Sheet containing system and image forming apparatus

A sheet containing system includes a containing member, a feed device, an ascending device, and a powder applying device. The containing member has a wall portion and is to contain a sheet. The feed device feeds the sheet to an outside of the containing member. The ascending device moves up the sheet contained in the containing member toward the feed device. The powder applying device is provided in the wall portion disposed on a downstream side in the containing member in a transport direction of the sheet. The powder applying device applies powder to an end portion of the sheet on the downstream side in the transport direction of the sheet.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is based on and claims priority under 35 USC 119 from Japanese Patent Application No. 2017-172103 filed Sep. 7, 2017.

BACKGROUND

Technical Field

The present invention relates to a sheet containing system and an image forming apparatus.

SUMMARY

According to an aspect of the present invention, a sheet containing system includes a containing member, a feed device, an ascending device, and a powder applying device. The containing member has a wall portion and is to contain a sheet. The feed device feeds the sheet to an outside of the containing member. The ascending device moves up the sheet contained in the containing member toward the feed device. The powder applying device is provided in the wall portion disposed on a downstream side in the containing member in a transport direction of the sheet. The powder applying device applies powder to an end portion of the sheet on the downstream side in the transport direction of the sheet.

DETAILED DESCRIPTION

First Exemplary Embodiment

A sheet containing system and an image forming apparatus according to a first exemplary embodiment are described.

Overall Structure

FIG. 1illustrates an image forming apparatus10that includes a containing unit50serving as an example of the sheet containing system according to the present exemplary embodiment. In the following description, in front view of the image forming apparatus10, the apparatus width direction, the apparatus height direction, and the apparatus depth direction are respectively referred to as the X direction, the Y direction, and the Z direction. Furthermore, when it is required that one side and the other side are distinguished from each other in each of the X direction, the Y direction, and the Z direction, in front view of the image forming apparatus10, the upper side is referred to as the +Y side, the lower side is referred to as the −Y side, the right side is referred to as the +X side, the left side is referred to as the −X side, the rear side is referred to as the +Z side, the front side is referred to as the −Z side.

The image forming apparatus10includes the transport unit12, an image forming section14, and a fixing device40. The transport unit12transports sheets of recording paper. Each of these recording sheets serves as an example of a recording medium. The image forming section14forms with toner toner images G on the recording sheet transported by the transport unit12. The fixing device40applies heat and pressure to the toner images G so as to fix the toner images G onto the recording sheet. According to the present exemplary embodiment, the toner images G are formed on label sheets of paper P. Each of these label sheets P serves as the recording medium instead of the recording sheet. The details of the label sheet P will be described later. The following description describes the case where the label sheet P is used as the recording medium.

As illustrated inFIG. 1, the image forming section14includes image forming units20Y,20M,20C, and20K and a transfer unit30. Here, yellow (Y), magenta (M), cyan (C), and black (K) are examples of toner colors. Furthermore, the image forming section14includes a controller18that controls operation of components of the image forming units20to cause the toner images G to be formed on the label sheet P. The image forming units20perform charging, exposing, developing, and transfer steps of a known electrophotographic method as an example. In the following description, the suffixes Y, M, C, and K of the image forming units20Y,20M,20C, and20K and components included therein are omitted when distinction in accordance with the toner colors (Y, M, C, and K) is not required.

The image forming units20include respective photosensitive drums22and respective developing devices24.

The photosensitive drums22have a function of holding the toner images G developed by the developing devices24. Here, on outer circumferential surfaces of the photosensitive drums22Y,22M,22C, and22K, the toner images G of the respective colors, that is, yellow (Y), magenta (M), cyan (C), and the black (K) are formed. The photosensitive drums22each have a cylindrical shape and are each rotated about its own axis (in an arrow R1direction) by a drive device (not illustrated). The photosensitive drum22includes, for example, an aluminum base material and a photosensitive layer (not illustrated). The photosensitive layer includes an undercoating layer, a charge production layer, and a charge transport layer formed in this order on the base material.

