Patent Publication Number: US-2010115294-A1

Title: Delayed shutdown system for auxiliary power supply device of personal computer

Description:
FIELD OF THE INVENTION 
     The present invention relates to a delayed shutdown system applicable to an auxiliary power supply device of a computer, and in particular to a circuit design that provides a delayed shutdown circuit that is arranged on a slave power supply interface card and connected to the auxiliary power supply device so that when the computer is shut down (namely a main board or a primary power supply device being shut down), a shutdown signal is transmitted to the slave power supply interface card to cause a delayed shutdown of the auxiliary power supply device, allowing the auxiliary power supply device to maintain supplying of electrical power to peripheral devices whereby the peripheral devices, although staying in a signal silent condition caused by the shutdown of the computer, remains capable to smoothly shut down, this being applicable to a desktop computer system, a thin client computer system, a miniature computer system, and the likes. 
     BACKGROUND OF THE INVENTION 
     With the quick development of technology, computer systems evolve fast from the early DOS system, WINDOWS system, to the recently available VISTA system. The operation speed gets increasingly fast and consequently, high-standard computer hardware is required, including at least central processing unit (CPU), memory, and graphic acceleration card. The computer peripheral devices are also getting versatile, such as high-speed optic disk drive, external backup hard disk drive, card reader, USB slot, heat dissipation fan and the likes. 
     Conventionally, the computer hardware and the peripheral devices are both powered by the same power supply device. Apparently, the load of supplying power from the power supply device gets heavy with the development of the computer and peripheral devices and high power (wattage) power supply devices are needed to sufficiently supply power to the computer hardware and the associated peripheral devices. In addition, due to the different specifications that the hardware may take, the power supply device has to be upgraded with the development of the computer hardware. For example, the old type power supply device of former P2 or P3 specification is not suitable for a computer main board of P4 specification. Thus, the power supply devices are also of various models, such as AT and ATX. 
     For example,  FIG. 7  of the attached drawings illustrate a layout of multiple electrical connection ports on a circuit board of a conventional power supply device, which is of an ATX model having 24 pins or terminals. On the other hand, an AT model has only 20 pins. Both the ATX model and the AT model provide multiple electrical input/output pins, among which a PS-ON/PS-OFF pin receives an input of a PS-ON/PS-OFF signal. An input of the PS-ON signal starts up the power supply device, while an input of the PS-OFF signal shuts down the power supply device. In the operation of the power supply, some of the pins supply output voltages of for example 24V, 12V, 5V and 3.3V. On the other hand, when the power supply device is shut down, these pins provide no voltage and electrical power. Thus, controlling the input signal to the PS-ON/PS-OFF pin may selectively start up or shut down all the peripheral devices that are supplied with power from the power supply device. The present invention provides a delayed shutdown system for an auxiliary power supply device of a computer, of which the auxiliary power supply device has an electrical connection port of which the 16th pin functions to provide the PS-ON/PS-OFF signal for controlling the ON/OFF states of the auxiliary power supply device. 
     Currently, one of the most commonly known ways of upgrading computer hardware or peripheral devices is to remove and replace a small power (wattage) power supply device or one that does not meet the new P4 standards with a new power supply. The removed old power supply device is then disposed of and treated as a waste. 
     Due to the current trend of environmental conservation, simply disposing of a small power (wattage) power supply device or one that does not meet the new standards without a though for re-using may cause pollution to the environment and a creation of garbage. This is ironic for the modern society that seeks for sustainable use of the natural environment. 
     In addition, when a computer is shut down, it may simply follow prescribed process to shut down in a normal way, or it may shut down abnormally without following the prescribed shutdown process. For a normal shutdown, data can be properly stored or a magnetic head can be properly set. However, for abnormal shutdown, which often occurs abruptly, data may get lost and magnetic disk or magnetic head is damaged. Abrupt power off often leads to inadvertent damage to disk drives. 
     Further, conventionally, fans and water pumps will immediately shut down when a computer is shut down. However, electronic parts of the computer that are already put in high temperature by the operation and process executed for shutting down the computer. Additionally, immediately after the computer is shut down, saturated capacitors of the computer continue discharge of electricity. Thus, the temperature of the computer rises to an apex point without any head dissipation realized by the heat dissipation facility that is shut down with the computer. This is referred to as temperature rising effect. This often causes burn-down of the electronic parts or chips. Apparently, it is insufficient to cool down with only by natural convection of air flow (with no operation of the head dissipation facility) after the computer is shut down. 
     Thus, the present inventor attempts to provide a delayed shutdown system that uses an old-fashion and out-of-date as a secondary, auxiliary power supply device for a computer system to share the load of power supply with a primary power supply device of the computer system and to effect s delayed shutdown after the computer system is shut down, for the purposes of overcoming the above discussed problems and drawbacks. 
