FIELD OF INVENTION The present invention relates to an apparatus for chain load measurement. More specifically, the present invention is related an apparatus to measure load or force of chain in running condition of engine or dynamo.

BACKGROUND OF INVENTION In general, chain drives are used in motorcycle or other saddle type vehicles for the transmission of rotation. The chain employs a variable force/load in moving condition with respect to the varying engine R.P.M. (number of times the crank shaft rotates about its axis). Different approaches for measuring the force exerted on a chain are described in prior art. In which there are some high end apparatus that incorporates transduces or sensors to measure load and some are low end apparatus such as manual scales those are either not calibrated arid/or not feasible for measuring load in running condition of engine or dynamo. Further, due to unavailability of any portable and cost-effective apparatus, the load of chain remains unknown/ or calibrated for applications such as tensioner designing etc. Hence, in view of aforementioned, it is required to devise an apparatus for chain load measurement that can overcome one or more limitations of the prior art. ^;

SUMMARY OF INVENTION

Embodiment of invention discloses an apparatus to measure load or force of chain in running condition of an engine or dynamo. The apparatus for chain load measurement is designed to assemble in the proximity of chain to measure load pertaining the chain on the running condition of engine.

An apparatus for chain load measurement is comprised of a housing, a plunger accommodated inside and arranged to protrude outside from an opening of the housing and spring arranged to bias the plunger to slide-ably protrude outside the housing. The apparatus for chain load measurement further comprised a load measuring shaft arranged on another opening of the housing is coupled to the plunger in a way that the load measuring shaft drive inside the housing 102 as the plunger protrudes outside the housing.

In an aspect of the present invention, a metric scale arranged along the load measuring shaft to measure the displacement of load measuring shaft, wherein the load exerted on the tensioner is calculated by recoding the length of the load measuring shaft on the metric scale. The apparatus for chain load measurement includes a load measuring shaft arranged to slide inside housing and biased by spring force. The load measuring shaft comprises holes to insert a pin or other locking means at one or more of predefined and/or arbitrary positions.

It is an object of the present invention to measure the chain load on vehicle or dynamo.

It is another object of the present invention to measure the chain load w.r.t. engine R. P. M.

It is a further object present invention to measure the chain displacement w.r.t. engine R. P. M. It is yet an object of the present invention to measure the chain load for creating a chain force specification that is required for tensioner design.

Some or major aforementioned advantages of the present invention are accrued by fixing a metric scale parallel to the load measuring shaft and/or integrating metric scale parallel with the load measuring shaft 108 for easy visualization of displacement of load measuring shaft. Further advantages are for chain load measurement in tensioner design. The user can measure the load in one engine run (need not to stop vehicle engine at each instance for observing displacement of load measuring shaft). BRIEF DESCRIPTION OF DRAWINGS

The detailed description is described with reference to the accompanying figures. In the figures, the same numbers are used throughout the drawings to reference identical features and/or components.

FIG. 1A represents the section view of an apparatus for chain load measurement in accordance with an aspect (wounded condition) of an embodiment (10) of the present invention;

FIG. IB represents the section view of the apparatus for chain load measurement in accordance with another aspect (released condition) of an embodiment (10) of the present invention; FIG. 1C represents the side view of the apparatus for chain load measurement in accordance with an embodiment of the present invention;

FIG. ID represents the front view of the apparatus for chain load measurement in accordance with an embodiment of the present invention;

FIG. 2 represents the apparatus for chain load measurement in accordance with another embodiment (20) of the present invention, and

FIG. 3 is a graphical representation of loads determined at various R.P.M. with a method of chain load measurement in accordance with a further embodiment of the present invention. DETAILED DESCRIPTION OF EMBODIMENTS

The instant disclosure is provided to further explain the best modes of performing one or more embodiments of the present invention. The disclosure is further at the plurality of pre-defined and/or arbitrary positions, securely. The other locking means can be a hook, a key type mean, a clip or lever etc. The design of hole can be adjusted in accordance with the design of pin (or other locking mean) and vice versa. In an embodiment of present invention, the at least one hole is designed at a predefined position to lock the load measuring shaft using the pin or locking means for holding purpose or for maintaining the wounding the height necessary for the assembly of apparatus for chain load measurement on or in proximity of the engine. Referring to a further embodiment (20) of the invention as shown in FIG. 2, the apparatus for chain load measurement 200 includes the metric scale integrated with the load measuring shaft 108.

Referring to FIG. 3, a method of operating the apparatus 100 for chain load measurement is disclosed in the present invention. Initially, the apparatus 100 for chain load measurement is installed near the chain drive inside the engine. In some embodiments it can be partially protruded inside the engine case and installed in the proximity of chain drive. Further, the pin (stopper pin or circlip) is removed to release the plunger 104. On release of the plunger ; 104, the load measuring shaft 108 sets at an initially value. The user can take the initial readings by looking the metric scale 1 10 provided with the apparatus 100 for chain load measurement. After recording the initial reading, the engine can be started/turned on(on stand/in standing condition of vehicle) from a minimum R. P. M. to be reached at different levels such as 1200 R.P.M., 1500 R.P.M., 1800 R.P.M. and 2000 R.P.M. etc.

The user can take the readings different levels such as 1200 R.P.M., 1500 R.P.M., 1800 R.P.M. and 2000 R.P.M. etc. by looking at the metric scale 1 10. Further for calculating the chain load the user can plot the chain force versus engine R.P.M as depicted in FIG. 3. In FIG. 3, data is collected from metric scale. The data is plotted against the different R.P.M.s and chain load is calculated using mathematical relationship ; displacement and constant spring rate at different R.P.M.S.

Some or major aforementioned advantages of the present invention are accrued by fixing a metric scale 1 10 parallel to the load measuring shaft 108 and/or integrating metric scale 110 parallel with the load measuring shaft 108 for easy visualization of displacement of load measuring shaft.

The above mentioned embodiments (10), (20) and/or others can be used either separately or can be combined according to the objectives/applications. One main application is find this apparatus 100 for chain load measurement in tensioner design. The user can measure the load in one engine run by giving acceleration (need not to stop vehicle engine at each instance for observing displacement of load measuring shaft).