JP2006159759A - Wireless network printer - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To solve the problem that a wireless network printer in an ad hoc mode is not able to move to be in a low power state in order to always receive a communication request by a radio wave at a place where there are many wireless terminals in the circumference. <P>SOLUTION: Even in the case where a wireless network means receives a communication packet in a low power state, the printer moves from the low power state into a normal state only when a communication key included in the communication packet is matched with a master communication key stored beforehand, and then a CPU means produces the communication response. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a network printer using radio.

  In order to realize power saving while the printer is not used, a shift to a low power state is generally performed. This low power state is to realize low power consumption of the printer by temporarily stopping the operation of some functional blocks inside the printer or reducing the function. Note that the low power state is a general term indicating that the power consumption is lower than the normal state, but in this paper, in particular, in the state where the power supply other than the network interface part is turned off, that is, communication via the network. A state that can have the lowest power consumption in the startable standby state is called a low power state.

  In network printers, a transition to a low power state is performed in order to stand by in a state where power consumption is low. This is when it is detected that a communication request has been received from the network connection destination while reducing power consumption while only the minimum part of the network connection part is energized and no power is supplied to other parts. Respond to the communication by restarting the power supply to the part necessary for communication, and if the communication content is a print operation request, restart the power supply to the part necessary for the print operation and start the print operation It is a mechanism to do.

  However, some devices on the network periodically send broadcast packets or communications addressed to the IP address of the printer in order to check the existence of the connected devices, and such devices are connected to the network. In this case, since a communication request is periodically sent to the printer connected to the network, the part necessary for the printer communication is immediately updated even when the printer is switched to the low power state. It is necessary to return to a normal state in which communication is possible for communication, and even if a printing operation is not performed, the communication part cannot be substantially maintained in a low power state, and is shifted to a low power state. The effect of reducing power consumption is diminished.

In order to avoid this, when in a low power state, it reacts only when a special packet including a MAC address that is a unique number for the network interface is received, and then returns to a normal state in which communication can be performed from the low power state. Has been proposed (see, for example, Patent Document 1).
USP 583519

  However, in the above-described method using a special packet including a MAC address that is a unique number for the network interface, the MAC address unique to the printer must be registered in advance for the number of printers in the host computer that communicates with the printer. Due to the restriction that it must be used, it will be used in a network where connected devices such as offices are closed, and in a public network where many unspecified devices may be connected, the printer can not be restored from the low power state Because it is difficult to use.

  In addition, when using a wireless network that is now widely used, in addition to simply replacing the conventional star network by wire with a wireless network, a pair called an ad hoc mode in which each wireless network device is connected one-to-one. One type of connection is possible, and the printer can communicate directly with an unspecified number of devices. In this ad-hoc mode connection, there is provided a mechanism for selecting a device that really needs to be communicated from an unspecified number and reacting only to communication from the selected device to return from the low power state to the normal state. Therefore, there is a problem that the wireless network printer in the ad hoc mode cannot shift to the low power state in order to always receive a communication request by radio waves in a place where there are many wireless terminals in the vicinity.

  Generally, a printer is in a standby state for a longer time than an operating state, and the power consumption in the standby state is dominant with respect to the power consumption. Therefore, the power consumption of the printer greatly increases due to the above-described problem.

  In order to solve the above-described problem, the wireless network printer according to claim 1 includes wireless network means, power management means, printing means, and CPU means, and the power of the wireless network means and the CPU means is on. There are at least two power states, a normal state and a low power state in which the power of the wireless network means is on and the power of the CPU is off, and the two power states are switched under the control of the power management means In the low power state, even when the wireless network means receives a communication packet, only when the communication key included in the communication packet matches the master communication key stored in advance The state transitions from the low power state to the normal state and the CPU means And performing a response.

  Further, the wireless network printer according to claim 2 is the network printer according to claim 1, wherein the master communication key is not unique or confidential to the individual network printer, and is a general and publicly known function representing a print function. It is a characteristic.

  According to the wireless network printers of the first and second aspects of the present invention, in the connection in the ad hoc mode in which the wireless network devices are connected one-to-one, the printer can perform a number of unspecified devices that can directly communicate with each other. It is possible to return to the normal state from the low power state by reacting only to communication from devices that really need communication, and always receive communication requests by radio waves in places where there are many wireless terminals around Even in this case, the power consumption reduction effect due to the transition to the low power state can be maximized without wastefully returning from the low power state to the normal state.

Example 1
An embodiment of a wireless network printer according to claim 1 of the present invention will be described below with reference to the drawings.

