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Charlie Pace
Charlielost.PNG
Dominic Monaghan as Charlie Pace
First appearance "Pilot: Part 1"
Centric
episode(s)
"Pilot, Part 2"
"The Moth"
"Homecoming"
"Exodus, Part 2"
"Fire and Water"
"Greatest Hits"
Information
Name Charlie Pace
Age 25
Former
residence
Manchester, England, UK
(Former) profession - Rock musician
Portrayed by Dominic Monaghan

Charlie Hieronymus Pace is a fictional character on the ABC television series Lost, chronicling the lives of plane crash survivors on a mysterious tropical island.[1] Played by Dominic Monaghan,[2] Charlie was a regular character in the first three seasons until the character's death in the season three finale. Monaghan was later billed as a guest star in season four. Introduced in the pilot episode, Charlie battles with an addiction to heroin in the first two seasons, before he finally lays his demons aside, establishing a relationship with Claire Littleton (Emilie de Ravin) and her son Aaron. In season three of the show, Charlie had to face his own mortality when Desmond Hume (Henry Ian Cusick) repeatedly foresaw his death. Flashbacks from the series show Charlie was a member of a rock band named DriveSHAFT.

Contents

Arc

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Prior to the Crash

Charlie was born in 1979 to Simon and Megan Pace, and lived in Manchester, England. When Charlie was young, he was given a piano as a gift on Christmas Day, thus beginning his career in music. Charlie honed his musical talents by playing on the street for money, where he spotted a woman being mugged (who turned out to be Sayid's beloved, Nadia) and saved her, prompting her to call him a hero.

Sometime later, Charlie and his brother Liam had formed a band called Driveshaft, and landed a record deal. Suddenly, Driveshaft became extremely popular, although they were a one hit wonder band. Liam, amidst their popularity and success, turned to heroin. On Christmas Day, while touring Finland, Liam gave Charlie his D.S. family ring, saying that because of his addiction he would never have a family so it should go to Charlie. Eventually, though, Charlie became addicted to heroin. As the band's fame began to decrease, Charlie sank further into his addiction. Liam sold his piano so he could enroll into rehabilitation, after dropping his newborn daughter. Liam left Charlie alone, in order to be with his wife, Karen, and daughter, Megan (named after the brothers' mother).

With Driveshaft disbanded, Charlie resorted to theft to support his heroin addiction. He charmed a wealthy woman, Lucy, in order to rob her, but she learned of his intentions and left him as he began to develop real feelings for her. Charlie then traveled to Australia to persuade a sober Liam to rejoin the band. Liam refused, offering instead to help him enter a rehabilitation program, but Charlie angrily refused and left to board a plane to Los Angeles the next day. The night before the flight, he took heroin with a woman named Lily, who he fought with over the last of the stash until she left angrily. On the plane, he struggles without any heroin and goes to the bathroom to take some, when the plane begins to crash.

After the Crash

On the second day on the island, he, Jack Shephard and Kate Austen venture inland to the plane's cockpit, where he retrieves his stash of heroin.[3] John Locke later discovers his addiction to heroin and in exchange for his guitar, Charlie gives up the drugs.[4] After Jack is trapped in a cave-in, Charlie saves him. Afterwards, Charlie burns his drugs in a fire.[5] When Charlie tries to stop Claire from going back to the beach, both are kidnapped by Ethan Rom.[6] Pursuing him, Jack and Kate find Charlie hung from a tree almost dead.[7] When Claire returns and Ethan comes to recapture her, Charlie kills the latter with a gun.[8]

When Claire goes into labour, Charlie, along with Jin-Soo Kwon, helps Kate deliver the baby.[9] When Danielle Rousseau abducts the baby, named Aaron, Charlie and Sayid Jarrah go to rescue him.[10] Along the way, Charlie and Sayid stop by a beechcraft carrying several Virgin Mary statues filled with heroin. That night, Charlie and Sayid manage to reclaim Aaron, and bring him safely back to Claire.[11]

In Season 2, Mr. Eko reveals to Claire the contents of the Virgin Mary statue, creating a rift between her and Charlie. Charlie takes Eko to the beechcraft where he found them, and the two decide to burn the plane and its contents. However, Charlie secretly keeps a stash hidden in the jungle.[12] Later, he begins experiencing surreal dreams, in which Aaron is in peril. He seeks out Eko, who says Aaron may need to be baptized. Subsequently, Charlie kidnaps Aaron and attempts to baptize him. When caught, Locke assaults him.[13] As retribution for Locke embarrassing him, Charlie aids Sawyer in conning Jack and Locke out of the Hatch's guns and heroin by assaulting Sun.[14]

