Patent Description:
Card production systems include processing devices that process card substrates (hereinafter "cards") to form the final card product. Such processes may include a printing process, a laminating or transfer process, a data reading process, a data writing process, and/or other process used to form the desired credential. An ink jet card printer is a form of card production system that utilizes an ink jet print head to print images to cards. <CIT> describes an inkjet printing device comprising a fast scan module. <CIT> describes a digital printer comprising at least two printheads that are operative to mark simultaneously on one or more media. <CIT> describes a digital printing press with automated media transport.

Embodiments of the present disclosure are directed an ink jet card printer having a card sensor and methods of operating the ink jet card printer. The ink jet card printer includes a transport belt, a print unit including an ink jet print head, the sensor and a gantry that supports the ink jet print head and the sensor for movement relative to the transfer belt. In one exemplary method, a card is loaded onto the transport belt by driving the card along a processing axis using an exposed surface of the transport belt. The sensor and the ink jet print head are moved relative to the card using the gantry. A current position of the card relative to the processing axis is detected using the sensor. An image is printed to the card using the ink jet print head when the detected current position of the card indicates that the card is supported on the transport belt in a print position. Printing an image to the card using the ink jet print head is interrupted when the detected current position of the card indicates that the card is not in the print position.

Another exemplary method is directed to the operation of an ink jet card printer having a card transport including first and second belts, and a print unit including an ink jet print head, a sensor and a gantry. In the method, a first card is loaded onto the first belt by driving the first card along a processing axis using an exposed surface of the first belt. A second card is loaded onto the second belt by driving the second card along a processing axis using an exposed surface of the second belt. The sensor and the ink jet print head are moved relative to the first and second cards using the gantry. Current positions of the first and second cards relative to the processing axis are detected using the sensor. A first image is printed to the first card and a second image is printed to the second card using the ink jet print head when the detected current positions of the first and second cards indicate that the first card is supported on the first belt in a first print position, and the second card is supported on the second belt in a second print position. Printing images to the first and second cards is interrupted when the detected current position of the first card indicates that the first card is not in the first print position, or when the detected current position of the second card indicates that the second card is not in the second print position.

One exemplary embodiment of the ink jet card printer includes a card transport, a print unit, and a controller. The card transport includes a transport belt having an exposed surface configured engage and feed a card along a processing axis. The print unit includes an ink jet print head, a sensor and a gantry. The gantry is configured to move the ink jet print head and the sensor along a fast scan axis that is parallel to the processing axis and a slow scan axis that is perpendicular to the processing axis. The controller is configured to load a card onto the transport belt, detect a current position of the card relative to the processing axis using the sensor, print an image to the card using the ink jet print head when the detected current position of the card indicates that the card is supported on the transport belt in a print position, and interrupt printing an image to the card using the ink jet print head when the detected current position of the card indicates that the card is not in the print position.

This Summary is not intended to identify key features or essential features of the claimed subject matter, nor is it intended to be used as an aid in determining the scope of the invention which is defined by the appended claims.

Embodiments of the present disclosure are generally directed to a card feeder of an ink jet card printer that is configured to facilitate the feeding individual cards to a print position for printing by an ink jet print head that is moved through a print zone using a gantry during printing operations. The card feeder has a raised position, in which at least a portion of the card feeder extends into the print zone. As a result, the card feeder would obstruct printing operations if left in the raised position. This issue is avoided by moving the card feeder to a lowered position during printing operations, in which the card feeder is displaced from the print zone, using a lift mechanism.

These and other embodiments of the present disclosure are described more fully hereinafter with reference to the accompanying drawings. Elements that are identified using the same or similar reference characters refer to the same or similar elements. The various embodiments of the present disclosure may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the present disclosure to those skilled in the art.

<FIG> and <FIG> are simplified side and top views of an ink jet card printer <NUM> in accordance with embodiments of the present disclosure. In some embodiments, the printer <NUM> includes a print unit <NUM>, and a card transport <NUM>. The card transport <NUM> is configured to feed individual cards <NUM> along a processing axis <NUM>. The print unit <NUM> includes an ink jet print head <NUM> and a gantry <NUM>. The print head <NUM> is configured to perform a printing operation on individual cards <NUM> supported by the card transport <NUM> in a print position <NUM> along the processing axis <NUM>. The gantry <NUM> is configured to move the print head <NUM> through a print zone <NUM> during printing operations.

In some embodiments, the printer <NUM> includes a controller <NUM>, which represents one or more distinct controllers of the printer <NUM>, each of which includes at least one processor that is configured to execute program instructions stored in a computer-readable media or memory of the printer <NUM>, which may also be represented by the controller <NUM>, or another location. Any suitable patent subject matter eligible computer readable media or memory may be utilized including, for example, hard disks, CD-ROMS, optical storage devices, flash memory, magnetic storage devices, or other suitable computer readable media or memory that do not include transitory waves or signals. The execution of the instructions by the controller <NUM> controls components of the printer <NUM> to perform functions and method steps described herein.

As discussed in greater detail below, the card printer <NUM> may include one or more card feeders <NUM>, such as card feeders 120A and 120B, that are each configured to deliver cards <NUM> to, and receive cards <NUM> from, the card transport <NUM>. The printer <NUM> may also include one or more conventional card flippers <NUM>, such as flippers 122A and 122B, that are configured to invert the cards <NUM>. A conventional card supply <NUM>, such as a card cartridge containing a stack of cards, may be provided to supply cards <NUM> for processing by the printer <NUM>, and processed cards may be discharged and collected by a suitable card collector (e.g., a hopper) <NUM>.

The ink jet print head <NUM> may be any suitable conventional ink jet print head that is configured to perform a direct printing operation to individual cards <NUM> supported in the print positions <NUM> along the processing axis <NUM>. The gantry <NUM> includes a conventional gantry for moving the print head <NUM> along a fast scan axis <NUM> that is substantially parallel to the processing axis <NUM>, and a slow scan axis <NUM> that is substantially perpendicular to the processing axis <NUM>, as shown in <FIG>, during printing operations. As used herein, the term "fast scan axis" refers to the axis along which the print head <NUM> is moved by the gantry <NUM> during an active printing phase of the operation, during which ink is discharged from the print head <NUM> to form the image on the card <NUM>. The term "slow scan axis" refers to the axis along which the print head <NUM> is moved by the gantry <NUM> during an inactive printing phase (ink is not discharged from the print head) to position the print head <NUM> for the next active printing phase.

In some embodiments, the gantry <NUM> and the print head <NUM> may occupy the print zone <NUM> during printing operations, which is indicated by dashed boxes in <FIG> and <FIG>. The print zone <NUM> generally extends from the processing axis <NUM>, or immediately above the processing axis <NUM>, into the space above the card transport <NUM> and the card feeders <NUM>. The print zone <NUM> may also surround the card transport <NUM> and the card feeders <NUM>, as shown in <FIG>.

In some embodiments, the card feeders <NUM> each include a lift mechanism <NUM> to move the card feeders <NUM> to a lowered position <NUM>, in which the card feeders <NUM> are displaced from the print zone <NUM>, such as below the print zone <NUM>, as indicated by card feeder 120A in <FIG>, and the card feeders 120A and 120B in <FIG>. <FIG> is an isometric view of exemplary card transport <NUM> and card feeders <NUM> in their lowered positions <NUM>, <FIG> is a side view of an exemplary printer <NUM> with the card feeders <NUM> in their lowered positions <NUM>, and <FIG> is a side view of the printer <NUM> of <FIG> with frame side walls removed, in accordance with embodiments of the present disclosure.

