Patent ID: 12197167

DESCRIPTION OF THE EMBODIMENTS

Hereinafter, embodiments will be described in detail with reference to the attached drawings. Note, the following embodiments are not intended to limit the scope of the claimed invention. Multiple features are described in the embodiments, but limitation is not made to an invention that requires all such features, and multiple such features may be combined as appropriate. Furthermore, in the attached drawings, the same reference numerals are given to the same or similar configurations, and redundant description thereof is omitted.

(1) Image Forming Apparatus

FIG.1shows an image forming apparatus100that uses an electrophotographic method. The height direction of the image forming apparatus100(the direction from a bottom surface toward a top surface) is called a Z direction. The horizontal direction of the image forming apparatus100is called an X direction. The depth direction of the image forming apparatus100(the direction from a front surface toward a back surface) is called a Y direction. An image forming process that uses the electrophotographic method includes an exposure process, a development process, a transfer process, and a fixing process.

The image forming apparatus100includes a first chassis130and a second chassis140. The first chassis130and the second chassis140are not connected at the time of factory shipment, and become connected when installed at a customer side. The second chassis140includes positioning shafts20. The positioning shafts20fit into positioning holes19of the first chassis130.

The first chassis130includes a first frame131. A lower surface of the first frame131is provided with a plurality of casters21. An original reading apparatus190and an operation unit180are provided in an upper part of the first chassis130. The original reading apparatus190reads an original and generates image signals. The operation unit180includes an input apparatus and a display apparatus.

The first chassis130is substantially box-shaped. The first chassis130includes four side surfaces, namely a right side surface50R, a left side surface50L, a front surface50F, and a back surface50B. An exposure mechanism170a, an image forming mechanism170b, a transfer mechanism170c, storage compartments113, a conveyance mechanism170d, and the like are provided inside the first chassis130. A plurality of sheets110are housed in the storage compartments113. The conveyance mechanism170dincludes a plurality of conveyance rollers that convey sheets110fed from the storage compartments113along a conveyance path. The exposure mechanism170aexecutes the exposure process. The image forming mechanism170bexecutes the development process. The transfer mechanism170ctransfers toner images to sheets110.

The exposure mechanism170aand the image forming mechanism170bare each divided into four image forming stations120a,120b,120c, and120d. The image forming stations120a,120b,120c, and120drespectively form toner images in Y (yellow), M (magenta), C (cyan), and K (black). The image forming stations120a,120b,120c, and120dhave the same structure. Therefore, in the following description of the image forming stations120a,120b,120c, and120d, the letters a, b, c, and d appended at the end of reference signs may be omitted.

The second chassis140includes a second frame141. A lower surface of the second frame141is provided with a plurality of casters21. The second chassis140includes a fixing mechanism170ethat executes the fixing process. The second chassis140includes four side surfaces, namely a right side surface60R, a left side surface60L, a front surface60F, and a back surface60B.

(1-1) Exposure Process

The exposure mechanism170aincludes laser scanners107. The laser scanners107include a semiconductor laser108, a reflective mirror109, and a non-illustrated rotational polygonal mirror. Primary chargers111cause the surfaces of photosensitive drums105to be uniformly charged. The semiconductor lasers108output laser beams corresponding to image signals. The laser beams are deflected by the rotational polygonal mirrors. Furthermore, the photosensitive drums105are exposed to the laser beams via the reflective mirrors109. As a result, electrostatic latent images are formed on the photosensitive drums105.

(1-2) Development Process

Developers112form toner images by developing the electrostatic latent images using toner.

(1-3) Transfer Process

Primary transfer members104transfer the toner images on the photosensitive drums105to an intermediate transfer member106. The Y image, M image, C image, and K image are transferred to the intermediate transfer member106in an overlapping manner. As a result, a full-color image is formed. The intermediate transfer member106rotates, thereby conveying the toner image to a secondary transfer unit. In the secondary transfer unit, a secondary transfer roller114transfers the toner image on the intermediate transfer member106to a sheet110.

A conveyance belt118conveys the sheet110from the first chassis130to the second chassis140. The conveyance belt118is hung over a downstream roller119in a stretched state.

(1-4) Fixing Process

The fixing mechanism170eincludes a fixing device142for fixing the toner image transferred to the sheet110using heat and pressure. The fixing device142includes a fixing roller142athat applies heat to the sheet110, and a pressurizing belt142bthat causes the sheet110to come into contact with the fixing roller142aunder pressure. A heater is provided inside the fixing roller142a. As a result of rotation of both of the fixing roller142aand the pressurizing belt142b, the toner image is fixed to the sheet110, and in addition, the sheet110is conveyed from an upstream side to a downstream side.