Later, Sayid tells Charlie about a prisoner in the Hatch, "Henry Gale". They, along with Ana-Lucia Cortez, attempt to find the balloon that Henry allegedly crashed in. When the three return to the Hatch, they reveal Henry to be an impostor.[15] After this, Charlie begins helping Eko build a church, but is angered when Eko abandons its construction. He finds a box of vaccine, and gives it to Claire for herself and Aaron, beginning to renew their friendship. In Sawyer's tent, Charlie discovers the remaining Virgin Mary statues, and throws them in the ocean. Eko seeks his help in finding the dynamite from the Black Rock ship. Charlie brings him to it, and he and Eko go to the Hatch, with Eko intending to blow open the blast door. After an explosion, Charlie barely escapes the Hatch as it implodes.[16] After the Hatch's implosion, Charlie helps Locke standing guard while Locke communes with the island and helping him rescue Eko from a polar bear's cave.[17] After Eko's death, Desmond starts having visions in which Charlie dies.[18]

Later, Charlie joins Desmond, Hurley and Jin on a hike into the jungle where they find a parachutist named Naomi Dorrit, who crashed on the island.[19] When Jack announces his plan to foil the others and contact the outside world, Charlie volunteers to swim down to the Looking Glass station and switch off a device blocking transmissions to and from the island. Desmond accompanies him.[20] He confronts three people, two females who maintain the island and Mikhail. During a confrontation, Mikhail is shot in the chest with a spear gun. Just as Charlie is able to make contact with Penelope Widmore in a sideroom, a mysteriously resurrected Mikhail uses a grenade to destroy the room's porthole. It floods. To spare Desmond he locks the door, and warns him of Naomi's deception.[21]

After leaving the island, Hurley has visions of Charlie first at a convenience store, and then later at the asylum Hurley has been committed to. Charlie tells Hurley the people remaining on the island need him, and that he has to return, but disappears when Hurley closes his eyes.[22] In "Something Nice Back Home", Hurley conveys to Jack a message from Charlie: "You're not supposed to raise him". Hurley also tells Jack that Charlie states he will be visited.

Alternate Timeline

In the episode "LA X", Charlie is seen on board Oceanic 815, in the restroom with heroin, as seen in the "Pilot" episode. However; during this "flash-sideways", flight 815 does not crash, and Charlie gets a small bag of heroin lodged in his throat, rendering him unconscious. He is revived by Jack and later arrested for possession of illegal drugs. Glaring at Jack as he is restrained, he snarls "I was meant to die." In the episode Recon, Charlie's brother, Liam, was at a police station, the same one Sawyer and Miles work at, and asking about Charlie. [23]

Development

After appearing in The Lord of the Rings, Dominic Monaghan was offered many fantasy-based roles, like elves and pixies. He was keen to portray a different role, so he wanted a contemporary part that had layers and an edge. Originally Charlie was an older rocker that has been a big hit in the 1980s but now had a heroin addiction. After the producers enjoyed Monaghan's audition where he read Sawyer's lines, they rewrote the part to make him a young has-been.[24]

Charlie (Hieronymus) Pace is named after the Austrian theologian and historian Hieronymus Pez. This is in keeping with many of the characters in Lost who are named after famous philosophers and theologians.

In a DVD commentary for "The Moth", Monaghan said that he felt Charlie's black hoodie is some sort of "security blanket" that he hides underneath and uses when he feels "lost".[25]

DriveSHAFT was the fictional band in "Lost" formed by Charlie and his older brother Liam. The band was named after the duo's great-grandfather "Dexter Stratton"; thus the DS initials of the group. In a Season One DVD Featurette, "Backstage with Driveshaft", Dominic Monaghan cites them as a direct influence on the fictional band:

What I think Charlie gets confused with is this idea that being on TRL a couple of times in America and maybe being in the Top 20 and having a little run of things over the summer, he thought they were turning into the new Radiohead or the new Oasis or the new Verve.

In a Season One DVD Featurette named "Backstage with Driveshaft", Dominic Monaghan says that:

I think Charlie thinks that his band is a little bit more important than they actually are. He's under the impression that his first album was kind of like Oasis' first album. Y'know, critically acclaimed, didn't sell big numbers, but y'know, in the industry, people gave it respect.

