Patent Description:
<CIT> discloses a transfer-paper transport device in which a recording head having a light-emitting element array and an image-forming system is moved at a constant speed in a substantially generatrix direction of a photoconductor drum rotating at a constant speed to helically scan the photoconductor drum to form an electrostatic latent image, and a toner image obtained by developing this image is transferred to a transfer paper.

In some known image forming apparatuses, an image forming unit for forming a toner image on a recording medium and a feed path along which the recording medium to be transported toward the image forming unit passes are arranged side-by-side in the horizontal direction. Also in some cases, the image forming unit and a discharge path along which a recording medium having a toner image formed thereon and to be discharged from the image forming unit to the outside of the apparatus body passes are arranged side-by-side in the horizontal direction. In these image forming apparatuses, because the feed path and the discharge path are located away from each other in the horizontal direction, the area occupied by the feed path and the discharge path in the horizontal direction is large.

Accordingly, it is an object of the present disclosure to reduce the area occupied by the feed path and the discharge path in the horizontal direction, compared with a case where the feed path along which the recording medium to be transported to the image forming unit passes and the discharge path along which the recording medium to be discharged from the image forming unit to the outside of the apparatus body passes are located away from each other in the horizontal direction.

The present invention is provided in the appended claims. The following disclosure serves a better understanding of the present invention. The following first, fourth and sixth aspects define features of claim <NUM>, whereas the other aspects define optional features according to preferred embodiments. According to a first aspect of the present disclosure, there is provided an image forming apparatus including, among other features: an apparatus body; an image forming unit that forms a toner image on a recording medium; a first transport part that transports the recording medium to the image forming unit along a feed path extending from one side toward the other side in the horizontal direction, the feed path being a path along which the recording medium transported by the first transport part passes, and that includes a portion extending toward the one side beyond the image forming unit; and a second transport part that transports the recording medium from the image forming unit to the outside of the apparatus body along a discharge path extending from the other side toward one side in the horizontal direction and that includes a portion extending toward the one side beyond the image forming unit, the discharge path and the feed path at least partially overlapping each other in the vertical direction.

According to a second aspect of the present disclosure, the discharge path may be disposed above the feed path in the vertical direction.

According to a third aspect of the present disclosure, the image forming apparatus according to the second aspect may further include a storage part for storing a recording medium to be fed to the feed path, the storage part being disposed below the discharge path in the vertical direction.

According to a fourth aspect of the present disclosure, the image forming apparatus further includes a third transport part that transports the recording medium along a reversing path splitting from the discharge path at an intermediate portion thereof, extending from the other side toward the one side in the horizontal direction, extending from the one side toward the other side in the horizontal direction, and joining the feed path at an intermediate portion thereof. The reversing path is disposed between the feed path and the discharge path in the vertical direction.

According to a fifth aspect of the present disclosure, in the image forming apparatus according to any one of the first to third aspects the third transport part is configured such that the recording medium to be fed to the feed path is reversed.

According to a sixth aspect of the present disclosure, the image forming apparatus further includes a measurement part. The third transport part transports the recording medium from the other side toward the one side in the horizontal direction, may stop the transportation of the recording medium, and then transports the recording medium from the one side toward the other side in the horizontal direction. The measurement part measures the dimensions of the recording medium stopped by the third transport part.

According to a seventh aspect of the present disclosure, in the image forming apparatus according to any one of the fourth to sixth aspects, the portion of the feed path extending toward the one side beyond the image forming unit, the portion of the discharge path extending toward the one side beyond the image forming unit, and the third transport part may overlap one another in the vertical direction at a position shifted from the image forming unit in the horizontal direction.

According to an eighth aspect of the present disclosure, in the image forming apparatus according to the seventh aspect, the apparatus body may include a plurality of housings, and the feed path, the discharge path, and the reversing path may be disposed in the same housing.

According to a ninth aspect of the present disclosure, in the image forming apparatus according to any one of the fourth to eighth aspects, the reversing path may include a changing path in which a recording-medium transport direction is reversed and that is disposed below the top of the image forming unit in the vertical direction.

According to a tenth aspect of the present disclosure, in the image forming apparatus according to any one of the first to ninth aspects, the first transport part may overlap the image forming unit in the vertical direction, and the second transport part may not overlap the image forming unit in the vertical direction.

In the image forming apparatus according to the first aspect of the present disclosure, compared with a case where the feed path along which the recording medium to be transported to the image forming unit passes and the discharge path along which the recording medium to be discharged from the image forming unit to the outside of the apparatus body passes are located away from each other in the horizontal direction, the area occupied by the feed path and the discharge path in the horizontal direction is small.

In the image forming apparatus according to the second aspect of the present disclosure, compared with a case where the discharge path is disposed below the feed path, the position of the output part onto which the recording medium is discharged to the outside of the apparatus body is high.

In the image forming apparatus according to the third aspect of the present disclosure, compared with a case where the storage part and the discharge path are located away from each other in the horizontal direction, the area occupied by the storage part and the discharge path in the horizontal direction is small.

In the image forming apparatus according to the fourth aspect of the present disclosure, compared with a case where the reversing path and the area between the feed path and the discharge path are located away from each other in the horizontal direction, the area between the feed path and the discharge path is efficiently used.

In the image forming apparatus according to the fifth aspect of the present disclosure, compared with a case where the reversing path and the area between the feed path and the discharge path are located away from each other in the horizontal direction, the area between the feed path and the discharge path is efficiently used.

In the image forming apparatus according to the sixth aspect of the present disclosure, the transportation of the recording medium does not need to be stopped only for measurement.

In the image forming apparatus according to the seventh aspect of the present disclosure, the height of the image forming apparatus body does not increase, compared with a case where a portion of the feed path extending toward one side beyond the image forming unit, a portion in the discharge path extending toward one side beyond the image forming unit, and the third transport part overlap the image forming unit in the vertical direction.

In the image forming apparatus according to the eighth aspect of the present disclosure, the adjustment of the reversing path at the time of installing the image forming apparatus is simple, compared with a case where the reversing path is disposed in a housing different from the housing in which the feed path and the discharge path are disposed.

In the image forming apparatus according to the ninth aspect of the present disclosure, the height of the image forming apparatus body does not increase, compared with a case where the changing path is disposed above the top of the image forming unit in the vertical direction.

In the image forming apparatus according to the tenth aspect of the present disclosure, the height of the image forming apparatus body does not increase, compared with a case where the first transport part and the second transport part overlap the image forming unit in the vertical direction.

Exemplary embodiment of the present disclosure will be described in detail based on the following figures, wherein:.

Referring to <FIG>, an example image forming apparatus according to an exemplary embodiment of the present disclosure will be described. The arrows H, W, and D in the figures represent the top-bottom direction (vertical direction), the width direction (horizontal direction), and the depth direction (horizontal direction) of the image forming apparatus.

