JP2006082400A - Printer - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a printer capable of inexpensively minimizing power consumption and noise of a CPU cooling fan even while properly cooling a CPU. <P>SOLUTION: A memory control ASIC 17 of the printer 10 operates the CPU cooling fan 18 when the CPU 15 is in a normal state. While, the memory control ASIC 17 stops the CPU cooling fan 18 after allowing the operation of the CPU cooling fan 18 to continue for a prescribed period of time when the CPU 15 is shifted from the normal state to a power-saving state. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a printing apparatus.

  As is well known, the processing speed of CPUs of personal computers that are generally available on the market is increasing year by year. As the CPU processing speed increases, the amount of heat generated by the CPU also increases. For this reason, in recent years, personal computers have always provided a CPU cooling fan as a cooling device for cooling the CPU.

  Further, the increase in the processing speed of the CPU is also being realized in the printing apparatus. Therefore, recently, a printing apparatus including a CPU cooling fan is being developed.

  By the way, in the above-described conventional printing apparatus, when the CPU is operating in a so-called power saving state, the power consumption of the CPU is suppressed, so that the heat generation amount of the CPU is also suppressed. Nevertheless, the CPU cooling fan provided in the printing apparatus always operates at a constant rotation while the main power is supplied to the printing apparatus. For this reason, there is a problem that power is wasted by the CPU cooling fan during a period when the CPU is not required to be cooled. In addition, there is a problem that the wind noise of the CPU cooling fan continues to be emitted all the time regardless of whether or not the CPU is not cooled.

  It should be noted that several possible methods for suppressing the power consumption of the CPU cooling fan when the CPU is in a power saving state will be verified.

  First, the start and stop of the operation of the CPU cooling fan is performed by sending a signal instructing the CPU to start or stop power supply to the CPU cooling fan when the main power is turned on or off. This signal is used to output a signal to instruct the CPU to stop supplying power to the CPU cooling fan when the CPU operating state is switched to the power saving state. Is possible to output to the fan power supply circuit. However, in the case of this first method, as shown in FIG. 3, the CPU temperature rises with the stop of the operation of the CPU cooling fan. May be exceeded. Therefore, the first method cannot be adopted.

  Secondly, a method is conceivable in which a temperature sensor is attached to the CPU, and the start and stop of the operation of the CPU cooling fan is switched while the temperature of the CPU is detected by the temperature sensor. However, in the case of the second method, since a temperature sensor is required, it is considered that the cost of the printing apparatus is increased. Therefore, the second method cannot be employed.

  The present invention has been made in view of the above-described conventional problems, and the problem is that the power consumption and noise of the CPU cooling fan can be reduced as much as possible without incurring costs while properly cooling the CPU. It is to suppress.

  A printing apparatus invented to solve the above-described problem is a printing apparatus including a CPU that selectively operates in a normal state and a power saving state, and includes a fan for cooling the CPU, and When the operation state of the CPU becomes the normal state, supply of power to the fan is started, and when the operation state of the CPU is switched from the normal state to the power saving state, a predetermined time from the time of the change. It is characterized by including a fan control unit for stopping the supply of power to the fan after elapse of time.

  In this way, after the CPU changes from the normal state to the power saving state, the fan operation is continued for a predetermined time, and then the fan is stopped, so that the CPU can be properly operated without reaching the upper limit of the operating temperature. It will be cooled down. However, by stopping the fan after the CPU enters the power saving state, power is not consumed by the fan and the wind noise of the fan is stopped.

  Therefore, according to the present invention, it is possible to suppress the power consumption and noise of the CPU cooling fan as much as possible without incurring costs while properly cooling the CPU.

  Hereinafter, one embodiment for carrying out the present invention will be described with reference to the accompanying drawings.

  First, the configuration of a printing apparatus according to an embodiment of the present invention will be described.