At the 2009 San Diego Comic-Con, Dominic Monaghan returned and confirmed he will be back in Lost's Final Season as Charlie Pace for three episodes.[26]

Reception

"No longer are we observing the ex-rocker, the junky, the Laurel to Hurley's Hardy, now we are seeing Charlie as vulnerable and complex human being with a galvanized sense of what makes life worth living."
— Jon Lachonis regarding Charlie in "Greatest Hits" .[27]

Chris Carabott responded positively to the utilization of the character in "The Moth", mentioning that, "Dini and Johnson use the various talents of some of the "losties" to further emphasise Charlie's uselessness" and that "Charlie's development throughout the episode is striking." However, he did express dissatisfaction at how he was used in season two, believing that it took plenty away from a "gem of an episode." In "Homecoming", he commented on his "good nature" and mentioned that his flashback "does a great job of contrasting the Charlie we now know on the island."

In his review of "Live Together, Die Alone", Scott Brown of Entertainment Weekly said that the writers were "trying to make us hate Charlie." calling him "deeply annoying".[28]

In a review of season three's penultimate episode, Chris Carabott said Charlie's flashbacks could "send shivers up our collective spines," and said he was "annoying at times." Nonetheless, he called the character "someone we can respect." Entertainment Weekly's Jeff Jensen said Charlie "was ready for the spotlight", and that Monaghan gave his "best performance yet"."[29] On BuddyTV, his flashbacks were described as bringing audiences "closer to Charlie's human aspect", and it was noted that the episode was "wildly successful" in turning Charlie into a relatable character.[27]

The website Television Without Pity ranked him 7th in a list of Lost's "10 Most Worthless Characters", dubbing his backstory "Oasis: Behind the Music".[30] Contrastingly, in a list of the show's "10 Best Backstories", he was ranked 8th.[31] A poll by E! Online named him as the character fans would most like to see return at 43.4% of the vote, with over 30% more votes than his nearest rival.[32]

