Fan system and real-time stopping device thereof

• US 7,696,706 B2
• Filed: 12/14/2006
• Issued: 04/13/2010
• Est. Priority Date: 12/23/2005
• Status: Active Grant

• Current Assignee: Delta Electronics Incorporated
• Original Assignee: Delta Electronics Incorporated
• Inventors: Chiu, Chun-Lung, Chiu, Chin-Fa, Huang, Wen-Shi
• Primary Examiner(s): Ro; Bentsu
• Assistant Examiner(s): Luo; David S
• Application Number:
  US11/638,559
• Publication Number:
  US 20070145923A1
• Time in Patent Office: 1,216 Days
• Field of Search: 318/375, 318/362, 318/275, 318/563, 318/379, 318/381, 417/423.8, 417/423.1, 417/410.1
• US Class Current: 318/375
• CPC Class Codes: H02P 3/12 by short-circuit or resistive braking
• CPC Class Codes: H02P 6/24 Arrangements for stopping

Abstract

A fan system includes a stator magnetic pole, a driving unit and a real-time stopping unit. The driving unit is coupled with the stator magnetic pole and controls a polarity change of the stator magnetic pole in accordance with a driving signal. The real-time stopping unit is electrically connected with the driving unit. When the fan system is powered off, the driving unit enables two ends of the stator magnetic pole to have the same voltage level in accordance with a control signal generated by the real-time stopping unit so that the fan system stops operating immediately.

Claims

1. A fan system, comprising:

a stator magnetic pole;

a driving unit coupled with the stator magnetic pole for controlling a polarity change of the stator magnetic pole in accordance with a driving signal; and

a real-time stopping unit directly electrically connected with the driving unit and having a first switch element, second switch element, an energy storage and a resistor, wherein the energy storage is electrically connected with the first switch element and the second switch element, the resistor is electrically connected with the energy storage so as to enable the energy storage to discharge rapidly;

when the fan system is powered off, the energy storage is initially discharged, and the driving unit enables two ends of the stator magnetic pole to have the same voltage level in accordance with a control signal generated by the real-time stopping unit so that the fan system stops operating immediately.

2. The fan system according to claim 1, wherein the driving unit comprises a bridge circuit, a full-bridge circuit or a half-bridge circuit.

3. The fan system according to claim 2, wherein the stator magnetic pole has a first coil and a second coil, the half-bridge circuit has a first transistor and a second transistor, the first transistor is electrically connected with the first coil, the second transistor is electrically connected with the second coil, and the control signal turns on the first transistor and the second transistor.

4. The fan system according to claim 3, wherein the first transistor and the second transistor are NMOS transistors, respectively.

5. The fan system according to claim 2, wherein the full-bridge circuit comprises a lower bridge element composed of a first transistor and a second transistor, and an upper bridge element composed of a third transistor and a fourth transistor, and the lower bridge element turns on simultaneously in accordance with the control signal.

6. The fan system according to claim 5, wherein the first transistor and the second transistor are NMOS transistors, and the third transistor and the fourth transistor are PMOS transistors.

7. The fan system according to claim 2, further comprising a first Zener diode and a second Zener diode, wherein the first Zener diode and the second Zener diode are connected with the stator magnetic pole and the bridge circuit.

8. The fan system according to claim 1, wherein the driving signal is a pulse width modulation (PWM) signal.

9. The fan system according to claim 1, wherein the first switch element and the second switch element are transistors or NMOS transistors.

10. The fan system according to claim 1, wherein the energy storage is a capacitor or a capacitor having a small capacitance.

11. The fan system according to claim 1, wherein when the fan system is powered off, the first switch element and the second switch element turn off simultaneously, and the energy storage generates the control signal to enable the two ends of the stator magnetic pole to have the same voltage level so that the fan system stops operating immediately.

12. The fan system according to claim 1, further comprising a first diode and a second diode, wherein one end of the first diode is electrically connected with the second diode, and another end of the first diode is electrically connected with the real-time stopping unit.

13. The fan system according to claim 1, wherein the fan system is an axial-flow fan system or a centrifugal fan system.

14. A real-time stopping device of a fan system, the fan system having a stator magnetic pole and a driving unit, wherein the driving unit is coupled with the stator magnetic pole and controls a polarity change of the stator magnetic pole in accordance with a driving signal, the real-time stopping device comprising a real-time stopping unit directly electrically connected with the driving unit, wherein the real-time stopping unit has a first switch element, second switch element, an energy storage and a resistor, the energy storage is electrically connected with the first switch element and the second switch element, the resistor is electrically connected with the energy storage so as to enable the energy storage to discharge rapidly and when the fan system is powered off, the energy storage is initially discharged, and when the fan system is powered off, the energy storage is initially discharged, and the driving unit enables two ends of the stator magnetic pole to have the same voltage level in accordance with a control signal generated by the real-time stopping unit so that the fan system stops operating immediately.

15. The device according to claim 14, wherein the first switch element and the second switch element are transistors or NMOS transistors.

16. The device according to claim 14, wherein the real-time stopping unit further comprises a resistor electrically connected with the energy storage, and the energy storage is a capacitor or a capacitor having a small capacitance.

17. A fan system, comprising:

a stator magnetic pole;

a driving unit coupled with the stator magnetic pole for controlling a polarity change of the stator magnetic pole in accordance with a driving signal; and

a real-time stopping unit comprising an energy storage and electrically connected with the driving unit and having a first switch element, second switch element, an energy storage and a resistor, wherein the energy storage is electrically connected with the first switch element and the second switch element, the resistor is electrically connected with the energy storage so as to enable the energy storage to discharge rapidly;

when the fan system is powered off, the energy storage is initially discharged, and the driving unit enables two ends of the stator magnetic pole to have the same voltage level in accordance with a control signal generated by the energy storage of the real-time stopping unit so that the fan system stops operating immediately.