BACKGROUND OF THE INVENTION

Field of the Invention

The present invention relates to execution control of a print job in an image forming apparatus.

Description of the Related Art

Recent image forming apparatuses include a variety of sheet feed units, such as a plurality of cassettes and a manual feed tray, and it is possible to perform printing by selecting a sheet to use from a plurality of kinds of sheets without the need to exchange sheets each time. However, even though the above-described plurality of sheet feed units is provided, it is difficult to satisfy each of a variety of needs of a user. Because of this, in many cases, the sheet feed unit is used in accordance with uses or purposes in such a manner that the sheet feed cassette is used for the sheet whose frequency of use is high and the sheet a large number of which is used at a time, and the manual feed tray is used for the sheet whose frequency of use is low and the preprint sheet dedicated to specific printed matter. Further, in the case where it is made possible to create printed matter using a plurality of sheets different in sheet size and sheet type while using a plurality of sheet feed units as described above, the time and effort to grasp which sheet is set in which sheet feed unit are required and it becomes necessary to perform complicated sheet setting at the time of generating a print job. Consequently, there are also many image forming apparatuses having a function to automatically select an optimum sheet feed unit based on information on sheet setting included in a print job. Due to this, by a user specifying in advance the size and type of a sheet that the user uses in a print job, an optimum sheet feed unit is selected by the image forming apparatus and printing is performed without the need for the user to take into consideration the setting on the sheet feed unit side.

In an environment in which the image forming apparatus such as described above is shared and used by a plurality of users (for example, in an office and the like), there is a case where the sheet prepared and set by a user is used by another user. As the cause of this, in addition to misunderstanding and erroneous operation, for example, there may be a case where a plurality of print jobs is queued and the rest of the sheet used in the preceding print job is also used in the subsequent print job by the automatic selection processing of the sheet feed unit described previously. In such a situation, there may occur a case where the sheet is already used and it is no longer possible to perform printing even though a user who has set the sheet inputs a print job. Regarding this point, for example, Japanese Patent Laid-Open No. 2005-104614 has proposed a technique to temporarily suspend printing immediately before sheet feed at the time of a sheet being fed from a specific sheet feed unit specified by a user and to cause a user to confirm whether to continue printing processing (hereinafter, called “confirmation printing function”). According to the technique of Japanese Patent Laid-Open No. 2005-104614, a confirmation operation is performed without exception before a sheet is fed, and therefore, it is possible to avoid the occurrence of such a problem that it is not possible to perform printing because there is no sheet. Further, Japanese Patent Laid-Open No. 2005-104614 has also proposed to display an arbitrary message at the time of causing a user to confirm whether to continue printing processing. Due to this, it is made possible for a user to determine whether or not the suspended print job is the print job of the user.

Further, there is a case where execution of a print job is suspended by regarding the state as a so-called out-of-sheet (no sheet) state because all the sheets are used on the way during printing processing or the necessary sheet is not set originally in the sheet feed unit. In such a case, usually, by a user who has input the print job noticing that there is no sheet and replenishing the necessary sheet, the printing processing is resumed. However, in the case where a user who has input the suspended print job does not notice that there is no sheet or the state is such that it is not possible to immediately perform replenishment, the suspended state of printing processing is left as it is. In this case, it is not possible to perform printing processing of another queued print job (subsequent print job), which can be printed with the sheet currently set in the image forming apparatus and the printing processing stagnates. Then, in an environment in which a plurality of users shares and uses the image forming apparatus, it is not possible to simply cancel the suspended print job of another user, and therefore, this leads to stagnation of business.

Consequently, there exists an image forming apparatus having a function to perform control so as to perform a subsequent print job first (overtaking printing) with an elapse of a predetermined time as a trigger in the case where execution of a print job is suspended for some reason and the situation is brought about in which execution of subsequent print jobs is impeded. Such a function is called a timeout function. By this timeout function, the print job put into the suspended state is cancelled or put into the held state so that it is possible to resume the printing processing later. By doing so, even in the case where some print job is left in the suspended state, it is possible to avoid the occurrence of such a situation in which it is not at all possible to use the image forming apparatus and business stagnates.

Here, also in the state where printing processing is temporarily suspended by the confirmation printing function described previously, execution of a subsequent print job is postponed. Consequently, in the case where a user leaves a job of confirmation printing as it is without performing any action, such as giving instructions to continue printing, it is not at all possible to perform printing processing using the image forming apparatus. However, in a situation in which printing processing is suspended temporarily by the confirmation printing function, in the case where overtaking of a subsequent print job is performed, or the suspended print job is cancelled by the timeout function described previously, such a new problem as follows may arise. Specifically, in the case where a comparatively short time is set as the timeout time, there is a case where printing processing of a subsequent print job is started before a user confirms the sheet and gives instructions to continue printing, or the suspended print job is cancelled. In particular, in the case where the timeout function is made ineffective (or the timeout time is set to 0 sec), a timeout occurs immediately after the job of confirmation printing suspends temporarily to confirm whether or not to continue printing, and therefore, the confirmation printing function itself is no longer effective.

Consequently, an object of the present invention is to make an attempt to cause the timeout function and the confirmation printing function to coexist.

SUMMARY OF THE INVENTION

The image forming apparatus according to the present invention is an image forming apparatus configured to execute print jobs in order of input, the image forming apparatus including: control unit configured to, in a case where a target print job does not satisfy a condition necessary for execution and the target print job is not a print job which has been specified as requiring user confirmation for execution to start, suspend execution of the target print job and a subsequent print job that follows the target print job, and start execution of the subsequent print job in accordance with an elapse of a first time period set in advance in a state where the condition is not satisfied, wherein the control unit, in a case where the target print job is a print job which has been specified as requiring user confirmation for execution to start and the condition necessary for execution of the target print job is not satisfied, is configured to suspend execution of the target print job and the subsequent print job and not to start execution of the subsequent print job in accordance with an elapse of the first time period in a state where the condition is not satisfied.

Further features of the present invention will become apparent from the following description of exemplary embodiments with reference to the attached drawings.