The developing devices24have a function of developing electrostatic latent images formed on the photosensitive drums22into the respective toner images G. The developing devices24each extends in the axial direction of the photosensitive drum22.

The transfer unit30has a function of transferring through second transfer the toner images G of the respective colors onto the label sheet P after the toner images G that had been developed on the outer circumferential surfaces of the photosensitive drums22by the developing devices24have been transferred through first transfer. The transfer unit30includes a transfer belt32, first transfer rollers34for the respective colors, a drive roller36, and a second transfer roller38. Here, the transfer belt32is an example of an image holding body that holds the toner images G.

The transfer belt32is an endless belt. The first transfer rollers34and the drive roller36are disposed so as to be in contact with an inner circumferential surface of the transfer belt32. The orientation of the transfer belt32, which is inclined relative to the apparatus width direction in front view, is determined by rollers in contact with the inner circumferential surface of the transfer belt32, that is, the four first transfer rollers34, the drive roller36, a tension applying roller39, and so forth. The outer circumferential surfaces of the photosensitive drums22of the image forming units20arranged in a direction inclined relative to the apparatus width direction are in contact with a portion of an outer circumferential surface of the transfer unit30facing the lower side in the apparatus height direction. As illustrated inFIG. 1, when the drive roller36is rotated in an arrow R2direction, the transfer belt32is rotated in an arrow R3direction.

A first transfer voltage is applied to the first transfer rollers34, thereby transferring through first transfer the toner images G formed on the outer circumferential surfaces of the photosensitive drums22Y,22M,22C, and22K onto the outer circumferential surface of the transfer belt32.

The second transfer roller38has an elongated shape. The second transfer roller38is pressed by a pressure device (not illustrated) during image forming operation, thereby a nip N is formed between the second transfer roller38and the transfer belt32. A second transfer voltage is applied to the second transfer roller38, thereby transferring through second transfer the toner images G having been transferred through first transfer onto the outer circumferential surface of the transfer belt32onto the label sheet P transported by the transport unit12and passing through the nip N.

The transport unit12has a function of transporting the label sheets P contained in the containing unit50toward an output unit16. The transport unit12includes a feed roller12A, a transport roller pair12B, a transport roller pair12C, an inversion transport unit12D, and output rollers12E. The label sheet P is transported in a transport direction F through a transport path12F. In the containing unit50to be described later, a direction in which the label sheets P are moved from a containing member52to the feed roller12A and the transport roller pair12B, that is, toward the +X side is the transport direction F. Here, the feed roller12A has a function of feeding each of the label sheets P contained in the containing unit50to the outside of the containing unit50. The feed roller12A serves as an example of a feed device.

The fixing device40has a function of fixing onto the label sheet P the toner images G transferred through second transfer onto the label sheet P. The fixing device40includes a fixing roller42and a pressure roller44.

The Label Sheet

The image forming apparatus10according to the present exemplary embodiment is able to form images on the label sheet P serving as an example of the recording medium. As illustrated inFIGS. 2A and 2B, the label sheet P includes a surface material P1, a tacky layer P2, and release paper P3. The toner images G are transferred (images are formed) onto the surface of the surface material P1. The tacky layer P2includes glue applied to a rear surface of the surface material P1. The release paper P3is pasted on the tacky layer P2. Furthermore, a transfer surface S is set as a surface onto which the toner images G are transferred in the surface material P1of the label sheet P. Furthermore, the transfer surface S has an image forming region A where the images are formed and margins M where no image is formed. Examples of the margins M include, for example, a region where the toner images G are not able to be transferred, a region where the quality of the images formed therein is not guaranteed, and a region set by the controller18. The label sheet P is an example of a sheet. An end portion of the label sheet P on the downstream side in the transport direction F is defined as a leading end and an end portion of the label sheet P on the upstream side in the transport direction F is defined as a trailing end.

Here, the tacky layer P2may extend outward past the surface material P1to a surrounding region depending on the state of cutting of the label sheet P when the label sheet P is formed. Furthermore, the release paper P3may be shifted relative to the surface material P1due to warpage of the label sheet P during transportation. This may also cause the tacky layer P2to extend outward past the surface material P1to the surrounding region.

