Paper supply device and image forming apparatus having the same

A paper supply device and an image forming apparatus, capable of always maintaining a constant pickup force regardless of the amount of loaded sheets of paper. The paper supply device includes a paper supply cassette, a pickup unit to pick up the paper, a paper supply plate and a press spring to bias the paper toward the pickup unit, a first restraining device to restrain the paper supply plate and to release the restraint of the paper supply plate, a second restraining device to permit the pickup unit to move vertically when the pickup unit picks up the paper and restricts the vertical movement of the pickup unit when the pickup unit does not pick up the paper, and an elastic member to bias the pickup unit toward the paper to provide the pickup unit with a pickup force when the pickup unit picks up the paper.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims all benefits accruing under 35 U.S.C. §119 from Korean Patent Application No. 2007-70523, filed in the Korean Intellectual Property Office on Jul. 13, 2007, the disclosure of which is incorporated herein by reference.

BACKGROUND OF THE INVENTION

1. Field of the Invention

Aspects of the present invention relate to a paper supply device to supply printable medium to a main body of an image forming apparatus, and an image forming apparatus having the same.

2. Related Art

An image forming apparatus, such as a copying machine, a fax machine or a printer, includes a paper supply device to supply paper into a main body. Typically, the paper supply device picks up the loaded paper sheet by sheet, and supplies the paper into a main body of the image forming apparatus. As used herein, “paper” refers to any medium onto which an image may be printed, including paper, thermal paper, and transparent film.

Japanese Laid-Open Patent Publication No. 2006-8343 (published on Jan. 12, 2006) discloses an image forming apparatus with a paper supply device. The paper supply device of the disclosed image forming apparatus includes a pickup roller to pick up the paper loaded in a paper cassette, a paper supply roller, and a spring to push up a paper supply plate loaded with the paper toward the pickup roller. The paper supply device further includes a lifting device, which, if the amount of loaded paper decreases as the paper is supplied to the main body, moves the paper supply plate toward the pickup roller so that the uppermost paper contacts the pickup roller.

The lifting device includes a planetary gear coupled to the paper supply plate, an internal gear engaged with the planetary gear and coupled to a frame of the paper supply device, a sun gear engaged with the planetary gear, a ratchet rotating coaxially with the sun gear, and a restraining member restraining or releasing the ratchet. The restraining member includes a locking lever that is latched by the ratchet, a spring biasing the locking lever, and a solenoid device that releases the locking lever from the ratchet.

The pickup roller and the paper supply roller are rotatably supported by a pickup frame in the main body. The pickup frame moves up and down within a predetermined region so that a position of the pickup roller changes according to a height of the loaded sheets of paper. A height sensor is mounted near the pickup frame to sense a height of the pickup frame. The solenoid device of the restraining member is controlled based on a sensing signal from the height sensor for the position of the pickup frame. If the pickup roller moves down, the solenoid device operates the locking lever to be released from the ratchet, and the paper supply plate is biased upward by an elastic force of the spring mounted below. The planetary gear moves up by revolving around the sun gear by the rotation of the sun gear, thereby moving up the paper supply plate.

The loaded sheets of paper move up by the lifting force of the paper supply plate. If the uppermost paper pushes up the pickup roller, the pickup frame also moves up. If the pickup frame moves up, the height sensor senses the movement of the pickup frame, and the operation of the solenoid device is stopped, so that the locking lever restrains the ratchet. If the ratchet is restrained, the rising of the paper supply plate is stopped.

The above conventional paper supply device is configured such that when the paper is picked up, the rising force created by the spring pushing up the paper supply plate is applied to the pickup roller through the loaded sheets of paper. However, because the rising force changes according to the amount of loaded sheets of paper on the paper supply plate, a pickup force is not constant. Because the rising force of the spring changes according to the amount of loaded sheets of paper and the weight of the loaded sheets of paper, the pickup force is not constant.

Further, because the lifting device to push up the paper supply plate includes the internal gear, the planetary gear, the sun gear, the ratchet, the locking lever, the solenoid device, the height sensor, etc., the above conventional paper supply device has a great number of components and complicated constitution of the components.

SUMMARY OF THE INVENTION

Aspect of the present invention provide a paper supply device and an image forming apparatus having the same that is capable of always maintaining a constant pickup force regardless of the amount of loaded sheets of paper.

