Multifunction key and electronic device with multifunction key

Patent metadata

Field	Value
Publication number	US-9673000-B2
Application number	US-201514755082-A
Country	US
Kind code	B2
Filing date	Jun 30, 2015
Priority date	Mar 26, 2015
Publication date	Jun 6, 2017
Grant date	Jun 6, 2017

Abstract

A multifunction key includes a key member, a conductive member, and a circuit baseboard. A portion of the key member extends out from a shell of an electronic device; the conductive member is fixed on a bottom of the key member. The conductive member includes a first protrusion member and a second protrusion member. One surface of the circuit baseboard includes a conductive layer and a resistance layer respectively contacting the first and the second protrusion member. Another surface of the circuit baseboard includes a first and second conductive terminal respectively connected to the conductive layer and the resistance layer. The conductive layer, resistance layer, first and second conductive terminal, conductive member, and an internal circuit of the electronic device form a circuit loop. When the key member moves, a resistance value of the resistance layer within in the circuit loop is changed and produces a corresponding key command.

First claim

What is claimed is:

1. A multifunction key comprising:
a key member, wherein, a portion of the key member is to be exposed on an outside of a shell of an electronic device;
a conductive member fixed on a bottom of the key member, wherein the conductive member comprises a first protrusion member and a second protrusion member extending toward a direction away from the bottom of the key member;
a circuit baseboard comprising a first surface and a second surface opposite to the first surface, wherein, the first surface comprises a first conductive layer and a resistance layer which are isolated with each other, the first surface faces the conductive member, the first conductive layer and the resistance layer are respectively electrically connected to the first protrusion member and the second protrusion member; the second surface comprises a first conductive terminal and a second conductive terminal, a first end of the first conductive terminal is electrically connected to the conductive layer via a first conductive hole passing through the circuit baseboard, a first end of the second conductive terminal is electrically connected to the resistance layer via a second conductive hole passing through the circuit baseboard, a second end of the first conductive terminal and a second end of the second conductive terminal are to be electrically connected to an internal circuit of the electronic device;
wherein, the conductive layer, and the resistance layer are configured to form a circuit loop with the internal circuit of the electronic device via the first conductive terminal, the second conductive terminal, the first conductive hole, the second conductive hole, and the conductive member; when the key member moves along a direction of arrangement of the conductive layer and the resistance layer, a distance between the second protrusion member and the second conductive hole is changed, a length of the resistance layer between the second protrusion member and the second conductive hole is changed too, and the resistance value of the resistance layer within the circuit loop is changed too, thus to cause the internal circuit of the electronic device to produce different key commands corresponding to different resistance values of the resistance layer within the circuit loop.

2. The multifunction key according to claim 1 , wherein the conductive layer, the first conductive terminal, the second conductive terminal, the first conductive hole, the second conductive hole, and the conductive member are all made of materials with high conductivity, the resistance layer is made of materials with low conductivity, the circuit baseboard is made of insulating material, and the resistance value of the resistance layer within the circuit loop is substantially the same as a resistance value of the circuit loop.

3. The multifunction key according to claim 2 , wherein the conductive layer is a first coating coated on a substantially half area of the first surface of the circuit baseboard, and the resistance layer is a second coating coated on another substantially half area of the first surface of the circuit baseboard, and a portion of the first surface between the conductive layer and the resistance layer is not coated the conductive layer and the resistance layer.

4. The multifunction key according to claim 2 , further comprising a cover member, wherein the cover member is fixed on the second surface of the circuit baseboard, and is further extended to an inner surface of the sidewall and fixed on the inner surface of the sidewall, thus to limit the key in the sidewall.

5. The multifunction key according to claim 4 , wherein positions of the cover member corresponding to the second end of the first conductive terminal and the second end of the second conductive terminal respectively set one opening hole, the second end of the first conductive terminal and the second end of the second conductive terminal are connected to the internal circuit via the opening holes.

6. An electronic device comprising:
a power supply and detection unit;
a processor connected to the power supply and detection unit;
a shell; and
a multifunction key setting on a sidewall of the shell, the multifunction key comprising:
a key member, wherein a portion of the key member is exposed on an outside of the shell;
a conductive member fixed on a bottom of the key member, wherein the conductive member comprises a first protrusion member and a second protrusion member extending toward a direction away from the bottom of the key member;
a circuit baseboard comprising a first surface and a second surface opposite to the first surface, wherein, the first surface comprises a first conductive layer and a resistance layer which are isolated with each other, the first surface faces the conductive member, the first conductive layer and the resistance layer are respectively electrically contacted to the first protrusion member and the second protrusion member; the second surface comprises a first conductive terminal and a second conductive terminal, a first end of the first conductive terminal is electrically connected to the conductive layer via a first conductive hole passing through the circuit baseboard, a first end of the second conductive terminal is electrically connected to the resistance layer via a second conductive hole passing through the circuit baseboard, a second end of the first conductive terminal and a second end of the second conductive terminal are electrically connected to the power supply and detection unit;
wherein, the conductive layer, and the resistance layer, and the power supply and detection unit form a circuit loop via the first conductive terminal, the second conductive terminal, the first conductive hole, the second conductive hole, and the conductive member; when the key member moves along a direction of arrangement of the conductive layer and the resistance layer, a distance between the second protrusion member and the second conductive hole is changed, a length of the resistance layer between the second protrusion member and the second conductive hole is changed too, and the resistance value of the resistance layer within the circuit loop is changed too;
wherein, the power supply and detection unit is configured to provide a predetermined voltage to the circuit loop and detect a current value of the circuit loop;
the processor is configured to calculate the resistance value according to the predetermined voltage and the detected current value, determine a key command corresponding to the resistance value, and execute the corresponding key command.

7. The electronic device according to claim 6 , wherein the conductive layer, the first conductive terminal, the second conductive terminal, the first conductive hole, the second conductive hole, and the conductive member are all made of materials with high conductivity, the resistance layer is made of materials with low conductivity, the circuit baseboard is made of insulating material, and the resistance value of the resistance layer within the circuit loop is substantially the same as a resistance value of the circuit loop.

8. The electronic device according to claim 7 , wherein the processor determines a resistance value range that the resistance value of the circuit loop within, and determines the key command corresponding to the determined resistance value range, according to a resistance value range and key command relationship table; the resistance value range and key command relationship table records relationships between a plurality of resistance value ranges and a plurality of key commands, when the resistance value is less than a first predetermined resistance value, the corresponding key command is a first key command, when the resistance

Assignees

• Shenzhen Futaihong Prec Ind Co
• Fih Hong Kong Ltd

Inventors

• Liu Su-Tzong
• Liu sheng-ying
• Xiao wei-rong

Classifications

• H01H15/005

  adapted for connection with printed circuit boards · CPC title

• H01H15/10 Primary

  Operating parts · CPC title

• H01H3/0213

  Combined operation of electric switch and variable impedance, e.g. resistor, capacitor (H01H9/061 takes precedence) · CPC title

• H03K17/9625

  using a force resistance transducer · CPC title

• H03K17/965

  Switches controlled by moving an element forming part of the switch · CPC title