Examples of the surface material P1include fine paper, kraft paper, recycled paper, and so forth. Examples of the glue applied to the tacky layer P2include a variety of adhesives such as an acrylic adhesive, a polyester adhesive, a urethane adhesive, a silicone adhesive, a natural rubber adhesive, and a synthetic rubber adhesive.

Structures

Next, the containing unit50according to the present exemplary embodiment is described.

FIGS. 3A and 3Billustrate the containing unit50. The containing unit50includes the containing member52, a bottom plate54, and a powder applying device100. Here, the bottom plate54is an example of an ascending device.

As illustrated inFIG. 3A, the containing member52is a casing that has a recessed shape and is open at the top (+Y side). Recording media such as label sheets P contained in the containing member52are stacked one on top of another. The containing member52has wall portions52A and a bottom portion52B. The wall portions52A are arranged in a rectangular frame shape in plan view. The bottom portion52B closes a lower portion of the wall portion52A. Furthermore, in the containing member52, a groove portion52C is formed on one of the wall portions52A on the downstream side (+X side) of in the transport direction F. The groove portion52C extending in the width direction of the label sheet P (Z direction) has a rectangular shape in section. The powder applying device100is provided in the groove portion52C. The structure of the powder applying device100will be described later.

The bottom plate54is a plate-shaped member provided at the bottom portion52B of the containing member52. Here, the label sheets P contained in the containing member52are stacked one on top of another on an upper surface of the bottom plate54. The bottom plate54has a fulcrum on the upstream side (−X side) in the transport direction F and an end portion on the downstream side (+X side) in the transport direction F (referred to as “distal end” hereafter) that is upwardly movable in an arrow U direction. The bottom plate54according to the present exemplary embodiment includes a drive device (not illustrated) which moves the distal end of the bottom plate54upward in the arrow U direction. Thus, the bottom plate54is inclined relative the bottom portion52B. When the label sheets P contained in the inclined state are moved upward together with the bottom plate54, the feed roller12A is brought into contact with an uppermost one of the label sheets P in the containing member52(seeFIG. 6A). Thus, the uppermost label sheet P is transported by the feed roller12A toward the transport roller pair12B. That is, the label sheet P is guided toward the transport path12F in the transport direction F.

The bottom plate54may be moved upward by a spring member such as a coil spring instead of the drive device. In this case, the bottom plate54is moved downward along with removal (drawing) of the containing unit50from an apparatus body10A of the image forming apparatus10and held in a lowered state. Furthermore, when the holding of the lowered state has been released due to mounting of the containing unit50in the apparatus body10A, the bottom plate54is moved upward until the label sheet P is brought into contact with the feed roller12A.

The powder applying device100is provided in the containing member52and has a function of applying powder H to the leading end of each of the label sheets P. The powder applying device100according to the present exemplary embodiment is provided in the width direction of the label sheet P (Z direction) in the groove portion52C provided in the wall portion52A of the containing member52(seeFIG. 3B). The length of the powder applying device100in the width direction of the label sheet P (Z direction) is substantially equal to an inner width of the containing member52in the Z direction and equal to or larger than the width of the label sheet P, or more specifically, equal to or larger than the width of the tacky layer P2(seeFIG. 2A). This powder applying device100includes a contact portion110and a storing portion120. The contact portion110is able to be brought into contact with the label sheet P. The powder H is stored in the storing portion120.

As illustrated inFIG. 4, the storing portion120is an elongated member having a rectangular shape in section when seen in the width direction of the label sheet P. The storing portion120is formed of a sponge having an open cell structure and serving as a porous elastic body. Furthermore, the storing portion120is contained in the groove portion52C.