  FIG. 1 is a schematic diagram showing the presence of a wireless network printer and peripheral wireless network devices according to the present embodiment. 1 is a wireless network printer, 2 is a wireless network scanner, 3 is a wireless network camera, 4 is a wireless network mobile phone, 5 is a wireless network computer, 6 is a wireless network vehicle, and 7 is another wireless network device. It is. The wireless network printer can wirelessly communicate with surrounding wireless network devices.

  FIG. 2 is a block diagram showing the internal configuration of the wireless network computer 5 according to the present embodiment. In the figure, 11 is a computer wireless network interface unit, and 12 is a computer core unit. The computer core unit 12 can communicate with other wireless network devices via the computer wireless network interface unit 11.

  FIG. 3 is a block diagram showing an internal configuration of a computer core unit in the wireless network computer in the image forming system according to the present embodiment. In the figure, 13 is a computer control LSI, 14 is a computer memory, and 15 is a computer HDD. The computer control LSI 13 operates in accordance with the program contents stored in advance in the computer HDD 15. At this time, the computer control LSI 13 uses the computer memory 14 and the computer HDD 15 as a work area and a storage area.

  FIG. 4 is a block diagram showing the internal configuration of the wireless network printer in the image forming system according to the present embodiment. In the figure, 21 is a printer wireless network interface unit, 22 is a printer core unit, 23 is a printer print processing unit, and 24 is a printer power supply control unit. The printer core unit 22 can communicate with other wireless network devices via the printer wireless network interface unit 21. The printer core unit 22 transmits a control command and image data to be printed to the printer print processing unit 23, and the printer print processing unit 23 can print out the image data. The printer power supply control unit 24 monitors the operation status of the printer core unit 22 and the printer print processing unit 23, and the power supply of the printer core unit 22 and the printer print processing unit 23 when the operation has not been performed for a certain period of time. When the printer is in the low power state, the printer power supply control unit 24 monitors the operation status of the printer wireless network interface unit 21 and turns it off via the wireless network. When communication related to the printing operation is performed, the printer core unit 22 and the printer print processing unit 23 are turned on to return the printer to the normal state. Details of this operation will be described later.

  FIG. 5 is a block diagram showing an internal configuration of a printer core unit in the wireless network printer in the image forming system according to the present embodiment. In the figure, 25 is a printer control LSI, 26 is a printer memory, and 27 is a printer HDD. The printer control LSI 25 operates according to the program contents stored in advance in the printer HDD 27. At this time, the printer control LSI 25 uses the printer memory 26 and the printer HDD 27 as a work area and a storage area.

  FIG. 6 is a schematic diagram of a header portion of a wireless packet transmitted to the wireless network printer in the image forming system according to the present embodiment. 31 is a communication key. This header is a header of a TCP packet, and a communication key is mounted using an option area. The wireless network printer refers to and compares the communication key 31 of the received communication packet to determine whether the communication is related to the printing operation. Details of this procedure will be described later.

  FIG. 7 shows master communication keys stored in the printer wireless network interface unit 21 of the wireless network printer in the image forming system according to the present embodiment. The printer wireless network interface unit 21 compares the communication key of the received wireless communication packet header with the master communication key to determine whether the communication packet is related to the printing operation. This master communication key is stored in advance when the wireless network printer is manufactured, and this master communication key is also stored in advance in a communication device incorporating software for requesting printing such as a printer driver, and a communication packet header for the printer. The master communication key is inserted into the communication key and transmitted.

  Next, the part of the wireless network printer corresponding to each means in claims 1 and 2 will be described. The wireless network means is the printer wireless network interface unit 21. The power management means is the printer power supply control unit 24. The printing means is the printer print processing unit 23. The CPU means is the printer core unit 22.

  The operation of the wireless network printer with the above configuration will be described below. When the wireless network printer is in a low power state, receiving a wireless communication request from a nearby wireless network device does not cancel the low power state and receives a print operation request from a wireless network computer via wireless communication Then, an example is to cancel the low power state and start the printing operation. Here, the wireless network printer is in a low power state, the power supply of the printer core unit 22 and the printer print processing unit 23 inside the wireless network printer is turned off, and only the printer wireless network interface unit 21 and the printer power supply control unit 24 are turned off. Is turned on.

  First, an operation when a communication request packet is received from a peripheral wireless network device when the wireless network computer is in a low power state will be described. As shown in FIG. 1, there are various wireless network devices around the wireless network computer, and they are in a state of issuing a wireless communication request. Communication packets are received one after another.