References

  1. ^ Fordis, Jeff, (January 22, 2007) "ABC Studios Lost Show Description Lead Press Release Page," ABC Medianet. Retrieved on April 8, 2007.
  2. ^ Fordis, Jeff, (September 21, 2004) "ABC Television Studio Lost September 22, 2004 Episode "Pilot" Entertainment Press Release," ABC Medianet. Retrieved on February 1, 2009.
  3. ^ "Pilot: Part 2". J. J. Abrams, Writ. J. J. Abrams, Damon Lindelof & Jeffrey Lieber (story) and J. J. Abrams & Damon Lindeloff, (teleplay). Lost. ABC. 2004-09-29. No. 2, season 1.
  4. ^ "House of the Rising Sun". Michael Zinberg, Writ. Javier Grillo-Marxuach. Lost. ABC. 2004-10-27. No. 6, season 1.
  5. ^ "The Moth". Jack Bender, Writ. Jennifer Johnson & Paul Dini. Lost. ABC. 2004-11-03. No. 7, season 1.
  6. ^ "Raised by Another". Marita Grabiak, Writ. Lynne E. Litt. Lost. ABC. 2004-12-01. No. 10, season 1.
  7. ^ "All The Best Cowboys Have Daddy Issues". Stephen Williams, Writ. Javier Grillo-Marxuach. Lost. ABC. 2004-12-08. No. 11, season 1.
  8. ^ "Homecoming". Kevin Hooks, Writ. Damon Lindelof. Lost. ABC. 2005-02-09. No. 15, season 1.
  9. ^ "Do No Harm". Stephen Williams, Writ. Janet Tamaro. Lost. ABC. 2005-04-06. No. 20, season 1.
  10. ^ "Exodus: Part 1". Jack Bender, Writ. Damon Lindelof & Carlton Cuse. Lost. ABC. 2005-05-18. No. 23, season 1.
  11. ^ "Exodus: Part 2". Jack Bender, Writ. Damon Lindelof & Carlton Cuse. Lost. ABC. 2005-05-25. No. 24, season 1.
  12. ^ "The 23rd Psalm". Matt Earl Beesley, Writ. Damon Lindelof & Carlton Cuse. Lost. ABC. 2006-01-11. No. 10, season 2.
  13. ^ "Fire + Water". Jack Bender, Writ. Edward Kitsis & Adam Horowitz. Lost. ABC. 2006-01-25. No. 12, season 2.
  14. ^ "The Long Con". Roxann Dawson, Writ. Steven Maeda & Leonard Dick. Lost. ABC. 2006-02-08. No. 13, season 2.
  15. ^ "Lockdown". Stephen Williams, Writ. Damon Lindelof & Carlton Cuse. Lost. ABC. 2006-03-29. No. 17, season 2.
  16. ^ "Live Together, Die Alone". Jack Bender, Writ. Damon Lindelof & Carlton Cuse. Lost. ABC. 2006-05-24. No. 23, season 2.
  17. ^ "Further Instructions". Stephen Williams, Writ. Carlton Cuse & Elizabeth Sarnoff. Lost. ABC. 2006-10-18. No. 3, season 3.
  18. ^ "Flashes Before Your Eyes". Jack Bender, Writ. Damon Lindelof & Drew Goddard. Lost. ABC. 2007-02-14. No. 8, season 3.
  19. ^ "The Man Behind the Curtain". Bobby Roth, Writ. Elizabeth Sarnoff & Drew Goddard. Lost. ABC. 2007-05-09. No. 20, season 3.
  20. ^ "Greatest Hits". Stephen Williams, Writ. Edward Kitsis & Adam Horowitz. Lost. ABC. 2007-05-16. No. 21, season 3.
  21. ^ "Through the Looking Glass". Jack Bender, Writ. Carlton Cuse & Damon Lindelof. Lost. ABC. 2007-05-23. No. 22, season 3.
  22. ^ "The Beginning of the End". Jack Bender, Writ. Damon Lindelof & Carlton Cuse. Lost. ABC. 2008-01-31. No. 1, season 4.
  23. ^ "LA X". Jack Bender, Writ. Damon Lindelof & Carlton Cuse. Lost. ABC. 2010-02-02. No. 105, season 6.
  24. ^ "Before They Were Lost". Lost: The Complete First Season, Buena Vista Home Entertainment. September 6, 2005. Featurette, disc 7.
  25. ^ commentary for The Moth - Season 1 DVD
  26. ^ http://g4tv.com/videos/40223/Lost_Cast_Interviews/
  27. ^ a b Lachonis, Jon "DocArzt", (May 16, 2007) "3.21 'Greatest Hits' Recap", BuddyTV. Retrieved on December 3, 2007.
  28. ^ Brown, Scott (2006-05-25). "Live Together, Die Alone, Part 1 #223". Entertainment Weekly. http://www.ew.com/ew/allabout/episodes/0,,20000067_1197920,00.html. Retrieved 2008-08-11. 
  29. ^ Jensen, Jeff "Doc", (May 17, 2007) "Charlie Risks His Life", Entertainment Weekly. Retrieved on December 1, 2007.
  30. ^ "Lost: The 10 Most Worthless Characters". Television Without Pity. http://www.televisionwithoutpity.com/show/lost/lost_the_10_most_worthless_cha.php. Retrieved 2009-03-07. 
  31. ^ "10Best Backstories". Television Without Pity. http://www.televisionwithoutpity.com/show/lost/lost_the_10_best_backstories.php. Retrieved 2009-03-07. 
  32. ^ http://uk.eonline.com/uberblog/watch_with_kristin/b129364_spoiler_chat_will_lost_bring_dominic.html

External links


s at each end and a spline in the center]]


A drive shaft, driving shaft, propeller shaft, or Cardan shaft is a mechanical component for transmitting torque and rotation, usually used to connect other components of a drive train that cannot be connected directly because of distance or the need to allow for relative movement between them.

Drive shafts are carriers of torque: they are subject to torsion and shear stress, equivalent to the difference between the input torque and the load. They must therefore be strong enough to bear the stress, whilst avoiding too much additional weight as that would in turn increase their inertia.

Drive shafts frequently incorporate one or more universal joints or jaw couplings, and sometimes a splined joint or prismatic joint to allow for variations in the alignment and distance between the driving and driven components.

Contents

History

The term drive shaft first appeared during the mid 19th century. In Storer's 1861 patent reissue for a planing and matching machine, the term is used to refer to the belt-driven shaft by which the machine is driven.[1] The term is not used in his original patent.[2] Another early use of the term occurs in the 1861 patent reissue for the Watkins and Bryson horse-drawn mowing machine.[3] Here, the term refers to the shaft transmitting power from the machine's wheels to the gear train that works the cutting mechanism.