Additional aspects of the invention provide a paper supply device and an image forming apparatus having the same that is capable of more simplifying a device of adjusting a height of a paper supply plate than a conventional device.

According to an aspect of the invention, a paper supply device is provided. The paper supply device comprises a paper supply cassette to load a printable medium; a pickup unit to pick up the printable medium loaded in the paper supply cassette sheet by sheet; a paper supply plate and a press spring arranged to bias the loaded printable medium toward the pickup unit; at least one first restraining device to restrain the paper supply plate when the pickup unit picks up the printable medium and to release the paper supply plate when the pickup unit does not pick up the printable medium; a second restraining device to permit the pickup unit to move up and down when the pickup unit picks up the printable medium and to restrict the up/down movement of the pickup unit when the pickup unit does not pick up the printable medium; and an elastic member to bias the pickup unit toward the printable medium so as to provide the pickup unit with a pickup force when the pickup unit picks up the printable medium.

According to another aspect of the present invention, the pickup unit includes a rotating shaft rotating by a driving source, a paper supply roller coupled to the rotating shaft, a pickup roller disposed above the printable medium at a distance from the paper supply roller to pick up the printable medium in conjunction with the paper supply roller, a pickup frame to support the pickup roller and to rotate on the rotating shaft so as to move the pickup roller up and down, and a lifting member connected to the pickup frame or a shaft of the pickup roller and biased toward the paper by the elastic member so as to move the pickup roller up and down.

According to another aspect of the present invention, the first restraining device includes a first rotating cam coupled to the rotating shaft, a lifting cam to move up and down by operation of the first rotating cam, a first restoring spring to bias the lifting cam toward the first rotating cam, an advancing/retreating member to advance and retreat in a direction perpendicular to the lifting cam according to the up/down movement of the lifting cam and having a tooth part extending vertically to restrain the paper supply plate, and a latching part provided at the paper supply plate so as to be latched by or released from the tooth part according to operation of the advancing/retreating member so as to restrain or release the paper supply plate.

According to another aspect of the present invention, the lifting cam includes at least one inclined slot having an inclination with respect to an up/down moving direction, and the advancing/retreating member includes at least one protrusion that is fitted into the inclined slot.

According to another aspect of the present invention, the first restraining device includes a plurality of first restraining devices respectively provided at two sides of the paper supply cassette.

According to another aspect of the present invention, the second restraining device includes a second rotating cam coupled to the rotating shaft, a restraining member to advance and retreat by operation of the second rotating cam and having a restraining protrusion to restrain or release the lifting member, a second restoring spring to bias the restraining member toward the second rotating cam, and a restraining recess formed at the lifting member so as to allow the restraining protrusion to fit into the restraining recess to be latched.

According to another aspect of the present invention, the restraining recess is provided with inclined guide surfaces formed at an opening of the restraining recess while being inclined so as to have an expanded opening to ensure smooth fitting of the restraining protrusion.

According to another aspect of the present invention, the pickup unit includes a plurality of gears to transmit a rotational force of the paper supply roller to the pickup roller, and oneway clutches provided at a coupling portion of the rotating shaft and the paper supply roller and a connecting portion of the pickup roller and the plurality of gears.

According to another aspect of the invention, an image forming apparatus is provided. The image forming apparatus comprises an image forming unit to form an image onto a printable medium; and a paper supply device to supply the printable medium to the image forming unit, the paper supply device including a paper supply cassette to load the printable medium, a pickup unit to pick up the printable medium loaded in the paper supply cassette sheet by sheet, a paper supply plate and a press spring to bias the loaded printable medium toward the pickup unit, a first restraining device to restrain the paper supply plate when the pickup unit picks up the printable medium and release the paper supply plate when the pickup unit does not pick up the printable medium, a second restraining device to permit the pickup unit to move up and down when the pickup unit picks up the printable medium and to restrict the movement of the pickup unit when the pickup unit does not pick up the printable medium, and an elastic member to bias the pickup unit toward the printable medium so as to provide the pickup unit with a pickup force when the pickup unit picks up the printable medium.

In addition to the example embodiments and aspects as described above, further aspects and embodiments will be apparent by reference to the drawings and by study of the following descriptions.

