Engineering:Retractable hardtop

From HandWiki
Short description: Vehicle with a retracting solid roof


A Volvo C70 with retractable hardtop

A retractable hardtop — also known as "coupé convertible" or "coupé cabriolet" — is a car with an automatically operated, self-storing hardtop, as opposed to the folding textile-based roof used by traditional convertible cars.

The benefits of improved climate control and security are traded off against increased mechanical complexity, cost, weight, and often reduced luggage capacity.

A 2006 New York Times article suggested the retractable hardtop may herald the demise of the textile-roofed convertible,[1] and a 2007 Wall Street Journal article suggested "more and more convertibles are eschewing soft cloth tops in favor of sophisticated folding metal roofs, making them practical in all climates, year-round."[2]

History

1934 Peugeot 401D Coupé transformable Eclipse (Pourtout)
1934 Peugeot 601 C Eclipse
1934 Lancia Belna Eclipse

1922 Ben P. Ellerbeck was granted a patent (U.S. No. 1,379,906 on 31 May 1921) for a retractable hardtop roof design for cars.[3] He developed several scale models for the 1922 Automobile Body Builders Exhibition in New York City.[4] In 1922, he modified a 1919 Hudson Super Six roadster with his manually operated gear and spring "flip top" system.[3] It allowed unimpeded use of the rumble seat even with the top down.[5] The design was not put into production.[6]

1931 Georges Paulin made his idea public by applying for a patent on a detachable hard roof design, that could ultimately be moved and stowed automatically in a car's rear luggage compartment, under a reverse-hinged rear-deck lid.[7]

1932 The French patent system granted Paulin patent number 733.380 for his Eclipse roof system, on July 5, 1932.[7]

1934 Paulin's Eclipse retractable hard roof [1] was first presented on the Peugeot 401D Éclipse Décapotable, a low convertible coupé.[8][9] In 1933, Paulin showed his designs to premier coachbuilder Marcel Pourtout, who hired him as lead designer, and in 1934 they equipped first a Peugeot 401D, followed by a 601C, with "Eclipse" roofs and bodywork, on chassis provided by Emile Darl'mat. In the same year, a Lancia Belna, a French-built Lancia Augusta, was also built as an Eclipse.[10]

1935 Peugeot purchased Paulin's patent, and introduced the first factory production, power-operated, retractable hardtop in 1935, the "402BL Éclipse Décapotable",[11][12] of which some 470 were built.[1] Pourtout kept building custom examples, designed by Paulin, on other makes like Delage and Panhard, and "Eclipse" coupé-convertibles based on the Peugeot 301, 401, 601, 302, and 402.[1]

1941 Chrysler introduced a retractable hardtop concept car, the Chrysler Thunderbolt.[13][14]

1947 American Playboy Automobile Company marketed one of the first series produced convertibles, with a retractable roof consisting of more than one section. Ninety-seven production models were made, until their bankruptcy in 1951.[15]

Playboy with convertible hard-top – Amsterdam International Autoshow (AutoRAI), 1948
Photographs show the Playboy with the top in a closed and open configuration.
1958 Ford Fairlane 500 Skyliner with roof in mid folding action

1953 Ford Motor Company spent an estimated United States dollar 2 million (US$19,111,940 in 2019 dollars[16]) to engineer a Continental Mark II with a servo-operated retractable roof. The project was headed by Ben Smith, a 30-year-old draftsman.[17][failed verification] The concept was rejected for cost and marketing reasons.[5] Engineering work was recycled to the Ford Division which used the retractable mechanism in their 1957-1959 flagship Ford Fairlane 500 Skyliner after an estimated United States dollar 18 million (US$163,855,450 in 2019 dollars[16]) more was spent.[18]

1955 Brothers Ed and Jim Gaylord showed their prototype at the 1955 Paris Motor Show, but the car failed to reach production.[19]

1956 After working for 4,000 hours and investing $100 in the whole car, Raymond P. Meyette, built a one-piece power-operated hardtop convertible using a 1952 Nash Ambassador chassis.[20]