The lift mechanisms <NUM> may also move the card feeders <NUM> to a raised position <NUM>, in which at least a portion of the card feeders <NUM> extend into the print zone <NUM>, and the card feeders <NUM> are positioned to feed cards <NUM> to, or receive cards <NUM> from, the card transport <NUM>, as indicated by the card feeder 120B in <FIG> and the card feeders 120A and 120B in <FIG> and <FIG>. <FIG> is a side view of the exemplary printer <NUM> of <FIG> with the card feeders <NUM> in their raised positions, and <FIG> is a side view of the printer <NUM> of <FIG> with frame side walls removed, in accordance with embodiments of the present disclosure. Thus, the card feeders <NUM> may be moved to their raised positions <NUM> by the lift mechanisms <NUM> to facilitate feeding cards <NUM> to, or receiving cards <NUM> from the card transport <NUM>.

Thus, the lift mechanisms <NUM> may be used to move the card feeders <NUM> from their raised positions <NUM>, in which at least a portion of the card feeders <NUM> would obstruct a printing operation, to their lowered positions <NUM>, in which the card feeders <NUM> do not obstruct the print zone <NUM>, to enable the print head <NUM> to be moved through the print zone <NUM> by the gantry <NUM> and perform a printing operation.

In some embodiments, the card transport <NUM> includes belts <NUM>, such as first and second belts 140A and 140B (i.e., belt feeders or conveyors), that are each supported by rollers <NUM> for movement along a belt path. In one example, the first and second belts 140A and 140B are each supported by four rollers <NUM>, which are supported by a belt frame <NUM>, such as side walls 146A and 146B of the belt frame <NUM> (<FIG>). The belts <NUM> include exposed portions <NUM> (i.e., top surfaces) adjacent the processing axis <NUM>. The exposed portion <NUM> of each of the belts <NUM> contacts the cards <NUM> and is used to feed the cards <NUM> along the processing axis <NUM>. Additionally, the cards <NUM> are supported on the exposed portions <NUM> in the print positions <NUM>.

Motors 154A and 154B are respectively configured to independently drive the first and second belts 140A and 140B along their belt paths. Thus, the exposed portion <NUM> of the first belt 140A may independently feed a card <NUM> along the processing axis <NUM> in a direction toward the second belt 140B or in a direction toward the card feeder 120A using the motor 154A, and the exposed portion <NUM> of the second belt 140B may independently feed a card <NUM> along the processing axis <NUM> in the direction toward the first belt 140A, or in the direction toward the card feeder 120B using the motor 154B.

The belts <NUM> of the card transport <NUM> may take on any suitable form. In some embodiments, the belts <NUM> are conventional vacuum belts that are coupled to a vacuum source <NUM> (i.e., a source of negative pressure), such as a regenerative vacuum blower. The vacuum source <NUM> may be shared by the belts <NUM>, as shown in <FIG>, or separate vacuum sources 158A and 158B may respectively be used by the belts 140A and 140B, as shown in <FIG>. Chambers <NUM> couple the negative pressure generated by the vacuum source <NUM> to the exposed portions <NUM> of the belts <NUM>. The negative pressure is communicated to a top side of the exposed portions <NUM> through apertures <NUM> in the belts, which are shown in <FIG> and <FIG>, and is used to secure cards <NUM> to the exposed portions <NUM> during card feeding and printing operations. Thus, when a card <NUM> engages the top surface of the exposed portion <NUM> of one of the belts <NUM>, the negative pressure generated by the vacuum source <NUM> or sources 158A and 158B adheres the card <NUM> to the belt <NUM>. When the belts <NUM> are driven by the corresponding motor <NUM>, the adhered card <NUM> is driven along the processing axis <NUM>.

During a printing operation, with the card feeders <NUM> in their lowered positions <NUM>, each of the belts <NUM> may feed a card <NUM> along the processing axis <NUM> to the corresponding print position <NUM>, in which the exposed top surfaces <NUM> of the cards <NUM> are at the border of the print zone <NUM>, as shown in <FIG>, <FIG>, <FIG> and <FIG>. The print head <NUM> may perform a print operation on the top surfaces <NUM> of the cards <NUM> supported in the print positions <NUM>. Thus, the print head <NUM> may print an image to the exposed surface <NUM> of the card <NUM> supported in the print position <NUM> on the belt 140A, print an image to the surface <NUM> of the card <NUM> supported in the print position <NUM> on the belt 140B, and/or simultaneously print images to the surfaces <NUM> of both cards <NUM> supported in the print positions <NUM> on the belts 140A and 140B during a single printing operation.

For example, referring to <FIG>, with the card feeders <NUM> in their lowered positions <NUM>, and the cards <NUM> held in the print positions <NUM> against the exposed portions <NUM> of the belts 140A and 140B due to the negative pressure generated by the vacuum source <NUM> or sources 158A and 158B (<FIG>, <FIG>, <FIG> and <FIG>), the gantry <NUM> may move the print head <NUM> along the fast scan axis <NUM> (processing axis <NUM>) over the cards <NUM>, while the print head <NUM> prints image lines to the surfaces <NUM>, as indicted by arrow <NUM>. After the print head <NUM> is moved past the end of the card <NUM> adjacent the card feeder 120B, the gantry <NUM> shifts the print head <NUM> along the slow scan axis <NUM>, as indicated by arrow <NUM>. The gantry <NUM> then moves the print head <NUM> back along the fast scan axis <NUM> (arrow <NUM>), during which the print head <NUM> prints image lines to the surfaces <NUM> of the cards <NUM>. The gantry <NUM> again shifts the position of the print head <NUM> along the slow scan axis <NUM> (arrow <NUM>), and the print head <NUM> prints image lines as the gantry <NUM> moves the print head <NUM> along the fast scan axis <NUM> (arrow <NUM>). These steps of printing image lines while moving the print head <NUM> along the fast scan axis <NUM> and shifting the position of the print head <NUM> along the slow scan axis <NUM>, are repeated until the images have been printed to the surfaces <NUM> of the cards <NUM>. Accordingly, a single print operation may simultaneously print images to two cards <NUM> supported on the belts <NUM>.

To print a full edge-to-edge image on a card <NUM>, the print head <NUM> may be configured to print an image that is slightly larger than the surface <NUM> of the card <NUM>. As a result, some ink will overspray the edges of the card <NUM>.

In some embodiments, the exposed surface <NUM> of each belt <NUM> has a smaller surface area than the card <NUM>. That is, the width and length of the exposed belt surfaces <NUM> are selected such that they are less than the corresponding width and length of the cards <NUM>, as generally shown in <FIG> with the cards <NUM> shown in phantom lines. Thus, when a card <NUM> is in the print position <NUM>, the entirety of the exposed belt surface <NUM> is covered by the card <NUM>, and a perimeter portion <NUM> of the card <NUM> extends beyond the edges of the exposed belt surface <NUM>. This allows the print head <NUM> to print images that extend to the edges of the surfaces <NUM> of cards <NUM> while protecting the exposed belt surface <NUM> from ink contamination.

In some embodiments, the printer <NUM> includes an ink overspray collector <NUM> that surrounds a perimeter of the exposed belt surface <NUM> and extends beyond the edges of the cards <NUM> when in their print positions <NUM>, as shown in <FIG>. Thus, the collector <NUM> is positioned to receive ink that is sprayed over the lengthwise and widthwise edges of the cards <NUM> during a printing operation. In some embodiments, the ink overspray collector <NUM> is a disposable component that may be periodically removed and replaced by an operator of the printer <NUM>. The collector <NUM> may be formed of plastic, paper, cardboard, or another suitable material. In some embodiments, the collector <NUM> is a single piece of material having an opening 184A for the exposed belt surface <NUM> of the belt 140A, and an opening 184B for the exposed belt surface <NUM> of the belt 140B.

As mentioned above, the card feeders <NUM> are each configured to deliver cards <NUM> to, and receive cards <NUM> from the card transport <NUM> when in their raised positions <NUM> (<FIG> and <FIG>). The card feeders <NUM> may also receive cards <NUM> for processing from the card supply <NUM>, such as using card feeder 120A, and discharge processed cards <NUM> to the collector <NUM>, such as using the card feeder 120B, as indicated in <FIG>.

