Читать книгу Farm Machinery and Equipment - Harris Pearson Smith - Страница 23

1. Enumerate the various methods of transmitting power in farm equipment. (a) Explain the merits of each method. (b) Explain the difference between a direct and a flexible shaft drive.

2. (a) Explain how the sizes of V belts are designated. (b) How is the pitch length designated? (c) Explain what is meant by a double-sided V belt.

3. The centers of two B-type V-belt sheaves are 24 inches apart. The drive sheave has a pitch diameter of 14 inches while the driven sheave has a pitch diameter of 5 inches. Find the length of V belt required. Take into consideration the installation take-up allowance.

4. Explain the differences between and the uses of (a) single sheave; (b), multiple sheave; (c) variable-speed sheave.

5. Under what conditions are the following used: (a) hook-link chain; (b) roller chain?

6. Enumerate the various types of gears and explain their special uses.

7. A tractor is used to operate the horizontal-rotating knives of a stalk cutter-shredder. The tractor power-take-off runs at 560 r.p.m. and drives a pinion gear with thirteen teeth. The driven gear has 24 teeth. (a) Find the r.p.m. of the knife blades. (b) Find the peripheral travel of the blade ends when cutting a circular pattern 57 inches in diameter.

8. Explain the functions of the universal joints in a power-take-off drive. What is the accepted standard size of a power-take-off shaft for tractors?

9. Explain the differences between the various types of clutches.

10. Explain the differences between and uses of the various types of bearings.

11. Enumerate the types of bolts, nuts, and screws.

¹ ASAE-SAE Standard, 1944.

¹ Power Take-off for Farm Tractors, Agr. Engin. Yearbook, 1954.