DETAILED DESCRIPTION OF THE EMBODIMENTS

FIG. 1shows a schematic constitution of an image forming apparatus100according to an example embodiment of the present invention. The image forming apparatus100includes a paper supply device50to store paper P therein, a feeding unit10to feed the paper P, an image forming unit20to form an image on the paper P, a fusing unit30to fuse the transferred image to the paper, and a paper discharge unit40to discharge the paper. According to other aspects of the invention, the image forming apparatus may include additional and/or different units. Similarly, the functionality of two or more of the above units may be combined into a single component. In addition, although described herein with respect to paper, any printable medium may be used, such as paper, thermal paper, or transparent film.

A pickup unit60picks up the paper loaded in the paper supply device50sheet by sheet, and supplies the paper toward the feeding unit10. A detailed constitution of the paper supply device50will be described later.

The feeding unit10feeds the paper picked up by the pickup unit to a print path A. The feeding unit10includes a feeding roller11, a feeding backup roller12, a feeding guide13that forms the print path A, a register roller14, and a register backup roller15, which registers the front end of the fed paper.

The image forming unit20includes a photosensitive roller21, a charge roller22, and a laser scanning unit (LSU)23. The photosensitive roller21is positioned in the print path A. The charge roller22charges the photosensitive roller21. The laser scanning unit (LSU)23irradiates a laser beam to the charged photosensitive roller21according to an image signal so as to form an electrostatic latent image on the surface of the photosensitive roller21. The image forming unit20further includes a developing roller24and a transfer roller25. The developing roller24supplies a developer to the electrostatic latent image formed on the photosensitive roller21to form a visible image. The transfer roller25transfers the visible image formed on the photosensitive roller21onto the paper. The photosensitive roller21charged by the charge roller22assumes a negative charge. The electrostatic latent image is formed on the surface of the photosensitive roller21by the laser beam irradiated from the LSU23. The developing roller24supplies the developer having a negative charge to the electrostatic latent image on the photosensitive roller21to form the visible image. The transfer roller25having a positive charge transfers the developer adhering to the photosensitive roller21onto the paper.

The fusing unit30is disposed near an outlet of the print path A. The fusing unit30includes a heat roller31and a press roller32. While the paper passes between the heat roller31and the press roller32, the fusing unit30applies heat and pressure to the developer (image) transferred onto the paper so that the developer is fused onto the paper.

The paper discharge unit40feeds the paper, which has passed by the fusing unit30, to a paper discharge part3provided on an upper portion of a main body1. The paper discharge unit40includes a paper guide member41that is mounted above the fusing unit30and guides the paper to the paper discharge part3, and plural discharge rollers42and43that are disposed in a discharge path B.

As shown inFIG. 2, the paper supply device50provided in a lower portion of the main body1includes a paper supply cassette51that is removably mounted in the lower portion of the main body1, and a pickup unit60provided above the paper supply cassette51. Because the pickup unit60is fixedly mounted in the main body1, the pickup unit60remains inside the main body1, even when removing the paper supply cassette51from the main body1to add paper.

A paper supply plate52and plural press springs53are mounted inside the paper supply cassette51. The press springs53are disposed under the paper supply plate52to bias the paper supply plate52toward the pickup unit60. One end of the paper supply plate52is hingedly coupled to the paper supply cassette51by hinge pins52a. The other end portion of the paper supply plate52is supported by the press springs53from below. Since the paper loaded on the paper supply plate52is applied with a rising force by the press springs53, the paper is pushed up toward the pickup unit60, and can be picked up sheet by sheet by the pickup unit60.

As shown inFIGS. 2 and 3, the pickup unit60includes a rotating shaft61mounted in the main body1, a paper supply roller62coupled to the rotating shaft61, a pickup roller63disposed above the paper at a distance from the paper supply roller62, and a pickup frame64supporting the pickup roller63and rotating on the rotating shaft61. The pickup roller63can rotate via a supporting shaft65, both ends of which are coupled to the pickup frame64. The pickup unit60further includes plural gears66,67, and68, which transmit a rotational force applied to the paper supply roller62through the rotating shaft61to the pickup roller63. As shown inFIG. 3, the gears include a driving gear66coupled to the paper supply roller62, a driven gear68mounted adjacent to the pickup roller63, and an intermediate gear67connecting the driving gear66and the driven gear68. The intermediate gear67is rotatably mounted to the pickup frame64.

