JPH10293661A - Network printer system - Google Patents

Abstract

(57) [Problem] To provide a network printer system capable of recognizing a printing state of a printer on a computer side and enabling printing on an alternative printer or a printer after recovery from a failure even if a failure occurs in a printer to be printed. provide. A computer for transmitting print data, a printer engine, a controller for controlling the printer engine, a printer queue table for storing a print request transmitted from the computer, and a response signal to a print request from the computer. Communication department to reply
In a network printer system including a printer having a printer 102 and a network connecting the computer and the printer, the computer transmits a print status signal transmitted from the communication unit 102 of the printer via the network and indicating a print status of the printer. The printing status of the printer is ascertained based on the printing status.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a network printer system in which a plurality of print data output devices such as computers and workstations and an image forming device such as a laser printer are connected via a network.

[0002]

2. Description of the Related Art Various network printer systems have been proposed in which a plurality of print data output devices such as computers and workstations and image forming devices such as laser printers are connected via a network such as a LAN. For example, Japanese Patent Application Laid-Open No. Hei 5-289833 discloses a network print control system in which a plurality of data processing devices and at least one printer are connected on a transmission medium. A data transmission / reception unit connected to the transmission medium via the interface, for transmitting / receiving data, analyzing a command received by the transmission / reception unit, and storing the data in a print queue corresponding to the printer recognized according to the analyzed command. A reception processing unit for queuing the management information of the data and storing the print file of the data, and a process for transmitting the management information and the print file queued in the print queue; Sending that supports Comprising a processing unit, the gateway comprising a cancellation of the print at this gateway, broadcast print, sorting etc. in the event of a failure performed.

[0003] Japanese Patent Application Laid-Open No. Hei 5-341928 discloses a communication system between a host computer and a printer connected to the host computer via an interface. After sending a printer information inquiry code for inquiring the printer of printer specific information,
The printer sets the busy signal to a busy state, sets the busy signal to a ready state at a timing at which the printer information inquiry code can be received again, and based on a time interval from busy to ready at this time, the printer information inquiry is thereafter performed. A busy signal is controlled at a time interval corresponding to the code, and the host computer detects the length of the busy signal, thereby transmitting printer-specific information from the printer to the host computer. The host computer can automatically inquire about the printer type and setting values.

Japanese Patent Application Laid-Open No. Hei 7-281850 discloses a printer which aims to transfer received print information to a destination printing apparatus designated by a printing apparatus in which a printing failure has occurred and to perform alternative printing. An alternative printing method for the system and the printer system is disclosed. During printing by the printer engine, each piece of information is detected from each state detecting unit, and the control device determines a print failure occurrence state. In this case, the print information received from the data supply source is transferred to another printing device on the network that performs alternative printing, based on the designated transfer destination information that is designated and input and stored.

Japanese Patent Application Laid-Open No. Hei 8-222234 discloses a printer sharing system in which a plurality of networks each having a plurality of workstations using different types of network operation systems and a printer shared by the respective workstations are used. A network system is disclosed. In this printer sharing network system, a printer status management device that collectively manages a different status for each operation system of the printer of each network is provided, and connected to networks of different types of network operation systems. Multiple printers can be managed collectively. Further, the printer status management device is provided with means for notifying a workstation using the printer or a previously registered workstation of error information when an error status is received as the status of the printer.

[0006]

Problems to be Solved by the Invention
No. 3 network print control system,
In the printer sharing network system described in Japanese Patent Application Laid-Open No. Hei 8-222234, a gateway and a printer status management device are provided in the network, and the gateway and the printer status management device manage the connection between the host computer and the workstation and the printer. However, the host computer and the workstation are not involved in these. For this reason, information such as printing status is not directly transmitted and received between the host computer or workstation and the printer, and the status cannot be recognized on the host computer or workstation side in the event of a printer failure. There is a problem that it takes a long time to perform processing such as switching, and also that there is a problem that the cost is increased because a gateway and a printer status management device are provided on the network.

In the printer information inquiry communication system described in Japanese Patent Application Laid-Open No. Hei 5-34128, a printer type and a set value can be automatically inquired from a host computer. , Nothing is described.