1957 Ford introduced the Fairlane 500 Skyliner in the United States. A total of 48,394 were built from 1957 to 1959.[5] The retractable top was noted for its complexity and usually decent reliability[21][22] in the pre-transistor era. Its mechanism contained ten power relays, ten limit switches, four lock motors, three drive motors, eight circuit breakers, as well as 610 feet (190 m) of electrical wire,[5]. It could raise or lower the top in about 40 seconds. The Skyliner was a halo car with little luggage space (i.e., practicality), and cost twice that of a baseline Ford sedan.

1989 Toyota introduced a modern retractable hardtop, the MZ20 Soarer Aerocabin. The car featured an electric folding hardtop and was marketed as a 2-seater with a cargo area behind the front seats. Production was 500 units.

1996 Mercedes SLK

1995 The Mitsubishi GTO Spyder by ASC was marketed in the U.S.[6] The design was further popularized by such cars as the 1996 Mercedes-Benz SLK.[1] and 2001 Peugeot 206 CC.

2006 Peugeot presented a concept four-door retractable hardtop convertible, the Peugeot 407 Macarena.[23] Produced by French coachbuilding specialist Heuliez, the Macarena's top can be folded in about 30 seconds.[23] It has a reinforcing beam behind the front seats which incorporates LCD screens into the crossmember for the rear passengers.[23]

Construction

Closing of the retractable hardtop of a BMW 3-series (E93)

Retractable hardtops are commonly made from between two and five sections of metal or plastic and often rely on complex dual-hinged trunk/boot lids that enable the trunk lid to both receive the retracting top from the front and also receive parcels or luggage from the rear. The trunk also often includes a divider mechanism to prevent the loading of luggage that would conflict with the operation of the hardtop.

Variations

  • The Volkswagen Eos features a five-segment retractable roof where one section is itself an independently sliding transparent sunroof.[2]
  • The Mercedes SL hardtop features a glass section that rotates during retraction to provide a more compact "stack."
  • The third-generation Mazda MX-5 was available with an optional power retractable hardtop, in place of the standard folding-textile soft-top. Compared to the regular soft-top, the hardtop weighed 77 lb (35 kg) more yet had no reduction in cargo capacity.[24] The MX-5 was one of the few cars offering both hardtop and soft-top convertible choices. The hardtop roof was constructed of polycarbonate and manufactured by the German firm Webasto.[25]
  • The Chrysler Sebring's (and its successor the Chrysler 200's) retractable hardtop also is marketed alongside a soft-top. According to development engineer Dave Lauzun, during construction, the Karmann-made tops are installed into a largely identical body: both soft-top and retractable feature the same automatic tonneau cover, luggage divider, and luggage space.[26] The retractable does feature an underbody cross-brace not included in the softtop.

Comparison with soft tops

The retractable hardtop's advantages include:

  • More weatherly when the roof is raised
  • More secure than fabric tops[2][27]
  • Increased structural rigidity
  • May enable consolidation/simplification of a manufacturer's car lineup; for instance the BMW Z4 (E89) was offered only as a coupé-convertible (hardtop), compared to the preceding E85 generation that had separate coupé and cabriolet (soft-top) variants.

The retractable hardtop's disadvantages include:

  • Higher initial cost
  • Increased mechanical complexity
  • Potentially diminished passenger and trunk space compared to a soft-top convertible.[28][29]
  • Higher weight and center of gravity than soft-top convertibles, potentially reducing handling.[30][28][29]
  • Potential need for more than minimum clearance while operating the hardtop. For example, the Volvo C70 requires 6.5 feet (2 m) of vertical clearance during operation,[31] the Cadillac XLR requires 6 ft 10 12 in (2 m) of vertical clearance and the Mercedes SLK's trunk lid extends rearward while lowering or lifting the top.

