Portale di Ateneo - En.Unibs.it

I MECHANICS OF MACHINES
Introduction .
Size and units : technical system and SI . Calculation graph: tracking diagrams and related scales . General information about elements and kinematic pairs .

Bullets and complements of kinematics and dynamics of rigid motion .
Trajectory, velocity , acceleration , equations of motion and energy in the motions translatorio , axial rotation , rigid floor. Decomposition of the absolute motion in relative motion and drag: theorems of Coriolis and Rivals. Kinematics and dynamics of elementary mechanisms ( ordinary crank centered, quadrilateral , glyph ) .

Forces acting in machines.
Weight. Inertia forces . Forces of the elastic type . Forces of contact between solids. Sliding friction and its laws. Attrition. Rolling friction . Forces acting between the lubricated surfaces.

Dynamics of machines .
Absolute regime, periodic varied. Forces and torques , durable, passive. Work and power of the forces in machines. Connection to motor - transmission - load. Transmission ratio. Mechanical efficiency . Connecting mechanisms in series and in parallel. Reduction of forces and masses. Energy equation . Motorcycles in absolute regime , direct and retrograde . Unsteady : acceleration and braking . Motorcycles in periodic regime : periodic irregularities and calculation of the flywheel. Balancing of rotating rigid systems .

Simple theory of vibration.
Free vibration and forced vibration of single degree of freedom systems . Application to the foundations of the machines. Instruments for measuring vibration. Work on systems to N degrees of freedom. Bending and torsional critical speed .

II ORGANS OF MACHINES
II Bodies of machines ( description and operation) .
Transmission shafts and relative connection elements . Rigid couplings , rubber bands, joints, hydraulic . Notes on the grafts. Bearings and sliding bearings . Sprockets flat spur and helical gears with involute profile . Toothed wheels conical . Couple worm - worm wheel. Ordinary gearing . Planetary gear trains . Flexible Bodies : belts, ropes. Chocks and tape. Bodies of connection: screws, bolts .

III MACHINES
General .
Energy equation for a current of compressible and incompressible fluid in stationary state . Energy into a machine as chemical , calorific value . Energy transformation in a car, performance characteristics . Machine classification .

Piston pumps .
Description . Characteristic variables and relationships between them : prevalence, geometrical magnitudes , average speed , flow rate, average power returns. Suction height . Nod on air cases . Nod over other pumps : a capsulismo , gear .

Pumps fluid .
Prevalence theoretical and actual supplied by an impeller , effect of action and reaction , a function of the diffuser . Centrifugal pumps and axial description. Characteristic variables and relationships between them. Curves and influence them in choosing the pump. Speed ​​characteristic ns, and the most affordable forms of the pump variant ns . Suction head , cavitation , priming. Various control systems .

Fans .
Schematic description of the various types of fan and related uses. Sizes and characteristics .

Compressors .
Piston compressors . Description . Bullets on the cycle of the compressor. Characteristic variables and relationships between them. Multi-stage compressors . For flow control . Outline of compressor fluid .

Internal combustion engines .
Various types of motors and their reference cycles . 4-stroke engines and spark ignition ( Otto) and compression ignition (diesel) engines . Theoretical cycle and limit cycle . Examination of combustion. Intake, exhaust , and related work . Mechanical losses . Returns. Degree of filling ( volumetric efficiency ) . Characteristic quantities ( geometrical magnitudes , mean effective pressure , the actual average speed , time consumption and specific , etc. . ) And the relationship between them. Characteristic curves . Construction components , power systems and power . Fuels . Two-stroke engines .

Hydraulic drive .
Various types : Pelton , Francis , Kaplan, description, sizes and characteristics . Speed ​​characteristic and selection criteria and use . Nod on the regulation.