Seiko “Prospex:” The Origin of Today’s Automatic Chronographs
Vertical Clutch and Automatic Winding
Three automatic chronograph watches were released in 1969. Without a doubt, the one with the most lasting impact was the Seiko Caliber 6139. The combination of the compact automatic winding mechanism with a vertical clutch for more precise stopwatch measurement and a column wheel, which became widespread among high-end chronograph watches, is still favored by many watchmakers today.
Continuing this tradition today are two automatic chronographs announced in 2019. Both the
Seiko Automatic Chronograph 50th Anniversary Limited Edition and the Seiko Chronograph 55th Anniversary Limited Edition incorporate the automatic chronograph Caliber 8R48 movement made by Seiko Instruments. This movement mounts a chronograph module with vertical clutch on the front dial of the automatic winding 6R Series with Magic Lever.
Seiko Prospex Automatic Chronograph 50th Anniversary Limited Edition SRQ029: An Automatic Chronograph 50th Anniversary Limited Edition based on the Caliber 6138 two-counter chronograph with 12-hour counter. Befitting a premium watch is the sapphire crystal, with a highly three-dimensional box shape. Automatic winding (Caliber 8R48). 34 jewels. 28,800 vibrations per hour. Power reserve approximately 45 hours. SS (diameter 41 mm, thickness 16 mm). Water resistance 10 bar. Limited editions of 1,000 watches worldwide. US$3,600. To be released December 7, 2019
61 Chronograph: The design motif for the model “Prospex” is the so-called “Panda,” released in 1970. The narrow bezel design and thin hands and indexes led the way for 1970s design trends. Automatic winding (Caliber 6138B, movement diameter 27.4 mm, thickness 7.9 mm). 23 jewels. 21,600 vibrations per hour. (Seiko Museum collection)
Crown Chronograph: Seiko’s first wristwatch chronograph, released in 1964. It was designed by Toshihiko Ohki of Suwa Seikosha. He completed the work referring only to written materials. It was an orthodox design with a carrying-arm horizontal clutch and column wheel. Hand-winding (Caliber 5719A, movement diameter 27.6 mm, thickness 6.1 mm). 21 jewels. 18,000 vibrations per hour. SS. (Seiko Museum collection)
Seiko Presage Seiko Chronograph 55th Anniversary Limited Edition SRQ031: An homage to the Crown Chronograph. The basic structure is the same as the SRQ029. The Zaratsu polish is applied to the lug upper surface is also the same. As with the Crown Chronograph, however, it adopts a box-shaped crystal and the hair line finish on the dial are emphasized. Automatic winding (Caliber 8R48). 34 jewels. 28,800 vibrations per hour. Power reserve approximately 45 hours. SS (diameter 42.3 mm, thickness 15.3 mm). Water resistance 10 bar. Limited editions of 1,000 watches worldwide. US$3,300. To be released December 7, 2019
Follow this link for a comprehensive look at Seiko’s chronograph history.