Image forming device

Abstract

To simplify adjustment work between a forming unit, a transport unit and a fixing unit in setting up an image forming apparatus as compared with a configuration in which any one part of the forming unit, the transport unit and the fixing unit is arranged in another housing.SOLUTION: An image forming apparatus 10 comprises: a forming unit 22 that forms an image on a sheet member; a fixing unit 40 for fixation; a circulation unit 50 that carries the sheet member from the forming unit 22 toward the fixing unit 40 by a circulation of a chain stretched over sprockets 52, 53, 54 between the forming unit 22 and the fixing unit 40; a first feed unit that feeds the sheet member toward the forming unit 22; a discharge unit 16 that discharges the fixed sheet member; a branch unit that carries the sheet member fixed with an image on one surface by allowing it to branch from the discharge unit 16, into joining the first feed unit with front and rear ends of the sheet member replaced; a housing 10c that accommodates the forming unit 22, the fixing unit 40 and the circulation unit 50; and a housing that is connected with the housing 10c and accommodates the feed unit, the discharge unit 16 and the branch unit.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] The present invention relates to an image forming apparatus. [Background technology]

[0002] Patent document 1 describes a printed material transport device that includes a first transport mechanism that supports the underside of a printed material with a circulable belt member and is capable of transporting the material horizontally at a first speed; a second transport mechanism that is arranged so that a parallel running section is formed a predetermined distance downstream of the first transport mechanism in the transport direction of the printed material, and that holds the printed material with a claw mechanism and is capable of transporting the material horizontally at a second speed that is slower than the first speed; and a claw opening / closing mechanism that closes the claw mechanism, which is in an open state in the parallel running section, at a predetermined gripping position and opens the claw mechanism at a predetermined release position in the transport section of the second transport mechanism where the parallel running section has ended. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent Publication No. 2012-140242 Summary of the Invention [Problem to be solved by the invention]

[0004] The object of the present invention is to simplify the adjustment work between the forming unit, conveying unit, and fixing unit when installing an image forming apparatus, compared to a configuration in which any part of the forming unit, conveying unit, and fixing unit is located in a housing separate from the remaining parts. [Means for solving the problem]

[0005] The image forming apparatus according to the first aspect includes a forming unit that forms an image on a recording medium, a fixing unit that fixes the image formed on the recording medium, a circulating unit that transports the recording medium from the forming unit to the fixing unit by rotating a circulating member wrapped around multiple rotating bodies between the forming unit and the fixing unit, a supply unit that supplies the recording medium to the forming unit, a discharge unit that discharges the recording medium on which the image has been fixed by the fixing unit, a branching unit that branches off from the discharge unit to transport the recording medium on which the image has been fixed all over by the fixing unit, swaps the leading and trailing ends of the recording medium, and merges with the supply unit, a first housing that houses the forming unit, the fixing unit, and the circulating unit, and a second housing connected to the first housing that houses the supply unit, the discharge unit, and the branching unit.

[0006] The image forming apparatus of the second aspect is the image forming apparatus of the first aspect, further comprising: a first transport unit housed in the first housing and transporting the recording medium supplied from the supply unit toward the forming unit; a second transport unit housed in the first housing and transporting the recording medium on which an image has been fixed in the fixing unit from the fixing unit toward the discharge unit; and a connecting unit connecting the first housing and the second housing, the connecting unit being positioned closer to the connection unit between the supply unit and the first transport unit than to the connection unit between the second transport unit and the discharge unit.

[0007] An image forming apparatus according to a third aspect is the image forming apparatus according to the second aspect, wherein the supply unit and the first transport unit transport the recording medium in a horizontal direction at a connection between the supply unit and the first transport unit, and are arranged below the first housing and the second housing, and the connecting unit is arranged below the first housing and the second housing.

[0008] An image forming apparatus according to a fourth aspect is the image forming apparatus according to the third aspect, wherein the connecting portion overlaps in the vertical direction with a connecting portion between the supply portion and the first transport portion.

[0009] An image forming apparatus according to a fifth aspect is the image forming apparatus according to the fourth aspect, wherein the first housing and the second housing are aligned horizontally, and the connecting portion includes a positioning portion that positions the first housing and the second housing in a cross direction that crosses the alignment direction of the first housing and the second housing in the horizontal direction, and a fixing portion that fixes the first housing and the second housing to each other at a position that is vertically spaced apart from the positioning portion, and the connection portion between the supply portion and the first conveying portion is arranged vertically between the positioning portion and the fixing portion.

[0010] An image forming apparatus according to a sixth aspect is an image forming apparatus according to any one of the second to fifth aspects, wherein the first housing and the second housing are aligned horizontally, and the connecting portion is provided on each of the side walls on both sides in a cross direction that crosses the alignment direction of the first housing and the second housing in the horizontal direction.

[0011] An image forming apparatus according to a seventh aspect is the image forming apparatus according to the sixth aspect, wherein the connecting portion includes a positioning portion that positions the first housing and the second housing in the intersecting direction using a protruding portion that protrudes in the alignment direction and an inserted portion into which the protruding portion is inserted, and the inserted portion is open at the top.

[0012] An image forming apparatus according to an eighth aspect is the image forming apparatus according to the seventh aspect, wherein the positioning portion is provided on only one of the pair of connecting portions.

[0013] An image forming apparatus according to a ninth aspect is an image forming apparatus according to any one of the first to eighth aspects, further comprising a position adjustment unit that is housed in the first housing and adjusts the position of a recording medium transported toward the forming unit.

[0014] The image forming apparatus of the 10th aspect is the image forming apparatus of the 9th aspect, further comprising a first conveying unit housed below the first housing and conveying the recording medium supplied from the supply unit horizontally toward the forming unit, the circulating unit being positioned above the first conveying unit and forming a space between it and the first conveying unit in the vertical direction, and the position adjustment unit being positioned within the space.

[0015] An image forming apparatus according to an eleventh aspect is an image forming apparatus according to any one of the first to tenth aspects, wherein the branching section is disposed above the supplying section, and the discharging section is disposed above the branching section.

[0016] An image forming apparatus according to a twelfth aspect is an image forming apparatus according to any one of the first to eleventh aspects, further comprising another supply unit housed in the second housing, positioned below the branching unit, transporting a recording medium supplied from outside the second housing and merging with the supply unit.

[0017] An image forming apparatus according to a thirteenth aspect is the image forming apparatus according to any one of the first to twelfth aspects, further comprising a measuring section that measures the dimensions of the recording medium transported to the branching section.

[0018] An image forming apparatus according to a fourteenth aspect is an image forming apparatus according to any one of the first to thirteenth aspects, further comprising another measuring unit housed in the first housing and configured to measure dimensions of a recording medium transported from the supply unit toward the forming unit. [Effects of the Invention]

[0019] Compared to a configuration in which any part of the forming unit, circulating unit, or fixing unit is housed in a housing separate from the remaining parts, this simplifies the adjustment work between the forming unit, circulating unit, and fixing unit when installing the image forming device.

[0020] According to the image forming device of the second aspect, it is possible to suppress poor transport of the recording medium between the supply section and the first conveying section, compared to a configuration in which the connecting section is positioned closer to the connection section between the second conveying section and the discharge section than to the connection section between the first conveying section and the supplying section.

[0021] According to the image forming device of the third aspect, in a configuration in which the supply unit and the first conveying unit are arranged on the lower side of the first housing and the second housing, respectively, poor conveyance of the recording medium between the supply unit and the first conveying unit can be suppressed compared to a configuration in which the connecting unit is arranged only on the upper side of the first housing and the second housing.

[0022] According to the image forming device of the fourth aspect, it is possible to suppress poor transport of the recording medium between the supply unit and the first transport unit, compared to a configuration in which the vertical position of the connecting part is shifted from the connection part between the supply unit and the first transport unit.