In the 1890s, the term began to be used in a manner closer to the modern sense. In 1891, for example, Battles referred to the shaft between the transmission and driving trucks of his Climax locomotive as the drive shaft,[4] and Stillman referred to the shaft linking the crankshaft to the rear axle of his shaft-driven bicycle as a drive shaft.[5] In 1899, Bukey used the term to describe the shaft transmitting power from the wheel to the driven machinery by a universal joint in his Horse-Power.[6] In the same year, Clark described his Marine Velocipede using the term to refer to the gear-driven shaft transmitting power through a universal joint to the propeller shaft.[7] Crompton used the term to refer to the shaft between the transmission of his steam-powered Motor Vehicle of 1903 and the driven axle.[8]

Automotive drive shafts

Vehicles

An automobile may use a longitudinal shaft to deliver power from an engine/transmission to the other end of the vehicle before it goes to the wheels. A pair of short drive shafts is commonly used to send power from a central differential, transmission, or transaxle to the wheels.

Front-engine, rear-wheel drive

In front-engined, rear-drive vehicles, a longer drive shaft is also required to send power the length of the vehicle. Two forms dominate: The torque tube with a single universal joint and the more common Hotchkiss drive with two or more joints. This system became known as Système Panhard after the automobile company Panhard et Levassor patented it.

Most of these vehicles have a clutch and gearbox (or transmission) mounted directly on the engine with a drive shaft leading to a final drive in the rear axle. When the vehicle is stationary, the drive shaft does not rotate. A few, mostly sports, cars seeking improved weight balance between front and rear, and most commonly Alfa Romeos or Porsche 924s, have instead used a rear-mounted transaxle. This places the clutch and transmission at the rear of the car and the drive shaft between them and the engine. In this case the drive shaft rotates continuously as long as the engine does, even when the car is stationary and out of gear.

Early automobiles often used chain drive or belt drive mechanisms rather than a drive shaft. Some used electrical generators and motors to transmit power to the wheels.

Front-wheel drive

In British English, the term "drive shaft" is restricted to a transverse shaft that transmits power to the wheels, especially the front wheels. A drive shaft connecting the gearbox to a rear differential is called a propeller shaft, or prop-shaft. A prop-shaft assembly consists of a propeller shaft, a slip joint and one or more universal joints. Where the engine and axles are separated from each other, as on four-wheel drive and rear-wheel drive vehicles, it is the propeller shaft that serves to transmit the drive force generated by the engine to the axles.

A drive shaft connecting a rear differential to a rear wheel may be called a half shaft. The name derives from the fact that two such shafts are required to form one rear axle.

Several different types of drive shaft are used in the automotive industry:

  • One-piece drive shaft
  • Two-piece drive shaft
  • Slip-in-tube drive shaft

The slip-in-tube drive shaft is a new type that also helps in crash energy management. It can be compressed in the event of a crash, so is also known as a collapsible drive shaft.

Four wheel and all-wheel drive

These evolved from the front-engine rear-wheel drive layout. A new form of transmission called the transfer case was placed between transmission and final drives in both axles. This split the drive to the two axles and may also have included reduction gears, a dog clutch or differential. At least two drive shafts were used, one from the transfer case to each axle. In some larger vehicles, the transfer box was centrally mounted and was itself driven by a short drive shaft. In vehicles the size of a Land Rover, the drive shaft to the front axle is noticeably shorter and more steeply articulated than the rear shaft, making it a more difficult engineering problem to build a reliable drive shaft, and which may involve a more sophisticated form of universal joint.

Modern light cars with all-wheel drive (notably Audi or the Fiat Panda) may use a system that more closely resembles a front-wheel drive layout. The transmission and final drive for the front axle are combined into one housing alongside the engine, and a single drive shaft runs the length of the car to the rear axle. This is a favoured design where the torque is biased to the front wheels to give car-like handling, or where the maker wishes to produce both four-wheel drive and front-wheel drive cars with many shared components.

Drive shaft for Research and Development (R&D)

The automotive industry also uses drive shafts at testing plants. At an engine test stand a drive shaft is used to transfer a certain speed / torque from the Internal combustion engine to a dynamometer. A "shaft guard" is used at a shaft connection to protect against contact with the drive shaft and for detection of a shaft failure. At a transmission test stand a drive shaft connects the prime mover with the transmission.