A conveyance path144is provided downstream relative to the fixing device142. In a case where an image is formed only on one surface of the sheet110, the sheet110is conveyed to a discharge path150via the conveyance path144and loaded on a tray160. In a case where an image is formed on a back surface side of the sheet110, the sheet110is guided from the conveyance path144to a conveyance path146via a flapper145. Furthermore, the sheet110is conveyed from the conveyance path146to an inversion path148. When a sheet sensor147has detected a trailing edge of the sheet110, the inversion path148executes a switch back operation. As a result, the conveyance direction of the sheet110is inverted, and the sheet110is conveyed to a conveyance path149. The conveyance path149conveys the sheet110to the secondary transfer roller114again. The secondary transfer roller114transfers a toner image from the intermediate transfer member106to a back surface of the sheet110. The sheet110passes through the fixing device142, the conveyance path144, and the discharge path150, and then loaded on the tray160.

(2) First Embodiment

(2-1) Passing of Sheet Between Two Neighboring Chassis

As shown inFIG.1, the conveyance belt118is provided downstream relative to the transfer mechanism170c. The conveyance belt118passes a sheet110, on which an unfixed toner image is carried, from the first chassis130to a directing guide G of the second chassis140. Apart of the conveyance belt118projects from the first chassis130toward the second chassis140. The purpose thereof is to pass the sheet110in a stable manner.

The pressurizing belt142band the fixing roller142aform a fixing nip N. The directing guide G directs the sheet110passed from the conveyance belt118to the fixing nip N.

The directing guide G is provided between the downstream roller119of the conveyance belt118and the fixing nip N. The directing guide G and the downstream roller119are located so that a sheet conveyance surface of the conveyance belt118is higher than a starting position g of a directing surface of the directing guide G. The directing guide G has a guide function that directs a leading edge of the sheet110to the fixing nip N in a stable manner. Placing the leading edge of the sheet110too high relative to the directing guide G is an inappropriate case, which prevents the sheet110from being directed and guided to the fixing nip N. As a result, the sheet110gets wrinkled, or the sheet110gets stained by spattering of the unfixed toner image. If the height of the leading edge of the sheet110is too low relative to the directing guide G, the leading edge of the sheet110comes into contact with the directing guide G, thereby causing a jam.

Therefore, an error between the position of the conveyance belt118and a position that has been assumed design-wise in the height direction needs to be in a range of, for example, approximately ±0.7 mm. An error between the position of the directing guide G and a position that has been assumed design-wise in the height direction, too, needs to be in a range of, for example, approximately ±0.7 mm. Therefore, the accuracy of the height-direction position of connection between the second chassis140including the directing guide G that directs the sheet110to the fixing nip N and the first chassis130including the conveyance belt118needs to be high.

(2-2) Positioning of and Connection Between Two Chassis

FIG.2Ais a perspective view of the first frame131.FIG.2Bis a left side view of the first frame131.FIG.3Ais a perspective view of the second frame141.FIG.3Bis a right side view of the second frame141.

Fastening devices201are provided on a bottom surface of the first chassis130. The fastening devices201are fastened to a floor surface of a room by projecting the fastening devices201toward the floor surface. As a result, the first chassis130is fastened to the floor surface.

Next, an installation operator situates the second chassis140so that the right side surface60R of the second chassis140and the left side surface50L of the first chassis130face each other, and moves the second chassis140toward the first chassis130. As a result, the second chassis140is connected to the first chassis130.

As shown inFIG.2AandFIG.2B, the first frame131includes a left front support rod131aand a left back support rod131b. A passage opening132through which a sheet110passes is provided between the left front support rod131aand the left back support rod131b. The left front support rod131aincludes a positioning hole19a. The left back support rod131bincludes a positioning hole19b. Each of the positioning holes19aand19bis an oval hole that has a long diameter along the height direction.

As shown inFIG.3AandFIG.3B, the second frame141includes a right front support rod141aand a right back support rod141b. A passage opening143through which a sheet110passes is provided between the right front support rod141aand the right back support rod141b. The right front support rod141aincludes a positioning shaft20a. The right back support rod141bincludes a positioning shaft20b. The positioning shafts20aand20bproject in the direction of a normal to the right side surface60R (the X direction). The positioning shaft20afits into the positioning hole19a. The positioning shaft20bfits into the positioning hole19b. As a result, the second chassis140is positioned relative to the first chassis130. Especially, the second chassis140is positioned relative to the first chassis130in the height direction.