The contact portion110is a brush-shaped member including fibers embedded in a surface of the storing portion120closer to the inner side (−X side) of the containing member52. The powder H is held on a surface (on the −X side) of the contact portion110. As illustrated inFIG. 3A, the contact portion110projects toward the −X side on the wall portion52A on the +X side. That is, the contact portion110projects inward in the containing member52. Additionally, the contact portion110projects to such a degree that the contact portion110is brought into contact with the leading end of the label sheet P even when the leading end of the label sheet P is separated from the wall portion52A in the case where the contained label sheet P in the inclined state is moved upward together with the bottom plate54. The type of the fibers included in the contact portion110may be, for example, a chemical fiber, an animal fiber, or a vegetable fiber. It is sufficient that the fibers of the contact portion110be able to be bent.

Examples of the powder H applied to the leading end of the label sheet P by the powder applying device100include, for example, silica, polymethyl methacrylate (PMMA), zinc stearate (ZnSt), calcium carbonate, and talc. The particle size (number-average particle size) of the powder H may be set to be, for example, from 0.5 to 14 μm. When the particle size of the powder H is smaller than 0.5 μm, the powder H is likely to be sunk into the tacky layer P2of the label sheet P. Thus, it may be difficult to maintain the degree of suppression of the adherence of the glue. When the particle size of the powder H is larger than 14 μm, an initial degree of suppression of the adherence of the glue may tend to be smaller than a required degree of suppression. In addition to the above-described examples, the examples of the powder H may include a yellow (Y) toner and a clear toner.

Operations

As described above, the tacky layer P2may extend outward past the surface material P1in the label sheet P (seeFIGS. 2A and 2B). That is, the glue may extend outward to an outer peripheral portion of the transfer surface S of the label sheet P. When the label sheet P in the above-described state enters the nip N, the glue may adhere to the transfer belt32. In view of the above-described situation, the image forming apparatus10that includes the containing unit50according to the present exemplary embodiment may suppress adhering of the glue to the transfer belt32during image formation on the label sheet P. Operations according to the present exemplary embodiment are described below with reference toFIGS. 5A, 5B, 6A and 6B.

As illustrated inFIG. 5A, before the bottom plate54is moved upward, the label sheets P stacked one on top of another are contained in the containing member52in a horizontal state. At this time, the uppermost label sheet P is positioned below (−Y side) the powder applying device100. That is, since the label sheets P are separated from the contact portion110of the powder applying device100, the powder H does not adhere to the leading ends of the label sheets P. According to the present exemplary embodiment, even when a maximum number of the label sheets P are contained in the containing member52, the uppermost label sheet P is positioned below (−Y side) the powder applying device100.

Next, as illustrated inFIG. 5B, when the distal end of the bottom plate54is moved upward in the arrow U direction, the leading ends of the label sheets P are moved upward together with the bottom plate54in the arrow U direction. Consequently, the label sheets P are sequentially brought into contact with the contact portion110from the uppermost label sheet P to the label sheets P below the uppermost label sheet P. This causes the powder H contained in the contact portion110or held on the surface of the contact portion110to adhere to the glue extending outward to the leading ends of the label sheets P. Here, since the contact portion110of the powder applying device100projects inward (−X side) in the containing member52, the contact portion110is likely to be brought into contact with the leading ends of the label sheets P when the leading ends of the label sheets P are moved upward together with the bottom plate54in the arrow U direction. That is, according to the present exemplary embodiment, compared to a structure in which the contact portion110of the powder applying device100is disposed in the wall portion52A, the powder H may easily adhere to the glue extending outward to the leading ends of the label sheets P. That is, exposure of the glue may be able to be further suppressed. As illustrated inFIG. 2B, in the case where the tacky layers P2are disposed further to the trailing end sides than the release paper P3at the leading ends of the label sheets P, the tacky layers P2do not necessarily exposed from the stack of the label sheets P when the label sheets P are stacked one on top of another in the horizontal state in the containing member52. However, with the contact portion110according to the present exemplary embodiment, the fibers included in the contact portion110reach the tacky layers P2through gaps between sheets of the release paper P3. Thus, the powder H may adhere to the glue that extends past the leading ends of the label sheets P but is positioned inside the stack of the label sheets P.