[0023] According to the image forming device of the fifth aspect, compared to a configuration in which the connection portion between the first conveying portion and the supplying portion is shifted in the vertical direction from between the positioning portion and the fixing portion, it is possible to suppress poor conveyance of the recording medium between the supplying portion and the first conveying portion.

[0024] According to the image forming device of the sixth aspect, compared to a configuration in which the first housing and the second housing are connected by a connecting portion provided on only one side wall in the intersecting direction, it is possible to suppress poor transport of the recording medium between the supply portion and the first transport portion.

[0025] According to the image forming apparatus of the seventh aspect, the state of the protruding portion inserted into the inserted portion can be easily visually confirmed from above, compared to a configuration in which the top of the inserted portion is closed.

[0026] According to the image forming apparatus of the eighth aspect, the workability of connecting the first housing and the second housing is improved compared to a configuration in which a positioning portion using a protruding portion and an inserted portion is provided on both of a pair of connecting portions.

[0027] According to the image forming apparatus of the ninth aspect, compared to a configuration in which the position adjustment unit is housed in the second housing, it is possible to suppress transport failure of the recording medium being transported to the formation unit.

[0028] According to the image forming apparatus of the tenth aspect, the horizontal position of the position adjustment unit housed in the first housing can be prevented from increasing the horizontal length of the first housing compared to a configuration in which the position adjustment unit is located closer to the supply unit than the circulating unit.

[0029] According to the image forming apparatus of the eleventh aspect, the operator can receive the recording medium discharged from the discharge section while standing.

[0030] According to the image forming apparatus of the twelfth aspect, it is possible to prevent the vertical length of the second housing from increasing, compared to a configuration in which the other supply unit is disposed above the branch unit.

[0031] According to the image forming device of the 13th aspect, compared to a configuration in which only the dimensions of the recording medium transported from the supply section to the forming section are measured, it is possible to suppress variation in the dimensional ratio of the image formed on the back side of the recording medium to the image formed on the front side of the recording medium during double-sided printing.

[0032] According to the image forming apparatus of the fourteenth aspect, the positional accuracy of the image formed on the recording medium relative to the recording medium is improved compared to a configuration in which only the dimensions of the recording medium transported to the branching section are measured. [Brief explanation of the drawings]

[0033] [Figure 1] 1 is a front cross-sectional view showing a configuration of an image forming apparatus according to an embodiment. [Figure 2] FIG. 2 is a front cross-sectional view showing the housing of the image forming apparatus according to the embodiment. [Figure 3] FIG. 2 is a front cross-sectional view showing the housing of the image forming apparatus according to the embodiment. [Figure 4] 1 is a front view showing an image forming apparatus according to an embodiment; [Figure 5] FIG. 1 is a plan view showing an image forming apparatus according to an embodiment. [Figure 6] FIG. 2 is a perspective view showing a connecting portion according to the embodiment. [Figure 7] FIG. 2 is a perspective view showing a connecting portion according to the embodiment. [Figure 8] FIG. 2 is a perspective view showing a connecting portion according to the embodiment. [Figure 9] FIG. 2 is a perspective view showing a connecting portion according to the embodiment. [Figure 10] FIG. 2 is a perspective view showing a connecting portion according to the embodiment. [Figure 11] FIG. 2 is a perspective view showing a connecting portion according to the embodiment. [Figure 12] FIG. 2 is a plan view showing a measuring unit according to the embodiment. [Figure 13] FIG. 2 is a front view showing a position adjustment unit according to the embodiment. [Figure 14] FIG. 1 is a perspective view showing a chain gripper according to an embodiment. [Figure 15] 1 is a perspective view showing a configuration around an image forming position of an image forming apparatus according to an embodiment; [Figure 16] FIG. 2 is a perspective view showing a fixing unit according to the embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0034] An image forming apparatus 10 according to an embodiment of the present invention will be described with reference to FIGS.

[0035] In the following description, the device up-down direction (height direction), device width direction (horizontal direction), and device depth direction (horizontal direction) are respectively referred to as the H direction, W direction, and D direction when viewing the image forming device 10 from the front from the side where a user (not shown) stands. Furthermore, when it is necessary to distinguish one side from the other in the device up-down direction, device width direction, and device depth direction, when viewing the image forming device 10 from the front, the upper side will be referred to as the +H side, the lower side as the -H side, the right side as the +W side, the left side as the -W side, the back side as the -D side, and the front side as the +D side.

[0036] <Image forming apparatus 10> The image forming apparatus 10 according to this embodiment is an electrophotographic image forming apparatus that forms a toner image on a sheet member P as a recording medium. As shown in Fig. 1, the image forming apparatus 10 includes a storage section 12, a first supply section 14, a second supply section 15, an image forming section 20, a discharge section 16, a branch section 17, a discharged section 18, and a control section 19 that controls each section. The image forming apparatus 10 further includes a main body that houses the various components. The main body is composed of three generally rectangular housings that are connected and aligned in the width direction of the apparatus. The three housings are named housing 10a, housing 10b, and housing 10c, respectively, from the -W side. Housing 10c houses the image forming unit 20. Housing 10b houses a first supply unit 14, a second supply unit 15, a discharge unit 16, and a branch unit 17. Details of housings 10a, 10b, and 10c will be described later. As shown in FIG. 4, the image forming apparatus 10 further includes a first connecting unit 70 that connects housings 10a and 10b together, and a second connecting unit 80 that connects housings 10b and 10c together. In addition, the image forming apparatus 10 further includes a measuring unit 96 that measures the dimensions of the sheet material P being transported toward the forming unit 22 (details of which will be described later) of the image forming unit 20, and a position adjustment unit 90 that adjusts the position of the sheet material P.

[0037] (Storage section) The storage units 12 have a function of storing sheet materials P. The image forming apparatus 10 is provided with four storage units 12. The sheet materials P are selectively sent out from the four storage units 12. In this embodiment, two storage units 12 are arranged in the vertical direction of the device inside the housing 10a, and two other storage units 12 are arranged in the width direction of the device inside the housing 10b.

[0038] (1st supply section) The first supply unit 14 has a function of transporting the sheet material P stored in the storage unit 12 of the housing 10b using a plurality of transport rolls (not shown) arranged in the housing 10b, and supplying the sheet material P to the image forming unit 20 of the housing 10c. The first supply unit 14 is an example of a supply unit.

[0039] (2nd supply section) The second supply section 15 has a function of conveying the sheet material P stored in the storage section 12 of the housing 10a using a plurality of conveying rolls (not shown) arranged in the housings 10a and 10b, and then joining the first supply section 14 to supply the sheet material P toward the image forming section 20 in the housing 10c. The second supply section 15 is an example of another supply section. As shown in FIG. 3, the second supply section 15 joins the first supply section 14 so as to pass between a branch section 17 (described later) and the storage section 12 in the vertical direction of the device. That is, the second supply section 15 is arranged below the branch section 17.

[0040] (Image forming section) The image forming unit 20 is disposed within the housing 10c and has a function of forming an image on a sheet material P by electrophotography. The image forming unit 20 includes a forming unit 22 that forms a toner image on the sheet material P, a fixing unit 40 that fixes the toner image formed on the sheet material P to the sheet material P, and a chain gripper 50 that transports the sheet material P from the forming unit 22 toward the fixing unit 40. The image forming unit 20 also includes a first transport unit 20a that transports the sheet material P supplied from the supply unit 14 to the housing 10c in a direction along the device width direction (horizontal direction) toward a receiving position D1 (described in detail later) of the chain gripper 50. The image forming unit 20 also includes a second transport unit 20b that transports the sheet material P, on which the toner image has been fixed by the fixing unit 40, in a direction along the device width direction (horizontal direction) toward an output unit 16 of the housing 10b.