Regarding the depth direction (the Y direction), it is sufficient that one of the positioning shafts20aand20bbe positioned accurately. One of the positioning hole19aand the positioning hole19bof the first frame131may be enlarged in the Y direction. For example, the dimension of the positioning hole19ain the Y direction may be larger than the dimension of the positioning hole19bin the Y direction.

A description is now given of the reason why the positioning holes19aand19bare oval holes. As can be imagined fromFIG.1, the first chassis130is heavier than the second chassis140. For example, the total weight of the first chassis130is 700 kg, and the total weight of the second chassis140is 200 kg. In this case, the floor surface on which the first chassis130has been installed sinks down in the −Z direction compared to the floor surface on which the second chassis140has been installed. As a result, the positions of the positioning holes19aand19bcan be lower than the positions of the positioning shafts20aand20b. In view of this, the positioning holes19aand19bhave a shape of an oval hole. In this way, the first chassis130and the second chassis140can be joined to each other without the positioning shafts20aand20binterfering with the left front support rod131aand the left back support rod131bof the first chassis130.

The height of the second chassis140relative to the first chassis130is adjusted using the casters21in order to appropriately pass a sheet110from the first chassis130to the second chassis140.

FIG.4Ais a perspective view of a caster21.FIG.4Bis a cross-sectional view of the caster21. The caster21includes a main body21bmade of steel. A wheel21ais swivelably attached to the main body21bvia a wheel shaft21h. A threaded portion21fis formed in the main body21b. The threaded portion21fis joined to a threaded portion21gprovided in a mount21c. Meanwhile, the mount21cis fastened to a bottom surface frame311of the second chassis140via four screws21d. In order to prevent separation of the threaded portion21ffrom the mount21c, the threaded portion21fis joined to the mount21cvia a nut21e.

In a case where the height of the caster21is to be adjusted, the nut21eis loosened first. Next, the main body21bis rotated in the CW direction. As a result, the threaded portion21fmoves relative to the threaded portion21g, and the wheel21aapproaches the mount21c. That is to say, the second chassis140becomes relatively low compared to the first chassis130.

Rotating the main body21bin the CCW direction makes the second chassis140relatively high compared to the first chassis130. In a case where the first chassis130has sunk down compared to the second chassis140, the main body21bis rotated in the CCW direction to align the first chassis130and the second chassis140in the height direction.

FIG.5Ais a front view showing a state of connection between the first frame131and the second frame141.FIG.5Bis a back view showing a state of connection between the first frame131and the second frame141. The first chassis130and the second chassis140are connected to each other by two connectors Pa and Pb. Specifically, the connector Pa connects together the left front support rod131aand the right front support rod141a. The connector Pb connects together the left back support rod131band the right back support rod141b.

(2-3) Influence of Floor Surface when Connecting Two Chassis to Each Other

Once the second chassis140has been joined to the first chassis130and the height adjustment using the casters21has been completed, the first chassis130and the second chassis140are connected to each other via the two connectors Pa and Pb.

Incidentally, the height adjustment that uses the casters21alone may cause the horizontal angle formed by the second chassis140together with the first chassis130to deviate from a horizontal angle that has been assumed design-wise. Therefore, the connectors Pa and Pb need to include a fine adjustment mechanism.

FIG.6AandFIG.6Bare diagrams for describing the connectors Pa and Pb according to a comparative example. Especially, the connector Pb is realized by two hinges. As shown inFIG.6A, it is assumed that the floor surface located beneath the second chassis140is inclined as indicated by a dash line. In this case, the second chassis140also becomes inclined along the floor. Although adjusting the casters21alleviates the inclination of the second chassis140to some extent, it is difficult to achieve an exactly level placement of the second chassis140.

Furthermore, in a case where the second chassis140is inclined relative to the first chassis130, a load F is applied to the connector Pb. This may consequently damage the connector Pb. In addition, as shown inFIG.6B, if an operator attempts to pivot the second frame141around the connector Pb in the CW direction or the CCW direction, the pivot resistance of the second chassis140increases due to the load F applied to the connector Pb. This makes it difficult for the operator to make the angle adjustment.

FIG.7AandFIG.7Bare diagrams for describing the connection between the first chassis130and the second chassis140via two connectors P (connectors Pa and Pb) that have been improved. As shown inFIG.7B, although the two connectors Pa and Pb are components having the same shape, they are joined to the first chassis130and the second chassis140in such a manner that their vertical orientations are reverse of each other. By using the same components as the two connectors Pa and Pb, the manufacturing cost of the two connectors Pa and Pb is reduced. Note that as a plurality of components that constitute the two connectors Pa and Pb are the same components, they are given the same reference signs.