In some embodiments, the card feeders <NUM> each include at least one pinch roller pair <NUM>, such as pinch roller pairs 190A and 190B, as shown in <FIG>, <FIG> and <FIG>. In some embodiments, at least a portion of one or both of the pinch roller pairs <NUM> extends into the print zone <NUM> when the card feeder <NUM> is in the raised position <NUM>, as shown in <FIG>. The pinch roller pairs 190A and 190B are respectively positioned adjacent ports <NUM> and <NUM> of the card feeder <NUM>, with the port <NUM> being positioned adjacent an input/output end <NUM> of the corresponding belt <NUM>, as shown in <FIG>. Each pinch roller pair <NUM> may include an idler roller <NUM> and a motorized feed roller <NUM> (<FIG> and <FIG>) that are supported by a card feeder frame <NUM>, such as between side walls 201A and 201B of the frame <NUM>, as shown in <FIG>. While the idler roller <NUM> is illustrated as being the top roller in the provided examples, it is understood that the positions of the rollers <NUM> and <NUM> may be reversed. A cover <NUM> may be positioned between the pinch roller pairs 190A and 190B to cover a portion of the path through which cards <NUM> are fed through the card feeder <NUM>, as shown in <FIG>.

The card feeders 120A and 120B respectively include motors 204A and 204B (<FIG>) for driving the motorized rollers <NUM> to feed a card <NUM> supported between one or both of the pinch roller pairs 190A and 190B along a card feed axis <NUM>. The separate motors <NUM> of the feeders <NUM> allow the controller <NUM> to independently control the card feeders <NUM>. As a result, the card feeder 120A may be used to deliver a card <NUM> to the belt 140A while the card feeder 120B delivers a card <NUM> to the collector <NUM>, for example.

The card feed axis <NUM> of each feeder <NUM> is substantially parallel to a vertical plane extending through the processing axis <NUM>. Thus, as shown in the top view of <FIG>, the card feed axes <NUM> of the feeders <NUM> are oriented substantially parallel (e.g., ±<NUM> degrees) to the processing axis <NUM> within a horizontal plane.

In some embodiments, the lift mechanisms <NUM> pivot the frame <NUM> of the card feeders <NUM> about a pivot axis <NUM> (<FIG>) during movement of the card feeders <NUM> between their raised and lowered positions <NUM> and <NUM>. As a result, the orientation of the card feed axis <NUM> relative to the processing axis <NUM> in a vertical plane changes with movement of the card feeders <NUM> between their raised and lowered positions <NUM> and <NUM>. When the card feeder <NUM> is in its lowered position <NUM>, the card feed axis <NUM> is at an oblique angle (e.g., <NUM>-<NUM> degrees) to the processing axis <NUM> in the vertical plane, as shown in <FIG>. When the card feeder <NUM> is in its raised position, the card feed axis <NUM> is substantially parallel to the processing axis <NUM> in the vertical plane, as shown in <FIG>, allowing the card feeder <NUM> to deliver a card <NUM> to the adjacent belt <NUM>, or receive a card <NUM> from the adjacent belt <NUM> using one or more of the pinch roller pairs <NUM>.

In some embodiments, the pivot axis <NUM> is defined by a pivotable connection <NUM> between the card feeder frame <NUM> and the belt frame <NUM>, as indicated in <FIG>. In one embodiment, the pivotable connection or hinge <NUM> is formed between the side walls 201A and 201B of the card feeder frame <NUM> and the corresponding side walls 146A and 146B of the belt frame <NUM>.

In one exemplary embodiment, each lift mechanism <NUM> includes a cam <NUM>, a cam follower <NUM> and a motor <NUM>, as shown in <FIG> and <FIG>. The separate motors <NUM> allow the controller <NUM> to independently control each lift mechanism <NUM>. In one example, each cam <NUM> is supported by the belt frame <NUM> for rotation about an axis <NUM> (<FIG>), and each cam follower <NUM> is supported by the card feeder frame <NUM> and pivots with the card feeder frame <NUM> about the pivot axis <NUM>. Alternatively, the positions of the cam <NUM> and the cam follower <NUM> may be reversed where the cam <NUM> is supported by the belt frame <NUM> and the cam follower <NUM> is supported by the card feeder frame <NUM>. In some embodiments, the cam follower <NUM> is biased to engage the cam <NUM> using a suitable biasing mechanism, such as a spring.

During an exemplary lift operation, in which the card feeder <NUM> is moved from the lowered position <NUM> (<FIG>) to the raised position <NUM> (<FIG>), the controller <NUM> activates the motor <NUM> of the lift mechanism <NUM> to drive rotation of the cam <NUM> about the axis <NUM> in the direction indicated by arrow <NUM> in <FIG>. As the cam <NUM> rotates, it slides and presses against a cam surface <NUM> (<FIG>) of the cam follower <NUM>. This drives the card feeder frame <NUM> to pivot about the pivot axis <NUM> until the card feeder <NUM> reaches the raised position <NUM> shown in <FIG>. The operation is reversed to move the card feeder <NUM> back to its lowered position <NUM>. That is, the controller activates the motor <NUM> of the lift mechanism <NUM> to drive rotation of the cam <NUM> about the axis <NUM> in the direction opposite arrow <NUM> (<FIG>). During this rotation of the cam <NUM>, the cam surface <NUM> of the cam follower <NUM> slides along the cam <NUM> and the card feeder frame <NUM> pivots about the pivot axis <NUM> until the card feeder <NUM> reaches the lowered position <NUM> shown in <FIG>.

Alternative lift mechanisms <NUM> may also be employed. For example, different lift mechanisms may be used to pivot the card feeders <NUM> between their raised and lowered positions <NUM> and <NUM>, such as a screw drive, or another suitable lift mechanism. Additionally, the lift mechanisms <NUM> may be configured to move the card feeders <NUM> linearly between the raised and lowered positions <NUM> and <NUM>.

In some embodiments, a lateral stabilizer <NUM> is used in connection with each of the card feeders <NUM> to ensure substantial coaxial alignment in the horizontal plane between the card feed axis <NUM> and the processing axis <NUM> of the adjacent belt <NUM>, as shown in <FIG>, when the card feeders <NUM> are in their raised positions <NUM>. One example of a suitable lateral stabilizer <NUM> is shown in <FIG>, which are front and top isometric views of a portion of the printer <NUM> at the interface between the card feeder 120A and the belt 140A with the ink collector <NUM> removed. In some embodiments, the lateral stabilizer <NUM> is positioned between the pinch roller pair 190A at the port <NUM> and the input/output end <NUM> of the adjacent belt 140A, as shown in <FIG>.

In one embodiment, the lateral stabilizer <NUM> includes a first stabilizing member <NUM> connected to the card feeder frame <NUM>, and a second stabilizing member <NUM> connected to the belt frame <NUM>. Thus, the first stabilizing member <NUM> moves with movement of the card feeder frame <NUM> about the pivot axis <NUM> relative to the second stabilizing member <NUM>. The first stabilizing member <NUM> engages with the second stabilizing member <NUM> in a cooperating manner when the card feeder <NUM> is moved from the lowered position <NUM> to the raised position <NUM> to provide the desired lateral alignment of the card feed axis <NUM> and the processing axis <NUM>. In some embodiments, the first and second stabilizing members <NUM> and <NUM> are displaced from each other when the card feeder <NUM> is in the lowered position <NUM>.

In one exemplary embodiment, the first stabilizing member <NUM> is in the form of a rib member and the second stabilizing member is in the form of a groove <NUM>, as shown in <FIG>. Alternatively, the positions of the rib member and groove may be reversed. The groove <NUM> may be formed in a bar <NUM> extending between the side walls 146A and 146B of the belt frame <NUM>. As the card feeder <NUM> is moved from the lowered position <NUM> to the raised position <NUM>, the rib member <NUM> is received within the groove <NUM>, as shown in <FIG>, to align the card feed axis <NUM> with the processing axis <NUM> and maintain the alignment during card feeding operations between the card feeder 120A and the belt 140A.