[0041] The first conveying section 20a and the second conveying section 20b each include a plurality of conveying rolls (not shown). The first conveying section 20a is connected to the first supplying section 14. The second conveying section 20b is connected to the discharging section 16. The connection between the first conveying section 20a and the first supplying section 14 and the connection between the second conveying section 20b and the discharging section 16 are connection sections 11 and 13, respectively.

[0042] The first transport unit 20a is disposed below the housing 10c. Specifically, the first transport unit 20a is disposed on the -H side of the center line between the upper and lower surfaces of the housing 10c. More specifically, the first transport unit 20a is disposed on the +H side of the lower surface of the housing 10c, within a range of one-third of the length between the upper and lower surfaces of the housing 10c.

[0043] The second transport unit 20b is disposed above the housing 10c. Specifically, the second transport unit 20b is disposed on the +H side of the center line between the top and bottom surfaces of the housing 10c. More specifically, the first transport unit 20a is disposed on the -H side from the top surface of the housing 10c, within a range of one-third of the length between the top and bottom surfaces of the housing 10c.

[0044] The forming section 22 includes a photosensitive unit 23 that forms a toner image, and a transfer device 30 that transfers the toner image formed by the photosensitive unit 23 onto a sheet member P.

[0045] A plurality of photosensitive units 23 are provided so as to form toner images for each color. In this embodiment, photosensitive units 23 for a total of four colors, yellow (Y), magenta (M), cyan (C), and black (K), are provided. Y, M, C, and K shown in FIG. 1 indicate components corresponding to the above-mentioned colors. When there is no particular distinction between the colors (Y, M, C, and K), the last alphabet will be omitted.

[0046] [Photoconductor unit] The photosensitive units 23Y, M, C, and K (23Y, 23M, 23Y, and 23K) are basically configured in the same manner except for the toner used.

[0047] As shown in FIG. 1, the photosensitive units 23Y, 23M, 23C, and 23K are arranged along the inclined portion of a transfer belt 31 (details of which will be described later) of a transfer device 30.

[0048] 2, the photosensitive unit 23 includes a photosensitive drum 24 that rotates in the direction of arrow A02 in the figure, and a charger 26 that charges the photosensitive drum 24. The photosensitive unit 23 also includes an exposure device 28 that exposes the photosensitive drum 21 charged by the charger 26 to light to form an electrostatic latent image, and a development device 29 that develops the electrostatic latent image with toner to form a toner image.

[0049] [Transfer device] The transfer device 30 has a function of primarily transferring the toner images of the photosensitive drums 24 of each color onto an intermediate transfer body in a superimposed manner, and then secondarily transferring the superimposed toner images onto a sheet member P. Specifically, as shown in FIG. 2 , the transfer device 30 includes a transfer belt 31 as an intermediate transfer body, a plurality of rolls 32, a primary transfer roll 34, a secondary transfer roll 33, and a transfer body 36.

[0050] The transfer belt 31 is endless and is wound around multiple rolls 32 so as to assume a generally inverted triangular position. Of the multiple rolls 32 that position the transfer belt 31, the roll 32 on the -W side and the roll 32 on the -H side are roll 32a and roll 32b, respectively. The transfer belt 31 rotates in the direction of arrow X when at least one of the multiple rolls 32 is driven to rotate.

[0051] The primary transfer roll 34 is a roll-shaped member that is disposed on the opposite side of the photosensitive drum 24 of each color across the transfer belt 31. The primary transfer roll 34 has a function of transferring the toner image formed on the photosensitive drum 24 to the transfer belt 31 at a primary transfer position T between the photosensitive drum 24 and the primary transfer roll 34.

[0052] The secondary transfer roll 33 is a roll-shaped member that is disposed between the -W-side roll 32 and the -H-side roll 32, among the rolls 32 around which the transfer belt 31 is wound in a substantially inverted triangular shape, on the inside of the transfer belt 31, so as to be in contact with the transfer belt 31. The transfer body 36 is a roll-shaped member that extends in the depth direction of the device and is disposed on the opposite side of the transfer belt 31 from the secondary transfer roll 33. The secondary transfer roll 33 and the transfer body 36 have the function of transferring the toner image transferred to the transfer belt 31 to the sheet material P at a secondary transfer position NT between the transfer belt 31 and the transfer body 36.

[0053] [Chain gripper] The chain gripper 50 includes a pair of chains 51, a tip holding portion 55 that holds the tip of the sheet material P, and sprockets 52, 53, and 54. The chain 51 is an example of a rotating member. The sprockets 52, 53, and 54 are an example of a rotating body. The chain gripper 50 is an example of a rotating portion.

[0054] As shown in Fig. 14, the pair of chains 51 are spaced apart in the depth direction of the device, and the chains 51 are endless. As shown in Fig. 15, the pair of chains 51 are arranged on both ends of the transfer body 36 in the longitudinal direction (axial direction) and are wound around a pair of sprockets 52 whose axial direction is the longitudinal direction. Furthermore, the pair of chains 51 are arranged on both sides of the pressure roll 42 (described below) in the longitudinal direction (axial direction) and are wound around a pair of sprockets 53 (see Fig. 16) whose axial direction is the longitudinal direction. Furthermore, as shown in Fig. 2, the pair of chains 51 are wound around a pair of sprockets 54 which are spaced apart in the depth direction of the device.

[0055] The sprockets 53 arranged on both sides of the pressure roll 42 in the longitudinal direction are arranged on the −W side and +H side with respect to the sprockets 52 arranged on both sides of the transfer body 36 in the longitudinal direction.

[0056] Furthermore, when viewed from the depth direction of the device, the pair of sprockets 54 are disposed below the sprockets 52 and 53, on the -W side of the sprocket 52, and on the +W side of the sprocket 53. Furthermore, a transport roll (not shown) is disposed between the pair of sprockets 54 and is coaxial with the pair of sprockets 54.

[0057] As shown in Figure 14, the tip holding portion 55 has an attachment member 56 extending in the depth direction of the device and a gripper 57 attached to the attachment member 56, and both sides of the tip holding portion 55 in the depth direction of the device are respectively attached to a pair of chains 51.

[0058] A plurality of tip holders 55 are provided and are arranged at predetermined intervals along the circumferential direction (circumferential direction) of the chain 51.

[0059] A plurality of grippers 57 are provided and attached to the attachment member 56 at predetermined intervals along the depth direction of the device. The grippers 57 have the function of holding the leading edge of the sheet material P. Specifically, the grippers 57 have claws 57a. The attachment member 56 is also formed with contact portions 56a with which the claws 57a come into contact.

[0060] Gripper 57 is configured to hold sheet material P by pinching the leading end of sheet material P between claw 57a and contact portion 56a. Note that gripper 57 has claw 57a pressed against contact portion 56a by a spring or the like, and claw 57a is moved toward and away from contact portion 56a by the action of a cam or the like, for example.

[0061] In this configuration, when a rotational force is transmitted to one of the multiple sprockets 52, 53, and 54 shown in Figure 2, the pair of chains 51 rotates in the direction of arrow C in the figure, moving from the sprocket 52 side to the sprocket 53 side.

[0062] Furthermore, when the leading edge holding portions 55 attached to the pair of chains 51 reach the receiving position D1 at the lower end of the sprocket 54, the grippers 57 of the leading edge holding portions 55 pinch the leading edge of the sheet material P conveyed along the first supply unit 14 and the first conveying unit 20a to hold and receive the sheet material P. Then, the chains 51, which rotate in the direction of arrow C, transport the sheet material P held by the leading edge holding portions 55 to the secondary transfer position NT, thereby transferring the toner image onto the sheet material P. The rotating chains 51 then transport the sheet material P from the secondary transfer position NT to the fixing unit 40, thereby fixing the toner image onto the sheet material P. At the sending position D2, where the leading edge of the sheet material P has passed the fixing unit 40, the leading edge holding portions 55 release their hold on the leading edge of the sheet material P, and the chain grippers 50 send the sheet material P to the second conveying unit 20b and the discharging unit 16.

