# US 7,609,018 B2 · Fan system and control device thereof > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 7,609,018 B2 - Document ID: US7609018B2 - Status: Granted - Kind: B2 - Application number: 11/898,899 - Filed: 2007-09-17 - Published: 2008-03-27 - Granted: 2009-10-27 - Earliest claimed: 2006-09-22 - Assignees: Delta Electronics, Inc. - Inventors: Yu-Liang Lin; Tsung-Jung Hsieh; Yueh-Lung Huang; Ming-Shi Tsai - Web page: https://patentgrep.com/patent/US7609018B2 ## CPC - G06F 1/206: {comprising thermal management} - H05K 7/20209: {Thermal management, e.g. fan control} - Y10S 388/934: Thermal condition - G06F: ELECTRIC DIGITAL DATA PROCESSING (computer systems based on specific computational models G06N) - H05K: PRINTED CIRCUITS; CASINGS OR CONSTRUCTIONAL DETAILS OF ELECTRIC APPARATUS; MANUFACTURE OF ASSEMBLAGES OF ELECTRICAL COMPONENTS - Y10S: TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS ## Abstract A control device of a fan system includes a temperature sensing module, a comparing module and a driving module. The temperature sensing module senses an external temperature and generates a sensing signal according to the external temperature. The comparing module receives the sensing signal and outputs a comparing signal according to the sensing signal and a reference voltage signal. The driving module, which is electrically connected with the temperature sensing module and the comparing module, supplies a working voltage to the temperature sensing module and the comparing module, and outputs a rotating speed control signal according to the sensing signal or the comparing signal. ## Claims ### Claim 1 A control device of a fan system, comprising: a temperature sensing module for sensing an external temperature so as to generate a sensing signal; a comparing module for receiving the sensing signal and outputting a comparing signal according to the sensing signal and a reference voltage signal; and a driving module electrically connected with the temperature sensing module and the comparing module for supplying a working voltage to the temperature sensing module and the comparing module and outputting a rotating speed control signal according to the sensing signal or the comparing signal when the fan system is in a normal state, wherein when the fan system is in an abnormal state, the rotating speed control signal makes a motor of the fan system rotate at the full speed, wherein the abnormal state represents that a sensing member of the temperature sensing module is detached or broken. ### Claim 2 (depends on 1) The device according to claim 1, wherein when the reference voltage signal is higher than the sensing signal, the comparing signal is a high level signal. ### Claim 3 (depends on 2) The device according to claim 2, wherein the reference voltage signal is lower than the working voltage. ### Claim 4 (depends on 1) The device according to claim 1, wherein when the reference voltage signal is lower than the sensing signal, the comparing signal is a low level signal. ### Claim 5 (depends on 1) The device according to claim 1, wherein the sensing member is used for sensing the external temperature and generating the sensing signal according to the external temperature. ### Claim 6 (depends on 1) The device according to claim 1, wherein the temperature sensing module has a first resistor having a first end for receiving the working voltage, and the sensing member having a first end electrically connected with a second end of the first resistor so as to generate the sensing signal, and a second end grounded. ### Claim 7 (depends on 6) The device according to claim 6, wherein the sensing member is a positive temperature coefficient thermister or a negative temperature coefficient thermister. ### Claim 8 (depends on 1) The device according to claim 1, wherein the comparing module has a comparator having a first input terminal for receiving the reference voltage signal, a second input terminal for receiving the sensing signal, and an output terminal for outputting the comparing signal after the comparator compares the reference voltage signal with the sensing signal. ### Claim 9 (depends on 1) The device according to claim 1, wherein the comparing module comprises: a comparator having a first input terminal, a second input terminal for receiving the sensing signal, and an output terminal for outputting the comparing signal; a second resistor having a first end for receiving the working voltage, and a second end electrically connected with the first input terminal of the comparator; a third resistor having a first end electrically connected with the first input terminal of the comparator to generate the reference voltage signal, and a second end grounded; a fourth resistor having a first end for receiving the working voltage, and a second end electrically connected with the output terminal of the comparator; and a fifth resistor having a first end electrically connected with the second end of the fourth resistor and the output terminal of the comparator, and a second end grounded. ### Claim 10 (depends on 9) The device according to claim 9, wherein the comparator is an operational amplifier, and the driving module comprises a microprocessor or a chip. ### Claim 11 A fan system comprising: a control device comprising a temperature sensing module, a comparing module and a driving module, wherein the temperature sensing module senses an external temperature so as to generate a sensing signal, the comparing module receives the sensing signal and outputs a comparing signal according to the sensing signal and a reference voltage signal, and the driving module is electrically connected with the temperature sensing module and the comparing module, supplies a working voltage to the temperature sensing module and the comparing module, and outputs a rotating speed control signal according to the sensing signal or the comparing signal when the fan system is in a normal state; and a motor receiving the rotating speed control signal and controlled to rotate according to the rotating speed control signals, wherein when the fan system is in an abnormal state, the rotating speed control signal makes the motor rotate at the full speed, wherein the abnormal state represents that a sensing member of the temperature sensing module is detached or broken. ### Claim 12 (depends on 11) The fan system according to claim 11, wherein when the reference voltage signal is higher than the sensing signal, the comparing signal is a high level signal. ### Claim 13 (depends on 12) The fan system according to claim 12, wherein the reference voltage signal is lower than the working voltage. ### Claim 14 (depends on 11) The fan system according to claim 11, wherein when the reference voltage signal is lower than the sensing signal, the comparing signal is a low level signal. ### Claim 15 (depends on 11) The fan system according to claim 11, wherein the sensing member is used for sensing the external temperature and generating the sensing signal according to the external temperature. ### Claim 16 (depends on 11) The fan system according to claim 11, wherein the temperature sensing module has the first resistor having a first end for receiving the working voltage, and the sensing member having a first end electrically connected with a second end of the first resistor so as to generate the sensing signal, and a second end grounded. ### Claim 17 (depends on 16) The device according to claim 16, wherein the sensing member is a positive temperature coefficient thermister or a negative temperature coefficient thermister. ### Claim 18 (depends on 11) The fan system according to claim 11, wherein the comparing module has a comparator having a first input terminal for receiving the reference voltage signal, a second input terminal for receiving the sensing signal, and an output terminal for outputting the comparing signal after the comparator compares the reference voltage signal with the sensing signal. ### Claim 19 (depends on 18) The fan system according to claim 18, wherein the comparator is an operational amplifier. ### Claim 20 (depends on 11) The fan system according to claim 11, wherein the comparing module comprises: a comparator having a first input terminal, a second input terminal for receiving the sensing signal, and an output terminal for outputting the comparing signal; a second resistor having a first end for receiving the working voltage, and a second end electrically connected with the first input terminal; a third resistor having a first end electrically connected with the first input terminal of the comparator to generate the reference voltage signal, and a second end grounded; a fourth resistor having a first end for receiving the working voltage, and a second end electrically connected with the output terminal of the comparator; and a fifth resistor having a first end electrically connected with the second end of the fourth resistor and the output terminal of the comparator, and a second end grounded.