Motorcycle drive shafts

, Belgium, 4cylinders and shaft drive]] , with a shaft-drive, boxer twin engine]] Drive shafts have been used on motorcycles almost as long as there have been motorcycles. As an alternative to chain and belt drives, drive shafts offer relatively maintenance-free operation and long life. A disadvantage of shaft drive on a motorcycle is that gearing or a Hobson's joint or similar is needed to turn the power 90° from the shaft to the rear wheel, losing some power in the process. On the other hand, it is easier to protect the shaft linkages and drive gears from dust, sand and mud.

The best known motorcycle manufacturer to use shaft drive for a long time—since 1923—is BMW. Among contemporary manufacturers, Moto Guzzi is also well-known for its shaft drive motorcycles. The British company, Triumph and all four Japanese brands, Honda, Suzuki, Kawasaki and Yamaha, have produced shaft drive motorcycles. All geared models of the Vespa scooter produced to date have been shaft-driven. The automatic models, however, use a belt.

Motorcycle engines positioned such that the crankshaft is longitudinal and parallel to the frame are often used for shaft driven motorcycles. This requires only one 90° turn in power transmission, rather than two. Bikes from Moto Guzzi and BMW, plus the Triumph Rocket III and Honda ST series all use this engine layout.

Motorcycles with shaft drive are subject to shaft effect where the chassis climbs when power is applied. This is counteracted with systems such as BMW's Paralever, Moto Guzzi's CARC and Kawasaki's Tetra Lever.

Marine drive shafts

On a power-driven ship, the drive shaft, or propeller shaft, usually connects the transmission inside the vessel directly to the propeller, passing through a stuffing box or other seal at the point it exits the hull. There is also a thrust block, a bearing to resist the axial force of the propeller. As the rotating propeller pushes the vessel forward, any length of drive shaft between propeller and thrust block is subject to compression, and when going astern to tension. Except for the very smallest of boats, this force isn't taken on the gearbox or engine directly.

Cardan shafts are also often used in marine applications between the transmission and either a propeller gearbox or waterjet.

Locomotive drive shafts

File:Forks, Washington Shay Locomotive
The rear drive shaft, crankshaft and front drive shaft of a Shay locomotive.

The Shay, Climax and Heisler locomotives, all introduced in the late 19th century, used quill drives to couple power from a centrally mounted multi-cylinder engine to each of the trucks supporting the engine. On each of these geared steam locomotives, one end of each drive shaft was coupled to the driven truck through a universal joint while the other end was powered by the crankshaft, transmission or another truck through a second universal joint. A quill drive also has the ability to slide lengthways, effectively varying its length. This is required to allow the bogies to rotate when passing a curve.

Cardan shafts are used in some diesel locomotives (mainly diesel-hydraulics, such as British Rail Class 52) and some electric locomotives (e.g. British Rail Class 91). They are also widely used in diesel multiple units.

Drive shafts in Bicycles

.]] The drive shaft has served as an alternative to a chain-drive in bicycles for the past century, although never becoming very popular. A shaft-driven bicycle is described as an "Acatane", from one of their early makers. When used on a bicycle, a drive shaft has several advantages and disadvantages:

Advantages

  • Drive system is less likely to become jammed or broken, a common problem with chain-driven bicycles
  • The use of a gear system creates a smoother and more consistent pedaling motion
  • The rider cannot become dirtied from chain grease or injured by the chain from "Chain bite", which occurs when clothing or even a body part catches between the chain and a sprocket
  • Lower maintenance than a chain system when the drive shaft is enclosed in a tube, the common convention
  • More consistent performance. Dynamic Bicycles claims that a drive shaft bicycle consistently delivers 94% efficiency, whereas a chain-driven bike can deliver anywhere from 75-97% efficiency based on condition.
  • Greater clearance: with the absence of a derailleur or other low-hanging machinery, the bicycle has nearly twice the ground clearance
  • For bicycle rental companies, a drive-shaft bicycle is less prone to be stolen, since the shaft is non-standard, and both noticeable and non-maintainable. This type of bicycle is in use in several major cities of Europe, where there have been large municipal funded, public (and automatic) bicycle rental projects.[citation needed]

Disadvantages

  • A drive shaft system weighs more than a chain system, usually 1-2 pounds heavier
  • At optimum upkeep, a chain delivers greater efficiency
  • Many of the advantages claimed by drive shaft's proponents can be achieved on a chain-driven bicycle, such as covering the chain and gears with a metal or plastic cover
  • Use of lightweight derailleur gears with a high number of ratios is impossible, although hub gears can be used
  • Wheel removal can be complicated in some designs (as it is for some chain-driven bicycles with hub gears).

