Mechanical Auxiliaries: Energy Storage, Brakes, Clutches & More
Mechanical Auxiliaries for Optimal Operation
14 auxiliaries provide optimal operation of energy storage elements. These elements store energy and subsequently provide mechanical energy. Accumulators like the flywheel, typically a solid disk mounted on a shaft, ensure regular rotation, preventing irregular motion when the driving force is not constant. It also slows shaft rotation when it tends to accelerate and resists stopping.
Elastic Elements
Elastic elements deform under force and return to their original shape. They work in tension and compression (springs absorb energy as vibrations or force, then release it slowly, like in vehicle suspensions), flexion (crossbows use steel sheets that flex, straps absorb energy and release it slowly, used in toys), and torsion (springs absorb energy when twisted, like in Iberian bars).
Energy-Dissipating Elements
Energy-dissipating elements reduce or stop movement. Mechanical elements stop rotating parts, transforming kinetic energy into heat through friction. These are called brakes.
Types of Brakes
- Mechanical outdoor shoe: Friction occurs on the periphery of a disc joined to a shaft. The rubbing piece is coated with a high-friction material.
- Shoe drum: Friction occurs inside a cylinder. A shoe rubs against the drum to reduce its speed.
- Disk: A disc on the shaft has two pads applied on both sides.
Drive Mechanical Systems
Drive mechanical systems include:
- Mechanical systems
- Hydraulic systems: Use pipes to convey liquid, based on Pascal’s principle, with a plunger, pipe, and larger diameter plunger.
- Electric systems: An aluminum or copper disc rotates between electromagnet poles. Eddy currents slow the disc’s rotation, used in trucks and heavy vehicles.
Clutches
Clutches transmit movement between two aligned shafts. One shaft receives motor movement, and the other is coupled to the output shaft.
- Engaged: Transmission occurs between both shafts.
- Neutral: No transmission between shafts.
Types of Clutches
- Friction (disk): Two discs with high friction surfaces couple the shafts, matching their speeds.
- Teeth: Two front teeth cut on a disc.
- Hydraulic: A liquid transmits movement. Input shaft drives the liquid, forcing the second turbine. Perfect at high speeds, but at low speeds, the fluid force is unable to drag the wheel axle. It is an automatic clutch, used for trucks and buses.
Other Mechanical Elements
Supports sustain fixed or movable machine elements. Mobile elements need two or more support points on a fixed surface to move as required.
Bearings
Bearings are placed between the machine support and the shaft. They are used for three reasons:
- To reduce wear when a stock moves in relation to another.
- Axes or trees are generally made of the same material as the support.
- To prevent wear on the brackets, which would be expensive to replace.
Types of Bearings
- Friction bearings: Hollow cylinders where the shaft passes, made of softer material to protect the shaft. They come in axial (longitudinal load) and radial types.
- Ball bearings: Two concentric cylinders with balls or rollers between them, reducing friction. Made of steel, with greased tracks for smooth rolling.
Types of Ball Bearings
- Radial: Resists radial forces.
- Axial: Supports longitudinal forces.
- Mixed: Supports both radial and axial forces.
Lubrication
Lubrication involves applying a thin oil layer between moving surfaces to avoid contact. Synthetic oils are commonly used, classified by viscosity. The viscosity depends on the mechanism and conditions of use. There are 3 types of manual lubrication or bubbler-priced.