1. Technical Field
The present disclosure relates to data input devices, and particularly to a data input device with a heating function.
2. Description of the Related Art
Data input devices such as a mouse and a stylus are commonly used with computers. However, it is uncomfortable for people to use such input devices for a long time in a cold environment.
Referring to
The heating circuit 200 includes a switch S, a direct current (DC) relay K, and an electric heater EH. One end of the switch S, functioning as a first terminal of the heating circuit 200, is connected the 5V power line VCC. The other end of the switch S is connected to one end of the DC relay K and, functioning as a second terminal of the heating circuit 200, is also connected to the temperature control circuit 300. The other end of the DC relay K is connected to the ground line GND via the electric heater EH.
The temperature control circuit 300 includes a diode D1, a variable resistor RP, a electronic switch Q1, a resistor R1, and a diode D2. A cathode of the diode D1, functioning as a first terminal of the temperature control circuit 300, is connected to the second terminal of the heating circuit 300 and also connected to a power pin 1 of the electronic switch Q1. An anode of the diode D1 is connected to one fixed end of the variable resistor RP. The other fixed end of the variable resistor RP is connected to the ground line GND. A sliding end of the variable resistor RP is connected to a control pin 5 of the electronic switch Q1. Two input/output (I/O) pins 2, 3 of the electronic switch Q1 are connected to the ground line GND via the resistor R1. A ground pin 4 of the electronic switch Q1 is connected to the ground line GND. A cathode of the diode D2 is connected to the I/O pin 2 of the electronic switch Q1. An anode of the diode D2 is grounded. The I/O pin 2 of the electronic switch Q1, functioning as a second terminal of the temperature control circuit 300, is also connected to the indication circuit 400.
The indication circuit 400 includes a resistor R2 and a light-emitting diode (LED) D3. The anode of the LED D3 is connected to the second terminal of the temperature control circuit 300 via the resistor R2. The cathode of the LED D3 is connected to the ground line GND.
In one embodiment, the diode D1 is a germanium diode, and the diode D2 is a silicon rectifier diode. The electronic switch Q1 is a TWH877 integrated circuit (IC) chip, in one embodiment. Users can determine the temperature of the data input device 10 by regulating the variable resistor RP.
When it is desired to heat the data input device, the switch S is closed to connect the DC relay K to the 5V power line VCC. When the temperature of the data input device 10 is low, a reverse resistance of the diode D1 will be high such the voltage at a control pin 5 of the electronic switch Q1 will be lower than the bias voltage of the electronic switch Q1, thus the electronic switch Q1 is off. The bias voltage required for the electronic switch Q1 is controlled by setting of the variable resistor RP. The DC relay K is closed to activate the electronic heater EH. The reverse resistance of the diode D1 reduces as the temperature of the data input device 10 increases, thereby the voltage at the control pin 5 of the electronic switch Q1 increases.
When the temperature of the data input device 10 reaches a pre-determined temperature, the voltage at pin 5 will have increased enough to activate the electronic switch Q1, which results in the power pin 1 connecting to the I/O pins 2, 3 of the element switch Q1, which causes a portion of the current in the circuit to used by the resistor R1 and the diode D2, thus reducing the amount of current through the DC relay K, at which point the DC relay K opens to shut off the electronic heater EH. Optionally the indicator circuit 400 may be included. When Q1 turns off thus shutting off the electronic heater EH, the LED D3 emits light to indicate that the temperature of the data input device has reached the pre-determined temperature.
When it is not desired to heat the data input device 10, the switch S is opened to disconnect the DC relay K from the 5V power line VCC. The switch S can be mounted on an outside surface of the data input device 10.
Referring to
It is to be understood, however, that even though numerous characteristics and advantages of the present disclosure have been set forth in the foregoing description, together with details of the structure and function of the disclosure, the disclosure is illustrative only, and changes may be made in detail, especially in matters of shape, size, and arrangement of parts within the principles of the disclosure to the full extent indicated by the broad general meaning of the terms in which the appended claims are expressed.
Number | Date | Country | Kind |
---|---|---|---|
2008 1 0303617 | Aug 2008 | CN | national |
Number | Name | Date | Kind |
---|---|---|---|
3139575 | Brown | Jun 1964 | A |
3385957 | Munson et al. | May 1968 | A |
3858027 | Phillips | Dec 1974 | A |
4091266 | Ito et al. | May 1978 | A |
4167688 | Burek et al. | Sep 1979 | A |
5128521 | Lanno et al. | Jul 1992 | A |
6060698 | Petrides et al. | May 2000 | A |
6646226 | Reitz | Nov 2003 | B1 |
6650522 | Horibata et al. | Nov 2003 | B2 |
6894254 | Hauschulz | May 2005 | B2 |
20070216646 | Sun | Sep 2007 | A1 |
Number | Date | Country |
---|---|---|
2615749 | May 2004 | CN |
508608 | Nov 2002 | TW |
554161 | Sep 2003 | TW |
200736963 | Oct 2007 | TW |
Number | Date | Country | |
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20100032422 A1 | Feb 2010 | US |