AR PATE
\/ V L oO SPECIFICATION OF KEYBOARD SWITCH KFK type AUG.06.1997 enact 1. Scope : This specification covers MITSUMI keyboard switch KFK series. 2. Electrical Specifications :
2-1, Maximum Rating : D.C. 12V (with pulse width of 200 u sec., duty ratio 1/50), lmA. 2-2. Contact Bounce: 5msec. Max - Initial 1Omsec. Max -:- Over life
(at normal pushing)
-3. Contact Resistance :1.6KQ Max (resistance value of membrane circuit board is included.) 2-4. Insulation Resistance : 50MQ Max (at D.C. 200V) 2-5, Withstand voltage : A.C.250V , 1 minute. 2-6. Circuit : Make Contact , 1 circuit. 3. Mechanical Specifications :
3:1. Force :
(1) Operating Force : 30g typical (0.244.N typicel)
(2) Maximum Force: 50+20g (0440N + 0.196N)
(3) Click Rate : 45+20%
(Decline of Clicking Force after 10 millions operation : within 30%) 3-2. Operating puiut. {,0- 5.5m stroke 3-3. Full Travel : 4.2+0.5mm (at 200g) (at 1.96 N) 3-4. Key Touch Feeling : Keytop must be operated without squeaking , catching , locking with normal pushing. a YT Fah i 00919 |
Ne DRAWING NO. log. e.a\ |Add ST ont UOWATANARE lag vz 7 | Chante Spec, Z2>hAO Sate MITSUMI ELECTRIC CO.,LTD. 4. Endurance Specifications :
4-1. Operating Life : After 10 millions pushing , the switch must be satisfied with electrical and mechanical specifications shown on item 2&3. 41-2. Operating Temperature Range: SC~50C 4-3. Storage Temperature Range : 20C~~-65C (1000H) 4-4. Shock Proof: 20G in 3 Axis 5. Test Condition :
5-1. Measuring Conditions :
Measuring conditions :
Measuring conditions must be at temperature 23+1C humidity 50+2%RH. However the measurement may be conducted under condition of normal temperature
(15~35C) and normal humidity (45~75%RH) unless such conditions affect test results. 5-2.Contact Bounce :
Test shall be made by normal pushing at a speed of 3~5 times per second with D.C 3V, 504 A resistance load. Contact bounce range will be measured at 80% level as shown below. ON f 80% | A:ON Bounce
B: OFF Bounce OFF Sl Time _ Fig. 1. 5-3. Contact Resistance :
Contact resistance included resistance value of membrane circuit board shall be measured at. D.C.24V , 0.1mA (voltage drop method) , applying static load of the keytop. 5-4. Insulation Resistance :
Measure , applying D.C.250V between the terminals. 5-5. Withstand Voltage :
After A.C.250V is applied between the terminals for 1 minute , any change and damage will not be appeared. 5-6. Force :
(1) Operating force :
Measure the operating force when switch makes contact by pushing the center of the keytop.
(2) Maximum Force :
Measure the maximum Force among the full travel except the full travel force.
(3) Minimum Force :
Measure the minimum Force among the travel after the maximum force. Force
(g) A CN 200
(1.46]
Maximum Force Minimum Force Travel(mm) Full Travel Fig.2. MITSUMI ELECTRIC CO.,LTD. 5-7, Operating Point :
Measure the distance when switch makes contact by pushing the center of the keytop. 5-8. Full Travel :
Measure the distance when static load of 200g is to be applied onto the center of the keytop. CHtbN) 5-9. Key touch feeling :
Keytop must be operated , without squeaking , catching , locking with normal pushing of full travel at a speed of 3~~5 times per second. 5-10. Operating Life :
As illustrated in Fig.3 , operating life test shall be made at a speed of 3~7 meter per second pushing the center of the keytop with a plunger of cam life tester. Life test condition D.C.22V if On time : 25mmsec
| Cycle : 3~7 time/sec Pushing force : 200 (4 46N)
(Typical) Polyurethane 00g C1.4bN) _MITSUMI ELECTRIC CO.LTD._ 6. Test Form :
6-1. Humidity Test :
After unit is kept for 96 hours in a chamber of temperature +4022 , and relative humidity 90~95% and then is left in ambient condition for 1 hour , electrical &
mechanical specifications item 2&3 shall be satisfied. 6-2. Low Temperature Test :
After unit is kept for 96 hours in a chamber of temperature -2042C , then is left in ambient condition for 1 hour , electrical & mechanical specifications item 2&3 shall be satisfied. 6-3. High Temperature Test :
After unit is kept for 96 hours in a chamber of temperature +70+2C , then is left in ambient condition for 1 hour , electrical & mechanical specifications item 2&3 shall be satisfied. 6-4, Thermal Shock Test :
After unit is kept for 5 cycles (one cycle consists of -2042C ,]hourand +602C , 1 hour ) and then is left in ambient condition for 1 hour , electrical & mechanical}
specifications item 2&3 shall be satisfied. 6-5. Vibration Proof Test :
Unit shall satisfy electrical & mechanical specifications item 2&3 after the following vibration is applied. Frepuency -10~55 Hz (cycle : 1 minute) Full amplitude : 1.5mm Duration : 2 hours each in 3 directions 6-6. Shock Proof Test :
After 20 G (half-sine wave) is applied to unit 3 times each in 3 directions , electrical &
mechanical specifications item 2&3 shall be satisfied. ef) The test (6-1~6-6) must be done under the open-circuit condition. _ MITSUMI ELECTRIC co.LTD. 7. Appearance of keytop :
7-1. Disposition of keytop :
Disposition of the keytop shall be within the limit of 0.5mm as illustrated in Fig.4 in both vertical and horizontal lines. \
r r Fig. 5. 0.5mm MAX 7-2. Tilt of keytop :
Tilt of keytop shall be within the limit of 0.5mm as illustrated in Fig.5. 0.5mm MAX Fig .6. 7-3, Angular deviation of keytop Angular deviation of keytop shal) be within the limit of 0.5mm as illustrated in Fig 6. 0.5mm MAX MITSUMI ELECTRIC CO.,LTD. 7-4. Uneven level of keytop :
Uneven level of keytop shall be within the limit of 0.5mm as illustrated in Fig.7. However , exclude the bend of the frame.
0.5mm MAX 0214 A MITSUMI ELECTRIC CO.,LTD.