Basic Automobile Designer Interview Preparation Guide

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Chain dimensioning can be used where the possible accumulation of tolerance does not cause danger to the functional requirement of the part.

It is a curve which is generated by point moving so that the differences of the distances from any point of the curve to two fixed points(foci),is a constant equal to the transverse axis of the hyperbola.

This is drawn by using three axis. One axis is drawn vertically and the other two are at an angle of 30 degree (right and left) to the horizontal.

Drawing which shows how two or parts are assembled and identifies all the pieces which form the assembly is called assembly drawings.

A perspective drawing is one which more nearly present an object as seen in an actual photograph or as it appears to the eye of the observer.

It should be specify pitch and dimension with tolerances and also the distance to the end of full(parallel)threads.

Thin materials such as sheets, gaskets and electrical sections are shown solid in section and adjoining parts should be separated by a small space.

The top view appears above the front view with right side of the object to the right of the front view in third angle projection.

Involute is a spiral curve made by a point on a perfectly taut string as it unwinds from around a shape such as a circle or polygon.

These are thin lines composed of long dashes with pair of short dashes. Phantom Lines used to show adjacent parts, alternate positionsand the lines of motion.

Parabola is a curve which is generated by a point moving along a path equidistant from a point (focus)and a straight line(directrix).

This is expressed directly on the drawing which is essential to the function of the product.

Because it shows clearly the internal shape of an object or interior details of a part can easily shown.

Production drawings are the drawings which are required for the fabrication of any product.

It is a plane curve formed by a point moving so that the sum of its distances from two fixed points (foci) is constant and equal to major axis.

Representation of an object on paper is called projection of an object.

It is the plane on which the projection of the object is taken.

It is a graphic language of engineers which represents a real thing by means of picture view.

To make the appearance of a pictorial drawing more natural .

It is the one view projection where the projectors may be at any angle except 90 degree with the plane of projection, but 45 degree projectors are generally used because projectors at 45 degree with plane of projection all the edges of the cube are in their true lengths in the oblique projection.

☛ (a) Front view or Elevation
☛ (b) Top view or Plan
☛ (c) Side view

The piston head is designed on the basis of the following considerations:
☛ > The crown should have enough strength to absorb the explosion pressure inside the engine cylinder.
☛ > The head must always dissipate the heat of the explosion as quickly as possible to the engine walls. The thickness of the head is calculated on the basis of another formula which takes into consideration the heat flowing through the head, the conductivity factor of the material. The temperature at the center and edges of the head.
☛ > The thickness of the piston head is calculated on the basis of the Grashoff`s formula which takes into consideration the maximum gas pressure of an explosion , the permissible bending and the outside diameter of the piston.

Generally roller or hinged support are used to support the frames. The conditions of equilibrium are used to determine the reaction support of a frame. The condition of equilibrium takes place when the sum of the horizontal and vertical forces sum equal to zero. The system must form a state of equilibrium even after considering the external loads and the reactions at the supports. For equilibrium to be prevalent in the system the following conditions are required to be in occurrence:
☛ > Summation of V = 0. This implies that the summation of all the forces in the vertical direction results to zero.
☛ > Summation of H = 0 . This implies that the total of all the forces acting in horizontal direction is also zero.
☛ > Summation of M = 0. The sum of all the moment of forces around a point must be zero.

☛ 1. Parallel Line Development: It is used for patterns of prisms and cylinders.
☛ 2. Radial Line Development: This is used for surfaces of regular tapering forms such as pyramids and corns.
☛ 3. Triangulation Development: It is used when the connecting surface is neither prismatic nor pyramidal such as developing warped and double curved surfaces.

In first angle projection the top view is positioned below the front view with the left side view of the object to the right side of the front view.