Ideally, each card feeder <NUM> supports a received card <NUM> such that a central axis of the card <NUM> is aligned with the card feed axis <NUM>. This ensures that the card <NUM> is fed to the adjacent belt <NUM> in alignment with the processing axis <NUM>, which allows for accurate positioning of the card <NUM> in the print position <NUM> on the belt <NUM> and accurate printing of an image to the card surface <NUM>.

In some embodiments, each card feeder <NUM> includes a card alignment mechanism <NUM>, an example of which is illustrated in the top view of a portion of the printer <NUM> provided in <FIG> with the cover <NUM> removed. The card alignment mechanism <NUM> is configured to prevent misalignment between a card <NUM> supported by the one or more pinch roller pairs <NUM> of the card feeder <NUM> and the card feed axis <NUM>. One embodiment of the card alignment mechanism <NUM> includes a reference wall <NUM>, a pusher wall <NUM> and a biasing mechanism <NUM>. The reference wall <NUM> is aligned parallel to the card feed axis <NUM> and has a fixed position relative to the card feeder frame <NUM>. The pusher wall <NUM> is moveable relative to the card feeder frame <NUM> and the reference wall <NUM>. The biasing mechanism <NUM> is configured to bias the pusher wall <NUM> toward the reference wall <NUM>. Embodiments of the biasing mechanism <NUM> include a spring or another conventional biasing mechanism.

As a card <NUM> is received by the card feeder <NUM> with the central axis of the card <NUM> being offset from the card feed axis <NUM> or non-parallel to the card feed axis <NUM>, the pusher wall <NUM> pushes the card <NUM> toward the reference wall <NUM> due to the bias produced by the biasing mechanism <NUM>. This causes an edge of the card <NUM> to engage the reference wall <NUM>. As the card <NUM> continues to be fed into the card feeder <NUM> by the pinch roller pairs <NUM>, the edge of the card <NUM> engaging the reference wall <NUM> aligns with the reference wall <NUM> and aligns the central axis of the card <NUM> with the card feed axis <NUM>.

The printer <NUM> may include one or more sensors <NUM> to facilitate various card feeding operations, such as receiving a card <NUM> in the card feeders <NUM> and positioning a card <NUM> in the print position <NUM> on the belts <NUM>. In one embodiment, the printer <NUM> includes a card sensor <NUM> for detecting the presence or absence of a card at each side of the card transport <NUM>, as indicated in <FIG>. In some embodiments, the card sensors <NUM> are positioned between the pinch roller pair 190A and the adjacent belt <NUM>. In some embodiments, the card sensors <NUM> are supported by the card feeder frame <NUM>, as shown in <FIG> and <FIG>. The card sensors may take on any suitable form, such as an optical card sensor having an emitter <NUM> and a receiver <NUM>, as shown in <FIG>.

During reception of a card <NUM> by a card feeder <NUM> in its lowered position <NUM>, the sensor <NUM> may be used to detect the leading edge of the card <NUM> being fed toward the card transport belt <NUM>, which may indicate that the card <NUM> is fully received in the card feeder <NUM>. The card feeder <NUM> may then be moved from the lowered position <NUM> to the raised position <NUM>. After the card feeder <NUM> is moved to the raised position <NUM>, the corresponding card sensor <NUM> may be used to detect the trailing edge of the card <NUM> as the card is fed to the adjacent belt <NUM>. The controller <NUM> may use this detection of the trailing edge of the card <NUM> to control the belt <NUM> to position the card <NUM> in the desired print position <NUM>.

The card sensors <NUM> may also be used by the controller <NUM> to control the reception of cards <NUM> fed from the belts <NUM> by the card feeders <NUM>. For example, as a card <NUM> is fed from the belt <NUM> toward the card feeder <NUM>, the card sensor <NUM> may detect the leading edge of the card <NUM>. This detection may be used by the controller <NUM> to control the pinch roller pairs <NUM> to receive the card <NUM> in the card feeder <NUM>. The card <NUM> may then be fed into the card feeder <NUM> using the pinch roller pairs <NUM> until the sensor <NUM> detects the trailing edge of the card <NUM> indicating that the card <NUM> has been fully received within the card feeder <NUM> and that the card feeder <NUM> is ready to be moved to its lowered position <NUM>.

As mentioned above, the printer may optionally include one or more card flippers <NUM> that may be used to invert cards <NUM> to facilitate printing operations on both sides of the cards <NUM>. Each card flipper <NUM> may be configured to receive a card <NUM> from the adjacent card feeder <NUM>, the card supply (flipper 122A) or the card collector (flipper 122B), rotate the card <NUM> about a flipping axis <NUM> to invert the card <NUM>, and pass the inverted card <NUM> back to the adjacent card feeder <NUM>, which can deliver the inverted card <NUM> to the card transport <NUM> and the print unit <NUM> for a printing operation. The card flippers <NUM> may each be conventional card flippers. One suitable card flipper <NUM> which may be used by the printer is described in <CIT>, which issued to HID Global Corporation.

In some embodiments, each flipper <NUM> includes a pinch roller pair <NUM> that is configured to hold the card <NUM> during rotation about the flipping axis <NUM>. One or more motors <NUM> (<FIG> and <FIG>) are used to drive rotation of a gear <NUM>, that supports the pinch roller pair <NUM> and a card <NUM> supported by the pinch roller pair, about the flipping axis <NUM>. In some embodiments, the card feed axis <NUM> of each flipper <NUM> is configured to rotate into alignment with the card feed axis <NUM> of the adjacent card feeder <NUM> when it is in the lowered position <NUM>. The motor <NUM> may also drive the pinch roller pair <NUM> to feed a card <NUM> supported by the pinch roller pair <NUM> to the pinch roller pair 190B at the port <NUM> of the adjacent card feeder <NUM>, such as shown in <FIG>. The adjacent card feeder <NUM> may then move to the raised position <NUM> and feed the card <NUM> to the adjacent belt <NUM>, as shown in <FIG>.

Some embodiments of the present disclosure are directed to methods of printing an image to one or more cards <NUM> using the ink jet card printer <NUM>. In one embodiment of the method, a card <NUM>, which may have been received from the supply <NUM> and fed to the card feeder 120A by the card flipper 122A, is supported by the pinch roller pairs <NUM> of the card feeder 120A while in its lowered position <NUM>, as shown in <FIG>. The card feeder 120A is moved to its raised position <NUM> using the corresponding lift mechanism <NUM>, and the card <NUM> is discharged from the card feeder 120A to the belt 140A using the pinch roller pair 190A. The card feeder 120A is then moved to the lowered position <NUM> (<FIG> and <FIG>) and out of the print zone <NUM> using the lift mechanism <NUM>, and the card <NUM> is fed along the processing axis <NUM> by the belt 140A to the print position <NUM> (<FIG>). An image is then printed to the surface <NUM> of the card <NUM> using the print head <NUM>, which involves moving the print head <NUM> with the gantry <NUM> through the print zone <NUM>, as indicated in <FIG> and <FIG>.

Some embodiments of the method involve performing a print operation using the ink jet card printer <NUM> to print images on two cards <NUM> simultaneously. One example of such a method will be described with reference to <FIG>, which are simplified top views of the card transport <NUM> and the card feeders 120A and 120B during various stages of the method. Initially, a pair of cards <NUM> may be fed from the supply <NUM> to the card transport <NUM> with the card feeders <NUM> in their lowered positions <NUM>. This may involve feeding a first card <NUM> from the supply <NUM> through the card flipper <NUM> to the card feeder 120A, as shown in <FIG> and <FIG>. The card feeder 120A may then be moved to its raised position <NUM> using the lift mechanism <NUM>, and the first card 106A is fed to the belt 140A by the pinch roller pair 190A, as shown in <FIG>. The card feeder 120A may then return to its lowered position <NUM>, and a second card <NUM> may be fed from the supply <NUM> through the flipper 122A to the card feeder 120A in the same manner as the first card. During the feeding of the second card 106A to the card feeder 120A, the first card 106A may be fed by the belt 140A to the belt 140B, during which the card 106A is simultaneously supported by both belts 140A and 140B, as shown in <FIG>. The card 106A may then be moved by the belt 140B to the print position <NUM>, as shown in <FIG>. The second card 106B is fed to the belt 140A using the pinch roller pair 190A of the card feeder 120A, as indicated in <FIG>, and the second card 106B is moved along the processing axis <NUM> by the belt 140A to its print position <NUM>, as shown in <FIG>. The card feeder 120A is then moved to its lowered position <NUM>.