  FIG. 1 is a configuration diagram of a printing apparatus 10 according to the present embodiment. The printing apparatus 10 includes a printing engine 11, an image processing ASIC 12, an IO control ASIC 13, a ROM 14, a CPU 15, SDRAM 16, a memory control ASIC 17, a CPU cooling fan 18, and a fan power supply circuit 19 as main components.

  The print engine 11 is a mechanism that actually performs printing on paper. The image processing ASIC 12 is a circuit for performing image processing such as edge enhancement on image data for printing to be supplied to the print engine 11.

  The IO control ASIC 13 controls a host I / F (not shown) which is an interface with a host computer (not shown), an operation panel (not shown) provided on the upper surface of the printing apparatus 10, a ROM 14 and the like. Circuit. The ROM 14 is a non-volatile memory that stores programs executed by the CPU 15, font data used by the CPU 15, and the like.

  The CPU 15 controls each unit in an integrated manner in accordance with a program in the ROM 14, thereby causing the print engine 11 to perform printing in accordance with print data transmitted from a host computer (not shown). It is a control circuit which performs the process which acquires the instruction | indication about the process which should be performed from the user through operation with respect to the operation panel.

  The SDRAM 16 is a memory used for generating data to be supplied to the image processing ASIC 12 based on received print data. The SDRAM 16 is also a memory from which a program to be executed is read from the ROM 14.

  The memory control ASIC 17 is a circuit having a function of controlling the SDRAM 16, a process of storing print data in the SDRAM 16, and a function of executing a data transfer process of supplying data on the SDRAM 16 to the image processing ASIC 12.

  The CPU cooling fan 18 is a device that cools the CPU 15 by sending air toward the cooling fins directly attached to the CPU 15. The fan power supply circuit 19 is a circuit for supplying power to the CPU cooling fan 18.

  Next, the operation of the printing apparatus 10 of this embodiment will be described.

  When the power of the printing apparatus 10 is turned on, the memory control ASIC 17 performs a process of outputting a signal for instructing the start of power supply to the CPU cooling fan 18 to the fan power supply circuit 19 and also executes a program on the ROM 14. A process of loading onto the SDRAM 16 is performed. Thereafter, the CPU 15 performs an initialization process for causing the printing apparatus 10 to operate in the normal mode, and starts an operation in the normal mode. Then, the memory control ASIC 17 determines that “a print request starts to be received by a host I / F (not shown)”, “an operation panel (not shown) is operated”, “without receiving a print request and accepting an operation”. It will be in a state of monitoring the occurrence of three types of events such as “Time passes”.

  Here, when the memory control ASIC 17 detects the occurrence of an event different from the event “a predetermined time has passed without receiving a print request or accepting an operation”, it outputs an interrupt signal to the CPU 15 and outputs this signal. The received CPU 15 executes processing corresponding to the content of the event that has occurred (printing of content in response to a print request or control of an operation panel (not shown)). Thereafter, the memory control ASIC 17 returns to the monitoring state.

  On the other hand, when the memory control ASIC 17 detects the occurrence of an event “a predetermined time has passed without receiving a print request or accepting an operation”, the CPU 15 outputs an interrupt signal to the CPU 15. The operation mode of the printing apparatus 10 is switched to the power saving mode, and its own operation state is switched to the power saving state. It should be noted that the CPU 15 in the power saving state monitors the input of an interrupt signal from the memory control ASIC 17 and stops all processing. At this time, since the power consumption of the CPU 15 is suppressed, the amount of heat generated by the CPU 15 is also reduced compared to the normal state.

  Then, after the operation mode of the printing apparatus 10 is switched to the power saving mode, the memory control ASIC 17 indicates that “a print request starts to be received by a host I / F (not shown)” and “an operation panel (not shown) is operated”. The occurrence of two types of events is monitored. At the same time, the memory control ASIC 17 starts measuring the elapsed time after switching the operation mode in the internal counter (circuit module) 17a. Thereafter, when the memory control ASIC 17 detects that the time on the counter 17a is equal to or greater than a predetermined time indicated by the time information recorded in the internal register (circuit module) 17b, the power to the CPU cooling fan 18 is A process of outputting a signal to stop supply to the fan power supply circuit 19 is performed.