An image forming apparatus <NUM> according to this exemplary embodiment electrophotographically forms a toner image on a sheet member P, serving as a recording medium. As shown in <FIG>, the image forming apparatus <NUM> includes storage parts <NUM>, a paper feed mechanism <NUM>, an image forming unit <NUM>, a paper output mechanism <NUM>, an output part <NUM>, a reversing mechanism <NUM>, and a controller <NUM> that controls these components. The image forming apparatus <NUM> also includes an apparatus body <NUM> that accommodates these components. The apparatus body <NUM> includes three substantially rectangular-parallelepiped-shaped housings disposed side-by-side in the width direction. The three housings include a housing 14a, a housing 14b, and a housing 14c in this order from one side (left side) in the width direction. The housing 14a is lower than the housing 14b in the vertical direction. Thus, the upper portion of the side surface on one side (left side) of the housing 14b in the width direction is exposed.

The storage parts <NUM> accommodate sheet members P. The image forming apparatus <NUM> includes four storage parts <NUM>. The sheet members P are selectively sent out from the four storage parts <NUM>.

In this exemplary embodiment, three storage parts <NUM> are disposed side-by-side in the width direction, and one storage part <NUM> is disposed above the storage part <NUM> that is disposed at one end (left end) in the width direction, among the three storage parts <NUM>. In other words, two storage parts <NUM> are disposed one on top of the other in the vertical direction, and two storage parts <NUM> are disposed side-by-side in the width direction, on the other side (right side), in the width direction, of the storage part <NUM> that is located on the lower side among the two storage parts <NUM>.

For ease of explanation, the storage part <NUM> disposed at one end (left end) in the width direction, among the three storage parts <NUM> arranged side-by-side in the width direction, is called a storage part 50A, the storage part <NUM> disposed above the storage part 50A is called a storage part 50B, the storage part <NUM> disposed beside the storage part 50A is called a storage part 50C, and the storage part <NUM> disposed to the right of the storage part 50C is called a storage part 50D. When there is no need to distinguish between the storage parts <NUM>, the letters A, B, C, and D are omitted.

The storage parts 50A and 50B are disposed in the housing 14a. The storage parts 50C and 50D are disposed in the housing 14b.

The storage parts <NUM> each include a loading part <NUM> in which sheet members P are loaded, and a feed-out roller <NUM> that feeds out the top sheet member P in the loading part <NUM> to the feed path <NUM>.

Furthermore, feed-out paths <NUM>, along which a sheet member P sent out from the loading parts <NUM> by the feed-out rollers <NUM> passes, extend from the storage parts <NUM>, and terminal ends of the feed-out paths <NUM> join the feed path <NUM>, along which a sheet member P transported to the image forming unit <NUM> passes.

The paper feed mechanism <NUM> transports a sheet member P accommodated in a storage part <NUM> to a chain gripper <NUM> provided in a fixing device <NUM> of the image forming unit <NUM>.

More specifically, as shown in <FIG>, the paper feed mechanism <NUM> includes multiple transport rollers <NUM> for transporting the sheet member P along the feed path <NUM>. The details of the paper feed mechanism <NUM> will be described below.

The image forming unit <NUM> electrophotographically forms an image on a sheet member P. As shown in <FIG>, the image forming unit <NUM> is disposed to the other side (right side) of the storage parts <NUM> in the width direction. The image forming unit <NUM> is disposed in the housing 14c. The image forming unit <NUM> includes toner-image forming units <NUM> that form toner images, a transfer device <NUM> that transfers the toner images formed by the toner-image forming units <NUM> to a sheet member P, and the fixing device <NUM> that fixes the toner images to the sheet member P.

There are multiple toner-image forming units <NUM> that form different color toner images. The image forming unit <NUM> includes a total of four toner-image forming units <NUM>, which correspond to yellow (Y), magenta (M), cyan (C), and black (K). The letters (Y), (M), (C), and (K) shown in <FIG> are suffixed to the components corresponding to these colors. When there is no need to distinguish between the colors Y, M, C, and K, these letters are omitted.

The toner-image forming units 20Y, <NUM>, 20C, and <NUM> have basically the same configuration except for the toners used.

As shown in <FIG>, the toner-image forming units 20Y, <NUM>, 20C, and <NUM> are arranged in a line along an inclined portion of a transfer belt <NUM> provided in the transfer device <NUM>.

As shown in <FIG>, each toner-image forming unit <NUM> includes a photoconductor drum <NUM> (photoconductor) that rotates in the direction of arrow A02, and a charger <NUM> that charges the photoconductor drum <NUM>. The toner-image forming unit <NUM> further includes an exposure device <NUM> that exposes the photoconductor drum <NUM> charged by the charger <NUM> to form an electrostatic latent image, and a developing device <NUM> that develops the electrostatic latent image with toner to form a toner image.

The transfer device <NUM> first-transfers, in a superposed manner, the toner images formed on the photoconductor drums <NUM> corresponding to the respective colors to an intermediate transfer body and then second-transfers the superposed toner image to a sheet member P. More specifically, as shown in <FIG>, the transfer device <NUM> includes: the transfer belt <NUM>, serving as the intermediate transfer body; multiple rollers <NUM>; first transfer rollers <NUM>; a second transfer roller <NUM>; and a removal part (not shown).

The transfer belt <NUM> is an endless belt stretched over the multiple rollers <NUM> in a substantially inverted triangular orientation. The toner-image forming units 20Y, <NUM>, 20C, and <NUM> are arranged in a line along the inclined portion on the other side (right side) of the transfer belt <NUM> in the width direction. The transfer belt <NUM> revolves in the direction of arrow B when at least one of the multiple rollers <NUM> is rotationally driven.

Furthermore, in the description below, among the multiple rollers <NUM>, the roller <NUM> that is disposed so as to outwardly push an inclined portion of the transfer belt <NUM> on one side (left side) in the width direction is called a roller 32a, and the roller <NUM> over which a portion of the transfer belt <NUM> on one side in the width direction is stretched is called a roller 32b.

The first transfer rollers <NUM> are opposed to the photoconductor drums <NUM> corresponding to the respective colors with the transfer belt <NUM> therebetween. The first transfer rollers <NUM> transfer the toner images formed on the photoconductor drums <NUM> to the transfer belt <NUM> at first transfer positions T (see <FIG>) between the photoconductor drums <NUM> and the first transfer rollers <NUM>.

The second transfer roller <NUM> is opposed to the roller 32a with the transfer belt <NUM> therebetween. The second transfer roller <NUM> transfers the toner image transferred to the transfer belt <NUM> to a sheet member P at a second transfer position NT between the transfer belt <NUM> and the second transfer roller <NUM>.

The removal part (not shown) is disposed on the opposite side of the transfer belt <NUM> from the roller 32b to remove a material deposited on the transfer belt <NUM>.

The fixing device <NUM> fixes the toner image transferred to the sheet member P by the transfer device <NUM> to the sheet member P.

As shown in <FIG>, the fixing device <NUM> includes: the chain gripper <NUM>; a preheater <NUM> that heats, in a non-contact manner, the toner image transferred to the sheet member P; a heater <NUM> that comes into contact with the sheet member P to heat the toner image; and a blowing unit <NUM>.

