.
While dis-engaging the crankshaft using the modified synchronizing unit the fuel supply to the 3 inactive cylinders will be cut off by using pressure relief valve which actuates by the lever. The pressure relief valve is placed in the fuel line which is in between the fuel pump and the fuel injector. The pressure relief valve has single inlet and dual outlet valve. One outlet is connected to the fuel injector and the other is connected to the fuel tank. Hence while disengaging the crankshaft the pressure relief valve gets actuated and the fuel from the pump to the inlet of the pressure relief valve gets redirected to the fuel tank, then the fuel

supply to the 3 inactive cylinders gets cut off. Thus the cylinder deactivation with crank detaching mechanism can be successfully accomplished.
The engaging and dis-engaging the crankshaft using modified Synchronizing unit will not adversely affect the normal engine working by the aid supporting mechanisms like providing timing gears using separate circuits, providing bearing in the journal portion and providing pilot bush in the crank shaft. By applying this mechanism we can improve the fuel efficiency up to 37% in vehicles. The frictionai power lose happening in engines and the total fuel consumption in engines also can be reduce considerably by implementing this.
Compared to normal displacement engine the engine with both fuel cut off mechanism and crank detaching mechanism can have much better efficiency in every condition. The other advantages available as a result of implementing this' mechanism are, the Pumping losses are reduced, also breathing problems inside the engine can be reduced, and as a result the engine life can be improved.
Thus we can reduce the frictionai power losses during 3 cylinder condition. This will improve the engines fuel efficiency, enhances power output of the engine during 3 cylinder condition, and it will reduce engines breathing problem. Moreover it will help to reduce the air pollution up to some extent.
While the preferred embodiments of the invention have been described above, it will be recognized and understood that various modifications may be made therein and the appended claims are intended to cover all such modifications which may fall within the spirit and scope of the invention.

I Claim
1. A Crank Detaching Mechanism for Multiple Cylinder Variable
Displacement Engine comprising of
a. A Modified Synchronizer hub having a modified tooth profile to
engage in a single position
a. The Modified Synchronizer hub rigidly connected by a spline to
the input or output rotating shaft.
a. A Modified sliding sleeve in which the internal tooth in the
sleeve are modified according to the modified tooth profile of the
hub and the gear wheel
a. A Modified Synchronizer ring / Blocking ring / Balk ring /
Friction ring comprising of the external teeth interlock with the
internal teeth of the sliding sleeve having a conical surface that is
fitted with the conical surface of the clutch body ring.
a. A Modified Clutch gear with cone and, the external teeth with
chamfer on both sides of the teeth interlocked with the chamfer on
the internal teeth of shift sleeve.
2. The Modified Synchronizer maintains the firing order of the engine by engaging at a desired position of the crank shaft.
3. The Modified Synchroniser hub enables engagement and disengagement of crank while engine is running.
4. The Modified Synchronizer hub reduces the vibration, shock and noise while engaging and disengaging the crank.
5. The Modified Sliding sleeve is only axially movable from a neutral position to an engaged position as the main shaft work as a single unit hence they move at the same angular speed.

6. The Modified Synchronizer ring / Blocking ring / Balk ring / Friction ring produce the friction torque needed to synchronize the input and output shafts.
7. Modified Strut detent / Centring mechanism / Strut key: spring loaded ball or roller integrally rotates with the modified synchro hub and is axially movable with the shift sleeve as it generates the load on synchro ring to perform the synchronization process.
8. By placing the modified synchronizing unit in the central or desired position of the crankshaft the desired number of cylinders could be engaged and disengaged.
9. The Crank Detaching Mechanism for Multiple Cylinder Variable Displacement Engine
a. improves fuel efficiency
b. reduces frictional power losses
c. improves engine breathing
d. consequentially reduces pollution