Automotive Lubrication, Injection Systems & Engine Performance
Objectives of Lubrication
Primary Objectives
- Reduce friction – minimizes resistance between moving parts.
- Minimize wear – protects surfaces from damage and extends component life.
- Dissipate heat – carries away heat generated due to friction.
- Form a protective film – prevents direct metal-to-metal contact.
- Enhance efficiency – reduces energy losses during operation.
Secondary Objectives
- Prevent corrosion – acts as a barrier against moisture and chemicals.
- Seal contaminants out – helps in sealing
Mechanical Energy Accumulators and Dissipators
Mechanical Energy Accumulators
This is a device that can store or accumulate a certain amount of mechanical energy and return it when needed.
Types:
- Flywheel: Mechanical energy accumulated in the form of kinetic energy of rotation.
- Elastic Elements: Accumulate energy in the form of elastic potential energy.
Flywheel Details:
Consists of a wheel or disc, made of cast iron or steel, set on the motor shaft that rotates jointly with it.
Elastic Elements Details:
- Springs: These elastic elements are deformed
Mechanical Components and Power Transmission Systems
Fundamental Mechanical Definitions
Basic Rotating Components
Shaft
A shaft is a single piece, generally cylindrical, capable of transmitting circular motion and torque.
Axle
An axle is simply a piece, usually cylindrical, around which other parts of a mechanical assembly revolve.
Shaft Couplings
Couplings are devices used to connect two shafts together at their ends for the purpose of transmitting power.
Rigid Coupling
Rigid couplings join shafts using rigid metal pieces that are fastened by clamps or non-
Disk Scheduling Algorithms: FIFO, SSF, SCAN, C-SCAN
Disk Scheduling Algorithms
A. B. C. D. E. F. G. H.
seek: 0. 0. 0. 0. 8. 8. 8. 14.
cyl req 12. 4. 10 2. 20. 3. 17. 4
If these requests are served in FIFO order, then the following sequence of seeks ensues:
At time 0, requests A, B, C, and D arrive. To serve A, we seek 4 cylinders outward from 8 to 12. At time 4, we seek 8 cylinders inward to reach cylinder 4 and serve B (meanwhile E, F, G arrive). At time 12, we seek 6 cylinders outward to 10 to serve C (meanwhile H arrives).
At time 18, we seek 8 cylinders
Read MoreUnderstanding Cuts and Sections in Technical Drawing
Cuts and Sections in Technical Drawing
Court: Is the artifice by which, in the representation of a piece, we remove part of it to clarify and make easier its representation and dimensioning.
Section: Intersection of a cutting plane with a part (the area indicated in red). As seen when rendering a section, unlike a cut, it does not render the rest of the piece that is behind it. Whenever possible, we prefer to represent the section as it is a clearer and simpler representation.
Types of Cuts
- Total Cut:
Mechanical Fasteners and Dimensioning Standards
Dimensions
Dimensions should be placed in the most descriptive view of the feature being dimensioned. A feature should be dimensioned only once. Each feature should be dimensioned or identified with a note. Dimension features or surfaces should be done to a logical reference point. Center lines or center marks should be used on all circles, holes, and slots. Arrowheads are used to terminate dimension lines. The point of the arrowheads on the leader line must make contact with the feature line.