Patent Publication Number: US-8979512-B2

Title: Oil-retaining bearing having magnetic stabilizer

Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates generally to an oil-retaining bearing fan device, and more particularly to an oil-retaining bearing fan device including at least one magnetic member. The magnetic member serves to apply a magnetic attraction force to a shaft of the fan device to make the shaft quickly restore to its optimal operation position so as to reduce wear and lower the noises and vibration of the fan device in operation. Therefore, the lifetime of the fan device can be prolonged. 
     2. Description of the Related Art 
     Recently, all kinds of electronic information products (such as computers) have been more and more popularly used and widely applied to various fields. There is a trend to increase processing speed and expand access capacity of the electronic information products. Therefore, the electronic components of the electronic information products have operated at higher and higher speed. When operating at high speed, the electronic components generate high heat at the same time. 
     With a computer host taken as an example, the central processing unit (CPU) in the computer host generates most of the heat generated by the computer host in operation. In case the heat is not efficiently dissipated, the temperature of the CPU will rise very quickly to cause deterioration of the execution efficiency. When the accumulated heat exceeds a tolerable limit, the computer will crash or even burn down in some more serious cases. Moreover, for solving the problem of electromagnetic radiation, the computer host is often enclosed in a computer case. This will affect the dissipation of the heat generated by the computer host. Therefore, it has become a critical issue how to quickly conduct out and dissipate the heat generated by the CPU and other heat-generating components. 
     Conventionally, a heat sink and a cooling fan are arranged on the CPU to quickly dissipate heat. One side of the heat sink has multiple radiating fins, while the other side of the heat sink is free from any radiating fin. The surface of the other side of the heat sink directly contacts the CPU for conducting heat to the radiating fins. The radiating fins serve to dissipate the heat by way of radiation. In addition, the cooling fan cooperatively forcedly drives airflow to quickly carry away the heat. 
       FIG. 1  is a perspective sectional assembled view of a conventional oil-retaining bearing cooling fan. The cooling fan  1  includes a fan base seat  11 . A bearing cup  111  protrudes from the fan base seat  11 . A bearing  12  is disposed in the bearing cup  111 . A fan impeller  13  is assembled with the fan base seat  11 . The fan impeller  13  has multiple blades  131  annularly arranged along outer circumference of the fan impeller  13 . The fan impeller  13  further has a shaft  132  extending from an inner side of the fan impeller  13 . The shaft  132  is disposed and located in the bearing  12 . An oil film  121  is filled between the bearing  12  and the shaft  132 . The relative position between the fan base seat  11 , the bearing  12  and the fan impeller  13  is tested and adjusted to an optimal operation position where the shaft  132  of the cooling fan  1  can stably rotate within the bearing  12  under support of the oil film  121 . Accordingly, in operation of the cooling fan  1 , the shaft  132  rotates within the bearing  12  in an operation position relative to the bearing  12  only under the support force of the oil film  121 . However, the support force of the oil film  121  provided for the shaft  132  is smaller than the eccentric force applied to the shaft  132  in operation of the cooling fan  1 . Therefore, the shaft  132  and the bearing  12  will still abrade and collide each other. Also, in case the cooling fan  1  is collided by an alien article to make the shaft  132  deflected from its true position, the shaft  132  will collide the bearing  12  and vibrate in operation. Under such circumstance, in operation, the cooling fan  1  will vibrate and make noises due to the deflection of the shaft  132 . Moreover, the wear between the shaft  132  and the bearing  12  will be increased to shorten lifetime of the cooling fan  1 . The shaft  132  may be restored to its optimal operation position under the support force of the oil film  121 . However, after squeezed, it takes longer time for the oil film  121  to recover so that the shaft  132  also needs longer time to restore to its optimal operation position. As a result, the noises will last longer. 
     According to the above, the conventional oil-retaining bearing cooling fan has the following shortcomings:
         1. The conventional oil-retaining bearing cooling fan tends to vibrate and make noises.   2. The conventional oil-retaining bearing cooling fan is more subject to wear.   3. The noises made by the conventional oil-retaining bearing cooling fan will last longer.   4. The lifetime of the conventional oil-retaining bearing cooling fan is shorter.       

     SUMMARY OF THE INVENTION 
     A primary object of the present invention is to provide an oil-retaining bearing fan device including at least one magnetic member. The magnetic member serves to apply a magnetic attraction force to a shaft of the fan device to make the shaft quickly restore to its optimal operation position so as to reduce wear and lower the noises and vibration of the fan device in operation. Therefore, the lifetime of the fan device can be prolonged. 
     A further object of the present invention is to provide the above oil-retaining bearing fan device, which can quickly restore to a stably operating state. 