In the printer system and the alternative printing method of the printer system described in JP-A-7-281850, a print failure occurrence state is determined, and when the print failure occurrence state is determined, the print failure is designated and stored. By transferring the print information received from the data source based on the designated transfer destination information to another printing device on the network that performs alternative printing, the printing device in which the printing failure has occurred is designated and designated as the designated transfer destination printing device. The print information received by the printer can be transferred to perform alternative printing. However, a transfer device such as a DMA for designating the alternative printing device and transferring it to the alternative printing device is required in the printing device. Take it.

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and does not require a special server such as a gateway or a printer status management device on a network. Recognizes the printing status of the image forming device, and enables printing on an alternative image forming device or an image forming device after recovery from a fault, even if a fault such as paper jam or running out of toner occurs in the image forming device to be printed. It is an object of the present invention to provide a network printer system.

[0010]

According to a first aspect of the present invention, there is provided a print data output device for transmitting print data, an image forming unit, a control unit for controlling the image forming unit, and a control unit for controlling the image forming unit. An image forming apparatus comprising: a printer queue table that stores a print request transmitted from a print data output device; and a communication unit that returns a response signal to the print request from the print data output device.
In a network printer system comprising the print data output device and a network connecting the image forming device, the print data output device is configured to transmit a print of the image forming device transmitted from a communication unit of the image forming device via a network. Based on the print status signal indicating the status,
The printing condition of the image forming apparatus is ascertained.

According to a second aspect of the present invention, in the network printer system according to the first aspect, the image forming apparatus returns a printable response signal in response to a printable print request from the print data output device, and performs printing. At the time when execution of the print data becomes possible, sending a print data request to the print data output device, receiving and outputting the print data, and sending a print end to the print data output device when the printing is completed. .

According to a third aspect of the present invention, in the network printer system according to the first aspect, the image forming apparatus returns a printable response signal to a printable print request from the print data output device, and performs printing. Is executed, a print data request is issued to the print data output device, print data is received and output, and a print status signal is sent periodically.

According to a fourth aspect of the present invention, in the network printer system according to the first aspect, the image forming apparatus returns a printable response signal in response to a printable print request from the print data output device, and performs printing. Sending a print data request to the print data output device, receiving and outputting print data, and sending a print status signal in response to a print status confirmation request from the print data output device when the execution of the print data is enabled. And

The invention according to claim 5 is the invention according to claim 3 or 4.
In the network printer system described above, the image forming apparatus notifies the print data output device of the content of the failure when a failure occurs.

According to a sixth aspect of the present invention, in the network printer system according to the fifth aspect, when a notification of a failure content is received from the image forming apparatus, the print data output apparatus returns a response. , An alternative image forming apparatus is designated.

According to a seventh aspect of the present invention, in the network printer system according to the fifth aspect, when a notification of a failure content is received from the image forming apparatus, the print data output apparatus selects an alternative image forming apparatus. It is characterized in that it is possible to specify whether to re-execute on the image forming apparatus in which a failure has occurred.

The invention according to claim 8 is the invention according to claim 3 or 4.
In the network printer system described above, the image forming apparatus includes a storage unit that stores print data, holds the print data until printing is completed, and when a failure occurs, does not accept a print request during the failure, and after a failure recovery operation, It is characterized in that print data being printed at the time of occurrence of a failure is taken out of the storage means and printed.

According to a ninth aspect of the present invention, in the network printer system according to the eighth aspect, it is possible to specify an output page of the print data after the failure recovery work.

[0019]

DESCRIPTION OF THE PREFERRED EMBODIMENTS A network printer system according to the present invention comprises a plurality of print data output devices, an image forming device,
For example, a computer and a printer (such as a laser printer) are connected via a network. And
Even when a failure such as paper jam or running out of toner occurs in a printer to be printed, printing can be performed by a substitute printer or a printer after a failure recovery operation.

In the network printer system of the present invention, a printer queue table and communication means are provided on the printer, and a response is returned to a printable print request from a computer if printing is possible. When the printer is ready for printing, it issues a print data request to the computer, and the computer receiving the print data request sends the print data to the printer that sent the request. Then, the printer sends a print end to the computer when printing is completed. However, when a failure occurs in the printer, a print data request or a print end is not sent to the computer. Therefore, by monitoring the print data request from the printer or the end of printing, the computer can determine whether or not a failure has occurred in the printer, and can take measures such as switching to an alternative printer. If there are a plurality of printers that have returned a response, the print data is sent to the printer that first issued the print data request.

