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, 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."
History
1919 Ben P. Ellerbeck conceived a retractable hardtop – a manually operated system on a Hudson coupe that allowed unimpeded use of the rumble seat even with the top down – but never saw production. 1934Lancia introduced the first production, power-operated retractable hardtop in 1934, the Belna Eclipse, designed and patented by Georges Paulin. The Belna was a French-built Lancia Augusta. The French coachbuilder, Marcel Pourtout, custom-built examples of Paulin's designs on other makes like Panhard and Peugeot 401, 402 or 601. 1941Chrysler introduced a retractable hardtop concept car, the Chrysler Thunderbolt. 1953Ford Motor Company spent an estimated US$2 million to engineer a Continental Mark II with a servo-operated retractable roof. The project was headed by Ben Smith, a 30-year-old draftsman. The concept was rejected for cost and marketing reasons. 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 US$18 million more was spent. 1955 Brothers Ed and Jim Gaylord showed their first prototype at the 1955 Paris motor show, but the car failed to reach production. 1957 Ford introduced the Fairlane 500 Skyliner in the United States. A total of 48,394 were built from 1957 to 1959. The retractable top was noted for its complexity and usually decent reliability in the pre-transistor era. Its mechanism contained 10 power relays, 10 limit switches, four lock motors, three drive motors, eight circuit breakers, as well as of electrical wire, and could raise or lower the top in about 40 seconds. The Skyliner was a halo car with little luggage space, and cost twice that of a baseline Ford sedan. 1989Toyota 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. 1995 The Mitsubishi GTO Spyder by ASC was marketed in the U.S. The design was further popularized by such cars as the 1996 Mercedes-Benz SLK. and 2001 Peugeot 206 CC. 2006 Peugeot presented a concept four-door retractable hardtop convertible, the Peugeot 407 Macarena. Produced by French coachbuilding specialist Heuliez, the Macarena's top can be folded in about 30 seconds. It has a reinforcing beam behind the front seats which incorporates LCD screens into the crossmember for the rear passengers.
Construction
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 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.
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 lieu of the standard folding-textile soft-top. Compared to the regular soft-top, the hardtop weighed more yet had no reduction in cargo capacity. 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.
The Chrysler Sebring's retractable hardtop also is marketed alongside a soft-top. According to development engineer Dave Lauzun, during construction, the Karmann-made tops are dropped into a body that is largely identical: both soft-top and retractable feature the same automatic tonneau cover, luggage divider and luggage space. The retractable does feature an underbody cross-brace not included in the softtop.
May enable consolidation/simplification of a manufacturer's car lineup; for instance the BMW Z4 was offered only as a coupé-convertible, compared to the preceding E85 generation that had separate coupé and cabriolet 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.
Potential need for more than minimum clearance while operating the hardtop. For example, the Volvo C70 requires of vertical clearance during operation, the Cadillac XLR requires of vertical clearance and the Mercedes SLK's trunk lid extends rearward while lowering or lifting the top.