[0063] The chain gripper 50 is configured such that the path of its circulation is inclined downward from the time it passes through the fixing unit 40 (sending position D2) until it passes through the junction with the first conveying unit 20a (receiving position D1). This path that slopes downward from the sending position D2 toward the receiving position D1 is the inclined portion DT. With this configuration, the inclined portion DT forms a space S sandwiched between the inclined portion DT and the first conveying unit 20a. In this embodiment, the space S has a vertical height that decreases horizontally from the sending position D2 toward the receiving position D1. In other words, the space S has a vertical height that decreases horizontally from the fixing unit 40 toward the secondary transfer position NT.

[0064] [Fixing section] As shown in FIG. 2, the fixing unit 40 is disposed downstream of the transfer body 36 in the sheet conveying direction.

[0065] As shown in Figure 16, the fixing section 40 includes a heating roll 44 that contacts the transported sheet material P and heats the sheet material P, a pressure roll 42 that presses the sheet material P toward the heating roll 44, and a driven roll 46 that rotates in response to the heating roll 44.

[0066] The heating roll 44 is a roll-shaped member that contacts the upward surface of the sheet material P being conveyed and is arranged so as to extend in the device depth direction with its axial direction being the device depth direction. Furthermore, shaft portions 44a extending in the device depth direction are formed on both ends of the heating roll 44 in the device depth direction, and support members 44b that support the shaft portions 44a are provided.

[0067] The driven roll 46 is a roll-shaped member that is disposed on the opposite side of the sheet member P being conveyed across the heating roll 44, with its axial direction extending in the device depth direction. The driven roll 46 also has a heater (not shown). In this configuration, the driven roll 46 rotates in response to the rotation of the heating roll 44. The driven roll 46 heats the heating roll 44.

[0068] The pressure roll 42 is a roll-shaped member that is disposed on the opposite side of the heating roll 44 with the sheet material P being conveyed therebetween, in contact with the downward-facing surface of the sheet material P being conveyed, and extends in the device depth direction with its axial direction being the device depth direction. The pressure roll 42 has shaft portions 42a that extend along the axial direction at both ends in the device depth direction.

[0069] Furthermore, the fixing unit 40 includes a support member 48 that supports the shaft portion 42a of the pressure roll 42, and a biasing member 49 that biases the pressure roll 42 toward the heating roll 44 via the support member 48. The support member 48 is disposed so as to rotatably support the shaft portion 42a of the pressure roll 42 from below.

[0070] In this configuration, the urging member 49 urges the pressure roll 42 toward the heating roll 44, causing the pressure roll 42 to press the sheet member P toward the heating roll 44. Furthermore, a rotational force is transmitted to the pressure roll 42 from a driving member (not shown), causing it to rotate. The heating roll 44 then rotates in response to the rotating pressure roll 42, and the driven roll 46 then rotates in response to the rotating heating roll 44. Furthermore, the heating roll 44 and the pressure roll 42 sandwich and transport the sheet member P to which the toner image has been transferred, causing the toner image to be heated and fixed to the sheet member P.

[0071] (Discharge section) The discharge section 16 is provided in the housing 10b and has the function of discharging the sheet material P, which has had a toner image fixed by the fixing section 40 in the housing 10c and is transported from the second transport section 20b toward the housing 10b, from a discharge opening provided on the side of the housing 10b facing the housing 10a. In this embodiment, the sheet material P discharged from the discharge port of the housing 10b is delivered to an extended discharge portion 16a provided in the housing 10a, and is discharged to a discharged portion 18 provided outside the housing 10a.

[0072] (branch) The branching section 17 is provided by branching off from the discharge section 16 of the housing 10b, and has a function of switching the leading end and trailing end of the sheet material P transported to the branching section 17 and causing the sheet material P to merge with the first supply section 14. Specifically, the branching section 17 has a function of changing the transport direction of the sheet material P transported from the discharge section 16 to the branching section 17, to a direction opposite to the transport direction of the discharge section 16 downstream of the fixing section 40.

[0073] Branching portion 17 is disposed above storage portion 12 in housing 10b. Branching portion 17 is also disposed below discharge portion 16 in housing 10b.

[0074] The branching section 17 is equipped with a measuring section 17a that measures the dimensions of the sheet material P transported to the branching section 17. As shown in FIG. 12, the measuring section 17a is configured to include a plurality of measurement sensors 17b. The measuring section 17a measures the dimensions of the sheet material P that has had a toner image fixed by the fixing section 40 and is transported to the branching section 17, as well as the dimensions of the image fixed on the sheet material P, and transmits the measurement results to the control section 19.

[0075] The sheet material P that has been transported to the branching unit 17 and merged with the first supply unit 14 has its leading and trailing ends swapped, and is therefore transported to the secondary transfer position NT in a state where the front and back of the sheet material P are inverted from before being transported to the branching unit 17. That is, the sheet material P that has been transported to the branching unit 17, merged with the first supply unit 14, and transported to the secondary transfer position NT has a toner image transferred onto a surface (back surface) different from the surface (front surface) on which the toner image was formed before being transported to the branching unit 17. At this time, the control unit 19 applies a correction to the size of the toner image formed on the back surface of the sheet material P in accordance with the measured dimensions of the sheet material P and the dimensions of the toner image formed on the front surface, based on the measurement result of the measurement unit 17a of the branching unit 17.

[0076] (Position adjustment part) 2, the position adjustment unit 90 is housed in the housing 10c, with a portion of its upper side disposed within the space S, and has the function of adjusting the position of the sheet material P being transported to the receiving position D1. As shown in FIG. 13, the position adjustment unit 90 is configured to include a plurality of rolls 91, a plurality of sensors 92, and a stopper 93.

[0077] The rolls 91 are arranged in pairs above and below the first conveyor 20a along the first conveyor 20a. Specifically, the position adjustment unit 90 includes roll pairs 91a, 91b, and 91c arranged in order from the -W side along the first conveyor 20a.

[0078] The stopper 93 is a member provided on the roll pair 91b and formed in a substantially N-shape when viewed from the +D side. The downstream end of this stopper 93 in the paper conveyance direction is a gate portion 93a that is raised so as to intersect with the first conveyance section 20a. When the leading edge of the sheet material P is supplied to the position adjustment section 90, it abuts against the gate portion 93a, thereby adjusting the timing of paper conveyance, misalignment in the paper width direction, or inclination of the paper. In other words, the position adjustment section 90 adjusts the position of the sheet material P conveyed to the receiving position D1 by the gate portion 93a provided on the roll pair 91b.

[0079] An elevator (not shown) including a gear, a motor, etc. is provided upstream of the stopper 93 in the paper transport direction. The stopper 93 is configured so that the gate portion 93a of the stopper 93 can be moved up and down by the elevator.

[0080] When the gate portion 93a is moved upward, the gate portion 93a is moved to a position where it blocks the first conveying portion 20a. In this case, the sheet material P being conveyed through the first conveying portion 20a is stopped from being conveyed at the position of the gate portion 93a. On the other hand, when the gate portion 93a is moved downward, the gate portion 93a is moved to a position where it does not block the first conveying portion 20a. In this case, the sheet material P being conveyed is conveyed through the first conveying portion 20a without being interfered with by the gate portion 93a.