As described above, a print data request is issued from the printer at the start of printing, and a print end is sent to the computer at the end of printing. It can be recognized, and a print request can be issued to another printer when a failure occurs. Therefore, in the present invention, it is not necessary to have information on the substitute printer on the printer, nor is it necessary to have a transfer means to the substitute printer. Also, there is no need to provide a special server on the network. Hereinafter, the configuration and operation of the present invention will be described in detail based on embodiments.

(Embodiment 1) FIG. 1 shows a configuration example of a printer of a network printer system according to the first and second aspects. The printer includes a printer queue table 101 for storing print requests, a network communication unit 102, a controller 103 for controlling the printer, and a printer engine 104 for printing print data. A plurality of printers having such a configuration and a plurality of computers (or workstations or the like, not shown) are connected via a network. The print request received from the computer is stored in the printer queue table 101. Print data requests are sent to the computer in the order in which they were stored,
The print data sent from the computer in response to the print data request is sent to the printer engine 10 by the controller 103.
It is sent to 4 and printed.

Next, the operation at the time of printing will be described. FIG.
FIG. 7 is a diagram showing an example of an operation procedure of a computer and a printer when printing is performed by the network printer system. First, a computer to be printed issues a print request 201 on the network. This print request includes information such as the format of print data and paper size, and is issued to all printers on the network. Here, the data format of the print request is shown in FIG. In FIG. 3, the requesting computer 301 is the host name on the network that issued the print request, and the data ID 302 is the ID and print data format uniquely determined for the print data on the requesting computer.
A print data format 303 is text data and PostScript data, a paper size 304 is a paper size A4 and A3, and a data size 305 is the size of print data to be transferred.

Upon receiving the print information of the print request 201, the printer analyzes the data such as the format of the print data and the paper size 202, and returns a response 203 including the printer name to the computer if the data can be printed. I do. FIG. 4 shows the data format of the response signal. In FIG. 4, a printer name 401 is a printer name on the network and has a data ID.
402 is the same as the data ID 302 that received the print request.

When the computer 203 that has issued the print request 201 does not return a response 203 even after waiting for a certain period of time, it is determined that there is no printer capable of printing on the network, so that a print error occurs. When the printer enters the printable state 204, it sends a print data request 205 to the computer. The computer receiving the print data request 205 prints the print data request 2
Send print data 206 to the printer that sent 05. If the print data request has not been sent for a certain period of time, a print request 201 is issued again. The printer starts printing 207 when the printing data 206 is transferred, and returns a printing completion status 208 which is one of the printing status signals when printing is completed. Upon receiving the print end status 208, the computer discards the print data 209. When a failure occurs in the printer, the printer does not return a print end status. Therefore, the computer recognizes that the printer has failed and the computer issues a print request again.
Give 1

As described above, if the computer monitors whether the response 203 or the print data request 205 from the printer is returned within a certain period of time (for example, 30 seconds to 1 minute), the failure of the printer can be prevented. You can recognize if there was. If the print end status 208 is not returned for a certain period of time (for example, 30 seconds to 1 minute), it means that a failure has occurred in the printer, and the computer returns to the print request 201 again.
Put out. As described above, when a failure occurs in a printer, the computer repeats the process from the print request 201, thereby enabling printing by another printer on the network.

(Embodiment 2) FIG. 5 shows a configuration example of a printer of a network printer system according to the first and third aspects. The printer includes a printer queue table 501 for storing a print request, a network communication unit 502, a controller 503 for controlling the printer, and a printer engine 504 for printing print data. A plurality of printers having such a configuration and a plurality of computers (not shown) are connected via a network. The print request received from the computer is stored in the printer queue table 501. Print data requests are sent to the computer in the order in which they are stored, and print data sent from the computer in response to the print data request is sent to the printer engine 504 by the controller 503 for printing.

Next, the operation at the time of printing will be described. FIG.
FIG. 7 is a diagram showing an example of an operation procedure of a computer and a printer when printing is performed by the network printer system. First, a computer to be printed issues a print request 601 on the network. This print request includes information such as the format of print data and paper size, and is issued to all printers on the network. The data format of the print request is the same as that of the first embodiment, and is the format as shown in FIG.

The printer which has received the print information of the print request 601 analyzes the data such as the format of the print data and the paper size, and returns a response 603 including the printer name to the computer if the data can be printed. I do. The data format of the response signal is the same as that of the first embodiment, and is the format as shown in FIG.

