Patent Description:
Printing devices can be utilized to form markings on a print media. As used herein, a printing device includes a hardware device that transfers a print substance on to a print media such as paper. For example, a printing device can include an inkjet printer that can deposit liquid or ink on to the print media to form a marking. As used herein, the term "print media" may include paper, photopolymers, plastics, composite, metal, wood, or the like. For example, a print media sheet may be deposited onto a finishing tray during a print job. A print media sheet may refer to a piece of print media (e.g., a sheet of paper) upon which markings may be formed to make up a physical representation of the output of a print job or a portion of an output of a print job. As used herein, the term "print job" refers to signals or states, which may be stored in a file and/or a set of files, usable to instruct a print device in forming text, images, and/or objects on print media. Among other things, the print job may include information relating to the print media. For example, a print job may include information such as an amount of print media sheets to be used in forming text, images, and/or objects on print media, a size or format (e.g., dimensions) of the printed media sheets, a paper type (e.g., paperweight, thickness, recycled content etc.), of the print media sheets, etc..

As used herein, the term "finishing tray" may refer to a component of the printing device with a surface to collect the print media sheets as a print job progresses. Printing devices according to this disclosure comprise a tray to receive print media sheets. The print media sheets may be aligned and/or arranged (e.g., registered) along an edge to form a stack on the finishing tray such that a finishing operation may be performed on a stack of print media sheets. As used herein, the term "stack" refers to a vertical pile of print media sheets. As should be apparent, a stack of print media sheets may increase in height as a print job progresses (e.g., as subsequent print media sheets are added to the stack). A post-processing action, referred to herein as "finishing," may be performed on a stack of print media sheets corresponding to a print job. For example, a finishing operation may be performed on a stack of print media sheets, including stapling, hole-punching, folding, and/or collating, etc. A finishing operation may be performed on a print job by a finisher, which may be included in a printing device, included in the finishing tray, and/or external to the printing device. As used herein, the term "finisher" refers to a mechanical and/or electrical component to perform finishing operations, in some examples, the finishing device may be a portion of the printing device, and/or the finishing tray.

Print media sheets are transferred from a print zone of a printer (e.g., a portion of a printer for applying a print substance to media, such as a printhead to apply liquid print substance to media) to the finishing tray by a media advance mechanism. As used herein, the term "a media advance mechanism" refers to an assembly of mechanical and/or electrical components to move print media with markings formed thereon to a location outside of the print zone. When the print media sheet is moved by the media advance mechanism to the finishing tray, the print media sheet may not abut the end register of the finishing tray, and this may cause the stack of print media to be misaligned for finishing operations. As used herein, the term "end register" refers to a portion of the finishing tray that may include a raised edge as to align print media sheets as they are moved to the stack of print media sheets on the finishing tray. As print media sheets are aligned against (e.g., abut) the end register, a finishing operation may be applied to the output of the print job (and produce a satisfactory result, such as opposed to an untidy stack of print media).

A paddle roller may be included in a printing device to move the print media sheets from the finishing tray to abut an end register of the finishing tray. As used herein, the term "paddle roller" refers to a device with a compiler drive element that may rotate about an axis to apply a force to a print media sheet to move the print media sheet to abut an end register of the finishing tray. For example, a paddle roller may include a plurality of paddles that may contact the print media sheets during a rotation of the paddle roller. A combination of the rotation force of the paddle roller and the friction between the paddles and the print media sheet may move the print media sheet a distance toward the end register of the finishing tray with each rotation of the paddle roller.

As a print job progresses, the stack of print media sheets may increase in height. As the stack of print media sheets increases in height, a greater amount of force on each print media sheet may be demanded to move the print media sheet to abut the end register of the finishing tray. Said differently, when the stack of print media sheets is low (e.g., during a starting portion of a print job), each rotation of the paddle roller may move the print media sheet a greater distance toward end register of the finishing tray compared to when the height of the print media sheets is high (e.g., during a final or intermediate portion of the print job). For example, when the height of the stack of print media sheets is high (e.g., during a final portion of the print job), each rotation of the paddle roller may move the print media sheet a lesser distance toward the end register of the finishing tray compared to when the height of the stack of print media sheets is low.

Some imaging devices may change a rotation per minute (RPM) (e.g., increasing and/or decreasing RPM) of the paddle roller as the stack of print media sheets increases to compensate for the demand of a greater force on each print media sheet to move toward the end register of the finishing tray as the stack increases in height. For example, the RPM increase may move a print media sheet from stack of the print media sheets to the end register of the finishing tray while a different print media sheet is exiting the print zone via the media advance mechanism. In this example, the increased RPM may cause the print media sheets to become misaligned. Misaligned print media sheets may yield unsatisfactory finishing operations by the finisher (e.g., untidy stapled stacks of print media, etc.). Thus, in some cases, the result of the finishing operation may not be satisfactory, such as because of the misaligned stack (e.g., misaligned staples, missing pages, misaligned hole punching, etc.). When the print media stack is misaligned in the finishing tray, print jobs may be repeated by a user which may waste time and resources.

