DRIVE MECHANISM

3.0 TYPES OF DRIVE MECHANISM

• BELT DRIVE
• CHAIN DRIVE
• GEAR DRIVE
• FRICTION DRIVE

3.1 BELT DRIVE

       3.1.1 V-BELTS

                Most V-belt drives used in industrial applications fall into two categories: heavy duty (industrial) and light duty (fractional horsepower). There are primarily two types of industrial belts: the classic cross sections (A, B, C, and D), which have been used for decades, and the narrow cross sections (3V, 5V,and 8V), which are relatively new. Most of the sections are available in banded (wrapped) and molded notch (cog) constructions. The banded belt has a fabric cover which completely encloses the exterior of the belt. 

Diagram 3.1.1A

Typical classic cross-sectional V-belt molded

notch construction.

Diagram 3.1 .1B 

Typical narrow cross-sectional V-belt,banded construction. 

     3.1.2 BELTS MAINTENANCE

        There are three possible causes of pulley misalignment:

1. Driver and driven shafts are not parallel.

2. Pulleys are not properly located axially on the shaft.

3. Pulleys are tilted due to improper mounting.

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        Belt tension may be summarized with a few simple rules:

1. The best tension for a V-belt is the lowest tension at which the belt will not slip at the                           highest load. Since synchronous belts are more sensitive to tension, use the force-                                 deflection numerical method described below and tension gauges to set tension for these                      belts.

2. When installing a new drive, set the tension, rotate the drive a few revolutions, and then                       recheck the tension. Check the tension once more after the first day of running.

3. For V-belt drives, check the belt tension periodically thereafter.