If the computer that has issued the print request 601 does not return a response 603 even after waiting for a certain period of time, it is determined that there is no printer capable of printing on the network, so that a print error occurs. When the printer enters the printable state 604, a print data request 605 is sent to the computer. The computer receiving the print data request 605 requests the print data.
The print data 606 is sent to the printer that sent 605. If the print data request has not been sent for a certain period of time, a print request 601 is issued again. Computer print data 606
For a certain period of time (for example, 30 seconds to 1
Minutes) Wait for the print status (print status signal) from the printer. As the printing status, the printer returns a printing status 607 if printing is in progress, and a printing end status 608 if printing is completed. Print end status 608
When the computer receives 609, the computer discards the print data. If a failure occurs in the printer, the printer does not return a print status. Therefore, the computer recognizes that a failure has occurred in the printer, and the computer issues a print request 601 again.

As described above, the computer can monitor whether the response 603 from the printer to the print request 601 or the print data request 605 is returned within a predetermined time (for example, 30 seconds to 1 minute). It is possible to recognize whether or not the printer has failed. In addition, trouble occurrence during printing
If the printer does not return a print status for a certain period of time (for example, 30 seconds to 1 minute) after the transfer of the print data 606, the computer issues a print request 601 again because a failure has occurred. Thus, when a failure occurs, the print request 60
Repeating from 1 enables printing on another printer on the network. Further, the occurrence of a failure during printing can be recognized by not returning the printing status for a certain period of time after the transfer of the printing data.
It is possible to shorten the response waiting time.

(Embodiment 3) FIG. 7 shows a configuration example of a printer of a network printer system according to the first and fourth aspects. The printer includes a printer queue table 701 for storing a print request, a network communication unit 702, a controller 703 for controlling the printer, and a printer engine 704 for printing print data. A plurality of printers having such a configuration and a plurality of computers (not shown) are connected via a network. The print request received from the computer is stored in the printer queue table 701. Print data requests are sent to the computer in the order in which they are stored, and print data sent from the computer in response to the print data request is sent to the printer engine 504 by the controller 503 for printing.

Next, the operation at the time of printing will be described. FIG.
FIG. 7 is a diagram showing an example of an operation procedure of a computer and a printer when printing is performed by the network printer system. First, a computer to be printed issues a print request 801 on the network. This print request includes information such as the format of print data and paper size, and is issued to all printers on the network. The data format of the print request is the same as that of the first embodiment, and is the format as shown in FIG.

The printer which has received the print information of the print request 801 analyzes the data such as the format of the print data and the paper size 802 and returns a response 803 including the printer name to the computer if the data can be printed. I do. The data format of the response signal is the same as that of the first embodiment, and is the format as shown in FIG.

If the computer which has issued the print request 801 does not return a response 803 after waiting for a predetermined time (for example, 30 seconds to 1 minute), it is determined that there is no printer capable of printing on the network, so that a print error is generated. When the printer enters the printable state 804, a print data request 805 is sent to the computer. The computer that has received the print data request 805 sends the print data 806 to the printer that has sent the print data request 805. A fixed time (for example, 30 seconds to 1
Minutes) If a print data request is not sent, a print request 801 is issued again. The computer issues a printer status request 807 when the transfer of the print data 806 is completed. In response to the printer status request 807, the printer returns a printing status 808 if printing is in progress, and returns a printing end status 809 if printing is completed. Print end status
Upon receiving 809, the computer discards the print data.
I do. The printer does not return a status when a failure occurs. Therefore, if the status is not returned for a certain period of time (for example, 30 seconds to 1 minute), it means that a failure has occurred in the printer, and the computer issues a print request 801 again.

As described above, if the computer monitors the response 803 from the printer to the print request 801 and the print data request 805 within a certain period of time, it is possible to determine whether the printer has failed. Can be recognized. In addition, the failure during printing means that if the printer does not return the print status 808 or the print end status 809 in response to the printer status request 807 after the transfer of the print data 806, it means that the failure has occurred, and the computer will print again. Issue request 801. In this way, when a failure occurs, printing can be performed by another printer by repeating the process from the print request 801. Further, the occurrence of a trouble during printing can be recognized by confirming the response of the printing status to the printer status request 807 after the transfer of the print data. It is not necessary to adjust the waiting time.