The chain gripper <NUM> includes a pair of chains <NUM>, leading-end holding parts <NUM> that hold the leading ends of sheet members P, and pairs of sprockets <NUM>, <NUM>, and <NUM>.

As shown in <FIG>, the chains <NUM> are endless chains and are located at a distance from each other in the depth direction. As shown in <FIG>, the chains <NUM> are wound on: the pair of sprockets <NUM> (see <FIG>), which are disposed at the ends of the second transfer roller <NUM> in the axial direction and have axes extending in the depth direction; the pair of sprockets <NUM> (see <FIG>), which are disposed at one end and the other end of a pressure roller <NUM> (described below) in the axial direction and have axes extending in the depth direction; and the pair of sprockets <NUM>, which are located at a distance from each other in the depth direction.

Furthermore, the sprockets <NUM> (see <FIG>) at the ends of the pressure roller <NUM> and the sprockets <NUM> (see <FIG>) at the ends of the second transfer roller <NUM> are disposed such that no other sprockets therebetween. When viewed in the depth direction, the sprockets <NUM> are disposed to one side (left side) of the sprockets <NUM> in the depth direction and above the sprockets <NUM>.

Furthermore, when viewed in the depth direction, the pair of sprockets <NUM> are disposed below the sprockets <NUM> and <NUM>, to on one side of the sprockets <NUM> in the width direction, and to the other side of the sprockets <NUM> in the width direction. Furthermore, a transport roller (not shown) that is coaxial with the pair of sprockets <NUM> is disposed between the pair of sprockets <NUM>.

As described, the pair of sprockets <NUM> are disposed below the sprockets <NUM> and <NUM>.

As shown in <FIG>, each leading-end holding part <NUM> includes an attachment member <NUM> extending in the depth direction, and grippers <NUM> attached to the attachment member <NUM>. The ends of the leading-end holding part <NUM> in the depth direction are attached to the chains <NUM>.

The leading-end holding parts <NUM> are disposed at predetermined intervals in the circumferential direction (revolve direction) of the chains <NUM> (see <FIG>).

The grippers <NUM> are attached to the attachment member <NUM> at predetermined intervals in the depth direction. The grippers <NUM> hold the leading end of a sheet member P. More specifically, the grippers <NUM> have jaws 76a. The attachment member <NUM> has a contact part 75a (see <FIG>) with which the jaws 76a come into contact.

The grippers <NUM> hold a sheet member P by pinching the leading end of the sheet member P between the jaws 76a and the contact part 75a. In the grippers <NUM>, for example, the jaws 76a are pressed against the contact part 75a by springs or the like, and the jaws 76a are brought toward and away from the contact part 75a by the effect of cams or the like.

In this configuration, when a rotational force is transmitted to any one of the multiple sprockets <NUM>, <NUM>, and <NUM> shown in <FIG>, the chains <NUM> revolve in the direction of arrow C so as to move from the sprockets <NUM> side toward the sprockets <NUM> side.

Furthermore, when a leading-end holding part <NUM> attached to the chains <NUM> reaches a receiving position RE at the bottom of the sprockets <NUM>, the grippers <NUM> of the leading-end holding part <NUM> pinch the leading end of the sheet member P transported along the feed path <NUM> by the transport rollers <NUM>, thus receiving and holding the sheet member P. The chains <NUM> revolving in the direction of arrow C transport the sheet member P held by the leading-end holding part <NUM> to the second transfer position NT, allow the sheet member P to face the preheater <NUM>, and then transport the sheet member P toward the heater <NUM>. At a send-out position SE immediately after the heater <NUM>, the leading-end holding part <NUM> releases the leading end of the sheet member P, and the chain gripper <NUM> sends the sheet member P to a discharge path <NUM> (described below).

As shown in <FIG>, the preheater <NUM> is disposed so as to face the top surface of the sheet member P that is being transported, on the downstream side of the second transfer position NT in the transport direction of the sheet member P (hereinbelow, the "sheet transport direction"). The preheater <NUM> includes a reflection member <NUM>, multiple infrared heaters <NUM> (hereinbelow, "heaters <NUM>"), and a wire screen <NUM>.

The reflection member <NUM> is made of an aluminum plate in the shape of a shallow box that is open on the side facing the sheet member P that is being transported. In other words, when viewed in the width direction, the reflection member <NUM> has a U shape that is open on the side facing the sheet member P that is being transported. The heaters <NUM> are cylindrical infrared heaters extending in the depth direction. The heaters <NUM> are arranged side-by-side in the sheet transport direction. The wire screen <NUM> is fixed to the edge of the reflection member <NUM> with fixing members (not shown) to divide the inside of the reflection member <NUM> from the outside.

In this configuration, the preheater <NUM> heats, in a non-contact manner and from the thickness direction of the sheet member P, the sheet member P transported by the revolving chains <NUM>. Heating the sheet member P softens the toner of the toner image transferred to the sheet member P.

As shown in <FIG>, the blowing unit <NUM> is disposed so as to oppose the preheater <NUM> in the thickness direction of the sheet member P that is being transported, and the sheet member P that is being transported passes between the blowing unit <NUM> and the preheater <NUM>. As shown in <FIG>, the blowing unit <NUM> includes multiple fans <NUM> arranged in the width direction of the sheet member P that is being transported and the sheet transport direction.

In this configuration, the orientation of the sheet member P that is being transported is stabilized by the fans <NUM> blowing air at the sheet member P.

As shown in <FIG>, the heater <NUM> is disposed downstream of the preheater <NUM> in the sheet transport direction.

As shown in <FIG>, the heater <NUM> includes a heating roller <NUM> that comes into contact with the sheet member P that is being transported to heat the sheet member P, a pressure roller <NUM> that presses the sheet member P against the heating roller <NUM>, and a driven roller <NUM> that is rotated by the heating roller <NUM>.

The heating roller <NUM> comes into contact with the upper side of the sheet member P that is being transported. The heating roller <NUM> extends in the depth direction such that the axial direction thereof is parallel to the depth direction. The heating roller <NUM> has, at the ends thereof in the depth direction, shafts 139a extending in the depth direction and support members 139b for supporting the shafts 139a.

The driven roller <NUM> is disposed on the opposite side of the heating roller <NUM> from the sheet member P that is being transported, and extends in the depth direction such that the axial direction thereof is parallel to the depth direction. The driven roller <NUM> has a heater (not shown). In this configuration, the driven roller <NUM> is rotated by the heating roller <NUM>. The driven roller <NUM> heats the heating roller <NUM>.

The pressure roller <NUM> is opposed to the heating roller <NUM> with the sheet member P that is being transported therebetween. The pressure roller <NUM> comes into contact with the lower side of the sheet member P that is being transported, and extends in the depth direction such that the axial direction thereof is parallel to the depth direction. Furthermore, as shown in <FIG>, the pressure roller <NUM> has, in the outer circumferential surface thereof, a recess 140a extending in the depth direction. When a sheet member P passes between the pressure roller <NUM> and the heating roller <NUM>, the leading-end holding part <NUM> gripping the leading end of the sheet member P is accommodated in the recess 140a.