  In this power saving mode, when the memory control ASIC 17 detects the occurrence of an event such as “a print request starts to be received by a host I / F (not shown)” or “an operation panel (not shown) is operated”, the memory control ASIC 17 Then, a process of outputting a signal for instructing the start of power supply to the CPU cooling fan 18 to the fan power supply circuit 19 is performed. At the same time, the memory control ASIC 17 outputs an interrupt signal to the CPU 15 and requests the CPU 15 to start the operation in the normal mode. Upon receiving this request, the CPU 15 returns from the power saving state to the normal state, switches the operation mode of the printing apparatus 10 to the normal mode, and performs processing corresponding to the content of the event that has occurred (printing of content corresponding to the print request or the like). , Control of an operation panel (not shown). Thereafter, the memory control ASIC 17 returns to the monitoring state in the normal mode.

  Next, operations and effects of the printing apparatus 10 according to the present embodiment will be described.

  FIG. 2 is a graph showing a temperature change of the CPU 15 at the time of shifting to the power saving mode in the present embodiment. As described above, the printing apparatus 10 according to the present embodiment switches the operation state of the CPU 15 to the power saving state when the normal mode shifts to the power saving mode, but the CPU 15 stops the operation of the CPU cooling fan 18 when the CPU 15 stops the operation. This is after the predetermined time has elapsed since switching to the power saving state.

  That is, as apparent from a comparison between FIG. 2 and FIG. 3, the CPU cooling fan 18 continues to operate even after the CPU 15 enters the power saving mode and enters the power saving mode. The CPU 15 is cooled without reaching the upper limit (the lower right portion in the graph of FIG. 2). Then, after the CPU 15 is sufficiently cooled, the CPU cooling fan 18 stops, power is not consumed by the CPU cooling fan 18, and the wind noise of the CPU cooling fan 18 stops.

  Therefore, according to the printing apparatus 10 of the present embodiment, the CPU cooling fan 18 can be appropriately cooled without causing the temperature of the CPU 15 to reach the upper limit of the operating temperature, but without the cost of providing a temperature sensor. Power consumption and noise can be suppressed as much as possible.

  It is desirable that the predetermined time indicated by the time information recorded in the register 17b is set to a degree sufficient for the CPU 15 to be cooled. This time information can be set in the register 17b when the power is turned on through software that writes model-specific values such as the system and CPU type in various registers when the power is turned on.

1 is a configuration diagram of a printing apparatus according to an embodiment of the present invention. The graph which shows the temperature change of CPU at the time of power saving mode transfer in this embodiment The graph which shows the temperature change of CPU at the time of power-saving mode transfer in the conventional printing apparatus

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Printing apparatus 11 Print engine 12 Image processing ASIC
13 IO control ASIC
14 ROM
15 CPU
16 SDRAM
17 Memory control ASIC
17a counter 17b register 18 CPU cooling fan 19 fan power supply circuit

Claims (2)

A printing apparatus including a CPU that selectively operates in a normal state and a power saving state,
A fan for cooling the CPU, and
When the operation state of the CPU becomes the normal state, supply of power to the fan is started, and when the operation state of the CPU is switched from the normal state to the power saving state, a predetermined time from the time of switching is determined. A printing apparatus comprising: a fan control unit that stops supplying power to the fan after a lapse of time. A storage unit for storing rewritable time information indicating a certain time;
When the operation state of the CPU is switched from the normal state to the power saving state, the fan control unit, after a certain period of time indicated by the time information stored in the storage unit has elapsed from the time of switching, The printing apparatus according to claim 1, wherein supply of electric power to the fan is stopped.