Each of the connectors Pa and Pb includes a first connector component P1aand a second connector component P2a. The second connector component P2aincludes a shaft portion P2d. The shaft portion P2dprojects in the Y direction, and fits into the first connector component P1aand the second frame141. Note that on the front surface side, a gap da is ensured between the first connector component P1aand the second chassis140. On the back surface side, a gap db is ensured between the first connector component P1aand the second chassis140.

In a case where the floor is inclined as shown inFIG.7A, the second chassis140pivots around the shaft portions P2d. Therefore, a load is not easily applied to the connectors Pa and Pb. Therefore, the improved connectors Pa and Pb according to the first embodiment are not easily damaged.

In a case where the floor surface is not level, the second chassis140tends to pivot around the Y axis. In view of this, the connectors Pa and Pb are provided in the vicinity of the conveyance belt118, the fixing device142, and the directing guide G. That is to say, a pivot axis around the Y axis exists in the vicinity of the passage openings132and142for sheets110. Therefore, the displacements in the vicinity of the conveyance belt118, the fixing device142, and the directing guide G are reduced, thereby allowing sheets110to be passed with high accuracy.

Incidentally, as shown inFIG.6AandFIG.6B, the pivot center of Z-axis rotation of the second chassis140according to the comparative example is in the hinge (connector Pb). Therefore, in the comparative example, if the angle of the second chassis140is changed, a gap d1between the first chassis130and the second chassis140also increases accordingly.

On the other hand, as shown inFIG.7AandFIG.7B, according to the first embodiment, the angle adjustment is executed with the connectors Pa and Pb on both of the front surface side and the back surface side of the second chassis140. Therefore, a gap d2between the first chassis130and the second chassis140becomes smaller than the gap d1according to the comparative example. In this way, when the gap in the X direction is small, the integrity of the external design is maintained even if the angle adjustment has been made to the first chassis130and the second chassis140around the Z axis.

(2-4) Connection Method

FIG.8Ashows the details of the connector Pa.FIG.8Bshows the details of the connector Pb. As shown inFIG.8A, the connector Pa connects together the front surface50F of the first chassis130and the front surface60F of the second chassis140. As shown inFIG.8B, the connector Pb connects together the back surface50B of the first chassis130and the back surface60B of the second chassis140.

First, the first connector component P1aof the connector Pa is fastened to the left front support rod131aof the first frame131via a fastener P1e(e.g., a screw or a threaded member). Similarly, the first connector component P1aof the connector Pb is fastened to the left back support rod131bof the first frame131via a fastener P1e(e.g., a screw or a threaded member).

The second connector component P2ais fastened to the first connector component P1avia a fastener P2e(e.g., a screw or a threaded member). The connector component P2aincludes a shaft portion P2dthat has been formed integrally with the connector component P2a. The shaft portion P2dof the connector Pa is fitted into a connection hole Ha provided in the right front support rod141aof the second frame141. The shaft portion P2dof the connector Pb is fitted into a connection hole Hb provided in the right back support rod141bof the second frame141. As a result, the second frame141is positioned relative to the first frame131in the X direction. The connection holes Ha and Hb are oval holes that have a long diameter along the height direction, for the same reason as the positioning holes19aand19b.

(2-5) Detailed Structure of Connectors

FIG.9AtoFIG.9Dshow a structure of the connectors Pa and Pb according to the first embodiment. The second connector component P2aincludes an indicator P2cwith a triangle shape. On the other hand, the first connector component P1aincludes markings Plc corresponding to the indicator P2c. The markings Plc include groove-like vertical lines P1fthat have been formed at an equal interval. The indicator P2cand the markings Plc can be indexes in adjusting the horizontal angle between the first chassis130and the second chassis140.

The second connector component P2aincludes a long hole portion P2b. The first connector component P1aincludes an embossed portion P1bthat is intended to be inserted or fit into the long hole portion P2b. The embossed portion P1bis a shaft-like projection. Relative movement of the embossed portion P1bin the long hole portion P2benables relative movement of the first connector component P1aand the second connector component P2ain the X direction. That is to say, the long hole portion P2bhas a long diameter along the X direction.

The shaft portion P2dhas been joined to and integrated with the second connector component P2a. The shaft portion P2dis movable along a guiding groove P1dprovided in the first connector component P1a. The guiding groove P1dand the long hole portion P2bare provided substantially parallel to each other. Therefore, when the embossed portion P1bmoves along the long hole portion P2b, the shaft portion P2dmoves along the guiding groove P1d. In this way, the first connector component P1aand the second connector component P2acan move in the X direction without rotating.

