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.

Improved climate control and security benefits are traded against increased mechanical complexity, cost, weight, and often reduced luggage capacity.

A 2006 New York Times article suggested the retractable hardtop might 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]

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 5 July 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. 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 build custom examples, designed by Paulin, on other makes including Delage and Panhard as well as the "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 the company's bankruptcy in 1951.^[15]

The 1948 Playboy car with its top in a closed and open configuration

1953 Ford Motor Company spent an estimated US$2 million (US$22,776,119 in 2023 dollars^[16]) to engineer a Continental Mark II with a servo-operated retractable roof. The concept was rejected for cost and marketing reasons.^[5] Engineering work was used by Ford for the retractable mechanism in their 1957 through 1959 flagship Ford Fairlane 500 Skyliner.

1955 Brothers Ed and Jim Gaylord showed a prototype at the 1955 Paris Motor Show, but the car failed to reach production.^[17]

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.^[18]

1957 Ford introduced the Fairlane 500 Skyliner in the United States. Further development of the 1953 Continental Mark II retractable proposal cost an estimated US$18 million (US$195,270,142 in 2023 dollars^[16]).^[19] The Skyliner was a halo car with little luggage space and was priced double the baseline Ford sedan. A total of 48,394 were built from 1957 until 1959.^[5] 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 retractable top was noted for its complexity and usual reliability in the pre-transistor era.^[20][21]

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

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.^[22] Produced by French coachbuilding specialist Heuliez, the Macarena's top folded in about 30 seconds.^[22] It has a reinforcing beam behind the front seats incorporating LCD screens into the crossmember for the rear passengers.^[22]

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.

• The Volkswagen Eos features a five-segment retractable roof where one section is 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. It did not reduce cargo capacity.^[23] The hardtop roof was polycarbonate and manufactured by the German firm Webasto.^[24]
• The retractable hardtop used on the Chrysler Sebring (and its successor the Chrysler 200) was marketed alongside a soft-top. According to development engineer Dave Lauzun, the Karmann-made tops were installed into identical body designs and used the same automatic tonneau cover, luggage divider, and luggage space.^[25] The retractable version featured an underbody cross-brace not included in the softtop.

The retractable hardtop's advantages include:

• More weatherly when the roof is raised
• More secure than fabric tops^[2][26]
• Increased structural rigidity
• May enable consolidation/simplification of a manufacturer's car lineup; for example, 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.^[27][28]
• Higher weight and center of gravity than soft-top convertibles, potentially reducing handling.^[29][27][28]
• 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,^[30] the Cadillac XLR requires 6 ft 10+1⁄2 in (2 m) of vertical clearance and the Mercedes SLK's trunk lid extends rearward while lowering or lifting the top.

• 
  Mazda Miata Power Retractable Hard Top (PRHT) c. 2007, with polycarbonate hardtop^[23]
• 
  Cadillac XLR c. 2007, aluminum hardtop made by a joint venture of Mercedes-Benz and Porsche^[31]
• 
  Daihatsu Copen c. 2001, a retractable hardtop in the Japanese Kei class
• 
  Ford Focus CC c. 2006, its retractable hardtop final assembly by Pininfarina
• 
  Chevrolet SSR c. 2004, pickup truck retractable hardtop engineered by ASC
• 
  Volkswagen Eos c. 2007, the five-segment top includes a sliding sunroof made by OASys
• 
  Opel Astra Twintop (2005-2012), three-part roof stores in the upper half of the boot for luggage space below it