(Embodiment 4) A network printer system according to claim 5 will be described. In this embodiment, in addition to the configuration of any one of the second and third embodiments, when a printer failure occurs, the computer is notified of the content of the failure. Here, as an example, the basic configuration of the network printer system is the same as that of the third embodiment. FIG. 9 is a diagram showing an example of an operation procedure of the computer and the printer when printing is performed by the network printer system according to claim 5, and is an example including a procedure for notifying the details of a failure when a failure occurs. In FIG. 9, operations from a print request 901 to a printer status request 907 are the same as those in the third embodiment.
In response to a printer status request 907 from the computer, when a failure such as a jam 909 occurs on the printer side, a signal notifying the details of the failure is sent to the computer. The format of the data sent at this time is as shown in FIG. 10, where the printer name 1001 is the name of the printer on the network, the data ID 1002 is the data ID of the print data,
Are obstacles such as jam, running out of toner and running out of paper. The computer receiving the failure notification from the printer issues a print request 901.
Start over. As described above, in the network printer system according to the present embodiment, it is possible to take various measures for recovery from a failure by notifying the computer of the content of the failure.

(Embodiment 5) A network printer system according to claim 6 will be described. In the present embodiment, in addition to the configuration of the fourth embodiment, the computer which has received the notification of the failure content from the printer selects an alternative printer. FIG. 11 is a flowchart showing the operation of the computer from receiving a response after a print request to selecting an alternative printer when a failure occurs. When an alternative printer exists on the network, responses to the print request are returned from the plurality of printers. Response data (similar to the data format of FIG. 4) returned from a plurality of printers is arranged on a computer and managed as a list. Then, the printer which first returns the print data request is deleted from the list, the print data is transferred to the printer, and the printing operation is performed. If an error occurs in the printer during printing, the occurrence of the error is displayed (error display), all the printers in the list are displayed, the next printer is selected from the list, and a print request is issued to the printer. . As described above, in the network printer system according to the present embodiment, when a failure occurs in a printer, the computer that has been notified of the details of the failure selects an alternative printer.

(Embodiment 6) A network printer system according to claim 7 will be described. In the present embodiment, in addition to the configuration of the fourth embodiment, it is possible to specify whether to select an alternative printer on the side of the computer that has been notified of the content of the failure from the printer or to re-execute the printer on which the failure has occurred. It was made. FIG. 12 is a flowchart showing the operation of the computer from the reception of a response after a print request to the selection of an alternative printer in the event of a failure or the designation of re-execution in the printer in which a failure has occurred. If a failure occurs during printing, a notification of the content of the failure is sent from the printer. At this time, the computer selects whether or not to re-execute when a failure occurs. The re-execution may be performed after receiving the notification of the failure repair from the printer side. However, in the procedure shown in the figure, the re-execution is performed based on the judgment of the user side. Also, if you have an alternative printer and do not try again,
As in the fifth embodiment, an alternative printer is selected, and a print request is issued to the selected printer. As described above, in the network printer system according to the present embodiment, when a failure occurs in a printer, it is possible to specify whether the computer receiving the notification of the failure selects an alternative printer or specifies whether to re-execute on the failed printer. Since the alternative printer can be used, it is possible to cope with a case where an alternative printer cannot be used.

(Embodiment 7) FIG. 13 shows a configuration example of a printer of a network printer system according to claim 8.
The printer includes a printer queue table 1301 for storing print requests, a network communication unit 1302, a controller 1303 for controlling the printer, a printer engine 1304 for printing print data, and a storage device 13 for storing received print data.
It consists of 05. A plurality of printers having such a configuration and a plurality of computers (not shown) are connected via a network. The print requests received from the computer are stored in the printer queue table 1301, and the print data requests are sent to the computer in the order stored,
The print data sent from the computer in response to the print data request is sent to the printer engine 13 by the controller 1303.
It is sent to 04 and printed. At this time, the print data is printed and stored in the storage device 1305 at the same time. When a failure occurs during printing, print data is stored in the storage device 1305 once. At this time, even if a new print request comes, a printable response is not returned. Therefore, a new print request is not stored in the printer queue table 1301. After recovery from the failure, the print data stored in the storage device
The data is sent to the printer engine 1304 via 1303 and output.

As described above, in the network printer system according to the present embodiment, by storing the print data in the storage device 1305, even when printing is performed again after the failure recovery work, the print data can be retransmitted. There is no need to perform this operation, and it is possible to prevent an increase in unnecessary traffic on the network.