If the rotating shaft61rotates by a driving source (not shown), the pickup roller63rotates with the paper supply roller62and picks up the paper loaded in the paper supply cassette51. As shown inFIG. 6, since the paper loaded in the paper supply cassette51contacts the pickup roller63, the paper is picked up sheet by sheet by the rotation of the pickup roller63, and is fed toward the feeding roller11by the operation of the paper supply roller62. Although the driving source to rotate the rotating shaft61for the pickup operation is not shown, the driving source may be configured as, for example, a motor mounted in the main body1.

Returning toFIG. 3, a first one-way clutch69is mounted to a coupling portion of the rotating shaft61and the paper supply roller62, and a second oneway clutch70is mounted to a connecting portion of the pickup roller63and the driven gear68. With this configuration, even if the paper supply roller62and the pickup roller63rotate while the paper goes out of the paper supply cassette51by the operation of the feeding roller11after the pickup operation, the rotation of the rollers62and63is not transmitted to the rotating shaft61. When the rotating shaft61rotates for the pickup operation, the first one-way clutch69transmits the rotational force of the rotating shaft61to the paper supply roller62, and the second one-way clutch70transmits the rotational force of the driven gear68, which rotates by the operation of the paper supply roller62, to the pickup roller63. However, while the picked-up paper goes out of the paper supply cassette51after the pickup operation, the first and second one-way clutches69and70permit the paper supply roller62and the pickup roller63to rotate independently of the rotation of the rotating shaft61. This is to secure smooth feeding of the paper. Since the constitution of the one-way clutch is well known, an explanation thereof will be omitted.

As shown inFIG. 2, the pickup unit60further includes a lifting member71and an elastic member72. The lifting member71extends upward from the supporting shaft65so as to move up and down with the pickup roller63. The elastic member72biases the lifting member71downward. The lifting member71extends upward by a predetermined length. An upper portion of the lifting member71is slidably inserted into a supporting part73provided in the main body1. The lifting member71may be coupled to the pickup frame64, adjacent to the pickup roller63. The elastic member72may be configured as a coil spring that biases the lifting member71downward, and is disposed between an outer top surface of the lifting member71and the supporting part73. If the up/down movement of the pickup unit60is not restrained by a second restraining device90(which will be described later), the elastic member72moves the pickup roller63down by the elastic force so that the pickup roller63can contact the upper surface of the paper, thereby providing the pickup roller63with the pickup force. Here, a pressure for picking up the paper is determined by the elastic force of the elastic member72.

As shown inFIG. 2, the paper supply device50further includes a first restraining device80and a second restraining device90. The first restraining device90restrains the paper supply plate52when the pickup roller63picks up the paper and releases the restraint of the paper supply plate52when the pickup roller63does not pick up the paper. The second restraining device90permits the pickup roller63to move up and down when the pickup roller63picks up the paper and restricts the up/down movement of the pickup roller63when the pickup roller63does not pick up the paper.

The first restraining device80includes a first rotating cam81, a lifting cam82, a first restoring spring83, an advancing/retreating member84, and a latching part85. The lifting cam82is coupled to the rotating shaft61and rotates with the rotating shaft61. The lifting cam82moves up and down by the operation of the first rotating cam81. The first restoring spring83biases the lifting cam82upwardly toward the first rotating cam81. The advancing/retreating member84advances and retreats in a direction perpendicular to the lifting cam82according to the up/down movement of the lifting cam82, and has a tooth part84ato restrain the paper supply plate52. The latching part85is provided at the paper supply plate52to be latched by or released from the tooth part84aaccording to the advancing and retreating of the advancing/retreating member84.

The lifting cam82is provided with a contact portion82aprovided at an upper portion to come into contact with the first rotating cam81and plural inclined slots82bpositioned while opposing the advancing/retreating member84and having an inclination with respect to the up/down moving direction. An upper end of the first restoring spring83is coupled to a lower portion of the lifting cam82. A lower end of the first restoring spring83is coupled to the paper supply cassette51, thereby pushing up the lifting cam82.

The advancing/retreating member84is coupled to a side surface of the paper supply cassette51so as to advance and retreat along a rail86provided on the side surface of the paper supply cassette51, in the direction perpendicular to the up/down moving direction of the lifting cam82. The advancing/retreating member84is provided with plural protrusions84bthat are fitted into the inclined slots82bof the lifting cam82. When the lifting cam82moves up and down, the advancing/retreating member84advances and retreats via the protrusions84b, guided by the inclined slots82b. The tooth part84aof the advancing/retreating member84extends vertically long enough for the paper supply plate52to be latched thereto at an ascending position and a descending position. The paper supply plate52is provided with an extending portion88that extends outward through an opening portion87formed at the side surface of the paper supply cassette51. The latching part85is coupled to the extending portion88. The opening portion87formed at the side surface of the paper supply cassette51extends vertically long enough for the extending portion88to move up and down according to the up/down movement of the paper supply plate52.