[0081] The plurality of sensors 92 detects whether the sheet material P being conveyed through the first conveying unit 20a is passing or not. The control unit 19 receives signals from the sensors 92 and controls the operation of the rolls 91 of the position adjusting unit 90 as appropriate.

[0082] (Measurement part) The measurement unit 96 is disposed along the first conveying unit 20a, upstream of the position adjustment unit 90 in the conveying direction, and is configured to include a plurality of sensors (not shown). The measurement unit 96 measures the dimensions of the sheet material P conveyed through the first conveying unit 20a, and transmits the measurement results to the control unit 19. Based on the measurement results of the measurement unit 96, the control unit 19 applies a correction to the relative position of the toner image formed on the sheet material P with respect to the sheet material P in accordance with the measured dimensions of the sheet material P. The measurement unit 96 is an example of another measurement unit.

[0083] (Housing) Each of the housings 10a, 10b, and 10c has a rectangular parallelepiped frame and walls covering each side of the frame. Of the walls of the housings 10a, 10b, and 10c, the walls facing the width and depth directions of the device are referred to as side walls. Furthermore, of the walls of the housings 10a, 10b, and 10c, the wall covering the -H side surface is referred to as a bottom wall.

[0084] The side wall facing the -W side of the housing 10c has corresponding openings formed so that the first conveying section 20a and the second conveying section 20b can be connected to the first supply section 14 and the discharge section 16 of the housing 10b at the connection section 11 and the connection section 13, respectively.

[0085] The side wall of housing 10b facing the +W side has openings formed therein so that first supply unit 14 and discharge unit 16 can be connected to first transport unit 20a and second transport unit 20b of housing 10c at connection unit 11 and connection unit 13, respectively. Also, the side wall of housing 10b facing the -W side has openings formed therein so that discharge unit 16 and second supply unit 15 can be connected to extended discharge unit 16a and second supply unit 15 of housing 10a, respectively. Housing 10b is an example of a second housing.

[0086] Openings are formed in the side wall of the housing 10a facing the +W side so that the extended discharge portion 16a and the second supply portion 15 can be connected to the discharge portion 16 and the second supply portion 15 of the housing 10b, respectively.

[0087] The housings 10a, 10b, and 10c each have a bottom frame with multiple legs (not shown) that can adjust the height of the device in the vertical direction. The housings 10a, 10b, and 10c have a function that allows the position of the device in the vertical direction to be adjusted by adjusting the legs in the vertical direction.

[0088] (First connecting portion and second connecting portion) The first connecting portion 70 and the second connecting portion 80 are basically configured in the same way except for the objects to be connected. In describing the first connecting portion 70 and the second connecting portion 80, the structure of the second connecting portion 80 will be described as a representative.

[0089] As shown in Fig. 5, the second connecting portion 80 is provided on the side walls on both sides in the depth direction of the device at the boundary between the housings 10b and 10c, and is a member that connects the housings 10b and 10c. As shown in Fig. 4, the second connecting portion 80 is disposed on the -H side of the center line of the housings 10b and 10c in the up-down direction of the device. That is, the second connecting portion 80 is disposed below the housings 10b and 10c. In other words, the second connecting portion 80 is disposed at a position closer to the connecting portion 11 between the supply portion 14 and the first transport portion 20a than to the connecting portion 13 between the second transport portion 20b and the discharge portion 16.

[0090] 5, the second connecting portion 80 includes a block pair 81 provided on the +D sidewall of the housing 10b and the housing 10c, and a block pair 86 provided on the -D sidewall of the housing 10b and the housing 10c. That is, the block pair 81 and the block pair 86 are arranged as a pair. The block pair 81 and the block pair 86 are each an example of a connecting portion.

[0091] As shown in FIG. 6, the block pair 81 includes a block 82 provided in the housing 10b, a block 83 provided in the housing 10c, and a bolt 84 that fastens the blocks 82 and 83 together.

[0092] As shown in FIG. 7, the block 83 has a rectangular main body 83a and a generally cylindrical positioning pin 83b that protrudes toward the -W side from the upper side of the end surface of the main body 83a facing the -W side. The positioning pin 83b is an example of a protrusion. The block 83 also has a screw hole 83c that penetrates the main body 83a in the device width direction at a position on the -H side of the positioning pin 83b and corresponds to the bolt 84. The main body 83a is disposed so as to straddle the first supply unit 14 of the housing 10b in the vertical direction of the device. That is, the main body 83a is positioned above the first supply unit 14 in the vertical direction of the device. As shown in FIG. 4, the positioning pin 83b is formed on the +H side of the first transport unit 20a of the housing 10c. The screw hole 83c is formed on the -H side of the first transport unit 20a of the housing 10c. The positioning pin 83b has a tapered surface formed by chamfering the edge of the tip.

[0093] As shown in FIG. 8 , the block 82 has a rectangular main body 82a and a recess 82b, where a portion of the upper side of the end surface of the main body 82a facing the +W side is recessed relative to the end surface. The block 82 also has a through-hole 82c that penetrates the main body 82a in the device width direction at a position corresponding to the screw hole 83c of the block 83 and corresponds to the bolt 84. The main body 82a is disposed so as to straddle the first transport unit 20a of the housing 10c in the device vertical direction. That is, the main body 82a is positioned so as to overlap the first transport unit 20a in the device vertical direction. The recess 82b has a size that allows the positioning pin 83b of the block 83 to be inserted therein. The recess 82b is an example of an insertion portion. The width of the recess 82b in the device depth direction is dimensioned to provide a clearance fit with the width of the positioning pin 83b of the block 83 in the device depth direction. The recess 82b is open at the top and is formed as a groove extending from the end surface facing the +H side of the block 82 toward the -H side. The recess 82b is formed on the +H side of the first supply unit 14 of the housing 10b. The through-hole 82c is formed on the -H side of the first supply unit 14 of the housing 10b. The recess 82b has a tapered surface formed by chamfering the edge on the +W side. The tapered surface of the recess 82b has a function of guiding the positioning pin 83b of the housing 10c, which is inserted into the recess 82b, into the recess 82b.

[0094] The block pair 86 has a configuration symmetrical to the block pair 81 in the device depth direction, except that the block pair 86 does not have the positioning pin 83b and recessed portion 82b of the block pair 81. In other words, the positioning pin 83b and recessed portion 82b of the second connecting portion 80 are provided only on the block pair 81 on the +D side. 9, block pair 86 is configured to include blocks 87, 88, and bolt 89 instead of blocks 82, 83, and bolt 84 in block pair 81. The position of block pair 86 in the vertical direction of the device is the same as the position of block pair 81 in the vertical direction of the device. In other words, the position of block pair 86 in the vertical direction of the device overlaps with first transport section 20a (connection section 11). 10, the block 88 has a screw hole 88c in place of the screw hole 83c of the block 83. The end surface of the block 88 facing the -W side is flat except for the screw hole 88c. 11, the block 87 has a through hole 87c in place of the through hole 82c of the block 82. The end face of the block 87 facing the +W side is flat except for the through hole 87c.

[0095] When the surfaces of blocks 82 and 83 facing each other and the surfaces of blocks 87 and 88 facing each other come into contact in the device width direction, the side wall of housing 10b facing the +W side and the side wall of housing 10c facing the -W side are configured to face each other at a predetermined distance. In other words, when the surfaces of blocks 82 and 83 facing each other and the surfaces of blocks 87 and 88 facing each other come into contact in the device width direction, housings 10b and 10c are positioned in the device width direction. In other words, when the surfaces of blocks 82 and 83 facing each other and the surfaces of blocks 87 and 88 facing each other come into contact in the device width direction, the first supply unit 14 and the first transport unit 20a are positioned in the device width direction.

