Ex. 13. Give information about clutches using the table .

 

 

 

 

VI. Reading and comprehension

Ex. 14. Read and translate the text B without a dictionary for 10 minutes and explain the operation in automobile:

Text B

Operation in automobiles

 

In a car the clutch is operated by the left-most pedal using hydraulics or a cable connection from the pedal to the clutch mechanism. Even though the clutch may physically be located very close to the pedal, such remote means of actuation (or a multi-jointed linkage) are necessary to eliminate the effect of slight engine movement, engine mountings being flexible by design. With a rigid mechanical linkage, smooth engagement would be near-impossible, because engine movement inevitably occurs as the drive is "taken up." No pressure on the pedal means that the clutch plates are engaged (driving), while pressing the pedal disengages the clutch plates, allowing the driver to shift gears or coast.

A manual transmission contains cogs for selecting gears. These cogs have matching teeth, called dog teeth, which means that the rotation speeds of the two parts have a synchronizer, a device that uses frictional contact to bring the two parts to the same speed, and a locking mechanism called a blocker ring to prevent engagement of the teeth (full movement of the shift lever into gear) until the speeds are synchronized.

This plastic pilot shaft guide tool is used to align the clutch disk as the spring-loaded pressure plate is installed. The transmission's drive splines and pilot shaft have an identical shape. A number of such devices fit various makes and models of drivetrains

 

Non-powertrain in automobiles

There are other clutches found in a car. For example, a belt-driven engine cooling fan may have a clutch that is heat-activated. The driving and driven elements are separated by a silicone-based fluid and a valve controlled by a bimetallic spring. When the temperature is low, the spring winds and closes the valve, which allows the fan to spin at about 20% to 30% of the shaft speed. As the temperature of the spring rises, it unwinds and opens the valve, allowing fluid past the valve which allows the fan to spin at about 60% to 90% of shaft speed depending on whether it a regular or heavy-duty clutch. There are also electronically engaged clutches (such as for an air conditioning compressor) that use magnetic force to lock the drive and driven shafts together.

Operation in motorcycles

On most motorcycles, the clutch is operated by the clutch lever, located on the left handlebar. No pressure on the lever means that the clutch plates are engaged (driving), while pulling the lever back towards the rider will disengage the clutch plates, allowing the rider to shift gears. Motorcycle clutches are usually made up of a stack of alternating plain steel and friction plates. One type of plate has lugs on its inner diameter that key it to the engine crankshaft, while the other type of plate has lugs on its outer diameter that key it to a basket that turns the transmission input shaft. The plates are forced together by a set of coil springs when the clutch is engaged. Racing motorcycles often use slipper clutches to eliminate the effects of engine braking.

Centrifugal

Some cars and mopeds have a centrifugal clutch, using centrifugal effects to engage the clutch above certain rpm.

Notes:

To locate – визначати місцезнаходження

To actuate – приводити в дію

Linkage – зв'язок

To Occur – відбуватися

Inevitably – не мінуючи

Ex.15. Answer the following questions:

1. How is the clutch operated in the car?

2. What can you say about non-powertrain in automobiles?

3. What is the difference between operation in automobile and in motorcycles?

Ex.16. Render the text B using the plan of rendering on page 67.

 

Supplementary reading.

Texts for written translation with a dictionary

Read the texts and translate them in writing. Use a dictionary

Clutch

 

Clutch for a drive shaft: The clutch disc (center) spins with the flywheel (left). To disengage, the lever is pulled (black arrow), causing a white pressure plate (right) to disengage the green clutch disc from turning the drive shaft, which turns within the thrust-bearing ring of the lever. Never will all 3 rings connect, with no gaps.

 

A clutch is a mechanism for transmitting rotation, which can be engaged and disengaged. Clutches are useful in devices that have two rotating shafts. In these devices, one shaft is typically driven by a motor or pulley, and the other shaft drives another device. In a drill, for instance, one shaft is driven by a motor, and the other drives a drill chuck. The clutch connects the two shafts so that they can either be locked together and spin at the same speed (engaged), or be decoupled and spin at different speeds (disengaged).

Rear side of a Ford V6 engine, looking at the clutch housing on the flywheel