With the cards 106A and 106B supported in their print positions <NUM> on the belts 140B and 140A, and the card feeders 120A and 120B in their lowered positions <NUM> (<FIG>), a printing operation is simultaneously performed on the first and second cards 106A and 106B using the print unit <NUM>, as discussed above with reference to <FIG>. This printing operation involves moving the ink jet print head <NUM> in the fast scan direction <NUM> across the cards <NUM> and moving the ink jet print head <NUM> in a slow scan axis <NUM> that is perpendicular to the fast scan axis <NUM> through the print zone <NUM> using the gantry <NUM>. The cards <NUM> are imaged by the ink jet print head (i.e., active printing phase) while the print head <NUM> is moved in the fast scan direction <NUM> by the gantry <NUM>.

After the images have been printed to the cards 106A and 106B, the card feeders 120A and 120B are returned to their raised positions <NUM> by the lift mechanisms <NUM>, and the cards 106A and 106B are delivered to the adjacent card feeders 120A and 120B using the belts 140A and 140B, as indicated in <FIG>. After receiving the cards 106A and 106B, the card feeders 120A and 120B are moved to their lowered positions <NUM> by the lift mechanisms <NUM>, and the cards 106A and 106B are fed to the corresponding flippers 122A and 122B, such as generally shown in <FIG>. The flippers 122A and 122B invert the cards 106A and 106B and feed the inverted cards back to the card feeders 120A and 120B, which are then returned to their raised positions <NUM>. The cards 106A and 106B are then fed back to the adjacent belts 140A and 140B by the card feeders 120A and 120B, as indicated in <FIG>. The belts 140A and 140B then move the cards 106B and 106A to the print positions <NUM> (<FIG>) and the card feeders 120A and 120B are again moved to their lowered positions <NUM>. The print head <NUM> then prints images to the non-imaged surfaces <NUM> of the cards 106A and 106B as discussed above with reference to <FIG>.

With images printed to both sides of the cards 106A and 106B, the cards may be discharged to the collector <NUM> using the card feeder 120B. The card feeder 120B is first moved to the raised position <NUM>, and the belt 140B feeds the card 106A to the card feeder 120B. The card feeder 120B is then moved to its lowered position <NUM>, and the card 106A is fed to the collector <NUM> through the flipper 122B (<FIG>). The card 106B is fed from the belt 140A to the belt 140B and the card feeder 120B is returned to the raised position <NUM>. The card feeder 120B then receives the card 106B from the belt 140B, and is moved to its lowered position <NUM> by the corresponding lift mechanism <NUM>. The card 106B can then be discharged from the card feeder 120B to the collector <NUM> through the flipper 122B.

Some embodiments of the present disclosure operate to ensure that at least one card <NUM> is properly registered with a print position <NUM> and an active print zone of the belt 140A or 140B prior to commencing a print operation. In some embodiments, when a card <NUM> is in the print position <NUM> for a given belt <NUM>, the card <NUM> is in position to receive an image printed using the ink jet print head <NUM>. Additionally, in some embodiments, when a card <NUM> is in the print position <NUM> for a given belt <NUM>, the card <NUM> entirely covers the exposed surface <NUM> of the belt that engages the card <NUM> to prevent ink contamination of the belt <NUM> during a printing operation on the card <NUM>. Embodiments of the present disclosure operate to ensure that the cards <NUM> are in the proper print positions <NUM> (<FIG>) before printing images to the cards <NUM> with the print head <NUM>.

The print positions <NUM> for the cards <NUM> on the belts <NUM> generally correspond to active print zones of the ink jet print head <NUM>, in which the print head <NUM> is configured to print images during a print operation. Thus, the gantry <NUM> will move the print head <NUM> along the fast and slow scan axes <NUM> and <NUM>, as discussed above with reference to <FIG>, and the print head <NUM> will discharge ink to the corresponding active print zone to form an image on a card <NUM> that is positioned within the active print zone. Since ink is not discharged by the print head <NUM> outside the active print zone during a print operation, edge-to-edge printing of an image to the surface <NUM> of a card <NUM> requires the entire surface <NUM> to be positioned within the active print zone. Embodiments of the present disclosure operate to ensure that cards <NUM> are positioned within an active print zone before performing a print operation. Additionally, embodiments of the present disclosure operate to compensate or correct for misregistration of the cards <NUM> with the active print zones to enable a printing operation to be performed.

<FIG> is a simplified top plan view of the card transport <NUM> and illustrates a card 106A that is in proper registration with the print position <NUM> of the belt 140A and the corresponding active print zone 300A. As a result, the print head <NUM> should accurately print an image to the surface <NUM> of the card 106A during a print operation without contaminating the belt 140A with ink.

<FIG> also illustrates a card 106B that is misregistered with the print position <NUM> of the belt 140B and the active print zone 300B. If a print operation were to be performed on the misregistered card 106B, the portion <NUM> of the card 106B extending outside the active print zone 300B would not receive the printed image. As a result, if a printing operation were to be performed, the image printed to the card 106B would not extend over the entire surface <NUM> (edge-to-edge image). Additionally, since the exposed surface <NUM> of the belt 140B is not entirely covered by the card 106B, the uncovered portion of the surface <NUM> will receive a portion of the printed image, thus contaminating the belt 140B with ink.

In some embodiments, the printer <NUM> includes a sensor <NUM> (<FIG> and <FIG>) that may be used by the controller <NUM> to determine whether cards <NUM> are properly positioned in their print positions <NUM> and within the active print zones <NUM> on the belts 140A or 140B prior to performing a print operation on the cards <NUM> using the print head <NUM>. In some embodiments, the sensor <NUM> is supported by the gantry <NUM> for movement with the print head <NUM> along the fast axis <NUM> and the slow axis <NUM>. The sensor <NUM> may be attached to a carriage <NUM> (<FIG>) that supports the print head <NUM> for movement by the gantry <NUM>.

A suitable coordinate system is used to establish a location of the sensor <NUM> relative to features of the card transport <NUM>, such as the belts <NUM>, for example. In one example, the coordinate system may include one axis that is aligned with the processing axis <NUM> and the fast scan axis <NUM>, and a second axis that is aligned with the slow scan axis <NUM>. Locations of the print positions <NUM>, the active print zones, the belts <NUM>, the processing axis <NUM>, and other features of the printer <NUM> may be stored in memory of the controller <NUM>. Thus, the controller <NUM> can establish a location of the sensor <NUM> and a location of features detected beneath the sensor <NUM>, such as cards <NUM> and card edges, relative to the print positions <NUM>, the active print zones <NUM>, and other the features of the printer <NUM>.

The sensor <NUM> may take on any suitable form. In one embodiment, the sensor <NUM> includes a reflective sensor having an emitter <NUM> and a receiver <NUM>, as illustrated in <FIG>. The emitter <NUM> is configured to emit electromagnetic radiation <NUM> toward the processing axis <NUM>, and the receiver <NUM> is configured to detect a reflection of the emitted electromagnetic radiation <NUM>, as indicated by arrow <NUM>'. The intensity of the reflected electromagnetic radiation <NUM>' and changes in the intensity of the reflected electromagnetic radiation <NUM>' can be used to detect the presence or absence of a card <NUM> beneath the sensor <NUM>, as well as features of the cards <NUM>, such as edges of the cards <NUM>, for example. Other suitable types of sensors may also be used for the sensor <NUM>, such as an optical sensor, a capacitance sensor, a camera, or other suitable type of sensor.

