REVERSE GEAR BOX FOR HANDICAPPED VEIHCLE

                         Introduction The previous normally applies only to the forward gears. The implementation of the reverse gear is usually different, implemented in the following way to reduce the cost of the transmission. Reverse is also a pair of gears: one gear on the countershaft and one on the output shaft. However, whereas all the forward gears are always meshed together, there is a gap between the reverse gears. Moreover, they are both attached to their shafts: neither one rotates freely about the shaft. When reverse is selected a small gear, called an idler gear or reverse idler, is slid between them. The idler has teeth which mesh with both gears, and thus it couples these gears together and reverses the direction of rotation without changing the gear ratio. Construction And Working In other words, when reverse gear is selected, it is in fact actual gear teeth that are being meshed, with no aid from a synchronization mechanism. For this reason, the output shaft must not be rotating when reverse is selected: the bike must be stopped. In order that reverse can be selected without grinding even if the input shaft is spinning inertially, there may be a mechanism to stop the input shaft from spinning. The driver brings the vehicle to a stop, and selects reverse. As that selection is made, some mechanism in the transmission stops the input shaft. Both gears are stopped and the idler can be inserted between them. There is a clear description of such a mechanism in the Manual, which refers to it as a "noise reduction system": Whenever the clutch pedal is depressed to shift into reverse, the mainshaft continues to rotate because of its inertia. The resulting speed difference between mainshaft and reverse idler gear produces gear noise [grinding]. The reverse gear noise reduction system employs a cam plate which was added to the reverse shift holder. When shifting into reverse, the 5th/reverse shift piece, connected to the shift lever, rotates the cam plate. This causes the synchro set to stop the rotating mainshaft. —A reverse gear implemented this way makes a loud whining sound, which is not normally heard in the forward gears. The teeth on the forward gears of most consumer automobiles are helically cut. When helical gears rotate, there is constant contact between gears, which results in quiet operation. In spite of all forward gears being always meshed, they do not make a sound that can be easily heard above the engine noise. By contrast, most reverse gears are spur gears, meaning that they have straight teeth, in order to allow for the sliding engagement of the idler, which is difficult with helical gears. The teeth of spur gears clatter together when the gears spin, generating a characteristic whine. Attempting to select reverse while the vehicle is moving forward causes severe gear wear (except in transmissions with synchromesh on the reverse gear). However, most manual transmissions have a many newer six-speed manual transmissions have a collar under the shift knob which must be lifted to engage reverse to also help prevent this. The spur gear design of reverse gear represents some compromises (less robust, unsynchronized engagement and loud noise) which are acceptable due to the relatively small amount of driving that takes place in reverse. The gearbox of the classic notable example of a gearbox with a helical reverse gear engaged in the same unsynchronized manner as the spur gears described above. Its design allows reverse to share cogs with first gear, and is exceptionally quiet, but results in difficult engagement and unreliable operation. However, many modern transmissions now include a reverse gear synchronizer and helical gearing. The gearbox provides a selection of gearsfor different driving conditions: standing start, climbing a hill, or cruising on level surfaces. The lower the gear, the slower the road wheels turn in relation to the engine speed. The constant-mesh gearbox Construction Of Various Parts: Gears Introduction The previous normally applies only to the forward gears. The implementation of the reverse gear is usually different, implemented in the following way to reduce the cost of the transmission. Reverse is also a pair of gears: one gear on the countershaft and one on the output shaft. However, whereas all the forward gears are always meshed together, there is a gap between the reverse gears. Moreover, they are both attached to their shafts: neither one rotates freely about the shaft. When reverse is selected a small gear, called an idler gear or reverse idler, is slid between them. The idler has teeth which mesh with both gears, and thus it couples these gears together and reverses the direction of rotation without changing the gear ratio. 