As shown inFIG.9D, the indicator P2cprovided on one end of the second connector component P2aindicates the markings Plc provided on the first connector component P1a. The markings Plc include, for example, a plurality of vertical lines P1fthat have been formed at an interval of 1 mm by stamping and the like.

As stated earlier, the first connector component P1aand the second connector component P2acan relatively move in the X direction while the embossed portion P1bis restrained by the long hole portion P2band the shaft portion P2dis restrained by the guiding groove P1d. The amount of this movement can be adjusted by pointing the indicator P2cto one of the vertical lines P1f. Once the adjustment has been completed, the first connector component P1aand the second connector component P2aare fixed to each other via the fastener P2e. When the plurality of vertical lines P1fhave been formed at an interval of 1 mm, the relative positions of the first connector component P1aand the second connector component P2acan also be adjusted at an interval of 1 mm. Note that 1 mm is merely an example, and the interval among the plurality of vertical lines P1fmay be smaller than 1 mm, or may exceed 1 mm.

As shown inFIG.9D, among the plurality of lines P1f, the two lines P1fat the center may be longer in length than the six lines P1farranged at the ends. The two lines P1fat the center indicate an initial position between the first chassis130and the second chassis140that has been assumed design-wise (a position before the angle adjustment).

(2-6) Position Adjustment Between Two Chassis

The following describes a procedure of the angle adjustment between the first chassis130and the second chassis140around the Z axis. As stated earlier, two neighboring chassis (the first chassis130and the second chassis140) are connected in a state where the two chassis have been aligned in orientation. However, there are cases where an appropriate angular relationship is not established between a sheet processing unit provided inside one chassis and a sheet processing unit provided inside another chassis. For example, in a case where processing is executed continuously with respect to a plurality of sheets110, the angle formed by the secondary transfer roller114and the fixing device142needs to be maintained at an appropriate angle. Similarly, the angle formed by the conveyance belt118and the fixing device142, too, needs to be maintained at an appropriate angle. There are cases where these two sheet processing units are required to be parallel to each other, as well as cases where they are required to form a predetermined angle. However, a certain angular relationship that has been assumed design-wise may not be established even if the two chassis have been simply oriented to be parallel to each other. In contrast, it is also possible to mount a mechanism that adjusts the angle of the sheet processing unit inside one chassis, and a mechanism that adjusts the angle of the sheet processing unit inside another chassis. However, restrictions on the sizes of the two chassis may cause difficult in mounting these mechanisms on the two chassis. Even if the adjustment mechanisms have been respectively mounted on the two chassis, the adjustment thereof is expected to be extremely complicated for an operator.

In a case where the angle formed by the two sheet processing units is not appropriate, the following problem can arise. For example, assume that the angle formed by the fixing device142and the conveyance belt118is not appropriate. In this case, when a sheet110enters the fixing nip N, the sheet110gets twisted. As a result, the sheet110gets wrinkled, or a toner image on the sheet110gets uneven. Alternatively, the degree of alignment of a plurality of sheets110discharged from the discharge path150to the tray160, or the degree of alignment of the sheets110relative to the tray160, can decrease.

FIG.10shows an adjustment procedure executed by an operator. In step S1001, the operator forms an image on a sheet110by controlling the image forming apparatus100via the operation unit180.

In step S1002, the operator measures the degree of alignment, wrinkles, and image unevenness of the sheet110output from the image forming apparatus100to the tray160. For example, the operator may instruct the image forming apparatus100to stop the conveyance of the sheet110via the operation unit180at a timing when a leading edge of the sheet110has been discharged from the discharge path150to the outside of the image forming apparatus100. The operator measures the amount of displacement of the sheet110in the Y direction.

In step S1003, the operator determines whether the measurement result is favorable. If the measurement result is favorable, the operator terminates the adjustment operation. On the other hand, if the measurement result is not favorable, the operator proceeds to processing of step S1004. The case where the measurement result is not favorable is, for example, a case where the amount of displacement of the sheet110in the Y direction has deviated from a pass range.

In step S1004, the operator adjusts the two connectors Pa and Pb. Thereafter, the operator returns to step S1001from step S1004, and forms an image on the next sheet110. Then, steps S1002to S1004are repeated. Steps S1001to S1004are repeated until the amount of displacement falls in the pass range.