  First, the wireless network scanner 2 performs broadcast wireless communication in order to search for surrounding wireless network mobile phones. The wireless network mobile phone 4 responds to this by unicast wireless communication. Here, broadcast refers to communication with all wireless network devices to be received, and unicast refers to communication with respect to a specific wireless network device specified by an IP address. Since the printer network interface unit 21 in the wireless network printer receives the latter unicast communication, the IP address of the communication destination is that of the wireless network scanner 2 and is not addressed to itself. Although this is ignored and discarded according to the protocol, if the former broadcast communication is received, it is determined whether this communication is related to the wireless network printer. Specifically, the value of the communication key in the header portion of the wireless packet at this time is read and compared with the master communication key stored in the printer wireless network interface unit. FIG. 8 shows a communication key of a communication packet header transmitted by the wireless network scanner 2. As described above, the printer wireless network interface unit 21 compares the communication key with the master communication key, and determines that it is not a communication packet related to the printing operation because it does not match. To maintain.

  Next, the wireless network computer 5 performs broadcast wireless communication in order to search for surrounding wireless network cameras. The wireless network camera 3 responds to this by unicast wireless communication. Also in this case, as in the case of communication between the wireless network mobile phone 4 and the wireless network scanner 2, when the former broadcast communication is received, it is determined whether or not this communication is related to the wireless network printer. Specifically, the value of the communication key in the header portion of the wireless packet at this time is read and compared with the master communication key stored in the printer wireless network interface unit. FIG. 9 shows a communication key of a communication packet header transmitted by the wireless network computer 5. As described above, the printer wireless network interface unit 21 compares the communication key with the master communication key, and determines that it is not a communication packet related to the printing operation because it does not match. To maintain.

  Next, the wireless network computer 5 performs broadcast wireless communication in order to search for surrounding wireless network printers. At this time, the wireless network computer 5 transmits the master communication key, which means a printing operation, using the communication key of the communication packet header. When the wireless network printer 1 receives the broadcast communication, the wireless network printer 1 determines whether the communication is related to the wireless network printer. Specifically, the value of the communication key in the header portion of the wireless packet at this time is read and compared with the master communication key stored in the printer wireless network interface unit. The communication key of the communication packet header transmitted by the wireless network computer 5 is a master communication key. As described above, the printer wireless network interface unit 21 compares the communication key with the master communication key, and determines that the communication packet is related to the printing operation because they match. Then, the printer wireless network interface unit 21 tries to transmit a communication packet to the printer core unit 22. Here, as described above, when the printer is in the low power state, the printer power supply control unit 24 monitors the operation status of the printer wireless network interface unit 21, and communication related to the printing operation is performed via the wireless network. When the printer core unit 22 is turned on, the printer core unit 22 is returned to the normal state. The printer wireless network interface unit 21 transmits a communication packet to the printer core unit 22 that has returned to the normal state. The printer core unit 22 creates a response communication packet under the control of the printer control LSI 25, and the printer wireless network interface unit 21. Is transmitted to the wireless network computer 5 via. The wireless network computer 5 receives communication from the wireless network printer 1, confirms that printing is possible, and starts communication for a print operation request. The wireless network printer 1 receives communication for a print operation request. The printer power supply control unit 24 monitors the operation status of the printer wireless network interface unit 21, detects that a print operation request has been communicated via the wireless network, and turns on the printer print processing unit 23. The printer print processing unit 23 is returned to the normal state. The returning operation of the printer print processing unit 23 takes time to heat a fixing device (not shown), and the fixing device is heated to a predetermined temperature and then shifts to a normal state. After the printer print processing unit 23 shifts to the normal state, the printer print processing unit 23 performs a print operation on the print request signal received via the printer wireless network interface unit 21 under the control of the printer core unit 22. After the printing operation, the printer core unit 22 and the printer print processing unit 23 of the wireless network printer 1 shift to a low power state under the control of the printer power supply control unit 24.

  Next, the wireless network vehicle 6 performs broadcast wireless communication in order to indicate presence in the surroundings. Further, the other wireless network device 7 performs broadcast wireless communication in order to transmit information to surrounding wireless terminals. When the wireless network printer 1 receives the broadcast communication, the wireless network printer 1 determines whether the communication is related to the wireless network printer. Specifically, the value of the communication key in the header portion of the wireless packet at this time is read and compared with the master communication key stored in the printer wireless network interface unit. FIGS. 10 and 11 are communication keys of communication packet headers transmitted by the wireless network vehicle 6 and other wireless network devices 7, respectively. As described above, the printer wireless network interface unit 21 compares the communication key with the master communication key, and determines that it is not a communication packet related to the printing operation because it does not match. To maintain.