As shown in <FIG>, a pair of shafts <NUM> having a smaller diameter than the pressure roller <NUM> and extending in the axial direction are formed at both ends of the pressure roller <NUM> in the depth direction.

The heater <NUM> includes a pair of support members <NUM> for supporting the pressure roller <NUM>, and urging members <NUM> for urging the pressure roller <NUM> toward the heating roller <NUM> with the support members <NUM> therebetween. The support members <NUM> are disposed so as to rotatably support the pair of shafts <NUM> of the pressure roller <NUM> from below.

In this configuration, the urging members <NUM> urge the pressure roller <NUM> toward the heating roller <NUM>, so that the pressure roller <NUM> presses the sheet member P against the heating roller <NUM>. Furthermore, the pressure roller <NUM> is rotated by receiving a rotational force transmitted from a driving member (not shown). The rotating pressure roller <NUM> rotates the heating roller <NUM>, and the rotating heating roller <NUM> rotates the driven roller <NUM>. As a result of the heating roller <NUM> and the pressure roller <NUM> nipping and transporting a sheet member P to which a toner image has been transferred, the toner image is heated and fixed to the sheet member P.

The paper output mechanism <NUM> discharges the sheet member P, sent out from the send-out position SE in the image forming unit <NUM>, from a discharge port provided in the side surface of the housing 14b near the housing 14a. In this exemplary embodiment, the paper output mechanism <NUM> transports the sheet member P sent out from the send-out position SE in the image forming unit <NUM> to the output part <NUM> provided outside the housing 14a.

More specifically, as shown in <FIG>, the paper output mechanism <NUM> includes multiple transport rollers <NUM> for transporting a sheet member P along the discharge path <NUM>, and a cooling unit <NUM> for cooling the sheet member P while transporting the sheet member P along the discharge path <NUM>. The paper output mechanism <NUM> will be described in detail below.

The sheet member P transported by the paper output mechanism <NUM> is output on the output part <NUM>. As shown in <FIG>, the output part <NUM> is disposed outside the housing 14a, above the two vertically stacked storage parts <NUM>.

The reversing mechanism <NUM> switches the top surface and back surface of the sheet member P. As shown in <FIG>, the reversing mechanism <NUM> includes multiple changing rollers <NUM> for transporting the sheet member P along a reversing path <NUM>, and a transport roller <NUM>. The reversing mechanism <NUM> will be described in detail below.

In the image forming apparatus <NUM> shown in <FIG>, a toner image is formed on a sheet member P as follows. First, the chargers <NUM> corresponding to the respective colors, shown in <FIG>, uniformly and negatively charge the surfaces of the photoconductor drums <NUM> corresponding to the respective colors to a predetermined electric potential. Next, the exposure devices <NUM> radiate the exposure light on the surfaces of the charged photoconductor drums <NUM> on the basis of externally input image data to form electrostatic latent images.

As a result, the electrostatic latent images corresponding to the image data are formed on the surfaces of the photoconductor drums <NUM>. The developing devices <NUM> corresponding to the respective colors develop the electrostatic latent images into visible toner images. Furthermore, the first transfer rollers <NUM> of the transfer device <NUM>, as shown in <FIG>, transfer the toner images formed on the surfaces of the photoconductor drums <NUM> to the transfer belt <NUM> at the first transfer positions T.

A sheet member P sent out from a storage part <NUM> (see <FIG>) to the feed path <NUM> by the feed-out roller <NUM> is transported by the transport rollers <NUM> and is passed to a leading-end holding part <NUM> of the chain gripper <NUM> at the receiving position RE, shown in <FIG>, to be transported. The sheet member P is transported toward the second transfer position NT by the chain gripper <NUM>. At the second transfer position NT, the sheet member P is nipped and transported between the transfer belt <NUM> and the second transfer roller <NUM>, and thus, the toner image on the surface of the transfer belt <NUM> is transferred to the surface of the sheet member P.

The fixing device <NUM> fixes the toner image transferred to the top surface of the sheet member P to the sheet member P, and the sheet member P transported by the chain gripper <NUM> is sent out to the discharge path <NUM> at the send-out position SE. The sheet member P sent out to the discharge path <NUM>, as shown in <FIG>, is cooled by being transported by the cooling unit <NUM> and is transported by the transport rollers <NUM>. The sheet member P is then discharged onto the output part <NUM> outside the housing 14a.

When a toner image is to be formed on the back surface of a sheet member P, the sheet member P that has passed through the cooling unit <NUM> is sent out the reversing path <NUM> from an intermediate portion of the discharge path <NUM> and is transported along the reversing path <NUM>. This way, the sheet member P is reversed. The reversed sheet member P is fed to an intermediate portion of the feed path <NUM>. Then, the above-described process is performed again to form a toner image on the back surface of the sheet member P.

Next, the paper feed mechanism <NUM>, the paper output mechanism <NUM>, the reversing mechanism <NUM>, and the like will be described.

The paper feed mechanism <NUM> transports a sheet member P accommodated in a storage part <NUM> to the receiving position RE of the image forming unit <NUM>. As shown in <FIG> and <FIG>, the paper feed mechanism <NUM> is disposed to one side (left side) of the receiving position RE in the image forming unit <NUM> in the width direction.

Furthermore, the paper feed mechanism <NUM> includes multiple transport rollers <NUM> for transporting the sheet member P along the feed path <NUM>, along which a sheet member P transported to the receiving position RE from the storage part <NUM> passes. The transport rollers <NUM> are an example of a first transport part. The transport rollers <NUM> are disposed in the housings 14a, 14b, and 14c.

As shown in <FIG> and <FIG>, the feed path <NUM> is a path along which a sheet member P transported to the receiving position RE from a storage part <NUM> passes and is a path extending from one side toward the other side in the width direction (horizontal direction) while changing the position thereof in the top-bottom direction. In other words, the feed path <NUM> extends in the width direction such that a sheet member P is transported from one side toward the other side in the width direction by the transport rollers <NUM>. In still other words, the feed path <NUM> extends from one side toward the other side in the width direction of the image forming apparatus <NUM> so as to pass the sheet member P to the image forming unit <NUM> from one side in the width direction, at the receiving position RE. More specifically, there are two portions of the feed path <NUM>, namely, a portion extending from the storage parts 50A and 50B in the housing 14a and a portion extending from the storage parts 50C and 50D in the housing 14b. The two portions of the feed path <NUM> join into one in the housing 14b and extend to the receiving position RE in the image forming unit <NUM> in the housing 14c. More specifically, the feed path <NUM> is disposed in the housing 14a, the housing 14b, and the housing 14c. In other words, the portion of the feed path <NUM> extending from the storage parts 50C and 50D is disposed in the housings 14b and 14c, and the portion of the feed path <NUM> extending from the storage parts 50A and 50B in the housing 14a is disposed in the housings 14a, 14b, and 14c. In still other words, a portion of the feed path <NUM> is disposed in the housing 14a, another portion of the feed path <NUM> is disposed in the housing 14b, and another portion of the feed path <NUM> is disposed in the housing 14c.