FIG.11AtoFIG.11Dshow a method of adjusting the connectors Pa and Pb when causing the second chassis140to pivot around the Z axis relative to the first chassis130. AlthoughFIG.11AandFIG.11Conly show the connector Pa, the method of adjusting the connector Pb is the same as the method of adjusting the connector Pa as the connector Pb has the same shape as the connector Pa.FIG.11Eshows the angle adjustment of the first chassis130and the second chassis140as viewed from the top surface side.

The first chassis130is heavier than the second chassis140. Therefore, once the first chassis130has been fixed to the floor, it is difficult to readjust the first chassis130. For this reason, an operator changes the angle of the second chassis140around the Z axis relative to the first chassis130.

The operator loosens the fastener P2evia which the first connector component P1aof the connector Pa is fixed to the right front support rod141aof the second chassis140. The operator loosens the fastener P2evia which the first connector component P1aof the connector Pb is fixed to the right back support rod141bof the second chassis140.

The operator moves both of the connector Pa on the front surface side and the connector Pb on the back surface side in the same direction by the same distance. For example, as shown inFIG.11AandFIG.11B, the operator moves the connector component P2ain the +X direction in increments of 1 mm relative to the connector component P1a. In this case, as shown inFIG.11E, the second chassis140pivots clockwise (in the CW direction).

As shown inFIG.11CandFIG.11D, the operator moves the connector component P2ain the −X direction in increments of 1 mm relative to the connector component P1a. In this case, as shown inFIG.11E, the second chassis140pivots counterclockwise (in the CCW direction).

As shown inFIG.11E, the two connectors Pa and Pb are both placed at an equal distance from a conveyance center line Cp of sheets110. In this case, the second chassis140can pivot with one point on the conveyance center line Cp acting as an origin.

Once the angle adjustment of the second chassis140relative to the first chassis130has been completed, the operator tightens both of the fastener P2eon the back surface side and the fastener P2eon the front surface side. As a result, the second chassis140is fixed to the first chassis130.

As shown inFIG.11E, there is a gap da between the connector Pa and the right front support rod141a, and there is a gap db between the connector Pb and the right back support rod141b. The gap da prevents interference between the connector Pa and the right front support rod141awhen the operator has caused the second chassis140to pivot relative to the first chassis130. The gap dd prevents interference between the connector Pb and the right back support rod141bwhen the operator has caused the second chassis140to pivot relative to the first chassis130.

(3) Second Embodiment

A second embodiment 2 pertains to an assistance structure that assists the second chassis140in pivoting relative to the first chassis130.FIG.12Ashows the second frame141according to the second embodiment.FIG.12Bshows a support table20cthat has been fixed to or integrated with the bottom surface frame311, and a pivot shaft20d.FIG.12Cshows the first frame131according to the second embodiment.FIG.12Dshows a recess19cprovided in a bottom surface frame1211of the first frame131. The position of the recess19c, the position of the pivot shaft20d, the size of a guiding groove of the recess19c, and the height and diameter of the pivot shaft20dhave been designed so that the pivot shaft20dfits in the recess19c.

FIG.13is a plan view showing a state where the angle adjustment is executed while the first chassis130and the second chassis140are connected to each other.

As shown inFIG.12AandFIG.12B, the support table20cthat projects toward the first frame131is provided in a lower part of the second frame141. The support table20cis, for example, fixed to the bottom surface frame311of the second frame141via a fastener (e.g., a screw) and the like. The pivot shaft20dthat extends parallel to the Z direction is provided on the support table20c.

As shown inFIG.13, the position of the pivot shaft20din the Y direction coincides with the conveyance center line Cp. For example, the distance from the back surface60B of the second chassis140to the pivot shaft20dis substantially equal to the distance from the front surface60F of the second chassis140to the pivot shaft20d. Alternatively, the distance from the right back support rod141bto the pivot shaft20dis substantially equal to the distance from the right front support rod141ato the pivot shaft20d.

Incidentally, as shown inFIG.12CandFIG.12D, the recess19cthat determines the position of the pivot shaft20dis formed in a lower part of the first frame131. As shown inFIG.13, the central position of the recess19cin the Y direction also coincides with the conveyance center line Cp.

In the process of positioning of the second chassis140in the X direction relative to the first chassis130, the pivot shaft20dis positioned by being directed and guided to the recess19c. The method of adjusting the angle between the first chassis130and the second chassis140around the Z axis according to the second embodiment is the same as the method according to the first embodiment. However, when an operator causes the second chassis140to pivot in the CW direction or the CCW direction, the pivot shaft20dis pivotably held by the recess19c. That is to say, the pivot shaft20dand the recess19cform an assistance structure that assists the second chassis140in pivoting relative to the first chassis130.