     To achieve the above and other objects, the oil-retaining bearing fan device of the present invention includes a fan base seat, at least one oil-retaining bearing, at least one magnetic member and a fan impeller. The fan base seat has a bearing cup on one side. The bearing cup has a bearing hole. The oil-retaining bearing is disposed in the bearing hole. The oil-retaining bearing has a shaft hole and at least one receiving hole. The magnetic member is disposed in the receiving hole. The fan impeller has multiple blades and a shaft. The shaft is rotatably disposed in the shaft hole. The magnetic member serves to apply a magnetic attraction force to the shaft to make the shaft quickly restore to its optimal operation position so as to reduce wear and lower the noises and vibration of the fan device in operation. Therefore, the lifetime of the fan device can be prolonged. 
     According to the above arrangement, the present invention has the following advantages: 
     1. The noises and vibration of the fan device are lowered. 
     2. The wear of the fan device is reduced. 
     3. The lasting time of the noises is shortened. 
     4. The lifetime of the fan device is prolonged. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The structure and the technical means adopted by the present invention to achieve the above and other objects can be best understood by referring to the following detailed description of the preferred embodiments and the accompanying drawings, wherein: 
         FIG. 1  is a perspective sectional assembled view of a conventional oil-retaining bearing cooling fan; 
         FIG. 2  is a perspective sectional assembled view of a first embodiment of the present invention; 
         FIG. 3  is a plane view of a part of the first embodiment of the present invention; 
         FIG. 4  is a perspective sectional assembled view of a second embodiment of the present invention; 
         FIG. 5  is a plane view of a part of the second embodiment of the present invention; 
         FIG. 6  is a perspective sectional assembled view of a third embodiment of the present invention; 
         FIG. 7  is a plane view of a part of the third embodiment of the present invention; 
         FIG. 8  is a perspective sectional assembled view of a fourth embodiment of the present invention; and 
         FIG. 9  is a plane view of a part of the fourth embodiment of the present invention. 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     Please refer to  FIGS. 2 and 3 .  FIG. 2  is a perspective sectional assembled view of a first embodiment of the present invention.  FIG. 3  is a plane view of a part of the first embodiment of the present invention. According to the first embodiment, the oil-retaining bearing fan device  2  of the present invention includes a fan base seat  21 , an oil-retaining bearing  22 , a magnetic member  23  and a fan impeller  24 . The fan base seat  21  has a bearing cup  211  on one side. The bearing cup  211  has an internal bearing hole  2111  in which the oil-retaining bearing  22  is disposed. The oil-retaining bearing  22  has an internal shaft hole  221  and at least one receiving hole  222 . 
     In this embodiment, the receiving hole  222  is disposed on an inner circumference of the oil-retaining bearing  22 . The magnetic member  23  is disposed in the receiving hole  222 . The magnetic member  23  is selected from a group consisting of magnetic iron, magnetic powder body and magnet. The fan impeller  24  includes multiple blades  241  and a shaft  242 . The blades  241  are annularly arranged along outer circumference of the fan impeller  24 . The fan impeller  24  is disposed on the bearing cup  211  with the shaft  242  rotatably disposed in the shaft hole  221 . A hydraulic layer  223 , which is an oil film, is filled between the shaft  242  and a wall of the shaft hole  221 . When mounting the shaft  242  into the shaft hole  221 , it is necessary to test and adjust the relative position between the fan base seat  21 , the oil-retaining bearing  22  and the fan impeller  24  to an optimal operation position. When adjusting the position, the magnetic member  23  received in the receiving hole  222  applies a magnetic attraction force to the shaft  242 . In the meantime, the hydraulic layer  223  provides a support force for the shaft  242 . By means of the magnetic attraction force of the magnetic member  23  and the support force of the hydraulic layer  223 , the shaft  242  can be effectively located in the optimal operation position. In operation of the fan impeller  24 , under the magnetic attraction force of the magnetic member  23 , the shaft  242  can be kept in the optimal operation position. Accordingly, the stability of operation of the shaft  242  within the oil-retaining bearing  22  can be enhanced to reduce wear and lower the noises and vibration of the fan device in operation. Therefore, the lifetime of the fan device can be prolonged. 
     On the other hand, in case in the oil-retaining bearing fan device  2  is collided by an alien article to make the shaft  242  deflected from its true position, the shaft  242  will collide the oil-retaining bearing  22  and vibrate. Under such circumstance, the magnetic member  23  will apply a magnetic attraction force to the shaft  242 , making the shaft  242  quickly restore to its optimal operation position so as to reduce wear and lower the noises and vibration of the fan device in operation. Therefore, the lifetime of the fan can be prolonged. 