Printing devices according to this disclosure comprise a paddle roller to rotate about an axis and move individual print media sheets of the print media sheets to abut an end register. The paddle roller can move print media sheets toward an end register of a finishing tray such that a print media stack is aligned such that a finishing operation may be completed. As a print job progresses, the print media sheet stack may increase in height. When the print media stack reaches a particular height, the printing device increases a quantity of rotations of the paddle roller per print media sheet and may increase the page gap between the print media sheets As used herein, the term "page gap" refers to an amount of time between a print media sheet leaving the print zone via the media advance mechanism and a new print media sheet entering the print zone. A printing device may adjust the page gap to allow enough time between print media sheets for compiling. In this way, the paddle roller may increase the quantity of rotations per print media sheet as the stack of print media sheets increases. For example, increasing the quantity of paddle roller rotations per print media sheet may move the print media sheet a sufficient distance to align it within the stack to be finished upon completion of the print job. In this way, the print media sheet may be aligned in the stack on the finishing tray before a new print media sheet exits the print zone via the media advance mechanism. Thus, the finisher may accurately complete a finishing operation on the aligned print media sheet stack (e.g., the completed print job).

<FIG> illustrates an example finishing device including a paddle roller for moving print media sheets on a finishing tray. As illustrated in <FIG>, a finishing device <NUM> may include, a media advance mechanism <NUM>, a tray <NUM>, a print media sheet <NUM>, an end register <NUM>, a paddle roller <NUM>, and a print zone <NUM>. The finishing device <NUM> may be included as a component of a printing device, or the finishing device <NUM> may be an external device separate from a printing device. Although not shown in <FIG> for clarity and so as not to obscure examples of the disclosure, the print media sheet <NUM> may include a plurality of print media sheets <NUM>. For example, the print media sheet <NUM> may be a stack including a plurality of print media sheets <NUM>. As used herein, the print media sheet <NUM> may be collectively referred to as the print media sheet <NUM> (e.g., singular), the print media sheets <NUM> (e.g., plural), and/or the stack of print media sheets <NUM>. The printing device may move an individual print media sheet <NUM> to a stack on the tray <NUM>.

The finishing device <NUM> includes a tray <NUM> that is connected to the finishing device <NUM> to receive the print media sheets <NUM>. The tray <NUM> may be formed from the finishing device <NUM> as an individual molded piece, directly connected to the finishing device <NUM> via fasteners, screws, or other means, and/or indirectly connected to the finishing device <NUM> via another component of the finishing device <NUM>. The tray <NUM> includes an end register <NUM> to compile the print media sheets <NUM> into a stack. The print media sheets <NUM> may be stacked such that the print media sheets <NUM> make contact with (e.g., abut) the end register <NUM>.

For example, the end register <NUM> may include a raised edge and the print media sheets <NUM> may abut the raised edge, thus, registering the stack of print media sheets <NUM> into an accurately aligned stack. As used herein, the term "aligned" refers to an arrangement of print media sheets <NUM> where an edge of the stack of print media sheets <NUM> are in a substantially straight line so the edges of the individual print media sheets <NUM> are aligned in a vertical stack. For example, a stack of print media sheets may be accurately aligned when no individual print media sheet <NUM> protrudes substantially outside of the stack of print media sheets <NUM>. As used herein, the term "compile" refers to creating a stack that is aligned such that the edges of the print media sheets <NUM> within the stack are evenly aligned with respect to all of the print media sheets <NUM> in the stack of print media sheets <NUM>. For example, a stack of print media sheets <NUM> may be compiled when an edge of each print media sheet <NUM> is aligned against the end register <NUM>. The stack of print media sheets <NUM> may be evenly aligned when there are no print media sheets <NUM> that are substantially misaligned (e.g., protruding/overhanging from the stack) with respect to the remaining print media sheets <NUM>.

As used herein, the term "substantially" intends that the characteristic may not be absolute but is close enough so as to achieve the purpose of the characteristic. For example, "substantially aligned" is not limited to absolute alignment and can include variations that are intended to be aligned but may not be precisely aligned. For example, "substantially aligned" print media sheet <NUM> stacks are closer to being identically uniform than not identically uniform and are stacked such that a finishing operation may be completed. Similarly, "substantially misaligned" can include orientations of the print media sheets <NUM> included in a stack in such a way as to prevent accurate finishing operations. For example, a stack of print media sheets <NUM> may be misaligned when a portion of print media sheets <NUM> are protruding from the stack. The finishing device <NUM> utilizes a paddle roller <NUM> to move the print media sheets <NUM> to form a substantially aligned stack and abut the end register <NUM> of the tray <NUM>.