(4) Others

The first and second embodiments cause the second chassis140to pivot substantially around the Z axis relative to the first chassis130. Especially, as the connectors Pa and Pb are adopted, the pivot center of the second chassis140relative to the first chassis130exists in the vicinity of the center of the site of connection between the first chassis130and the second chassis140. This makes it possible to install the image forming apparatus100flexibly relative to the inclination of the floor surface. That is to say, even if the inclination of the floor surface of the first chassis130is different from the inclination of the floor surface of the second chassis140, the angle formed by the first chassis130and the second chassis140can be adjusted appropriately.

As the pivot center of the second chassis140exists in the vicinity of the center of the site of connection between the first chassis130and the second chassis140, the amount of fluctuation in a gap between the first chassis130and the second chassis140, which is caused by the angle adjustment around the Z axis, is reduced compared to a conventional case.

The connectors Pa and Pb are provided with the indicator and markings that are helpful in adjusting the pivot angle around the Z axis. In this way, the pivot angle can be adjusted accurately.

In the first and second embodiments, the first chassis130includes a processing unit that executes the exposure process, the development process, and the transfer process, and the second chassis140includes a processing unit that executes the fixing process; however, this is merely an example. For example, the first chassis130may include a processing unit that executes the exposure process, the development process, the transfer process, and the fixing process, and the second chassis140may include a processing unit that executes postprocessing with respect to sheets, or a processing unit that sorts and discharges the sheets. Alternatively, the first chassis130may include a processing unit that feeds sheets, and the second chassis140may include processing that executes the exposure process, the development process, the transfer process, and the fixing process. As described above, a plurality of processing units that are involved in image formation may be distributed to a plurality of chassis using any method.

Although the electrophotographic method is adopted as the image forming method, this is also a mere example. The image forming method may be, for example, another image forming method, such as an inkjet recording method and a dye-sublimation method.

(5) Technical Ideas Derived from Embodiments

[Item 1]

The left side surface50L of the first chassis130is an example of a first side surface. The front surface50F is an example of a second side surface. The back surface50B is an example of a third side surface. The right side surface50R is an example of a fourth side surface. The right side surface60R of the second chassis140is an example of a fifth side surface. The front surface60F is an example of a sixth side surface. The back surface60B is an example of a seventh side surface. The left side surface60L is an example of an eighth side surface. The connector component P1aof the connector Pa is an example of a first connector. The connector component P2aof the connector Pa is an example of a second connector. The connector component P1aof the connector Pb is an example of a third connector. The connector component P2aof the connector Pb is an example of a fourth connector. The markings Plc of the connector Pa represent an example of a first mark (scale). The indicator P2cof the connector Pa represents an example of a first indicator. As described above, according to the invention of Item 1, a pivot axis of the second chassis relative to the first chassis is located substantially in the vicinity of the center of connected surfaces (opposing surfaces) of the first chassis and the second chassis. This allows the second chassis to pivot smoothly relative to the first chassis. Furthermore, a gap between the first chassis and the second chassis can be made small compared to conventional cases. In addition, as the indicator and the mark (scale) are provided, an operator can accurately understand a pivot amount. Therefore, the angle adjustment between the two chassis is facilitated.[Item 2]

The markings Plc of the connector Pb represent an example of a second mark (scale). The indicator P2cof the connector Pb represents an example of a second indicator. As described above, the mark and the indicator are provided on the third connector and the fourth connector as well; this further facilitates the angle adjustment between the two chassis.[Item 3]

As shown inFIG.8A, the oval hole Ha is an example of a fitting hole. In this way, the second connector is expected to be easily installed on the second chassis, even if the height of the second chassis is different from an assumed height due to the inclination of a floor surface.[Item 4]

As shown inFIG.8B, the oval hole Hb is an example of a fitting hole. In this way, the fourth connector is expected to be easily installed on the second chassis, even if the height of the second chassis is different from an assumed height due to the inclination of the floor surface.[Item 5]

As shown inFIG.7B, the conveyance center line Cp may exist at a position that is substantially at an equal distance from the first connector component P1aof the connector Pa and from the first connector component P1aof the connector Pb. In this way, when looking down the image forming apparatus100from above, the pivot center of the second chassis relative to the first chassis is located substantially at the center of the vicinity of the site of connection. This allows the second chassis to pivot easily. Furthermore, the distance d2between the opposing connected portions can be reduced. As a result, the integrity of the external design of the image forming apparatus100is maintained.[Item 6]