Furthermore, the contact portion110, which is a brush-shaped member, is bent at a portion where the contact portion110and the label sheets P are in contact with each other when the contact portion110is brought into contact with the leading ends of the label sheets P. This allows each of the label sheets P to be fed toward the feed roller12A side (+Y side) while the movement of the label sheet P is not blocked by the contact portion110. That is, according to the present exemplary embodiment, compared to a structure in which the contact portion110is not deformed or displaced, the likelihood of the label sheet P being caught by the contact portion110when the label sheet P is brought into contact with the contact portion110may be reduced. When the contact portion110is brought into contact with the label sheets P, the contact portion110is bent, and further, the storing portion120is elastically deformed. As a result, the powder H contained in the storing portion120is supplied to the contact portion110. That is, the storing portion120according to the present exemplary embodiment is able to supply the powder H when the contact portion110is a brush-shaped member. According to the present exemplary embodiment, compared to a structure that is not provided with the storing portion120, shortage in supply of the powder H may be suppressed.

When the leading ends of the label sheets P are further moved upward in the arrow U direction, as illustrated inFIG. 6A, the feed roller12A is brought into contact with the uppermost label sheet P in the containing member52. Thus, as illustrated inFIG. 6B, the uppermost label sheet P is transported toward the transport roller pair12B when the feed roller12A is rotated. That is, the label sheet P is guided toward the transport path12F in the transport direction F.

Thus, with the containing unit50according to the present exemplary embodiment, when the label sheet P is used, the following features may be obtained compared to the structure with which the powder H is not applied to the leading end of the label sheet P. That is, according to the present exemplary embodiment, due to the upward movement of the label sheet P along with the upward movement of the bottom plate54, the powder H is able to be applied to the leading end of the label sheet P. That is, since the powder H is able to adhere to the glue extending outward to the leading end of the label sheet P, exposure of the glue at the leading end of the label sheet P may be suppressed. This may suppress adhering of the glue to the transfer belt32, and accordingly, may suppress image defects. Furthermore, since adhering of the glue to portions of the transport path12F is suppressed, transport failure may be suppressed. In order to check whether or not the exposure of the glue is suppressed at the leading end of the label sheet P, it is sufficient to check, for example, whether or not an adhering force of the glue exposed at the leading end of the label sheet P is reduced.

Furthermore, as illustrated inFIGS. 5B, 6A, and 6B, the contact portion110is brought into contact with the leading ends of the label sheets P that are stacked one on top of another. Here, the powder H may adhere to the transfer surface S at the leading end of the uppermost label sheet P that is to be brought into contact with the contact portion110first. However, the powder H is unlikely to adhere to the transfer surfaces S of the label sheets P below the uppermost label sheet P. Also with the uppermost label sheet P, when the amount of projection of the contact portion110inward (−X side) in the containing member52is equal to or smaller than the length of the margin M on the leading end side of the label sheet P, adhering of the powder H to the image forming region A where the images are formed may be suppressed.

Second Exemplary Embodiment

The powder applying device according to a second exemplary embodiment is differently structured from that of the first exemplary embodiment. The difference between the first exemplary embodiment and the second exemplary embodiment will be described. The same elements as those of the first exemplary embodiment are denoted by the same reference signs.

As illustrated inFIG. 7, a powder applying device200according to the second exemplary embodiment is provided in the width direction of the label sheet P (Z direction) in the groove portion52C of the containing member52. This powder applying device200includes a contact portion210and a storing portion220. The contact portion210has a cylindrical shape and is rotatable about the axis extending in the width direction of the label sheet P (Z direction). The powder H is stored in the storing portion220. The contact portion210has a length in the width direction of the label sheet P (Z direction) that is, in the Z direction, equal to an inner width of the containing member52and equal to or larger than width of the label sheet P. A shaft212is inserted through a central portion of the contact portion210. End portions of the shaft212in the width direction of the label sheet P (on the +Z side and the −Z side) are rotatably supported by wall portions of a container222of the storing portion220. Part of the cylindrical surface210A of the contact portion210on the −X side is exposed in the containing member52. The cylindrical surface210A serves as an example of a contact surface. The contact portion210projects to such a degree that the contact portion210is brought into contact with the leading end of the label sheet P even when the leading end of the label sheet P is separated from the wall portion52A in the case where the contained label sheet P in the inclined state is moved upward together with the bottom plate54. Although the contact portion210is formed of a sponge having an open cell structure and serving as a porous elastic body according to the present exemplary embodiment, this is not limiting as long as the powder H is able to be held and able to be applied to the leading end of the label sheet P at the cylindrical surface210A. For example, the contact portion210may be formed of brush-shaped fiber member.