The finishing device <NUM> may include a media advance mechanism <NUM> to rotate about a negative z-axis and move the print media sheets <NUM> from a print zone <NUM> in a positive x-direction to the tray <NUM>. As indicated by the coordinate plane shown in <FIG>, a positive x-direction can refer to a direction toward the right of the page, a positive z-direction can refer to a direction out of the page, and a positive y-direction can refer to a direction toward the top of the page. A negative x-direction can refer to a direction toward the left of the page, a negative z-direction can refer to a direction into the page, and a negative y-direction can refer to a direction toward the bottom of the page.

The media advance mechanism <NUM> may deposit a print media sheet <NUM> a distance <NUM> away from the end register <NUM>. When a print media sheet <NUM> is the distance <NUM> from the end register <NUM>, the print media sheet may not be compiled correctly (e.g., may be misaligned). For example, when a print media sheet <NUM> is deposited the distance <NUM> away from the end register <NUM> of the tray <NUM>, the stack of print media sheets <NUM> is unable to accurately finish the print job with the finisher of the finishing device <NUM>. The paddle roller <NUM> of the finishing device <NUM> may move the deposited print media sheet <NUM> the distance <NUM> in the negative x-direction to abut the end register <NUM>.

For example, the paddle roller <NUM> may rotate about the positive z-axis in a clockwise direction as illustrated by the arrow <NUM> to move the individual print media sheet <NUM> a distance <NUM> in the negative x-direction such that the print media sheet <NUM> may abut the end register <NUM> and may be compiled into a stack on the tray <NUM>. In this way, a finishing operation may be applied to the output of the print job (e.g., stapling) because the edge of the stack of print media sheets <NUM> will be aligned against the end register <NUM>. Although not shown in <FIG> for clarity and so as not to obscure examples of the disclosure, the print roller <NUM> may be attached to the finishing device <NUM> and/or the tray <NUM>. The paddle roller <NUM> may be formed from the finishing device <NUM> (and/or the tray <NUM>) as an individual molded piece, directly connected to the finishing device <NUM> (and/or the tray <NUM>) via fasteners, screws, or other ways, and/or indirectly connected to the finishing device <NUM> (and/or the tray <NUM>) via another component of the finishing device <NUM>.

The paddle roller <NUM> is to rotate a first quantity of rotations per print media sheet <NUM> in response to a determination that the stack of print media sheets corresponds to a first height. For example, the paddle roller <NUM> may rotate about the positive z-axis and move individual print media sheets <NUM> of the print media sheets <NUM> to abut an end register106 of the tray <NUM> and form a stack of print media sheets <NUM>, wherein the paddle roller is to rotate a first quantity of rotations per print media sheet <NUM> in response to a determination that the stack of print media sheets corresponds to a first height. As the finishing device <NUM> processes a print job comprising a print media sheets <NUM>, the stack of print media sheets <NUM> will increase in height as the print job progresses. As the height if the print media sheets <NUM> increases, the distance that an individual print media sheet <NUM> moves in the negative x-direction per paddle roller <NUM> rotation may decrease. Thus, the finishing device <NUM> may increase a quantity of paddle roller <NUM> rotations per print individual print media sheet <NUM> such that each print media sheet <NUM> may be substantially aligned against the end register <NUM> of the tray <NUM>.

The paddle roller <NUM> rotates a second quantity of rotations per print media sheet <NUM> in response to a determination that the stack of print media sheets <NUM> corresponds to a second height greater than the first height, the second quantity of rotations being larger than the first quantity of rotations. Further, the finishing device <NUM> may increase a quantity of paddle roller <NUM> rotations per print individual print media sheet <NUM> such that each print media sheet <NUM> may be substantially aligned against the end register <NUM> of the tray <NUM>.

For example, the paddle roller <NUM> is to rotate a third quantity of rotations per the individual print media sheet <NUM> in response to a determination that the stack of print media sheets corresponds to a third height greater than the second height, the third quantity of rotations. In some examples, the finishing device <NUM> may increase the page gap to correspond to the registration time per print media sheet <NUM> when the stack of print media sheets <NUM> increases in height to compensate for the increased quantity of paddle roller <NUM> rotations per print media sheet <NUM>.

As used herein, the term "registration time" refers to the amount of time to compile a print media sheet <NUM> to abut the end register <NUM>. For example, the finishing device <NUM> may adjust an amount of time between a first print media sheet <NUM> leaving the print zone <NUM> via the media advance mechanism <NUM> and a second print media sheet <NUM> entering the print zone (e.g., a page gap). For example, increasing the page gap increases the registration time and allows time for the particular quantity of rotations of the paddle roller <NUM> per print media sheet <NUM> to be completed before another print media sheet <NUM> interacts with the paddle roller <NUM>. In this way, the printing device may avoid misalignment of print media stacks <NUM>.