In this exemplary embodiment, the feed path <NUM> extends from one side toward the other side in the width direction without changing the transport direction vertically upward or downward at an intermediate portion of the feed path <NUM>. The feed path <NUM> has a portion that does not overlap the image forming unit <NUM>, in particular, the fixing device <NUM>, in the vertical direction on the upstream side in the sheet transport direction. Specifically, this upstream portion of the feed path <NUM> in the sheet transport direction is an example of a portion of the feed path extending toward one side beyond the image forming unit. A portion of the feed path <NUM> on other side, extending from one side toward the other side in the width direction, that is, the portion near the image forming unit <NUM>, overlaps the image forming unit <NUM>, in particular, the fixing device <NUM>, in the vertical direction.

The "feed path" as used herein is a transport path along which a sheet member P transported to the receiving position RE from a storage part <NUM> passes and along which the sheet member P is transported until the sheet member P is passed to any of the components of the image forming unit <NUM>.

In this configuration, the feed-out roller <NUM> of a storage part <NUM> feeds the top sheet member P of the sheet members P loaded in the loading part <NUM> to the feed path <NUM> through the feed-out path <NUM>. The multiple transport rollers <NUM> transport the sheet member P fed to the feed path <NUM> to the receiving position RE.

The paper output mechanism <NUM> transports the sheet member P sent out from the send-out position SE in the image forming unit <NUM> to the output part <NUM> provided outside the housing 14a. As shown in <FIG>, the paper output mechanism <NUM> is disposed to one side (left side) in the width direction of the send-out position SE in the image forming unit <NUM>. More specifically, the paper output mechanism <NUM> is disposed in the housing 14b.

Furthermore, the paper output mechanism <NUM> includes multiple transport rollers <NUM> for transporting a sheet member P along the discharge path <NUM>, along which the sheet member P transported from the send-out position SE to the output part <NUM> passes, and the cooling unit <NUM> for cooling the sheet member P while transporting. The cooling unit <NUM> and the multiple transport rollers <NUM> are arranged in this order from the upstream side to the downstream side in the sheet transport direction.

The discharge path <NUM> is a path along which a sheet member P transported from the send-out position SE in the image forming unit <NUM> toward the output part <NUM> provided outside the housing 14a passes, and extends from the other side toward one side in the width direction (horizontal direction). In other words, the discharge path <NUM> extends in the width direction so as to transport the sheet member P from the other side toward one side in the width direction. In still other words, the discharge path <NUM> extends from the other side toward one side in the width direction from the send-out position SE, at which the discharge path <NUM> receives the sheet member P. More specifically, the discharge path <NUM> extends from the send-out position SE in the housing 14c toward the housing 14b in the width direction. Specifically, the discharge path <NUM> is disposed in the housing 14b and the housing 14c. In other words, a portion of the discharge path <NUM> is disposed in the housing 14a, and a portion of the discharge path <NUM> is disposed in the housing 14b.

In this exemplary embodiment, the discharge path <NUM> extends from the other side toward one side in the width direction without changing the transport direction vertically upward or downward at an intermediate portion.

Furthermore, the discharge path <NUM> is disposed above the feed path <NUM> in the top-bottom direction (vertical direction), and the discharge path <NUM> and the feed path <NUM> at least partially overlap each other in the top-bottom direction. Furthermore, the discharge path <NUM> is disposed above the storage parts 50C and 50D accommodating sheet members P in the top-bottom direction. In other words, the storage parts 50C and 50D are disposed below the discharge path <NUM> in the top-bottom direction. The discharge path <NUM> is provided at a position not overlapping the fixing device <NUM> in the vertical direction. In other words, the discharge path <NUM> is disposed at a position shifted from the image forming unit <NUM> in the horizontal direction so as not to overlap the image forming unit <NUM> in the vertical direction. More specifically, the discharge path <NUM> has a portion extending toward one side in the width direction beyond the image forming unit <NUM>.

Herein, the "discharge path" is a transport path along which a sheet member P to which a toner image has been formed is discharged to the outside of the housing 14a passes and is a transport path along which the sheet member P that has been sent out from any of the components of the image forming unit <NUM> passes before being discharged to the output part <NUM>.

As shown in <FIG>, the cooling unit <NUM> is disposed along the discharge path <NUM> so as to receive the sheet member P to which a toner image has been fixed by the fixing device <NUM>.

As shown in <FIG>, the cooling unit <NUM> includes two rollers 90a arranged side-by-side in the width direction and an endless belt 90b stretched over the two rollers 90a. The top surface of the endless belt 90b extends along the discharge path <NUM>. The cooling unit <NUM> also includes a cooling fan 90c that blows air at the lower surface of the belt 90b to cool down the belt 90b, and rollers 90d opposed to the two rollers 90a with the discharge path <NUM> and the belt 90b therebetween. The cooling unit <NUM> is an example of a second transport part.

As shown in <FIG>, multiple transport rollers <NUM> are provided along the discharge path <NUM>, on the downstream side of the cooling unit <NUM> in the sheet transport direction. The transport rollers <NUM> are an example of the second transport part.

In this configuration, one of the two rollers 90a receives a rotational force from a driving member (not shown) and rotates. As a result, the belt 90b cooled by the cooling fan 90c revolves in the direction indicated by the arrow (counterclockwise), rotating the rollers 90d in a driven manner. The revolving belt 90b and the rollers 90d rotated by the belt 90b nip and transport the sheet member P. As a result, the sheet member P is cooled. Then, the cooling unit <NUM> passes the sheet member P to the transport rollers <NUM>, and the transport rollers <NUM> transport the sheet member P along the discharge path <NUM> and discharge the sheet member P onto the output part <NUM>.

The reversing mechanism <NUM> receives the sheet member P transported along the discharge path <NUM> from an intermediate portion of the discharge path <NUM>, reverses the sheet member P, and then guides the sheet member P to the intermediate portion of the feed path <NUM>. As shown in <FIG>, the reversing mechanism <NUM> is disposed to one side (left side) of the image forming unit <NUM> in the width direction, between the paper feed mechanism <NUM> and the paper output mechanism <NUM> in the top-bottom direction. The reversing mechanism <NUM> is disposed in the housing 14b.

The reversing mechanism <NUM> includes: the changing rollers <NUM> and the transport roller <NUM>, which transport the sheet member P along the reversing path <NUM>, which is split from the discharge path <NUM> at an intermediate portion thereof and joins the feed path <NUM> at an intermediate portion thereof; a switching member <NUM>; and a guide member <NUM>. The changing rollers <NUM> and the transport roller <NUM> are an example of the third transport part.