The storing portion220has an opening224on the inner side of the containing member52(−X side) and the container222having a box shape elongated in the width direction of the label sheet P (Z direction). This storing portion220is contained in the groove portion52C of the containing member52. Furthermore, the contact portion210is contained in the container222. Furthermore, a cover portion226is provided so as to cover the opening224. The cover portion226has a gap228at its central portion in the Y direction. The contact portion210is disposed so as to close the gap228from which the cylindrical surface210A of the contact portion210is exposed. In other words, the cover portion226covers the contact portion210so that the cylindrical surface210A is exposed from the gap228. The cover portion226is an elastic plate member, and a peripheral portion around the gap228is pressed against the cylindrical surface210A.

Here, in the storing portion220, the contact portion210is contained in a space defined by the container222and the cover portion226, and the powder H is stored such that the powder H is in contact with the contact portion210(cylindrical surface210A). The powder H is held on the cylindrical surface210A of the contact portion210exposed from the gap228.

Operation of the powder applying device200according to the second exemplary embodiment is as follows. That is, as illustrated inFIG. 5B, when the distal end of the bottom plate54is moved upward in the arrow U direction, the leading ends of the label sheets P are brought into contact with the powder applying device200. Specifically, the leading ends of the label sheets P are brought into contact with the cylindrical surface210A of the contact portion210of the powder applying device200exposed in the containing member52. This may cause the powder H held on the cylindrical surface210A to adhere to the glue extending outward to the leading ends of the label sheets P. Furthermore, the contact portion210is rotated in the arrow U direction (an arrow R4direction illustrated inFIG. 7) when the leading ends of the label sheets P are brought into contact with the contact portion210. That is, according to the present exemplary embodiment, compared to a structure in which the contact portion210is not deformed or displaced, the likelihood of the label sheet P being caught by the powder applying device200when the label sheet P is brought into contact with the powder applying device200may be reduced. As illustrated inFIG. 7, as a result of the rotation of the contact portion210in the arrow R4direction, the powder H in the storing portion220is picked up by the contact portion210and a new portion of the cylindrical surface210A to which the powder H adheres appears in the gap228. That is, the storing portion220is able to supply the powder H when the contact portion210is a rotatable cylindrical body. According to the present exemplary embodiment, compared to a structure that is not provided with the storing portion220, shortage in supply of the powder H may be suppressed.

As illustrated inFIG. 2B, in the case where the tacky layers P2are disposed further to the trailing end sides than the release paper P3at the leading ends of the label sheets P, the tacky layers P2do not necessarily exposed from the stack of the label sheets P when the label sheets P are stacked one on top of another in the horizontal state in the containing member52. However, with the contact portion210according to the present exemplary embodiment, a layer of the powder H is formed on the cylindrical surface210A. Thus, the powder H may adhere to the glue that extends past the leading ends of the label sheets P but is positioned inside the stack of the label sheets P. Furthermore, when the contact portion210is formed of a fiber member, the fibers included in the contact portion210reach the tacky layers P2through gaps between sheets of the release paper P3. Thus, the powder H may adhere to the glue that extends past the leading ends of the label sheets P but is positioned inside the stack of the label sheets P.

Third Exemplary Embodiment

A support structure of the powder applying device according to a third exemplary embodiment is different from that of the first exemplary embodiment. The difference between the first exemplary embodiment and the third exemplary embodiment will be described. The same elements as those of the first exemplary embodiment are denoted by the same reference signs.