In other examples, the finishing device <NUM> may alter the first quantity of rotations per individual print media sheet <NUM> to move a print media sheet to abut the end register <NUM> of the tray <NUM> based on a size of an individual print media sheet. In some examples, a print job may include a predetermined amount of print media sheets <NUM>, wherein the predetermined amount of print media sheets <NUM> is of a predetermined length and a predetermined thickness. For example, a print media sheet <NUM> having a length of <NUM> inches (<NUM>) may move a distance <NUM> in the negative x-direction to abut the end register <NUM> after <NUM> rotations of the paddle roller <NUM> at the starting portion of a print job. In contrast, a print media sheet <NUM> having a length of <NUM> (<NUM>) inches may move the deposited print media sheet <NUM> a distance <NUM> in the negative x-direction to abut the end register <NUM> after <NUM> rotations of the paddle roller <NUM> during the starting portion of the print job. While specific example dimensions of print media sheets <NUM> are discussed herein, it should be understood that the dimensions may vary, and the examples should not be interpreted in a limiting sense.

In other examples, the finishing device <NUM> may alter the first quantity of rotations per print media sheet <NUM> based on a paper type (e.g., a thickness) of the individual print media sheet <NUM>. For example, a print media sheet <NUM> having a thickness of <NUM> may move a distance <NUM> in the negative x-direction to abut the end register <NUM> after <NUM> rotations of the paddle roller <NUM> at the starting portion of a print job. However, the finishing device <NUM> may determine that the thickness of the print media sheets <NUM> may increase the stack height at a different rate and may alter the quantity of rotations of the paddle roller <NUM> per print media sheet <NUM> to move the deposited print media sheet <NUM> the distance <NUM> in the negative x-direction to abut the end register <NUM>. For example, a print media sheet <NUM> having a thickness of <NUM> may increase the print media stack <NUM> height at a different rate than a print media sheet <NUM> having a thickness of <NUM>. Based on the determined thickness of the print media sheet <NUM>, the finishing device <NUM> may alter the quantity of paddle roller <NUM> rotations per print media sheet <NUM> from <NUM> to <NUM> to move the deposited print media sheet <NUM> a distance <NUM> in the negative x-direction to abut the end register <NUM> as the print job progresses. Said differently, the finishing device <NUM> may determine that a print media sheet <NUM> having a thickness of <NUM> may have a higher print media sheet <NUM> stack at the starting portion of a print job compared to a print media sheet <NUM> having a thickness of <NUM>. Thus, to compensate, the finishing device <NUM> may alter a quantity of rotations of the paddle roller <NUM> per print media sheet <NUM>. While specific example thickness of print media sheets <NUM> are discussed herein, it should be understood that the thickness may vary, and the examples should not be interpreted in a limiting sense.

<FIG> describes examples of a finishing device <NUM> compiling print media sheets <NUM> from a print job into a substantially aligned stack against the end register <NUM> such that a finishing operation (e.g., stapling) may be accurately performed on the print media sheets <NUM> of the print job. The quantity of rotations of the paddle roller <NUM> are increased to compensate for the height of the print media sheets <NUM>, and a page gap is increased to allow for the registration time per print media sheet <NUM> to allow the paddle roller <NUM> sufficient time to move the deposited print media sheet <NUM> a distance <NUM> in the negative x-direction to abut the end register <NUM> to the tray <NUM>.

In some examples, when physical representations of a print job are formed on print media, the result may include a number of print media sheets <NUM> (e.g., <NUM>, <NUM>, <NUM>, <NUM>, etc. individual print media sheets). <FIG> illustrate an example output of a printing device in tray <NUM> at different discrete times in the output process. For example, <FIG> illustrates a first time (e.g., t<NUM>), referred to as a starting portion of the print job, <FIG> illustrates a second time (e.g., t<NUM>), referred to as an intermediate portion of the print job, and <FIG> illustrates a third time (e.g., t<NUM>), referred to as a final portion of the print job. It is noted that while only three discrete portions of the print job are illustrated, a print job may include more or less than three discrete portions.

<FIG> illustrates an example paddle roller at a starting portion of a print job. <FIG> illustrates a paddle roller <NUM>-<NUM> rotating in a counterclockwise direction as indicated by arrow <NUM> to move print media sheets <NUM> into a stack at a first height <NUM>-<NUM> on a tray <NUM> to abut an end register <NUM> during a starting portion of a print job. Paddle roller <NUM>-<NUM> rotates a first quantity of rotations per print media sheet for the stack corresponding to the first height <NUM>-<NUM>. Although not shown in <FIG> for clarity and so as not to obscure examples of the disclosure, the paddle roller <NUM>-<NUM> is included as a component of a finishing device (e.g., the finishing device <NUM> of <FIG>).