     Please refer to  FIGS. 4 and 5 .  FIG. 4  is a perspective sectional assembled view of a second embodiment of the present invention.  FIG. 5  is a plane view of a part of the second embodiment of the present invention. The second embodiment is substantially identical to the first embodiment in component, connection relationship and operation and thus will not be repeatedly described hereinafter. The second embodiment is different from the first embodiment in that the receiving hole  222  is disposed on an outer circumference of the oil-retaining bearing  22 . The magnetic member  23  is disposed in the receiving hole  222 . The shaft  242  is rotatably disposed in the shaft hole  221 . The hydraulic layer  223  is filled between the shaft  242  and the wall of the shaft hole  221 . When mounting the shaft  242  into the shaft hole  221 , it is necessary to test and adjust the relative position between the fan base seat  21 , the oil-retaining bearing  22  and the fan impeller  24  to an optimal operation position. When adjusting the position, the magnetic member  23  received in the receiving hole  222  applies a magnetic attraction force to the shaft  242 . In the meantime, the hydraulic layer  223  provides a support force for the shaft  242 . By means of the magnetic attraction force of the magnetic member  23  and the support force of the hydraulic layer  223 , the shaft  242  can be effectively located in the optimal operation position. In operation of the fan impeller  24 , under the magnetic attraction force of the magnetic member  23 , the shaft  242  can be kept in the optimal operation position. Accordingly, the stability of operation of the shaft  242  within the oil-retaining bearing  22  can be enhanced to reduce wear and lower the noises and vibration of the fan device in operation. Therefore, the lifetime of the fan device can be prolonged. On the other hand, in case in the oil-retaining bearing fan device  2  is collided by an alien article to make the shaft  242  deflected from its true position, the magnetic member  23  received in the receiving hole  222  will apply a magnetic attraction force to the shaft  242  to make the shaft  242  quickly restore to its optimal operation position so as to reduce wear and lower the noises and vibration of the fan device in operation. Therefore, the lifetime of the fan device can be prolonged. 
     Please refer to  FIGS. 6 and 7 .  FIG. 6  is a perspective sectional assembled view of a third embodiment of the present invention.  FIG. 7  is a plane view of a part of the third embodiment of the present invention. The third embodiment is substantially identical to the first embodiment in component, connection relationship and operation and thus will not be repeatedly described hereinafter. The third embodiment is different from the first embodiment in that the receiving hole  222  is disposed in the oil-retaining bearing  22  between the inner and outer circumferences thereof. The magnetic member  23  is disposed in the receiving hole  222 . The shaft  242  is rotatably disposed in the shaft hole  221 . The hydraulic layer  223  is filled between the shaft  242  and the wall of the shaft hole  221 . When mounting the shaft  242  into the shaft hole  221 , it is necessary to test and adjust the relative position between the fan base seat  21 , the oil-retaining bearing  22  and the fan impeller  24  to an optimal operation position. When adjusting the position, the magnetic member  23  received in the receiving hole  222  applies a magnetic attraction force to the shaft  242 . In the meantime, the hydraulic layer  223  provides a support force for the shaft  242 . By means of the magnetic attraction force of the magnetic member  23  and the support force of the hydraulic layer  223 , the shaft  242  can be effectively located in the optimal operation position. In operation of the fan impeller  24 , under the magnetic attraction force of the magnetic member  23 , the shaft  242  can be kept in the optimal operation position. Accordingly, the stability of operation of the shaft  242  within the oil-retaining bearing  22  can be enhanced to reduce wear and lower the noises and vibration of the fan device in operation. Therefore, the lifetime of the fan device can be prolonged. On the other hand, in case in the oil-retaining bearing fan device  2  is collided by an alien article to make the shaft  242  deflected from its true position, the magnetic member  23  received in the receiving hole  222  will apply a magnetic attraction force to the shaft  242  to make the shaft  242  quickly restore to its optimal operation position so as to reduce wear and lower the noises and vibration of the fan device in operation. Therefore, the lifetime of the fan device can be prolonged. 
     Please refer to  FIGS. 8 and 9 .  FIG. 8  is a perspective sectional assembled view of a fourth embodiment of the present invention.  FIG. 9  is a plane view of a part of the fourth embodiment of the present invention. The fourth embodiment is substantially identical to the first embodiment in component, connection relationship and operation and thus will not be repeatedly described hereinafter. The fourth embodiment is different from the first embodiment in that the oil-retaining bearing  22  has multiple receiving holes  222 . In this embodiment, two receiving holes  222  are, but not limited to, disposed on the outer circumference of the oil-retaining bearing  22 . (Alternatively, the receiving holes  222  can be disposed on the inner circumference of the oil-retaining bearing  22 , in the oil-retaining bearing  22  between the inner and outer circumferences thereof or respectively disposed on the inner and outer circumferences of the oil-retaining bearing  22 ). The magnetic members  23  are disposed in the receiving holes  222  to locate the shaft  242  in the optimal operation position. In operation of the fan impeller  24 , under the magnetic attraction force of the magnetic members  23 , the shaft  242  can be kept in the optimal operation position. Accordingly, the stability of operation of the shaft  242  within the oil-retaining bearing  22  can be enhanced to reduce wear and lower the noises and vibration of the fan device in operation. Therefore, the lifetime of the fan device can be prolonged. 
     The above embodiments are only used to illustrate the present invention, not intended to limit the scope thereof. It is understood that many changes and modifications of the above embodiments can be made without departing from the spirit of the present invention. The scope of the present invention is limited only by the appended claims.