     SUMMARY OF THE INVENTION 
     An objective of the present invention is to provide a delayed shutdown system applicable to an auxiliary power supply device of a personal computer, wherein a slave power supply interface card comprises a delayed shutdown circuit that allows the auxiliary power supply device to be shut down in a delayed fashion whereby after the computer is shut down, the auxiliary power supply device maintains in operation for a preset time period for maintaining the operation of peripheral devices coupled thereto until the peripheral devices are safely and smoothly shut down, thereby enhancing safety of the computer system. 
     Another objective of the present invention is to provide a delayed shutdown system for an auxiliary power supply device of a personal computer, which allows for simultaneous operation of two power supply devices associated with a single computer by means of a signal connection port provided on a slave power supply interface card in communication with the computer, wherein the signal connection port functions to receive a voltage-on or voltage-off signal (Vout≠0/Vout=0), which signal is converted and applied to the auxiliary power supply device through an electrical connection port provided on the slave power supply interface card for controlling the switching of the auxiliary power supply device between ON and OFF states so that the auxiliary power supply can be simultaneously turned on/off with the computer and serves as a slave power supply to the computer. As such, the whole computer system can be started up or shut down through actuation of a signal button and the convenience of operation of the computer system is enhanced. 
     To realize the above objective, the present invention provides a delayed shutdown system that is applicable to a computer system comprising two power supply devices including a primary power supply device and a secondary, auxiliary power supply device and a slave power supply interface card, wherein the primary power supply device is arranged in a computer host of the computer system and electrically connected to a computer main board to supply electrical power thereto and the secondary power supply device is connected to peripheral devices via the slave power supply interface card to provide additional electrical power thereto. The slave power supply interface card is inserted into and engages an expansion slot of the computer main board or is connected thereto by conductors. The slave power supply interface card comprises an electrical connection port, at least one power output port, a signal connection port, and a delayed shutdown circuit. The electrical connection port is electrically connected to the secondary power supply device for supplying the additional electrical power from the secondary power supply device to the slave power supply interface card so that the additional electrical power is further supplied to the peripheral devices via the at least one power output port. The signal connection port is in signal connection with the computer host (the main board or the primary power supply device) to receive a host shutdown signal from the computer host (the main board or the primary power supply device). The host shutdown signal is transmitted to the delayed shutdown circuit whereby a preset delayed shutdown time period set in the delayed shutdown circuit. The secondary power supply device is maintained in operation until the preset delayed shutdown time period has elapsed, whereby during the preset delayed shutdown time period, the secondary power supply device maintains the additional supply of electrical power that provides the peripheral devices with sufficient time to return to a home position/an original condition for shutdown and/or to sufficiently dissipate heat therefrom. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The present invention will be apparent to those skilled in the art by reading the following description of preferred embodiments thereof with reference to the drawings, in which: 
         FIG. 1  is a perspective view illustrating a first embodiment of the present invention; 
         FIG. 2  is an exploded view of the first embodiment of the present invention; 
         FIG. 3  is a schematic plan view of a slave power supply interface card in accordance with the present invention; 
         FIG. 4  is a perspective view illustrating a second embodiment of the present invention; 
         FIG. 5  is a schematic view illustrating a portion of the second embodiment of the present invention; 
         FIG. 6  is a block diagram of the present invention; and 
         FIG. 7  illustrates a layout of multiple electrical connection ports of a conventional power supply device. 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     With reference to the drawings and in particular to  FIGS. 1-3 , which show a delayed shutdown system constructed in accordance with a first embodiment of the present invention applicable to an auxiliary power supply of a personal computer, the delayed shutdown system is composed of two power supply devices, namely a primary power supply device  21  and a secondary power supply device  30 , and a slave power supply interface card  10 . The primary power supply device  21  is built in the personal computer  20  and is electrically connected to a computer main board  22  to supply electrical power thereto. The secondary power supply device  30  is electrically connected to the slave power supply interface card  10  to provide additional electrical power. The slave power supply interface card  10  is inserted in and engages an expansion slot  221  of the main board  22 . The slave power supply interface card  10  forms an electrical connection port  11 , at least one power output port  12 , a signal connection port  13 , and a delayed shutdown circuit  14 . The electrical connection port  11  is electrically connected to the secondary power supply device  30  for supplying the electrical power from the secondary power supply device  30  to the slave power supply interface card  10  and such electrical power is further supplied to peripheral devices  40  via connection thereof with the at least one power output port  12 . The signal connection port  13  is in signal connection with the main board  22  to receive a shutdown signal from the main board  22 . The shutdown signal is applied to the delayed shutdown circuit  14  to initiate a preset delayed shutdown countdown time period. The secondary power supply device  30  is not shut down until the countdown is completed and the preset delayed time period has elapsed. During the delayed shutdown time period, the secondary power supply device  30  maintains the supply of electrical power that provides the peripheral devices  40  with sufficient time and power supply to return to the home position or original condition for shutdown and/or to sufficiently dissipate heat therefrom. 