For example, a printing device may determine that the output of a print job includes <NUM> individual print media sheets <NUM>, the stack of print media sheets <NUM> may be at a first height <NUM>-<NUM> at the starting portion of the print job. In this example, the first height <NUM>-<NUM> may be print media sheets <NUM> numbered <NUM>-<NUM>, and because first height <NUM>-<NUM> is at a starting portion of the print job, the height of the stack of print media sheets <NUM> may be lower in comparison to the final height of the stack of the print media sheets for the print job (e.g., <NUM> individual print media sheets <NUM>).

During the starting portion of the print job, the paddle roller <NUM>-<NUM> may rotate a first quantity of rotations of <NUM> times per print media sheet <NUM> to move the deposited print media sheet <NUM> a distance <NUM> in the positive x-direction to abut the end register <NUM> of the tray <NUM>. For example, the printing device may set a quantity of rotations of the paddle roller <NUM>-<NUM> per print media sheet <NUM> for a starting portion of the print job (e.g., print media sheets <NUM> numbered <NUM>-<NUM>), wherein the quantity of rotations moves the deposited print media sheet <NUM> a distance <NUM> in the positive x-direction to abut the end register <NUM> to the tray <NUM>. In some examples, the first quantity of rotations and the first height <NUM>-<NUM> of the stack of print media sheets <NUM> correspond to a first registration time, and the second quantity of rotations and the second height <NUM>-<NUM> of the stack of print media sheets <NUM> correspond to a second registration time. As the print job progresses, the printing device may increase the quantity of rotations of the paddle roller <NUM>-<NUM> as the height of the stack of print media sheets <NUM>-<NUM> increases to a second height <NUM>-<NUM>.

<FIG> illustrates an example paddle roller at an intermediate portion of a print job. <FIG> illustrates a paddle roller <NUM>-<NUM> rotating in a counterclockwise direction as indicated by arrow <NUM> to move print media sheets <NUM> a distance <NUM> into a stack at a second height <NUM>-<NUM> on a tray <NUM> to abut an end register <NUM> during an intermediate portion of a print job. Although not shown in <FIG> for clarity and so as not to obscure examples of the disclosure, the paddle roller <NUM>-<NUM> may be included as a component of a printing device (e.g., the printing device of <FIG>).

For example, during an intermediate portion of the print job (e.g., print media sheets <NUM> numbered <NUM>-<NUM>), the paddle roller <NUM>-<NUM> may have difficulty moving the deposited print media sheet <NUM> the distance <NUM> in the positive x-direction to abut the end register <NUM> of the tray <NUM>. Said differently, the paddle roller <NUM>-<NUM> may not move the print media sheet <NUM> the distance <NUM> for accurate finishing utilizing <NUM> rotations of the paddle roller <NUM>-<NUM> per print media sheet <NUM>. To compensate for the second height <NUM>-<NUM>, the printing device alters the quantity of rotations of the paddle roller <NUM>-<NUM> per print media sheet <NUM> for an intermediate portion of the print job (e.g., print media sheets numbered <NUM>-<NUM>). For example, the printing device may increase the quantity of paddle roller <NUM>-<NUM> rotations from <NUM> to <NUM> rotations per print media sheet <NUM>. To compensate for the increased amount of time <NUM> rotations per print media sheet <NUM> takes in comparison to <NUM> rotations per print media sheet <NUM>, the printing device may increase the page gap to correspond to a registration time to avoid misalignment of the print media stack at a second height <NUM>-<NUM>. For example, the printing device may direct a page gap to increase based on the determination that the stack of print media sheets corresponds to the second height of the stack. As the print job progresses, the printing device may increase the quantity of rotations of the paddle roller <NUM>-<NUM> as the height of the stack of print media sheets <NUM>-<NUM> increases to a third height <NUM>-<NUM>.

<FIG> illustrates an example paddle roller at a final portion of a print job. <FIG> illustrates a paddle roller <NUM>-<NUM> rotating in a counterclockwise direction as indicated by arrow <NUM> to move print media sheets <NUM> a distance <NUM> into a stack at a third height <NUM>-<NUM> on a tray <NUM> to abut an end register <NUM> during a final portion of a print job. Although not shown in <FIG> for clarity and so as not to obscure examples of the disclosure, the paddle roller <NUM>-<NUM> may be included as a component of a printing device (e.g., the printing device of <FIG>).