As shown in <FIG>, the reversing path <NUM> includes: a branch path 44a that is split from the discharge path <NUM> at a portion (G01 in <FIG>) on the downstream side of the cooling unit <NUM> in the sheet transport direction and that extends from the other side toward one side in the width direction; a changing path 44b extending from the other side toward one side in the width direction from the end of the branch path 44a and in which the sheet transport direction is reversed; and a joining path 44c extending from one side toward the other side in the width direction from the end of the changing path 44b separately from the branch path 44a and joining an intermediate portion (G02 in <FIG>) of the feed path <NUM>. The reversing path <NUM> is disposed in the housing 14b.

In this exemplary embodiment, the reversing path <NUM> extends in the width direction without changing the transport direction upward or downward at an intermediate portion. The position of the changing path 44b of the reversing path <NUM> in the vertical direction is lower than that of the image forming unit <NUM>. More specifically, the changing path 44b is disposed below the top of the image forming unit <NUM> in the vertical direction. Furthermore, the feed path <NUM>, the discharge path <NUM>, and the reversing path <NUM> are disposed so as to overlap one another in the vertical direction, without overlapping the image forming unit <NUM> in the vertical direction. In other words, a portion of the feed path <NUM> extending toward one side beyond the image forming unit <NUM>, a portion in the discharge path <NUM> extending toward one side beyond the image forming unit <NUM>, and the third transport part overlap one another in the vertical direction, at a position shifted from the image forming unit <NUM> in the horizontal direction.

Herein, the "reversing path <NUM>" is a transport path in which a sheet member P to be fed to the feed path <NUM> is reversed and is a transport path that is split from the discharge path <NUM> at an intermediate portion thereof and joins the feed path <NUM> at an intermediate portion thereof.

As shown in <FIG>, there are two changing rollers <NUM> disposed at the ends of the changing path 44b. The two changing rollers <NUM> receive a sheet member P transported from the branch path 44a to the changing path 44b and reverses the transport direction of the sheet member P. More specifically, the changing rollers <NUM> receive the sheet member P transported from the branch path 44a to the changing path 44b while rotating in one direction, and then rotate in the other direction to send out the sheet member P from the branch path 44a to the joining path 44c.

The transport roller <NUM> is disposed in the joining path 44c. The transport roller <NUM> receives the sheet member P transported in the opposite direction and sent out from the changing path 44b to the joining path 44c, and sends out the sheet member P to the intermediate portion of the feed path <NUM>.

As shown in <FIG>, the switching member <NUM> is disposed at a portion where the branch path 44a is split from the discharge path <NUM> at the intermediate portion thereof (G01 in <FIG>). The switching member <NUM> determines whether the sheet member P cooled by the cooling unit <NUM> is transported along the discharge path <NUM> or is fed to the branch path 44a.

The guide member <NUM> is disposed at a portion (G03 in <FIG>) where the changing path 44b and the joining path 44c join. The guide member <NUM> guides the sheet member P, whose transport direction has been reversed in the changing path 44b, toward the joining path 44c.

In this configuration, when a toner image is to be formed on the back surface of a sheet member P having a toner image on the top surface thereof, the switching member <NUM> guides the sheet member P transported along the discharge path <NUM> with the toner image formed on the top surface thereof from the intermediate portion of the discharge path <NUM> to the branch path 44a. The changing rollers <NUM> receive the sheet member P transported from the branch path 44a to the changing path 44b while rotating in one direction, and then rotate in the other direction to reverse the sheet transport direction. More specifically, when the changing rollers <NUM> rotating in one direction rotate in the other direction, the changing rollers <NUM> rotating in one direction temporarily stop and then rotate in the other direction. In other words, after the transportation of the sheet member P is stopped in the changing path 44b, the sheet transport direction is reversed.

The guide member <NUM> guides the sheet member P, whose transport direction has been reversed in the changing path 44b, to the joining path 44c. The transport roller <NUM> receives the sheet member P transported from the changing path 44b to the joining path 44c and guides the sheet member P to the intermediate portion of the feed path <NUM>.

The image forming apparatus <NUM> includes measurement parts <NUM> for measuring the dimensions of the sheet member P stopped in the changing path 44b. In this exemplary embodiment, when the trailing end of the sheet member P has passed through the branch path 44a, the transportation of the sheet member P is stopped.

As shown in <FIG>, the measurement parts <NUM> include a pair of detection parts 180a for detecting the position of a leading edge P01 of a sheet member P that has been stopped, a pair of detection parts 180b for detecting the position of a trailing end P02 of the sheet member P, a detection part 180c for detecting the position of one side edge P03 of the sheet member P, and a detection part 180d for detecting the position of the other side edge P04 of the sheet member P.

The detection parts 180a, 180b, 180c, and 180d are known optical sensors. The pair of detection parts 180a are arranged side-by-side in the depth direction, and the pair of detection parts 180b are arranged side-by-side in the depth direction.

In this configuration, the measurement parts <NUM> measure the dimensions of a sheet member P on the basis of the detection results obtained by the detection parts 180a, 180b, 180c, and 180d. The controller <NUM> adjusts the position of a toner image to be transferred to the sheet member P such that the distances between the edges of the toner image and the edges of the sheet member P are the same across all the edges.

Next, the operation of the relevant part configuration will be described in comparison with an image forming apparatus <NUM> according to a comparison example. First, the configuration of the image forming apparatus <NUM> according to the comparison example will be described below, focusing on the difference from the image forming apparatus <NUM>.

As shown in <FIG>, the image forming apparatus <NUM> includes storage parts <NUM>, a paper feed mechanism <NUM>, an image forming unit <NUM>, the paper output mechanism <NUM>, the output part <NUM>, and a reversing mechanism <NUM>.

As shown in <FIG>, the storage parts <NUM> are disposed to the other side of the image forming unit <NUM> in the width direction. The image forming apparatus <NUM> includes four storage parts <NUM>. Three storage parts <NUM> are disposed side-by-side in the width direction, and one storage part <NUM> is disposed above the storage part <NUM> that is located to the extreme other side (right side) in the width direction, among the three storage parts <NUM>.

As shown in <FIG>, the paper feed mechanism <NUM> is disposed to the other side (right side) of the receiving position RE in the image forming unit <NUM> in the width direction.

Furthermore, the paper feed mechanism <NUM> includes multiple transport rollers <NUM> for transporting a sheet member P along the feed path <NUM>, along which a sheet member P transported to the receiving position RE passes. The feed path <NUM> extends from the other side toward one side in the width direction. In other words, the feed path <NUM> extends from the other side toward one side in the horizontal direction.

The image forming unit <NUM> includes the toner-image forming units <NUM>, the transfer device <NUM>, and a fixing device <NUM>. As shown in <FIG>, the fixing device <NUM> includes a chain gripper <NUM>, the preheater <NUM>, the heater <NUM>, and the blowing unit <NUM>. The chain gripper <NUM> includes the pair of chains <NUM>, the leading-end holding parts <NUM> that hold the leading ends of sheet members P, and pairs of sprockets <NUM>, <NUM>, and <NUM>. The sprockets <NUM> are disposed below the sprockets <NUM> and to the other side of the sprockets <NUM> in the width direction.

