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14.1 CONNECTORS
À p14.1.1 Bearings
(|The interface between moving parts that should minimize friction and wear.
14.1.1.1 - Plain Bearings
´ ð´ 0Generally used in low speed machines.
The main bearing action comes from the lubricant.
This looks like a section of tube that is placed in a hole, and the shaft rotates inside.
Made for slowly rotating equipment
lubrication is required, and problems will arise when not properly maintained.
Used on large machines at low speeds.
The two halves of the bearings are adjusted in position using shims.
Oil grooves are used for lubrication.
Opposses axial thrusts of rotating shafts.
Uses shoes of a variety of shapes,
An oil wedge approach is used to support the bearing.
14.1.1.2 - Rolling Bearings
´ ð´ 0Low friction, high speeds, low loads.
ball bearings are packed between two rotating rings.
The grooves that contain the ball bearings is given different shapes for different loading conditions.
For heavy loads at medium or high speeds.
The various roller bearings are designed for loads (radial and axial) and packing space.
A set of rollers or balls are held between two washers.
Designed mainly for lower speed axial loads and occasionally light radial loads.
14.1.2 Threads
(|One of the classic forms of mechanical connector. Also used to magnify motion and force, and to convert rotation to linear motion.
Right hand threads are turned clockwise to tighten, left hand threads are turned the other way.
Threads Per Inch (TPI) are the number of turns of the thread per inch of length.
There are a number of standard threads, as outlined in the following subsections.
14.1.2.1 - Metric
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14.1.2.2 - American National Standard
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14.1.2.3 - British Standard Whitworth (BSW)
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14.1.2.4 - The Unified Thread
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14.1.2.5 - American National ACME Thread
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14.1.2.6 - Brown and Sharpe Worm Thread
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14.1.2.7 - Square Thread
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14.1.3 Tapers
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