     In use, when the computer  20  is booted up and the primary power supply device  21  is set in operation (Vout≠0), with the connection of the main board  22  with the signal connection port  13  of the slave power supply interface card  10 , a voltage-on signal (Vout≠0) is fed through a signal line  23  to the slave power supply interface card  10 . The slave power supply interface card  10  converts the voltage-on signal (Vout≠0) into a PS-ON signal that is then applied to the electrical connection port  11  of the slave power supply interface card  10  and is further transmitted to the secondary power supply device  30  via a signal line  32  to thereby turn on the operation of the secondary power supply device  30  in a substantially synchronous manner, whereby the additional electrical power supplied due to the operation of the secondary power supply device  30  is fed back to the slave power supply interface card  10  and further supplied to the peripheral devices  40  through the at least one power output port  12 . The peripheral devices  40  can be for example one or more of a floppy disk drive, a hard disk drive  41 , an optic disk drive  42 , a computer enclosure mounted fan  43 , a CPU (Central Processing Unit) fan, a display card fan, a heat dissipation fan, and a water pump. The additional electrical power supplied from the secondary power supply device  30  is used to start up the operation of the peripheral devices  40 . Due to the fact that two power supply devices are simultaneously used, the total amount of electrical power supplied is increased, which allows for operating extra facility. 
     When the computer system is shut down by turning off the primary power supply device  21  (Vout=0), due to the connection of the main board  22  with the slave power supply interface card  10 , a voltage-off signal (Vout=0) is fed through the signal line  23  to the slave power supply interface card  10  and is forwarded through the signal connection port  13  to the delayed shutdown circuit  14  to initiate the countdown of the preset delayed shutdown time period that is set by the delayed shutdown circuit  14 . In the respect, the delayed shutdown circuit  14  comprises a timer circuit  141  for time countdown. The timer circuit  141  can be set by factory or a user, or can be automatically set in accordance with environmental factors or through a preset logic algorithm. The environmental factor based setting of the timer circuit  141  can be operated on the basis of inside-enclosure detected temperature level, a preset value, or an operation condition flag of the computer. After the time delay has elapsed, the delayed shutdown circuit converts the voltage-off signal into a PS-OFF signal that is transmitted to the secondary power supply device  30 . In this way, the shutdown of the power supply from the secondary power supply device  30  is delayed a preset time period, and this provides the peripheral devices  40  that are electrically connected to the power output port  12  of the slave power supply interface card  10  with sufficient time to return to the home position or original condition and/or sufficiently dissipate heat therefrom. The peripheral devices  40  can be for example one or more of a floppy disk drive, a hard disk drive  41 , an optic disk drive  42 , a computer enclosure mounted fan  43 , a CPU fan, a display card fan, a heat dissipation fan, and a water pump. Thus, the shutdown of the peripheral devices is delayed, which allows the shutdown of the system more complete and smooth whereby enhanced stability and safety of the system can be obtained. 
     Referring to  FIGS. 3-5 , which show a second embodiment of the present invention, the slave power supply interface card  10  comprises an electrical connection port  11 . Power lines  31  and signal lines  32  electrically connect among the slave power supply interface card  10 , an adaptor box  50 , and a secondary power supply device  30 . Electrical power is supplied from the secondary power supply device  30  through the adaptor box  50  to the slave power supply interface card  10  for further supply to the peripheral devices  40  through at least one power output port  12 . In other words, the adaptor box  50  is arranged between the secondary power supply device  30  and the slave power supply interface card  10  and the electrical connection port  11  is electrically connected to the adaptor box  50  through the power line  31 . The adaptor box  50  comprises and contains therein a power conversion circuit  51 . The electrical power from the secondary power supply device  30  is subjected to conversion by the power conversion circuit  51  into a desired voltage level (including for example 24V, 12V, 5V, and 3.3V) that is supplied through a power line  31  to the slave power supply interface card  10  for output through the at least one power output port  12 . The adaptor box  50  can be provided with various external power connection ports  52  of various voltage levels for selective connection with external peripheral devices  48 , such as a liquid crystal display, an external hard disk drive, an ADSL modem, a switching type hub, a rechargeable wireless mouse, and a scanner. The external peripheral devices  48  can be plugged into the external power connection ports  52  of the adaptor box  50  to receive the desired voltage level and electrical power. Although not illustrated in the drawings, optionally, the secondary power supply device  30  can be mounted inside the computer  20 , whereby the computer  20  possesses two power supply devices of which a primary power supply device  21  is electrically connected to a main board  22  for supplying electrical power to the main board  22 . The primary power supply device  21  is also set in electrical connection with the slave power supply interface card  10  via a signal line  23  to feed a voltage-on/voltage-off signal to the slave power supply interface card  10 . The slave power supply interface card  10  converts the voltage-on/voltage-off signal (Vout≠0/Vout=0) into a PS-ON/PS-OFF signal that starts up and/or shuts down the secondary power supply device  30 , whereby with the electrical connection of the electrical connection port  11  of the slave power supply interface card  10  with the secondary power supply device  30  through the power line  31  and the signal line  32 , the signal is applied to the secondary power supply device  30  to start up or shut down the secondary power supply device  30  for supply of the additional electrical power. The secondary power supply device  30  can be directly connected to peripheral devices  40  of the computer  20  to supply the electrical power desired thereby. The peripheral devices  40  of the computer  20  can be for example one or more of a floppy disk drive, a hard disk drive  41 , an optic disk drive  42 , a computer enclosure mounted fan  43 , a CPU fan, a display card fan, a heat dissipation fan, and a water pump. For environmental conservation, the secondary power supply device  30  can be a used, old-fashion power supply device or a low wattage power supply. In this way, the quantity of the disposed power supply devices can be reduced and the frequency of replacing or upgrading power supply devices is decreased. Although the primary power supply device  21  and the secondary power supply device  30  are both devices that supply electrical power, yet the electrical power supplied from them are not put in serial or parallel connection and is independently supplied to individual power consuming devices. 