List of retractable hardtop models

Gallery

References

  1. 1.0 1.1 1.2 1.3 1.4 Sass, Rob (10 December 2006). "New Again: The Hideaway Hardtop". The New York Times. https://www.nytimes.com/2006/12/10/automobiles/10RETRACT.html?ex=1323406800&en=a440f0f4ff67f836&ei=5090&partner=rssuserland&emc=rss. 
  2. 2.0 2.1 2.2 Vella, Matt (26 April 2007). "Convertibles with Hard Tops". The Wall Street Journal. https://www.wsj.com/articles/SB117753756980082567. 
  3. 3.0 3.1 Gosden, W.E. (April 1979). "The first Fliptop? Ellerbeck had a Better Idea". Special Interest Autos: 20-21. 
  4. Creager, Reid (February 2022). "Going Like 100: the convertible celebrates a milestone birthday, all started by an uncelebrated inventor". Inventors Digest 38 (2): 14-16. https://www.inventorsdigest.com/wp-content/uploads/2022/03/INV-vol-38-02-February-2022Final.pdf. Retrieved 14 January 2024. 
  5. 5.0 5.1 5.2 5.3 Nerad, Jack. "Ford Skyliner". Driving Today. http://www.drivingtoday.com/greatest_cars/ford_skyliner/index.html. 
  6. 6.0 6.1 "History, Revival". Retractable Hardtop Online. http://retractable.free.fr/uk/index.html. 
  7. 7.0 7.1 Buchanan, James. "The Story of Lancia, Paulin and John Moir". http://www.redroom.com/articlestory/the-story-lancia-paulin-and-john-moir. 
  8. Brierley, Brooks T. (17 June 2001). "1935 Peugeot Model 401D Eclipse: The first retractable hardtop". https://www.autoweek.com/news/a2119691/1935-peugeot-model-401d-eclipse-first-retractable-hardtop/. Retrieved 31 March 2021. 
  9. "From the Zero to the Eclipse". http://peugeot.mainspot.net/hist11.shtml. 
  10. "1934 Lancia Belna Eclipse by Pourtout". https://rmsothebys.com/en/auctions/pa15/paris/lots/r105-1934-lancia-belna-eclipse-by-pourtout/181559. 
  11. "Disappearing Top On Auto Worked By Push Button". Popular Mechanics 63 (2): 253. February 1935. https://books.google.com/books?id=yN8DAAAAMBAJ&q=Popular+Science+1935+plane+%22Popular+Mechanics%22&pg=PA253. Retrieved 14 August 2013. 
  12. "Latest Foreign Auto Has Disappearing Top". Popular Mechanics 65 (1): 53. January 1936. https://books.google.com/books?id=QdsDAAAAMBAJ&pg=RA1-PA43. Retrieved 14 August 2013. 
  13. ((Auto Editors of Consumer Guide)) (29 November 2007). "1941 Chrysler Thunderbolt Roadster". https://auto.howstuffworks.com/1941-chrysler-thunderbolt-roadster.htm. 
  14. "Vanderbilt Cup Races - Blog - Mystery Friday Foto #4 Solved: The 1941 Chrysler Thunderbolt concept car with links to Tucker 1044 and 1937 Chrysler’s Chrysler". 30 January 2023. https://www.vanderbiltcupraces.com/blog/article/mystery_friday_foto_4_an_early_concept_car. 
  15. Radu, Vlad (6 June 2022). "Remembering the Playboy, America's First Production Convertible With a Retractable Hardtop". autoevolution. https://www.autoevolution.com/news/remembering-the-playboy-america-s-first-production-convertible-with-a-retractable-hardtop-190494.html. 
  16. 16.0 16.1 Federal Reserve Bank of Minneapolis. "Consumer Price Index (estimate) 1800–". https://www.minneapolisfed.org/about-us/monetary-policy/inflation-calculator/consumer-price-index-1800-. 
