|This article requires additional photographic illustration — keycap mount, black version|
|Inventor||Yasuhiro Tanoue, Mamiko Naka, Kazuhira Izawa, Masayuki Shinohara|
|Total travel||ca. 3 mm|
(also as CN104347295A, CN204011170U, EP2835808A1)
Logitech Romer-G, Omron series B3K, is a tactile mechanical keyboard switch which was revealed with the announcement of the Logitech G910 Orion Spark keyboard in September, 2014.
Romer-G switch is a metal contact keyboard switch from Logitech, developed in partnership with Omron based on a design from Logitech. The "ROMER G" name was trademarked by Logitech International S.A. in an application dated 23rd June 2014. The Omron series name of "B3K" has been found printed onto the side of switches. The Logitech "G" logo is also found on the sides of the switch.
Logitech's specifications on the Romer-G reveal that it is weighted at 45 g, with a high actuation point of 1.5 mm. Cherry MX switches by comparison actuate at around 2 mm. Full travel is alleged to be 3 mm; examination of several switches gave figures between 3.06 and 3.17 mm total travel.
The Romer-G also facilitates LED backlighting via a light pipe leading to a surface-mounted LED. The design is said to focus the light more evenly through the legends on the keycap and minimise light leakage. The patents describe various approaches to achieving the illumination, illustrated with light intensity plots.
The switch is tested to 70 million keystrokes, which makes it one of the highest rated keyboard switches in production. As a light tactile switch, the Romer-G has been compared in feel to the Cherry MX Brown switch by those who have tried it.
The switch provides redundant sensing in an SPST arrangement by using a pair of identical terminals, each bearing a stationary contact and a movable contact. The two lateral ends of each terminals are at 90° to each other, and collectively the terminals occupy all four sides within the switch, with the movable contact at one end of each terminal meeting the stationary contact at the opposite end of the other terminal. The slider has four corner posts, and two of these each hold one pair of contacts apart. Tactility is achieved by a ramp at the tip of these posts.
The slider is supported by a large spring, which sits around the centre light guide.
The switch is both upstroke and downstroke damped, using a pair of what the patents call an "elastic touch piece". These are lateral prongs projected from the slider, that collide with the base (downstroke) and lid (upstroke) and absorb the impact. Specifically, the prong hits a raised area in the base on the way down, and ridges in the lid on the way up. The patent describes the product as a "silent type switch having small operation sound and return sound".
The patent depicts the tactile "pressing rib" design but does not explain the shape or mention tactility.
- NAG Online — Logitech announces the G910 Orion gaming keyboard | NAG Online Dated 2014-09-17. Retrieved 2015-08-01.
- inovia.com — inovia | U.S. trademark search and registration Retrieved 2015-08-01.
- Logitech — Romer-G Retrieved 2015-08-01.
- Deskthority — [Reviews] Logitech G910 Orion Spark Posted 2014-11-25. Retrieved 2015-08-01.
- Geekhack — Logitech G910 Orion Spark - mini review Posted 2014-10-31. Retrieved 2015-08-01.