(Eighth Embodiment) FIG. 14 shows an example of the configuration of a printer in a network printer system according to the ninth embodiment.
The printer includes a printer queue table 1401 for storing print requests, a network communication unit 1402, a controller 1403 for controlling the printer, a printer engine 1404 for printing print data, and a storage device 14 for storing received print data.
05, a panel controller 1406 for designating the number of pages of print data. A plurality of printers having such a configuration and a plurality of computers (not shown) are connected via a network. The print request received from the computer is stored in the printer queue table 1401, the print data request is sent to the computer in the order of storage, and the print data sent from the computer in response to the print data request is sent to the printer engine 1404 by the controller 1403. Printed. At this time, the print data is printed and stored in the storage device 1405 at the same time. When a failure occurs during printing, print data is stored in the storage device 1405 once. After recovery from the failure, the storage device 1405
Is sent to the printer engine 1404 via the controller 1403 and output. At this time,
The number of pages to start printing can be designated by the panel controller 1406.

As described above, in the network printer system of the present embodiment, the print data is stored in the storage device 1405, so that the print data can be re-transferred even when printing is performed again after the recovery from the failure. This eliminates the need to perform this operation, thus preventing unnecessary traffic on the network from increasing. In addition, since the output page can be specified by the panel controller 1406, print data that has already been printed is printed again. This eliminates the need for unnecessary paper consumption.

[0044]

As described above, in the network printer system according to the first aspect, the print data output device such as a computer transmits the print data of the image forming apparatus transmitted from the communication means of the image forming apparatus via the network. Since the printing status of the image forming apparatus is grasped based on the printing status signal indicating the status, it is possible to recognize the occurrence of a failure in the image forming apparatus, and to issue a printing request to another image forming apparatus when a failure occurs. Becomes possible. Therefore, in the present invention, there is no need to have information on the alternative image forming apparatus on the image forming apparatus, no need to have a transfer means to the alternative image forming apparatus, and no need to provide a special server on the network.

In the network printer system according to the second aspect, the image forming apparatus sequentially returns a response to a print request from the print data output device, so that a failure before printing can be responded to the print request and the print data request can be returned. The occurrence of a failure can be recognized by the absence, and the occurrence of a failure during printing can be recognized by not responding for a certain period of time after the transfer of the print data. Further, when a failure occurs, printing can be performed by another image forming apparatus by repeating the processing from the print request.

In the network printer system according to the third aspect, the image forming apparatus sequentially returns a response to a print request from the print data output apparatus, so that a failure before printing can be a response to the print request and the print data request can be returned. The absence of a failure allows the occurrence of a failure to be recognized, and the occurrence of a failure during printing can be recognized by the fact that no response is returned for a certain period of time after the transfer of print data and the printing status transmitted periodically. 2, it is possible to shorten the response waiting time. Therefore, even if it takes a long time from when print data is received until printing is performed, such as PostScript, the occurrence of a failure can be reliably recognized. Further, when a failure occurs, printing can be performed by another image forming apparatus by repeating the processing from the print request.

In the network printer system according to the fourth aspect, the image forming apparatus returns a response to the print request from the print data output device sequentially, so that the occurrence of a failure before printing is a response to the print request and a print data request. The absence of an error allows the occurrence of a failure to be recognized, and the occurrence of a failure during printing can be recognized by confirming the response of the printing status to the printing status confirmation request after transferring the print data. Since there is no need to wait for a fixed time in comparison, there is no need to match the waiting time between the image forming apparatus and the print data output apparatus, and the degree of freedom in mounting is increased.

In the network printer system according to the fifth aspect, in addition to the configuration and effect of the third or fourth aspect, it is possible to take various measures for recovery from failure by notifying the contents of the failure to the print data output device. It becomes possible.

In the network printer system according to the sixth aspect, in addition to the configuration and effect of the fifth aspect, since an alternative image forming apparatus can be selected, it is possible to select an image forming apparatus with more reliable printing.

In the network printer system according to the seventh aspect, in addition to the configuration and effect of the fifth aspect, it is possible to specify whether to select an alternative image forming apparatus or to re-execute on a printer in which a failure has occurred. Thus, it is possible to cope with the case where the alternative printer cannot be used.

In the network printer system according to the eighth aspect, in addition to the configuration and effect of the third or fourth aspect, the image forming apparatus further comprises a storage means for storing the print data until the end of printing, and in the event that a failure occurs. In the event of a failure, the print request is not accepted, and after the recovery from the failure, the print data that was being printed at the time of the failure is taken out of the storage means and printed. There is no need to perform this operation, and it is possible to prevent an increase in unnecessary traffic on the network.