 Construction And Working 


 In other words, when reverse gear is selected, it is in fact actual gear teeth that are being meshed, with no aid from a synchronization mechanism. For this reason, the output shaft must not be rotating when reverse is selected: the car must be stopped. In order that reverse can be selected without grinding even if the input shaft is spinning inertially, there may be a mechanism to stop the input shaft from spinning. The driver brings the vehicle to a stop, and selects reverse. As that selection is made, some mechanism in the transmission stops the input shaft. Both gears are stopped and the idler can be inserted between them. There is a clear description of such a mechanism in the Manual, which refers to it as a "noise reduction system": Whenever the clutch pedal is depressed to shift into reverse, the mainshaft continues to rotate because of its inertia. The resulting speed difference between mainshaft and reverse idler gear produces gear noise [grinding]. The reverse gear noise reduction system employs a cam plate which was added to the reverse shift holder. When shifting into reverse, the 5th/reverse shift piece, connected to the shift lever, rotates the cam plate. This causes the synchro set to stop the rotating mainshaft. —A reverse gear implemented this way makes a loud whining sound, which is not normally heard in the forward gears. The teeth on the forward gears of most consumer automobiles are helically cut. When helical gears rotate, there is constant contact between gears, which results in quiet operation. In spite of all forward gears being always meshed, they do not make a sound that can be easily heard above the engine noise. By contrast, most reverse gears are spur gears, meaning that they have straight teeth, in order to allow for the sliding engagement of the idler, which is difficult with helical gears. The teeth of spur gears clatter together when the gears spin, generating a characteristic whine. Attempting to select reverse while the vehicle is moving forward causes severe gear wear (except in transmissions with synchromesh on the reverse gear). However, most manual transmissions have a many newer six-speed manual transmissions have a collar under the shift knob which must be lifted to engage reverse to also help prevent this. The spur gear design of reverse gear represents some compromises (less robust, unsynchronized engagement and loud noise) which are acceptable due to the relatively small amount of driving that takes place in reverse. The gearbox of the classic notable example of a gearbox with a helical reverse gear engaged in the same unsynchronized manner as the spur gears described above. Its design allows reverse to share cogs with first gear, and is exceptionally quiet, but results in difficult engagement and unreliable operation. However, many modern transmissions now include a reverse gear synchronizer and helical gearing. The gearbox provides a selection of gearsfor different driving conditions: standing start, climbing a hill, or cruising on level surfaces. The lower the gear, the slower the road wheels turn in relation to the engine speed.

How to make thermo accoustic refrigiration

 

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Bending machine using hydraulic jack

       


   The bending machine press are used to press sheet metal using normal hydraulic jack by pedal operated mechanism. IT Consists Hydraulic Jack And Press Tool . Hydraulic Jack Is Fixed Bottom Of the Tool .
   Hydraulic Jack Operating Handle Modified For Pedal Operating Mechanism.The hydraulic press depends on Pascal's principle: the pressure throughout a closed system is constant. One part of the system is a piston acting as a pump, with a modest mechanical force acting on a small cross-sectional area; the other part is a piston with a larger area which generates a correspondingly lagoogle.com, pub-5909580570280809, DIRECT, f08c47fec0942fa0rge mechanical force. Only small-diameter tubing (which more easily resists pressure) is needed if the pump is separated from the press cylinder.
Pascal's law: Pressure on a confined fluid is transmitted undiminished and acts with equal force on equal areas and at 90 degrees to the container wall.

A fluid, such as oil, is displaced when either piston is pushed inward. Since the fluid is incompressible, the volume that the small piston displaces is equal to the volume displaced by the large piston. This causes a difference in the length of displacement, which is proportional to the ratio of areas of the heads of the pistons given that volume = area X length. Therefore, the small piston must be moved a large distance to get the large piston to move significantly. The distance the large piston will move is the distance that the small piston is moved divided by the ratio of the areas of the heads of the pistons. This is how energy, in the form of work in this case, is conserved and the Law of Conservation of Energy is satisfied. Work is force applied over a distance, and since the force is increased on the larger piston, the distance the force is applied over must be decreased.

Pneumatic Shapper


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The shaper is a reciprocating type of machine tool intended primarily to produce flat surfaces. The metal working shaper was developed in the year 1836 by James Nasmyth an Englishman. The Shaper machine tool holds and locates a work piece on a table and machines or cuts the work piece by feeding it against a reciprocating single point cutting tool. When the horizontal surface is being machined the table automatically feeds the work to the cutting tool on each return stroke of google.com, pub-5909580570280809, DIRECT, f08c47fec0942fa0the ram. The surfaces cut by the shaper may be horizontal, vertical or inclined. Principal Parts of a Shaper: The following figure illustrates the different parts of a standard shaper.

Shaper Automation Using Electro-Pneumatic Devices and PLCs.
PLC TIMING SWICTH
                                   A time switch (also called timer switch or simply timer) is a timer that operates an electric switch controlled by the timing mechanism.
The switch may be connected to a circuit operating from mains power, or for lower-voltage circuits, including battery-operated equipment in vehicles. It may be built into power circuits (as with a central heating timer), plugged into a power point with equipment plugged into the timer instead of directly into the power point, or built into equipment as, for example, a sleep timer that turns off a television receiver after an interval.