References

  1. ^ Henry D. Stover, Improvement in Wood-Planing Machines, U.S. Patent Reissue 1,190, May 21, 1861.
  2. ^ Henry D. Stover, Planing Machine, U.S. Patent 30,993, Dec. 18, 1860, 1861.
  3. ^ John DeLancy Watkins and Robert Bryson, Mowing Machines, U.S. Patent Reissue 1,904, July 23, 1861.
  4. ^ Rush S. Battles, Locomotive, U.S. Patent 455,154, June 30, 1891.
  5. ^ Walter Stillman, Bicycle, U.S. Patent 456,387, July 21, 1891.
  6. ^ Dudley D. Bukey, Horse-Power, U.S. Patent 631,198, Aug. 15, 1899.
  7. ^ Charles Clark, Marine Velocipede, [U.S. Patent 637,547], Nov. 21, 1899.
  8. ^ Charles Crompton, Motor-Vehicle U.S. Patent 718,097, Jan. 1903.

See also


]] A drive shaft, driving shaft, propeller shaft, or Cardan shaft is a mechanical component for transmitting torque and rotation, usually used to connect other components of a drive train that cannot be connected directly because of distance or the need to allow for relative movement between them.

Drive shafts are carriers of torque: they are subject to torsion and shear stress, equivalent to the difference between the input torque and the load. They must therefore be strong enough to bear the stress, whilst avoiding too much additional weight as that would in turn increase their inertia.

Contents

Automotive drive shafts

Vehicles

An automobile may use a longitudinal shaft to deliver power from an engine/transmission to the other end of the vehicle before it goes to the wheels. A pair of short drive shafts is commonly used to send power from a central differential, transmission, or transaxle to the wheels.

Front-engine, rear-wheel drive

In front-engined, rear-drive vehicles, a longer drive shaft is also required to send power the length of the vehicle. Two forms dominate: The torque tube with a single universal joint and the more common Hotchkiss drive with two or more joints. This system became known as Système Panhard after the automobile company Panhard et Levassor patented it.

Most of these vehicles have a clutch and gearbox (or transmission) mounted directly on the engine with a drive shaft leading to a final drive in the rear axle. When the vehicle is stationary, the drive shaft does not rotate. A few, mostly sports, cars seeking improved weight balance between front and rear, and most commonly Alfa Romeos or Porsche 924s, have instead used a rear-mounted transaxle. This places the clutch and transmission at the rear of the car and the drive shaft between them and the engine. In this case the drive shaft rotates continuously as long as the engine does, even when the car is stationary and out of gear.

Early automobiles often used chain drive or belt drive mechanisms rather than a drive shaft. Some used electrical generators and motors to transmit power to the wheels.

Front-wheel drive

In British English, the term "drive shaft" is restricted to a transverse shaft that transmits power to the wheels, especially the front wheels. A drive shaft connecting the gearbox to a rear differential is called a propeller shaft, or prop-shaft. A prop-shaft assembly consists of a propeller shaft, a slip joint and one or more universal joints. Where the engine and axles are separated from each other, as on four-wheel drive and rear-wheel drive vehicles, it is the propeller shaft that serves to transmit the drive force generated by the engine to the axles.

A drive shaft connecting a rear differential to a rear wheel may be called a half shaft. The name derives from the fact that two such shafts are required to form one rear axle.

Several different types of drive shaft are used in the automotive industry:

  • 1-piece drive shaft
  • 2-piece drive shaft
  • Slip-in-tube drive shaft

The slip-in-tube drive shaft is a new type that also helps in crash energy management. It can be compressed in the event of a crash, so is also known as a collapsible drive shaft.

Four wheel and all-wheel drive

These evolved from the front-engine rear-wheel drive layout. A new form of transmission called the "transfer box" was placed between transmission and final drives in both axles. This split the drive to the two axles and may also have included reduction gears, a dog clutch or differential. At least two drive shafts were used, one from the transfer box to each axle. In some larger vehicles, the transfer box was centrally mounted and was itself driven by a short drive shaft. In vehicles the size of a Land Rover, the drive shaft to the front axle is noticeably shorter and more steeply articulated than the rear shaft, making it a more difficult engineering problem to build a reliable drive shaft, and which may involve a more sophisticated form of universal joint.