<FIG> is a flowchart illustrating a method of operating the ink jet card printer <NUM> to ensure that each card <NUM> that is supported on the belt 140A or 140B is properly registered in the corresponding print position <NUM> before a print operation is performed, in accordance with embodiments of the present disclosure. At <NUM> of the method, a card <NUM> is loaded onto the card transport belt <NUM> in accordance with one or more embodiments described above. For example, a card 106A or 106B may be loaded onto a corresponding card transport belt 140A or 140B by driving the cards 106A or 106B along the processing axis <NUM> using the belts 140A or 140B, as discussed above and illustrated in <FIG>. At <NUM>, the sensor <NUM> is moved along with the inkjet print head <NUM> relative to the card <NUM> using the gantry <NUM>. Note that the ink jet print head <NUM> and the gantry <NUM> are not shown in <FIG> in order to simplify the drawing. At <NUM>, a current position of the card <NUM> relative to the processing axis <NUM> is detected using the sensor <NUM>.

In some embodiments of step <NUM>, the sensor <NUM> is initially moved to a position relative to the belt 140A or 140B where the detection of the presence of a card <NUM> by the sensor <NUM> indicates that the card <NUM> is properly registered with the print position <NUM>. For example, the sensor <NUM> may be moved in step <NUM> to a location <NUM> along the processing axis <NUM> that is within the active print zone 300A to detect the presence of the card 106A, as shown in <FIG>, which would indicate that the card 106A is in the print position <NUM>. Here, a presumption is made that if the card <NUM> is present, then it is likely in the print position <NUM>. While this embodiment may not be used to detect a precise location of a card <NUM> along the processing axis <NUM>, the fast axis <NUM> or the slow axis <NUM>, and specifically determine that the card <NUM> is correctly registered with the corresponding active print zone 300A, it may be used to detect various errors, such as a malfunction of the vacuum source <NUM> (<FIG>) and/or a serious misfeed of the card <NUM>, for example.

Step <NUM> may also involve moving the sensor <NUM> along a path that extends through the print positions <NUM> and the active print zones <NUM> to detect the current position of the card <NUM> in step <NUM> through the detection of a position of one or more edges of the card <NUM>. For example, the sensor <NUM> may be moved along the processing axis <NUM> and the fast scan axis <NUM> and along the path indicated by arrow <NUM>, to positions <NUM> and <NUM> to detect leading edges <NUM> of the cards 106A and 106B, and/or to positions <NUM> and <NUM> to detect trailing edges <NUM> of the cards 106A and 106B, as indicated in <FIG>. Based on the detected position of the leading edge <NUM> and/or the trailing edge <NUM>, the current positions of the cards 106A and 106B along the processing axis <NUM> can be determined by the controller <NUM> in step <NUM>.

Additionally, the position of a card <NUM> relative to the processing axis <NUM> and along the slow scan axis <NUM> relative to the processing axis <NUM> or a corresponding belt <NUM> may be determined in a similar manner by moving the sensor <NUM> along the slow scan axis <NUM> and through the print position <NUM> and active print zone <NUM> of the corresponding belt <NUM> and detecting the position of the side edges <NUM> and/or <NUM> of the card <NUM>, which are generally perpendicular to the edges <NUM> and <NUM>. For example, as indicated in <FIG>, a location of the side edge <NUM> of the card 106A may be detected by moving the sensor <NUM> in step <NUM> along a path indicated by arrow <NUM> that extends along the slow scan axis <NUM> and through a position <NUM>, and the side edge <NUM> of the card 106B may be detected by moving the sensor <NUM> in step <NUM> along the path indicated by arrow <NUM> that extends along the slow scan axis <NUM> and through a position <NUM>. Similarly, the position of the side edge <NUM> of the card 106A may be detected in step <NUM> by moving the sensor <NUM> along the path <NUM> and through a position <NUM>, and the position of the side edge <NUM> of the card 106B may be detected in step <NUM> by moving the sensor <NUM> along the path <NUM> and through a position <NUM>, as indicated in <FIG>.

As a result, the current positions of the cards 106A and 106B detected using the sensor <NUM> in step <NUM> may include, for example, a position of the cards 106A and 106B along the processing axis <NUM> based on a detection of the leading edges <NUM> or the trailing edges <NUM>, and/or a position of the cards 106A and 106B along the slow scan axis <NUM> relative to the processing axis <NUM> based on a detection of the side edges <NUM> or <NUM> of the cards 106A and 106B.

At <NUM> of the method, an image is printed to the card <NUM> using the inkjet print head <NUM> when the detected current position of the card <NUM> indicates that the card <NUM> is in the print position <NUM>. In one embodiment, the card <NUM> is in the print position <NUM> when it is within the active print zone <NUM> and entirely covers the exposed surface <NUM> of the corresponding belt <NUM>, such as illustrated by card 106A, which is within the active print zone 300A and entirely covers the belt 140A, as shown in <FIG>.

At <NUM> of the method, printing is interrupted when the detected current position of the card <NUM> indicates that the card <NUM> is not in the print position. This interruption to the print operation may take on various forms. In some embodiments, the interruption in step <NUM> involves the controller <NUM> preventing the print operation from occurring in step <NUM>. Additionally, the controller <NUM> may issue an error notification that is discernible by a user of the printer <NUM>, such as a visual notification on a control panel of the printer <NUM>, an audible notification through a speaker of the printer <NUM>, or another suitable notification. In the main embodiment of the invention, the controller <NUM> takes remedial action to correct the misregistration of the card <NUM> with the print position <NUM> reloading the card <NUM> onto the belt <NUM>, such as described above with reference to <FIG>. Additionally, as discussed in greater detail below, the controller <NUM> may adjust the active print zone <NUM> of the ink jet print head <NUM> for the misregistered card <NUM>.

A card <NUM> may be considered as being in the print position <NUM> or the active print zone <NUM> of a corresponding belt <NUM> if the detected edge (<NUM>, <NUM>, <NUM> or <NUM>) of the card <NUM> is within the active print zone <NUM> and is within a predetermined threshold distance from a corresponding edge of the active print zone <NUM>. Since the active print zone <NUM> may be slightly larger than the card surface <NUM> to ensure full edge-to-edge imaging of the card <NUM>, the threshold distances may be set to ensure that the card <NUM> remains within the active print zone <NUM>. If an edge of the card <NUM> is detected outside the active print zone <NUM>, or within the active print zone <NUM> but displaced from a corresponding edge of the active print zone <NUM> by a distance that is greater than the threshold distance, the current position of the card <NUM> would indicate that the card <NUM> is not in the print position <NUM> or within the active print zone <NUM>. Also, if an edge of the card <NUM> is not detected during the movement of the sensor <NUM>, the current position would indicate that the card <NUM> is not in the print position <NUM> or an active print zone <NUM>.

The current position of the card 106A detected through the detection of either the leading edge <NUM> or the trailing edge <NUM> of the card 106A by the sensor <NUM> in step <NUM> would indicate that the card 106A is in the print position and the active print zone 300A, because the locations of the leading edge <NUM> and the trailing edge <NUM> are within the active print zone 300A and are within a threshold distance from the corresponding edges <NUM>' and <NUM>' of the active print zone 300A. However, the current position of the card 106B would not indicate that it was in the print position <NUM> or the active print zone 300B for the belt 140B based on the detection of either the leading edge <NUM> or the trailing edge <NUM> of the card 106B, because the location of the leading edge <NUM> is not within the active print zone 300B, and the trailing edge <NUM>, while within the active print zone 300B, is displaced a distance from the edge <NUM>' of the active print zone 300B that is greater than the allowed threshold distance.

Similarly, the detection of either of the side edges <NUM> and <NUM> of the card 106A by the sensor <NUM> in step <NUM> would indicate that the card 106A is in the print position <NUM> and the active print zone 300A, because the locations of the leading edges <NUM> and <NUM> are within the active print zone 300A and are within a threshold distance from the corresponding edges <NUM>' and <NUM>' of the active print zone 300A. However, the current position of the card 106B would not indicate that it was in the print position <NUM> or the active print zone 300B for the belt 140B based on the detection of either the side edge <NUM> or the side edge <NUM>, because while the location of the side edge <NUM> is within the active print zone 300B, it is displaced a distance from the corresponding edge <NUM>' of the active print zone 300B that is greater than the threshold distance, and the side edge <NUM> is not within the active print zone 300B.