For example, during a final portion of the print job (e.g., <NUM>-<NUM> individual print media sheets <NUM>) the paddle roller <NUM>-<NUM> may have difficulty moving a print media sheet <NUM> a distance <NUM> in the positive x-direction to abut the end register <NUM> of the tray <NUM>. Said differently, the paddle roller <NUM>-<NUM> may not move the print media sheet <NUM> the distance <NUM> for accurate finishing utilizing <NUM> rotations of the paddle roller <NUM>-<NUM> per print media sheet <NUM>. To compensate for the third height <NUM>-<NUM>, the printing device may alter the quantity of rotations of the paddle roller <NUM>-<NUM> per print media sheet <NUM> for a final portion of the print job (e.g., <NUM>-<NUM> individual print media sheets <NUM>). For example, the printing device may increase the quantity of paddle roller <NUM>-<NUM> rotations from <NUM> to <NUM> rotations per print media sheet <NUM>. To compensate for the increased amount of time <NUM> rotations per print media sheet <NUM> takes in comparison to <NUM> rotations per print media sheet <NUM>, the printing device may increase the page gap to correspond to a registration time to avoid misalignment of the print media <NUM> stack at the third height <NUM>-<NUM>.

While the print job described in conjunction with <FIG> are described as including <NUM> individual print media sheets <NUM>, it should be understood that a print job may have more or less than <NUM> individual print media sheets <NUM>. Similarly, a printing device may alter the paddle roller <NUM> rotations more or less than described in the examples used in conjunction with <FIG>.

<FIG> illustrate the progression of a print job where a quantity of rotations of the paddle roller <NUM> per print media sheet <NUM> increases as the stack height <NUM> increases. Accordingly, the page gap may be increased to correspond to the registration time increasing as the quantity of rotations of the paddle roller <NUM> per print media sheet <NUM> increases to maintain stack alignment such that a finishing operation may be applied to the output of the print job.

<FIG> illustrates an example of a printing device including a controller for moving print media sheets on a finishing tray. As illustrated in <FIG>, a printing device <NUM> may include a controller <NUM>, a media advance mechanism301, a finishing tray <NUM>, a print media sheet <NUM>, an end register <NUM>, a paddle roller <NUM>, a print zone <NUM>, and a finishing zone <NUM>. The printing device may move the print media sheets <NUM> to a stack on the finishing tray <NUM>. Although not shown in <FIG> for clarity and so as not to obscure examples of the disclosure, the printing device <NUM> may include a print mechanism within the print zone <NUM> to transfer a print substance to print media sheets <NUM>.

The printing device <NUM> may include the media advance mechanism <NUM> to move the print media sheets from the print zone <NUM> in a positive x-direction to a finishing zone <NUM>, and the plurality of print media sheets <NUM> may form a stack of print media sheets <NUM>. As used herein, the term "finishing zone" refers to an area on the finishing tray <NUM> where the media advance mechanism301 may move the print media sheets <NUM> after existing the print zone <NUM>. The finishing zone <NUM> may include the finisher to perform finishing operations on the print media sheets <NUM> when they have been substantially aligned to abut the end register <NUM> on the finishing tray <NUM> for accurate finishing (e.g., stapling). The media advance mechanism301 may move the individual print media sheet <NUM> a distance <NUM> from the end register <NUM>. To avoid misalignment and inaccurate finishing operations, the printing device <NUM> my utilize the paddle roller <NUM> to rotate about a negative z-axis in a clockwise direction as illustrated by the arrow <NUM> to move individual print media sheets <NUM> the distance <NUM> in the negative-x direction to abut the end register <NUM>. The printing device may include a controller <NUM> to make determinations regarding the printing device <NUM> and/or the print job.

As used herein, the term "controller" refers to a computing device that may contain a processing resource and a memory resource to execute instructions. The controller <NUM> may be included in the printing device <NUM>, a standalone device, or in a separate device that may be located external to the printing device <NUM>. The controller <NUM> may determine information relating to the print job and execute instructions based on that information. For example, the information relating to the print job may refer to a number of individual print media sheets <NUM> (e.g., the output) of a print job, a size of print media sheet <NUM> (e.g., dimensions), a thickness of the print media sheet <NUM>, and other information related to paper type (e.g., density), etc. For example, the controller <NUM> causes the paddle roller <NUM> to rotate a first quantity of rotations per the individual print media sheets <NUM> in response to a determination that a stack of print media sheets <NUM> corresponds to a first height. In this example, the first height may be such that the paddle roller <NUM> may be able to move a print media sheet the distance <NUM> to abut the end register <NUM> of the finishing tray <NUM> with <NUM> rotations of the paddle roller <NUM> per print media sheet <NUM>. As the print job progresses, the stack of print media sheets <NUM> may increase in height.