  17. Merlis, Bob (6 March 2007). "Lucy Loved Ford's First Hard Top Convertible". http://www.greatcarstv.com/index2.php?option=com_content&do_pdf=1&id=87. 
  18. Severson, Aaron (26 April 2009). "Raising the Roof: The Ford Skyliner 'Retrac'". Ate Up With Motor. http://ateupwithmotor.com/model-histories/ford-skyliner/. 
  19. ((Auto Editors of Consumer Guide)) (13 November 2007). "1950 Gaylord concept cars". http://auto.howstuffworks.com/1950s-gaylord-concept-cars.htm. 
  20. Sand, George X. (December 1956). "They told him it could not be built - so he built it himself: A Hardtop Convertible". Popular Mechanics 106 (6): 138-139. https://books.google.com/books?id=q-EDAAAAMBAJ&pg=PA138&lpg=PA138&dq=Popular+Mechanics+after+four+years+of+trial+and+error+Raymond+P.+Meyette+hardtop+convertible. Retrieved 13 January 2024. 
  21. Willson, Quentin (1995). The Ultimate Classic Car Book. DK Publishing. ISBN 0-7894-0159-2. https://archive.org/details/ultimateclassicc00quen. 
  22. ((Auto Editors of Consumer Guide)) (20 July 2007). "1957-1959 Ford Fairlane 500 Skyliner". http://auto.howstuffworks.com/1957-1959-ford-fairlane-skyliner.htm/printable. 
  23. 23.0 23.1 23.2 "¡Hey, Macarena! Heuliez Creates an Open-Top Peugeot 407". Edmunds. 28 January 2006. http://www.edmunds.com/insideline/do/News/articleId=109085. 
  24. 24.0 24.1 Vaughn, Mark (10 September 2006). "2007 Mazda MX-5 Miata Power Retractable Hardtop". http://www.autoweek.com/apps/pbcs.dll/article?AID=/20061009/FREE/61003001/1004. 
  25. "2007 Mazda MX-5 Miata Hardtop". Car and Driver. 1 September 2006. https://www.caranddriver.com/news/2007-mazda-mx-5-miata-hardtop-car-news. 
  26. Lauzun, Dave. "2008 Chrysler Sebring Convertible". https://www.youtube.com/watch?v=jiIEyCFR9Gg. 
  27. "Great Drive: Luxury Hardtop Convertible Comparison". Automobile. August 2009. http://www.automobilemag.com/features/great_drives/0908_luxury_hardtop_convertible_comparison/index.html. Retrieved 14 August 2013. 
  28. 28.0 28.1 St. Antoine, Arthur (May 2010). "Luxury Convertible Comparison: 2010 Audi A5 vs 2010 BMW 335i vs 2009 Infiniti G37 vs 2010 Lexus IS 350". Motor Trend. http://www.motortrend.com/roadtests/convertibles/112_1005_luxury_convertible_comparison/. Retrieved 3 February 2014. 
  29. 29.0 29.1 Swan, Tony (June 2007). "2007 VW Eos vs. Audi A4, BMW 328i, Volvo C70, Saab 9-3 – Comparison Tests". http://www.caranddriver.com/comparisons/2007-vw-eos-vs-audi-a4-bmw-328i-volvo-c70-saab-9-3-comparison-tests. 
  30. Swan, Tony (March 2010). "2010 Audi A5 2.0T Quattro vs. 2010 BMW 328i, 2009 Infiniti G37, 2010 Lexus IS350C – Comparison Tests". Car and Driver. http://www.caranddriver.com/reviews/comparisons/10q1/2010_audi_a5_2.0t_quattro_vs._2010_bmw_328i_2009_infiniti_g37_2010_lexus_is350c-comparison_tests. Retrieved 3 February 2014. 
  31. "2007 Volvo C70". http://new.volvocars.com/ownersdocs/2007/2007_C70/07c70_04.htm. 
  32. Keebler, Jack (August 2002). "2004 Cadillac XLR". Motor Trend. http://www.motortrend.com/roadtests/112_0208_cadxlr. Retrieved 6 March 2011.