As shown inFIG.7B, the conveyance center line Cp may exist at a position that is substantially at an equal distance from the second connector component P2aof the connector Pa and from the second connector component P2aof the connector Pb. This allows the second chassis to pivot more easily. Furthermore, the distance d2between the opposing connected portions can be reduced.[Item 7]

As shown inFIG.9A,FIG.9B, andFIG.11B, the second connector component P2amay include a guiding hole p2jthrough which the fastener P2eis inserted and which is parallel to the guiding groove P1d. This is expected to allow the second chassis140to move easily in the first direction.[Item 8]

As shown inFIG.9Cand the like, the embossed portion P1bis an example of a fitting boss. The long hole portion P2bis an example of a guiding hole. This is expected to allow the second chassis140to move easily in the first direction.[Item 9]

As shown inFIG.9A,FIG.9B, andFIG.11B, the connector Pb may also include the above-described fastener and guiding hole.[Item 10]

As shown inFIG.11Cand the like, the connector Pb may also include the above-described fastener and guiding hole.[Item 11]

As a plurality of lines are provided as shown inFIG.11D, the operator is expected to visually understand an amount of adjustment in the first direction with ease.[Item 12]

As the plurality of lines vary in length as shown inFIG.11D, the operator is expected to visually understand an amount of adjustment in the first direction with ease.[Item 13]

As a plurality of lines are provided also on the connector Pb as shown inFIG.11D, the operator is expected to visually understand an amount of adjustment in the first direction with ease.[Item 14]

As the plurality of lines provided on the connector Pb vary in length as shown inFIG.11D, the operator is expected to visually understand an amount of adjustment in the first direction with ease.[Item 15]

As the first indicator has a triangle shape, the operator is expected to be able to immediately understand the current amount of adjustment.[Item 16]

As the second indicator has a triangle shape, the operator is expected to be able to immediately understand the current amount of adjustment.[Item 17]

As shown inFIG.12D, the recess19cis an example of a third fitting groove. As shown inFIG.12B, the pivot shaft20dis an example of a fitting boss.

This is expected to allow easy connection between the first chassis130and the second chassis140.[Item 18]

As shown inFIG.12B, the support table20cis an example of a support portion. This is expected to allow easy connection between the first chassis130and the second chassis140.[Item 19]

The distance from the fitting boss to the sixth side surface may be equal to the distance from the fitting boss to the seventh side surface. This is expected to cause the fitting boss, too, to coincide with the pivot center, and allow the second chassis to pivot more easily.[Item 20]

The first chassis may house an image forming unit. The second chassis may house a fixing unit.[Item 21]

As shown inFIG.1, the conveyance belt118is an example of a conveyance roller. This is expected to allow a sheet that carries an unfixed toner image thereon to be passed from the first chassis to the second chassis in a stable manner.[Item 22]

A conveyance guide G is an example of a guiding member. Adopting such an arrangement is expected to allow the sheet to be passed from the first chassis to the second chassis in a more stable manner.[Item 23]

Adjusting the height of the second chassis is expected to reduce the influence of the inclination of the floor surface.

Other Embodiments

Embodiment(s) of the present invention can also be realized by a computer of a system or apparatus that reads out and executes computer executable instructions (e.g., one or more programs) recorded on a storage medium (which may also be referred to more fully as a ‘non-transitory computer-readable storage medium’) to perform the functions of one or more of the above-described embodiment(s) and/or that includes one or more circuits (e.g., application specific integrated circuit (ASIC)) for performing the functions of one or more of the above-described embodiment(s), and by a method performed by the computer of the system or apparatus by, for example, reading out and executing the computer executable instructions from the storage medium to perform the functions of one or more of the above-described embodiment(s) and/or controlling the one or more circuits to perform the functions of one or more of the above-described embodiment(s). The computer may comprise one or more processors (e.g., central processing unit (CPU), micro processing unit (MPU)) and may include a network of separate computers or separate processors to read out and execute the computer executable instructions. The computer executable instructions may be provided to the computer, for example, from a network or the storage medium. The storage medium may include, for example, one or more of a hard disk, a random-access memory (RAM), a read only memory (ROM), a storage of distributed computing systems, an optical disk (such as a compact disc (CD), digital versatile disc (DVD), or Blu-ray Disc (BD)™), a flash memory device, a memory card, and the like.

While the present invention has been described with reference to exemplary embodiments, it is to be understood that the invention is not limited to the disclosed exemplary embodiments. The scope of the following claims is to be accorded the broadest interpretation so as to encompass all such modifications and equivalent structures and functions.

This application claims the benefit of Japanese Patent Application No. 2022-167902, filed Oct. 19, 2022 which is hereby incorporated by reference herein in its entirety.