In this configuration, when a leading-end holding part <NUM> attached to the chains <NUM> reaches the receiving position RE on the upper side of the sprockets <NUM>, the grippers <NUM> of the leading-end holding part <NUM> grip the leading end of a sheet member P that has been transported by the transport rollers <NUM> along the feed path <NUM>, thus receiving and holding the sheet member P.

As shown in <FIG>, the reversing mechanism <NUM> includes the changing rollers <NUM>, transport rollers <NUM>, the switching member <NUM>, and the guide member <NUM>, which transport a sheet member P along a reversing path <NUM>.

The reversing path <NUM> includes the branch path 44a, the changing path 44b, and a joining path 544c. The joining path 544c extends from one side toward the other side in the width direction from an end of the changing path 44b, separately from the branch path 44a, and joins the intermediate portion of the feed path <NUM>.

In the image forming apparatus <NUM> shown in <FIG>, the transport rollers <NUM> of the paper feed mechanism <NUM>, which is disposed to the other side of the receiving position RE in the image forming unit <NUM> in the width direction, transport a sheet member P along the feed path <NUM>. More specifically, the multiple transport rollers <NUM> transport a sheet member P from a storage part <NUM>, which is disposed to the other side of the image forming unit <NUM> in the width direction, toward the receiving position RE.

In contrast, in the image forming apparatus <NUM> as shown in <FIG>, the transport rollers <NUM> of the paper feed mechanism <NUM>, which is disposed to one side of the receiving position RE in the image forming unit <NUM> in the width direction, transport a sheet member P along the feed path <NUM>. More specifically, the transport rollers <NUM> transport a sheet member P from a storage part <NUM>, which is disposed to one side of the image forming unit <NUM> in the width direction, toward the receiving position RE in the image forming unit <NUM>.

The image forming unit <NUM>, <NUM> forms a toner image on the surface of a sheet member P received at the receiving position RE and sends out the sheet member P from the send-out position SE to the discharge path <NUM>.

The cooling unit <NUM> and the multiple transport rollers <NUM> of the paper output mechanism <NUM>, which is disposed to one side of the send-out position SE in the width direction, transport the sheet member P along the discharge path <NUM> and discharge the sheet member P onto the output part <NUM>.

When a toner image is to be formed on the back surface of a sheet member P having a toner image formed on the top surface thereof, the switching member <NUM> guides the sheet member P, which is being transported along the discharge path <NUM>, from the intermediate portion of the discharge path <NUM> to the branch path 44a. The changing rollers <NUM> receive the sheet member P guided from the branch path 44a to the changing path 44b while rotating in one direction and then rotate in the other direction to reverse the sheet transport direction. More specifically, when the changing rollers <NUM> rotating in one direction rotate in the other direction, the rotation of the changing rollers <NUM> rotating in one direction temporarily stops, and then the changing rollers <NUM> rotate in the other direction. Hence, the sheet transport direction is reversed after the transportation of the sheet member P is stopped in the changing path 44b.

Furthermore, the guide member <NUM> guides the sheet member P, whose transport direction has been reversed in the changing path 44b, to the joining path 44c, 544c. The transport roller <NUM>, <NUM> receives the sheet member P transported from the changing path 44b to the joining path 44c, 544c, transports the sheet member P along the joining path 44c, 544c, and feeds the sheet member P to the intermediate portion of the feed path <NUM>, <NUM>. By performing the image forming process again, a toner image is formed on the back surface of the sheet member P. Furthermore, the cooling unit <NUM> of the paper output mechanism <NUM> and the multiple transport rollers <NUM> transport the sheet member P along the discharge path <NUM> and discharge the sheet member P onto the output part <NUM>.

The measurement parts <NUM> shown in <FIG> measure the dimensions of the sheet member P that has been stopped in the changing path 44b of the reversing path <NUM>. The controller <NUM> controls the image forming unit <NUM>, <NUM> to adjust the position of a toner image to be transferred to the sheet member P on the basis of the measurement results obtained by the measurement parts <NUM>. More specifically, the controller <NUM> controls the position of a toner image to be transferred to the sheet member P such that the distances between the edges of the toner image and the edges of the sheet member P are the same across all the edges.

As described above, in the image forming apparatus <NUM>, the paper feed mechanism <NUM> is disposed to the other side of the receiving position RE in the image forming unit <NUM> in the width direction. The feed path <NUM>, along which a sheet member P transported to the receiving position RE in the image forming unit <NUM> passes, extends from the other side toward one side in the width direction. In contrast, in the image forming apparatus <NUM>, the paper feed mechanism <NUM> is disposed to one side of the receiving position RE in the image forming unit <NUM> in the width direction. The feed path <NUM>, along which a sheet member P transported to the receiving position RE in the image forming unit <NUM> passes, extends from one side toward the other side in the width direction.

Furthermore, in the image forming apparatuses <NUM> and <NUM>, the paper output mechanism <NUM> is disposed to one side of the send-out position SE in the image forming unit <NUM> in the width direction. The discharge path <NUM>, along which a sheet member P transported to the output part <NUM> passes, extends from the other side toward one side in the width direction. In the image forming apparatus <NUM>, the feed path <NUM> and the discharge path <NUM> are located at a distance from each other in the width direction (see <FIG>). In other words, the feed path <NUM> and the discharge path <NUM> do not overlap each other in the top-bottom direction (vertical direction). In contrast, in the image forming apparatus <NUM>, the discharge path <NUM> and the feed path <NUM> at least partially overlap each other in the top-bottom direction (vertical direction).

Accordingly, in the image forming apparatus <NUM>, the feed path <NUM> and the discharge path <NUM> occupy a smaller area in the width direction (horizontal direction) than in the image forming apparatus <NUM>.

Furthermore, in the image forming apparatus <NUM>, the discharge path <NUM> is disposed above the feed path <NUM> in the top-bottom direction. Hence, compared with a case where the discharge path <NUM> is disposed below the feed path <NUM>, the position of the output part <NUM> is high. This enables a user to pick up, in a standing state, the sheet member P from the output part <NUM>.

Furthermore, in the image forming apparatus <NUM>, the storage parts 50C and 50D are disposed below the discharge path <NUM> in the top-bottom direction. Hence, compared with a case where the storage parts 50C and 50D and the discharge path <NUM> are located at a distance from each other in the width direction, the storage parts 50C and 50D and the discharge path <NUM> occupy a small area in the horizontal direction.

Furthermore, in the image forming apparatus <NUM>, the reversing path <NUM> is disposed between the feed path <NUM> and the discharge path <NUM> in the top-bottom direction. Hence, compared with a case where the reversing path <NUM> and the area between the feed path <NUM> and the discharge path <NUM> are located at a distance from each other in the width direction, the area between the feed path <NUM> and the discharge path <NUM> is efficiently used.