     Referring to  FIGS. 2 and 6 , a block diagram of the present invention is illustrated (see  FIG. 6 ), wherein a slave power supply interface card  10  is provided that comprises a signal connection port  13 , an electrical connection port  11 , a delayed shutdown circuit  14 , and at least one power output port  12 . The signal connection port  13  is set on the power output port  12  to receive, via a signal line  23 , a voltage-on or voltage off signal (Vout≠0/Vout=0) from the computer  20  and the voltage-on/voltage-off signal (Vout≠0/Vout=0) is transmitted to the delayed shutdown circuit  14 . The delayed shutdown circuit  14  sends the signal to the secondary power supply device  30  via the electrical connection port  11 . The electrical connection port  11  is set at an edge of the slave power supply interface card  10  to provide multiple electrical transmissions. The power output port  12  is set on the slave power supply interface card  10  to supply electrical power to peripheral devices  40 . As such, the computer system can obtain additional supply of electrical power for sharing the load of supplying power from the primary power supply device  21  and also realize system expansion so that after the main board  22  is shut down, the peripheral devices  40  can maintain operation for a preset of time period due to the additional supply of electrical power from the secondary power supply device  30 . In this way, the peripheral devices  40  are provided with sufficient time to completely and smoothly shut down, making the computer system more stable and safe. 
     The present invention provides at least the following advantages: 
     (1) The present invention provides a computer system with a secondary power supply device that maintains supplying of power for a preset period of time after the computer system is shut down. In other words, the secondary power supply device itself is shut down in a delayed fashion and during such a delayed period of time, peripheral devices received electrical power from the secondary power supply device stay in a signal silence condition, but still receive sufficient power for a sufficient period of time, whereby the peripheral devices are allowed to smoothly shut down by for example completing storage of data and retracting a magnetic head. In this way, complete and smooth shut down of the peripheral devices is realized and the system is made more stable and safe. 
     (2) In the process of shutdown, the computer performs the operations thereof almost to the maximum extent due to the execution of the shutdown process. Thus, upon completely shutting down, the computer is of a very high temperature. Such a condition, plus the subsequent discharge of capacitors that reach a saturation condition during the shutdown process, which further make heat buildup in the electronic parts of the computer, drives the computer to an even higher temperature. In a conventional computer system that does not adopts the techniques of the present invention, after the shutdown of the computer system, the heat dissipation devices are also stopped for further operation, and consequently, such a high temperature condition may cause damage to the computer system. However, for the present invention, the heat dissipation devices of the computer are maintained in operation for a preset period of time after the computer system is shut down, whereby the high temperature and the buildup of heat can be removed and overcome, and the electronic parts of the computer system can be protected from overheating and burning down. 
     (3) With the primary power supply device and the secondary power supply device being set in a master-slave relationship, upon the booting of a computer system that adopts the techniques of the present invention, the secondary power supply device can be simultaneously started (to supply electrical power to peripheral devices associated therewith) and upon shutting down the computer system, the secondary power supply device carries out a delayed shutdown process (in cutting off power supplied to the peripheral devices associated therewith). In this way, the peripheral devices can be started up or shut down simultaneously with the computer. This provides convenience of the use of the computer system. 
     Although the present invention has been described with reference to the preferred embodiments thereof, it is apparent to those skilled in the art that a variety of modifications and changes may be made without departing from the scope of the present invention which is intended to be defined by the appended claims.