Alps AKS-5/KGF Series
Contents
AKS-5
AKS-5 is a series of reed keyboard switches from Alps Electric. The reed capsule is positioned horizontally across the top of the switch at the back. The end result is a switch that—in the successor design, at least—is slightly too wide to meet the standard 0.75″ (19.05 mm) key spacing. Consequently, the switches are alternated 0°/180° so that the wide part fits into the space left by the narrower section.
AKS-5 is depicted and described in the article Reed-Type Keyboard Switches Offer Inherent Advantages by Tsutomu Osumi, published in JEE, August 1976. The specifications for the switch are not provided, but a lifetime for reed switches of 20 million switch operations is said to be guaranteed.
AKS-5 switches have a special magnet arrangement designed to prevent the contacts re-opening during overtravel.
KGF
Reed switch type KGF was mentioned briefly in the Wizard of ALPS advertisement from Alps Electric USA in 1981. A later advertisement in JEE (Journal of Electronic Engineering) lists the same series, except that KGL is the only reed type listed. It may be that KGF went end-of-life in the early 1980s.
Based on poor-quality scans of Ambit catalogues, it seems almost certain that KGF is the same switch type as AKS-5.
Only one model number is known so far, KGF10021.
Specifications are as follows (per Ambit catalogues and the JEE article):
| Operating force |
60±25 g (KGF10021, Spring 1982 catalogue) 110±20 g (“Non-lock release key”) 200±60 g (“Self-lock key”) |
|---|---|
| Travel | 4.3±0.5 mm |
| Contact resistance | 200 mΩ maximum |
| Rated load | 100 mA at 12 V |
| Lifetime | 20 million cycles |
Successor
A switch type known only as alternating 0°/180° reed switches is the successor to AKS-5. This type replaces the thin plunger of AKS-5 (seemingly sheet metal) with a chunkier plastic plunger, and uses a smaller magnet. Although the revised design is unlikely to be DIN-compliant, it does appear to be shorter in height by maybe 20% or so.
The successor design may have been or become KGL.
Documentation
The material below was scanned by or for WorldRadioHistory.com.