The controller <NUM> causes the paddle roller <NUM> to rotate a second quantity of rotations per the individual print media sheets <NUM> in response to a determination that the stack of print media sheets <NUM> corresponds to a second height of the stack. For example, the second height of the stack may be such that the paddle roller <NUM> may be able to move the print media sheets <NUM> to form a substantially aligned stack and abut the end register <NUM> of the finishing tray <NUM> with <NUM> rotations. Accordingly, the controller <NUM> may compensate for the increased amount of time <NUM> rotations per individual print media sheet <NUM> takes in comparison to <NUM> rotations per individual print media sheet <NUM>. For example, the controller <NUM> may increase the page gap to correspond to the registration time to avoiding misalignment of the print media stack <NUM>. In other examples, as the print job progresses, the print media sheet <NUM> stack may increase a second time.

The controller <NUM> may cause the paddle roller <NUM> to rotate a third quantity of rotations per the individual print media sheet <NUM> in response to a determination that the stack of print media sheets <NUM> corresponds to a third height of the stack. For example, the third height of the stack may be such that the paddle roller <NUM> may be able to move the print media sheets <NUM> the distance <NUM> to form a substantially aligned stack and abut the end register <NUM> of the finishing tray <NUM> with <NUM> rotations. Accordingly, the controller <NUM> may compensate for the increased amount of time <NUM> rotations per individual print media sheet <NUM> takes in comparison to <NUM> rotations per individual print media sheet <NUM>, and the controller <NUM> may increase the page gap to correspond to the registration time to avoid misalignment of the print media stack <NUM>.

<FIG> describes examples of a quantity of paddle roller <NUM> rotations per individual print media sheet <NUM> increasing such that a stack of print media sheets <NUM> may be accurately aligned. The page gap is increased accordingly to compensate for the increased registration time of the quantity of rotations of the paddle roller <NUM>. The aligned stack is received on the finishing tray <NUM> including an end register <NUM> to compile the stack of print media sheets <NUM> from the paddle roller <NUM> and align the stack of print media sheets <NUM> against the end register <NUM>.

<FIG> illustrates an example processing resource and an example memory resource of an example printing device. <FIG> illustrates an example controller <NUM>, including a processing resource <NUM> and a memory resource <NUM>. For example, the controller <NUM> may include a processing resource <NUM> which may be a central processing unit (CPU), a semiconductor-based microprocessor, and/or other hardware devices suitable for retrieval and execution of instructions stored in a memory resource (e.g., in a non-transitory computer readable medium) <NUM>. The example processing resource <NUM> may fetch, decode, and execute instructions. As an alternative, or in addition to, retrieving and executing instructions, the example processor may include an electronic circuit that may include electronic components for performing the functionality of executed instructions.

In some examples, the processing resource <NUM> may be a plurality of hardware processing units that may cause machine-readable instructions to be executed. The processing resource <NUM> may include central processing units (CPUs) among other types of processing units. The memory resource <NUM> may be any type of volatile or non-volatile memory or storage, such as random-access memory (RAM), flash memory, storage volumes, a hard disk, or a combination thereof.

The memory resource <NUM> may store instructions thereon, such as instructions <NUM>, <NUM>, <NUM>, and <NUM>. When executed by the processing resource <NUM>, the instructions may cause the controller <NUM> to perform specific tasks and/or functions. For example, the memory resource <NUM> may store instructions <NUM> which may be executed by the processing resource <NUM> to cause the controller <NUM> to receive signals indicative of a print job. In some examples, when a signal indicative of a print job is sent to a printing device (e.g., the printing device <NUM> of <FIG>), the controller <NUM> may determine the amount of individual print media sheets (e.g., print job output) that may be utilized to complete the print job. Further, responsive to reception of signals indicative of the print job, the paddle roller is to cause formation of a stack of print media sheets, and further wherein the stack of print media sheets is to be stapled. For example, the controller <NUM> may utilize the information about the print job to determine a height of the print media sheet stack (e.g., the print media sheets <NUM> of <FIG>).

The memory resource <NUM> may store instructions <NUM> which may be executed by the processing resource <NUM> to cause the controller <NUM> to set an initial quantity of rotations of a paddle roller per print media sheet for a starting portion of the print job, wherein rotation of the paddle roller is to cause the print media sheet to move to abut an end register of a finishing tray. For example, the controller <NUM> may cause the paddle roller to rotate a first quantity of rotations per the individual print media sheets in response to a determination that a stack of print media sheets corresponds to a first height at an initial a first time (e.g., t<NUM> described in conjunction with <FIG>) of the print job.

The memory resource <NUM> may store instructions <NUM> which may be executed by the processing resource <NUM> to cause the controller <NUM> to set an intermediate quantity of rotations of the paddle roller per print media sheet for an intermediate portion of the print job. For example, the controller <NUM> may cause the paddle roller to rotate a second quantity of rotations per the individual print media sheets in response to a determination that the stack of print media sheets corresponds to a second height of the stack at a second time (e.g., t<NUM> described in conjunction with <FIG>) of the print job.