Furthermore, in the image forming apparatus <NUM>, the measurement parts <NUM> measure the dimensions of a sheet member P that has been stopped in the changing path 44b. Hence, the sheet member P does not need to be stopped only for measuring the dimensions thereof.

Furthermore, in the image forming apparatus <NUM>, the feed path <NUM>, the discharge path <NUM>, and the reversing path <NUM> are disposed so as to overlap one another in the vertical direction at a position not overlapping the image forming unit <NUM> in the vertical direction. Hence, compared with a case where the feed path <NUM>, the discharge path <NUM>, the reversing path <NUM>, and the image forming unit <NUM> are disposed so as to overlap one another in the vertical direction, the height of the body of the image forming apparatus <NUM> does not increase.

In the image forming apparatus <NUM>, the feed path <NUM>, the discharge path <NUM>, and the reversing path <NUM> are disposed in the same housing 14b. More specifically, the reversing path <NUM> joins the feed path <NUM> and the discharge path <NUM> in the housing 14b, in which a portion of the feed path <NUM> and a portion of the discharge path <NUM> are disposed. Hence, compared with a case where the reversing path <NUM> is disposed in a housing other than the housing in which the feed path <NUM> or the discharge path <NUM> is accommodated, the adjustment of the reversing path <NUM> at the time of installing the image forming apparatus <NUM> is simple.

In the image forming apparatus <NUM>, the changing path 44b is disposed below the top of the image forming unit <NUM> in the vertical direction. Hence, the height of the body of the image forming apparatus <NUM> does not increase, compared with a case where the changing path 44b is disposed above the top of the image forming unit <NUM> in the vertical direction.

In the image forming apparatus <NUM>, the discharge path <NUM> is disposed at a position shifted from the image forming unit <NUM> in the horizontal direction such that discharge path <NUM> does not overlap the image forming unit <NUM> in the vertical direction. Hence, compared with a case where the feed path <NUM> and the discharge path <NUM> overlap the image forming unit <NUM> in the vertical direction, the height of the body of the image forming apparatus <NUM> does not increase.

Although a specific exemplary embodiment of the present disclosure has been described in detail above, it is obvious to those skilled in the art that the present disclosure is not limited to the above-described exemplary embodiment, and various modifications, changes, improvements are possible within the scope of the present disclosure. For example, although the cooling unit <NUM> is provided in the discharge path <NUM> in the above-described exemplary embodiment, the cooling unit <NUM> does not need to be provided.

In the above-described exemplary embodiment, although the discharge path <NUM> is disposed above the feed path <NUM> in the top-bottom direction, the discharge path <NUM> may be disposed below the feed path <NUM>. However, in that case, the advantage obtained by disposing the discharge path <NUM> above the feed path <NUM> cannot be obtained.

In the above-described exemplary embodiment, the storage parts 50C and 50D are disposed below the discharge path <NUM> in the top-bottom direction, the storage parts 50C and 50D may be located away from the discharge path <NUM> in the width direction. However, in that case, the advantage obtained by providing the storage parts 50C and 50D below the discharge path <NUM> in the top-bottom direction cannot be obtained.

In the above-described exemplary embodiment, the reversing path <NUM> is disposed between the feed path <NUM> and the discharge path <NUM> in the top-bottom direction, the reversing path does not need to be disposed between the feed path and the discharge path. However, in that case, the advantage obtained by disposing the reversing path <NUM> between the feed path <NUM> and the discharge path <NUM> cannot be obtained.

Furthermore, although not specifically described in the above-described exemplary embodiment, two of the transport rollers <NUM> may function as registration rollers for correcting the orientation of a sheet member P transported.

In the above-described exemplary embodiment, although the sheet member P that is being transported is turned back at the second transfer roller <NUM>, the sheet member P that is being transported may be turned back at, for example, the heater <NUM> of the fixing device <NUM>.

Furthermore, although the reversing mechanism <NUM> is provided in the above-described exemplary embodiment, the reversing mechanism <NUM> does not need to be provided. However, in that case, the advantage obtained by providing the reversing mechanism <NUM> cannot be obtained.

In the above-described exemplary embodiment, the reversing path <NUM> is disposed between the feed path <NUM> and the discharge path <NUM> in the top-bottom direction and is disposed in the housing 14b in which a portion of the feed path <NUM> and a portion of the discharge path <NUM> are disposed. However, in the image forming apparatus according to the present disclosure, as long as the reversing path <NUM> is disposed between the feed path <NUM> and the discharge path <NUM> in the top-bottom direction, the reversing path <NUM> may be disposed in a housing different from the housing in which a portion of the feed path <NUM> and a portion of the discharge path <NUM> are disposed. However, in that case, the advantage obtained by disposing the reversing path <NUM>, a portion of the feed path <NUM>, and a portion of the discharge path <NUM> in the same housing cannot be obtained.

In the above-described exemplary embodiment, the apparatus body <NUM> includes three housings 14a, 14b, and 14c. However, the apparatus body according to the present disclosure may include two housings, or more than three housings. Furthermore, the apparatus body <NUM> according to the present disclosure may have a structure in which the components of the image forming apparatus <NUM> are accommodated in a single housing.

Claim 1:
An image forming apparatus (<NUM>) comprising:
an apparatus body (<NUM>);
an image forming unit (<NUM>) that forms a toner image on a recording medium (P);
a first transport part (<NUM>) that transports the recording medium (P) to the image forming unit (<NUM>) along a feed path (<NUM>) extending from one side toward the other side in the horizontal direction, the feed path (<NUM>) being a path along which the recording medium (P) transported by the first transport part (<NUM>) passes, and that includes a portion extending toward the one side beyond the image forming unit (<NUM>);
a second transport part (<NUM>) that transports the recording medium (P) from the image forming unit (<NUM>) to the outside of the apparatus body (<NUM>) along a discharge path (<NUM>) extending from the other side toward one side in the horizontal direction and that includes a portion extending toward the one side beyond the image forming unit (<NUM>), the discharge path (<NUM>) and the feed path (<NUM>) at least partially overlapping each other in the vertical direction;
a third transport part (<NUM>, <NUM>) that transports the recording medium (P) along a reversing path (<NUM>) splitting from the discharge path (<NUM>) at an intermediate portion thereof, extending from the other side toward the one side in the horizontal direction, extending from the one side toward the other side in the horizontal direction, and joining the feed path (<NUM>) at an intermediate portion thereof;
the reversing path (<NUM>) is disposed between the feed path (<NUM>) and the discharge path (<NUM>) in the vertical direction,
the third transport part (<NUM>, <NUM>) transports the recording medium (P) from the other side toward the one side in the horizontal direction, stops the transportation of the recording medium (P), and then transports the recording medium (P) from the one side toward the other side in the horizontal direction, the image forming apparatus (<NUM>) being characterized in further comprising: a
measurement part (<NUM>) configured to measure the dimensions of the recording medium (P) stopped by the third transport part (<NUM>, <NUM>) and a controller (<NUM>) configured to adjust a position of the toner image such that the distance between edges of the toner image and edges of the recording medium (P) are the same across all the edges.