A. Spur gears 1. Transmit motion between non-parallel and non-intersecting shafts B. Helical gears 2. Transmit motion between parallel shafts C. Worm gears D. Bevel gears 4. Transmit motion between parallel shafts or non-parallel
A – 2, B – 4, C – 1, D - 3
Gears are essential mechanical components used to transmit motion and power between rotating shafts. Different types of gears are designed for specific applications based on the orientation of the shafts they connect. Understanding these relationships is crucial in mechanical engineering.
Gear Types and Shaft Arrangements
Let's delve into the characteristics of each gear type and how they are matched with different shaft configurations:
- Spur Gears: These are the most common and simplest type of gears. They have straight teeth cut parallel to the axis of the gear. Due to their design, spur gears are primarily used for transmitting motion between shafts that are parallel to each other. They are known for their efficiency and are found in various applications like washing machines, clocks, and simple gear trains.
- Helical Gears: Unlike spur gears, helical gears have teeth that are cut at an angle (helix) to the axis of the gear. This angled tooth engagement provides a smoother and quieter operation compared to spur gears, as multiple teeth engage simultaneously. Helical gears are versatile and can transmit motion between parallel shafts. Additionally, when arranged in a crossed configuration, they can also transmit motion between non-parallel and non-intersecting shafts.
- Worm Gears: A worm gear system consists of a worm (which looks like a screw) and a worm wheel (a spur or helical gear that mates with the worm). This combination is highly effective for achieving large speed reductions in a compact space. Worm gears are specifically used for transmitting motion between shafts that are non-parallel and non-intersecting, typically with their axes at 90 degrees. They also offer a self-locking feature in many applications, meaning the worm wheel cannot drive the worm.
- Bevel Gears: Bevel gears are conically shaped, and their teeth are cut on the conical surface. They are designed to transmit motion between shafts that intersect each other. The angle of intersection can vary, but 90 degrees is the most common. Bevel gears are commonly found in differentials of automobiles and in machinery where power needs to be turned around a corner.
Matching Gear Types with Shaft Orientations
Based on the descriptions above, we can establish the correct matches:
| Gear Type | Shaft Arrangement for Motion Transmission | Match |
|---|---|---|
| A. Spur gears | Transmit motion between parallel shafts | A – 2 |
| B. Helical gears | Transmit motion between parallel shafts or non-parallel | B – 4 |
| C. Worm gears | Transmit motion between non-parallel and non-intersecting shafts | C – 1 |
| D. Bevel gears | Transmit motion between intersecting shafts | D – 3 |
Therefore, the correct combination is A – 2, B – 4, C – 1, D – 3.
Important Questions from Gear
Gear teeth are made harder to avoid
To nullify the thrust on the shaft, we use
Match the following columns their areas of of gear names and their areas of application.
Column I Column II 1. Rack Gear A. Reduction Gearing for ships 2. Screw Gear B. Anti-reversing gear device 3. Spiral Bevel Gear C. Printing Press 4. Worm Gear Pair D. Automobile engines _____ motion is transmitted between the teeth of gears in mesh.
The two main advantages of using helical gears rather than spur gears in a transmission system are