The first restraining device80operates as follows. If the lifting cam82is pressed by the first rotating cam81, the lifting cam82moves down. If the lifting cam82moves down, the protrusions84bof the advancing/retreating member84are guided by the inclined slots82b, and the advancing/retreating member84moves away from the latching part85. The latching part85is released from the tooth part84aso that the paper supply plate52can move upward. If the paper supply plate52moves up, the sheets of paper loaded on the paper supply plate52also ascend, so that the uppermost paper contacts the pickup roller63and comes to a state capable of being picked up. If the pressing of the first rotating cam81on the lifting cam82is released, the lifting cam82moves up by the elastic force of the first restoring spring83. The protrusions84bof the advancing/retreating member84are guided by the inclined slots82bin the reverse direction, and the advancing/retreating member84moves toward the latching part85. The latching part85is latched by the tooth part84a, and the paper supply plate52is restrained. In other words, the up/down movement of the paper supply plate52is restricted. As shown inFIG. 2, the first restraining device80can be provided in pairs at both sides of the paper supply cassette51, so as to simultaneously restrain or release both sides of the paper supply plate52.

The second restraining device90includes a second rotating cam91coupled to the rotating shaft61, a restraining member92, a second restoring spring94, and a restraining recess95. The restraining member92advances and retreats by the operation of the second rotating cam91and has a restraining protrusion93to restrain or release the lifting member71. The second restoring spring94biases the restraining member92toward the second rotating cam91. The restraining recess95formed at the lifting member71, into which the restraining protrusion93is fitted to be latched thereby.

The second rotating cam91is mounted on the rotating shaft61, adjacent to the paper supply roller62. The second rotating cam91is formed in a semicircular shape or a fan shape so as to make the restraining member92advance and retreat by the rotation. The restraining member92is supported in the main body1so as to advance and retreat substantially in a paper supplying direction. Although not shown, an additional supporting member to support the restraining member92may be provided in the main body1. The restraining member92is provided with a contact portion92a, which is in contact with the second rotating cam91, at one end portion. The restraining protrusion93is provided at the other end of the restraining member92. The second restoring spring94is configured as a tension spring. One end of the second restoring spring94is coupled to the restraining member92, and the other end is coupled to a spring supporting part97mounted in the main body1.

The restraining recess95formed at the lifting member71has an opening at one side so that when the restraining member92advances and retreats, the restraining protrusion93can fit into the restraining recess95to be latched thereby or released from the restraining recess95. In order to secure the smooth fitting of the restraining protrusion93into the restraining recess95, the restraining recess95may be provided with inclined guide surfaces95a, as shown inFIG. 5. The inclined guide surfaces95aare formed at upper and lower portions of the opening of the restraining recess95, and are inclined so as to have an expanded opening. Besides the function of guiding the fitting of the restraining protrusion93into the restraining recess95, the inclined guide surfaces95aalso have a function of moving the pickup roller63to an initial set position by guiding the lifting member71to ascend or descend when the restraining protrusion93restrains the lifting member71.

Hereinafter, the operation of the paper supply device according to an example embodiment of present invention will be described. As shown inFIG. 4, when the paper supply cassette51is removed from the main body1to so as to be loaded with additional paper, the lifting cam82of the first restraining device80separates from the first rotating cam81, and the lifting cam82moves up by the elastic force of the first restoring spring83. If the lifting cam82moves up, the advancing/retreating member84moves toward the latching part85. Thus, since the latching part85of the paper supply plate52is latched by the tooth part84aof the advancing/retreating member84, the paper supply plate52is restrained so long as an external force is not applied. After adding additional paper to the paper supply cassette51, if pushing down the sheets of paper, the paper supply plate52moves down. While the latching part85of the paper supply plate52is restrained by the tooth part84a, if the external force is applied, the tooth part84ais pushed away from the latching part85. Once the paper supply plate52moves down, since the latching part85is latched again by the tooth part84a, the paper supply plate52does not move up.