Accordingly, since the current position of the card 106B detected by the sensor <NUM> would indicate that the card 106B is not in the print position <NUM> or the active print zone 300B corresponding to the belt 140B, the printing would be interrupted at <NUM> of the method, and the controller <NUM> would not perform a print operation on the cards 106A and 106B in step <NUM>. Rather, the print operation would be interrupted at step <NUM> due to the misregistration of the card 106B with its corresponding print position <NUM> and active print zone 300B. However, if the card 106B was properly registered with its print position and active print zone 300B, the controller <NUM> would proceed with the print operation on the cards 106A and 106B in step <NUM>. Also, in the event that the card 106B is removed from <FIG> and only the card 106A is being processed, the controller <NUM> would proceed with a print operation on the card 106A in step <NUM>, because the current position of the card 106A detected by the sensor <NUM> would indicate that the card 106A is in the print position <NUM> and the active print zone 300A corresponding to the belt 140A.

As mentioned above, the interruption at step <NUM> may involve corrective action by the controller <NUM> to compensate for the misregistration between a card <NUM> and the intended print position <NUM> and active print zone <NUM>. In some embodiments, this involves shifting the active print zone <NUM> to a modified active print zone that is substantially aligned with the current position of the card <NUM>. The execution of this adjustment to the location of the active print zone <NUM> may be limited to situations in which the card <NUM> is in the corresponding print position <NUM>, in which the card <NUM> may entirely cover the exposed surface <NUM> of the belt <NUM>, thereby ensuring that the print operation will not contaminate the surface <NUM> with ink.

Examples of shifting the active print zone <NUM> to compensate for misregistration between the current position of a card <NUM> and the active print zone <NUM> of the belt <NUM> on which the card <NUM> is supported are provided in <FIG>, which are simplified top plan views of a card <NUM> relative to an active print zone <NUM>. The belt <NUM> and other components are not shown in order to simplify the illustrations.

In <FIG>, the current position of the card <NUM> along the processing axis <NUM> or fast axis <NUM> is offset a distance <NUM> from the original active print zone <NUM> (dashed box). This misregistration may be compensated by the controller <NUM> by shifting the active print zone <NUM> the distance <NUM> along the processing axis <NUM> to a modified active print zone <NUM>', which is aligned with the current position of the card <NUM> along the processing axis <NUM> and fast axis <NUM>. As a result, the edges <NUM> and <NUM> of the card <NUM> are within the edges <NUM>" and <NUM>" of the modified active print zone <NUM>'. As mentioned above, the offset distance <NUM> that can be compensated by the controller <NUM> may be limited to ensure that the card <NUM> remains in the corresponding print position, in which the card entirely covers the exposed surface <NUM> of the corresponding belt <NUM>.

Similarly, in <FIG>, the current position of the card <NUM> along the slow scan axis <NUM> is offset a distance <NUM> from the original active print zone <NUM> (dashed box). This misregistration may be compensated by the controller <NUM> by shifting the active print zone <NUM> the distance <NUM> along the slow scan axis <NUM> to a modified active print zone <NUM>', which is aligned with the current position of the card <NUM> along the slow scan axis <NUM>. As a result, the edges <NUM> and <NUM> of the card <NUM> are within the edges <NUM>" and <NUM>" of the modified active print zone <NUM>'. The offset distance <NUM> along the slow scan axis <NUM> that can be compensated by the controller <NUM> may be limited to ensure that the card <NUM> remains in the corresponding print position, in which the card <NUM> may entirely cover the exposed surface <NUM> of the corresponding belt <NUM>.

After compensating for the misregistration of the card <NUM> to the active print zone <NUM> by shifting the active print zone <NUM> along the processing axis <NUM> and/or the slow scan axis <NUM> to the modified active print zone <NUM>', the method can return to step <NUM> and a print operation may be performed on the card <NUM>. Thus, this process could be used to allow a print operation to be performed on the card 106B shown in <FIG> if the card 106B was in the print position, in which the card <NUM> may entirely cover the belt 140B.

Additional embodiments address misregistration between the current position of a card <NUM> and the active print zone <NUM> in the form of a skew angle between the card <NUM> and the active print zone <NUM> or the processing axis <NUM>. <FIG> is a top plan view of the card transport <NUM> illustrating embodiments of the present disclosure, in which the current position of the card 106A is in the print position <NUM> and the active print zone 300A of the belt 140A, and the card 106B is in the print position of the belt 140B, but is at a skew angle <NUM> relative to the processing axis <NUM>. The skew angle <NUM> of the card 106B may potentially result in portions of the card 106B extending beyond the active print zone 300B, such as the corner <NUM>, as shown in <FIG>. Accordingly, the card 106B is misregistered with the active print zone 300B. Additionally, text and/or graphics within a printed image corresponding to the active print zone 300B may be undesirably cutoff or misaligned with the edges of the card 106B due to the skew angle <NUM>. Thus, even if the card 106B was contained within the active print zone 300B, the skew angle <NUM> may cause misalignment between an image printed to the card 106B and the edges of the card 106B.

In some embodiments of the method, the current position of the card <NUM> detected in step <NUM> is based on the skew angle of the card <NUM> relative to the processing axis <NUM>. This may involve the detection of the location of at least two points along an edge of the card <NUM>, such as one of the edges <NUM>, <NUM>, <NUM> or <NUM>. For example, the sensor <NUM> may be moved along a path indicated by arrow <NUM> along the processing axis <NUM> and the fast scan axis <NUM> during step <NUM> to position the sensor <NUM> at a location <NUM> to detect the position along the processing axis <NUM> of a point on the edge <NUM> of the card 106A and/or a position <NUM> to detect the position of a point on the edge <NUM> of the card 106A, as indicated in <FIG>. The sensor <NUM> may also be moved along the path <NUM> to detect a point on the edge <NUM> of the card 106B corresponding to a location <NUM> of the sensor <NUM> and/or a point on the edge <NUM> of the card 106B corresponding to a location <NUM> of the sensor <NUM>, as indicated in <FIG>. The sensor <NUM> may then be moved along a path indicated by arrow <NUM> during step <NUM> to allow the sensor <NUM> to detect the position along the processing axis <NUM> of a point on the edge <NUM> of the card 106B corresponding to a location <NUM> of the sensor <NUM> and/or a point on the edge <NUM> of the card 106B corresponding to a location <NUM> of the sensor <NUM>, and the position of a point on the edge <NUM> of the card 106A corresponding to a location <NUM> of the sensor <NUM> and/or a point on the edge <NUM> of the card 106A corresponding to a location <NUM> of the sensor <NUM>. The positions of two points on the edge <NUM> or <NUM> of the card 106A, and the positions of two points on the edge <NUM> or <NUM> of the card 106B may be used by the controller to determine the skew angle of the cards 106A and 106B.

Similarly, the skew angles of the cards 106A and 106B may be determined by detecting the positions of two points along the side edge <NUM> and/or the side edge <NUM> of the cards 106A and 106B relative to the processing axis <NUM> by moving the sensor <NUM> along the slow scan axis <NUM> in step <NUM> at different locations along the processing axis <NUM>. For example, the sensor <NUM> may be moved along the slow scan axis <NUM> across paths <NUM> and <NUM> during the moving step <NUM> to allow the sensor <NUM> to detect the positions of points at locations <NUM> and <NUM> along the edge <NUM> of the card 106A, or points at locations <NUM> and <NUM> along the edge <NUM> of the card 106A relative to the processing axis <NUM>. Likewise, the sensor <NUM> may be moved along the slow scan axis <NUM> across paths <NUM> and <NUM> during the moving step <NUM> to allow the sensor <NUM> to detect the positions along the slow scan axis <NUM> of points at locations <NUM> and <NUM> along the edge <NUM>, or points at locations <NUM> and <NUM> along the edge <NUM> of the card 106B relative to the processing axis <NUM>.