[0096] Furthermore, when the end faces of blocks 82 and 83 facing the +H side and the end faces of blocks 87 and 88 facing the +H side are flush with each other, the first supply unit 14 and the first transport unit 20a are positioned at the same position in the vertical direction of the device. In other words, when the end faces of blocks 82 and 83 facing the +H side and the end faces of blocks 87 and 88 facing the +H side are flush with each other, the first supply unit 14 and the first transport unit 20a are positioned in the vertical direction of the device. Note that flush means that the two surfaces are located within a range of ±0.2 mm in the vertical direction of the device from a predetermined height position in the vertical direction of the device.

[0097] Furthermore, when the positioning pin 83b of the block 83 is entirely inserted into the recess 82b of the block 82, the first supply unit 14 and the first transport unit 20a are positioned in the depth direction of the device at the same position. That is, when the positioning pin 83b of the block 83 is entirely inserted into the recess 82b of the block 82, the first supply unit 14 and the first transport unit 20a are positioned in the depth direction of the device. The combination of the positioning pin 83b and the recess 82b is an example of a positioning unit.

[0098] In this way, first supply unit 14 and first transport unit 20a are connected by being positioned by blocks 82 and 83. Furthermore, housings 10b and 10c are also positioned by blocks 82 and 83. After first supply unit 14 and first transport unit 20a have been positioned, bolt 84 is inserted into through hole 82c and threaded hole 83c to fasten them, and bolt 89 is inserted into through hole 87c and threaded hole 88c to fasten them, thereby fixing housings 10b and 10c to each other. The combination of bolts 84 and 89, through holes 82c and 87c, and threaded holes 83c and 88c is an example of a fixing unit.

[0099] When housings 10b and 10c are fixed in a positioned state, block pair 81, 86 are positioned in the vertical direction of the device so as to overlap connection portion 11 between first supply unit 14 and first transport unit 20a. Furthermore, when housings 10b and 10c are fixed in a positioned state, connection portion 11 between first supply unit 14 and first transport unit 20a is disposed between recess 82b and bolt 84 in the vertical direction of the device.

[0100] 4 and 5, the first connecting portion 70 is provided on the side walls on both sides in the device depth direction at the boundary between the housings 10a and 10b, and has a configuration similar to that of the second connecting portion 80, except that it connects the housings 10a and 10b. The first connecting portion 70 is also located on the -H side of the center line of the housings 10a and 10b in the device up-down direction. In other words, the first connecting portion 70 is located below the housings 10a and 10b.

[0101] (others) When positioning the housings 10a, 10b, and 10c in the up-down direction, the above-mentioned multiple legs (not shown) are extended or retracted to adjust the respective positions in the up-down direction of the device, thereby making the end faces facing the +H side of blocks 82 and 83 flush with each other. This also applies to the end faces facing the +H side of blocks 87 and 88 and the end faces facing the +H side of the pair of blocks of the first connecting portion 70 that face each other.

[0102] (Action and effect) Next, the operation and effects of the embodiment will be described. In this description, when describing a comparative embodiment to the embodiment, if the same parts as those in the image forming apparatus 10 of the embodiment are used, the reference numerals and names of those parts will be used as they are.

[0103] The image forming apparatus 10 of the embodiment has a configuration in which the image forming unit 20 is disposed in a housing 10c. That is, the image forming apparatus 10 of the embodiment has a configuration in which the housing 10c accommodates the forming unit 22, the fixing unit 40, and the chain gripper 50.

[0104] When forming a toner image on a sheet material P, the image forming apparatus 10 first transports the sheet material P stored in the storage unit 12 to a receiving position D1 of the chain gripper 50 using the first supply unit 14 and the first transport unit 20a. Next, the image forming apparatus 10 holds the sheet material P transported to the receiving position D1 using the chain gripper 50 and transports it to the secondary transfer position NT, where the toner image is transferred (formed) on the sheet material P in the forming unit 22. Thereafter, the image forming apparatus 10 transports the sheet material P, to which the toner image has been transferred at the secondary transfer position NT, while still held by the chain gripper 50, to the fixing unit 40, where the toner image is fixed on the sheet material P. Thereafter, the image forming apparatus 10 transports the sheet material P, to which the toner image has been fixed in the fixing unit 40, using the second transport unit 20b and the discharge unit 16. In the case of single-sided printing, the image forming apparatus 10 further transports the sheet material P transported by the second transport unit 20b and the discharge unit 16 using the extended discharge unit 16a and discharges it to the discharged portion 18. In the case of double-sided printing, the image forming device 10 transports the sheet material P transported by the second transport section 20b and the discharge section 16 to the branch section 17 to swap the leading and trailing ends of the sheet material P, and then merges with the first supply section 14 to transport it again to the receiving position D1 and the secondary transfer position NT.

[0105] As described above, when a toner image is formed on the sheet material P by the image forming apparatus 10, the sheet material P is transported to each section of the image forming apparatus 10, and therefore, adjustment work is required to adjust the transport accuracy of the sheet material P when the image forming apparatus 10 is installed. In particular, it is necessary to adjust the transport accuracy of the sheet material P between the chain gripper 50, the forming section 22, and the fixing section 40 so that the toner image formed on the sheet material P does not deviate from the user's settings. Furthermore, since the image forming apparatus 10 is made up of multiple housings, it is necessary to adjust the transport accuracy of the sheet material P between the different housings when the image forming apparatus 10 is installed.

[0106] The image forming apparatus 10 of the embodiment has a configuration in which the forming unit 22, the fixing unit 40, and the chain gripper 50 are housed in a single housing 10c. Therefore, when the image forming apparatus 10 is installed, it is not necessary to adjust the conveyance accuracy of the sheet material P between the forming unit 22, the fixing unit 40, and the chain gripper 50 between different housings. Therefore, the image forming apparatus 10 of the embodiment can simplify the adjustment work between the forming unit 22, the chain gripper 50, and the fixing unit 40 compared to a configuration in which any part of the forming unit 22, the chain gripper 50, and the fixing unit 40 is housed in a housing separate from the remaining parts. In other words, the image forming apparatus 10 of the embodiment can simplify the adjustment work between the forming unit 22, the chain gripper 50, and the fixing unit 40 when the image forming apparatus 10 is installed compared to the above configuration.

[0107] Furthermore, the image forming apparatus 10 of the embodiment has a configuration in which the second connecting portion 80 is disposed at a position closer to the connection portion 11 between the first supply portion 14 and the first conveying portion 20a than the connection portion 13 between the second conveying portion 20b and the discharge portion 16. Therefore, the image forming apparatus 10 of the embodiment can suppress poor conveyance of the sheet material P between the first supply portion 14 and the first conveying portion 20a, compared to a configuration in which the second connecting portion 80 is disposed at a position closer to the connection portion 13 than the connection portion 11.

[0108] Furthermore, the image forming apparatus 10 of the embodiment has a configuration in which the second connecting portion 80 is disposed on the lower side of the housings 10b and 10c. Therefore, the image forming apparatus 10 of the embodiment can suppress poor conveyance of the sheet material P between the first supply unit 14 and the first conveying unit 20a, compared to a configuration in which the second connecting portion 80 is disposed only on the upper side of the housings 10b and 10c.

[0109] Furthermore, the image forming apparatus 10 of the embodiment has a configuration in which the position of the second connecting portion 80 in the vertical direction of the apparatus overlaps with the connection portion 11 between the first supply portion 14 and the first conveying portion 20a. Therefore, the image forming apparatus 10 of the embodiment can suppress poor conveyance of the sheet material P between the first supply portion 14 and the first conveying portion 20a, compared to a configuration in which the position of the second connecting portion 80 in the vertical direction of the apparatus is shifted from the connection portion 11 between the first supply portion 14 and the first conveying portion 20a.