Modern light cars with all-wheel drive (notably Audi or the Fiat Panda) may use a system that more closely resembles a front-wheel drive layout. The transmission and final drive for the front axle are combined into one housing alongside the engine, and a single driveshaft runs the length of the car to the rear axle. This is a favoured design where the torque is biased to the front wheels to give car-like handling, or where the maker wishes to prroduce both four-wheel drive and front-wheel drive cars with many shared components.

Drive shaft for Research and Development (R&D)

The automotive industry also uses drive shafts at testing plants. At an engine test stand a drive shaft is used to transfer a certain speed / torque from the combustion engine to a dynamometer. A "shaft guard" is used at a shaft connection to protect against contact with the drive shaft and for detection of a shaft failure. At a transmission test stand a drive shaft connects the prime mover with the transmission.

Motorcycle drive shafts

, Belgium, 4cylinders and shaft drive]] , with a shaft-drive, boxer twin engine]] Drive shafts have been used on motorcycles almost as long as there have been motorcycles. As an alternative to chain and belt drives, drive shafts offer relatively maintenance-free operation and long life. A disadvantage of shaft drive on a motorcycle is that gearing is needed to turn the power 90° from the shaft to the rear wheel, losing some power in the process. On the other hand, it is easier to protect the shaft linkages and drive gears from dust, sand and mud.

The best known motorcycle manufacturer to use shaft drive for a long time — since 1923 — is BMW. Among contemporary manufacturers, Moto Guzzi is also well-known for its shaft drive motorcycles. The British company, Triumph and all four Japanese brands, Honda, Suzuki, Kawasaki and Yamaha, have produced shaft drive motorcycles.

Motorcycle engines positioned such that the crankshaft is longitudinal and parallel to the frame are often used for shaft driven motorcycles. This requires only one 90° turn in power transmission, rather than two. Moto Guzzi, BMW, Triumph, and Honda use this engine layout.

Motorcycles with shaft drive are subject to shaft effect where the chassis climbs when power is applied. This is counteracted with systems such as BMW's Paralever, Moto Guzzi's CARC and Kawasaki's Tetralever.

Marine drive shafts

On a power-driven ship, the drive shaft, or propeller shaft, usually connects the transmission inside the vessel directly to the propeller, passing through a stuffing box or other seal at the point it exits the hull. There is also a thrust block, a bearing to resist the axial force of the propeller. As the rotating propeller pushes the vessel forward, any length of drive shaft between propeller and thrust block is subject to compression, and when going astern to tension. Except for the very smallest of boats, this force isn't taken on the gearbox or engine directly.

Cardan shafts are also often used in marine applications between the transmission and either a propeller gearbox or waterjet.

Drive shafts in Bicycles

.]] The drive shaft has served as an alternative to a chain-drive in bicycles for the past century, although never becoming very popular. A shaft-driven bicycle is described as an "Acatane", from one of their early makers. When used on a bicycle, a drive shaft has several advantages and disadvantages:

Advantages

  • Drive system is less likely to become jammed or broken, a common problem with chain-driven bicycles
  • The use of a gear system creates a smoother and more consistent pedaling motion
  • The rider cannot become dirtied from chain grease or injured by the chain from "Chain bite", which occurs when clothing or even a body part catches between the chain and a sprocket
  • Lower maintenance than a chain system when the drive shaft is enclosed in a tube, the common convention
  • More consistent performance. Dynamic Bicycles claims that a drive shaft bicycle consistently delivers 94% efficiency, whereas a chain-driven bike can deliver anywhere from 75-97% efficiency based on condition.
  • Greater clearance: with the absence of a derailleur or other low-hanging machinery, the bicycle has nearly twice the ground clearance
  • For bicycle rental companies, a drive-shaft bicycle is less prone to be stolen, since the shaft is non-standard, and both noticeable and non-maintainable. This type of bicycle is in use in several major cities of Europe, where there have been large municipal funded, public (and automatic) bicycle rental projects.

Disadvantages

  • A drive shaft system weighs more than a chain system, usually 1-2 pounds heavier
  • At optimum upkeep, a chain delivers greater efficiency
  • Many of the advantages claimed by drive shaft's proponents can be achieved on a chain-driven bicycle, such as covering the chain and gears with a metal or plastic cover
  • Use of lightweight derailleur gears with a high number of ratios is impossible, although hub gears can be used
  • Wheel removal can be complicated in some designs (as it is for some chain-driven bicycles with hub gears).

See also


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