|The crankshaft as well as a structural point of view must also be studied for two fundamental aspects, the balancing of the forces generated by the movement of the reciprocating masses (piston, piston rings, piston pin and
small end of the connecting rod) and those rotating (big
end of the connecting rod, the crank pin), and also by the inertia that the crankshaft is able to offer.
In a single-cylinder engine, unless you introduce counter-rotating shafts, balancing can be only partial, and how to choose this partial balancing has always been the subject of discussion on what might be the best, in fact there isn't a better solution in absolute, but the optimum should be chosen according to the characteristics of the engine and of the vehicle for which the engine is employed.
Same goes for what concerns the crankshaft inertia, lighter, heavier, holes, no holes, are questions that recur over time,
at which isn't possible to give an answer because also for this aspect the best solution depends on the characteristics of the engine and its use.
In view of this, in practice, it makek the initial choices and then on the basis of tests and repeated attempts are made any changes, this process is long and laborious and often do not know if the solution found is really the best.
The software Crankshaft Balance Design may appraise in advance the technical effects that the choices
of balance and inertia give in terms of performance and reliability in relation to the characteristics of the engine and
of the vehicle on which it is applied, allowing you to quickly find the optimal solution.
|The software Crankshaft Balance Design
allows to analyze and to design
full circle crankshaft, both with
shoulders only in the big end rod zone, both with shoulders that cover
the entire cheek.
Moreover, the software allows you to analyze and study also
crankshafts with any single or double countershaft. This
therefore allows to work easily on all the main crankshafts.
With the software Crankshaft Balance Design you can both
analyze a crankshaft existing
assessing the status and possible modification and improvement, both
study and design a new crankshaft according to
the needs and characteristics of the engine and the chassis on which it is
applied the engine.
In the software Crankshaft Balance Design you can place
easily the crankshaft geometry
, could account for the presence of
shoulders, lightening holes, pads
balancing, etc. In addition to this, is sufficient just insert the
weights of slider crank elements
(connecting rod, piston, piston pin, etc.) and immediately
the software shows a full picture
of the characteristics of your crankshaft .
You will see the weight , the
percentage of balancing , the
presence of a possible asymmetry
and how many degrees moves the CG
of the crankshaft , and finally a comprehensive analysis of
inertia distribution , calculated in a manner
precise and without approximations pd2, etc.
Also if there are countershafts
single or double you can enter their
characteristics and take account of them in the
calculation of the balancing and of the overall symmetry of the
In addition to the calculations, the software draws
the geometry of the crankshaft that you entered,
allowing you to assess whether the data is correct and where there
is space for any modifications improvements.
| If you want to change an existing crankshaft or you want
study a new crankshaft, after the analysis phase that
allows you to have a complete picture of the situation, the software
Crankshaft Balance Design lets you go again
more in depth and to study the crankshaft which best
it adapts to the characteristics of the engine and to those of the
vehicle on which the engine is applied.
The software in the design area allows to make two
calculation balancing and inertia geometry
calculation of friction, frame forces, engine performance,
vehicle performance, etc.
|CALCULATION BALANCING and INERTIA GEOMETRY
| The first key aspect to
cure is the determination of the righteous
counterweights necessary to have a specific
balancing of the crankshaft. The software lets you
do it very quickly allowing even
choose with how much counterweights you want to create the
balancing desired , and if you want
positioning the counterweights to create more or
less inertia in the crankshaft.
The software tells you number, location and
size of the counterweights and also generates its
drawing to make easier the execution.
The other key aspect is that related to the inertia
of the crankshaft . The software calculates as you must
change the geometry to reduce or
increase the crankshaft inertia
, suggesting the realization
of hollows, holes , or the application of
pads of heavy material
As you can see from these examples, the software lets you
evaluate endless combinations of balance and inertia,
and among these you can study also balancing
asymmetric to move maximum loads on the bearings
in the engine cycle and thus have advantages in terms of
FRICTION - FRAME FORCES - ENGINE PERFORMANCE - VEHICLE PERFORMANCE
After making choices of balancing and inertia, and determining
thanks to the software how to implement them on the crankshaft, the software allows you to instantly see the effects
that they have on the performance and reliability of the engine and
the vehicle. In fact, as is known balancing influence the loads acting on the crankshaft and accordingly the magnitude of the friction, and the mechanical losses,
furthermore determines the vibrations and the loads that the frame has to bear. The
inertia on the other hand affects acceleration, engine braking, gear shifts, etc.,
so only through complete and accurate calculations of all these variables
you can really see if you've found or not the best solution for
For this reason the software Crankshaft Balance Design in addition to making the calculations for balancing and inertia desired, simulates the performance of the engine and the vehicle and then it becomes easy for the technician tuner make the best choice as it can immediately make a performance comparison viewing the mechanical losses of the engine, as the vehicle behaves during acceleration, what happens in gear shifts, what happens in release etc.
Moreover the software allows you to easily analyze the forces that are discharged on the frame, the irregularity of the
torque and of the phases, so it's possible to make fastly evaluation also as regards the reliability of the engine.
In addition to the identification of the optimal choices of crankshaft
balance and inertia the software can also be used to find the optimal
shift speed in relation to the characteristics of the power curve of the engine and
of the inertia overall.