[0110] Furthermore, the image forming apparatus 10 of the embodiment has a configuration in which the connection portion 11 between the first supply portion 14 and the first conveying portion 20a is disposed between the recessed portion 82b and the bolt 84 in the vertical direction of the apparatus. Therefore, the image forming apparatus 10 of the embodiment can suppress poor conveyance of the sheet material P between the first supply portion 14 and the first conveying portion 20a, compared to a configuration in which the connection portion 11 is shifted from between the recessed portion 82b and the bolt 84 in the vertical direction of the apparatus.

[0111] Furthermore, the image forming apparatus 10 of the embodiment has a configuration in which the block pair 81 and the block pair 86 are provided on both side walls of the housing 10b and the housing 10c in the device depth direction, respectively. Therefore, the image forming apparatus 10 of the embodiment can suppress poor transport of the sheet material P between the first supply unit 14 and the first conveying unit 20a, compared to a configuration in which the housings 10b and 10c are connected by a connecting portion provided on only one side wall in the device depth direction. Furthermore, the image forming apparatus 10 of the embodiment can suppress poor transport of the sheet material P between the second conveying unit 20b and the discharge unit 16, compared to a configuration in which the housings 10b and 10c are connected by a connecting portion provided on only one side wall in the device depth direction.

[0112] Furthermore, the image forming apparatus 10 of the embodiment has a configuration in which the upper part of the recessed portion 82b of the block 82 is open. Therefore, in the image forming apparatus 10 of the embodiment, the state of the positioning pin 83b inserted into the recessed portion 82b can be easily visually confirmed from above, compared to a configuration in which the upper part of the recessed portion 82b is closed.

[0113] Furthermore, the image forming apparatus 10 of the embodiment has a configuration in which the recess 82b and the positioning pin 83b are provided only in the block pair 81 of the second connecting portion 80. The image forming apparatus 10 of the embodiment will be compared with an image forming apparatus 210 of a second comparative embodiment described below.

[0114] The image forming apparatus 210 has a configuration in which the recessed portion 82b and the positioning pin 83b are provided in both the block pair 81 and the block pair 86. Except for the above points, the image forming apparatus 210 of the second comparative embodiment has the same configuration as the image forming apparatus 10 of the embodiment.

[0115] In the image forming apparatus 210 of the second comparative embodiment, when the housings 10b and 10c are positioned and connected, the positioning pins 83b of the block pair 81 and the block pair 86 must both be inserted into the recesses 82b.

[0116] On the other hand, the image forming apparatus 10 of the embodiment has a configuration in which the recess 82b and the positioning pin 83b are provided only in the block pair 81 of the second connecting portion 80. That is, in the image forming apparatus 10 of the embodiment, when positioning and connecting the housings 10b and 10c, it is sufficient to insert the positioning pin 83b of only the block pair 81 into the recess 82b, out of the block pair 81 and the block pair 86. Therefore, the image forming apparatus 10 of the embodiment improves the workability of connecting the housings 10b and 10c compared to a configuration in which the recess 82b and the positioning pin 83b are provided in both the block pair 81 and the block pair 86.

[0117] Furthermore, in the image forming apparatus 10 of the embodiment, the position adjustment unit 90 is housed in the housing 10c. Therefore, in the image forming apparatus 10 of the embodiment, the distance between the position adjustment unit 90 and the receiving position D1 of the chain gripper 50 is shorter than in a configuration in which the position adjustment unit 90 is housed in the housing 10b. Therefore, in the image forming apparatus 10 of the embodiment, it is possible to suppress conveyance failure of the sheet material P being conveyed to the forming unit 22 compared to a configuration in which the position adjustment unit 90 is housed in the housing 10b. Furthermore, in the image forming apparatus 10 of the embodiment, compared to a configuration in which the position adjustment unit 90 is housed in the housing 10b, adjustment between different housings is not required for the conveyance accuracy of the sheet material P between the position adjustment unit 90 and the chain gripper 50. Therefore, in the image forming apparatus 10 of the embodiment, compared to a configuration in which the position adjustment unit 90 is housed in the housing 10b, adjustment of the position adjustment unit 90 that adjusts the position of the sheet material P conveyed to the receiving position D1 is easier.

[0118] Furthermore, in the image forming apparatus 10 of the embodiment, the position adjustment unit 90 is disposed in the space S. Therefore, in the image forming apparatus 10 of the embodiment, it is possible to prevent the horizontal length of the housing 10c from becoming large, compared to a configuration in which the position adjustment unit 90 housed in the housing 10c is located closer to the first supply unit 14 than the chain gripper 50 in the horizontal direction.

[0119] In the image forming apparatus 10 of the embodiment, the branching portion 17 is disposed above the storage portion 12 and below the discharge portion 16 in the housing 10b. That is, in the image forming apparatus 10 of the embodiment, the discharge portion 16 is disposed above the branching portion 17. Therefore, according to the image forming apparatus 10 of the embodiment, the operator can receive the sheet material P discharged from the discharge portion 16 while standing.

[0120] Furthermore, in the image forming apparatus 10 of the embodiment, the second supply unit 15 is disposed below the branching unit 17. Therefore, in the image forming apparatus 10 of the embodiment, in a configuration including the second supply unit 15, it is possible to prevent the length of the housing 10b from increasing in the vertical direction compared to a configuration in which the second supply unit 15 is disposed above the branching unit 17.

[0121] Furthermore, the image forming apparatus 10 of the embodiment includes the measurement unit 17a of the branching unit 17. Therefore, compared to a configuration in which the dimensions of the sheet material P are measured only by the measurement unit 96, the image forming apparatus 10 of the embodiment can suppress variations in the dimensional ratio of the image formed on the back surface of the sheet material P to the image formed on the front surface of the sheet material P during double-sided printing.

[0122] Moreover, the image forming apparatus 10 of the embodiment includes a measuring unit 96. Therefore, the image forming apparatus 10 of the embodiment improves the positional accuracy of the image formed on the sheet member P relative to the sheet member P, compared to a configuration in which the dimensions of the sheet member P are measured only by the measuring unit 17a of the branching unit 17.

[0123] As described above, specific embodiments of the present invention have been described in detail, but the present invention is not limited to the above embodiments, and various modifications, changes, and improvements are possible within the scope of the technical concept of the present invention.

[0124] For example, the image forming apparatus 10 is equipped with a chain gripper 50 as a circulating part. However, the image forming apparatus according to the present invention may be configured to have a conveyor belt in place of the chain gripper 50, in which a belt body wound around multiple rolls rotates to convey the sheet material P. The rolls of the conveyor belt are an example of a rotating body. The belt body of the conveyor belt is an example of a circulating member. The conveyor belt is an example of a circulating part.

[0125] The image forming apparatus 10 is also provided with a fixing unit 40 including a heating roll 44 and a pressure roll 42. However, the fixing unit according to the present invention may be configured to include a non-contact heating means such as infrared rays.