In the network printer system according to the ninth aspect, in addition to the configuration and effect of the eighth aspect, the output page of the print data after the recovery from the failure can be designated, so that the print data already printed has been completed. Need not be printed again, and unnecessary paper consumption can be prevented.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a configuration example of a printer of a network printer system according to claims 1 and 2.

FIG. 2 is a diagram showing an example of an operation procedure of a computer and a printer when printing is performed by the network printer system according to the first and second embodiments.

FIG. 3 is a diagram showing a data format of a print request.

FIG. 4 is a diagram showing a data format of a response.

FIG. 5 is a diagram showing a configuration example of a printer of the network printer system according to the first and third aspects.

FIG. 6 is a diagram showing an example of an operation procedure of a computer and a printer when printing is performed by the network printer system according to the first and third aspects.

FIG. 7 is a diagram showing a configuration example of a printer of a network printer system according to claims 1 and 4;

FIG. 8 is a diagram showing an example of an operation procedure of a computer and a printer when printing is performed by the network printer system according to the first and fourth aspects.

FIG. 9 is a diagram showing an example of an operation procedure of a computer and a printer when printing is performed by the network printer system according to claim 5;

FIG. 10 is a diagram showing a data format when notifying a failure content.

FIG. 11 is a flowchart showing an operation example of a computer in the network printer system according to claim 6;

FIG. 12 is a flowchart showing an operation example of a computer in the network printer system according to claim 7;

FIG. 13 is a block diagram showing a configuration example of a printer of the network printer system according to claim 8;

FIG. 14 is a block diagram showing a configuration example of a printer of the network printer system according to claim 9;

[Explanation of symbols]

101, 501, 701, 1301, 1401: Printer queue tables 102, 502, 702, 1302, 1402: Network communication units (communication means) 103, 503, 703, 1303, 1403: Controllers (control means) 104, 504, 704 , 1304, 1404: Printer engine (image forming means) 1305, 1405: Storage device 1406: Panel controller

Claims (9)

[Claims] A print data output device for transmitting print data; an image forming means; a control means for controlling the image forming means; a printer queue table for storing a print request transmitted from the print data output device; A network printer system comprising: an image forming apparatus having communication means for returning a response signal to the print request from a print data output apparatus; and a network connecting the print data output apparatus and the image forming apparatus. The data output device grasps the printing status of the image forming device based on a printing status signal indicating the printing status of the image forming device transmitted from a communication unit of the image forming device via a network. Network printer system. 2. The network printer system according to claim 1, wherein said image forming apparatus returns a printable response signal in response to a printable print request from said print data output device, thereby enabling printing. Sending a print data request to the print data output device at a point in time, receiving and outputting the print data, and sending a print end to the print data output device when the printing is completed. 3. The network printer system according to claim 1, wherein said image forming apparatus returns a printable response signal in response to a printable print request from said print data output device, thereby enabling printing. A network printer system for issuing a print data request to the print data output device, receiving and outputting the print data, and periodically sending a print status signal. 4. The network printer system according to claim 1, wherein said image forming apparatus returns a printable response signal in response to a printable print request from said print data output device, and can execute printing. A network printer system sends a print data request to the print data output device at a point of time, receives and outputs print data, and sends a print status signal in response to a print status confirmation request from the print data output device. 5. The network printer system according to claim 3, wherein the image forming apparatus notifies the print data output device of the content of the failure when a failure occurs. 6. The network printer system according to claim 5, wherein when a notification of a failure content is received from the image forming apparatus, the print data output apparatus returns a response from the alternative image forming apparatus. A network printer system comprising: 7. In the network printer system according to claim 5, when the notification of the contents of the failure is received from the image forming apparatus, the print data output apparatus selects an alternative image forming apparatus or an image in which the failure has occurred. A network printer system characterized in that it is possible to specify whether to re-execute on the forming apparatus. 8. The network printer system according to claim 3, wherein the image forming apparatus includes a storage unit for storing print data, and holds the print data until the end of printing. A network printer system, wherein a print request is not accepted, print data being printed at the time of occurrence of a failure after the recovery from the failure is taken out of the storage means and printed. 9. The network printer system according to claim 8, wherein an output page of the print data after the failure recovery work can be designated.