RAFI RS 76 M
 | |
| Manufacturer | RAFI |
|---|---|
| Family | RAFI full-travel key switch |
| Introduced | 1975 |
| Switch type | Linear; progressive rate; latching action |
| Sense method | Metal contact |
| Bounce time |
5 ms 10 ms (illuminated) |
| Total travel | 4 mm |
| Keycap mount | RAFI mount |
| Switch mount | PCB mount |
RAFI RS 76 M is a series of metal contact switches in the RAFI full-travel key switch family. It is the mechanical counterpart to the Hall effect RS 76 C, and the 4 mm travel equivalent to RS 74 M. The series comprises standard, illuminated and latching action switches, with linear and progressive rate feel depending on design.
Design[edit | edit source]
All RS 76 M switches are open top; the diode versions do use a switch top but it leaves most of the internals exposed regardless.
The non-illuminated switches are crosspoint contact. The perimeter loop movable contact used in this design leaves no room for internal LEDs, so the illuminated versions of the switch instead use a "bridge" contact: this comprises a horizontal flat metal bar that is lowered by the slider onto a pair of stationary contacts, one on either side of the switch. To allow for overtravel, this bar sits below a spring, and once it reaches the stationary contacts the slider continues to move, with the spring above the bar being compressed. This gives the switch a progressive rate force curve, and the change in force is sharp enough that keys can be tapped light enough to actuate.
Variants[edit | edit source]
The RAFI Electromechanical Components 2001 catalogue provided part numbers for IP 40 and IP 65–rated switches; at present, only IP 40–rated switches are listed in RAFI catalogues. The separate part numbers for different LED colours are also no longer listed.
The series appears to be divided as follows:
- 3.13.002.nnnn — IP40
- 3.13.012.nnnn — IP65
- 3.13.005.nnnn — with diode
| Sub-series | Action | IP rating | Terminal force | Part number | |
|---|---|---|---|---|---|
 |
RAFI RS 76 M (basic) | Momentary | IP 40 | 90 cN | 3.13.002.502/0000 (2016) 3.13002.502 (2001) |
 |
RAFI RS 76 M (basic) | Momentary | IP 40 | 140 cN | 3.13.002.512/0000 (2016) 3.13002.512 (2001) |
| File:No photograph.svg | RAFI RS 76 M (basic) | Momentary | IP 65 | 110 cN | 3.13012.502 (2001) |
| File:No photograph.svg | RAFI RS 76 M (basic) | Momentary | IP 65 | 160 cN | 3.13012.512 (2001) |
 |
RAFI RS 76 M (diode) | Momentary | IP 40 | 90 cN | 3.13.005.001/0000 (2016) 3.13005.001 (2001) |
 |
RAFI RS 76 M (diode) | Momentary | IP 40 | 140 cN | 3.13.005.011/0000 (2016) 3.13005.011 (2001) |
| File:No photograph.svg | RAFI RS 76 M (diode) | Momentary | IP 65 | 110 cN | 3.13012.001 (2001) |
| File:No photograph.svg | RAFI RS 76 M (diode) | Momentary | IP 65 | 160 cN | 3.13012.011 (2001) |
 |
RAFI RS 76 M (illuminated) | Momentary | IP 40 | 100 cN | 3.13.002.102/0000 (2016) 3.13002.102/0000 (2001) |
| File:No photograph.svg | RAFI RS 76 M (illuminated) | Momentary | IP 40 | 140 cN | 3.13.002.107/0000 (2001) |
 |
RAFI RS 76 M (illuminated) | Latching | IP 40 | 100 cN | 3.13.002.022/0000(2016) 3.13002.022/0000(2001) |
 |
RAFI RS 76 MX | Momentary | IP 40 | 100 cN | 3.13.002.922/0000 (2016) |
The RAFI Electromechanical Components 2001 catalogue also lists the following dedicated part numbers for the illuminated versions with LEDs fitted:
| Action | Terminal force | LED colour | Part number |
|---|---|---|---|
| Momentary | 100 cN | Red | 3.13002.102/1350 |
| Momentary | 100 cN | Yellow | 3.13002.102/1450 |
| Momentary | 100 cN | Green | 3.13002.102/1550 |
| Momentary | 140 cN | Red | 3.13002.107/1350 |
| Momentary | 140 cN | Yellow | 3.13002.107/1450 |
| Momentary | 140 cN | Green | 3.13002.107/1550 |
| Latching | 100 cN | Red | 3.13002.022/1350 |
| Latching | 100 cN | Yellow | 3.13002.022/1450 |
| Latching | 100 cN | Green | 3.13002.022/1550 |