[0126] Furthermore, the image forming apparatus 10 is an electrophotographic image forming apparatus, but the image forming apparatus 10 according to the present invention may be, for example, an inkjet type or an offset printing type. [Explanation of symbols]

[0127] 10 Image forming device 10b Housing (an example of the second housing) 10c Housing (an example of the first housing) 11 Connection 14 First supply unit (an example of a supply unit) 15 Second supply unit (an example of another supply unit) 16 Discharge section 17 Branch 17a Measuring part 20a First conveying section 20b Second conveying section 22 Formation part 40 Fixing section 50 Chain gripper (an example of a rotating part) 51 Chain (an example of a rotating member) 52, 53, 54 Sprockets (examples of rotating bodies) 80 Second connecting part (example of connecting part) 82b Recess (an example of an inserted portion) (part of a positioning portion) 82c Through hole (part of the fixed part) 83b Protrusion (part of positioning part) 83c Screw hole (part of the fixing part) 84 Bolt (part of the fixed part) 87c Through hole (part of the fixed part) 88c Screw hole (part of the fixing part) 89 Bolt (part of the fixed part) 90 Position adjustment section 96 Measuring unit (an example of another measuring unit) S space P sheet member (an example of a recording medium)

Claims

1. a forming unit for forming an image on a recording medium; a fixing unit that fixes the image formed on the recording medium; a rotating unit that transports the recording medium from the forming unit to the fixing unit by rotating a rotating member wound around a plurality of rotating bodies between the forming unit and the fixing unit; a supply unit that supplies a recording medium toward the formation unit; a discharge unit that discharges the recording medium on which the image has been fixed by the fixing unit; a branching section that branches off from the discharge section and conveys the recording medium, one surface of which has an image fixed by the fixing section, and swaps the leading end and trailing end of the recording medium to join the supplying section; a first housing that houses the forming portion, the fixing portion, and the circulating portion; a second housing connected to the first housing and accommodating the supply section, the discharge section, and the branch section; a first transport unit housed in the first housing and configured to transport the recording medium supplied from the supply unit toward the formation unit; a second conveying unit that is housed in the first housing and that conveys the recording medium on which the image is fixed by the fixing unit from the fixing unit toward the discharge unit; a connecting portion that connects the first housing and the second housing, the connecting portion being located closer to a connecting portion between the supply portion and the first transport portion than to a connecting portion between the second transport portion and the discharge portion; An image forming apparatus comprising:

2. the supply unit and the first transport unit transport the recording medium in a direction along a horizontal direction at a connection portion between the supply unit and the first transport unit, and are disposed below the first housing and the second housing; The connecting portion is disposed on the lower side of the first housing and the second housing. The image forming apparatus according to claim 1 .

3. the connecting portion overlaps with a connection portion between the supply portion and the first transport portion in the vertical direction. The image forming apparatus according to claim 2 .

4. the first housing and the second housing are aligned in a horizontal direction, the connecting portion is configured to include a positioning portion that positions the first housing and the second housing in a cross direction that crosses a direction in which the first housing and the second housing are arranged in a horizontal direction, and a fixing portion that fixes the first housing and the second housing to each other at a position that is spaced apart from the positioning portion in a vertical direction, a connection portion between the supply portion and the first transport portion is disposed between the positioning portion and the fixing portion in the up-down direction; The image forming apparatus according to claim 3 .

5. the first housing and the second housing are aligned in a horizontal direction, the connecting portion is provided on each of the side walls on both sides in a cross direction that crosses the arrangement direction of the first housing and the second housing in a horizontal direction, The image forming apparatus according to any one of claims 1 to 4.

6. the connecting portion includes a positioning portion that positions the first housing and the second housing in the intersecting direction using a protruding portion that protrudes in the alignment direction and an inserted portion into which the protruding portion is inserted, The insertion portion is open at the top. The image forming apparatus according to claim 5 .

7. The image forming apparatus according to claim 6 , wherein the positioning portion is provided on only one of the pair of connecting portions.

8. a forming unit for forming an image on a recording medium; a fixing unit that fixes the image formed on the recording medium; a rotating unit that transports the recording medium from the forming unit to the fixing unit by rotating a rotating member wound around a plurality of rotating bodies between the forming unit and the fixing unit; a supply unit that supplies a recording medium toward the formation unit; a discharge unit that discharges the recording medium on which the image has been fixed by the fixing unit; a branching section that branches off from the discharge section and conveys the recording medium, one surface of which has an image fixed by the fixing section, and swaps the leading end and trailing end of the recording medium to join the supplying section; a first housing that houses the forming portion, the fixing portion, and the circulating portion; a second housing connected to the first housing and accommodating the supply section, the discharge section, and the branch section; a position adjustment unit that is accommodated in the first housing and adjusts the position of the recording medium being transported toward the formation unit; An image forming apparatus comprising:

9. a first transport unit that is accommodated under the first housing and transports the recording medium supplied from the supply unit in a horizontal direction toward the formation unit; the circulating unit is disposed above the first transport unit, and a space is formed between the circulating unit and the first transport unit in the up-down direction, The position adjustment unit is disposed in the space. The image forming apparatus according to claim 8 .

10. a forming unit for forming an image on a recording medium; a fixing unit that fixes the image formed on the recording medium; a rotating unit that transports the recording medium from the forming unit to the fixing unit by rotating a rotating member wound around a plurality of rotating bodies between the forming unit and the fixing unit; a supply unit that supplies a recording medium toward the formation unit; a discharge unit that discharges the recording medium on which the image has been fixed by the fixing unit; a branching section that branches off from the discharge section and conveys the recording medium, one surface of which has an image fixed by the fixing section, and swaps the leading end and trailing end of the recording medium to join the supplying section; a first housing that houses the forming portion, the fixing portion, and the circulating portion; a second housing connected to the first housing and accommodating the supply section, the discharge section, and the branch section; Equipped with the branching portion is disposed above the supplying portion, The discharge portion is disposed above the branch portion. Image forming device.

11. a forming unit for forming an image on a recording medium; a fixing unit that fixes the image formed on the recording medium; a rotating unit that transports the recording medium from the forming unit to the fixing unit by rotating a rotating member wound around a plurality of rotating bodies between the forming unit and the fixing unit; a supply unit that supplies a recording medium toward the formation unit; a discharge unit that discharges the recording medium on which the image has been fixed by the fixing unit; a branching section that branches off from the discharge section and conveys the recording medium, one surface of which has an image fixed by the fixing section, and swaps the leading end and trailing end of the recording medium to join the supplying section; a first housing that houses the forming portion, the fixing portion, and the circulating portion; a second housing connected to the first housing and accommodating the supply section, the discharge section, and the branch section; another supply unit that is housed in the second housing and disposed below the branch unit, that conveys a recording medium supplied from outside the second housing and joins with the supply unit; An image forming apparatus comprising:

12. a forming unit for forming an image on a recording medium; a fixing unit that fixes the image formed on the recording medium; a rotating unit that transports the recording medium from the forming unit to the fixing unit by rotating a rotating member wound around a plurality of rotating bodies between the forming unit and the fixing unit; a supply unit that supplies a recording medium toward the formation unit; a discharge unit that discharges the recording medium on which the image has been fixed by the fixing unit; a branching section that branches off from the discharge section and conveys the recording medium, one surface of which has an image fixed by the fixing section, and swaps the leading end and trailing end of the recording medium to join the supplying section; a first housing that houses the forming portion, the fixing portion, and the circulating portion; a second housing connected to the first housing and accommodating the supply section, the discharge section, and the branch section; a measuring unit for measuring the dimensions of the recording medium conveyed to the branching unit; An image forming apparatus comprising:

13. a forming unit for forming an image on a recording medium; a fixing unit that fixes the image formed on the recording medium; a rotating unit that transports the recording medium from the forming unit to the fixing unit by rotating a rotating member wound around a plurality of rotating bodies between the forming unit and the fixing unit; a supply unit that supplies a recording medium toward the formation unit; a discharge unit that discharges the recording medium on which the image has been fixed by the fixing unit; a branching section that branches off from the discharge section and conveys the recording medium, one surface of which has an image fixed by the fixing section, and swaps the leading end and trailing end of the recording medium to join the supplying section; a first housing that houses the forming portion, the fixing portion, and the circulating portion; a second housing connected to the first housing and accommodating the supply section, the discharge section, and the branch section; a measuring unit that is housed in the first housing and that measures dimensions of the recording medium transported from the supply unit toward the formation unit; An image forming apparatus comprising:

Images