As illustrated inFIG. 8, the powder applying device100according to the third exemplary embodiment is supported by coil springs56. Each of the coil springs56serves as an elastic body that is an example of a pressure member. These coil springs56have a function of pressing the powder applying device100toward the label sheet P side. The plural coil springs56that are able to extend and contract in the X direction are arranged in the width direction of the label sheet P (Z direction) in the groove portion52C of the containing member52. Furthermore, the storing portion120is slidably contained in the groove portion52C. In this way, the plural coil springs56are interposed between a bottom portion of the groove portion52C (surface on the −X side) and a bottom surface of the storing portion120(surface on the +X side). The powder applying device100including the storing portion120is prevented from dropping from the groove portion52C by a stopper (not illustrated; for example, a structure in which a claw member projecting from the storing portion120is fitted into a step portion provided in the groove portion52C).

Operation of the powder applying device100according to the third exemplary embodiment is as follows. That is, as illustrated inFIG. 5B, when the distal end of the bottom plate54is moved upward in the arrow U direction, the leading ends of the label sheets P are brought into contact with the contact portion110. At this time, the powder applying device100including the contact portion110is pressed by the stack of the label sheets P, thereby the powder applying device100is moved toward the inside of the groove portion52C (+X side) resisting elastic forces of the coil springs56. Thus, although the contact portion110is pressed so as to be retracted to the groove portion52C side due to contact with the label sheets P, the contact portion110is pressed against the leading ends of the label sheets P due to the elastic forces of the coil springs56. Thus, according to the present exemplary embodiment, compared to a structure in which the powder applying device100is not supported by the coil springs56, the powder H may easily adhere to the glue extending outward to the leading ends of the label sheets P. That is, exposure of the glue may be able to be further suppressed.

Here, when the number of the label sheets P contained in the containing member52reduces, that is, the thickness of the stack of the label sheets P becomes smaller than the height of the contact portion110(length in the Y direction), the label sheets P are more easily deformed than the contact portion110. Furthermore, the likelihood of the leading ends of the label sheets P being caught by the contact portion110increases. Accordingly, when the number of the label sheets P contained in the containing member52reduces, there may be transport failure of the label sheets P such as paper jamming due to damage to the label sheets P. In order to address this, the powder applying device100including the contact portion110is movable in the X direction according to the present exemplary embodiment. Thus, even when the number of the label sheets P contained in the containing member52reduces, the powder applying device100is pressed so as to be retracted to the groove portion52C side, thereby allowing the label sheets P to be smoothly fed toward the feed roller12A side (+Y side).

Although the coil springs56are used as examples of the pressure member according to the present exemplary embodiment, this is not limiting. Instead, a plate spring may be provided in the width direction of the label sheet P (Z direction). Furthermore, since the powder applying device100itself is movable in the X direction according to the present exemplary embodiment, the contact portion110is not necessarily formed of a brush-shaped member including fibers. For example, the contact portion110may be formed of a sponge having an open cell structure and serving as a porous elastic body. Furthermore, the structure according to the present exemplary embodiment may be used for the powder applying device200according to the second exemplary embodiment.

Fourth Exemplary Embodiment

The disposition of the powder applying device according to a fourth exemplary embodiment is different from that of the first exemplary embodiment. The difference between the first exemplary embodiment and the fourth exemplary embodiment will be described. The same elements as those of the first exemplary embodiment are denoted by the same reference signs.

As illustrated inFIG. 9, a powder applying device100A according to the fourth exemplary embodiment includes the contact portion110and the storing portion120as is the case with the powder applying device100according to the first exemplary embodiment. Here, as illustrated inFIG. 3B, the powder applying device100according to the first exemplary embodiment is horizontally provided in the width direction of the label sheet P (Z direction). In contrast, as illustrated inFIG. 9, the powder applying device100A according to the fourth exemplary embodiment is provided such that an end portion of the powder applying device100A on the +Z side is disposed at a lower position (−Y side) than the position of an end portion of the powder applying device100A on the −Z side. Additionally, the powder applying device100A is provided in a groove portion that is formed such that, relative to the wall portion52A of the containing member52, an end portion of the groove portion on the +Z side is disposed at a lower position (−Y side) than the position of an end portion of the groove portion on the −Z side. According to the present exemplary embodiment, even when a maximum number of the label sheets P are contained in the containing member52, the uppermost label sheet P is positioned below (−Y side) the powder applying device100A.

