REACTION FORCE GENERATING MEMBER AND KEY SWITCH DEVICE

• US 20200135417A1
• Filed: 12/30/2019
• Published: 04/30/2020
• Est. Priority Date: 03/30/2017
• Status: Active Grant

• Current Assignee: Fujitsu Component Limited (Fujitsu Limited)
• Original Assignee: Fujitsu Component Limited (Fujitsu Limited)
• Inventors: OKUTANI, Shinnosuke
• Granted Patent: US 11,355,293 B2
• Time in Patent Office: Days
• CPC Class Codes: H01H 13/14 Operating parts, e.g. push-button
• CPC Class Codes: H01H 13/20 Driving mechanisms
• CPC Class Codes: H01H 13/705 characterised by construction, mounting or arrangement of operating parts, e.g. push-buttons or keys
• CPC Class Codes: H01H 13/85 characterised by tactile feedback features
• CPC Class Codes: H01H 2215/004 Collapsible dome or bubble
• CPC Class Codes: H01H 2215/006 Only mechanical function
• CPC Class Codes: H01H 2215/02 Reversed domes
• CPC Class Codes: H01H 2217/004 Larger or different actuating area
• CPC Class Codes: H01H 2221/05 Force concentrator; Actuating dimple
• CPC Class Codes: H01H 2227/022 Collapsable dome
• CPC Class Codes: H01H 3/122 with enlarged actuating area, e.g. of the elongated bar-type; Stabilising means therefor

Abstract

A reaction force generating member includes: a first dome that gives a reaction force to an operation member according to the depression of the operation member; and a second dome that includes a hemispherical bowl part disposed inside the first dome, and a projection projecting downward from the center of the bowl part and depressing a switch disposed below the operation member.

Claims

1. A key switch device (100) comprising:

an operation member (10) to be depressed;

a switch (14d) disposed under the operation member; and

a reaction force generating member (15) provided between the operation member and the switch, the reaction force generating member including;

a first dome (15b) that gives a reaction force to the operation member according to the depression of the operation member; and

a second dome (15d) that includes a hemispherical bowl part (15e) disposed inside the first dome, and a projection (15f) projecting downward from the center of the bowl part and depressing a switch (14d) disposed below the operation members, wherein

the first dome (15b) has a first load displacement characteristic in which a depression load of the operation member increases until the first dome (15b) performs buckling deformation according to the depression of the operation member, and the depression load of the operation member decreases after the buckling deformation,

the second dome (15d) has a second load displacement characteristic in which the depression load of the operation member increases according to the depression amount of the operation member,

the projection (15f) contacts the switch (14d) when or after the first dome performs the buckling deformation, and

the projection (15f) turns on the switch (14d) during a period between when a total depression load which is the depression load of the operation member in the total of the first and the second load displacement characteristics of the first dome (15b) and the second dome (15d) decreases, and when the total depression toad reaches a bottom load which is a minimum load after the peak load.