The memory resource <NUM> may store instructions <NUM> which may be executed by the processing resource <NUM> to cause the controller <NUM> to set a final quantity of rotations of the paddle roller per print media sheet for a final portion of the print job. For example, the controller <NUM> may cause the paddle roller to rotate a third quantity of rotations per the individual print media sheet in response to a determination that the stack of print media sheets corresponds to a third height of the stack at a third time (e.g., t<NUM> described in conjunction with <FIG>) of the print job.

The controller <NUM> may increase a page gap to correspond to a registration time for the increased amount of time the quantity or rotations per print media sheet takes during the intermediate and final portions of the print job. For example, the rotations per individual print media sheet may take longer during the final portion of the print job (e.g., <NUM> rotations) in comparison to the intermediate portion (e.g., <NUM> rotations) per print individual media sheet. The printing device may increase the page gap to correspond to a registration time to avoid misalignment of the print media stack. A finishing operation may be applied to the print job (and produce a satisfactory result, such as opposed to an untidy stack of print media.

<FIG> illustrates an example processing resource and an example memory resource of an example printing device. <FIG> illustrates, an example controller <NUM>, including a processing resource <NUM> and a memory resource <NUM>. The memory resource <NUM> may store instructions thereon, such as instructions <NUM>, <NUM>, and <NUM>. When executed by the processing resource <NUM>, the instructions may cause the controller <NUM> to perform specific tasks and/or functions. For example, the memory resource <NUM> may store instructions <NUM> which may be executed by the processing resource <NUM> to cause the controller <NUM> to determine a size (e.g., dimensions) of the print media sheets. For example, the controller <NUM> may determine that a print job includes print media sheets of a length of <NUM> inches (<NUM>). In this example, the controller <NUM> may alter a quantity of rotations of a paddle roller to move an individual print media sheet a distance (e.g., the distance <NUM> of <FIG>) to form a substantially aligned stack and abut the end register (e.g., the end register <NUM> of <FIG>) of the finishing tray (e.g., the finishing tray <NUM> of <FIG>).

The memory resource <NUM> may store instructions <NUM> which may be executed by the processing resource <NUM> to cause the controller <NUM> to set the initial quantity of rotations of the paddle roller per print media sheet, the intermediate quantity of rotations of the paddle roller per print media sheet, the final quantity of rotations of the paddle roller per print media sheet, or a combination thereof, based on a determined size of the print media sheet. For example, the controller <NUM> may determine that the paddle roller may use a quantity of rotations of <NUM> per print media sheet based on the determined size. The controller <NUM> may further increase a page gap to correspond to a registration time based on the progress of the print job.

The memory resource <NUM> may store instructions <NUM> which may be executed by the processing resource <NUM> to cause the controller <NUM> to set a page gap based on the initial quantity of rotations of the paddle roller per print media sheet, the intermediate quantity of rotations of the paddle roller per print media sheet, the final quantity of rotations of the paddle roller per print media sheet, or a combination thereof. In this way the controller <NUM> may avoid misalignment of the stack of print media sheets and a finishing operation may be applied to the print job and produce a satisfactory result, such as opposed to an untidy stack of print media.

In the foregoing detailed description of the disclosure, reference is made to the accompanying drawings that form a part hereof, and in which is shown by way of illustration how examples of the disclosure may be practiced. These examples are described in sufficient detail to enable those of ordinary skill in the art to practice the examples of this disclosure, and it is to be understood that other examples may be utilized and that process, electrical, and/or structural changes may be made without departing from the scope of the disclosure.

The figures herein follow a numbering convention in which the first digit corresponds to the drawing figure number and the remaining digits identify an element or component in the drawing.

The proportion and the relative scale of the elements provided in the figures are intended to illustrate the examples of the disclosure and should not be taken in a limiting sense. Further, as used herein, "a plurality of" an element and/or feature refers to more than one of such elements and/or features.

Claim 1:
A finishing device (<NUM>), comprising:
a tray (<NUM>, <NUM>, <NUM>) to receive print media sheets (<NUM>, <NUM>, <NUM>); and
a paddle roller (<NUM>, <NUM>, <NUM>) to rotate about an axis and move individual print media sheets of the print media sheets to abut an end register (<NUM>, <NUM>, <NUM>) of the tray and form a stack of print media sheets, wherein the paddle roller is to rotate a first quantity of rotations per print media sheet in response to a determination that the stack of print media sheets corresponds to a first height (<NUM>-<NUM>),
characterized in that the paddle roller is to rotate a second quantity of rotations per print media sheet in response to a determination that the stack of print media sheets corresponds to a second height (<NUM>-<NUM>) greater than the first height, the second quantity of rotations being larger than the first quantity of rotations.