The controller <NUM> may use the locations of the two points detected along an edge of the card 106A and 106B to determine the skew angle of the cards 106A and 106B relative to the processing axis, such as the skew angle <NUM> of the card 106B. Thus, the current position of the card <NUM> detected in step <NUM> may be based upon the detected skew angles of the cards 106A and 106B, each determined through at least one of the two-point edge position measurements described above.

Embodiments of the present disclosure also include alternative techniques for detecting the skew angle of a card <NUM> relative to the processing axis <NUM>. In one example, a sensor <NUM> in the form of a camera could be used to detect the orientation of one or more edges of the card relative to the processing axis <NUM> to determine the skew angle of the card <NUM>.

In the example provided in <FIG>, the skew angle of card 106A would be approximately zero since the edges <NUM> and <NUM> of the card 106A are oriented substantially parallel to the processing axis <NUM> and the fast scan axis <NUM>, and the edges <NUM> and <NUM> are oriented substantially perpendicularly to the processing axis <NUM> and the fast scan axis <NUM>. However, the non-zero skew angle of <NUM> would be determined for the card 106B because the positions of the points along the edge <NUM> or the edge <NUM> would indicate that the edges <NUM> and <NUM> are at the skew angle <NUM> to the processing axis <NUM> and the fast scan axis <NUM>, and the positions of the points along the edge <NUM> or <NUM> would indicate that the edges <NUM> and <NUM> are at the skew angle <NUM> to a line extending perpendicularly to the processing axis <NUM> or to the slow scan axis <NUM>.

The detected current position of the card 106A in step <NUM> would allow the controller <NUM> to determine that the card 106A is in the print position <NUM> and is correctly registered with the active print zone 300A for the belt 140A. While the detected current position of the card 106B may indicate that the card 106B is registered with the print position <NUM> because the card 106B covers the exposed surface <NUM> of the belt 140B, it would also indicate that the card 106B is misregistered with the active print zone 300B due to the skew angle <NUM>. As a result, rather than performing a print operation at step <NUM> on the cards 106A and 106B, an interruption to the print operation would be triggered in step <NUM> of the method.

In some embodiments, the misregistration of a card <NUM> with an active print zone <NUM> due to a skew angle between the card <NUM> and the active print zone <NUM> or the processing axis <NUM> may be compensated for by the controller <NUM> by shifting the fast scan axis <NUM> of the gantry <NUM> from its original position of being substantially parallel to the processing axis <NUM>, to approximately the skew angle to the processing axis <NUM>. In one embodiment, this is accomplished using the gantry <NUM>, an example of which is illustrated in the simplified diagram of <FIG>.

The gantry <NUM> includes a carriage mechanism <NUM> and drive screws <NUM> and <NUM>. The carriage mechanism <NUM> includes a motor <NUM> that drives movement of the carriage <NUM> supporting the print head <NUM> and the sensor <NUM> along the fast scan axis <NUM> between ends <NUM> and <NUM> of the carriage mechanism <NUM>, which are supported by the drive screws <NUM> and <NUM>. Motors <NUM> and <NUM> respectively rotate the drive screws <NUM> and <NUM> to move the ends <NUM> and <NUM> of the carriage mechanism <NUM> along the slow scan axis <NUM>. In normal operation, the drive screws <NUM> and <NUM> are rotated by the motors <NUM> and <NUM> in a synchronous manner to maintain the desired parallel relationship between the processing axis <NUM> and the fast scan axis <NUM> of the carriage mechanism <NUM>, as indicated in phantom lines.

In one embodiment, the orientation of the carriage mechanism <NUM> and the fast scan axis <NUM> is adjusted relative to the processing axis <NUM> by the controller <NUM> using the drive screws <NUM> and <NUM> to shift the orientation of the active print zone <NUM> in better alignment with the skewed card <NUM>. For example, the skew angle <NUM> of the card 106B in <FIG> may be compensated for by driving the motor <NUM> to move the end <NUM> of the carriage mechanism <NUM> in the direction of arrow <NUM>, and/or driving the screw <NUM> using the motor <NUM> to move the end <NUM> of the carriage mechanism <NUM> in the opposing direction indicated by arrow <NUM>, to align the orientation of the fast scan axis <NUM> of the carriage mechanism <NUM> at the skew angle <NUM> relative to the processing axis <NUM>.

This results in a shift of the active print zone 300B to a modified active print zone 300B' that is in better alignment with the card 106B due to a change in the orientation of the original fast scan axis <NUM> (dashed line) to a modified fast scan axis <NUM>' that is aligned substantially parallel to the edges <NUM> and <NUM> of the card 106B, as shown in the simplified top plan view of <FIG>. As a result, the card 106B is within the modified active print zone 300B'. Additionally, the edges <NUM>" and <NUM>" of the modified active print zone 300B are substantially parallel with the edges <NUM> and <NUM> of the card 106B. These adjustments result in the card 106B being registered with the modified active print zone 300B'.

Thus, after performing the skew angle compensation described above, the method can return to step <NUM> and a print operation may commence to print an image to the card 106B, while maintaining the orientation of the carriage mechanism <NUM> with the modified fast scan axis <NUM>'. Note that this print operation may be performed when either the card 106A shown in <FIG> is not present, or is at a similar skew angle to the processing axis <NUM> as the card 106B, for example.

Thus, embodiments of the present disclosure provide solutions to the misregistration of a card <NUM> with a print position and/or an active print zone <NUM> corresponding to a belt <NUM>. In addition to the detection of different types of card misregistration, embodiments of the present disclosure operate to compensate for misregistration between a card <NUM> and an active print zone <NUM> to allow a print operation to commence on the card <NUM>. As a result, the ink jet card printer <NUM> may efficiently perform print operations due to the ability to avoid having to reload substrates, or troubleshoot and adjust mechanisms of the printer to fix card misregistration issues.

Claim 1:
A method of operating an ink jet card printer (<NUM>) having a transport belt (<NUM>), a print unit (<NUM>) including an inkjet print head (<NUM>), a sensor (<NUM>) and a gantry (<NUM>) supporting the ink jet print head (<NUM>) and the sensor (<NUM>) for movement relative to the transport belt (<NUM>), the method comprising:
loading a card (<NUM>) onto the transport belt (<NUM>) including engaging the card (<NUM>) with an exposed surface of the transport belt (<NUM>) and driving the card (<NUM>) along a processing axis (<NUM>) using the exposed surface of the transport belt (<NUM>);
moving the sensor (<NUM>) and the ink jet print head (<NUM>) relative to the card (<NUM>) using the gantry (<NUM>);
detecting a current position of the card (<NUM>) relative to the processing axis (<NUM>) using the sensor (<NUM>);
printing an image to the card (<NUM>) using the ink jet print head (<NUM>) when the detected current position of the card (<NUM>) indicates that the card (<NUM>) is supported on the transport belt (<NUM>) in a print position; and
interrupting printing an image to the card (<NUM>) using the ink jet print head (<NUM>) when the detected current position of the card (<NUM>) indicates that the card (<NUM>) is not in the print position,
wherein interrupting printing an image to the card (<NUM>) comprises:
discharging the card (<NUM>) from the transport belt (<NUM>) including driving the card (<NUM>) along the processing axis (<NUM>) using the transport belt (<NUM>);
reloading the card (<NUM>) onto the transport belt (<NUM>) including driving the card (<NUM>) along the processing axis (<NUM>) using the transport belt (<NUM>);
detecting a new current position of the card (<NUM>) relative to the processing axis (<NUM>) using the sensor (<NUM>); and
printing an image to the card (<NUM>) using the ink j et print head (<NUM>) when the detected new current position of the card (<NUM>) indicates that the card (<NUM>) is in the print position.