  FIG. 12 is a graph of fluctuations in the power consumption value of the wireless network printer in the above procedure. In the low power state, the power supply of the printer core unit 22 and the printer print processing unit 23 inside the wireless network printer is off, and only the printer wireless network interface unit 21 and the printer power supply control unit 24 that do not have a drive unit or CPU are turned on. Therefore, power consumption is very low. As described above, even when communication with the wireless network printer 1 is received, whether or not the communication content is related to the printing operation is determined by the communication key of the packet header, so that the printer core unit 22 can perform the communication with respect to irrelevant communication. The low power state can be maintained by not turning on the power.

  FIG. 13 is a graph of fluctuations in the power consumption value of the conventional wireless network printer in the above procedure. The wireless network printer according to the prior art here shifts from the low power state to the normal state in order to make a response by the printer core unit 22 for wireless communication not related to the printing operation. For this reason, when there are many wireless network devices in the vicinity as in the present embodiment, as shown in the figure, the time for shifting to the low power state is very short, and most of the operation time is in the normal state. It consumes a lot of power.

  As described above, the wireless network printer using the communication key of the present invention can maintain the low power state even when there are many wireless network devices in the vicinity, and can realize low power consumption. In general, the printer device and the printer driver software are created by the same manufacturer. Therefore, as shown in this embodiment, the master communication key can be determined in advance and embedded in each product. It is. If determined as an industry standard, it is also possible to communicate with a wireless network printer from printer driver software of a different manufacturer. Furthermore, by setting the master communication key of the wireless network printer separately, it can be operated so that it returns from the low power state to the normal state only during wireless communication from a device that knows the communication key. Is possible. In this case, if the wireless network printer is in a normal state and once the operation related to printing is performed to notify the printer driver software of the master communication key, the printer driver software that has communicated once Recovery from a low power state can be performed only from Or, in combination with a device using another authentication, the master communication key is notified when the authentication is performed, so that the recovery from the low power state can be performed only from the authenticated printer driver software. .

It is a schematic diagram which shows presence of the wireless network printer and peripheral wireless network apparatus which concern on this Embodiment. It is a block diagram which shows the internal structure of the wireless network computer 5 which concerns on this Embodiment. 2 is a block diagram showing an internal configuration of a computer core unit in a wireless network computer in the image forming system according to the present embodiment. FIG. 2 is a block diagram showing an internal configuration of a wireless network printer in the image forming system according to the present embodiment. FIG. 2 is a block diagram illustrating an internal configuration of a printer core unit in a wireless network printer in the image forming system according to the present embodiment. FIG. 4 is a schematic diagram of a header portion of a wireless packet transmitted to a wireless network printer in the image forming system according to the present embodiment. FIG. This is a master communication key stored in the printer wireless network interface unit 21 of the wireless network printer in the image forming system according to the present embodiment. This is a communication key of a communication packet header transmitted by the wireless network scanner 2. This is a communication key of a communication packet header transmitted by the wireless network computer 5. This is a communication key of a communication packet header transmitted by the wireless network automobile 6. This is a communication key of a communication packet header transmitted by another wireless network device 7. 6 is a graph of fluctuations in the power consumption value of the wireless network printer in the procedure described in the first embodiment. 6 is a graph of fluctuations in power consumption values of a wireless network printer according to a conventional technique in the procedure described in the first embodiment.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Wireless network printer 2 Wireless network scanner 3 Wireless network camera 4 Wireless network mobile phone 5 Wireless network computer 6 Wireless network vehicle 7 Other wireless network equipment 11 Computer wireless network interface part 12 Computer core part 13 Computer control LSI
14 Computer memory 15 Computer HDD
21 Printer Wireless Network Interface Unit 22 Printer Core Unit 23 Printer Print Processing Unit 24 Printer Power Supply Control Unit 25 Printer Control LSI
26 Printer Memory 27 Printer HDD
31 Communication key

Claims (2)

  A wireless network means, a power management means, a printing means, and a CPU means, wherein the power of the wireless network means and the CPU means is on, and the power of the wireless network means is on and the power of the CPU is off A network printer that has at least two power states, i.e., a low power state, and is capable of switching between the two power states under the control of the power management means. When in the low power state, the wireless network means Even when the communication packet is received, only when the communication key included in the communication packet matches the master communication key stored in advance, the state is shifted from the low power state to the normal state, and communication by the CPU means is performed. It is characterized by making a response.   2. The network printer according to claim 1, wherein the master communication key is not unique or confidential to a network printer individual but is a general and well-known one representing a print function.

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