As shown inFIG. 5, after installing the paper supply cassette51in the main body1after supplementing the sheets of paper in the paper supply cassette51, the lifting cam82is pushed down by the first rotating cam81. Since the restraint of the paper supply plate52is released by the tooth part84aof the advancing/retreating member84being separated from the latching part85of the paper supply plate52, the paper supply plate52and the sheets of paper ascend. The restraining protrusion93of the restraining member92fits into the restraining recess95of the lifting member71and restrains the lifting member71, preventing the pickup roller63from moving up and down. Accordingly, the uppermost paper comes into contact with the pickup roller63, and does not ascend further. The paper comes to a pickup standby state.

As shown inFIG. 6, when the rotating shaft61rotates to pick up the paper, the paper supply roller62and the pickup roller63rotate, and the first rotating cam81and the second rotating cam91also rotate. Since the pressing of the first rotating cam81on the lifting cam82is released, the lifting cam82moves up, and the paper supply plate52is restrained by the ascending of the lifting cam82. As soon as the paper supply plate52is restrained, the second rotating cam91pushes the restraining member92so that the restraining protrusion93separates from the restraining recess95of the lifting member71, thereby releasing the restraint of the lifting member71. Since the lifting member71is now capable of moving up and down, the elastic force of the elastic member72functions as the pickup force. In other words, the pressing force of the elastic member72on the pickup roller63becomes the pickup force. As described above, since the paper supply plate52is restrained at the moment the paper is picked up, the rising force of the press springs53has no influence on the pickup operation, and the elastic force of the elastic member72functions as the pickup force. Accordingly, the pickup force can be maintained constant regardless of the amount of loaded sheets of paper.

After performing the pickup operation, the first rotating cam81and the second rotating cam91rotate to the state shown inFIG. 5. Since the second rotating cam91does not press the restraining member92, the restraining member92moves toward the second rotating cam91by the elastic force of the second restoring spring94. The restraining protrusion93fits into the restraining recess95of the lifting member71, and restrains the lifting member71. When the restraining protrusion93is fitted into the restraining recess95, since the inclined guide surfaces95aformed at the opening of the restraining recess95guide the restraining protrusion93, the restraining protrusion93can be fitted into the restraining recess95smoothly. Further, although the lifting member71is in a state that the lifting member71slightly moves up or down from the initial position, since the restraining protrusion93pushes up or pulls down the lifting member71while the restraining protrusion93is guided by the inclined guide surfaces95a, the lifting member71is returned to the initial set position. Accordingly, the pickup roller63is positioned at the initial height.

As shown inFIG. 5, after the pickup operation, the first rotating cam81presses the lifting cam82again, and the lifting cam82moves down. The advancing/retreating member84moves away from the latching part85, and the restraint of the paper supply plate52is released. Accordingly, the paper ascends with the paper supply plate52.

As apparent from the above description, the paper supply device according to aspects of the present invention can maintain a constant paper pickup force. The moment the paper is picked up, the paper supply plate is restrained by the first restraining device, and the pickup roller of the pickup unit comes to a state capable of moving up and down. Accordingly, the rising force by the press springs has no influence on the pickup operation, and only the elastic force of the elastic member functions as the pickup force. In other words, the pickup force can be always maintained constant regardless of the amount of loaded sheets of paper.

Further, the paper supply device according to aspects of the present invention can more simplify the device for adjusting the height of the paper supply plate than a conventional device, because the first restraining device has the relatively simple constitution of the first rotating cam, the lifting cam, the advancing/retreating member having the tooth part, etc.

While there have been illustrated and described what are considered to be example embodiments of the present invention, it will be understood by those skilled in the art and as technology develops that various changes and modifications, may be made, and equivalents may be substituted for elements thereof without departing from the true scope of the present invention. Many modifications, permutations, additions and sub-combinations may be made to adapt the teachings of the present invention to a particular situation without departing from the scope thereof. For example, the image forming apparatus may be a printer, a facsimile machine, a copier, a multifunction device, or other device capable of forming an image onto a printable medium. As discussed above, although aspects of the present invention may be used with paper, and the various components of the apparatus described above are described in terms of paper, any printable medium may be employed. The various components used in aspects of the present invention may be composed of any suitable material. Accordingly, it is intended, therefore, that the present invention not be limited to the various example embodiments disclosed, but that the present invention includes all embodiments falling within the scope of the appended claims.