Patent Publication Number: US-2003227272-A1

Title: Motor monitoring system

Description:
[0001] This application claims the benefit of Taiwan application Serial No. 091112259, filed Jun. 6, 2002.  
       BACKGROUND OF THE INVENTION  
       [0002] 1. Field of the Invention  
       [0003] The invention relates in general to a motor monitoring system, and more particularly to a motor monitoring system designed to monitor and adjust a motor&#39;s rotational speed according to the ambient temperature.  
       [0004] 2. Description of the Related Art  
       [0005] Please refer to FIG. 1, a diagram illustrating a conventional motor monitoring system  100 . The motor  150  could be an electric fan. The motor monitoring system  100  can be equipped in a notebook computer. A notebook computer with the motor monitoring system has the function of auto-temperature adjustment by controlling the rotational speed of the electric fan according to the ambient temperature. To meet the requirements of various rotational speeds under different temperature, the motor used herein needs to has the function of rotational speed setting. The conventional motor monitoring system  100  includes a chipset  110  in a computer, a monitoring unit  120 , a digital to analog converter D/A  130 , a charge pump  140  and a motor  150 . According to the inputted temperature reading of the interior of the notebook computer, the chipset  110  outputs a signal for controlling the rotational speed of the fan to the monitoring unit  120 . The monitoring unit  120  then outputs a control signal. The control signal is then transformed to an analog signal by the D/A  130  and inputted to the charge pump  140 . The charge pump  140  controls the rotational speed of the motor  150  according to the analog signal. The motor  150  has the function of outputting the rotational frequency f, which is fed back to the monitoring unit  120 . In accordance with the rotational frequency f, the monitoring unit  120  can modify the outputting control signal. To optimize the speed of the motor  100 , the conventional monitoring system  100  must include complex voltage regulators like the D/A and charge pump mentioned above, which directly influence the cost of the whole motor monitoring system.  
       SUMMARY OF THE INVENTION  
       [0006] It is therefore an object of the invention to provide a monitoring system of motor that has a simple and easy framework.  
       [0007] The invention achieves the above-identified objects by providing a monitoring system of motor that includes a control chip and a motor. The control chip is used to receive a temperature reading and output a control signal according to the temperature reading. The motor is used to receive the control signal and automatically adjust the speed of its own according to the control signal.  
       [0008] Other objects, features, and advantages of the invention will become apparent from the following detailed description of the preferred but non-limiting embodiments. The following description is made with reference to the accompanying drawings. 
     
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
     [0009]FIG. 1 (Prior Art) is a diagram illustrating a conventional motor monitoring system;  
     [0010]FIG. 2 is a diagram illustrating a motor monitoring system according to the first embodiment of the invention;  
     [0011]FIG. 3 is a diagram illustrating a motor monitoring system according to the second embodiment of the invention; and  
     [0012]FIG. 4 is a diagram illustrating a motor monitoring system according to the third embodiment of the invention. 
    
    
     DETAILED DESCRIPTION OF THE INVENTION  
     [0013] Please refer to FIG. 2, a diagram illustrating a motor monitoring system  200  according to the first embodiment of the invention. The motor  250  can automatically adjust the rotation speed of its own according to an inputted control signal, such as a waveform-controlled signal. And the waveform-controlled signal can be a pulse width modulation PWM control signal. The motor  250  operates according to the inputted control signal PWM. The frequency signal FG is further fed back to the control chip  210  so that the control chip  210  is informed of the rotational frequency. The control chip  210  is preferred to be a computer chipset or a monitoring chip. The control signal PWM from the control chip  210  is determined by the measured temperature and the fed-back frequency signal FG. As a result of the design, the configuration of the monitoring system is simplified, the R&amp;D flow is shortened, and the cost of R&amp;D and manufacturing are greatly reduced.  
     [0014] Please refer to FIG. 3, a diagram illustrating a motor monitoring system  300  according to the second embodiment of the invention. This monitoring system can be preferably applied in a notebook computer. A built-in FSC IC of the motor  300  functions to control the rotational speed. The built-in FSC IC can be further controlled by a chip set in the computer or another FSC IC. The motor monitoring system  300  includes a control chip  310  and a motor  350 . The motor  350  is a frequency-controlled motor, which receives the frequency-controlled signal Ctrl and operates accordingly. The motor  350  of this embodiment is not required to feed the rotational frequency back to the control chip  310 . The frequency-controlled signal Ctrl, which controls the rotational speed of the motors  350 , for example, of the fan, is mainly determined by the measured ambient temperature. Hence, according to the second embodiment of the invention, the configuration of the monitoring system is simplified, the R&amp;D flow is shortened, and the cost of R&amp;D and manufacturing are greatly reduced.  
     [0015] The motor monitoring system  300  is an open-loop control system, which contributes to simplify the configuration. However, the recovery from the breakdown of an open-loop control system is a task. To prevent severe breakdown, the motor  350  can be further equipped with an alarm  370 , which produces a warning while the motor operates in an unusual way, such as cease of rotation due to being locked or slow rotation down to a predetermined level. The alarm  370  can be, for example, an apparatus to give a warning sound or a flashing alert.  
     [0016] Please refer to FIG. 4, a diagram illustrating a motor monitoring system  400  according to the third embodiment of the invention. The motor monitor system  400  includes the control chip  410  and the motor  450 . The motor  450  is a frequency-controlled motor, which receives the frequency-controlled signal FSC and operates accordingly. The motor  450  further feeds a frequency signal FG, with the data of the rotational frequency, back to the control chip  410 . The frequency-controlled signal FSC, which controls the rotational speed of the motors  450 , for example, of the fan, is determined by both the measured ambient temperature and the frequency signal FG.  
     [0017] The motor monitoring system according to the invention disclosed in the foregoing embodiments can simplify the configurations of the monitoring system and shorten R&amp;D flow, and also reduce the cost of R&amp;D and manufacturing.  
     [0018] In the above description, the motor monitoring system is stalled in a notebook computer, as an example. However, the invention is not limited thereto. On the contrary, the motor monitoring system can be installed in any kind of computers, or a control system of an industrial motor.  
     [0019] While the invention has been described by way of example and in terms of a preferred embodiment, it is to be understood that the invention is not limited thereto. On the contrary, it is intended to cover various modifications and similar arrangements and procedures, and the scope of the appended claims therefore should be accorded the broadest interpretation so as to encompass all such modifications and similar arrangements and procedures.