The operation and the features of the powder applying device100A according to the present exemplary embodiment are as follows. That is, as illustrated inFIG. 5B, when the distal end of the bottom plate54is moved upward in the arrow U direction, the leading ends of the label sheets P start being brought into contact with the contact portion110from the +Z side. This contact position moves toward the −Z side as the distal end of the bottom plate54is moved upward. That is, when the leading ends of the label sheets P are brought into contact with the contact portion110, the label sheets P are brought into contact continuously in the width direction of the label sheet P (Z direction) instead of being brought into contact entirely in the width direction at a time. Accordingly, compared to the case where the powder applying device is horizontally provided, resistance generated when the powder H is applied may be suppressed.

Notes

Although the bottom plate54is moved upward so as to be inclined relative to the bottom portion52B in the containing unit50according to the above-described exemplary embodiments, this is not limiting. The bottom plate54may be moved upward while being parallel to the bottom portion52B.

Furthermore, although the containing unit50contained in the apparatus body10A serves as an example of the sheet containing system according to the exemplary embodiments, this is not limiting. The following structure may be used. That is, a feed unit mounted outside the apparatus body10A serves as an example of the sheet containing system, and the powder applying device100is provided in this feed unit.

Although the toner images G of the colors developed by the respective image forming units20are transferred onto the label sheet P through the transfer belt32in the above-described exemplary embodiments, this is not limiting. The toner images G may be directly transferred onto the label sheet P. Furthermore, although the image forming apparatus is for forming toner images of multiple colors according to the above-described exemplary embodiments, this is not limiting. Techniques described herein may be used for an image forming apparatus for forming toner images of a single color (for example, black (K)). In the above-described cases, the label sheet P is transported toward the photosensitive drum22serving as an example of the image holding body.

For the exemplary embodiments, a switching device may be provided. With this switching device, whether or not to use the powder applying device100or200is switched in accordance with the type of the recording medium. As the switching device, for example, a cover (shutter) may be provided on a surface of the contact portion110or210on the inner side of the containing member52. Alternatively, the powder applying device100or200may be removed and an elongated member (dummy) formed of resin may be mounted in the groove portion52C. With the switching device, application of the powder H is able to be stopped when recording paper used as the recording medium is, for example, plain paper. That is, the containing unit50(containing member52) is also usable for other types of sheets such as plain paper instead of being dedicated to the label sheets P.

For the exemplary embodiments, the powder applying device100or200may be irreplaceable. In this case, the storing portion120or220has such a capacity that the powder H is not exhausted in the life of the apparatus. Instead, for the exemplary embodiments, the powder applying device100or200may be replaceable. In this case, only the storing portion120may be replaced with a new storing portion120for the powder applying device100according to the first and third exemplary embodiments and for the powder applying device100A according to the fourth exemplary embodiments, or the powder applying device100or100A itself may be replaced with a new powder applying device100or100A. Furthermore, regarding the powder applying device200according to the second exemplary embodiment, the storing portion220may be replenished with the powder H, or the powder applying device200itself may be replaced with a new powder applying device200.

Although the sheet onto which the toner images G are transferred is the label sheet P that includes the tacky layer P2to which the glue is applied according to the exemplary embodiments, the sheet usable with the techniques herein is not limited to the label sheet P. For example, the techniques herein may be used for coated paper formed by coating the surface of plain paper with resin or the like. Also with the coated paper, image defects may occur or the cleaning performance may be adversely affected when the resin on the surface of the coated paper is removed and adheres to the transfer belt32. Accordingly, by causing the powder H to adhere to the leading end of the coated paper in the transport direction F, adhering of the resin on the surface of the coated paper to the transfer belt32may be suppressed.